diff options
Diffstat (limited to 'src/common/tortls.c')
| -rw-r--r-- | src/common/tortls.c | 184 |
1 files changed, 0 insertions, 184 deletions
diff --git a/src/common/tortls.c b/src/common/tortls.c index 654efb50e4..01bccd7a53 100644 --- a/src/common/tortls.c +++ b/src/common/tortls.c @@ -217,16 +217,6 @@ struct tor_tls_t { void *callback_arg; }; -#ifdef V2_HANDSHAKE_CLIENT -/** An array of fake SSL_CIPHER objects that we use in order to trick OpenSSL - * in client mode into advertising the ciphers we want. See - * rectify_client_ciphers() for details. */ -static SSL_CIPHER *CLIENT_CIPHER_DUMMIES = NULL; -/** A stack of SSL_CIPHER objects, some real, some fake. - * See rectify_client_ciphers() for details. */ -static STACK_OF(SSL_CIPHER) *CLIENT_CIPHER_STACK = NULL; -#endif - /** The ex_data index in which we store a pointer to an SSL object's * corresponding tor_tls_t object. */ static int tor_tls_object_ex_data_index = -1; @@ -595,12 +585,6 @@ tor_tls_free_all(void) client_tls_context = NULL; tor_tls_context_decref(ctx); } -#ifdef V2_HANDSHAKE_CLIENT - if (CLIENT_CIPHER_DUMMIES) - tor_free(CLIENT_CIPHER_DUMMIES); - if (CLIENT_CIPHER_STACK) - sk_SSL_CIPHER_free(CLIENT_CIPHER_STACK); -#endif } /** We need to give OpenSSL a callback to verify certificates. This is @@ -790,7 +774,6 @@ const char UNRESTRICTED_SERVER_CIPHER_LIST[] = * (SSL3_TXT_RSA_NULL_SHA). If you do this, you won't be able to communicate * with any of the "real" Tors, though. */ -#ifdef V2_HANDSHAKE_CLIENT #define CIPHER(id, name) name ":" #define XCIPHER(id, name) /** List of ciphers that clients should advertise, omitting items that @@ -804,28 +787,6 @@ static const char CLIENT_CIPHER_LIST[] = #undef CIPHER #undef XCIPHER -/** Holds a cipher that we want to advertise, and its 2-byte ID. */ -typedef struct cipher_info_t { unsigned id; const char *name; } cipher_info_t; -/** A list of all the ciphers that clients should advertise, including items - * that OpenSSL might not know about. */ -static const cipher_info_t CLIENT_CIPHER_INFO_LIST[] = { -#define CIPHER(id, name) { id, name }, -#define XCIPHER(id, name) { id, #name }, -#include "./ciphers.inc" -#undef CIPHER -#undef XCIPHER -}; - -/** The length of CLIENT_CIPHER_INFO_LIST and CLIENT_CIPHER_DUMMIES. */ -static const int N_CLIENT_CIPHERS = ARRAY_LENGTH(CLIENT_CIPHER_INFO_LIST); -#endif - -#ifndef V2_HANDSHAKE_CLIENT -#undef CLIENT_CIPHER_LIST -#define CLIENT_CIPHER_LIST (TLS1_TXT_DHE_RSA_WITH_AES_128_SHA ":" \ - SSL3_TXT_EDH_RSA_DES_192_CBC3_SHA) -#endif - /** Free all storage held in <b>cert</b> */ void tor_cert_free(tor_cert_t *cert) @@ -1796,149 +1757,6 @@ tor_tls_setup_session_secret_cb(tor_tls_t *tls) #define tor_tls_setup_session_secret_cb(tls) STMT_NIL #endif -/** Explain which ciphers we're missing. */ -static void -log_unsupported_ciphers(smartlist_t *unsupported) -{ - char *joined; - - log_notice(LD_NET, "We weren't able to find support for all of the " - "TLS ciphersuites that we wanted to advertise. This won't " - "hurt security, but it might make your Tor (if run as a client) " - "more easy for censors to block."); - - if (SSLeay() < 0x10000000L) { - log_notice(LD_NET, "To correct this, use a more recent OpenSSL, " - "built without disabling any secure ciphers or features."); - } else { - log_notice(LD_NET, "To correct this, use a version of OpenSSL " - "built with none of its ciphers disabled."); - } - - joined = smartlist_join_strings(unsupported, ":", 0, NULL); - log_info(LD_NET, "The unsupported ciphers were: %s", joined); - tor_free(joined); -} - -static void -set_ssl_ciphers_to_list(SSL *ssl, STACK_OF(SSL_CIPHER) *stack) -{ - STACK_OF(SSL_CIPHER) *ciphers; - - int r, i; - /* #1: ensure that the ssl object has its own list of ciphers. Otherwise we - * might be about to stomp the SSL_CTX ciphers list. */ - r = SSL_set_cipher_list(ssl, "HIGH"); - tor_assert(r); - - /* #2: Grab ssl_ciphers and clear it. */ - ciphers = SSL_get_ciphers(ssl); - tor_assert(ciphers); - sk_SSL_CIPHER_zero(ciphers); - - /* #3: Copy the elements from stack. */ - for (i = 0; i < sk_SSL_CIPHER_num(stack); ++i) { - SSL_CIPHER *c = sk_SSL_CIPHER_value(stack, i); - sk_SSL_CIPHER_push(ciphers, c); - } -} - -/** Replace the ciphers on <b>ssl</b> with a new list of SSL ciphersuites: - * specifically, a list designed to mimic a common web browser. We might not - * be able to do that if OpenSSL doesn't support all the ciphers we want. - * Some of the ciphers in the list won't actually be implemented by OpenSSL: - * that's okay so long as the server doesn't select them. - * - * [If the server <b>does</b> select a bogus cipher, we won't crash or - * anything; we'll just fail later when we try to look up the cipher in - * ssl->cipher_list_by_id.] - */ -static void -rectify_client_ciphers(SSL *ssl) -{ -#ifdef V2_HANDSHAKE_CLIENT - if (PREDICT_UNLIKELY(!CLIENT_CIPHER_STACK)) { - STACK_OF(SSL_CIPHER) *ciphers = SSL_get_ciphers(ssl); - - /* We need to set CLIENT_CIPHER_STACK to an array of the ciphers - * we want to use/advertise. */ - int i = 0, j = 0; - smartlist_t *unsupported = smartlist_new(); - - /* First, create a dummy SSL_CIPHER for every cipher. */ - CLIENT_CIPHER_DUMMIES = - tor_malloc_zero(sizeof(SSL_CIPHER)*N_CLIENT_CIPHERS); - for (i=0; i < N_CLIENT_CIPHERS; ++i) { - CLIENT_CIPHER_DUMMIES[i].valid = 1; - /* The "3<<24" here signifies that the cipher is supposed to work with - * SSL3 and TLS1. */ - CLIENT_CIPHER_DUMMIES[i].id = CLIENT_CIPHER_INFO_LIST[i].id | (3<<24); - CLIENT_CIPHER_DUMMIES[i].name = CLIENT_CIPHER_INFO_LIST[i].name; - } - - CLIENT_CIPHER_STACK = sk_SSL_CIPHER_new_null(); - tor_assert(CLIENT_CIPHER_STACK); - - log_debug(LD_NET, "List was: %s", CLIENT_CIPHER_LIST); - for (j = 0; j < sk_SSL_CIPHER_num(ciphers); ++j) { - SSL_CIPHER *cipher = sk_SSL_CIPHER_value(ciphers, j); - log_debug(LD_NET, "Cipher %d: %lx %s", j, - SSL_CIPHER_get_id(cipher), SSL_CIPHER_get_name(cipher)); - } - - /* Then copy as many ciphers as we can from the good list, inserting - * dummies as needed. Let j be an index into list of ciphers we have - * (ciphers) and let i be an index into the ciphers we want - * (CLIENT_INFO_CIPHER_LIST). We are building a list of ciphers in - * CLIENT_CIPHER_STACK. - */ - for (i = j = 0; i < N_CLIENT_CIPHERS; ) { - SSL_CIPHER *cipher = NULL; - if (j < sk_SSL_CIPHER_num(ciphers)) - cipher = sk_SSL_CIPHER_value(ciphers, j); - if (cipher && ((SSL_CIPHER_get_id(cipher) >> 24) & 0xff) != 3) { - /* Skip over non-v3 ciphers entirely. (This should no longer be - * needed, thanks to saying !SSLv2 above.) */ - log_debug(LD_NET, "Skipping v%d cipher %s", - (int)((SSL_CIPHER_get_id(cipher)>>24) & 0xff), - SSL_CIPHER_get_name(cipher)); - ++j; - } else if (cipher && - (SSL_CIPHER_get_id(cipher) & 0xffff) == CLIENT_CIPHER_INFO_LIST[i].id) { - /* "cipher" is the cipher we expect. Put it on the list. */ - log_debug(LD_NET, "Found cipher %s", SSL_CIPHER_get_name(cipher)); - sk_SSL_CIPHER_push(CLIENT_CIPHER_STACK, cipher); - ++j; - ++i; - } else if (!strcmp(CLIENT_CIPHER_DUMMIES[i].name, - "SSL_RSA_FIPS_WITH_3DES_EDE_CBC_SHA")) { - /* We found bogus cipher 0xfeff, which OpenSSL doesn't support and - * never has. For this one, we need a dummy. */ - log_debug(LD_NET, "Inserting fake %s", CLIENT_CIPHER_DUMMIES[i].name); - sk_SSL_CIPHER_push(CLIENT_CIPHER_STACK, &CLIENT_CIPHER_DUMMIES[i]); - ++i; - } else { - /* OpenSSL doesn't have this one. */ - log_debug(LD_NET, "Completely omitting unsupported cipher %s", - CLIENT_CIPHER_INFO_LIST[i].name); - smartlist_add(unsupported, (char*) CLIENT_CIPHER_INFO_LIST[i].name); - ++i; - } - } - - if (smartlist_len(unsupported)) - log_unsupported_ciphers(unsupported); - - smartlist_free(unsupported); - } - - set_ssl_ciphers_to_list(ssl, CLIENT_CIPHER_STACK); - -#else - (void)ciphers; -#endif -} - /** Create a new TLS object from a file descriptor, and a flag to * determine whether it is functioning as a server. */ @@ -1978,8 +1796,6 @@ tor_tls_new(int sock, int isServer) tor_free(result); goto err; } - if (!isServer) - rectify_client_ciphers(result->ssl); result->socket = sock; bio = BIO_new_socket(sock, BIO_NOCLOSE); if (! bio) { |