prop224: Service v3 descriptor creation and logic

This commit adds the functionality for a service to build its descriptor.
Also, a global call to build all descriptors for all services is added to the
service scheduled events.

Signed-off-by: David Goulet <dgoulet@torproject.org>

src/or/circuitlist.c

@@ -1532,6 +1532,41 @@ circuit_get_next_service_intro_circ(origin_circuit_t *start)
   return NULL;
 }
 
+/** Return the first service rendezvous circuit originating from the global
+ * circuit list after <b>start</b> or at the start of the list if <b>start</b>
+ * is NULL. Return NULL if no circuit is found.
+ *
+ * A service rendezvous point circuit has a purpose of either
+ * CIRCUIT_PURPOSE_S_CONNECT_REND or CIRCUIT_PURPOSE_S_REND_JOINED. This does
+ * not return a circuit marked for close and its state must be open. */
+origin_circuit_t *
+circuit_get_next_service_rp_circ(origin_circuit_t *start)
+{
+  int idx = 0;
+  smartlist_t *lst = circuit_get_global_list();
+
+  if (start) {
+    idx = TO_CIRCUIT(start)->global_circuitlist_idx + 1;
+  }
+
+  for ( ; idx < smartlist_len(lst); ++idx) {
+    circuit_t *circ = smartlist_get(lst, idx);
+
+    /* Ignore a marked for close circuit or purpose not matching a service
+     * intro point or if the state is not open. */
+    if (circ->marked_for_close || circ->state != CIRCUIT_STATE_OPEN ||
+        (circ->purpose != CIRCUIT_PURPOSE_S_CONNECT_REND &&
+         circ->purpose != CIRCUIT_PURPOSE_S_REND_JOINED)) {
+      continue;
+    }
+    /* The purposes we are looking for are only for origin circuits so the
+     * following is valid. */
+    return TO_ORIGIN_CIRCUIT(circ);
+  }
+  /* Not found. */
+  return NULL;
+}
+
 /** Return the first circuit originating here in global_circuitlist after
  * <b>start</b> whose purpose is <b>purpose</b>, and where <b>digest</b> (if
  * set) matches the private key digest of the rend data associated with the

src/or/circuitlist.h

@@ -48,6 +48,7 @@ origin_circuit_t *circuit_get_ready_rend_circ_by_rend_data(
 origin_circuit_t *circuit_get_next_by_pk_and_purpose(origin_circuit_t *start,
                                      const uint8_t *digest, uint8_t purpose);
 origin_circuit_t *circuit_get_next_service_intro_circ(origin_circuit_t *start);
+origin_circuit_t *circuit_get_next_service_rp_circ(origin_circuit_t *start);
 origin_circuit_t *circuit_get_next_service_hsdir_circ(origin_circuit_t *start);
 origin_circuit_t *circuit_find_to_cannibalize(uint8_t purpose,
                                               extend_info_t *info, int flags);

src/or/circuituse.c

@@ -1280,11 +1280,6 @@ circuit_build_needed_circs(time_t now)
   if (router_have_consensus_path() != CONSENSUS_PATH_UNKNOWN)
     connection_ap_rescan_and_attach_pending();
 
-  /* make sure any hidden services have enough intro points
-   * HS intro point streams only require an internal circuit */
-  if (router_have_consensus_path() != CONSENSUS_PATH_UNKNOWN)
-    rend_consider_services_intro_points();
-
   circuit_expire_old_circs_as_needed(now);
 
   if (!options->DisablePredictedCircuits)

src/or/hs_descriptor.c

@@ -58,6 +58,7 @@
 #include "hs_descriptor.h"
 
 #include "or.h"
+#include "circuitbuild.h"
 #include "ed25519_cert.h" /* Trunnel interface. */
 #include "parsecommon.h"
 #include "rendcache.h"
@@ -362,6 +363,14 @@ encode_link_specifiers(const smartlist_t *specs)
       link_specifier_set_ls_len(ls, legacy_id_len);
       break;
     }
+    case LS_ED25519_ID:
+    {
+      size_t ed25519_id_len = link_specifier_getlen_un_ed25519_id(ls);
+      uint8_t *ed25519_id_array = link_specifier_getarray_un_ed25519_id(ls);
+      memcpy(ed25519_id_array, spec->u.ed25519_id, ed25519_id_len);
+      link_specifier_set_ls_len(ls, ed25519_id_len);
+      break;
+    }
     default:
       tor_assert(0);
     }
@@ -1143,6 +1152,15 @@ decode_link_specifiers(const char *encoded)
       memcpy(hs_spec->u.legacy_id, link_specifier_getarray_un_legacy_id(ls),
              sizeof(hs_spec->u.legacy_id));
       break;
+    case LS_ED25519_ID:
+      /* Both are known at compile time so let's make sure they are the same
+       * else we can copy memory out of bound. */
+      tor_assert(link_specifier_getlen_un_ed25519_id(ls) ==
+                 sizeof(hs_spec->u.ed25519_id));
+      memcpy(hs_spec->u.ed25519_id,
+             link_specifier_getconstarray_un_ed25519_id(ls),
+             sizeof(hs_spec->u.ed25519_id));
+      break;
     default:
       goto err;
     }
@@ -2398,7 +2416,7 @@ hs_desc_intro_point_free(hs_desc_intro_point_t *ip)
   }
   if (ip->link_specifiers) {
     SMARTLIST_FOREACH(ip->link_specifiers, hs_desc_link_specifier_t *,
-                      ls, tor_free(ls));
+                      ls, hs_desc_link_specifier_free(ls));
     smartlist_free(ip->link_specifiers);
   }
   tor_cert_free(ip->auth_key_cert);
@@ -2408,3 +2426,73 @@ hs_desc_intro_point_free(hs_desc_intro_point_t *ip)
   tor_free(ip);
 }
 
+/* Free the given descriptor link specifier. */
+void
+hs_desc_link_specifier_free(hs_desc_link_specifier_t *ls)
+{
+  if (ls == NULL) {
+    return;
+  }
+  tor_free(ls);
+}
+
+/* Return a newly allocated descriptor link specifier using the given extend
+ * info and requested type. Return NULL on error. */
+hs_desc_link_specifier_t *
+hs_desc_link_specifier_new(const extend_info_t *info, uint8_t type)
+{
+  hs_desc_link_specifier_t *ls = NULL;
+
+  tor_assert(info);
+
+  ls = tor_malloc_zero(sizeof(*ls));
+  ls->type = type;
+  switch (ls->type) {
+  case LS_IPV4:
+    if (info->addr.family != AF_INET) {
+      goto err;
+    }
+    tor_addr_copy(&ls->u.ap.addr, &info->addr);
+    ls->u.ap.port = info->port;
+    break;
+  case LS_IPV6:
+    if (info->addr.family != AF_INET6) {
+      goto err;
+    }
+    tor_addr_copy(&ls->u.ap.addr, &info->addr);
+    ls->u.ap.port = info->port;
+    break;
+  case LS_LEGACY_ID:
+    memcpy(ls->u.legacy_id, info->identity_digest, sizeof(ls->u.legacy_id));
+    break;
+  case LS_ED25519_ID:
+    memcpy(ls->u.ed25519_id, info->ed_identity.pubkey,
+           sizeof(ls->u.ed25519_id));
+    break;
+  default:
+    /* Unknown type is code flow error. */
+    tor_assert(0);
+  }
+
+  return ls;
+ err:
+  tor_free(ls);
+  return NULL;
+}
+
+/* From the given descriptor, remove and free every introduction point. */
+void
+hs_descriptor_free_intro_points(hs_descriptor_t *desc)
+{
+  smartlist_t *ips;
+
+  tor_assert(desc);
+
+  ips = desc->encrypted_data.intro_points;
+  if (ips) {
+    SMARTLIST_FOREACH(ips, hs_desc_intro_point_t *,
+                      ip, hs_desc_intro_point_free(ip));
+    smartlist_clear(ips);
+  }
+}
+

src/or/hs_descriptor.h

@@ -23,6 +23,9 @@
 /* The latest descriptor format version we support. */
 #define HS_DESC_SUPPORTED_FORMAT_VERSION_MAX 3
 
+/* Default lifetime of a descriptor in seconds. The valus is set at 3 hours
+ * which is 180 minutes or 10800 seconds. */
+#define HS_DESC_DEFAULT_LIFETIME (3 * 60 * 60)
 /* Maximum lifetime of a descriptor in seconds. The value is set at 12 hours
  * which is 720 minutes or 43200 seconds. */
 #define HS_DESC_MAX_LIFETIME (12 * 60 * 60)
@@ -65,12 +68,14 @@ typedef struct hs_desc_link_specifier_t {
    * specification. */
   uint8_t type;
 
-  /* It's either an address/port or a legacy identity fingerprint. */
+  /* It must be one of these types, can't be more than one. */
   union {
     /* IP address and port of the relay use to extend. */
     tor_addr_port_t ap;
     /* Legacy identity. A 20-byte SHA1 identity fingerprint. */
     uint8_t legacy_id[DIGEST_LEN];
+    /* ed25519 identity. A 32-byte key. */
+    uint8_t ed25519_id[ED25519_PUBKEY_LEN];
   } u;
 } hs_desc_link_specifier_t;
 
@@ -201,6 +206,11 @@ void hs_descriptor_free(hs_descriptor_t *desc);
 void hs_desc_plaintext_data_free(hs_desc_plaintext_data_t *desc);
 void hs_desc_encrypted_data_free(hs_desc_encrypted_data_t *desc);
 
+void hs_desc_link_specifier_free(hs_desc_link_specifier_t *ls);
+hs_desc_link_specifier_t *hs_desc_link_specifier_new(
+                                  const extend_info_t *info, uint8_t type);
+void hs_descriptor_free_intro_points(hs_descriptor_t *desc);
+
 int hs_desc_encode_descriptor(const hs_descriptor_t *desc,
                               const ed25519_keypair_t *signing_kp,
                               char **encoded_out);

src/or/hs_intropoint.c

@@ -24,6 +24,7 @@
 #include "hs/cell_introduce1.h"
 
 #include "hs_circuitmap.h"
+#include "hs_descriptor.h"
 #include "hs_intropoint.h"
 #include "hs_common.h"
 
@@ -594,3 +595,16 @@ hs_intro_received_introduce1(or_circuit_t *circ, const uint8_t *request,
   return -1;
 }
 
+/* Free the given intropoint object ip. */
+void
+hs_intro_free_content(hs_intropoint_t *ip)
+{
+  if (ip == NULL) {
+    return;
+  }
+  tor_cert_free(ip->auth_key_cert);
+  SMARTLIST_FOREACH(ip->link_specifiers, hs_desc_link_specifier_t *, ls,
+                    hs_desc_link_specifier_free(ls));
+  smartlist_free(ip->link_specifiers);
+}
+

src/or/hs_intropoint.h

@@ -13,11 +13,11 @@
 #include "torcert.h"
 
 /* Authentication key type in an ESTABLISH_INTRO cell. */
-enum hs_intro_auth_key_type {
+typedef enum {
   HS_INTRO_AUTH_KEY_TYPE_LEGACY0 = 0x00,
   HS_INTRO_AUTH_KEY_TYPE_LEGACY1 = 0x01,
   HS_INTRO_AUTH_KEY_TYPE_ED25519 = 0x02,
-};
+} hs_intro_auth_key_type_t;
 
 /* INTRODUCE_ACK status code. */
 typedef enum {
@@ -30,6 +30,9 @@ typedef enum {
 /* Object containing introduction point common data between the service and
  * the client side. */
 typedef struct hs_intropoint_t {
+  /* Does this intro point only supports legacy ID ?. */
+  unsigned int is_only_legacy : 1;
+
   /* Authentication key certificate from the descriptor. */
   tor_cert_t *auth_key_cert;
   /* A list of link specifier. */
@@ -47,6 +50,9 @@ MOCK_DECL(int, hs_intro_send_intro_established_cell,(or_circuit_t *circ));
 /* also used by rendservice.c */
 int hs_intro_circuit_is_suitable_for_establish_intro(const or_circuit_t *circ);
 
+hs_intropoint_t *hs_intro_new(void);
+void hs_intro_free_content(hs_intropoint_t *ip);
+
 #ifdef HS_INTROPOINT_PRIVATE
 
 #include "hs/cell_establish_intro.h"

src/or/hs_service.h

@@ -38,8 +38,12 @@ typedef struct hs_service_intro_point_t {
    * which is published in the descriptor. */
   ed25519_keypair_t auth_key_kp;
 
-  /* Encryption private key. */
-  curve25519_secret_key_t enc_key_sk;
+  /* Encryption keypair for the "ntor" type. */
+  curve25519_keypair_t enc_key_kp;
+
+  /* Legacy key if that intro point doesn't support v3. This should be used if
+   * the base object legacy flag is set. */
+  crypto_pk_t *legacy_key;
 
   /* Amount of INTRODUCE2 cell accepted from this intro point. */
   uint64_t introduce2_count;

src/or/rendservice.c

@@ -3983,10 +3983,9 @@ rend_max_intro_circs_per_period(unsigned int n_intro_points_wanted)
  * This is called once a second by the main loop.
  */
 void
-rend_consider_services_intro_points(void)
+rend_consider_services_intro_points(time_t now)
 {
   int i;
-  time_t now;
   const or_options_t *options = get_options();
   /* Are we in single onion mode? */
   const int allow_direct = rend_service_allow_non_anonymous_connection(
@@ -4003,7 +4002,6 @@ rend_consider_services_intro_points(void)
 
   exclude_nodes = smartlist_new();
   retry_nodes = smartlist_new();
-  now = time(NULL);
 
   SMARTLIST_FOREACH_BEGIN(rend_service_list, rend_service_t *, service) {
     int r;

src/or/rendservice.h

@@ -149,7 +149,7 @@ void rend_service_free_staging_list(void);
 int rend_service_load_all_keys(const smartlist_t *service_list);
 void rend_services_add_filenames_to_lists(smartlist_t *open_lst,
                                           smartlist_t *stat_lst);
-void rend_consider_services_intro_points(void);
+void rend_consider_services_intro_points(time_t now);
 void rend_consider_services_upload(time_t now);
 void rend_hsdir_routers_changed(void);
 void rend_consider_descriptor_republication(void);