Merge branch 'socks_trunnel4_squashed_merged'

changes/ticket3569_part1

@@ -0,0 +1,6 @@
+  o Code simplification and refactoring:
+    - Rework Tor SOCKS server code to use Trunnel and benefit from
+      autogenerated functions for parsing and generating SOCKS wire
+      format. New implementation is cleaner, more maintainable and
+      should be less prone to heartbleed-style vulnerabilities.
+      Implements a significant fraction of ticket 3569.

scripts/codegen/fuzzing_include_am.py

@@ -12,6 +12,7 @@ FUZZERS = """
 	http-connect
 	iptsv2
 	microdesc
+	socks
 	vrs
 """
 

src/core/or/socks_request_st.h

@@ -70,6 +70,8 @@ struct socks_request_t {
   /** The negotiated password value if any (for socks5). This value is NOT
    * nul-terminated; see passwordlen for its length. */
   char *password;
+
+  uint8_t socks5_atyp; /* SOCKS5 address type */
 };
 
 #endif

src/test/fuzz/fuzz_socks.c

@@ -0,0 +1,50 @@
+/* Copyright (c) 2016-2018, The Tor Project, Inc. */
+/* See LICENSE for licensing information */
+
+#include "orconfig.h"
+
+#define BUFFERS_PRIVATE
+#include "core/or/or.h"
+
+#include "lib/container/buffers.h"
+#include "lib/err/backtrace.h"
+#include "lib/log/log.h"
+#include "core/proto/proto_socks.h"
+#include "feature/client/addressmap.h"
+
+#include "test/fuzz/fuzzing.h"
+
+int
+fuzz_init(void)
+{
+  addressmap_init();
+  return 0;
+}
+
+int
+fuzz_cleanup(void)
+{
+  addressmap_free_all();
+  return 0;
+}
+
+int
+fuzz_main(const uint8_t *stdin_buf, size_t data_size)
+{
+  buf_t *buffer = buf_new_with_data((char*)stdin_buf, data_size);
+  if (!buffer) {
+    tor_assert(data_size==0);
+    buffer = buf_new();
+  }
+
+  socks_request_t *request = socks_request_new();
+
+  int r = fetch_from_buf_socks(buffer, request, 0, 0);
+  log_info(LD_GENERAL, "Socks request status: %d", r);
+
+  /* Reset. */
+  buf_free(buffer);
+  socks_request_free(request);
+
+  return 0;
+}

src/test/fuzz/include.am

@@ -17,7 +17,7 @@ FUZZING_LIBS = \
 	@TOR_ZSTD_LIBS@
 
 oss-fuzz-prereqs: \
-	$(TOR_INTERNAL_TESTING_LIBS)
+    $(TOR_INTERNAL_TESTING_LIBS)
 
 noinst_HEADERS += \
 	src/test/fuzz/fuzzing.h
@@ -120,6 +120,14 @@ src_test_fuzz_fuzz_microdesc_CFLAGS = $(FUZZING_CFLAGS)
 src_test_fuzz_fuzz_microdesc_LDFLAGS = $(FUZZING_LDFLAG)
 src_test_fuzz_fuzz_microdesc_LDADD = $(FUZZING_LIBS)
 
+src_test_fuzz_fuzz_socks_SOURCES = \
+	src/test/fuzz/fuzzing_common.c \
+	src/test/fuzz/fuzz_socks.c
+src_test_fuzz_fuzz_socks_CPPFLAGS = $(FUZZING_CPPFLAGS)
+src_test_fuzz_fuzz_socks_CFLAGS = $(FUZZING_CFLAGS)
+src_test_fuzz_fuzz_socks_LDFLAGS = $(FUZZING_LDFLAG)
+src_test_fuzz_fuzz_socks_LDADD = $(FUZZING_LIBS)
+
 src_test_fuzz_fuzz_vrs_SOURCES = \
 	src/test/fuzz/fuzzing_common.c \
 	src/test/fuzz/fuzz_vrs.c
@@ -140,6 +148,7 @@ FUZZERS = \
 	src/test/fuzz/fuzz-http-connect \
 	src/test/fuzz/fuzz-iptsv2 \
 	src/test/fuzz/fuzz-microdesc \
+	src/test/fuzz/fuzz-socks \
 	src/test/fuzz/fuzz-vrs
 
 # ===== libfuzzer
@@ -222,6 +231,13 @@ src_test_fuzz_lf_fuzz_microdesc_CFLAGS = $(LIBFUZZER_CFLAGS)
 src_test_fuzz_lf_fuzz_microdesc_LDFLAGS = $(LIBFUZZER_LDFLAG)
 src_test_fuzz_lf_fuzz_microdesc_LDADD = $(LIBFUZZER_LIBS)
 
+src_test_fuzz_lf_fuzz_socks_SOURCES = \
+	$(src_test_fuzz_fuzz_socks_SOURCES)
+src_test_fuzz_lf_fuzz_socks_CPPFLAGS = $(LIBFUZZER_CPPFLAGS)
+src_test_fuzz_lf_fuzz_socks_CFLAGS = $(LIBFUZZER_CFLAGS)
+src_test_fuzz_lf_fuzz_socks_LDFLAGS = $(LIBFUZZER_LDFLAG)
+src_test_fuzz_lf_fuzz_socks_LDADD = $(LIBFUZZER_LIBS)
+
 src_test_fuzz_lf_fuzz_vrs_SOURCES = \
 	$(src_test_fuzz_fuzz_vrs_SOURCES)
 src_test_fuzz_lf_fuzz_vrs_CPPFLAGS = $(LIBFUZZER_CPPFLAGS)
@@ -241,6 +257,7 @@ LIBFUZZER_FUZZERS = \
 	src/test/fuzz/lf-fuzz-http-connect \
 	src/test/fuzz/lf-fuzz-iptsv2 \
 	src/test/fuzz/lf-fuzz-microdesc \
+	src/test/fuzz/lf-fuzz-socks \
 	src/test/fuzz/lf-fuzz-vrs
 
 else
@@ -305,6 +322,11 @@ src_test_fuzz_liboss_fuzz_microdesc_a_SOURCES = \
 src_test_fuzz_liboss_fuzz_microdesc_a_CPPFLAGS = $(LIBOSS_FUZZ_CPPFLAGS)
 src_test_fuzz_liboss_fuzz_microdesc_a_CFLAGS = $(LIBOSS_FUZZ_CFLAGS)
 
+src_test_fuzz_liboss_fuzz_socks_a_SOURCES = \
+	$(src_test_fuzz_fuzz_socks_SOURCES)
+src_test_fuzz_liboss_fuzz_socks_a_CPPFLAGS = $(LIBOSS_FUZZ_CPPFLAGS)
+src_test_fuzz_liboss_fuzz_socks_a_CFLAGS = $(LIBOSS_FUZZ_CFLAGS)
+
 src_test_fuzz_liboss_fuzz_vrs_a_SOURCES = \
 	$(src_test_fuzz_fuzz_vrs_SOURCES)
 src_test_fuzz_liboss_fuzz_vrs_a_CPPFLAGS = $(LIBOSS_FUZZ_CPPFLAGS)
@@ -322,6 +344,7 @@ OSS_FUZZ_FUZZERS = \
 	src/test/fuzz/liboss-fuzz-http-connect.a \
 	src/test/fuzz/liboss-fuzz-iptsv2.a \
 	src/test/fuzz/liboss-fuzz-microdesc.a \
+	src/test/fuzz/liboss-fuzz-socks.a \
 	src/test/fuzz/liboss-fuzz-vrs.a
 
 else

src/test/test_socks.c

@@ -84,7 +84,7 @@ test_socks_4_supported_commands(void *ptr)
 
   tt_int_op(0,OP_EQ, buf_datalen(buf));
 
-  /* SOCKS 4 Send CONNECT [01] to IP address 2.2.2.2:4370 */
+  /* SOCKS 4 Send CONNECT [01] to IP address 2.2.2.3:4370 */
   ADD_DATA(buf, "\x04\x01\x11\x12\x02\x02\x02\x03\x00");
   tt_int_op(fetch_from_buf_socks(buf, socks, get_options()->TestSocks,
                                  get_options()->SafeSocks),
@@ -100,7 +100,7 @@ test_socks_4_supported_commands(void *ptr)
   tt_int_op(0,OP_EQ, buf_datalen(buf));
   socks_request_clear(socks);
 
-  /* SOCKS 4 Send CONNECT [01] to IP address 2.2.2.2:4369 with userid*/
+  /* SOCKS 4 Send CONNECT [01] to IP address 2.2.2.4:4369 with userid*/
   ADD_DATA(buf, "\x04\x01\x11\x12\x02\x02\x02\x04me\x00");
   tt_int_op(fetch_from_buf_socks(buf, socks, 1, 0),
             OP_EQ, 1);
@@ -166,7 +166,7 @@ test_socks_4_bad_arguments(void *ptr)
   tt_int_op(fetch_from_buf_socks(buf, socks, 1, 0),
             OP_EQ, -1);
   buf_clear(buf);
-  expect_log_msg_containing("user name too long; rejecting.");
+  expect_log_msg_containing("socks4: parsing failed - invalid request.");
   mock_clean_saved_logs();
 
   /* Try with 2000-byte hostname */
@@ -194,7 +194,7 @@ test_socks_4_bad_arguments(void *ptr)
   tt_int_op(fetch_from_buf_socks(buf, socks, 1, 0),
             OP_EQ, -1);
   buf_clear(buf);
-  expect_log_msg_containing("Destaddr too long.");
+  expect_log_msg_containing("parsing failed - invalid request.");
   mock_clean_saved_logs();
 
   /* Socks4, bogus hostname */
@@ -648,7 +648,8 @@ test_socks_5_malformed_commands(void *ptr)
   tt_int_op(5,OP_EQ,socks->socks_version);
   tt_int_op(10,OP_EQ,socks->replylen);
   tt_int_op(5,OP_EQ,socks->reply[0]);
-  tt_int_op(SOCKS5_ADDRESS_TYPE_NOT_SUPPORTED,OP_EQ,socks->reply[1]);
+  /* trunnel parsing will fail with -1 */
+  tt_int_op(SOCKS5_GENERAL_ERROR,OP_EQ,socks->reply[1]);
   tt_int_op(1,OP_EQ,socks->reply[3]);
 
  done:

src/trunnel/include.am

@@ -10,7 +10,8 @@ TRUNNELINPUTS = \
 	src/trunnel/ed25519_cert.trunnel \
 	src/trunnel/link_handshake.trunnel \
 	src/trunnel/pwbox.trunnel \
-	src/trunnel/channelpadding_negotiation.trunnel
+	src/trunnel/channelpadding_negotiation.trunnel \
+	src/trunner/socks5.trunnel
 
 TRUNNELSOURCES = \
 	src/ext/trunnel/trunnel.c \
@@ -21,7 +22,8 @@ TRUNNELSOURCES = \
 	src/trunnel/hs/cell_establish_intro.c	\
 	src/trunnel/hs/cell_introduce1.c \
 	src/trunnel/hs/cell_rendezvous.c \
-	src/trunnel/channelpadding_negotiation.c
+	src/trunnel/channelpadding_negotiation.c \
+	src/trunnel/socks5.c
 
 TRUNNELHEADERS = \
 	src/ext/trunnel/trunnel.h		\
@@ -34,7 +36,8 @@ TRUNNELHEADERS = \
 	src/trunnel/hs/cell_establish_intro.h	\
 	src/trunnel/hs/cell_introduce1.h \
 	src/trunnel/hs/cell_rendezvous.h \
-	src/trunnel/channelpadding_negotiation.h
+	src/trunnel/channelpadding_negotiation.h \
+	src/trunnel/socks5.h
 
 src_trunnel_libor_trunnel_a_SOURCES = $(TRUNNELSOURCES)
 src_trunnel_libor_trunnel_a_CPPFLAGS = \

src/trunnel/socks5.c

@@ -0,0 +1,3978 @@
+/* socks5.c -- generated by Trunnel v1.5.2.
+ * https://gitweb.torproject.org/trunnel.git
+ * You probably shouldn't edit this file.
+ */
+#include <stdlib.h>
+#include "trunnel-impl.h"
+
+#include "socks5.h"
+
+#define TRUNNEL_SET_ERROR_CODE(obj) \
+  do {                              \
+    (obj)->trunnel_error_code_ = 1; \
+  } while (0)
+
+#if defined(__COVERITY__) || defined(__clang_analyzer__)
+/* If we're running a static analysis tool, we don't want it to complain
+ * that some of our remaining-bytes checks are dead-code. */
+int socks_deadcode_dummy__ = 0;
+#define OR_DEADCODE_DUMMY || socks_deadcode_dummy__
+#else
+#define OR_DEADCODE_DUMMY
+#endif
+
+#define CHECK_REMAINING(nbytes, label)                           \
+  do {                                                           \
+    if (remaining < (nbytes) OR_DEADCODE_DUMMY) {                \
+      goto label;                                                \
+    }                                                            \
+  } while (0)
+
+domainname_t *
+domainname_new(void)
+{
+  domainname_t *val = trunnel_calloc(1, sizeof(domainname_t));
+  if (NULL == val)
+    return NULL;
+  return val;
+}
+
+/** Release all storage held inside 'obj', but do not free 'obj'.
+ */
+static void
+domainname_clear(domainname_t *obj)
+{
+  (void) obj;
+  TRUNNEL_DYNARRAY_WIPE(&obj->name);
+  TRUNNEL_DYNARRAY_CLEAR(&obj->name);
+}
+
+void
+domainname_free(domainname_t *obj)
+{
+  if (obj == NULL)
+    return;
+  domainname_clear(obj);
+  trunnel_memwipe(obj, sizeof(domainname_t));
+  trunnel_free_(obj);
+}
+
+uint8_t
+domainname_get_len(const domainname_t *inp)
+{
+  return inp->len;
+}
+int
+domainname_set_len(domainname_t *inp, uint8_t val)
+{
+  inp->len = val;
+  return 0;
+}
+size_t
+domainname_getlen_name(const domainname_t *inp)
+{
+  return TRUNNEL_DYNARRAY_LEN(&inp->name);
+}
+
+char
+domainname_get_name(domainname_t *inp, size_t idx)
+{
+  return TRUNNEL_DYNARRAY_GET(&inp->name, idx);
+}
+
+char
+domainname_getconst_name(const domainname_t *inp, size_t idx)
+{
+  return domainname_get_name((domainname_t*)inp, idx);
+}
+int
+domainname_set_name(domainname_t *inp, size_t idx, char elt)
+{
+  TRUNNEL_DYNARRAY_SET(&inp->name, idx, elt);
+  return 0;
+}
+int
+domainname_add_name(domainname_t *inp, char elt)
+{
+#if SIZE_MAX >= UINT8_MAX
+  if (inp->name.n_ == UINT8_MAX)
+    goto trunnel_alloc_failed;
+#endif
+  TRUNNEL_DYNARRAY_ADD(char, &inp->name, elt, {});
+  return 0;
+ trunnel_alloc_failed:
+  TRUNNEL_SET_ERROR_CODE(inp);
+  return -1;
+}
+
+char *
+domainname_getarray_name(domainname_t *inp)
+{
+  return inp->name.elts_;
+}
+const char  *
+domainname_getconstarray_name(const domainname_t *inp)
+{
+  return (const char  *)domainname_getarray_name((domainname_t*)inp);
+}
+int
+domainname_setlen_name(domainname_t *inp, size_t newlen)
+{
+#if UINT8_MAX < SIZE_MAX
+  if (newlen > UINT8_MAX)
+    goto trunnel_alloc_failed;
+#endif
+  return trunnel_string_setlen(&inp->name, newlen,
+            &inp->trunnel_error_code_);
+ trunnel_alloc_failed:
+  TRUNNEL_SET_ERROR_CODE(inp);
+  return -1;
+}
+const char *
+domainname_getstr_name(domainname_t *inp)
+{
+  return trunnel_string_getstr(&inp->name);
+}
+int
+domainname_setstr0_name(domainname_t *inp, const char *val, size_t len)
+{
+#if UINT8_MAX < SIZE_MAX
+  if (len > UINT8_MAX) {
+    TRUNNEL_SET_ERROR_CODE(inp);
+    return -1;
+  }
+#endif
+  return trunnel_string_setstr0(&inp->name, val, len, &inp->trunnel_error_code_);
+}
+int
+domainname_setstr_name(domainname_t *inp, const char *val)
+{
+  return domainname_setstr0_name(inp, val, strlen(val));
+}
+const char *
+domainname_check(const domainname_t *obj)
+{
+  if (obj == NULL)
+    return "Object was NULL";
+  if (obj->trunnel_error_code_)
+    return "A set function failed on this object";
+  if (TRUNNEL_DYNARRAY_LEN(&obj->name) != obj->len)
+    return "Length mismatch for name";
+  return NULL;
+}
+
+ssize_t
+domainname_encoded_len(const domainname_t *obj)
+{
+  ssize_t result = 0;
+
+  if (NULL != domainname_check(obj))
+     return -1;
+
+
+  /* Length of u8 len */
+  result += 1;
+
+  /* Length of char name[len] */
+  result += TRUNNEL_DYNARRAY_LEN(&obj->name);
+  return result;
+}
+int
+domainname_clear_errors(domainname_t *obj)
+{
+  int r = obj->trunnel_error_code_;
+  obj->trunnel_error_code_ = 0;
+  return r;
+}
+ssize_t
+domainname_encode(uint8_t *output, const size_t avail, const domainname_t *obj)
+{
+  ssize_t result = 0;
+  size_t written = 0;
+  uint8_t *ptr = output;
+  const char *msg;
+#ifdef TRUNNEL_CHECK_ENCODED_LEN
+  const ssize_t encoded_len = domainname_encoded_len(obj);
+#endif
+
+  if (NULL != (msg = domainname_check(obj)))
+    goto check_failed;
+
+#ifdef TRUNNEL_CHECK_ENCODED_LEN
+  trunnel_assert(encoded_len >= 0);
+#endif
+
+  /* Encode u8 len */
+  trunnel_assert(written <= avail);
+  if (avail - written < 1)
+    goto truncated;
+  trunnel_set_uint8(ptr, (obj->len));
+  written += 1; ptr += 1;
+
+  /* Encode char name[len] */
+  {
+    size_t elt_len = TRUNNEL_DYNARRAY_LEN(&obj->name);
+    trunnel_assert(obj->len == elt_len);
+    trunnel_assert(written <= avail);
+    if (avail - written < elt_len)
+      goto truncated;
+    if (elt_len)
+      memcpy(ptr, obj->name.elts_, elt_len);
+    written += elt_len; ptr += elt_len;
+  }
+
+
+  trunnel_assert(ptr == output + written);
+#ifdef TRUNNEL_CHECK_ENCODED_LEN
+  {
+    trunnel_assert(encoded_len >= 0);
+    trunnel_assert((size_t)encoded_len == written);
+  }
+
+#endif
+
+  return written;
+
+ truncated:
+  result = -2;
+  goto fail;
+ check_failed:
+  (void)msg;
+  result = -1;
+  goto fail;
+ fail:
+  trunnel_assert(result < 0);
+  return result;
+}
+
+/** As domainname_parse(), but do not allocate the output object.
+ */
+static ssize_t
+domainname_parse_into(domainname_t *obj, const uint8_t *input, const size_t len_in)
+{
+  const uint8_t *ptr = input;
+  size_t remaining = len_in;
+  ssize_t result = 0;
+  (void)result;
+
+  /* Parse u8 len */
+  CHECK_REMAINING(1, truncated);
+  obj->len = (trunnel_get_uint8(ptr));
+  remaining -= 1; ptr += 1;
+
+  /* Parse char name[len] */
+  CHECK_REMAINING(obj->len, truncated);
+  if (domainname_setstr0_name(obj, (const char*)ptr, obj->len))
+    goto fail;
+  ptr += obj->len; remaining -= obj->len;
+  trunnel_assert(ptr + remaining == input + len_in);
+  return len_in - remaining;
+
+ truncated:
+  return -2;
+ fail:
+  result = -1;
+  return result;
+}
+
+ssize_t
+domainname_parse(domainname_t **output, const uint8_t *input, const size_t len_in)
+{
+  ssize_t result;
+  *output = domainname_new();
+  if (NULL == *output)
+    return -1;
+  result = domainname_parse_into(*output, input, len_in);
+  if (result < 0) {
+    domainname_free(*output);
+    *output = NULL;
+  }
+  return result;
+}
+socks4_client_request_t *
+socks4_client_request_new(void)
+{
+  socks4_client_request_t *val = trunnel_calloc(1, sizeof(socks4_client_request_t));
+  if (NULL == val)
+    return NULL;
+  val->version = 4;
+  val->command = CMD_BIND;
+  return val;
+}
+
+/** Release all storage held inside 'obj', but do not free 'obj'.
+ */
+static void
+socks4_client_request_clear(socks4_client_request_t *obj)
+{
+  (void) obj;
+  trunnel_wipestr(obj->username);
+  trunnel_free(obj->username);
+  trunnel_wipestr(obj->socks4a_addr_hostname);
+  trunnel_free(obj->socks4a_addr_hostname);
+}
+
+void
+socks4_client_request_free(socks4_client_request_t *obj)
+{
+  if (obj == NULL)
+    return;
+  socks4_client_request_clear(obj);
+  trunnel_memwipe(obj, sizeof(socks4_client_request_t));
+  trunnel_free_(obj);
+}
+
+uint8_t
+socks4_client_request_get_version(const socks4_client_request_t *inp)
+{
+  return inp->version;
+}
+int
+socks4_client_request_set_version(socks4_client_request_t *inp, uint8_t val)
+{
+  if (! ((val == 4))) {
+     TRUNNEL_SET_ERROR_CODE(inp);
+     return -1;
+  }
+  inp->version = val;
+  return 0;
+}
+uint8_t
+socks4_client_request_get_command(const socks4_client_request_t *inp)
+{
+  return inp->command;
+}
+int
+socks4_client_request_set_command(socks4_client_request_t *inp, uint8_t val)
+{
+  if (! ((val == CMD_BIND || val == CMD_CONNECT || val == CMD_RESOLVE || val == CMD_RESOLVE_PTR))) {
+     TRUNNEL_SET_ERROR_CODE(inp);
+     return -1;
+  }
+  inp->command = val;
+  return 0;
+}
+uint16_t
+socks4_client_request_get_port(const socks4_client_request_t *inp)
+{
+  return inp->port;
+}
+int
+socks4_client_request_set_port(socks4_client_request_t *inp, uint16_t val)
+{
+  inp->port = val;
+  return 0;
+}
+uint32_t
+socks4_client_request_get_addr(const socks4_client_request_t *inp)
+{
+  return inp->addr;
+}
+int
+socks4_client_request_set_addr(socks4_client_request_t *inp, uint32_t val)
+{
+  inp->addr = val;
+  return 0;
+}
+const char *
+socks4_client_request_get_username(const socks4_client_request_t *inp)
+{
+  return inp->username;
+}
+int
+socks4_client_request_set_username(socks4_client_request_t *inp, const char *val)
+{
+  trunnel_free(inp->username);
+  if (NULL == (inp->username = trunnel_strdup(val))) {
+    TRUNNEL_SET_ERROR_CODE(inp);
+    return -1;
+  }
+  return 0;
+}
+const char *
+socks4_client_request_get_socks4a_addr_hostname(const socks4_client_request_t *inp)
+{
+  return inp->socks4a_addr_hostname;
+}
+int
+socks4_client_request_set_socks4a_addr_hostname(socks4_client_request_t *inp, const char *val)
+{
+  trunnel_free(inp->socks4a_addr_hostname);
+  if (NULL == (inp->socks4a_addr_hostname = trunnel_strdup(val))) {
+    TRUNNEL_SET_ERROR_CODE(inp);
+    return -1;
+  }
+  return 0;
+}
+const char *
+socks4_client_request_check(const socks4_client_request_t *obj)
+{
+  if (obj == NULL)
+    return "Object was NULL";
+  if (obj->trunnel_error_code_)
+    return "A set function failed on this object";
+  if (! (obj->version == 4))
+    return "Integer out of bounds";
+  if (! (obj->command == CMD_BIND || obj->command == CMD_CONNECT || obj->command == CMD_RESOLVE || obj->command == CMD_RESOLVE_PTR))
+    return "Integer out of bounds";
+  if (NULL == obj->username)
+    return "Missing username";
+  switch (obj->addr) {
+
+    case 1:
+    case 2:
+    case 3:
+    case 4:
+    case 5:
+    case 6:
+    case 7:
+    case 8:
+    case 9:
+    case 10:
+    case 11:
+    case 12:
+    case 13:
+    case 14:
+    case 15:
+    case 16:
+    case 17:
+    case 18:
+    case 19:
+    case 20:
+    case 21:
+    case 22:
+    case 23:
+    case 24:
+    case 25:
+    case 26:
+    case 27:
+    case 28:
+    case 29:
+    case 30:
+    case 31:
+    case 32:
+    case 33:
+    case 34:
+    case 35:
+    case 36:
+    case 37:
+    case 38:
+    case 39:
+    case 40:
+    case 41:
+    case 42:
+    case 43:
+    case 44:
+    case 45:
+    case 46:
+    case 47:
+    case 48:
+    case 49:
+    case 50:
+    case 51:
+    case 52:
+    case 53:
+    case 54:
+    case 55:
+    case 56:
+    case 57:
+    case 58:
+    case 59:
+    case 60:
+    case 61:
+    case 62:
+    case 63:
+    case 64:
+    case 65:
+    case 66:
+    case 67:
+    case 68:
+    case 69:
+    case 70:
+    case 71:
+    case 72:
+    case 73:
+    case 74:
+    case 75:
+    case 76:
+    case 77:
+    case 78:
+    case 79:
+    case 80:
+    case 81:
+    case 82:
+    case 83:
+    case 84:
+    case 85:
+    case 86:
+    case 87:
+    case 88:
+    case 89:
+    case 90:
+    case 91:
+    case 92:
+    case 93:
+    case 94:
+    case 95:
+    case 96:
+    case 97:
+    case 98:
+    case 99:
+    case 100:
+    case 101:
+    case 102:
+    case 103:
+    case 104:
+    case 105:
+    case 106:
+    case 107:
+    case 108:
+    case 109:
+    case 110:
+    case 111:
+    case 112:
+    case 113:
+    case 114:
+    case 115:
+    case 116:
+    case 117:
+    case 118:
+    case 119:
+    case 120:
+    case 121:
+    case 122:
+    case 123:
+    case 124:
+    case 125:
+    case 126:
+    case 127:
+    case 128:
+    case 129:
+    case 130:
+    case 131:
+    case 132:
+    case 133:
+    case 134:
+    case 135:
+    case 136:
+    case 137:
+    case 138:
+    case 139:
+    case 140:
+    case 141:
+    case 142:
+    case 143:
+    case 144:
+    case 145:
+    case 146:
+    case 147:
+    case 148:
+    case 149:
+    case 150:
+    case 151:
+    case 152:
+    case 153:
+    case 154:
+    case 155:
+    case 156:
+    case 157:
+    case 158:
+    case 159:
+    case 160:
+    case 161:
+    case 162:
+    case 163:
+    case 164:
+    case 165:
+    case 166:
+    case 167:
+    case 168:
+    case 169:
+    case 170:
+    case 171:
+    case 172:
+    case 173:
+    case 174:
+    case 175:
+    case 176:
+    case 177:
+    case 178:
+    case 179:
+    case 180:
+    case 181:
+    case 182:
+    case 183:
+    case 184:
+    case 185:
+    case 186:
+    case 187:
+    case 188:
+    case 189:
+    case 190:
+    case 191:
+    case 192:
+    case 193:
+    case 194:
+    case 195:
+    case 196:
+    case 197:
+    case 198:
+    case 199:
+    case 200:
+    case 201:
+    case 202:
+    case 203:
+    case 204:
+    case 205:
+    case 206:
+    case 207:
+    case 208:
+    case 209:
+    case 210:
+    case 211:
+    case 212:
+    case 213:
+    case 214:
+    case 215:
+    case 216:
+    case 217:
+    case 218:
+    case 219:
+    case 220:
+    case 221:
+    case 222:
+    case 223:
+    case 224:
+    case 225:
+    case 226:
+    case 227:
+    case 228:
+    case 229:
+    case 230:
+    case 231:
+    case 232:
+    case 233:
+    case 234:
+    case 235:
+    case 236:
+    case 237:
+    case 238:
+    case 239:
+    case 240:
+    case 241:
+    case 242:
+    case 243:
+    case 244:
+    case 245:
+    case 246:
+    case 247:
+    case 248:
+    case 249:
+    case 250:
+    case 251:
+    case 252:
+    case 253:
+    case 254:
+    case 255:
+      if (NULL == obj->socks4a_addr_hostname)
+        return "Missing socks4a_addr_hostname";
+      break;
+
+    default:
+      break;
+  }
+  return NULL;
+}
+
+ssize_t
+socks4_client_request_encoded_len(const socks4_client_request_t *obj)
+{
+  ssize_t result = 0;
+
+  if (NULL != socks4_client_request_check(obj))
+     return -1;
+
+
+  /* Length of u8 version IN [4] */
+  result += 1;
+
+  /* Length of u8 command IN [CMD_BIND, CMD_CONNECT, CMD_RESOLVE, CMD_RESOLVE_PTR] */
+  result += 1;
+
+  /* Length of u16 port */
+  result += 2;
+
+  /* Length of u32 addr */
+  result += 4;
+
+  /* Length of nulterm username */
+  result += strlen(obj->username) + 1;
+  switch (obj->addr) {
+
+    case 1:
+    case 2:
+    case 3:
+    case 4:
+    case 5:
+    case 6:
+    case 7:
+    case 8:
+    case 9:
+    case 10:
+    case 11:
+    case 12:
+    case 13:
+    case 14:
+    case 15:
+    case 16:
+    case 17:
+    case 18:
+    case 19:
+    case 20:
+    case 21:
+    case 22:
+    case 23:
+    case 24:
+    case 25:
+    case 26:
+    case 27:
+    case 28:
+    case 29:
+    case 30:
+    case 31:
+    case 32:
+    case 33:
+    case 34:
+    case 35:
+    case 36:
+    case 37:
+    case 38:
+    case 39:
+    case 40:
+    case 41:
+    case 42:
+    case 43:
+    case 44:
+    case 45:
+    case 46:
+    case 47:
+    case 48:
+    case 49:
+    case 50:
+    case 51:
+    case 52:
+    case 53:
+    case 54:
+    case 55:
+    case 56:
+    case 57:
+    case 58:
+    case 59:
+    case 60:
+    case 61:
+    case 62:
+    case 63:
+    case 64:
+    case 65:
+    case 66:
+    case 67:
+    case 68:
+    case 69:
+    case 70:
+    case 71:
+    case 72:
+    case 73:
+    case 74:
+    case 75:
+    case 76:
+    case 77:
+    case 78:
+    case 79:
+    case 80:
+    case 81:
+    case 82:
+    case 83:
+    case 84:
+    case 85:
+    case 86:
+    case 87:
+    case 88:
+    case 89:
+    case 90:
+    case 91:
+    case 92:
+    case 93:
+    case 94:
+    case 95:
+    case 96:
+    case 97:
+    case 98:
+    case 99:
+    case 100:
+    case 101:
+    case 102:
+    case 103:
+    case 104:
+    case 105:
+    case 106:
+    case 107:
+    case 108:
+    case 109:
+    case 110:
+    case 111:
+    case 112:
+    case 113:
+    case 114:
+    case 115:
+    case 116:
+    case 117:
+    case 118:
+    case 119:
+    case 120:
+    case 121:
+    case 122:
+    case 123:
+    case 124:
+    case 125:
+    case 126:
+    case 127:
+    case 128:
+    case 129:
+    case 130:
+    case 131:
+    case 132:
+    case 133:
+    case 134:
+    case 135:
+    case 136:
+    case 137:
+    case 138:
+    case 139:
+    case 140:
+    case 141:
+    case 142:
+    case 143:
+    case 144:
+    case 145:
+    case 146:
+    case 147:
+    case 148:
+    case 149:
+    case 150:
+    case 151:
+    case 152:
+    case 153:
+    case 154:
+    case 155:
+    case 156:
+    case 157:
+    case 158:
+    case 159:
+    case 160:
+    case 161:
+    case 162:
+    case 163:
+    case 164:
+    case 165:
+    case 166:
+    case 167:
+    case 168:
+    case 169:
+    case 170:
+    case 171:
+    case 172:
+    case 173:
+    case 174:
+    case 175:
+    case 176:
+    case 177:
+    case 178:
+    case 179:
+    case 180:
+    case 181:
+    case 182:
+    case 183:
+    case 184:
+    case 185:
+    case 186:
+    case 187:
+    case 188:
+    case 189:
+    case 190:
+    case 191:
+    case 192:
+    case 193:
+    case 194:
+    case 195:
+    case 196:
+    case 197:
+    case 198:
+    case 199:
+    case 200:
+    case 201:
+    case 202:
+    case 203:
+    case 204:
+    case 205:
+    case 206:
+    case 207:
+    case 208:
+    case 209:
+    case 210:
+    case 211:
+    case 212:
+    case 213:
+    case 214:
+    case 215:
+    case 216:
+    case 217:
+    case 218:
+    case 219:
+    case 220:
+    case 221:
+    case 222:
+    case 223:
+    case 224:
+    case 225:
+    case 226:
+    case 227:
+    case 228:
+    case 229:
+    case 230:
+    case 231:
+    case 232:
+    case 233:
+    case 234:
+    case 235:
+    case 236:
+    case 237:
+    case 238:
+    case 239:
+    case 240:
+    case 241:
+    case 242:
+    case 243:
+    case 244:
+    case 245:
+    case 246:
+    case 247:
+    case 248:
+    case 249:
+    case 250:
+    case 251:
+    case 252:
+    case 253:
+    case 254:
+    case 255:
+
+      /* Length of nulterm socks4a_addr_hostname */
+      result += strlen(obj->socks4a_addr_hostname) + 1;
+      break;
+
+    default:
+      break;
+  }
+  return result;
+}
+int
+socks4_client_request_clear_errors(socks4_client_request_t *obj)
+{
+  int r = obj->trunnel_error_code_;
+  obj->trunnel_error_code_ = 0;
+  return r;
+}
+ssize_t
+socks4_client_request_encode(uint8_t *output, const size_t avail, const socks4_client_request_t *obj)
+{
+  ssize_t result = 0;
+  size_t written = 0;
+  uint8_t *ptr = output;
+  const char *msg;
+#ifdef TRUNNEL_CHECK_ENCODED_LEN
+  const ssize_t encoded_len = socks4_client_request_encoded_len(obj);
+#endif
+
+  if (NULL != (msg = socks4_client_request_check(obj)))
+    goto check_failed;
+
+#ifdef TRUNNEL_CHECK_ENCODED_LEN
+  trunnel_assert(encoded_len >= 0);
+#endif
+
+  /* Encode u8 version IN [4] */
+  trunnel_assert(written <= avail);
+  if (avail - written < 1)
+    goto truncated;
+  trunnel_set_uint8(ptr, (obj->version));
+  written += 1; ptr += 1;
+
+  /* Encode u8 command IN [CMD_BIND, CMD_CONNECT, CMD_RESOLVE, CMD_RESOLVE_PTR] */
+  trunnel_assert(written <= avail);
+  if (avail - written < 1)
+    goto truncated;
+  trunnel_set_uint8(ptr, (obj->command));
+  written += 1; ptr += 1;
+
+  /* Encode u16 port */
+  trunnel_assert(written <= avail);
+  if (avail - written < 2)
+    goto truncated;
+  trunnel_set_uint16(ptr, trunnel_htons(obj->port));
+  written += 2; ptr += 2;
+
+  /* Encode u32 addr */
+  trunnel_assert(written <= avail);
+  if (avail - written < 4)
+    goto truncated;
+  trunnel_set_uint32(ptr, trunnel_htonl(obj->addr));
+  written += 4; ptr += 4;
+
+  /* Encode nulterm username */
+  {
+    size_t len = strlen(obj->username);
+    trunnel_assert(written <= avail);
+    if (avail - written < len + 1)
+      goto truncated;
+    memcpy(ptr, obj->username, len + 1);
+    ptr += len + 1; written += len + 1;
+  }
+
+  /* Encode union socks4a_addr[addr] */
+  trunnel_assert(written <= avail);
+  switch (obj->addr) {
+
+    case 1:
+    case 2:
+    case 3:
+    case 4:
+    case 5:
+    case 6:
+    case 7:
+    case 8:
+    case 9:
+    case 10:
+    case 11:
+    case 12:
+    case 13:
+    case 14:
+    case 15:
+    case 16:
+    case 17:
+    case 18:
+    case 19:
+    case 20:
+    case 21:
+    case 22:
+    case 23:
+    case 24:
+    case 25:
+    case 26:
+    case 27:
+    case 28:
+    case 29:
+    case 30:
+    case 31:
+    case 32:
+    case 33:
+    case 34:
+    case 35:
+    case 36:
+    case 37:
+    case 38:
+    case 39:
+    case 40:
+    case 41:
+    case 42:
+    case 43:
+    case 44:
+    case 45:
+    case 46:
+    case 47:
+    case 48:
+    case 49:
+    case 50:
+    case 51:
+    case 52:
+    case 53:
+    case 54:
+    case 55:
+    case 56:
+    case 57:
+    case 58:
+    case 59:
+    case 60:
+    case 61:
+    case 62:
+    case 63:
+    case 64:
+    case 65:
+    case 66:
+    case 67:
+    case 68:
+    case 69:
+    case 70:
+    case 71:
+    case 72:
+    case 73:
+    case 74:
+    case 75:
+    case 76:
+    case 77:
+    case 78:
+    case 79:
+    case 80:
+    case 81:
+    case 82:
+    case 83:
+    case 84:
+    case 85:
+    case 86:
+    case 87:
+    case 88:
+    case 89:
+    case 90:
+    case 91:
+    case 92:
+    case 93:
+    case 94:
+    case 95:
+    case 96:
+    case 97:
+    case 98:
+    case 99:
+    case 100:
+    case 101:
+    case 102:
+    case 103:
+    case 104:
+    case 105:
+    case 106:
+    case 107:
+    case 108:
+    case 109:
+    case 110:
+    case 111:
+    case 112:
+    case 113:
+    case 114:
+    case 115:
+    case 116:
+    case 117:
+    case 118:
+    case 119:
+    case 120:
+    case 121:
+    case 122:
+    case 123:
+    case 124:
+    case 125:
+    case 126:
+    case 127:
+    case 128:
+    case 129:
+    case 130:
+    case 131:
+    case 132:
+    case 133:
+    case 134:
+    case 135:
+    case 136:
+    case 137:
+    case 138:
+    case 139:
+    case 140:
+    case 141:
+    case 142:
+    case 143:
+    case 144:
+    case 145:
+    case 146:
+    case 147:
+    case 148:
+    case 149:
+    case 150:
+    case 151:
+    case 152:
+    case 153:
+    case 154:
+    case 155:
+    case 156:
+    case 157:
+    case 158:
+    case 159:
+    case 160:
+    case 161:
+    case 162:
+    case 163:
+    case 164:
+    case 165:
+    case 166:
+    case 167:
+    case 168:
+    case 169:
+    case 170:
+    case 171:
+    case 172:
+    case 173:
+    case 174:
+    case 175:
+    case 176:
+    case 177:
+    case 178:
+    case 179:
+    case 180:
+    case 181:
+    case 182:
+    case 183:
+    case 184:
+    case 185:
+    case 186:
+    case 187:
+    case 188:
+    case 189:
+    case 190:
+    case 191:
+    case 192:
+    case 193:
+    case 194:
+    case 195:
+    case 196:
+    case 197:
+    case 198:
+    case 199:
+    case 200:
+    case 201:
+    case 202:
+    case 203:
+    case 204:
+    case 205:
+    case 206:
+    case 207:
+    case 208:
+    case 209:
+    case 210:
+    case 211:
+    case 212:
+    case 213:
+    case 214:
+    case 215:
+    case 216:
+    case 217:
+    case 218:
+    case 219:
+    case 220:
+    case 221:
+    case 222:
+    case 223:
+    case 224:
+    case 225:
+    case 226:
+    case 227:
+    case 228:
+    case 229:
+    case 230:
+    case 231:
+    case 232:
+    case 233:
+    case 234:
+    case 235:
+    case 236:
+    case 237:
+    case 238:
+    case 239:
+    case 240:
+    case 241:
+    case 242:
+    case 243:
+    case 244:
+    case 245:
+    case 246:
+    case 247:
+    case 248:
+    case 249:
+    case 250:
+    case 251:
+    case 252:
+    case 253:
+    case 254:
+    case 255:
+
+      /* Encode nulterm socks4a_addr_hostname */
+      {
+        size_t len = strlen(obj->socks4a_addr_hostname);
+        trunnel_assert(written <= avail);
+        if (avail - written < len + 1)
+          goto truncated;
+        memcpy(ptr, obj->socks4a_addr_hostname, len + 1);
+        ptr += len + 1; written += len + 1;
+      }
+      break;
+
+    default:
+      break;
+  }
+
+
+  trunnel_assert(ptr == output + written);
+#ifdef TRUNNEL_CHECK_ENCODED_LEN
+  {
+    trunnel_assert(encoded_len >= 0);
+    trunnel_assert((size_t)encoded_len == written);
+  }
+
+#endif
+
+  return written;
+
+ truncated:
+  result = -2;
+  goto fail;
+ check_failed:
+  (void)msg;
+  result = -1;
+  goto fail;
+ fail:
+  trunnel_assert(result < 0);
+  return result;
+}
+
+/** As socks4_client_request_parse(), but do not allocate the output
+ * object.
+ */
+static ssize_t
+socks4_client_request_parse_into(socks4_client_request_t *obj, const uint8_t *input, const size_t len_in)
+{
+  const uint8_t *ptr = input;
+  size_t remaining = len_in;
+  ssize_t result = 0;
+  (void)result;
+
+  /* Parse u8 version IN [4] */
+  CHECK_REMAINING(1, truncated);
+  obj->version = (trunnel_get_uint8(ptr));
+  remaining -= 1; ptr += 1;
+  if (! (obj->version == 4))
+    goto fail;
+
+  /* Parse u8 command IN [CMD_BIND, CMD_CONNECT, CMD_RESOLVE, CMD_RESOLVE_PTR] */
+  CHECK_REMAINING(1, truncated);
+  obj->command = (trunnel_get_uint8(ptr));
+  remaining -= 1; ptr += 1;
+  if (! (obj->command == CMD_BIND || obj->command == CMD_CONNECT || obj->command == CMD_RESOLVE || obj->command == CMD_RESOLVE_PTR))
+    goto fail;
+
+  /* Parse u16 port */
+  CHECK_REMAINING(2, truncated);
+  obj->port = trunnel_ntohs(trunnel_get_uint16(ptr));
+  remaining -= 2; ptr += 2;
+
+  /* Parse u32 addr */
+  CHECK_REMAINING(4, truncated);
+  obj->addr = trunnel_ntohl(trunnel_get_uint32(ptr));
+  remaining -= 4; ptr += 4;
+
+  /* Parse nulterm username */
+  {
+    uint8_t *eos = (uint8_t*)memchr(ptr, 0, remaining);
+    size_t memlen;
+    if (eos == NULL)
+      goto truncated;
+    trunnel_assert(eos >= ptr);
+    trunnel_assert((size_t)(eos - ptr) < SIZE_MAX - 1);
+    memlen = ((size_t)(eos - ptr)) + 1;
+    if (!(obj->username = trunnel_malloc(memlen)))
+      goto fail;
+    memcpy(obj->username, ptr, memlen);
+    remaining -= memlen; ptr += memlen;
+  }
+
+  /* Parse union socks4a_addr[addr] */
+  switch (obj->addr) {
+
+    case 1:
+    case 2:
+    case 3:
+    case 4:
+    case 5:
+    case 6:
+    case 7:
+    case 8:
+    case 9:
+    case 10:
+    case 11:
+    case 12:
+    case 13:
+    case 14:
+    case 15:
+    case 16:
+    case 17:
+    case 18:
+    case 19:
+    case 20:
+    case 21:
+    case 22:
+    case 23:
+    case 24:
+    case 25:
+    case 26:
+    case 27:
+    case 28:
+    case 29:
+    case 30:
+    case 31:
+    case 32:
+    case 33:
+    case 34:
+    case 35:
+    case 36:
+    case 37:
+    case 38:
+    case 39:
+    case 40:
+    case 41:
+    case 42:
+    case 43:
+    case 44:
+    case 45:
+    case 46:
+    case 47:
+    case 48:
+    case 49:
+    case 50:
+    case 51:
+    case 52:
+    case 53:
+    case 54:
+    case 55:
+    case 56:
+    case 57:
+    case 58:
+    case 59:
+    case 60:
+    case 61:
+    case 62:
+    case 63:
+    case 64:
+    case 65:
+    case 66:
+    case 67:
+    case 68:
+    case 69:
+    case 70:
+    case 71:
+    case 72:
+    case 73:
+    case 74:
+    case 75:
+    case 76:
+    case 77:
+    case 78:
+    case 79:
+    case 80:
+    case 81:
+    case 82:
+    case 83:
+    case 84:
+    case 85:
+    case 86:
+    case 87:
+    case 88:
+    case 89:
+    case 90:
+    case 91:
+    case 92:
+    case 93:
+    case 94:
+    case 95:
+    case 96:
+    case 97:
+    case 98:
+    case 99:
+    case 100:
+    case 101:
+    case 102:
+    case 103:
+    case 104:
+    case 105:
+    case 106:
+    case 107:
+    case 108:
+    case 109:
+    case 110:
+    case 111:
+    case 112:
+    case 113:
+    case 114:
+    case 115:
+    case 116:
+    case 117:
+    case 118:
+    case 119:
+    case 120:
+    case 121:
+    case 122:
+    case 123:
+    case 124:
+    case 125:
+    case 126:
+    case 127:
+    case 128:
+    case 129:
+    case 130:
+    case 131:
+    case 132:
+    case 133:
+    case 134:
+    case 135:
+    case 136:
+    case 137:
+    case 138:
+    case 139:
+    case 140:
+    case 141:
+    case 142:
+    case 143:
+    case 144:
+    case 145:
+    case 146:
+    case 147:
+    case 148:
+    case 149:
+    case 150:
+    case 151:
+    case 152:
+    case 153:
+    case 154:
+    case 155:
+    case 156:
+    case 157:
+    case 158:
+    case 159:
+    case 160:
+    case 161:
+    case 162:
+    case 163:
+    case 164:
+    case 165:
+    case 166:
+    case 167:
+    case 168:
+    case 169:
+    case 170:
+    case 171:
+    case 172:
+    case 173:
+    case 174:
+    case 175:
+    case 176:
+    case 177:
+    case 178:
+    case 179:
+    case 180:
+    case 181:
+    case 182:
+    case 183:
+    case 184:
+    case 185:
+    case 186:
+    case 187:
+    case 188:
+    case 189:
+    case 190:
+    case 191:
+    case 192:
+    case 193:
+    case 194:
+    case 195:
+    case 196:
+    case 197:
+    case 198:
+    case 199:
+    case 200:
+    case 201:
+    case 202:
+    case 203:
+    case 204:
+    case 205:
+    case 206:
+    case 207:
+    case 208:
+    case 209:
+    case 210:
+    case 211:
+    case 212:
+    case 213:
+    case 214:
+    case 215:
+    case 216:
+    case 217:
+    case 218:
+    case 219:
+    case 220:
+    case 221:
+    case 222:
+    case 223:
+    case 224:
+    case 225:
+    case 226:
+    case 227:
+    case 228:
+    case 229:
+    case 230:
+    case 231:
+    case 232:
+    case 233:
+    case 234:
+    case 235:
+    case 236:
+    case 237:
+    case 238:
+    case 239:
+    case 240:
+    case 241:
+    case 242:
+    case 243:
+    case 244:
+    case 245:
+    case 246:
+    case 247:
+    case 248:
+    case 249:
+    case 250:
+    case 251:
+    case 252:
+    case 253:
+    case 254:
+    case 255:
+
+      /* Parse nulterm socks4a_addr_hostname */
+      {
+        uint8_t *eos = (uint8_t*)memchr(ptr, 0, remaining);
+        size_t memlen;
+        if (eos == NULL)
+          goto truncated;
+        trunnel_assert(eos >= ptr);
+        trunnel_assert((size_t)(eos - ptr) < SIZE_MAX - 1);
+        memlen = ((size_t)(eos - ptr)) + 1;
+        if (!(obj->socks4a_addr_hostname = trunnel_malloc(memlen)))
+          goto fail;
+        memcpy(obj->socks4a_addr_hostname, ptr, memlen);
+        remaining -= memlen; ptr += memlen;
+      }
+      break;
+
+    default:
+      break;
+  }
+  trunnel_assert(ptr + remaining == input + len_in);
+  return len_in - remaining;
+
+ truncated:
+  return -2;
+ fail:
+  result = -1;
+  return result;
+}
+
+ssize_t
+socks4_client_request_parse(socks4_client_request_t **output, const uint8_t *input, const size_t len_in)
+{
+  ssize_t result;
+  *output = socks4_client_request_new();
+  if (NULL == *output)
+    return -1;
+  result = socks4_client_request_parse_into(*output, input, len_in);
+  if (result < 0) {
+    socks4_client_request_free(*output);
+    *output = NULL;
+  }
+  return result;
+}
+socks4_server_reply_t *
+socks4_server_reply_new(void)
+{
+  socks4_server_reply_t *val = trunnel_calloc(1, sizeof(socks4_server_reply_t));
+  if (NULL == val)
+    return NULL;
+  val->version = 4;
+  return val;
+}
+
+/** Release all storage held inside 'obj', but do not free 'obj'.
+ */
+static void
+socks4_server_reply_clear(socks4_server_reply_t *obj)
+{
+  (void) obj;
+}
+
+void
+socks4_server_reply_free(socks4_server_reply_t *obj)
+{
+  if (obj == NULL)
+    return;
+  socks4_server_reply_clear(obj);
+  trunnel_memwipe(obj, sizeof(socks4_server_reply_t));
+  trunnel_free_(obj);
+}
+
+uint8_t
+socks4_server_reply_get_version(const socks4_server_reply_t *inp)
+{
+  return inp->version;
+}
+int
+socks4_server_reply_set_version(socks4_server_reply_t *inp, uint8_t val)
+{
+  if (! ((val == 4))) {
+     TRUNNEL_SET_ERROR_CODE(inp);
+     return -1;
+  }
+  inp->version = val;
+  return 0;
+}
+uint8_t
+socks4_server_reply_get_status(const socks4_server_reply_t *inp)
+{
+  return inp->status;
+}
+int
+socks4_server_reply_set_status(socks4_server_reply_t *inp, uint8_t val)
+{
+  inp->status = val;
+  return 0;
+}
+uint16_t
+socks4_server_reply_get_port(const socks4_server_reply_t *inp)
+{
+  return inp->port;
+}
+int
+socks4_server_reply_set_port(socks4_server_reply_t *inp, uint16_t val)
+{
+  inp->port = val;
+  return 0;
+}
+uint32_t
+socks4_server_reply_get_addr(const socks4_server_reply_t *inp)
+{
+  return inp->addr;
+}
+int
+socks4_server_reply_set_addr(socks4_server_reply_t *inp, uint32_t val)
+{
+  inp->addr = val;
+  return 0;
+}
+const char *
+socks4_server_reply_check(const socks4_server_reply_t *obj)
+{
+  if (obj == NULL)
+    return "Object was NULL";
+  if (obj->trunnel_error_code_)
+    return "A set function failed on this object";
+  if (! (obj->version == 4))
+    return "Integer out of bounds";
+  return NULL;
+}
+
+ssize_t
+socks4_server_reply_encoded_len(const socks4_server_reply_t *obj)
+{
+  ssize_t result = 0;
+
+  if (NULL != socks4_server_reply_check(obj))
+     return -1;
+
+
+  /* Length of u8 version IN [4] */
+  result += 1;
+
+  /* Length of u8 status */
+  result += 1;
+
+  /* Length of u16 port */
+  result += 2;
+
+  /* Length of u32 addr */
+  result += 4;
+  return result;
+}
+int
+socks4_server_reply_clear_errors(socks4_server_reply_t *obj)
+{
+  int r = obj->trunnel_error_code_;
+  obj->trunnel_error_code_ = 0;
+  return r;
+}
+ssize_t
+socks4_server_reply_encode(uint8_t *output, const size_t avail, const socks4_server_reply_t *obj)
+{
+  ssize_t result = 0;
+  size_t written = 0;
+  uint8_t *ptr = output;
+  const char *msg;
+#ifdef TRUNNEL_CHECK_ENCODED_LEN
+  const ssize_t encoded_len = socks4_server_reply_encoded_len(obj);
+#endif
+
+  if (NULL != (msg = socks4_server_reply_check(obj)))
+    goto check_failed;
+
+#ifdef TRUNNEL_CHECK_ENCODED_LEN
+  trunnel_assert(encoded_len >= 0);
+#endif
+
+  /* Encode u8 version IN [4] */
+  trunnel_assert(written <= avail);
+  if (avail - written < 1)
+    goto truncated;
+  trunnel_set_uint8(ptr, (obj->version));
+  written += 1; ptr += 1;
+
+  /* Encode u8 status */
+  trunnel_assert(written <= avail);
+  if (avail - written < 1)
+    goto truncated;
+  trunnel_set_uint8(ptr, (obj->status));
+  written += 1; ptr += 1;
+
+  /* Encode u16 port */
+  trunnel_assert(written <= avail);
+  if (avail - written < 2)
+    goto truncated;
+  trunnel_set_uint16(ptr, trunnel_htons(obj->port));
+  written += 2; ptr += 2;
+
+  /* Encode u32 addr */
+  trunnel_assert(written <= avail);
+  if (avail - written < 4)
+    goto truncated;
+  trunnel_set_uint32(ptr, trunnel_htonl(obj->addr));
+  written += 4; ptr += 4;
+
+
+  trunnel_assert(ptr == output + written);
+#ifdef TRUNNEL_CHECK_ENCODED_LEN
+  {
+    trunnel_assert(encoded_len >= 0);
+    trunnel_assert((size_t)encoded_len == written);
+  }
+
+#endif
+
+  return written;
+
+ truncated:
+  result = -2;
+  goto fail;
+ check_failed:
+  (void)msg;
+  result = -1;
+  goto fail;
+ fail:
+  trunnel_assert(result < 0);
+  return result;
+}
+
+/** As socks4_server_reply_parse(), but do not allocate the output
+ * object.
+ */
+static ssize_t
+socks4_server_reply_parse_into(socks4_server_reply_t *obj, const uint8_t *input, const size_t len_in)
+{
+  const uint8_t *ptr = input;
+  size_t remaining = len_in;
+  ssize_t result = 0;
+  (void)result;
+
+  /* Parse u8 version IN [4] */
+  CHECK_REMAINING(1, truncated);
+  obj->version = (trunnel_get_uint8(ptr));
+  remaining -= 1; ptr += 1;
+  if (! (obj->version == 4))
+    goto fail;
+
+  /* Parse u8 status */
+  CHECK_REMAINING(1, truncated);
+  obj->status = (trunnel_get_uint8(ptr));
+  remaining -= 1; ptr += 1;
+
+  /* Parse u16 port */
+  CHECK_REMAINING(2, truncated);
+  obj->port = trunnel_ntohs(trunnel_get_uint16(ptr));
+  remaining -= 2; ptr += 2;
+
+  /* Parse u32 addr */
+  CHECK_REMAINING(4, truncated);
+  obj->addr = trunnel_ntohl(trunnel_get_uint32(ptr));
+  remaining -= 4; ptr += 4;
+  trunnel_assert(ptr + remaining == input + len_in);
+  return len_in - remaining;
+
+ truncated:
+  return -2;
+ fail:
+  result = -1;
+  return result;
+}
+
+ssize_t
+socks4_server_reply_parse(socks4_server_reply_t **output, const uint8_t *input, const size_t len_in)
+{
+  ssize_t result;
+  *output = socks4_server_reply_new();
+  if (NULL == *output)
+    return -1;
+  result = socks4_server_reply_parse_into(*output, input, len_in);
+  if (result < 0) {
+    socks4_server_reply_free(*output);
+    *output = NULL;
+  }
+  return result;
+}
+socks5_client_userpass_auth_t *
+socks5_client_userpass_auth_new(void)
+{
+  socks5_client_userpass_auth_t *val = trunnel_calloc(1, sizeof(socks5_client_userpass_auth_t));
+  if (NULL == val)
+    return NULL;
+  val->version = 1;
+  return val;
+}
+
+/** Release all storage held inside 'obj', but do not free 'obj'.
+ */
+static void
+socks5_client_userpass_auth_clear(socks5_client_userpass_auth_t *obj)
+{
+  (void) obj;
+  TRUNNEL_DYNARRAY_WIPE(&obj->username);
+  TRUNNEL_DYNARRAY_CLEAR(&obj->username);
+  TRUNNEL_DYNARRAY_WIPE(&obj->passwd);
+  TRUNNEL_DYNARRAY_CLEAR(&obj->passwd);
+}
+
+void
+socks5_client_userpass_auth_free(socks5_client_userpass_auth_t *obj)
+{
+  if (obj == NULL)
+    return;
+  socks5_client_userpass_auth_clear(obj);
+  trunnel_memwipe(obj, sizeof(socks5_client_userpass_auth_t));
+  trunnel_free_(obj);
+}
+
+uint8_t
+socks5_client_userpass_auth_get_version(const socks5_client_userpass_auth_t *inp)
+{
+  return inp->version;
+}
+int
+socks5_client_userpass_auth_set_version(socks5_client_userpass_auth_t *inp, uint8_t val)
+{
+  if (! ((val == 1))) {
+     TRUNNEL_SET_ERROR_CODE(inp);
+     return -1;
+  }
+  inp->version = val;
+  return 0;
+}
+uint8_t
+socks5_client_userpass_auth_get_username_len(const socks5_client_userpass_auth_t *inp)
+{
+  return inp->username_len;
+}
+int
+socks5_client_userpass_auth_set_username_len(socks5_client_userpass_auth_t *inp, uint8_t val)
+{
+  inp->username_len = val;
+  return 0;
+}
+size_t
+socks5_client_userpass_auth_getlen_username(const socks5_client_userpass_auth_t *inp)
+{
+  return TRUNNEL_DYNARRAY_LEN(&inp->username);
+}
+
+char
+socks5_client_userpass_auth_get_username(socks5_client_userpass_auth_t *inp, size_t idx)
+{
+  return TRUNNEL_DYNARRAY_GET(&inp->username, idx);
+}
+
+char
+socks5_client_userpass_auth_getconst_username(const socks5_client_userpass_auth_t *inp, size_t idx)
+{
+  return socks5_client_userpass_auth_get_username((socks5_client_userpass_auth_t*)inp, idx);
+}
+int
+socks5_client_userpass_auth_set_username(socks5_client_userpass_auth_t *inp, size_t idx, char elt)
+{
+  TRUNNEL_DYNARRAY_SET(&inp->username, idx, elt);
+  return 0;
+}
+int
+socks5_client_userpass_auth_add_username(socks5_client_userpass_auth_t *inp, char elt)
+{
+#if SIZE_MAX >= UINT8_MAX
+  if (inp->username.n_ == UINT8_MAX)
+    goto trunnel_alloc_failed;
+#endif
+  TRUNNEL_DYNARRAY_ADD(char, &inp->username, elt, {});
+  return 0;
+ trunnel_alloc_failed:
+  TRUNNEL_SET_ERROR_CODE(inp);
+  return -1;
+}
+
+char *
+socks5_client_userpass_auth_getarray_username(socks5_client_userpass_auth_t *inp)
+{
+  return inp->username.elts_;
+}
+const char  *
+socks5_client_userpass_auth_getconstarray_username(const socks5_client_userpass_auth_t *inp)
+{
+  return (const char  *)socks5_client_userpass_auth_getarray_username((socks5_client_userpass_auth_t*)inp);
+}
+int
+socks5_client_userpass_auth_setlen_username(socks5_client_userpass_auth_t *inp, size_t newlen)
+{
+#if UINT8_MAX < SIZE_MAX
+  if (newlen > UINT8_MAX)
+    goto trunnel_alloc_failed;
+#endif
+  return trunnel_string_setlen(&inp->username, newlen,
+            &inp->trunnel_error_code_);
+ trunnel_alloc_failed:
+  TRUNNEL_SET_ERROR_CODE(inp);
+  return -1;
+}
+const char *
+socks5_client_userpass_auth_getstr_username(socks5_client_userpass_auth_t *inp)
+{
+  return trunnel_string_getstr(&inp->username);
+}
+int
+socks5_client_userpass_auth_setstr0_username(socks5_client_userpass_auth_t *inp, const char *val, size_t len)
+{
+#if UINT8_MAX < SIZE_MAX
+  if (len > UINT8_MAX) {
+    TRUNNEL_SET_ERROR_CODE(inp);
+    return -1;
+  }
+#endif
+  return trunnel_string_setstr0(&inp->username, val, len, &inp->trunnel_error_code_);
+}
+int
+socks5_client_userpass_auth_setstr_username(socks5_client_userpass_auth_t *inp, const char *val)
+{
+  return socks5_client_userpass_auth_setstr0_username(inp, val, strlen(val));
+}
+uint8_t
+socks5_client_userpass_auth_get_passwd_len(const socks5_client_userpass_auth_t *inp)
+{
+  return inp->passwd_len;
+}
+int
+socks5_client_userpass_auth_set_passwd_len(socks5_client_userpass_auth_t *inp, uint8_t val)
+{
+  inp->passwd_len = val;
+  return 0;
+}
+size_t
+socks5_client_userpass_auth_getlen_passwd(const socks5_client_userpass_auth_t *inp)
+{
+  return TRUNNEL_DYNARRAY_LEN(&inp->passwd);
+}
+
+char
+socks5_client_userpass_auth_get_passwd(socks5_client_userpass_auth_t *inp, size_t idx)
+{
+  return TRUNNEL_DYNARRAY_GET(&inp->passwd, idx);
+}
+
+char
+socks5_client_userpass_auth_getconst_passwd(const socks5_client_userpass_auth_t *inp, size_t idx)
+{
+  return socks5_client_userpass_auth_get_passwd((socks5_client_userpass_auth_t*)inp, idx);
+}
+int
+socks5_client_userpass_auth_set_passwd(socks5_client_userpass_auth_t *inp, size_t idx, char elt)
+{
+  TRUNNEL_DYNARRAY_SET(&inp->passwd, idx, elt);
+  return 0;
+}
+int
+socks5_client_userpass_auth_add_passwd(socks5_client_userpass_auth_t *inp, char elt)
+{
+#if SIZE_MAX >= UINT8_MAX
+  if (inp->passwd.n_ == UINT8_MAX)
+    goto trunnel_alloc_failed;
+#endif
+  TRUNNEL_DYNARRAY_ADD(char, &inp->passwd, elt, {});
+  return 0;
+ trunnel_alloc_failed:
+  TRUNNEL_SET_ERROR_CODE(inp);
+  return -1;
+}
+
+char *
+socks5_client_userpass_auth_getarray_passwd(socks5_client_userpass_auth_t *inp)
+{
+  return inp->passwd.elts_;
+}
+const char  *
+socks5_client_userpass_auth_getconstarray_passwd(const socks5_client_userpass_auth_t *inp)
+{
+  return (const char  *)socks5_client_userpass_auth_getarray_passwd((socks5_client_userpass_auth_t*)inp);
+}
+int
+socks5_client_userpass_auth_setlen_passwd(socks5_client_userpass_auth_t *inp, size_t newlen)
+{
+#if UINT8_MAX < SIZE_MAX
+  if (newlen > UINT8_MAX)
+    goto trunnel_alloc_failed;
+#endif
+  return trunnel_string_setlen(&inp->passwd, newlen,
+            &inp->trunnel_error_code_);
+ trunnel_alloc_failed:
+  TRUNNEL_SET_ERROR_CODE(inp);
+  return -1;
+}
+const char *
+socks5_client_userpass_auth_getstr_passwd(socks5_client_userpass_auth_t *inp)
+{
+  return trunnel_string_getstr(&inp->passwd);
+}
+int
+socks5_client_userpass_auth_setstr0_passwd(socks5_client_userpass_auth_t *inp, const char *val, size_t len)
+{
+#if UINT8_MAX < SIZE_MAX
+  if (len > UINT8_MAX) {
+    TRUNNEL_SET_ERROR_CODE(inp);
+    return -1;
+  }
+#endif
+  return trunnel_string_setstr0(&inp->passwd, val, len, &inp->trunnel_error_code_);
+}
+int
+socks5_client_userpass_auth_setstr_passwd(socks5_client_userpass_auth_t *inp, const char *val)
+{
+  return socks5_client_userpass_auth_setstr0_passwd(inp, val, strlen(val));
+}
+const char *
+socks5_client_userpass_auth_check(const socks5_client_userpass_auth_t *obj)
+{
+  if (obj == NULL)
+    return "Object was NULL";
+  if (obj->trunnel_error_code_)
+    return "A set function failed on this object";
+  if (! (obj->version == 1))
+    return "Integer out of bounds";
+  if (TRUNNEL_DYNARRAY_LEN(&obj->username) != obj->username_len)
+    return "Length mismatch for username";
+  if (TRUNNEL_DYNARRAY_LEN(&obj->passwd) != obj->passwd_len)
+    return "Length mismatch for passwd";
+  return NULL;
+}
+
+ssize_t
+socks5_client_userpass_auth_encoded_len(const socks5_client_userpass_auth_t *obj)
+{
+  ssize_t result = 0;
+
+  if (NULL != socks5_client_userpass_auth_check(obj))
+     return -1;
+
+
+  /* Length of u8 version IN [1] */
+  result += 1;
+
+  /* Length of u8 username_len */
+  result += 1;
+
+  /* Length of char username[username_len] */
+  result += TRUNNEL_DYNARRAY_LEN(&obj->username);
+
+  /* Length of u8 passwd_len */
+  result += 1;
+
+  /* Length of char passwd[passwd_len] */
+  result += TRUNNEL_DYNARRAY_LEN(&obj->passwd);
+  return result;
+}
+int
+socks5_client_userpass_auth_clear_errors(socks5_client_userpass_auth_t *obj)
+{
+  int r = obj->trunnel_error_code_;
+  obj->trunnel_error_code_ = 0;
+  return r;
+}
+ssize_t
+socks5_client_userpass_auth_encode(uint8_t *output, const size_t avail, const socks5_client_userpass_auth_t *obj)
+{
+  ssize_t result = 0;
+  size_t written = 0;
+  uint8_t *ptr = output;
+  const char *msg;
+#ifdef TRUNNEL_CHECK_ENCODED_LEN
+  const ssize_t encoded_len = socks5_client_userpass_auth_encoded_len(obj);
+#endif
+
+  if (NULL != (msg = socks5_client_userpass_auth_check(obj)))
+    goto check_failed;
+
+#ifdef TRUNNEL_CHECK_ENCODED_LEN
+  trunnel_assert(encoded_len >= 0);
+#endif
+
+  /* Encode u8 version IN [1] */
+  trunnel_assert(written <= avail);
+  if (avail - written < 1)
+    goto truncated;
+  trunnel_set_uint8(ptr, (obj->version));
+  written += 1; ptr += 1;
+
+  /* Encode u8 username_len */
+  trunnel_assert(written <= avail);
+  if (avail - written < 1)
+    goto truncated;
+  trunnel_set_uint8(ptr, (obj->username_len));
+  written += 1; ptr += 1;
+
+  /* Encode char username[username_len] */
+  {
+    size_t elt_len = TRUNNEL_DYNARRAY_LEN(&obj->username);
+    trunnel_assert(obj->username_len == elt_len);
+    trunnel_assert(written <= avail);
+    if (avail - written < elt_len)
+      goto truncated;
+    if (elt_len)
+      memcpy(ptr, obj->username.elts_, elt_len);
+    written += elt_len; ptr += elt_len;
+  }
+
+  /* Encode u8 passwd_len */
+  trunnel_assert(written <= avail);
+  if (avail - written < 1)
+    goto truncated;
+  trunnel_set_uint8(ptr, (obj->passwd_len));
+  written += 1; ptr += 1;
+
+  /* Encode char passwd[passwd_len] */
+  {
+    size_t elt_len = TRUNNEL_DYNARRAY_LEN(&obj->passwd);
+    trunnel_assert(obj->passwd_len == elt_len);
+    trunnel_assert(written <= avail);
+    if (avail - written < elt_len)
+      goto truncated;
+    if (elt_len)
+      memcpy(ptr, obj->passwd.elts_, elt_len);
+    written += elt_len; ptr += elt_len;
+  }
+
+
+  trunnel_assert(ptr == output + written);
+#ifdef TRUNNEL_CHECK_ENCODED_LEN
+  {
+    trunnel_assert(encoded_len >= 0);
+    trunnel_assert((size_t)encoded_len == written);
+  }
+
+#endif
+
+  return written;
+
+ truncated:
+  result = -2;
+  goto fail;
+ check_failed:
+  (void)msg;
+  result = -1;
+  goto fail;
+ fail:
+  trunnel_assert(result < 0);
+  return result;
+}
+
+/** As socks5_client_userpass_auth_parse(), but do not allocate the
+ * output object.
+ */
+static ssize_t
+socks5_client_userpass_auth_parse_into(socks5_client_userpass_auth_t *obj, const uint8_t *input, const size_t len_in)
+{
+  const uint8_t *ptr = input;
+  size_t remaining = len_in;
+  ssize_t result = 0;
+  (void)result;
+
+  /* Parse u8 version IN [1] */
+  CHECK_REMAINING(1, truncated);
+  obj->version = (trunnel_get_uint8(ptr));
+  remaining -= 1; ptr += 1;
+  if (! (obj->version == 1))
+    goto fail;
+
+  /* Parse u8 username_len */
+  CHECK_REMAINING(1, truncated);
+  obj->username_len = (trunnel_get_uint8(ptr));
+  remaining -= 1; ptr += 1;
+
+  /* Parse char username[username_len] */
+  CHECK_REMAINING(obj->username_len, truncated);
+  if (socks5_client_userpass_auth_setstr0_username(obj, (const char*)ptr, obj->username_len))
+    goto fail;
+  ptr += obj->username_len; remaining -= obj->username_len;
+
+  /* Parse u8 passwd_len */
+  CHECK_REMAINING(1, truncated);
+  obj->passwd_len = (trunnel_get_uint8(ptr));
+  remaining -= 1; ptr += 1;
+
+  /* Parse char passwd[passwd_len] */
+  CHECK_REMAINING(obj->passwd_len, truncated);
+  if (socks5_client_userpass_auth_setstr0_passwd(obj, (const char*)ptr, obj->passwd_len))
+    goto fail;
+  ptr += obj->passwd_len; remaining -= obj->passwd_len;
+  trunnel_assert(ptr + remaining == input + len_in);
+  return len_in - remaining;
+
+ truncated:
+  return -2;
+ fail:
+  result = -1;
+  return result;
+}
+
+ssize_t
+socks5_client_userpass_auth_parse(socks5_client_userpass_auth_t **output, const uint8_t *input, const size_t len_in)
+{
+  ssize_t result;
+  *output = socks5_client_userpass_auth_new();
+  if (NULL == *output)
+    return -1;
+  result = socks5_client_userpass_auth_parse_into(*output, input, len_in);
+  if (result < 0) {
+    socks5_client_userpass_auth_free(*output);
+    *output = NULL;
+  }
+  return result;
+}
+socks5_client_version_t *
+socks5_client_version_new(void)
+{
+  socks5_client_version_t *val = trunnel_calloc(1, sizeof(socks5_client_version_t));
+  if (NULL == val)
+    return NULL;
+  val->version = 5;
+  return val;
+}
+
+/** Release all storage held inside 'obj', but do not free 'obj'.
+ */
+static void
+socks5_client_version_clear(socks5_client_version_t *obj)
+{
+  (void) obj;
+  TRUNNEL_DYNARRAY_WIPE(&obj->methods);
+  TRUNNEL_DYNARRAY_CLEAR(&obj->methods);
+}
+
+void
+socks5_client_version_free(socks5_client_version_t *obj)
+{
+  if (obj == NULL)
+    return;
+  socks5_client_version_clear(obj);
+  trunnel_memwipe(obj, sizeof(socks5_client_version_t));
+  trunnel_free_(obj);
+}
+
+uint8_t
+socks5_client_version_get_version(const socks5_client_version_t *inp)
+{
+  return inp->version;
+}
+int
+socks5_client_version_set_version(socks5_client_version_t *inp, uint8_t val)
+{
+  if (! ((val == 5))) {
+     TRUNNEL_SET_ERROR_CODE(inp);
+     return -1;
+  }
+  inp->version = val;
+  return 0;
+}
+uint8_t
+socks5_client_version_get_n_methods(const socks5_client_version_t *inp)
+{
+  return inp->n_methods;
+}
+int
+socks5_client_version_set_n_methods(socks5_client_version_t *inp, uint8_t val)
+{
+  inp->n_methods = val;
+  return 0;
+}
+size_t
+socks5_client_version_getlen_methods(const socks5_client_version_t *inp)
+{
+  return TRUNNEL_DYNARRAY_LEN(&inp->methods);
+}
+
+uint8_t
+socks5_client_version_get_methods(socks5_client_version_t *inp, size_t idx)
+{
+  return TRUNNEL_DYNARRAY_GET(&inp->methods, idx);
+}
+
+uint8_t
+socks5_client_version_getconst_methods(const socks5_client_version_t *inp, size_t idx)
+{
+  return socks5_client_version_get_methods((socks5_client_version_t*)inp, idx);
+}
+int
+socks5_client_version_set_methods(socks5_client_version_t *inp, size_t idx, uint8_t elt)
+{
+  TRUNNEL_DYNARRAY_SET(&inp->methods, idx, elt);
+  return 0;
+}
+int
+socks5_client_version_add_methods(socks5_client_version_t *inp, uint8_t elt)
+{
+#if SIZE_MAX >= UINT8_MAX
+  if (inp->methods.n_ == UINT8_MAX)
+    goto trunnel_alloc_failed;
+#endif
+  TRUNNEL_DYNARRAY_ADD(uint8_t, &inp->methods, elt, {});
+  return 0;
+ trunnel_alloc_failed:
+  TRUNNEL_SET_ERROR_CODE(inp);
+  return -1;
+}
+
+uint8_t *
+socks5_client_version_getarray_methods(socks5_client_version_t *inp)
+{
+  return inp->methods.elts_;
+}
+const uint8_t  *
+socks5_client_version_getconstarray_methods(const socks5_client_version_t *inp)
+{
+  return (const uint8_t  *)socks5_client_version_getarray_methods((socks5_client_version_t*)inp);
+}
+int
+socks5_client_version_setlen_methods(socks5_client_version_t *inp, size_t newlen)
+{
+  uint8_t *newptr;
+#if UINT8_MAX < SIZE_MAX
+  if (newlen > UINT8_MAX)
+    goto trunnel_alloc_failed;
+#endif
+  newptr = trunnel_dynarray_setlen(&inp->methods.allocated_,
+                 &inp->methods.n_, inp->methods.elts_, newlen,
+                 sizeof(inp->methods.elts_[0]), (trunnel_free_fn_t) NULL,
+                 &inp->trunnel_error_code_);
+  if (newlen != 0 && newptr == NULL)
+    goto trunnel_alloc_failed;
+  inp->methods.elts_ = newptr;
+  return 0;
+ trunnel_alloc_failed:
+  TRUNNEL_SET_ERROR_CODE(inp);
+  return -1;
+}
+const char *
+socks5_client_version_check(const socks5_client_version_t *obj)
+{
+  if (obj == NULL)
+    return "Object was NULL";
+  if (obj->trunnel_error_code_)
+    return "A set function failed on this object";
+  if (! (obj->version == 5))
+    return "Integer out of bounds";
+  if (TRUNNEL_DYNARRAY_LEN(&obj->methods) != obj->n_methods)
+    return "Length mismatch for methods";
+  return NULL;
+}
+
+ssize_t
+socks5_client_version_encoded_len(const socks5_client_version_t *obj)
+{
+  ssize_t result = 0;
+
+  if (NULL != socks5_client_version_check(obj))
+     return -1;
+
+
+  /* Length of u8 version IN [5] */
+  result += 1;
+
+  /* Length of u8 n_methods */
+  result += 1;
+
+  /* Length of u8 methods[n_methods] */
+  result += TRUNNEL_DYNARRAY_LEN(&obj->methods);
+  return result;
+}
+int
+socks5_client_version_clear_errors(socks5_client_version_t *obj)
+{
+  int r = obj->trunnel_error_code_;
+  obj->trunnel_error_code_ = 0;
+  return r;
+}
+ssize_t
+socks5_client_version_encode(uint8_t *output, const size_t avail, const socks5_client_version_t *obj)
+{
+  ssize_t result = 0;
+  size_t written = 0;
+  uint8_t *ptr = output;
+  const char *msg;
+#ifdef TRUNNEL_CHECK_ENCODED_LEN
+  const ssize_t encoded_len = socks5_client_version_encoded_len(obj);
+#endif
+
+  if (NULL != (msg = socks5_client_version_check(obj)))
+    goto check_failed;
+
+#ifdef TRUNNEL_CHECK_ENCODED_LEN
+  trunnel_assert(encoded_len >= 0);
+#endif
+
+  /* Encode u8 version IN [5] */
+  trunnel_assert(written <= avail);
+  if (avail - written < 1)
+    goto truncated;
+  trunnel_set_uint8(ptr, (obj->version));
+  written += 1; ptr += 1;
+
+  /* Encode u8 n_methods */
+  trunnel_assert(written <= avail);
+  if (avail - written < 1)
+    goto truncated;
+  trunnel_set_uint8(ptr, (obj->n_methods));
+  written += 1; ptr += 1;
+
+  /* Encode u8 methods[n_methods] */
+  {
+    size_t elt_len = TRUNNEL_DYNARRAY_LEN(&obj->methods);
+    trunnel_assert(obj->n_methods == elt_len);
+    trunnel_assert(written <= avail);
+    if (avail - written < elt_len)
+      goto truncated;
+    if (elt_len)
+      memcpy(ptr, obj->methods.elts_, elt_len);
+    written += elt_len; ptr += elt_len;
+  }
+
+
+  trunnel_assert(ptr == output + written);
+#ifdef TRUNNEL_CHECK_ENCODED_LEN
+  {
+    trunnel_assert(encoded_len >= 0);
+    trunnel_assert((size_t)encoded_len == written);
+  }
+
+#endif
+
+  return written;
+
+ truncated:
+  result = -2;
+  goto fail;
+ check_failed:
+  (void)msg;
+  result = -1;
+  goto fail;
+ fail:
+  trunnel_assert(result < 0);
+  return result;
+}
+
+/** As socks5_client_version_parse(), but do not allocate the output
+ * object.
+ */
+static ssize_t
+socks5_client_version_parse_into(socks5_client_version_t *obj, const uint8_t *input, const size_t len_in)
+{
+  const uint8_t *ptr = input;
+  size_t remaining = len_in;
+  ssize_t result = 0;
+  (void)result;
+
+  /* Parse u8 version IN [5] */
+  CHECK_REMAINING(1, truncated);
+  obj->version = (trunnel_get_uint8(ptr));
+  remaining -= 1; ptr += 1;
+  if (! (obj->version == 5))
+    goto fail;
+
+  /* Parse u8 n_methods */
+  CHECK_REMAINING(1, truncated);
+  obj->n_methods = (trunnel_get_uint8(ptr));
+  remaining -= 1; ptr += 1;
+
+  /* Parse u8 methods[n_methods] */
+  CHECK_REMAINING(obj->n_methods, truncated);
+  TRUNNEL_DYNARRAY_EXPAND(uint8_t, &obj->methods, obj->n_methods, {});
+  obj->methods.n_ = obj->n_methods;
+  if (obj->n_methods)
+    memcpy(obj->methods.elts_, ptr, obj->n_methods);
+  ptr += obj->n_methods; remaining -= obj->n_methods;
+  trunnel_assert(ptr + remaining == input + len_in);
+  return len_in - remaining;
+
+ truncated:
+  return -2;
+ trunnel_alloc_failed:
+  return -1;
+ fail:
+  result = -1;
+  return result;
+}
+
+ssize_t
+socks5_client_version_parse(socks5_client_version_t **output, const uint8_t *input, const size_t len_in)
+{
+  ssize_t result;
+  *output = socks5_client_version_new();
+  if (NULL == *output)
+    return -1;
+  result = socks5_client_version_parse_into(*output, input, len_in);
+  if (result < 0) {
+    socks5_client_version_free(*output);
+    *output = NULL;
+  }
+  return result;
+}
+socks5_server_method_t *
+socks5_server_method_new(void)
+{
+  socks5_server_method_t *val = trunnel_calloc(1, sizeof(socks5_server_method_t));
+  if (NULL == val)
+    return NULL;
+  val->version = 5;
+  return val;
+}
+
+/** Release all storage held inside 'obj', but do not free 'obj'.
+ */
+static void
+socks5_server_method_clear(socks5_server_method_t *obj)
+{
+  (void) obj;
+}
+
+void
+socks5_server_method_free(socks5_server_method_t *obj)
+{
+  if (obj == NULL)
+    return;
+  socks5_server_method_clear(obj);
+  trunnel_memwipe(obj, sizeof(socks5_server_method_t));
+  trunnel_free_(obj);
+}
+
+uint8_t
+socks5_server_method_get_version(const socks5_server_method_t *inp)
+{
+  return inp->version;
+}
+int
+socks5_server_method_set_version(socks5_server_method_t *inp, uint8_t val)
+{
+  if (! ((val == 5))) {
+     TRUNNEL_SET_ERROR_CODE(inp);
+     return -1;
+  }
+  inp->version = val;
+  return 0;
+}
+uint8_t
+socks5_server_method_get_method(const socks5_server_method_t *inp)
+{
+  return inp->method;
+}
+int
+socks5_server_method_set_method(socks5_server_method_t *inp, uint8_t val)
+{
+  inp->method = val;
+  return 0;
+}
+const char *
+socks5_server_method_check(const socks5_server_method_t *obj)
+{
+  if (obj == NULL)
+    return "Object was NULL";
+  if (obj->trunnel_error_code_)
+    return "A set function failed on this object";
+  if (! (obj->version == 5))
+    return "Integer out of bounds";
+  return NULL;
+}
+
+ssize_t
+socks5_server_method_encoded_len(const socks5_server_method_t *obj)
+{
+  ssize_t result = 0;
+
+  if (NULL != socks5_server_method_check(obj))
+     return -1;
+
+
+  /* Length of u8 version IN [5] */
+  result += 1;
+
+  /* Length of u8 method */
+  result += 1;
+  return result;
+}
+int
+socks5_server_method_clear_errors(socks5_server_method_t *obj)
+{
+  int r = obj->trunnel_error_code_;
+  obj->trunnel_error_code_ = 0;
+  return r;
+}
+ssize_t
+socks5_server_method_encode(uint8_t *output, const size_t avail, const socks5_server_method_t *obj)
+{
+  ssize_t result = 0;
+  size_t written = 0;
+  uint8_t *ptr = output;
+  const char *msg;
+#ifdef TRUNNEL_CHECK_ENCODED_LEN
+  const ssize_t encoded_len = socks5_server_method_encoded_len(obj);
+#endif
+
+  if (NULL != (msg = socks5_server_method_check(obj)))
+    goto check_failed;
+
+#ifdef TRUNNEL_CHECK_ENCODED_LEN
+  trunnel_assert(encoded_len >= 0);
+#endif
+
+  /* Encode u8 version IN [5] */
+  trunnel_assert(written <= avail);
+  if (avail - written < 1)
+    goto truncated;
+  trunnel_set_uint8(ptr, (obj->version));
+  written += 1; ptr += 1;
+
+  /* Encode u8 method */
+  trunnel_assert(written <= avail);
+  if (avail - written < 1)
+    goto truncated;
+  trunnel_set_uint8(ptr, (obj->method));
+  written += 1; ptr += 1;
+
+
+  trunnel_assert(ptr == output + written);
+#ifdef TRUNNEL_CHECK_ENCODED_LEN
+  {
+    trunnel_assert(encoded_len >= 0);
+    trunnel_assert((size_t)encoded_len == written);
+  }
+
+#endif
+
+  return written;
+
+ truncated:
+  result = -2;
+  goto fail;
+ check_failed:
+  (void)msg;
+  result = -1;
+  goto fail;
+ fail:
+  trunnel_assert(result < 0);
+  return result;
+}
+
+/** As socks5_server_method_parse(), but do not allocate the output
+ * object.
+ */
+static ssize_t
+socks5_server_method_parse_into(socks5_server_method_t *obj, const uint8_t *input, const size_t len_in)
+{
+  const uint8_t *ptr = input;
+  size_t remaining = len_in;
+  ssize_t result = 0;
+  (void)result;
+
+  /* Parse u8 version IN [5] */
+  CHECK_REMAINING(1, truncated);
+  obj->version = (trunnel_get_uint8(ptr));
+  remaining -= 1; ptr += 1;
+  if (! (obj->version == 5))
+    goto fail;
+
+  /* Parse u8 method */
+  CHECK_REMAINING(1, truncated);
+  obj->method = (trunnel_get_uint8(ptr));
+  remaining -= 1; ptr += 1;
+  trunnel_assert(ptr + remaining == input + len_in);
+  return len_in - remaining;
+
+ truncated:
+  return -2;
+ fail:
+  result = -1;
+  return result;
+}
+
+ssize_t
+socks5_server_method_parse(socks5_server_method_t **output, const uint8_t *input, const size_t len_in)
+{
+  ssize_t result;
+  *output = socks5_server_method_new();
+  if (NULL == *output)
+    return -1;
+  result = socks5_server_method_parse_into(*output, input, len_in);
+  if (result < 0) {
+    socks5_server_method_free(*output);
+    *output = NULL;
+  }
+  return result;
+}
+socks5_server_userpass_auth_t *
+socks5_server_userpass_auth_new(void)
+{
+  socks5_server_userpass_auth_t *val = trunnel_calloc(1, sizeof(socks5_server_userpass_auth_t));
+  if (NULL == val)
+    return NULL;
+  val->version = 1;
+  return val;
+}
+
+/** Release all storage held inside 'obj', but do not free 'obj'.
+ */
+static void
+socks5_server_userpass_auth_clear(socks5_server_userpass_auth_t *obj)
+{
+  (void) obj;
+}
+
+void
+socks5_server_userpass_auth_free(socks5_server_userpass_auth_t *obj)
+{
+  if (obj == NULL)
+    return;
+  socks5_server_userpass_auth_clear(obj);
+  trunnel_memwipe(obj, sizeof(socks5_server_userpass_auth_t));
+  trunnel_free_(obj);
+}
+
+uint8_t
+socks5_server_userpass_auth_get_version(const socks5_server_userpass_auth_t *inp)
+{
+  return inp->version;
+}
+int
+socks5_server_userpass_auth_set_version(socks5_server_userpass_auth_t *inp, uint8_t val)
+{
+  if (! ((val == 1))) {
+     TRUNNEL_SET_ERROR_CODE(inp);
+     return -1;
+  }
+  inp->version = val;
+  return 0;
+}
+uint8_t
+socks5_server_userpass_auth_get_status(const socks5_server_userpass_auth_t *inp)
+{
+  return inp->status;
+}
+int
+socks5_server_userpass_auth_set_status(socks5_server_userpass_auth_t *inp, uint8_t val)
+{
+  inp->status = val;
+  return 0;
+}
+const char *
+socks5_server_userpass_auth_check(const socks5_server_userpass_auth_t *obj)
+{
+  if (obj == NULL)
+    return "Object was NULL";
+  if (obj->trunnel_error_code_)
+    return "A set function failed on this object";
+  if (! (obj->version == 1))
+    return "Integer out of bounds";
+  return NULL;
+}
+
+ssize_t
+socks5_server_userpass_auth_encoded_len(const socks5_server_userpass_auth_t *obj)
+{
+  ssize_t result = 0;
+
+  if (NULL != socks5_server_userpass_auth_check(obj))
+     return -1;
+
+
+  /* Length of u8 version IN [1] */
+  result += 1;
+
+  /* Length of u8 status */
+  result += 1;
+  return result;
+}
+int
+socks5_server_userpass_auth_clear_errors(socks5_server_userpass_auth_t *obj)
+{
+  int r = obj->trunnel_error_code_;
+  obj->trunnel_error_code_ = 0;
+  return r;
+}
+ssize_t
+socks5_server_userpass_auth_encode(uint8_t *output, const size_t avail, const socks5_server_userpass_auth_t *obj)
+{
+  ssize_t result = 0;
+  size_t written = 0;
+  uint8_t *ptr = output;
+  const char *msg;
+#ifdef TRUNNEL_CHECK_ENCODED_LEN
+  const ssize_t encoded_len = socks5_server_userpass_auth_encoded_len(obj);
+#endif
+
+  if (NULL != (msg = socks5_server_userpass_auth_check(obj)))
+    goto check_failed;
+
+#ifdef TRUNNEL_CHECK_ENCODED_LEN
+  trunnel_assert(encoded_len >= 0);
+#endif
+
+  /* Encode u8 version IN [1] */
+  trunnel_assert(written <= avail);
+  if (avail - written < 1)
+    goto truncated;
+  trunnel_set_uint8(ptr, (obj->version));
+  written += 1; ptr += 1;
+
+  /* Encode u8 status */
+  trunnel_assert(written <= avail);
+  if (avail - written < 1)
+    goto truncated;
+  trunnel_set_uint8(ptr, (obj->status));
+  written += 1; ptr += 1;
+
+
+  trunnel_assert(ptr == output + written);
+#ifdef TRUNNEL_CHECK_ENCODED_LEN
+  {
+    trunnel_assert(encoded_len >= 0);
+    trunnel_assert((size_t)encoded_len == written);
+  }
+
+#endif
+
+  return written;
+
+ truncated:
+  result = -2;
+  goto fail;
+ check_failed:
+  (void)msg;
+  result = -1;
+  goto fail;
+ fail:
+  trunnel_assert(result < 0);
+  return result;
+}
+
+/** As socks5_server_userpass_auth_parse(), but do not allocate the
+ * output object.
+ */
+static ssize_t
+socks5_server_userpass_auth_parse_into(socks5_server_userpass_auth_t *obj, const uint8_t *input, const size_t len_in)
+{
+  const uint8_t *ptr = input;
+  size_t remaining = len_in;
+  ssize_t result = 0;
+  (void)result;
+
+  /* Parse u8 version IN [1] */
+  CHECK_REMAINING(1, truncated);
+  obj->version = (trunnel_get_uint8(ptr));
+  remaining -= 1; ptr += 1;
+  if (! (obj->version == 1))
+    goto fail;
+
+  /* Parse u8 status */
+  CHECK_REMAINING(1, truncated);
+  obj->status = (trunnel_get_uint8(ptr));
+  remaining -= 1; ptr += 1;
+  trunnel_assert(ptr + remaining == input + len_in);
+  return len_in - remaining;
+
+ truncated:
+  return -2;
+ fail:
+  result = -1;
+  return result;
+}
+
+ssize_t
+socks5_server_userpass_auth_parse(socks5_server_userpass_auth_t **output, const uint8_t *input, const size_t len_in)
+{
+  ssize_t result;
+  *output = socks5_server_userpass_auth_new();
+  if (NULL == *output)
+    return -1;
+  result = socks5_server_userpass_auth_parse_into(*output, input, len_in);
+  if (result < 0) {
+    socks5_server_userpass_auth_free(*output);
+    *output = NULL;
+  }
+  return result;
+}
+socks5_client_request_t *
+socks5_client_request_new(void)
+{
+  socks5_client_request_t *val = trunnel_calloc(1, sizeof(socks5_client_request_t));
+  if (NULL == val)
+    return NULL;
+  val->version = 5;
+  val->command = CMD_BIND;
+  return val;
+}
+
+/** Release all storage held inside 'obj', but do not free 'obj'.
+ */
+static void
+socks5_client_request_clear(socks5_client_request_t *obj)
+{
+  (void) obj;
+  domainname_free(obj->dest_addr_domainname);
+  obj->dest_addr_domainname = NULL;
+}
+
+void
+socks5_client_request_free(socks5_client_request_t *obj)
+{
+  if (obj == NULL)
+    return;
+  socks5_client_request_clear(obj);
+  trunnel_memwipe(obj, sizeof(socks5_client_request_t));
+  trunnel_free_(obj);
+}
+
+uint8_t
+socks5_client_request_get_version(const socks5_client_request_t *inp)
+{
+  return inp->version;
+}
+int
+socks5_client_request_set_version(socks5_client_request_t *inp, uint8_t val)
+{
+  if (! ((val == 5))) {
+     TRUNNEL_SET_ERROR_CODE(inp);
+     return -1;
+  }
+  inp->version = val;
+  return 0;
+}
+uint8_t
+socks5_client_request_get_command(const socks5_client_request_t *inp)
+{
+  return inp->command;
+}
+int
+socks5_client_request_set_command(socks5_client_request_t *inp, uint8_t val)
+{
+  if (! ((val == CMD_BIND || val == CMD_CONNECT || val == CMD_RESOLVE || val == CMD_RESOLVE_PTR || val == CMD_UDP_ASSOCIATE))) {
+     TRUNNEL_SET_ERROR_CODE(inp);
+     return -1;
+  }
+  inp->command = val;
+  return 0;
+}
+uint8_t
+socks5_client_request_get_reserved(const socks5_client_request_t *inp)
+{
+  return inp->reserved;
+}
+int
+socks5_client_request_set_reserved(socks5_client_request_t *inp, uint8_t val)
+{
+  if (! ((val == 0))) {
+     TRUNNEL_SET_ERROR_CODE(inp);
+     return -1;
+  }
+  inp->reserved = val;
+  return 0;
+}
+uint8_t
+socks5_client_request_get_atype(const socks5_client_request_t *inp)
+{
+  return inp->atype;
+}
+int
+socks5_client_request_set_atype(socks5_client_request_t *inp, uint8_t val)
+{
+  inp->atype = val;
+  return 0;
+}
+uint32_t
+socks5_client_request_get_dest_addr_ipv4(const socks5_client_request_t *inp)
+{
+  return inp->dest_addr_ipv4;
+}
+int
+socks5_client_request_set_dest_addr_ipv4(socks5_client_request_t *inp, uint32_t val)
+{
+  inp->dest_addr_ipv4 = val;
+  return 0;
+}
+size_t
+socks5_client_request_getlen_dest_addr_ipv6(const socks5_client_request_t *inp)
+{
+  (void)inp;  return 16;
+}
+
+uint8_t
+socks5_client_request_get_dest_addr_ipv6(socks5_client_request_t *inp, size_t idx)
+{
+  trunnel_assert(idx < 16);
+  return inp->dest_addr_ipv6[idx];
+}
+
+uint8_t
+socks5_client_request_getconst_dest_addr_ipv6(const socks5_client_request_t *inp, size_t idx)
+{
+  return socks5_client_request_get_dest_addr_ipv6((socks5_client_request_t*)inp, idx);
+}
+int
+socks5_client_request_set_dest_addr_ipv6(socks5_client_request_t *inp, size_t idx, uint8_t elt)
+{
+  trunnel_assert(idx < 16);
+  inp->dest_addr_ipv6[idx] = elt;
+  return 0;
+}
+
+uint8_t *
+socks5_client_request_getarray_dest_addr_ipv6(socks5_client_request_t *inp)
+{
+  return inp->dest_addr_ipv6;
+}
+const uint8_t  *
+socks5_client_request_getconstarray_dest_addr_ipv6(const socks5_client_request_t *inp)
+{
+  return (const uint8_t  *)socks5_client_request_getarray_dest_addr_ipv6((socks5_client_request_t*)inp);
+}
+struct domainname_st *
+socks5_client_request_get_dest_addr_domainname(socks5_client_request_t *inp)
+{
+  return inp->dest_addr_domainname;
+}
+const struct domainname_st *
+socks5_client_request_getconst_dest_addr_domainname(const socks5_client_request_t *inp)
+{
+  return socks5_client_request_get_dest_addr_domainname((socks5_client_request_t*) inp);
+}
+int
+socks5_client_request_set_dest_addr_domainname(socks5_client_request_t *inp, struct domainname_st *val)
+{
+  if (inp->dest_addr_domainname && inp->dest_addr_domainname != val)
+    domainname_free(inp->dest_addr_domainname);
+  return socks5_client_request_set0_dest_addr_domainname(inp, val);
+}
+int
+socks5_client_request_set0_dest_addr_domainname(socks5_client_request_t *inp, struct domainname_st *val)
+{
+  inp->dest_addr_domainname = val;
+  return 0;
+}
+uint16_t
+socks5_client_request_get_dest_port(const socks5_client_request_t *inp)
+{
+  return inp->dest_port;
+}
+int
+socks5_client_request_set_dest_port(socks5_client_request_t *inp, uint16_t val)
+{
+  inp->dest_port = val;
+  return 0;
+}
+const char *
+socks5_client_request_check(const socks5_client_request_t *obj)
+{
+  if (obj == NULL)
+    return "Object was NULL";
+  if (obj->trunnel_error_code_)
+    return "A set function failed on this object";
+  if (! (obj->version == 5))
+    return "Integer out of bounds";
+  if (! (obj->command == CMD_BIND || obj->command == CMD_CONNECT || obj->command == CMD_RESOLVE || obj->command == CMD_RESOLVE_PTR || obj->command == CMD_UDP_ASSOCIATE))
+    return "Integer out of bounds";
+  if (! (obj->reserved == 0))
+    return "Integer out of bounds";
+  switch (obj->atype) {
+
+    case ATYPE_IPV4:
+      break;
+
+    case ATYPE_IPV6:
+      break;
+
+    case ATYPE_DOMAINNAME:
+      {
+        const char *msg;
+        if (NULL != (msg = domainname_check(obj->dest_addr_domainname)))
+          return msg;
+      }
+      break;
+
+    default:
+        return "Bad tag for union";
+      break;
+  }
+  return NULL;
+}
+
+ssize_t
+socks5_client_request_encoded_len(const socks5_client_request_t *obj)
+{
+  ssize_t result = 0;
+
+  if (NULL != socks5_client_request_check(obj))
+     return -1;
+
+
+  /* Length of u8 version IN [5] */
+  result += 1;
+
+  /* Length of u8 command IN [CMD_BIND, CMD_CONNECT, CMD_RESOLVE, CMD_RESOLVE_PTR, CMD_UDP_ASSOCIATE] */
+  result += 1;
+
+  /* Length of u8 reserved IN [0] */
+  result += 1;
+
+  /* Length of u8 atype */
+  result += 1;
+  switch (obj->atype) {
+
+    case ATYPE_IPV4:
+
+      /* Length of u32 dest_addr_ipv4 */
+      result += 4;
+      break;
+
+    case ATYPE_IPV6:
+
+      /* Length of u8 dest_addr_ipv6[16] */
+      result += 16;
+      break;
+
+    case ATYPE_DOMAINNAME:
+
+      /* Length of struct domainname dest_addr_domainname */
+      result += domainname_encoded_len(obj->dest_addr_domainname);
+      break;
+
+    default:
+      trunnel_assert(0);
+      break;
+  }
+
+  /* Length of u16 dest_port */
+  result += 2;
+  return result;
+}
+int
+socks5_client_request_clear_errors(socks5_client_request_t *obj)
+{
+  int r = obj->trunnel_error_code_;
+  obj->trunnel_error_code_ = 0;
+  return r;
+}
+ssize_t
+socks5_client_request_encode(uint8_t *output, const size_t avail, const socks5_client_request_t *obj)
+{
+  ssize_t result = 0;
+  size_t written = 0;
+  uint8_t *ptr = output;
+  const char *msg;
+#ifdef TRUNNEL_CHECK_ENCODED_LEN
+  const ssize_t encoded_len = socks5_client_request_encoded_len(obj);
+#endif
+
+  if (NULL != (msg = socks5_client_request_check(obj)))
+    goto check_failed;
+
+#ifdef TRUNNEL_CHECK_ENCODED_LEN
+  trunnel_assert(encoded_len >= 0);
+#endif
+
+  /* Encode u8 version IN [5] */
+  trunnel_assert(written <= avail);
+  if (avail - written < 1)
+    goto truncated;
+  trunnel_set_uint8(ptr, (obj->version));
+  written += 1; ptr += 1;
+
+  /* Encode u8 command IN [CMD_BIND, CMD_CONNECT, CMD_RESOLVE, CMD_RESOLVE_PTR, CMD_UDP_ASSOCIATE] */
+  trunnel_assert(written <= avail);
+  if (avail - written < 1)
+    goto truncated;
+  trunnel_set_uint8(ptr, (obj->command));
+  written += 1; ptr += 1;
+
+  /* Encode u8 reserved IN [0] */
+  trunnel_assert(written <= avail);
+  if (avail - written < 1)
+    goto truncated;
+  trunnel_set_uint8(ptr, (obj->reserved));
+  written += 1; ptr += 1;
+
+  /* Encode u8 atype */
+  trunnel_assert(written <= avail);
+  if (avail - written < 1)
+    goto truncated;
+  trunnel_set_uint8(ptr, (obj->atype));
+  written += 1; ptr += 1;
+
+  /* Encode union dest_addr[atype] */
+  trunnel_assert(written <= avail);
+  switch (obj->atype) {
+
+    case ATYPE_IPV4:
+
+      /* Encode u32 dest_addr_ipv4 */
+      trunnel_assert(written <= avail);
+      if (avail - written < 4)
+        goto truncated;
+      trunnel_set_uint32(ptr, trunnel_htonl(obj->dest_addr_ipv4));
+      written += 4; ptr += 4;
+      break;
+
+    case ATYPE_IPV6:
+
+      /* Encode u8 dest_addr_ipv6[16] */
+      trunnel_assert(written <= avail);
+      if (avail - written < 16)
+        goto truncated;
+      memcpy(ptr, obj->dest_addr_ipv6, 16);
+      written += 16; ptr += 16;
+      break;
+
+    case ATYPE_DOMAINNAME:
+
+      /* Encode struct domainname dest_addr_domainname */
+      trunnel_assert(written <= avail);
+      result = domainname_encode(ptr, avail - written, obj->dest_addr_domainname);
+      if (result < 0)
+        goto fail; /* XXXXXXX !*/
+      written += result; ptr += result;
+      break;
+
+    default:
+      trunnel_assert(0);
+      break;
+  }
+
+  /* Encode u16 dest_port */
+  trunnel_assert(written <= avail);
+  if (avail - written < 2)
+    goto truncated;
+  trunnel_set_uint16(ptr, trunnel_htons(obj->dest_port));
+  written += 2; ptr += 2;
+
+
+  trunnel_assert(ptr == output + written);
+#ifdef TRUNNEL_CHECK_ENCODED_LEN
+  {
+    trunnel_assert(encoded_len >= 0);
+    trunnel_assert((size_t)encoded_len == written);
+  }
+
+#endif
+
+  return written;
+
+ truncated:
+  result = -2;
+  goto fail;
+ check_failed:
+  (void)msg;
+  result = -1;
+  goto fail;
+ fail:
+  trunnel_assert(result < 0);
+  return result;
+}
+
+/** As socks5_client_request_parse(), but do not allocate the output
+ * object.
+ */
+static ssize_t
+socks5_client_request_parse_into(socks5_client_request_t *obj, const uint8_t *input, const size_t len_in)
+{
+  const uint8_t *ptr = input;
+  size_t remaining = len_in;
+  ssize_t result = 0;
+  (void)result;
+
+  /* Parse u8 version IN [5] */
+  CHECK_REMAINING(1, truncated);
+  obj->version = (trunnel_get_uint8(ptr));
+  remaining -= 1; ptr += 1;
+  if (! (obj->version == 5))
+    goto fail;
+
+  /* Parse u8 command IN [CMD_BIND, CMD_CONNECT, CMD_RESOLVE, CMD_RESOLVE_PTR, CMD_UDP_ASSOCIATE] */
+  CHECK_REMAINING(1, truncated);
+  obj->command = (trunnel_get_uint8(ptr));
+  remaining -= 1; ptr += 1;
+  if (! (obj->command == CMD_BIND || obj->command == CMD_CONNECT || obj->command == CMD_RESOLVE || obj->command == CMD_RESOLVE_PTR || obj->command == CMD_UDP_ASSOCIATE))
+    goto fail;
+
+  /* Parse u8 reserved IN [0] */
+  CHECK_REMAINING(1, truncated);
+  obj->reserved = (trunnel_get_uint8(ptr));
+  remaining -= 1; ptr += 1;
+  if (! (obj->reserved == 0))
+    goto fail;
+
+  /* Parse u8 atype */
+  CHECK_REMAINING(1, truncated);
+  obj->atype = (trunnel_get_uint8(ptr));
+  remaining -= 1; ptr += 1;
+
+  /* Parse union dest_addr[atype] */
+  switch (obj->atype) {
+
+    case ATYPE_IPV4:
+
+      /* Parse u32 dest_addr_ipv4 */
+      CHECK_REMAINING(4, truncated);
+      obj->dest_addr_ipv4 = trunnel_ntohl(trunnel_get_uint32(ptr));
+      remaining -= 4; ptr += 4;
+      break;
+
+    case ATYPE_IPV6:
+
+      /* Parse u8 dest_addr_ipv6[16] */
+      CHECK_REMAINING(16, truncated);
+      memcpy(obj->dest_addr_ipv6, ptr, 16);
+      remaining -= 16; ptr += 16;
+      break;
+
+    case ATYPE_DOMAINNAME:
+
+      /* Parse struct domainname dest_addr_domainname */
+      result = domainname_parse(&obj->dest_addr_domainname, ptr, remaining);
+      if (result < 0)
+        goto relay_fail;
+      trunnel_assert((size_t)result <= remaining);
+      remaining -= result; ptr += result;
+      break;
+
+    default:
+      goto fail;
+      break;
+  }
+
+  /* Parse u16 dest_port */
+  CHECK_REMAINING(2, truncated);
+  obj->dest_port = trunnel_ntohs(trunnel_get_uint16(ptr));
+  remaining -= 2; ptr += 2;
+  trunnel_assert(ptr + remaining == input + len_in);
+  return len_in - remaining;
+
+ truncated:
+  return -2;
+ relay_fail:
+  trunnel_assert(result < 0);
+  return result;
+ fail:
+  result = -1;
+  return result;
+}
+
+ssize_t
+socks5_client_request_parse(socks5_client_request_t **output, const uint8_t *input, const size_t len_in)
+{
+  ssize_t result;
+  *output = socks5_client_request_new();
+  if (NULL == *output)
+    return -1;
+  result = socks5_client_request_parse_into(*output, input, len_in);
+  if (result < 0) {
+    socks5_client_request_free(*output);
+    *output = NULL;
+  }
+  return result;
+}
+socks5_server_reply_t *
+socks5_server_reply_new(void)
+{
+  socks5_server_reply_t *val = trunnel_calloc(1, sizeof(socks5_server_reply_t));
+  if (NULL == val)
+    return NULL;
+  val->version = 5;
+  return val;
+}
+
+/** Release all storage held inside 'obj', but do not free 'obj'.
+ */
+static void
+socks5_server_reply_clear(socks5_server_reply_t *obj)
+{
+  (void) obj;
+  domainname_free(obj->bind_addr_domainname);
+  obj->bind_addr_domainname = NULL;
+}
+
+void
+socks5_server_reply_free(socks5_server_reply_t *obj)
+{
+  if (obj == NULL)
+    return;
+  socks5_server_reply_clear(obj);
+  trunnel_memwipe(obj, sizeof(socks5_server_reply_t));
+  trunnel_free_(obj);
+}
+
+uint8_t
+socks5_server_reply_get_version(const socks5_server_reply_t *inp)
+{
+  return inp->version;
+}
+int
+socks5_server_reply_set_version(socks5_server_reply_t *inp, uint8_t val)
+{
+  if (! ((val == 5))) {
+     TRUNNEL_SET_ERROR_CODE(inp);
+     return -1;
+  }
+  inp->version = val;
+  return 0;
+}
+uint8_t
+socks5_server_reply_get_reply(const socks5_server_reply_t *inp)
+{
+  return inp->reply;
+}
+int
+socks5_server_reply_set_reply(socks5_server_reply_t *inp, uint8_t val)
+{
+  inp->reply = val;
+  return 0;
+}
+uint8_t
+socks5_server_reply_get_reserved(const socks5_server_reply_t *inp)
+{
+  return inp->reserved;
+}
+int
+socks5_server_reply_set_reserved(socks5_server_reply_t *inp, uint8_t val)
+{
+  if (! ((val == 0))) {
+     TRUNNEL_SET_ERROR_CODE(inp);
+     return -1;
+  }
+  inp->reserved = val;
+  return 0;
+}
+uint8_t
+socks5_server_reply_get_atype(const socks5_server_reply_t *inp)
+{
+  return inp->atype;
+}
+int
+socks5_server_reply_set_atype(socks5_server_reply_t *inp, uint8_t val)
+{
+  inp->atype = val;
+  return 0;
+}
+uint32_t
+socks5_server_reply_get_bind_addr_ipv4(const socks5_server_reply_t *inp)
+{
+  return inp->bind_addr_ipv4;
+}
+int
+socks5_server_reply_set_bind_addr_ipv4(socks5_server_reply_t *inp, uint32_t val)
+{
+  inp->bind_addr_ipv4 = val;
+  return 0;
+}
+size_t
+socks5_server_reply_getlen_bind_addr_ipv6(const socks5_server_reply_t *inp)
+{
+  (void)inp;  return 16;
+}
+
+uint8_t
+socks5_server_reply_get_bind_addr_ipv6(socks5_server_reply_t *inp, size_t idx)
+{
+  trunnel_assert(idx < 16);
+  return inp->bind_addr_ipv6[idx];
+}
+
+uint8_t
+socks5_server_reply_getconst_bind_addr_ipv6(const socks5_server_reply_t *inp, size_t idx)
+{
+  return socks5_server_reply_get_bind_addr_ipv6((socks5_server_reply_t*)inp, idx);
+}
+int
+socks5_server_reply_set_bind_addr_ipv6(socks5_server_reply_t *inp, size_t idx, uint8_t elt)
+{
+  trunnel_assert(idx < 16);
+  inp->bind_addr_ipv6[idx] = elt;
+  return 0;
+}
+
+uint8_t *
+socks5_server_reply_getarray_bind_addr_ipv6(socks5_server_reply_t *inp)
+{
+  return inp->bind_addr_ipv6;
+}
+const uint8_t  *
+socks5_server_reply_getconstarray_bind_addr_ipv6(const socks5_server_reply_t *inp)
+{
+  return (const uint8_t  *)socks5_server_reply_getarray_bind_addr_ipv6((socks5_server_reply_t*)inp);
+}
+struct domainname_st *
+socks5_server_reply_get_bind_addr_domainname(socks5_server_reply_t *inp)
+{
+  return inp->bind_addr_domainname;
+}
+const struct domainname_st *
+socks5_server_reply_getconst_bind_addr_domainname(const socks5_server_reply_t *inp)
+{
+  return socks5_server_reply_get_bind_addr_domainname((socks5_server_reply_t*) inp);
+}
+int
+socks5_server_reply_set_bind_addr_domainname(socks5_server_reply_t *inp, struct domainname_st *val)
+{
+  if (inp->bind_addr_domainname && inp->bind_addr_domainname != val)
+    domainname_free(inp->bind_addr_domainname);
+  return socks5_server_reply_set0_bind_addr_domainname(inp, val);
+}
+int
+socks5_server_reply_set0_bind_addr_domainname(socks5_server_reply_t *inp, struct domainname_st *val)
+{
+  inp->bind_addr_domainname = val;
+  return 0;
+}
+uint16_t
+socks5_server_reply_get_bind_port(const socks5_server_reply_t *inp)
+{
+  return inp->bind_port;
+}
+int
+socks5_server_reply_set_bind_port(socks5_server_reply_t *inp, uint16_t val)
+{
+  inp->bind_port = val;
+  return 0;
+}
+const char *
+socks5_server_reply_check(const socks5_server_reply_t *obj)
+{
+  if (obj == NULL)
+    return "Object was NULL";
+  if (obj->trunnel_error_code_)
+    return "A set function failed on this object";
+  if (! (obj->version == 5))
+    return "Integer out of bounds";
+  if (! (obj->reserved == 0))
+    return "Integer out of bounds";
+  switch (obj->atype) {
+
+    case ATYPE_IPV4:
+      break;
+
+    case ATYPE_IPV6:
+      break;
+
+    case ATYPE_DOMAINNAME:
+      {
+        const char *msg;
+        if (NULL != (msg = domainname_check(obj->bind_addr_domainname)))
+          return msg;
+      }
+      break;
+
+    default:
+        return "Bad tag for union";
+      break;
+  }
+  return NULL;
+}
+
+ssize_t
+socks5_server_reply_encoded_len(const socks5_server_reply_t *obj)
+{
+  ssize_t result = 0;
+
+  if (NULL != socks5_server_reply_check(obj))
+     return -1;
+
+
+  /* Length of u8 version IN [5] */
+  result += 1;
+
+  /* Length of u8 reply */
+  result += 1;
+
+  /* Length of u8 reserved IN [0] */
+  result += 1;
+
+  /* Length of u8 atype */
+  result += 1;
+  switch (obj->atype) {
+
+    case ATYPE_IPV4:
+
+      /* Length of u32 bind_addr_ipv4 */
+      result += 4;
+      break;
+
+    case ATYPE_IPV6:
+
+      /* Length of u8 bind_addr_ipv6[16] */
+      result += 16;
+      break;
+
+    case ATYPE_DOMAINNAME:
+
+      /* Length of struct domainname bind_addr_domainname */
+      result += domainname_encoded_len(obj->bind_addr_domainname);
+      break;
+
+    default:
+      trunnel_assert(0);
+      break;
+  }
+
+  /* Length of u16 bind_port */
+  result += 2;
+  return result;
+}
+int
+socks5_server_reply_clear_errors(socks5_server_reply_t *obj)
+{
+  int r = obj->trunnel_error_code_;
+  obj->trunnel_error_code_ = 0;
+  return r;
+}
+ssize_t
+socks5_server_reply_encode(uint8_t *output, const size_t avail, const socks5_server_reply_t *obj)
+{
+  ssize_t result = 0;
+  size_t written = 0;
+  uint8_t *ptr = output;
+  const char *msg;
+#ifdef TRUNNEL_CHECK_ENCODED_LEN
+  const ssize_t encoded_len = socks5_server_reply_encoded_len(obj);
+#endif
+
+  if (NULL != (msg = socks5_server_reply_check(obj)))
+    goto check_failed;
+
+#ifdef TRUNNEL_CHECK_ENCODED_LEN
+  trunnel_assert(encoded_len >= 0);
+#endif
+
+  /* Encode u8 version IN [5] */
+  trunnel_assert(written <= avail);
+  if (avail - written < 1)
+    goto truncated;
+  trunnel_set_uint8(ptr, (obj->version));
+  written += 1; ptr += 1;
+
+  /* Encode u8 reply */
+  trunnel_assert(written <= avail);
+  if (avail - written < 1)
+    goto truncated;
+  trunnel_set_uint8(ptr, (obj->reply));
+  written += 1; ptr += 1;
+
+  /* Encode u8 reserved IN [0] */
+  trunnel_assert(written <= avail);
+  if (avail - written < 1)
+    goto truncated;
+  trunnel_set_uint8(ptr, (obj->reserved));
+  written += 1; ptr += 1;
+
+  /* Encode u8 atype */
+  trunnel_assert(written <= avail);
+  if (avail - written < 1)
+    goto truncated;
+  trunnel_set_uint8(ptr, (obj->atype));
+  written += 1; ptr += 1;
+
+  /* Encode union bind_addr[atype] */
+  trunnel_assert(written <= avail);
+  switch (obj->atype) {
+
+    case ATYPE_IPV4:
+
+      /* Encode u32 bind_addr_ipv4 */
+      trunnel_assert(written <= avail);
+      if (avail - written < 4)
+        goto truncated;
+      trunnel_set_uint32(ptr, trunnel_htonl(obj->bind_addr_ipv4));
+      written += 4; ptr += 4;
+      break;
+
+    case ATYPE_IPV6:
+
+      /* Encode u8 bind_addr_ipv6[16] */
+      trunnel_assert(written <= avail);
+      if (avail - written < 16)
+        goto truncated;
+      memcpy(ptr, obj->bind_addr_ipv6, 16);
+      written += 16; ptr += 16;
+      break;
+
+    case ATYPE_DOMAINNAME:
+
+      /* Encode struct domainname bind_addr_domainname */
+      trunnel_assert(written <= avail);
+      result = domainname_encode(ptr, avail - written, obj->bind_addr_domainname);
+      if (result < 0)
+        goto fail; /* XXXXXXX !*/
+      written += result; ptr += result;
+      break;
+
+    default:
+      trunnel_assert(0);
+      break;
+  }
+
+  /* Encode u16 bind_port */
+  trunnel_assert(written <= avail);
+  if (avail - written < 2)
+    goto truncated;
+  trunnel_set_uint16(ptr, trunnel_htons(obj->bind_port));
+  written += 2; ptr += 2;
+
+
+  trunnel_assert(ptr == output + written);
+#ifdef TRUNNEL_CHECK_ENCODED_LEN
+  {
+    trunnel_assert(encoded_len >= 0);
+    trunnel_assert((size_t)encoded_len == written);
+  }
+
+#endif
+
+  return written;
+
+ truncated:
+  result = -2;
+  goto fail;
+ check_failed:
+  (void)msg;
+  result = -1;
+  goto fail;
+ fail:
+  trunnel_assert(result < 0);
+  return result;
+}
+
+/** As socks5_server_reply_parse(), but do not allocate the output
+ * object.
+ */
+static ssize_t
+socks5_server_reply_parse_into(socks5_server_reply_t *obj, const uint8_t *input, const size_t len_in)
+{
+  const uint8_t *ptr = input;
+  size_t remaining = len_in;
+  ssize_t result = 0;
+  (void)result;
+
+  /* Parse u8 version IN [5] */
+  CHECK_REMAINING(1, truncated);
+  obj->version = (trunnel_get_uint8(ptr));
+  remaining -= 1; ptr += 1;
+  if (! (obj->version == 5))
+    goto fail;
+
+  /* Parse u8 reply */
+  CHECK_REMAINING(1, truncated);
+  obj->reply = (trunnel_get_uint8(ptr));
+  remaining -= 1; ptr += 1;
+
+  /* Parse u8 reserved IN [0] */
+  CHECK_REMAINING(1, truncated);
+  obj->reserved = (trunnel_get_uint8(ptr));
+  remaining -= 1; ptr += 1;
+  if (! (obj->reserved == 0))
+    goto fail;
+
+  /* Parse u8 atype */
+  CHECK_REMAINING(1, truncated);
+  obj->atype = (trunnel_get_uint8(ptr));
+  remaining -= 1; ptr += 1;
+
+  /* Parse union bind_addr[atype] */
+  switch (obj->atype) {
+
+    case ATYPE_IPV4:
+
+      /* Parse u32 bind_addr_ipv4 */
+      CHECK_REMAINING(4, truncated);
+      obj->bind_addr_ipv4 = trunnel_ntohl(trunnel_get_uint32(ptr));
+      remaining -= 4; ptr += 4;
+      break;
+
+    case ATYPE_IPV6:
+
+      /* Parse u8 bind_addr_ipv6[16] */
+      CHECK_REMAINING(16, truncated);
+      memcpy(obj->bind_addr_ipv6, ptr, 16);
+      remaining -= 16; ptr += 16;
+      break;
+
+    case ATYPE_DOMAINNAME:
+
+      /* Parse struct domainname bind_addr_domainname */
+      result = domainname_parse(&obj->bind_addr_domainname, ptr, remaining);
+      if (result < 0)
+        goto relay_fail;
+      trunnel_assert((size_t)result <= remaining);
+      remaining -= result; ptr += result;
+      break;
+
+    default:
+      goto fail;
+      break;
+  }
+
+  /* Parse u16 bind_port */
+  CHECK_REMAINING(2, truncated);
+  obj->bind_port = trunnel_ntohs(trunnel_get_uint16(ptr));
+  remaining -= 2; ptr += 2;
+  trunnel_assert(ptr + remaining == input + len_in);
+  return len_in - remaining;
+
+ truncated:
+  return -2;
+ relay_fail:
+  trunnel_assert(result < 0);
+  return result;
+ fail:
+  result = -1;
+  return result;
+}
+
+ssize_t
+socks5_server_reply_parse(socks5_server_reply_t **output, const uint8_t *input, const size_t len_in)
+{
+  ssize_t result;
+  *output = socks5_server_reply_new();
+  if (NULL == *output)
+    return -1;
+  result = socks5_server_reply_parse_into(*output, input, len_in);
+  if (result < 0) {
+    socks5_server_reply_free(*output);
+    *output = NULL;
+  }
+  return result;
+}

src/trunnel/socks5.h

@@ -0,0 +1,995 @@
+/* socks5.h -- generated by Trunnel v1.5.2.
+ * https://gitweb.torproject.org/trunnel.git
+ * You probably shouldn't edit this file.
+ */
+#ifndef TRUNNEL_SOCKS5_H
+#define TRUNNEL_SOCKS5_H
+
+#include <stdint.h>
+#include "trunnel.h"
+
+#define CMD_CONNECT 1
+#define CMD_BIND 2
+#define CMD_UDP_ASSOCIATE 3
+#define CMD_RESOLVE 240
+#define CMD_RESOLVE_PTR 241
+#define ATYPE_IPV4 1
+#define ATYPE_IPV6 4
+#define ATYPE_DOMAINNAME 3
+#if !defined(TRUNNEL_OPAQUE) && !defined(TRUNNEL_OPAQUE_DOMAINNAME)
+struct domainname_st {
+  uint8_t len;
+  trunnel_string_t name;
+  uint8_t trunnel_error_code_;
+};
+#endif
+typedef struct domainname_st domainname_t;
+#if !defined(TRUNNEL_OPAQUE) && !defined(TRUNNEL_OPAQUE_SOCKS4_CLIENT_REQUEST)
+struct socks4_client_request_st {
+  uint8_t version;
+  uint8_t command;
+  uint16_t port;
+  uint32_t addr;
+  char *username;
+  char *socks4a_addr_hostname;
+  uint8_t trunnel_error_code_;
+};
+#endif
+typedef struct socks4_client_request_st socks4_client_request_t;
+#if !defined(TRUNNEL_OPAQUE) && !defined(TRUNNEL_OPAQUE_SOCKS4_SERVER_REPLY)
+struct socks4_server_reply_st {
+  uint8_t version;
+  uint8_t status;
+  uint16_t port;
+  uint32_t addr;
+  uint8_t trunnel_error_code_;
+};
+#endif
+typedef struct socks4_server_reply_st socks4_server_reply_t;
+#if !defined(TRUNNEL_OPAQUE) && !defined(TRUNNEL_OPAQUE_SOCKS5_CLIENT_USERPASS_AUTH)
+struct socks5_client_userpass_auth_st {
+  uint8_t version;
+  uint8_t username_len;
+  trunnel_string_t username;
+  uint8_t passwd_len;
+  trunnel_string_t passwd;
+  uint8_t trunnel_error_code_;
+};
+#endif
+typedef struct socks5_client_userpass_auth_st socks5_client_userpass_auth_t;
+#if !defined(TRUNNEL_OPAQUE) && !defined(TRUNNEL_OPAQUE_SOCKS5_CLIENT_VERSION)
+struct socks5_client_version_st {
+  uint8_t version;
+  uint8_t n_methods;
+  TRUNNEL_DYNARRAY_HEAD(, uint8_t) methods;
+  uint8_t trunnel_error_code_;
+};
+#endif
+typedef struct socks5_client_version_st socks5_client_version_t;
+#if !defined(TRUNNEL_OPAQUE) && !defined(TRUNNEL_OPAQUE_SOCKS5_SERVER_METHOD)
+struct socks5_server_method_st {
+  uint8_t version;
+  uint8_t method;
+  uint8_t trunnel_error_code_;
+};
+#endif
+typedef struct socks5_server_method_st socks5_server_method_t;
+#if !defined(TRUNNEL_OPAQUE) && !defined(TRUNNEL_OPAQUE_SOCKS5_SERVER_USERPASS_AUTH)
+struct socks5_server_userpass_auth_st {
+  uint8_t version;
+  uint8_t status;
+  uint8_t trunnel_error_code_;
+};
+#endif
+typedef struct socks5_server_userpass_auth_st socks5_server_userpass_auth_t;
+#if !defined(TRUNNEL_OPAQUE) && !defined(TRUNNEL_OPAQUE_SOCKS5_CLIENT_REQUEST)
+struct socks5_client_request_st {
+  uint8_t version;
+  uint8_t command;
+  uint8_t reserved;
+  uint8_t atype;
+  uint32_t dest_addr_ipv4;
+  uint8_t dest_addr_ipv6[16];
+  struct domainname_st *dest_addr_domainname;
+  uint16_t dest_port;
+  uint8_t trunnel_error_code_;
+};
+#endif
+typedef struct socks5_client_request_st socks5_client_request_t;
+#if !defined(TRUNNEL_OPAQUE) && !defined(TRUNNEL_OPAQUE_SOCKS5_SERVER_REPLY)
+struct socks5_server_reply_st {
+  uint8_t version;
+  uint8_t reply;
+  uint8_t reserved;
+  uint8_t atype;
+  uint32_t bind_addr_ipv4;
+  uint8_t bind_addr_ipv6[16];
+  struct domainname_st *bind_addr_domainname;
+  uint16_t bind_port;
+  uint8_t trunnel_error_code_;
+};
+#endif
+typedef struct socks5_server_reply_st socks5_server_reply_t;
+/** Return a newly allocated domainname with all elements set to zero.
+ */
+domainname_t *domainname_new(void);
+/** Release all storage held by the domainname in 'victim'. (Do
+ * nothing if 'victim' is NULL.)
+ */
+void domainname_free(domainname_t *victim);
+/** Try to parse a domainname from the buffer in 'input', using up to
+ * 'len_in' bytes from the input buffer. On success, return the number
+ * of bytes consumed and set *output to the newly allocated
+ * domainname_t. On failure, return -2 if the input appears truncated,
+ * and -1 if the input is otherwise invalid.
+ */
+ssize_t domainname_parse(domainname_t **output, const uint8_t *input, const size_t len_in);
+/** Return the number of bytes we expect to need to encode the
+ * domainname in 'obj'. On failure, return a negative value. Note that
+ * this value may be an overestimate, and can even be an underestimate
+ * for certain unencodeable objects.
+ */
+ssize_t domainname_encoded_len(const domainname_t *obj);
+/** Try to encode the domainname from 'input' into the buffer at
+ * 'output', using up to 'avail' bytes of the output buffer. On
+ * success, return the number of bytes used. On failure, return -2 if
+ * the buffer was not long enough, and -1 if the input was invalid.
+ */
+ssize_t domainname_encode(uint8_t *output, size_t avail, const domainname_t *input);
+/** Check whether the internal state of the domainname in 'obj' is
+ * consistent. Return NULL if it is, and a short message if it is not.
+ */
+const char *domainname_check(const domainname_t *obj);
+/** Clear any errors that were set on the object 'obj' by its setter
+ * functions. Return true iff errors were cleared.
+ */
+int domainname_clear_errors(domainname_t *obj);
+/** Return the value of the len field of the domainname_t in 'inp'
+ */
+uint8_t domainname_get_len(const domainname_t *inp);
+/** Set the value of the len field of the domainname_t in 'inp' to
+ * 'val'. Return 0 on success; return -1 and set the error code on
+ * 'inp' on failure.
+ */
+int domainname_set_len(domainname_t *inp, uint8_t val);
+/** Return the length of the dynamic array holding the name field of
+ * the domainname_t in 'inp'.
+ */
+size_t domainname_getlen_name(const domainname_t *inp);
+/** Return the element at position 'idx' of the dynamic array field
+ * name of the domainname_t in 'inp'.
+ */
+char domainname_get_name(domainname_t *inp, size_t idx);
+/** As domainname_get_name, but take and return a const pointer
+ */
+char domainname_getconst_name(const domainname_t *inp, size_t idx);
+/** Change the element at position 'idx' of the dynamic array field
+ * name of the domainname_t in 'inp', so that it will hold the value
+ * 'elt'.
+ */
+int domainname_set_name(domainname_t *inp, size_t idx, char elt);
+/** Append a new element 'elt' to the dynamic array field name of the
+ * domainname_t in 'inp'.
+ */
+int domainname_add_name(domainname_t *inp, char elt);
+/** Return a pointer to the variable-length array field name of 'inp'.
+ */
+char * domainname_getarray_name(domainname_t *inp);
+/** As domainname_get_name, but take and return a const pointer
+ */
+const char  * domainname_getconstarray_name(const domainname_t *inp);
+/** Change the length of the variable-length array field name of 'inp'
+ * to 'newlen'.Fill extra elements with 0. Return 0 on success; return
+ * -1 and set the error code on 'inp' on failure.
+ */
+int domainname_setlen_name(domainname_t *inp, size_t newlen);
+/** Return the value of the name field of a domainname_t as a NUL-
+ * terminated string.
+ */
+const char * domainname_getstr_name(domainname_t *inp);
+/** Set the value of the name field of a domainname_t to a given
+ * string of length 'len'. Return 0 on success; return -1 and set the
+ * error code on 'inp' on failure.
+ */
+int domainname_setstr0_name(domainname_t *inp, const char *val, size_t len);
+/** Set the value of the name field of a domainname_t to a given NUL-
+ * terminated string. Return 0 on success; return -1 and set the error
+ * code on 'inp' on failure.
+ */
+int domainname_setstr_name(domainname_t *inp, const char *val);
+/** Return a newly allocated socks4_client_request with all elements
+ * set to zero.
+ */
+socks4_client_request_t *socks4_client_request_new(void);
+/** Release all storage held by the socks4_client_request in 'victim'.
+ * (Do nothing if 'victim' is NULL.)
+ */
+void socks4_client_request_free(socks4_client_request_t *victim);
+/** Try to parse a socks4_client_request from the buffer in 'input',
+ * using up to 'len_in' bytes from the input buffer. On success,
+ * return the number of bytes consumed and set *output to the newly
+ * allocated socks4_client_request_t. On failure, return -2 if the
+ * input appears truncated, and -1 if the input is otherwise invalid.
+ */
+ssize_t socks4_client_request_parse(socks4_client_request_t **output, const uint8_t *input, const size_t len_in);
+/** Return the number of bytes we expect to need to encode the
+ * socks4_client_request in 'obj'. On failure, return a negative
+ * value. Note that this value may be an overestimate, and can even be
+ * an underestimate for certain unencodeable objects.
+ */
+ssize_t socks4_client_request_encoded_len(const socks4_client_request_t *obj);
+/** Try to encode the socks4_client_request from 'input' into the
+ * buffer at 'output', using up to 'avail' bytes of the output buffer.
+ * On success, return the number of bytes used. On failure, return -2
+ * if the buffer was not long enough, and -1 if the input was invalid.
+ */
+ssize_t socks4_client_request_encode(uint8_t *output, size_t avail, const socks4_client_request_t *input);
+/** Check whether the internal state of the socks4_client_request in
+ * 'obj' is consistent. Return NULL if it is, and a short message if
+ * it is not.
+ */
+const char *socks4_client_request_check(const socks4_client_request_t *obj);
+/** Clear any errors that were set on the object 'obj' by its setter
+ * functions. Return true iff errors were cleared.
+ */
+int socks4_client_request_clear_errors(socks4_client_request_t *obj);
+/** Return the value of the version field of the
+ * socks4_client_request_t in 'inp'
+ */
+uint8_t socks4_client_request_get_version(const socks4_client_request_t *inp);
+/** Set the value of the version field of the socks4_client_request_t
+ * in 'inp' to 'val'. Return 0 on success; return -1 and set the error
+ * code on 'inp' on failure.
+ */
+int socks4_client_request_set_version(socks4_client_request_t *inp, uint8_t val);
+/** Return the value of the command field of the
+ * socks4_client_request_t in 'inp'
+ */
+uint8_t socks4_client_request_get_command(const socks4_client_request_t *inp);
+/** Set the value of the command field of the socks4_client_request_t
+ * in 'inp' to 'val'. Return 0 on success; return -1 and set the error
+ * code on 'inp' on failure.
+ */
+int socks4_client_request_set_command(socks4_client_request_t *inp, uint8_t val);
+/** Return the value of the port field of the socks4_client_request_t
+ * in 'inp'
+ */
+uint16_t socks4_client_request_get_port(const socks4_client_request_t *inp);
+/** Set the value of the port field of the socks4_client_request_t in
+ * 'inp' to 'val'. Return 0 on success; return -1 and set the error
+ * code on 'inp' on failure.
+ */
+int socks4_client_request_set_port(socks4_client_request_t *inp, uint16_t val);
+/** Return the value of the addr field of the socks4_client_request_t
+ * in 'inp'
+ */
+uint32_t socks4_client_request_get_addr(const socks4_client_request_t *inp);
+/** Set the value of the addr field of the socks4_client_request_t in
+ * 'inp' to 'val'. Return 0 on success; return -1 and set the error
+ * code on 'inp' on failure.
+ */
+int socks4_client_request_set_addr(socks4_client_request_t *inp, uint32_t val);
+/** Return the value of the username field of the
+ * socks4_client_request_t in 'inp'
+ */
+const char * socks4_client_request_get_username(const socks4_client_request_t *inp);
+/** Set the value of the username field of the socks4_client_request_t
+ * in 'inp' to 'val'. Free the old value if any. Does not steal the
+ * reference to 'val'.Return 0 on success; return -1 and set the error
+ * code on 'inp' on failure.
+ */
+int socks4_client_request_set_username(socks4_client_request_t *inp, const char *val);
+/** Return the value of the socks4a_addr_hostname field of the
+ * socks4_client_request_t in 'inp'
+ */
+const char * socks4_client_request_get_socks4a_addr_hostname(const socks4_client_request_t *inp);
+/** Set the value of the socks4a_addr_hostname field of the
+ * socks4_client_request_t in 'inp' to 'val'. Free the old value if
+ * any. Does not steal the reference to 'val'.Return 0 on success;
+ * return -1 and set the error code on 'inp' on failure.
+ */
+int socks4_client_request_set_socks4a_addr_hostname(socks4_client_request_t *inp, const char *val);
+/** Return a newly allocated socks4_server_reply with all elements set
+ * to zero.
+ */
+socks4_server_reply_t *socks4_server_reply_new(void);
+/** Release all storage held by the socks4_server_reply in 'victim'.
+ * (Do nothing if 'victim' is NULL.)
+ */
+void socks4_server_reply_free(socks4_server_reply_t *victim);
+/** Try to parse a socks4_server_reply from the buffer in 'input',
+ * using up to 'len_in' bytes from the input buffer. On success,
+ * return the number of bytes consumed and set *output to the newly
+ * allocated socks4_server_reply_t. On failure, return -2 if the input
+ * appears truncated, and -1 if the input is otherwise invalid.
+ */
+ssize_t socks4_server_reply_parse(socks4_server_reply_t **output, const uint8_t *input, const size_t len_in);
+/** Return the number of bytes we expect to need to encode the
+ * socks4_server_reply in 'obj'. On failure, return a negative value.
+ * Note that this value may be an overestimate, and can even be an
+ * underestimate for certain unencodeable objects.
+ */
+ssize_t socks4_server_reply_encoded_len(const socks4_server_reply_t *obj);
+/** Try to encode the socks4_server_reply from 'input' into the buffer
+ * at 'output', using up to 'avail' bytes of the output buffer. On
+ * success, return the number of bytes used. On failure, return -2 if
+ * the buffer was not long enough, and -1 if the input was invalid.
+ */
+ssize_t socks4_server_reply_encode(uint8_t *output, size_t avail, const socks4_server_reply_t *input);
+/** Check whether the internal state of the socks4_server_reply in
+ * 'obj' is consistent. Return NULL if it is, and a short message if
+ * it is not.
+ */
+const char *socks4_server_reply_check(const socks4_server_reply_t *obj);
+/** Clear any errors that were set on the object 'obj' by its setter
+ * functions. Return true iff errors were cleared.
+ */
+int socks4_server_reply_clear_errors(socks4_server_reply_t *obj);
+/** Return the value of the version field of the socks4_server_reply_t
+ * in 'inp'
+ */
+uint8_t socks4_server_reply_get_version(const socks4_server_reply_t *inp);
+/** Set the value of the version field of the socks4_server_reply_t in
+ * 'inp' to 'val'. Return 0 on success; return -1 and set the error
+ * code on 'inp' on failure.
+ */
+int socks4_server_reply_set_version(socks4_server_reply_t *inp, uint8_t val);
+/** Return the value of the status field of the socks4_server_reply_t
+ * in 'inp'
+ */
+uint8_t socks4_server_reply_get_status(const socks4_server_reply_t *inp);
+/** Set the value of the status field of the socks4_server_reply_t in
+ * 'inp' to 'val'. Return 0 on success; return -1 and set the error
+ * code on 'inp' on failure.
+ */
+int socks4_server_reply_set_status(socks4_server_reply_t *inp, uint8_t val);
+/** Return the value of the port field of the socks4_server_reply_t in
+ * 'inp'
+ */
+uint16_t socks4_server_reply_get_port(const socks4_server_reply_t *inp);
+/** Set the value of the port field of the socks4_server_reply_t in
+ * 'inp' to 'val'. Return 0 on success; return -1 and set the error
+ * code on 'inp' on failure.
+ */
+int socks4_server_reply_set_port(socks4_server_reply_t *inp, uint16_t val);
+/** Return the value of the addr field of the socks4_server_reply_t in
+ * 'inp'
+ */
+uint32_t socks4_server_reply_get_addr(const socks4_server_reply_t *inp);
+/** Set the value of the addr field of the socks4_server_reply_t in
+ * 'inp' to 'val'. Return 0 on success; return -1 and set the error
+ * code on 'inp' on failure.
+ */
+int socks4_server_reply_set_addr(socks4_server_reply_t *inp, uint32_t val);
+/** Return a newly allocated socks5_client_userpass_auth with all
+ * elements set to zero.
+ */
+socks5_client_userpass_auth_t *socks5_client_userpass_auth_new(void);
+/** Release all storage held by the socks5_client_userpass_auth in
+ * 'victim'. (Do nothing if 'victim' is NULL.)
+ */
+void socks5_client_userpass_auth_free(socks5_client_userpass_auth_t *victim);
+/** Try to parse a socks5_client_userpass_auth from the buffer in
+ * 'input', using up to 'len_in' bytes from the input buffer. On
+ * success, return the number of bytes consumed and set *output to the
+ * newly allocated socks5_client_userpass_auth_t. On failure, return
+ * -2 if the input appears truncated, and -1 if the input is otherwise
+ * invalid.
+ */
+ssize_t socks5_client_userpass_auth_parse(socks5_client_userpass_auth_t **output, const uint8_t *input, const size_t len_in);
+/** Return the number of bytes we expect to need to encode the
+ * socks5_client_userpass_auth in 'obj'. On failure, return a negative
+ * value. Note that this value may be an overestimate, and can even be
+ * an underestimate for certain unencodeable objects.
+ */
+ssize_t socks5_client_userpass_auth_encoded_len(const socks5_client_userpass_auth_t *obj);
+/** Try to encode the socks5_client_userpass_auth from 'input' into
+ * the buffer at 'output', using up to 'avail' bytes of the output
+ * buffer. On success, return the number of bytes used. On failure,
+ * return -2 if the buffer was not long enough, and -1 if the input
+ * was invalid.
+ */
+ssize_t socks5_client_userpass_auth_encode(uint8_t *output, size_t avail, const socks5_client_userpass_auth_t *input);
+/** Check whether the internal state of the
+ * socks5_client_userpass_auth in 'obj' is consistent. Return NULL if
+ * it is, and a short message if it is not.
+ */
+const char *socks5_client_userpass_auth_check(const socks5_client_userpass_auth_t *obj);
+/** Clear any errors that were set on the object 'obj' by its setter
+ * functions. Return true iff errors were cleared.
+ */
+int socks5_client_userpass_auth_clear_errors(socks5_client_userpass_auth_t *obj);
+/** Return the value of the version field of the
+ * socks5_client_userpass_auth_t in 'inp'
+ */
+uint8_t socks5_client_userpass_auth_get_version(const socks5_client_userpass_auth_t *inp);
+/** Set the value of the version field of the
+ * socks5_client_userpass_auth_t in 'inp' to 'val'. Return 0 on
+ * success; return -1 and set the error code on 'inp' on failure.
+ */
+int socks5_client_userpass_auth_set_version(socks5_client_userpass_auth_t *inp, uint8_t val);
+/** Return the value of the username_len field of the
+ * socks5_client_userpass_auth_t in 'inp'
+ */
+uint8_t socks5_client_userpass_auth_get_username_len(const socks5_client_userpass_auth_t *inp);
+/** Set the value of the username_len field of the
+ * socks5_client_userpass_auth_t in 'inp' to 'val'. Return 0 on
+ * success; return -1 and set the error code on 'inp' on failure.
+ */
+int socks5_client_userpass_auth_set_username_len(socks5_client_userpass_auth_t *inp, uint8_t val);
+/** Return the length of the dynamic array holding the username field
+ * of the socks5_client_userpass_auth_t in 'inp'.
+ */
+size_t socks5_client_userpass_auth_getlen_username(const socks5_client_userpass_auth_t *inp);
+/** Return the element at position 'idx' of the dynamic array field
+ * username of the socks5_client_userpass_auth_t in 'inp'.
+ */
+char socks5_client_userpass_auth_get_username(socks5_client_userpass_auth_t *inp, size_t idx);
+/** As socks5_client_userpass_auth_get_username, but take and return a
+ * const pointer
+ */
+char socks5_client_userpass_auth_getconst_username(const socks5_client_userpass_auth_t *inp, size_t idx);
+/** Change the element at position 'idx' of the dynamic array field
+ * username of the socks5_client_userpass_auth_t in 'inp', so that it
+ * will hold the value 'elt'.
+ */
+int socks5_client_userpass_auth_set_username(socks5_client_userpass_auth_t *inp, size_t idx, char elt);
+/** Append a new element 'elt' to the dynamic array field username of
+ * the socks5_client_userpass_auth_t in 'inp'.
+ */
+int socks5_client_userpass_auth_add_username(socks5_client_userpass_auth_t *inp, char elt);
+/** Return a pointer to the variable-length array field username of
+ * 'inp'.
+ */
+char * socks5_client_userpass_auth_getarray_username(socks5_client_userpass_auth_t *inp);
+/** As socks5_client_userpass_auth_get_username, but take and return a
+ * const pointer
+ */
+const char  * socks5_client_userpass_auth_getconstarray_username(const socks5_client_userpass_auth_t *inp);
+/** Change the length of the variable-length array field username of
+ * 'inp' to 'newlen'.Fill extra elements with 0. Return 0 on success;
+ * return -1 and set the error code on 'inp' on failure.
+ */
+int socks5_client_userpass_auth_setlen_username(socks5_client_userpass_auth_t *inp, size_t newlen);
+/** Return the value of the username field of a
+ * socks5_client_userpass_auth_t as a NUL-terminated string.
+ */
+const char * socks5_client_userpass_auth_getstr_username(socks5_client_userpass_auth_t *inp);
+/** Set the value of the username field of a
+ * socks5_client_userpass_auth_t to a given string of length 'len'.
+ * Return 0 on success; return -1 and set the error code on 'inp' on
+ * failure.
+ */
+int socks5_client_userpass_auth_setstr0_username(socks5_client_userpass_auth_t *inp, const char *val, size_t len);
+/** Set the value of the username field of a
+ * socks5_client_userpass_auth_t to a given NUL-terminated string.
+ * Return 0 on success; return -1 and set the error code on 'inp' on
+ * failure.
+ */
+int socks5_client_userpass_auth_setstr_username(socks5_client_userpass_auth_t *inp, const char *val);
+/** Return the value of the passwd_len field of the
+ * socks5_client_userpass_auth_t in 'inp'
+ */
+uint8_t socks5_client_userpass_auth_get_passwd_len(const socks5_client_userpass_auth_t *inp);
+/** Set the value of the passwd_len field of the
+ * socks5_client_userpass_auth_t in 'inp' to 'val'. Return 0 on
+ * success; return -1 and set the error code on 'inp' on failure.
+ */
+int socks5_client_userpass_auth_set_passwd_len(socks5_client_userpass_auth_t *inp, uint8_t val);
+/** Return the length of the dynamic array holding the passwd field of
+ * the socks5_client_userpass_auth_t in 'inp'.
+ */
+size_t socks5_client_userpass_auth_getlen_passwd(const socks5_client_userpass_auth_t *inp);
+/** Return the element at position 'idx' of the dynamic array field
+ * passwd of the socks5_client_userpass_auth_t in 'inp'.
+ */
+char socks5_client_userpass_auth_get_passwd(socks5_client_userpass_auth_t *inp, size_t idx);
+/** As socks5_client_userpass_auth_get_passwd, but take and return a
+ * const pointer
+ */
+char socks5_client_userpass_auth_getconst_passwd(const socks5_client_userpass_auth_t *inp, size_t idx);
+/** Change the element at position 'idx' of the dynamic array field
+ * passwd of the socks5_client_userpass_auth_t in 'inp', so that it
+ * will hold the value 'elt'.
+ */
+int socks5_client_userpass_auth_set_passwd(socks5_client_userpass_auth_t *inp, size_t idx, char elt);
+/** Append a new element 'elt' to the dynamic array field passwd of
+ * the socks5_client_userpass_auth_t in 'inp'.
+ */
+int socks5_client_userpass_auth_add_passwd(socks5_client_userpass_auth_t *inp, char elt);
+/** Return a pointer to the variable-length array field passwd of
+ * 'inp'.
+ */
+char * socks5_client_userpass_auth_getarray_passwd(socks5_client_userpass_auth_t *inp);
+/** As socks5_client_userpass_auth_get_passwd, but take and return a
+ * const pointer
+ */
+const char  * socks5_client_userpass_auth_getconstarray_passwd(const socks5_client_userpass_auth_t *inp);
+/** Change the length of the variable-length array field passwd of
+ * 'inp' to 'newlen'.Fill extra elements with 0. Return 0 on success;
+ * return -1 and set the error code on 'inp' on failure.
+ */
+int socks5_client_userpass_auth_setlen_passwd(socks5_client_userpass_auth_t *inp, size_t newlen);
+/** Return the value of the passwd field of a
+ * socks5_client_userpass_auth_t as a NUL-terminated string.
+ */
+const char * socks5_client_userpass_auth_getstr_passwd(socks5_client_userpass_auth_t *inp);
+/** Set the value of the passwd field of a
+ * socks5_client_userpass_auth_t to a given string of length 'len'.
+ * Return 0 on success; return -1 and set the error code on 'inp' on
+ * failure.
+ */
+int socks5_client_userpass_auth_setstr0_passwd(socks5_client_userpass_auth_t *inp, const char *val, size_t len);
+/** Set the value of the passwd field of a
+ * socks5_client_userpass_auth_t to a given NUL-terminated string.
+ * Return 0 on success; return -1 and set the error code on 'inp' on
+ * failure.
+ */
+int socks5_client_userpass_auth_setstr_passwd(socks5_client_userpass_auth_t *inp, const char *val);
+/** Return a newly allocated socks5_client_version with all elements
+ * set to zero.
+ */
+socks5_client_version_t *socks5_client_version_new(void);
+/** Release all storage held by the socks5_client_version in 'victim'.
+ * (Do nothing if 'victim' is NULL.)
+ */
+void socks5_client_version_free(socks5_client_version_t *victim);
+/** Try to parse a socks5_client_version from the buffer in 'input',
+ * using up to 'len_in' bytes from the input buffer. On success,
+ * return the number of bytes consumed and set *output to the newly
+ * allocated socks5_client_version_t. On failure, return -2 if the
+ * input appears truncated, and -1 if the input is otherwise invalid.
+ */
+ssize_t socks5_client_version_parse(socks5_client_version_t **output, const uint8_t *input, const size_t len_in);
+/** Return the number of bytes we expect to need to encode the
+ * socks5_client_version in 'obj'. On failure, return a negative
+ * value. Note that this value may be an overestimate, and can even be
+ * an underestimate for certain unencodeable objects.
+ */
+ssize_t socks5_client_version_encoded_len(const socks5_client_version_t *obj);
+/** Try to encode the socks5_client_version from 'input' into the
+ * buffer at 'output', using up to 'avail' bytes of the output buffer.
+ * On success, return the number of bytes used. On failure, return -2
+ * if the buffer was not long enough, and -1 if the input was invalid.
+ */
+ssize_t socks5_client_version_encode(uint8_t *output, size_t avail, const socks5_client_version_t *input);
+/** Check whether the internal state of the socks5_client_version in
+ * 'obj' is consistent. Return NULL if it is, and a short message if
+ * it is not.
+ */
+const char *socks5_client_version_check(const socks5_client_version_t *obj);
+/** Clear any errors that were set on the object 'obj' by its setter
+ * functions. Return true iff errors were cleared.
+ */
+int socks5_client_version_clear_errors(socks5_client_version_t *obj);
+/** Return the value of the version field of the
+ * socks5_client_version_t in 'inp'
+ */
+uint8_t socks5_client_version_get_version(const socks5_client_version_t *inp);
+/** Set the value of the version field of the socks5_client_version_t
+ * in 'inp' to 'val'. Return 0 on success; return -1 and set the error
+ * code on 'inp' on failure.
+ */
+int socks5_client_version_set_version(socks5_client_version_t *inp, uint8_t val);
+/** Return the value of the n_methods field of the
+ * socks5_client_version_t in 'inp'
+ */
+uint8_t socks5_client_version_get_n_methods(const socks5_client_version_t *inp);
+/** Set the value of the n_methods field of the
+ * socks5_client_version_t in 'inp' to 'val'. Return 0 on success;
+ * return -1 and set the error code on 'inp' on failure.
+ */
+int socks5_client_version_set_n_methods(socks5_client_version_t *inp, uint8_t val);
+/** Return the length of the dynamic array holding the methods field
+ * of the socks5_client_version_t in 'inp'.
+ */
+size_t socks5_client_version_getlen_methods(const socks5_client_version_t *inp);
+/** Return the element at position 'idx' of the dynamic array field
+ * methods of the socks5_client_version_t in 'inp'.
+ */
+uint8_t socks5_client_version_get_methods(socks5_client_version_t *inp, size_t idx);
+/** As socks5_client_version_get_methods, but take and return a const
+ * pointer
+ */
+uint8_t socks5_client_version_getconst_methods(const socks5_client_version_t *inp, size_t idx);
+/** Change the element at position 'idx' of the dynamic array field
+ * methods of the socks5_client_version_t in 'inp', so that it will
+ * hold the value 'elt'.
+ */
+int socks5_client_version_set_methods(socks5_client_version_t *inp, size_t idx, uint8_t elt);
+/** Append a new element 'elt' to the dynamic array field methods of
+ * the socks5_client_version_t in 'inp'.
+ */
+int socks5_client_version_add_methods(socks5_client_version_t *inp, uint8_t elt);
+/** Return a pointer to the variable-length array field methods of
+ * 'inp'.
+ */
+uint8_t * socks5_client_version_getarray_methods(socks5_client_version_t *inp);
+/** As socks5_client_version_get_methods, but take and return a const
+ * pointer
+ */
+const uint8_t  * socks5_client_version_getconstarray_methods(const socks5_client_version_t *inp);
+/** Change the length of the variable-length array field methods of
+ * 'inp' to 'newlen'.Fill extra elements with 0. Return 0 on success;
+ * return -1 and set the error code on 'inp' on failure.
+ */
+int socks5_client_version_setlen_methods(socks5_client_version_t *inp, size_t newlen);
+/** Return a newly allocated socks5_server_method with all elements
+ * set to zero.
+ */
+socks5_server_method_t *socks5_server_method_new(void);
+/** Release all storage held by the socks5_server_method in 'victim'.
+ * (Do nothing if 'victim' is NULL.)
+ */
+void socks5_server_method_free(socks5_server_method_t *victim);
+/** Try to parse a socks5_server_method from the buffer in 'input',
+ * using up to 'len_in' bytes from the input buffer. On success,
+ * return the number of bytes consumed and set *output to the newly
+ * allocated socks5_server_method_t. On failure, return -2 if the
+ * input appears truncated, and -1 if the input is otherwise invalid.
+ */
+ssize_t socks5_server_method_parse(socks5_server_method_t **output, const uint8_t *input, const size_t len_in);
+/** Return the number of bytes we expect to need to encode the
+ * socks5_server_method in 'obj'. On failure, return a negative value.
+ * Note that this value may be an overestimate, and can even be an
+ * underestimate for certain unencodeable objects.
+ */
+ssize_t socks5_server_method_encoded_len(const socks5_server_method_t *obj);
+/** Try to encode the socks5_server_method from 'input' into the
+ * buffer at 'output', using up to 'avail' bytes of the output buffer.
+ * On success, return the number of bytes used. On failure, return -2
+ * if the buffer was not long enough, and -1 if the input was invalid.
+ */
+ssize_t socks5_server_method_encode(uint8_t *output, size_t avail, const socks5_server_method_t *input);
+/** Check whether the internal state of the socks5_server_method in
+ * 'obj' is consistent. Return NULL if it is, and a short message if
+ * it is not.
+ */
+const char *socks5_server_method_check(const socks5_server_method_t *obj);
+/** Clear any errors that were set on the object 'obj' by its setter
+ * functions. Return true iff errors were cleared.
+ */
+int socks5_server_method_clear_errors(socks5_server_method_t *obj);
+/** Return the value of the version field of the
+ * socks5_server_method_t in 'inp'
+ */
+uint8_t socks5_server_method_get_version(const socks5_server_method_t *inp);
+/** Set the value of the version field of the socks5_server_method_t
+ * in 'inp' to 'val'. Return 0 on success; return -1 and set the error
+ * code on 'inp' on failure.
+ */
+int socks5_server_method_set_version(socks5_server_method_t *inp, uint8_t val);
+/** Return the value of the method field of the socks5_server_method_t
+ * in 'inp'
+ */
+uint8_t socks5_server_method_get_method(const socks5_server_method_t *inp);
+/** Set the value of the method field of the socks5_server_method_t in
+ * 'inp' to 'val'. Return 0 on success; return -1 and set the error
+ * code on 'inp' on failure.
+ */
+int socks5_server_method_set_method(socks5_server_method_t *inp, uint8_t val);
+/** Return a newly allocated socks5_server_userpass_auth with all
+ * elements set to zero.
+ */
+socks5_server_userpass_auth_t *socks5_server_userpass_auth_new(void);
+/** Release all storage held by the socks5_server_userpass_auth in
+ * 'victim'. (Do nothing if 'victim' is NULL.)
+ */
+void socks5_server_userpass_auth_free(socks5_server_userpass_auth_t *victim);
+/** Try to parse a socks5_server_userpass_auth from the buffer in
+ * 'input', using up to 'len_in' bytes from the input buffer. On
+ * success, return the number of bytes consumed and set *output to the
+ * newly allocated socks5_server_userpass_auth_t. On failure, return
+ * -2 if the input appears truncated, and -1 if the input is otherwise
+ * invalid.
+ */
+ssize_t socks5_server_userpass_auth_parse(socks5_server_userpass_auth_t **output, const uint8_t *input, const size_t len_in);
+/** Return the number of bytes we expect to need to encode the
+ * socks5_server_userpass_auth in 'obj'. On failure, return a negative
+ * value. Note that this value may be an overestimate, and can even be
+ * an underestimate for certain unencodeable objects.
+ */
+ssize_t socks5_server_userpass_auth_encoded_len(const socks5_server_userpass_auth_t *obj);
+/** Try to encode the socks5_server_userpass_auth from 'input' into
+ * the buffer at 'output', using up to 'avail' bytes of the output
+ * buffer. On success, return the number of bytes used. On failure,
+ * return -2 if the buffer was not long enough, and -1 if the input
+ * was invalid.
+ */
+ssize_t socks5_server_userpass_auth_encode(uint8_t *output, size_t avail, const socks5_server_userpass_auth_t *input);
+/** Check whether the internal state of the
+ * socks5_server_userpass_auth in 'obj' is consistent. Return NULL if
+ * it is, and a short message if it is not.
+ */
+const char *socks5_server_userpass_auth_check(const socks5_server_userpass_auth_t *obj);
+/** Clear any errors that were set on the object 'obj' by its setter
+ * functions. Return true iff errors were cleared.
+ */
+int socks5_server_userpass_auth_clear_errors(socks5_server_userpass_auth_t *obj);
+/** Return the value of the version field of the
+ * socks5_server_userpass_auth_t in 'inp'
+ */
+uint8_t socks5_server_userpass_auth_get_version(const socks5_server_userpass_auth_t *inp);
+/** Set the value of the version field of the
+ * socks5_server_userpass_auth_t in 'inp' to 'val'. Return 0 on
+ * success; return -1 and set the error code on 'inp' on failure.
+ */
+int socks5_server_userpass_auth_set_version(socks5_server_userpass_auth_t *inp, uint8_t val);
+/** Return the value of the status field of the
+ * socks5_server_userpass_auth_t in 'inp'
+ */
+uint8_t socks5_server_userpass_auth_get_status(const socks5_server_userpass_auth_t *inp);
+/** Set the value of the status field of the
+ * socks5_server_userpass_auth_t in 'inp' to 'val'. Return 0 on
+ * success; return -1 and set the error code on 'inp' on failure.
+ */
+int socks5_server_userpass_auth_set_status(socks5_server_userpass_auth_t *inp, uint8_t val);
+/** Return a newly allocated socks5_client_request with all elements
+ * set to zero.
+ */
+socks5_client_request_t *socks5_client_request_new(void);
+/** Release all storage held by the socks5_client_request in 'victim'.
+ * (Do nothing if 'victim' is NULL.)
+ */
+void socks5_client_request_free(socks5_client_request_t *victim);
+/** Try to parse a socks5_client_request from the buffer in 'input',
+ * using up to 'len_in' bytes from the input buffer. On success,
+ * return the number of bytes consumed and set *output to the newly
+ * allocated socks5_client_request_t. On failure, return -2 if the
+ * input appears truncated, and -1 if the input is otherwise invalid.
+ */
+ssize_t socks5_client_request_parse(socks5_client_request_t **output, const uint8_t *input, const size_t len_in);
+/** Return the number of bytes we expect to need to encode the
+ * socks5_client_request in 'obj'. On failure, return a negative
+ * value. Note that this value may be an overestimate, and can even be
+ * an underestimate for certain unencodeable objects.
+ */
+ssize_t socks5_client_request_encoded_len(const socks5_client_request_t *obj);
+/** Try to encode the socks5_client_request from 'input' into the
+ * buffer at 'output', using up to 'avail' bytes of the output buffer.
+ * On success, return the number of bytes used. On failure, return -2
+ * if the buffer was not long enough, and -1 if the input was invalid.
+ */
+ssize_t socks5_client_request_encode(uint8_t *output, size_t avail, const socks5_client_request_t *input);
+/** Check whether the internal state of the socks5_client_request in
+ * 'obj' is consistent. Return NULL if it is, and a short message if
+ * it is not.
+ */
+const char *socks5_client_request_check(const socks5_client_request_t *obj);
+/** Clear any errors that were set on the object 'obj' by its setter
+ * functions. Return true iff errors were cleared.
+ */
+int socks5_client_request_clear_errors(socks5_client_request_t *obj);
+/** Return the value of the version field of the
+ * socks5_client_request_t in 'inp'
+ */
+uint8_t socks5_client_request_get_version(const socks5_client_request_t *inp);
+/** Set the value of the version field of the socks5_client_request_t
+ * in 'inp' to 'val'. Return 0 on success; return -1 and set the error
+ * code on 'inp' on failure.
+ */
+int socks5_client_request_set_version(socks5_client_request_t *inp, uint8_t val);
+/** Return the value of the command field of the
+ * socks5_client_request_t in 'inp'
+ */
+uint8_t socks5_client_request_get_command(const socks5_client_request_t *inp);
+/** Set the value of the command field of the socks5_client_request_t
+ * in 'inp' to 'val'. Return 0 on success; return -1 and set the error
+ * code on 'inp' on failure.
+ */
+int socks5_client_request_set_command(socks5_client_request_t *inp, uint8_t val);
+/** Return the value of the reserved field of the
+ * socks5_client_request_t in 'inp'
+ */
+uint8_t socks5_client_request_get_reserved(const socks5_client_request_t *inp);
+/** Set the value of the reserved field of the socks5_client_request_t
+ * in 'inp' to 'val'. Return 0 on success; return -1 and set the error
+ * code on 'inp' on failure.
+ */
+int socks5_client_request_set_reserved(socks5_client_request_t *inp, uint8_t val);
+/** Return the value of the atype field of the socks5_client_request_t
+ * in 'inp'
+ */
+uint8_t socks5_client_request_get_atype(const socks5_client_request_t *inp);
+/** Set the value of the atype field of the socks5_client_request_t in
+ * 'inp' to 'val'. Return 0 on success; return -1 and set the error
+ * code on 'inp' on failure.
+ */
+int socks5_client_request_set_atype(socks5_client_request_t *inp, uint8_t val);
+/** Return the value of the dest_addr_ipv4 field of the
+ * socks5_client_request_t in 'inp'
+ */
+uint32_t socks5_client_request_get_dest_addr_ipv4(const socks5_client_request_t *inp);
+/** Set the value of the dest_addr_ipv4 field of the
+ * socks5_client_request_t in 'inp' to 'val'. Return 0 on success;
+ * return -1 and set the error code on 'inp' on failure.
+ */
+int socks5_client_request_set_dest_addr_ipv4(socks5_client_request_t *inp, uint32_t val);
+/** Return the (constant) length of the array holding the
+ * dest_addr_ipv6 field of the socks5_client_request_t in 'inp'.
+ */
+size_t socks5_client_request_getlen_dest_addr_ipv6(const socks5_client_request_t *inp);
+/** Return the element at position 'idx' of the fixed array field
+ * dest_addr_ipv6 of the socks5_client_request_t in 'inp'.
+ */
+uint8_t socks5_client_request_get_dest_addr_ipv6(socks5_client_request_t *inp, size_t idx);
+/** As socks5_client_request_get_dest_addr_ipv6, but take and return a
+ * const pointer
+ */
+uint8_t socks5_client_request_getconst_dest_addr_ipv6(const socks5_client_request_t *inp, size_t idx);
+/** Change the element at position 'idx' of the fixed array field
+ * dest_addr_ipv6 of the socks5_client_request_t in 'inp', so that it
+ * will hold the value 'elt'.
+ */
+int socks5_client_request_set_dest_addr_ipv6(socks5_client_request_t *inp, size_t idx, uint8_t elt);
+/** Return a pointer to the 16-element array field dest_addr_ipv6 of
+ * 'inp'.
+ */
+uint8_t * socks5_client_request_getarray_dest_addr_ipv6(socks5_client_request_t *inp);
+/** As socks5_client_request_get_dest_addr_ipv6, but take and return a
+ * const pointer
+ */
+const uint8_t  * socks5_client_request_getconstarray_dest_addr_ipv6(const socks5_client_request_t *inp);
+/** Return the value of the dest_addr_domainname field of the
+ * socks5_client_request_t in 'inp'
+ */
+struct domainname_st * socks5_client_request_get_dest_addr_domainname(socks5_client_request_t *inp);
+/** As socks5_client_request_get_dest_addr_domainname, but take and
+ * return a const pointer
+ */
+const struct domainname_st * socks5_client_request_getconst_dest_addr_domainname(const socks5_client_request_t *inp);
+/** Set the value of the dest_addr_domainname field of the
+ * socks5_client_request_t in 'inp' to 'val'. Free the old value if
+ * any. Steals the referenceto 'val'.Return 0 on success; return -1
+ * and set the error code on 'inp' on failure.
+ */
+int socks5_client_request_set_dest_addr_domainname(socks5_client_request_t *inp, struct domainname_st *val);
+/** As socks5_client_request_set_dest_addr_domainname, but does not
+ * free the previous value.
+ */
+int socks5_client_request_set0_dest_addr_domainname(socks5_client_request_t *inp, struct domainname_st *val);
+/** Return the value of the dest_port field of the
+ * socks5_client_request_t in 'inp'
+ */
+uint16_t socks5_client_request_get_dest_port(const socks5_client_request_t *inp);
+/** Set the value of the dest_port field of the
+ * socks5_client_request_t in 'inp' to 'val'. Return 0 on success;
+ * return -1 and set the error code on 'inp' on failure.
+ */
+int socks5_client_request_set_dest_port(socks5_client_request_t *inp, uint16_t val);
+/** Return a newly allocated socks5_server_reply with all elements set
+ * to zero.
+ */
+socks5_server_reply_t *socks5_server_reply_new(void);
+/** Release all storage held by the socks5_server_reply in 'victim'.
+ * (Do nothing if 'victim' is NULL.)
+ */
+void socks5_server_reply_free(socks5_server_reply_t *victim);
+/** Try to parse a socks5_server_reply from the buffer in 'input',
+ * using up to 'len_in' bytes from the input buffer. On success,
+ * return the number of bytes consumed and set *output to the newly
+ * allocated socks5_server_reply_t. On failure, return -2 if the input
+ * appears truncated, and -1 if the input is otherwise invalid.
+ */
+ssize_t socks5_server_reply_parse(socks5_server_reply_t **output, const uint8_t *input, const size_t len_in);
+/** Return the number of bytes we expect to need to encode the
+ * socks5_server_reply in 'obj'. On failure, return a negative value.
+ * Note that this value may be an overestimate, and can even be an
+ * underestimate for certain unencodeable objects.
+ */
+ssize_t socks5_server_reply_encoded_len(const socks5_server_reply_t *obj);
+/** Try to encode the socks5_server_reply from 'input' into the buffer
+ * at 'output', using up to 'avail' bytes of the output buffer. On
+ * success, return the number of bytes used. On failure, return -2 if
+ * the buffer was not long enough, and -1 if the input was invalid.
+ */
+ssize_t socks5_server_reply_encode(uint8_t *output, size_t avail, const socks5_server_reply_t *input);
+/** Check whether the internal state of the socks5_server_reply in
+ * 'obj' is consistent. Return NULL if it is, and a short message if
+ * it is not.
+ */
+const char *socks5_server_reply_check(const socks5_server_reply_t *obj);
+/** Clear any errors that were set on the object 'obj' by its setter
+ * functions. Return true iff errors were cleared.
+ */
+int socks5_server_reply_clear_errors(socks5_server_reply_t *obj);
+/** Return the value of the version field of the socks5_server_reply_t
+ * in 'inp'
+ */
+uint8_t socks5_server_reply_get_version(const socks5_server_reply_t *inp);
+/** Set the value of the version field of the socks5_server_reply_t in
+ * 'inp' to 'val'. Return 0 on success; return -1 and set the error
+ * code on 'inp' on failure.
+ */
+int socks5_server_reply_set_version(socks5_server_reply_t *inp, uint8_t val);
+/** Return the value of the reply field of the socks5_server_reply_t
+ * in 'inp'
+ */
+uint8_t socks5_server_reply_get_reply(const socks5_server_reply_t *inp);
+/** Set the value of the reply field of the socks5_server_reply_t in
+ * 'inp' to 'val'. Return 0 on success; return -1 and set the error
+ * code on 'inp' on failure.
+ */
+int socks5_server_reply_set_reply(socks5_server_reply_t *inp, uint8_t val);
+/** Return the value of the reserved field of the
+ * socks5_server_reply_t in 'inp'
+ */
+uint8_t socks5_server_reply_get_reserved(const socks5_server_reply_t *inp);
+/** Set the value of the reserved field of the socks5_server_reply_t
+ * in 'inp' to 'val'. Return 0 on success; return -1 and set the error
+ * code on 'inp' on failure.
+ */
+int socks5_server_reply_set_reserved(socks5_server_reply_t *inp, uint8_t val);
+/** Return the value of the atype field of the socks5_server_reply_t
+ * in 'inp'
+ */
+uint8_t socks5_server_reply_get_atype(const socks5_server_reply_t *inp);
+/** Set the value of the atype field of the socks5_server_reply_t in
+ * 'inp' to 'val'. Return 0 on success; return -1 and set the error
+ * code on 'inp' on failure.
+ */
+int socks5_server_reply_set_atype(socks5_server_reply_t *inp, uint8_t val);
+/** Return the value of the bind_addr_ipv4 field of the
+ * socks5_server_reply_t in 'inp'
+ */
+uint32_t socks5_server_reply_get_bind_addr_ipv4(const socks5_server_reply_t *inp);
+/** Set the value of the bind_addr_ipv4 field of the
+ * socks5_server_reply_t in 'inp' to 'val'. Return 0 on success;
+ * return -1 and set the error code on 'inp' on failure.
+ */
+int socks5_server_reply_set_bind_addr_ipv4(socks5_server_reply_t *inp, uint32_t val);
+/** Return the (constant) length of the array holding the
+ * bind_addr_ipv6 field of the socks5_server_reply_t in 'inp'.
+ */
+size_t socks5_server_reply_getlen_bind_addr_ipv6(const socks5_server_reply_t *inp);
+/** Return the element at position 'idx' of the fixed array field
+ * bind_addr_ipv6 of the socks5_server_reply_t in 'inp'.
+ */
+uint8_t socks5_server_reply_get_bind_addr_ipv6(socks5_server_reply_t *inp, size_t idx);
+/** As socks5_server_reply_get_bind_addr_ipv6, but take and return a
+ * const pointer
+ */
+uint8_t socks5_server_reply_getconst_bind_addr_ipv6(const socks5_server_reply_t *inp, size_t idx);
+/** Change the element at position 'idx' of the fixed array field
+ * bind_addr_ipv6 of the socks5_server_reply_t in 'inp', so that it
+ * will hold the value 'elt'.
+ */
+int socks5_server_reply_set_bind_addr_ipv6(socks5_server_reply_t *inp, size_t idx, uint8_t elt);
+/** Return a pointer to the 16-element array field bind_addr_ipv6 of
+ * 'inp'.
+ */
+uint8_t * socks5_server_reply_getarray_bind_addr_ipv6(socks5_server_reply_t *inp);
+/** As socks5_server_reply_get_bind_addr_ipv6, but take and return a
+ * const pointer
+ */
+const uint8_t  * socks5_server_reply_getconstarray_bind_addr_ipv6(const socks5_server_reply_t *inp);
+/** Return the value of the bind_addr_domainname field of the
+ * socks5_server_reply_t in 'inp'
+ */
+struct domainname_st * socks5_server_reply_get_bind_addr_domainname(socks5_server_reply_t *inp);
+/** As socks5_server_reply_get_bind_addr_domainname, but take and
+ * return a const pointer
+ */
+const struct domainname_st * socks5_server_reply_getconst_bind_addr_domainname(const socks5_server_reply_t *inp);
+/** Set the value of the bind_addr_domainname field of the
+ * socks5_server_reply_t in 'inp' to 'val'. Free the old value if any.
+ * Steals the referenceto 'val'.Return 0 on success; return -1 and set
+ * the error code on 'inp' on failure.
+ */
+int socks5_server_reply_set_bind_addr_domainname(socks5_server_reply_t *inp, struct domainname_st *val);
+/** As socks5_server_reply_set_bind_addr_domainname, but does not free
+ * the previous value.
+ */
+int socks5_server_reply_set0_bind_addr_domainname(socks5_server_reply_t *inp, struct domainname_st *val);
+/** Return the value of the bind_port field of the
+ * socks5_server_reply_t in 'inp'
+ */
+uint16_t socks5_server_reply_get_bind_port(const socks5_server_reply_t *inp);
+/** Set the value of the bind_port field of the socks5_server_reply_t
+ * in 'inp' to 'val'. Return 0 on success; return -1 and set the error
+ * code on 'inp' on failure.
+ */
+int socks5_server_reply_set_bind_port(socks5_server_reply_t *inp, uint16_t val);
+
+
+#endif

src/trunnel/socks5.trunnel

@@ -0,0 +1,94 @@
+// Example: here's a quickie implementation of the messages in the
+// socks5 protocol.
+
+struct socks5_client_version {
+   u8 version IN [5];
+   u8 n_methods;
+   u8 methods[n_methods];
+}
+
+struct socks5_server_method {
+   u8 version IN [5];
+   u8 method;
+}
+
+const CMD_CONNECT = 1;
+const CMD_BIND = 2;
+const CMD_UDP_ASSOCIATE = 3;
+// This is a tor extension
+const CMD_RESOLVE = 0xF0;
+const CMD_RESOLVE_PTR = 0xF1;
+
+const ATYPE_IPV4 = 1;
+const ATYPE_IPV6 = 4;
+const ATYPE_DOMAINNAME = 3;
+
+struct domainname {
+   u8 len;
+   char name[len];
+}
+
+struct socks5_client_request {
+   u8 version IN [5];
+   u8 command IN [CMD_CONNECT, CMD_BIND, CMD_UDP_ASSOCIATE, CMD_RESOLVE, CMD_RESOLVE_PTR];
+   u8 reserved IN [0];
+   u8 atype;
+   union dest_addr[atype] {
+     ATYPE_IPV4: u32 ipv4;
+     ATYPE_IPV6: u8 ipv6[16];
+     ATYPE_DOMAINNAME: struct domainname domainname;
+     default: fail;
+   };
+   u16 dest_port;
+}
+
+struct socks5_server_reply {
+   u8 version IN [5];
+   u8 reply;
+   u8 reserved IN [0];
+   u8 atype;
+   union bind_addr[atype] {
+     ATYPE_IPV4: u32 ipv4;
+     ATYPE_IPV6: u8 ipv6[16];
+     ATYPE_DOMAINNAME: struct domainname domainname;
+     default: fail;
+   };
+   u16 bind_port;
+}
+
+struct socks5_client_userpass_auth {
+   u8 version IN [1];
+   u8 username_len;
+   char username[username_len];
+   u8 passwd_len;
+   char passwd[passwd_len];
+}
+
+struct socks5_server_userpass_auth {
+   u8 version IN [1];
+   u8 status;
+}
+
+// Oh why not.  Here's socks4 and socks4a.
+
+struct socks4_client_request {
+   u8 version IN [4];
+   u8 command IN [CMD_CONNECT,CMD_BIND,CMD_RESOLVE,CMD_RESOLVE_PTR];
+   u16 port;
+   u32 addr;
+   nulterm username;
+   union socks4a_addr[addr] {
+      1..255:
+               nulterm hostname;
+      default:
+               ;
+   };
+}
+
+struct socks4_server_reply {
+   u8 version IN [4];
+   u8 status;
+   u16 port;
+   u32 addr;
+}
+