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- /* Copyright 2003 Roger Dingledine. */
- /* See LICENSE for licensing information */
- /* $Id$ */
- /**
- * \file tortls.c
- *
- * \brief TLS wrappers for Tor.
- **/
- /* (Unlike other tor functions, these
- * are prefixed with tor_ in order to avoid conflicting with OpenSSL
- * functions and variables.)
- */
- #include "./crypto.h"
- #include "./tortls.h"
- #include "./util.h"
- #include "./log.h"
- #include <string.h>
- /* Copied from or.h */
- #define LEGAL_NICKNAME_CHARACTERS "abcdefghijklmnopqrstuvwxyzABCDEFGHIJKLMNOPQRSTUVWXYZ0123456789"
- #include <assert.h>
- #include <openssl/ssl.h>
- #include <openssl/err.h>
- #include <openssl/tls1.h>
- #include <openssl/asn1.h>
- #include <openssl/bio.h>
- /** How long do identity certificates live? (sec) */
- #define IDENTITY_CERT_LIFETIME (365*24*60*60)
- /** How much clock skew do we tolerate when checking certificates? (sec) */
- #define CERT_ALLOW_SKEW (90*60)
- typedef struct tor_tls_context_st {
- SSL_CTX *ctx;
- SSL_CTX *client_only_ctx;
- } tor_tls_context;
- /** Holds a SSL object and its associated data. Members are only
- * accessed from within tortls.c.
- */
- struct tor_tls_st {
- SSL *ssl; /**< An OpenSSL SSL object. */
- int socket; /**< The underlying file descriptor for this TLS connection. */
- enum {
- TOR_TLS_ST_HANDSHAKE, TOR_TLS_ST_OPEN, TOR_TLS_ST_GOTCLOSE,
- TOR_TLS_ST_SENTCLOSE, TOR_TLS_ST_CLOSED
- } state; /**< The current SSL state, depending on which operations have
- * completed successfully. */
- int isServer;
- int wantwrite_n; /**< 0 normally, >0 if we returned wantwrite last time. */
- };
- static X509* tor_tls_create_certificate(crypto_pk_env_t *rsa,
- crypto_pk_env_t *rsa_sign,
- const char *cname,
- const char *cname_sign,
- unsigned int lifetime);
- /** Global tls context. We keep it here because nobody else needs to
- * touch it. */
- static tor_tls_context *global_tls_context = NULL;
- /** True iff tor_tls_init() has been called. */
- static int tls_library_is_initialized = 0;
- /* Module-internal error codes. */
- #define _TOR_TLS_SYSCALL -6
- #define _TOR_TLS_ZERORETURN -5
- /* These functions are declared in crypto.c but not exported. */
- EVP_PKEY *_crypto_pk_env_get_evp_pkey(crypto_pk_env_t *env, int private);
- crypto_pk_env_t *_crypto_new_pk_env_rsa(RSA *rsa);
- DH *_crypto_dh_env_get_dh(crypto_dh_env_t *dh);
- /** Log all pending tls errors at level <b>severity</b>. Use
- * <b>doing</b> to describe our current activities.
- */
- static void
- tls_log_errors(int severity, const char *doing)
- {
- int err;
- const char *msg, *lib, *func;
- while ((err = ERR_get_error()) != 0) {
- msg = (const char*)ERR_reason_error_string(err);
- lib = (const char*)ERR_lib_error_string(err);
- func = (const char*)ERR_func_error_string(err);
- if (!msg) msg = "(null)";
- if (doing) {
- log(severity, "TLS error while %s: %s (in %s:%s)", doing, msg, lib,func);
- } else {
- log(severity, "TLS error: %s (in %s:%s)", msg, lib, func);
- }
- }
- }
- #define CATCH_SYSCALL 1
- #define CATCH_ZERO 2
- /** Given a TLS object and the result of an SSL_* call, use
- * SSL_get_error to determine whether an error has occurred, and if so
- * which one. Return one of TOR_TLS_{DONE|WANTREAD|WANTWRITE|ERROR}.
- * If extra&CATCH_SYSCALL is true, return _TOR_TLS_SYSCALL instead of
- * reporting syscall errors. If extra&CATCH_ZERO is true, return
- * _TOR_TLS_ZERORETURN instead of reporting zero-return errors.
- *
- * If an error has occurred, log it at level <b>severity</b> and describe the
- * current action as <b>doing</b>.
- */
- static int
- tor_tls_get_error(tor_tls *tls, int r, int extra,
- const char *doing, int severity)
- {
- int err = SSL_get_error(tls->ssl, r);
- switch (err) {
- case SSL_ERROR_NONE:
- return TOR_TLS_DONE;
- case SSL_ERROR_WANT_READ:
- return TOR_TLS_WANTREAD;
- case SSL_ERROR_WANT_WRITE:
- return TOR_TLS_WANTWRITE;
- case SSL_ERROR_SYSCALL:
- if (extra&CATCH_SYSCALL)
- return _TOR_TLS_SYSCALL;
- if (r == 0)
- log(severity, "TLS error: unexpected close while %s", doing);
- else {
- int e = tor_socket_errno(tls->socket);
- log(severity, "TLS error: <syscall error while %s> (errno=%d: %s)",
- doing, e, tor_socket_strerror(e));
- }
- tls_log_errors(severity, doing);
- return TOR_TLS_ERROR;
- case SSL_ERROR_ZERO_RETURN:
- if (extra&CATCH_ZERO)
- return _TOR_TLS_ZERORETURN;
- log(severity, "TLS error: Zero return");
- tls_log_errors(severity, doing);
- return TOR_TLS_ERROR;
- default:
- tls_log_errors(severity, doing);
- return TOR_TLS_ERROR;
- }
- }
- /** Initialize OpenSSL, unless it has already been initialized.
- */
- static void
- tor_tls_init() {
- if (!tls_library_is_initialized) {
- SSL_library_init();
- SSL_load_error_strings();
- crypto_global_init();
- OpenSSL_add_all_algorithms();
- tls_library_is_initialized = 1;
- }
- }
- /** We need to give OpenSSL a callback to verify certificates. This is
- * it: We always accept peer certs and complete the handshake. We
- * don't validate them until later.
- */
- static int always_accept_verify_cb(int preverify_ok,
- X509_STORE_CTX *x509_ctx)
- {
- return 1;
- }
- /** Generate and sign an X509 certificate with the public key <b>rsa</b>,
- * signed by the private key <b>rsa_sign</b>. The commonName of the
- * certificate will be <b>cname</b>; the commonName of the issuer will be
- * <b>cname_sign</b>. The cert will be valid for <b>cert_lifetime</b> seconds
- * starting from now. Return a certificate on success, NULL on
- * failure.
- */
- static X509 *
- tor_tls_create_certificate(crypto_pk_env_t *rsa,
- crypto_pk_env_t *rsa_sign,
- const char *cname,
- const char *cname_sign,
- unsigned int cert_lifetime)
- {
- time_t start_time, end_time;
- EVP_PKEY *sign_pkey = NULL, *pkey=NULL;
- X509 *x509 = NULL;
- X509_NAME *name = NULL, *name_issuer=NULL;
- int nid;
- tor_tls_init();
- start_time = time(NULL);
- tor_assert(rsa && cname && rsa_sign && cname_sign);
- if (!(sign_pkey = _crypto_pk_env_get_evp_pkey(rsa_sign,1)))
- goto error;
- if (!(pkey = _crypto_pk_env_get_evp_pkey(rsa,0)))
- goto error;
- if (!(x509 = X509_new()))
- goto error;
- if (!(X509_set_version(x509, 2)))
- goto error;
- if (!(ASN1_INTEGER_set(X509_get_serialNumber(x509), (long)start_time)))
- goto error;
- if (!(name = X509_NAME_new()))
- goto error;
- if ((nid = OBJ_txt2nid("organizationName")) == NID_undef) goto error;
- if (!(X509_NAME_add_entry_by_NID(name, nid, MBSTRING_ASC,
- "TOR", -1, -1, 0))) goto error;
- if ((nid = OBJ_txt2nid("commonName")) == NID_undef) goto error;
- if (!(X509_NAME_add_entry_by_NID(name, nid, MBSTRING_ASC,
- (char*)cname, -1, -1, 0))) goto error;
- if (!(X509_set_subject_name(x509, name)))
- goto error;
- if (!(name_issuer = X509_NAME_new()))
- goto error;
- if ((nid = OBJ_txt2nid("organizationName")) == NID_undef) goto error;
- if (!(X509_NAME_add_entry_by_NID(name_issuer, nid, MBSTRING_ASC,
- "TOR", -1, -1, 0))) goto error;
- if ((nid = OBJ_txt2nid("commonName")) == NID_undef) goto error;
- if (!(X509_NAME_add_entry_by_NID(name_issuer, nid, MBSTRING_ASC,
- (char*)cname_sign, -1, -1, 0))) goto error;
- if (!(X509_set_issuer_name(x509, name_issuer)))
- goto error;
- if (!X509_time_adj(X509_get_notBefore(x509),0,&start_time))
- goto error;
- end_time = start_time + cert_lifetime;
- if (!X509_time_adj(X509_get_notAfter(x509),0,&end_time))
- goto error;
- if (!X509_set_pubkey(x509, pkey))
- goto error;
- if (!X509_sign(x509, sign_pkey, EVP_sha1()))
- goto error;
- goto done;
- error:
- tls_log_errors(LOG_WARN, "generating certificate");
- if (x509) {
- X509_free(x509);
- x509 = NULL;
- }
- done:
- if (sign_pkey)
- EVP_PKEY_free(sign_pkey);
- if (pkey)
- EVP_PKEY_free(pkey);
- if (name)
- X509_NAME_free(name);
- if (name_issuer)
- X509_NAME_free(name_issuer);
- return x509;
- }
- #ifdef EVERYONE_HAS_AES
- /* Everybody is running OpenSSL 0.9.7 or later, so no backward compatibility
- * is needed. */
- #define CIPHER_LIST TLS1_TXT_DHE_RSA_WITH_AES_128_SHA
- #elif defined(TLS1_TXT_DHE_RSA_WITH_AES_128_SHA)
- /* Some people are running OpenSSL before 0.9.7, but we aren't.
- * We can support AES and 3DES.
- */
- #define CIPHER_LIST (TLS1_TXT_DHE_RSA_WITH_AES_128_SHA ":" \
- SSL3_TXT_EDH_RSA_DES_192_CBC3_SHA)
- #else
- /* We're running OpenSSL before 0.9.7. We only support 3DES. */
- #define CIPHER_LIST SSL3_TXT_EDH_RSA_DES_192_CBC3_SHA
- #endif
- /** Create a new TLS context. If we are going to be using it as a
- * server, it must have isServer set to true, <b>identity</b> set to the
- * identity key used to sign that certificate, and <b>nickname</b> set to
- * the server's nickname. If we're only going to be a client,
- * isServer should be false, identity should be NULL, and nickname
- * should be NULL. Return -1 if failure, else 0.
- *
- * You can call this function multiple times. Each time you call it,
- * it generates new certificates; all new connections will use
- * the new SSL context.
- */
- int
- tor_tls_context_new(crypto_pk_env_t *identity,
- int isServer, const char *nickname,
- unsigned int key_lifetime)
- {
- crypto_pk_env_t *rsa = NULL;
- crypto_dh_env_t *dh = NULL;
- EVP_PKEY *pkey = NULL;
- tor_tls_context *result = NULL;
- X509 *cert = NULL, *idcert = NULL;
- char nn2[1024];
- int client_only;
- SSL_CTX **ctx;
- sprintf(nn2, "%s <identity>", nickname);
- tor_tls_init();
- if (isServer) {
- /* Generate short-term RSA key. */
- if (!(rsa = crypto_new_pk_env()))
- goto error;
- if (crypto_pk_generate_key(rsa)<0)
- goto error;
- /* Create certificate signed by identity key. */
- cert = tor_tls_create_certificate(rsa, identity, nickname, nn2,
- key_lifetime);
- /* Create self-signed certificate for identity key. */
- idcert = tor_tls_create_certificate(identity, identity, nn2, nn2,
- IDENTITY_CERT_LIFETIME);
- if (!cert || !idcert) {
- log(LOG_WARN, "Error creating certificate");
- goto error;
- }
- }
- result = tor_malloc(sizeof(tor_tls_context));
- result->ctx = result->client_only_ctx = NULL;
- for (client_only=0; client_only <= 1; ++client_only) {
- ctx = client_only ? &result->client_only_ctx : &result->ctx;
- #ifdef EVERYONE_HAS_AES
- /* Tell OpenSSL to only use TLS1 */
- if (!(*ctx = SSL_CTX_new(TLSv1_method())))
- goto error;
- #else
- /* Tell OpenSSL to use SSL3 or TLS1 but not SSL2. */
- if (!(*ctx = SSL_CTX_new(SSLv23_method())))
- goto error;
- SSL_CTX_set_options(*ctx, SSL_OP_NO_SSLv2);
- #endif
- if (!SSL_CTX_set_cipher_list(*ctx, CIPHER_LIST))
- goto error;
- if (!client_only) {
- if (cert && !SSL_CTX_use_certificate(*ctx,cert))
- goto error;
- if (idcert && !SSL_CTX_add_extra_chain_cert(*ctx,idcert))
- goto error;
- }
- SSL_CTX_set_session_cache_mode(*ctx, SSL_SESS_CACHE_OFF);
- if (isServer && !client_only) {
- tor_assert(rsa);
- if (!(pkey = _crypto_pk_env_get_evp_pkey(rsa,1)))
- goto error;
- if (!SSL_CTX_use_PrivateKey(*ctx, pkey))
- goto error;
- EVP_PKEY_free(pkey);
- pkey = NULL;
- if (cert) {
- if (!SSL_CTX_check_private_key(*ctx))
- goto error;
- }
- }
- dh = crypto_dh_new();
- SSL_CTX_set_tmp_dh(*ctx, _crypto_dh_env_get_dh(dh));
- crypto_dh_free(dh);
- SSL_CTX_set_verify(*ctx, SSL_VERIFY_PEER,
- always_accept_verify_cb);
- /* let us realloc bufs that we're writing from */
- SSL_CTX_set_mode(*ctx, SSL_MODE_ACCEPT_MOVING_WRITE_BUFFER);
- }
- /* Free the old context if one exists. */
- if (global_tls_context) {
- /* This is safe even if there are open connections: OpenSSL does
- * reference counting with SSL and SSL_CTX objects. */
- SSL_CTX_free(global_tls_context->ctx);
- SSL_CTX_free(global_tls_context->client_only_ctx);
- tor_free(global_tls_context);
- }
- global_tls_context = result;
- return 0;
- error:
- tls_log_errors(LOG_WARN, "creating TLS context");
- if (pkey)
- EVP_PKEY_free(pkey);
- if (rsa)
- crypto_free_pk_env(rsa);
- if (dh)
- crypto_dh_free(dh);
- if (result && result->ctx)
- SSL_CTX_free(result->ctx);
- if (result && result->client_only_ctx)
- SSL_CTX_free(result->client_only_ctx);
- if (result)
- free(result);
- if (cert)
- X509_free(cert);
- if (idcert)
- X509_free(cert);
- return -1;
- }
- /** Create a new TLS object from a file descriptor, and a flag to
- * determine whether it is functioning as a server.
- */
- tor_tls *
- tor_tls_new(int sock, int isServer, int use_no_cert)
- {
- tor_tls *result = tor_malloc(sizeof(tor_tls));
- SSL_CTX *ctx;
- tor_assert(global_tls_context); /* make sure somebody made it first */
- ctx = use_no_cert ? global_tls_context->client_only_ctx
- : global_tls_context->ctx;
- if (!(result->ssl = SSL_new(ctx)))
- return NULL;
- result->socket = sock;
- SSL_set_fd(result->ssl, sock);
- result->state = TOR_TLS_ST_HANDSHAKE;
- result->isServer = isServer;
- result->wantwrite_n = 0;
- return result;
- }
- /** Release resources associated with a TLS object. Does not close the
- * underlying file descriptor.
- */
- void
- tor_tls_free(tor_tls *tls)
- {
- SSL_free(tls->ssl);
- free(tls);
- }
- /** Underlying function for TLS reading. Reads up to <b>len</b>
- * characters from <b>tls</b> into <b>cp</b>. On success, returns the
- * number of characters read. On failure, returns TOR_TLS_ERROR,
- * TOR_TLS_CLOSE, TOR_TLS_WANTREAD, or TOR_TLS_WANTWRITE.
- */
- int
- tor_tls_read(tor_tls *tls, char *cp, int len)
- {
- int r, err;
- tor_assert(tls && tls->ssl);
- tor_assert(tls->state == TOR_TLS_ST_OPEN);
- r = SSL_read(tls->ssl, cp, len);
- if (r > 0)
- return r;
- err = tor_tls_get_error(tls, r, CATCH_ZERO, "reading", LOG_INFO);
- log_fn(LOG_DEBUG,"returned r=%d, err=%d",r,err);
- if (err == _TOR_TLS_ZERORETURN) {
- tls->state = TOR_TLS_ST_CLOSED;
- return TOR_TLS_CLOSE;
- } else {
- tor_assert(err != TOR_TLS_DONE);
- return err;
- }
- }
- /** Underlying function for TLS writing. Write up to <b>n</b>
- * characters from <b>cp</b> onto <b>tls</b>. On success, returns the
- * number of characters written. On failure, returns TOR_TLS_ERROR,
- * TOR_TLS_WANTREAD, or TOR_TLS_WANTWRITE.
- */
- int
- tor_tls_write(tor_tls *tls, char *cp, int n)
- {
- int r, err;
- tor_assert(tls && tls->ssl);
- tor_assert(tls->state == TOR_TLS_ST_OPEN);
- if (n == 0)
- return 0;
- if(tls->wantwrite_n) {
- /* if WANTWRITE last time, we must use the _same_ n as before */
- tor_assert(n >= tls->wantwrite_n);
- log_fn(LOG_DEBUG,"resuming pending-write, (%d to flush, reusing %d)",
- n, tls->wantwrite_n);
- n = tls->wantwrite_n;
- tls->wantwrite_n = 0;
- }
- r = SSL_write(tls->ssl, cp, n);
- err = tor_tls_get_error(tls, r, 0, "writing", LOG_INFO);
- if (err == TOR_TLS_DONE) {
- return r;
- }
- if (err == TOR_TLS_WANTWRITE || err == TOR_TLS_WANTREAD) {
- // log_fn(LOG_INFO,"wantwrite or wantread. remembering the number %d.",n);
- tls->wantwrite_n = n;
- }
- return err;
- }
- /** Perform initial handshake on <b>tls</b>. When finished, returns
- * TOR_TLS_DONE. On failure, returns TOR_TLS_ERROR, TOR_TLS_WANTREAD,
- * or TOR_TLS_WANTWRITE.
- */
- int
- tor_tls_handshake(tor_tls *tls)
- {
- int r;
- tor_assert(tls && tls->ssl);
- tor_assert(tls->state == TOR_TLS_ST_HANDSHAKE);
- if (tls->isServer) {
- r = SSL_accept(tls->ssl);
- } else {
- r = SSL_connect(tls->ssl);
- }
- r = tor_tls_get_error(tls,r,0, "handshaking", LOG_INFO);
- if (r == TOR_TLS_DONE) {
- tls->state = TOR_TLS_ST_OPEN;
- }
- return r;
- }
- /** Shut down an open tls connection <b>tls</b>. When finished, returns
- * TOR_TLS_DONE. On failure, returns TOR_TLS_ERROR, TOR_TLS_WANTREAD,
- * or TOR_TLS_WANTWRITE.
- */
- int
- tor_tls_shutdown(tor_tls *tls)
- {
- int r, err;
- char buf[128];
- tor_assert(tls && tls->ssl);
- while (1) {
- if (tls->state == TOR_TLS_ST_SENTCLOSE) {
- /* If we've already called shutdown once to send a close message,
- * we read until the other side has closed too.
- */
- do {
- r = SSL_read(tls->ssl, buf, 128);
- } while (r>0);
- err = tor_tls_get_error(tls, r, CATCH_ZERO, "reading to shut down",
- LOG_INFO);
- if (err == _TOR_TLS_ZERORETURN) {
- tls->state = TOR_TLS_ST_GOTCLOSE;
- /* fall through... */
- } else {
- return err;
- }
- }
- r = SSL_shutdown(tls->ssl);
- if (r == 1) {
- /* If shutdown returns 1, the connection is entirely closed. */
- tls->state = TOR_TLS_ST_CLOSED;
- return TOR_TLS_DONE;
- }
- err = tor_tls_get_error(tls, r, CATCH_SYSCALL|CATCH_ZERO, "shutting down",
- LOG_INFO);
- if (err == _TOR_TLS_SYSCALL) {
- /* The underlying TCP connection closed while we were shutting down. */
- tls->state = TOR_TLS_ST_CLOSED;
- return TOR_TLS_DONE;
- } else if (err == _TOR_TLS_ZERORETURN) {
- /* The TLS connection says that it sent a shutdown record, but
- * isn't done shutting down yet. Make sure that this hasn't
- * happened before, then go back to the start of the function
- * and try to read.
- */
- if (tls->state == TOR_TLS_ST_GOTCLOSE ||
- tls->state == TOR_TLS_ST_SENTCLOSE) {
- log(LOG_WARN,
- "TLS returned \"half-closed\" value while already half-closed");
- return TOR_TLS_ERROR;
- }
- tls->state = TOR_TLS_ST_SENTCLOSE;
- /* fall through ... */
- } else {
- return err;
- }
- } /* end loop */
- }
- /** Return true iff this TLS connection is authenticated.
- */
- int
- tor_tls_peer_has_cert(tor_tls *tls)
- {
- X509 *cert;
- if (!(cert = SSL_get_peer_certificate(tls->ssl)))
- return 0;
- X509_free(cert);
- return 1;
- }
- /** Return the nickname (if any) that the peer connected on <b>tls</b>
- * claims to have.
- */
- int
- tor_tls_get_peer_cert_nickname(tor_tls *tls, char *buf, int buflen)
- {
- X509 *cert = NULL;
- X509_NAME *name = NULL;
- int nid;
- int lenout;
- if (!(cert = SSL_get_peer_certificate(tls->ssl))) {
- log_fn(LOG_WARN, "Peer has no certificate");
- goto error;
- }
- if (!(name = X509_get_subject_name(cert))) {
- log_fn(LOG_WARN, "Peer certificate has no subject name");
- goto error;
- }
- if ((nid = OBJ_txt2nid("commonName")) == NID_undef)
- goto error;
- lenout = X509_NAME_get_text_by_NID(name, nid, buf, buflen);
- if (lenout == -1)
- goto error;
- if (((int)strspn(buf, LEGAL_NICKNAME_CHARACTERS)) < lenout) {
- log_fn(LOG_WARN, "Peer certificate nickname has illegal characters.");
- goto error;
- }
- return 0;
- error:
- if (cert)
- X509_free(cert);
- if (name)
- X509_NAME_free(name);
- return -1;
- }
- static void log_cert_lifetime(X509 *cert, const char *problem)
- {
- BIO *bio = NULL;
- BUF_MEM *buf;
- char *s1=NULL, *s2=NULL;
- char mytime[33];
- time_t now = time(NULL);
- if (problem)
- log_fn(LOG_WARN,"Certificate %s: is your system clock set incorrectly?",
- problem);
- if (!(bio = BIO_new(BIO_s_mem()))) {
- log_fn(LOG_WARN, "Couldn't allocate BIO!"); goto end;
- }
- if (!(ASN1_TIME_print(bio, X509_get_notBefore(cert)))) {
- tls_log_errors(LOG_WARN, "printing certificate lifetime");
- goto end;
- }
- BIO_get_mem_ptr(bio, &buf);
- s1 = tor_strndup(buf->data, buf->length);
- BIO_reset(bio);
- if (!(ASN1_TIME_print(bio, X509_get_notAfter(cert)))) {
- tls_log_errors(LOG_WARN, "printing certificate lifetime");
- goto end;
- }
- BIO_get_mem_ptr(bio, &buf);
- s2 = tor_strndup(buf->data, buf->length);
- strftime(mytime, 32, "%b %d %H:%M:%S %Y GMT", gmtime(&now));
- log_fn(LOG_WARN, "(certificate lifetime runs from %s through %s. Your time is %s.)",s1,s2,mytime);
- end:
- if (bio)
- BIO_free(bio);
- if (s1)
- tor_free(s1);
- if (s2)
- tor_free(s2);
- }
- /** If the provided tls connection is authenticated and has a
- * certificate that is currently valid and signed, then set
- * *<b>identity_key</b> to the identity certificate's key and return
- * 0. Else, return -1.
- */
- int
- tor_tls_verify(tor_tls *tls, crypto_pk_env_t **identity_key)
- {
- X509 *cert = NULL, *id_cert = NULL;
- STACK_OF(X509) *chain = NULL;
- EVP_PKEY *id_pkey = NULL;
- RSA *rsa;
- int num_in_chain;
- time_t now, t;
- int r = -1, i;
- *identity_key = NULL;
- if (!(cert = SSL_get_peer_certificate(tls->ssl)))
- goto done;
- if (!(chain = SSL_get_peer_cert_chain(tls->ssl)))
- goto done;
- num_in_chain = sk_X509_num(chain);
- log_fn(LOG_DEBUG,"Number of certs in chain: %d", num_in_chain);
- /* 1 means we're receiving (server-side), and it's just the id_cert.
- * 2 means we're connecting (client-side), and it's both the link
- * cert and the id_cert.
- */
- if (num_in_chain < 1) {
- log_fn(LOG_WARN,"Unexpected number of certificates in chain (%d)",
- num_in_chain);
- goto done;
- }
- for (i=0; i<num_in_chain; ++i) {
- id_cert = sk_X509_value(chain, i);
- if (X509_cmp(id_cert, cert) != 0)
- break;
- }
- if (!id_cert) {
- log_fn(LOG_WARN,"No distinct identity certificate found");
- goto done;
- }
- now = time(NULL);
- t = now + CERT_ALLOW_SKEW;
- if (X509_cmp_time(X509_get_notBefore(cert), &t) > 0) {
- log_cert_lifetime(cert, "not yet valid");
- goto done;
- }
- t = now - CERT_ALLOW_SKEW;
- if (X509_cmp_time(X509_get_notAfter(cert), &t) < 0) {
- log_cert_lifetime(cert, "already expired");
- goto done;
- }
- if (!(id_pkey = X509_get_pubkey(id_cert)) ||
- X509_verify(cert, id_pkey) <= 0) {
- log_fn(LOG_WARN,"X509_verify on cert and pkey returned <= 0");
- tls_log_errors(LOG_WARN,"verifying certificate");
- goto done;
- }
- rsa = EVP_PKEY_get1_RSA(id_pkey);
- if (!rsa)
- goto done;
- *identity_key = _crypto_new_pk_env_rsa(rsa);
- r = 0;
- done:
- if (cert)
- X509_free(cert);
- if (id_pkey)
- EVP_PKEY_free(id_pkey);
- /* This should never get invoked, but let's make sure in case OpenSSL
- * acts unexpectedly. */
- tls_log_errors(LOG_WARN, "finishing tor_tls_verify");
- return r;
- }
- /** Return the number of bytes available for reading from <b>tls</b>.
- */
- int
- tor_tls_get_pending_bytes(tor_tls *tls)
- {
- tor_assert(tls);
- #if OPENSSL_VERSION_NUMBER < 0x0090700fl
- if (tls->ssl->rstate == SSL_ST_READ_BODY)
- return 0;
- if (tls->ssl->s3->rrec.type != SSL3_RT_APPLICATION_DATA)
- return 0;
- #endif
- return SSL_pending(tls->ssl);
- }
- /** Return the number of bytes read across the underlying socket. */
- unsigned long tor_tls_get_n_bytes_read(tor_tls *tls)
- {
- tor_assert(tls);
- return BIO_number_read(SSL_get_rbio(tls->ssl));
- }
- /** Return the number of bytes written across the underlying socket. */
- unsigned long tor_tls_get_n_bytes_written(tor_tls *tls)
- {
- tor_assert(tls);
- return BIO_number_written(SSL_get_wbio(tls->ssl));
- }
- /** Implement assert_no_tls_errors: If there are any pending OpenSSL
- * errors, log an error message and assert(0). */
- void _assert_no_tls_errors(const char *fname, int line)
- {
- if (ERR_peek_error() == 0)
- return;
- log_fn(LOG_ERR, "Unhandled OpenSSL errors found at %s:%d: ",
- fname, line);
- tls_log_errors(LOG_ERR, NULL);
- tor_assert(0);
- }
- /*
- Local Variables:
- mode:c
- indent-tabs-mode:nil
- c-basic-offset:2
- End:
- */
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