| /* Copyright (c) 2016, Google Inc. |
| * |
| * Permission to use, copy, modify, and/or distribute this software for any |
| * purpose with or without fee is hereby granted, provided that the above |
| * copyright notice and this permission notice appear in all copies. |
| * |
| * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES |
| * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF |
| * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY |
| * SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES |
| * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN ACTION |
| * OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF OR IN |
| * CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE. */ |
| |
| #include <openssl/ssl.h> |
| |
| #include <assert.h> |
| #include <limits.h> |
| #include <string.h> |
| |
| #include <utility> |
| |
| #include <openssl/bytestring.h> |
| #include <openssl/digest.h> |
| #include <openssl/err.h> |
| #include <openssl/mem.h> |
| #include <openssl/sha.h> |
| #include <openssl/stack.h> |
| |
| #include "../crypto/internal.h" |
| #include "internal.h" |
| |
| |
| BSSL_NAMESPACE_BEGIN |
| |
| enum client_hs_state_t { |
| state_read_hello_retry_request = 0, |
| state_send_second_client_hello, |
| state_read_server_hello, |
| state_read_encrypted_extensions, |
| state_read_certificate_request, |
| state_read_server_certificate, |
| state_read_server_certificate_verify, |
| state_server_certificate_reverify, |
| state_read_server_finished, |
| state_send_end_of_early_data, |
| state_send_client_encrypted_extensions, |
| state_send_client_certificate, |
| state_send_client_certificate_verify, |
| state_complete_second_flight, |
| state_done, |
| }; |
| |
| static const uint8_t kZeroes[EVP_MAX_MD_SIZE] = {0}; |
| |
| // end_of_early_data closes the early data stream for |hs| and switches the |
| // encryption level to |level|. It returns true on success and false on error. |
| static bool close_early_data(SSL_HANDSHAKE *hs, ssl_encryption_level_t level) { |
| SSL *const ssl = hs->ssl; |
| assert(hs->in_early_data); |
| |
| // Note |can_early_write| may already be false if |SSL_write| exceeded the |
| // early data write limit. |
| hs->can_early_write = false; |
| |
| // 0-RTT write states on the client differ between TLS 1.3, DTLS 1.3, and |
| // QUIC. TLS 1.3 has one write encryption level at a time. 0-RTT write keys |
| // overwrite the null cipher and defer handshake write keys. While a |
| // HelloRetryRequest can cause us to rewind back to the null cipher, sequence |
| // numbers have no effect, so we can install a "new" null cipher. |
| // |
| // In QUIC and DTLS 1.3, 0-RTT write state cannot override or defer the normal |
| // write state. The two ClientHello sequence numbers must align, and handshake |
| // write keys must be installed early to ACK the EncryptedExtensions. |
| // |
| // We do not currently implement DTLS 1.3 and, in QUIC, the caller handles |
| // 0-RTT data, so we can skip installing 0-RTT keys and act as if there is one |
| // write level. If we implement DTLS 1.3, we'll need to model this better. |
| if (ssl->quic_method == nullptr) { |
| if (level == ssl_encryption_initial) { |
| bssl::UniquePtr<SSLAEADContext> null_ctx = |
| SSLAEADContext::CreateNullCipher(SSL_is_dtls(ssl)); |
| if (!null_ctx || |
| !ssl->method->set_write_state(ssl, ssl_encryption_initial, |
| std::move(null_ctx), |
| /*secret_for_quic=*/{})) { |
| return false; |
| } |
| ssl->s3->aead_write_ctx->SetVersionIfNullCipher(ssl->version); |
| } else { |
| assert(level == ssl_encryption_handshake); |
| if (!tls13_set_traffic_key(ssl, ssl_encryption_handshake, evp_aead_seal, |
| hs->new_session.get(), |
| hs->client_handshake_secret())) { |
| return false; |
| } |
| } |
| } |
| |
| assert(ssl->s3->write_level == level); |
| return true; |
| } |
| |
| static enum ssl_hs_wait_t do_read_hello_retry_request(SSL_HANDSHAKE *hs) { |
| SSL *const ssl = hs->ssl; |
| assert(ssl->s3->have_version); |
| SSLMessage msg; |
| if (!ssl->method->get_message(ssl, &msg)) { |
| return ssl_hs_read_message; |
| } |
| |
| // Queue up a ChangeCipherSpec for whenever we next send something. This |
| // will be before the second ClientHello. If we offered early data, this was |
| // already done. |
| if (!hs->early_data_offered && |
| !ssl->method->add_change_cipher_spec(ssl)) { |
| return ssl_hs_error; |
| } |
| |
| if (!ssl_check_message_type(ssl, msg, SSL3_MT_SERVER_HELLO)) { |
| return ssl_hs_error; |
| } |
| |
| CBS body = msg.body, extensions, server_random, session_id; |
| uint16_t server_version, cipher_suite; |
| uint8_t compression_method; |
| if (!CBS_get_u16(&body, &server_version) || |
| !CBS_get_bytes(&body, &server_random, SSL3_RANDOM_SIZE) || |
| !CBS_get_u8_length_prefixed(&body, &session_id) || |
| !CBS_mem_equal(&session_id, hs->session_id, hs->session_id_len) || |
| !CBS_get_u16(&body, &cipher_suite) || |
| !CBS_get_u8(&body, &compression_method) || |
| compression_method != 0 || |
| !CBS_get_u16_length_prefixed(&body, &extensions) || |
| CBS_len(&extensions) == 0 || |
| CBS_len(&body) != 0) { |
| OPENSSL_PUT_ERROR(SSL, SSL_R_DECODE_ERROR); |
| ssl_send_alert(ssl, SSL3_AL_FATAL, SSL_AD_DECODE_ERROR); |
| return ssl_hs_error; |
| } |
| |
| if (!CBS_mem_equal(&server_random, kHelloRetryRequest, SSL3_RANDOM_SIZE)) { |
| hs->tls13_state = state_read_server_hello; |
| return ssl_hs_ok; |
| } |
| |
| const SSL_CIPHER *cipher = SSL_get_cipher_by_value(cipher_suite); |
| // Check if the cipher is a TLS 1.3 cipher. |
| if (cipher == NULL || |
| SSL_CIPHER_get_min_version(cipher) > ssl_protocol_version(ssl) || |
| SSL_CIPHER_get_max_version(cipher) < ssl_protocol_version(ssl)) { |
| OPENSSL_PUT_ERROR(SSL, SSL_R_WRONG_CIPHER_RETURNED); |
| ssl_send_alert(ssl, SSL3_AL_FATAL, SSL_AD_ILLEGAL_PARAMETER); |
| return ssl_hs_error; |
| } |
| |
| hs->new_cipher = cipher; |
| |
| if (!hs->transcript.InitHash(ssl_protocol_version(ssl), hs->new_cipher) || |
| !hs->transcript.UpdateForHelloRetryRequest()) { |
| return ssl_hs_error; |
| } |
| |
| |
| bool have_cookie, have_key_share, have_supported_versions; |
| CBS cookie, key_share, supported_versions; |
| SSL_EXTENSION_TYPE ext_types[] = { |
| {TLSEXT_TYPE_key_share, &have_key_share, &key_share}, |
| {TLSEXT_TYPE_cookie, &have_cookie, &cookie}, |
| {TLSEXT_TYPE_supported_versions, &have_supported_versions, |
| &supported_versions}, |
| }; |
| |
| uint8_t alert = SSL_AD_DECODE_ERROR; |
| if (!ssl_parse_extensions(&extensions, &alert, ext_types, |
| /*ignore_unknown=*/false)) { |
| ssl_send_alert(ssl, SSL3_AL_FATAL, alert); |
| return ssl_hs_error; |
| } |
| |
| if (!have_cookie && !have_key_share) { |
| OPENSSL_PUT_ERROR(SSL, SSL_R_EMPTY_HELLO_RETRY_REQUEST); |
| ssl_send_alert(ssl, SSL3_AL_FATAL, SSL_AD_ILLEGAL_PARAMETER); |
| return ssl_hs_error; |
| } |
| if (have_cookie) { |
| CBS cookie_value; |
| if (!CBS_get_u16_length_prefixed(&cookie, &cookie_value) || |
| CBS_len(&cookie_value) == 0 || |
| CBS_len(&cookie) != 0) { |
| OPENSSL_PUT_ERROR(SSL, SSL_R_DECODE_ERROR); |
| ssl_send_alert(ssl, SSL3_AL_FATAL, SSL_AD_DECODE_ERROR); |
| return ssl_hs_error; |
| } |
| |
| if (!hs->cookie.CopyFrom(cookie_value)) { |
| return ssl_hs_error; |
| } |
| } |
| |
| if (have_key_share) { |
| uint16_t group_id; |
| if (!CBS_get_u16(&key_share, &group_id) || CBS_len(&key_share) != 0) { |
| OPENSSL_PUT_ERROR(SSL, SSL_R_DECODE_ERROR); |
| ssl_send_alert(ssl, SSL3_AL_FATAL, SSL_AD_DECODE_ERROR); |
| return ssl_hs_error; |
| } |
| |
| // The group must be supported. |
| if (!tls1_check_group_id(hs, group_id)) { |
| ssl_send_alert(ssl, SSL3_AL_FATAL, SSL_AD_ILLEGAL_PARAMETER); |
| OPENSSL_PUT_ERROR(SSL, SSL_R_WRONG_CURVE); |
| return ssl_hs_error; |
| } |
| |
| // Check that the HelloRetryRequest does not request a key share that was |
| // provided in the initial ClientHello. |
| if (hs->key_shares[0]->GroupID() == group_id || |
| (hs->key_shares[1] && hs->key_shares[1]->GroupID() == group_id)) { |
| ssl_send_alert(ssl, SSL3_AL_FATAL, SSL_AD_ILLEGAL_PARAMETER); |
| OPENSSL_PUT_ERROR(SSL, SSL_R_WRONG_CURVE); |
| return ssl_hs_error; |
| } |
| |
| hs->key_shares[0].reset(); |
| hs->key_shares[1].reset(); |
| hs->retry_group = group_id; |
| } |
| |
| if (!ssl_hash_message(hs, msg)) { |
| return ssl_hs_error; |
| } |
| |
| // HelloRetryRequest should be the end of the flight. |
| if (ssl->method->has_unprocessed_handshake_data(ssl)) { |
| ssl_send_alert(ssl, SSL3_AL_FATAL, SSL_AD_UNEXPECTED_MESSAGE); |
| OPENSSL_PUT_ERROR(SSL, SSL_R_EXCESS_HANDSHAKE_DATA); |
| return ssl_hs_error; |
| } |
| |
| ssl->method->next_message(ssl); |
| ssl->s3->used_hello_retry_request = true; |
| hs->tls13_state = state_send_second_client_hello; |
| // 0-RTT is rejected if we receive a HelloRetryRequest. |
| if (hs->in_early_data) { |
| ssl->s3->early_data_reason = ssl_early_data_hello_retry_request; |
| if (!close_early_data(hs, ssl_encryption_initial)) { |
| return ssl_hs_error; |
| } |
| return ssl_hs_early_data_rejected; |
| } |
| return ssl_hs_ok; |
| } |
| |
| static enum ssl_hs_wait_t do_send_second_client_hello(SSL_HANDSHAKE *hs) { |
| // Any 0-RTT keys must have been discarded. |
| assert(hs->ssl->s3->write_level == ssl_encryption_initial); |
| |
| if (!ssl_write_client_hello(hs)) { |
| return ssl_hs_error; |
| } |
| |
| hs->tls13_state = state_read_server_hello; |
| return ssl_hs_flush; |
| } |
| |
| static enum ssl_hs_wait_t do_read_server_hello(SSL_HANDSHAKE *hs) { |
| SSL *const ssl = hs->ssl; |
| SSLMessage msg; |
| if (!ssl->method->get_message(ssl, &msg)) { |
| return ssl_hs_read_message; |
| } |
| if (!ssl_check_message_type(ssl, msg, SSL3_MT_SERVER_HELLO)) { |
| return ssl_hs_error; |
| } |
| |
| CBS body = msg.body, server_random, session_id, extensions; |
| uint16_t server_version; |
| uint16_t cipher_suite; |
| uint8_t compression_method; |
| if (!CBS_get_u16(&body, &server_version) || |
| !CBS_get_bytes(&body, &server_random, SSL3_RANDOM_SIZE) || |
| !CBS_get_u8_length_prefixed(&body, &session_id) || |
| !CBS_mem_equal(&session_id, hs->session_id, hs->session_id_len) || |
| !CBS_get_u16(&body, &cipher_suite) || |
| !CBS_get_u8(&body, &compression_method) || |
| compression_method != 0 || |
| !CBS_get_u16_length_prefixed(&body, &extensions) || |
| CBS_len(&body) != 0) { |
| ssl_send_alert(ssl, SSL3_AL_FATAL, SSL_AD_DECODE_ERROR); |
| OPENSSL_PUT_ERROR(SSL, SSL_R_DECODE_ERROR); |
| return ssl_hs_error; |
| } |
| |
| if (server_version != TLS1_2_VERSION) { |
| ssl_send_alert(ssl, SSL3_AL_FATAL, SSL_AD_DECODE_ERROR); |
| OPENSSL_PUT_ERROR(SSL, SSL_R_WRONG_VERSION_NUMBER); |
| return ssl_hs_error; |
| } |
| |
| // Forbid a second HelloRetryRequest. |
| if (CBS_mem_equal(&server_random, kHelloRetryRequest, SSL3_RANDOM_SIZE)) { |
| ssl_send_alert(ssl, SSL3_AL_FATAL, SSL_AD_UNEXPECTED_MESSAGE); |
| OPENSSL_PUT_ERROR(SSL, SSL_R_UNEXPECTED_MESSAGE); |
| return ssl_hs_error; |
| } |
| |
| OPENSSL_memcpy(ssl->s3->server_random, CBS_data(&server_random), |
| SSL3_RANDOM_SIZE); |
| |
| // Check if the cipher is a TLS 1.3 cipher. |
| const SSL_CIPHER *cipher = SSL_get_cipher_by_value(cipher_suite); |
| if (cipher == nullptr || |
| SSL_CIPHER_get_min_version(cipher) > ssl_protocol_version(ssl) || |
| SSL_CIPHER_get_max_version(cipher) < ssl_protocol_version(ssl)) { |
| OPENSSL_PUT_ERROR(SSL, SSL_R_WRONG_CIPHER_RETURNED); |
| ssl_send_alert(ssl, SSL3_AL_FATAL, SSL_AD_ILLEGAL_PARAMETER); |
| return ssl_hs_error; |
| } |
| |
| // Check that the cipher matches the one in the HelloRetryRequest. |
| if (ssl->s3->used_hello_retry_request && hs->new_cipher != cipher) { |
| OPENSSL_PUT_ERROR(SSL, SSL_R_WRONG_CIPHER_RETURNED); |
| ssl_send_alert(ssl, SSL3_AL_FATAL, SSL_AD_ILLEGAL_PARAMETER); |
| return ssl_hs_error; |
| } |
| |
| // Parse out the extensions. |
| bool have_key_share = false, have_pre_shared_key = false, |
| have_supported_versions = false; |
| CBS key_share, pre_shared_key, supported_versions; |
| SSL_EXTENSION_TYPE ext_types[] = { |
| {TLSEXT_TYPE_key_share, &have_key_share, &key_share}, |
| {TLSEXT_TYPE_pre_shared_key, &have_pre_shared_key, &pre_shared_key}, |
| {TLSEXT_TYPE_supported_versions, &have_supported_versions, |
| &supported_versions}, |
| }; |
| |
| uint8_t alert = SSL_AD_DECODE_ERROR; |
| if (!ssl_parse_extensions(&extensions, &alert, ext_types, |
| /*ignore_unknown=*/false)) { |
| ssl_send_alert(ssl, SSL3_AL_FATAL, alert); |
| return ssl_hs_error; |
| } |
| |
| // Recheck supported_versions, in case this is the second ServerHello. |
| uint16_t version; |
| if (!have_supported_versions || |
| !CBS_get_u16(&supported_versions, &version) || |
| version != ssl->version) { |
| OPENSSL_PUT_ERROR(SSL, SSL_R_SECOND_SERVERHELLO_VERSION_MISMATCH); |
| ssl_send_alert(ssl, SSL3_AL_FATAL, SSL_AD_ILLEGAL_PARAMETER); |
| return ssl_hs_error; |
| } |
| |
| alert = SSL_AD_DECODE_ERROR; |
| if (have_pre_shared_key) { |
| if (ssl->session == NULL) { |
| OPENSSL_PUT_ERROR(SSL, SSL_R_UNEXPECTED_EXTENSION); |
| ssl_send_alert(ssl, SSL3_AL_FATAL, SSL_AD_UNSUPPORTED_EXTENSION); |
| return ssl_hs_error; |
| } |
| |
| if (!ssl_ext_pre_shared_key_parse_serverhello(hs, &alert, |
| &pre_shared_key)) { |
| ssl_send_alert(ssl, SSL3_AL_FATAL, alert); |
| return ssl_hs_error; |
| } |
| |
| if (ssl->session->ssl_version != ssl->version) { |
| OPENSSL_PUT_ERROR(SSL, SSL_R_OLD_SESSION_VERSION_NOT_RETURNED); |
| ssl_send_alert(ssl, SSL3_AL_FATAL, SSL_AD_ILLEGAL_PARAMETER); |
| return ssl_hs_error; |
| } |
| |
| if (ssl->session->cipher->algorithm_prf != cipher->algorithm_prf) { |
| OPENSSL_PUT_ERROR(SSL, SSL_R_OLD_SESSION_PRF_HASH_MISMATCH); |
| ssl_send_alert(ssl, SSL3_AL_FATAL, SSL_AD_ILLEGAL_PARAMETER); |
| return ssl_hs_error; |
| } |
| |
| if (!ssl_session_is_context_valid(hs, ssl->session.get())) { |
| // This is actually a client application bug. |
| OPENSSL_PUT_ERROR(SSL, |
| SSL_R_ATTEMPT_TO_REUSE_SESSION_IN_DIFFERENT_CONTEXT); |
| ssl_send_alert(ssl, SSL3_AL_FATAL, SSL_AD_ILLEGAL_PARAMETER); |
| return ssl_hs_error; |
| } |
| |
| ssl->s3->session_reused = true; |
| // Only authentication information carries over in TLS 1.3. |
| hs->new_session = |
| SSL_SESSION_dup(ssl->session.get(), SSL_SESSION_DUP_AUTH_ONLY); |
| if (!hs->new_session) { |
| ssl_send_alert(ssl, SSL3_AL_FATAL, SSL_AD_INTERNAL_ERROR); |
| return ssl_hs_error; |
| } |
| ssl_set_session(ssl, NULL); |
| |
| // Resumption incorporates fresh key material, so refresh the timeout. |
| ssl_session_renew_timeout(ssl, hs->new_session.get(), |
| ssl->session_ctx->session_psk_dhe_timeout); |
| } else if (!ssl_get_new_session(hs, 0)) { |
| ssl_send_alert(ssl, SSL3_AL_FATAL, SSL_AD_INTERNAL_ERROR); |
| return ssl_hs_error; |
| } |
| |
| hs->new_session->cipher = cipher; |
| hs->new_cipher = cipher; |
| |
| size_t hash_len = |
| EVP_MD_size(ssl_get_handshake_digest(ssl_protocol_version(ssl), cipher)); |
| |
| // Set up the key schedule and incorporate the PSK into the running secret. |
| if (ssl->s3->session_reused) { |
| if (!tls13_init_key_schedule( |
| hs, MakeConstSpan(hs->new_session->secret, |
| hs->new_session->secret_length))) { |
| return ssl_hs_error; |
| } |
| } else if (!tls13_init_key_schedule(hs, MakeConstSpan(kZeroes, hash_len))) { |
| return ssl_hs_error; |
| } |
| |
| if (!have_key_share) { |
| // We do not support psk_ke and thus always require a key share. |
| OPENSSL_PUT_ERROR(SSL, SSL_R_MISSING_KEY_SHARE); |
| ssl_send_alert(ssl, SSL3_AL_FATAL, SSL_AD_MISSING_EXTENSION); |
| return ssl_hs_error; |
| } |
| |
| // Resolve ECDHE and incorporate it into the secret. |
| Array<uint8_t> dhe_secret; |
| alert = SSL_AD_DECODE_ERROR; |
| if (!ssl_ext_key_share_parse_serverhello(hs, &dhe_secret, &alert, |
| &key_share)) { |
| ssl_send_alert(ssl, SSL3_AL_FATAL, alert); |
| return ssl_hs_error; |
| } |
| |
| if (!tls13_advance_key_schedule(hs, dhe_secret) || |
| !ssl_hash_message(hs, msg) || |
| !tls13_derive_handshake_secrets(hs)) { |
| return ssl_hs_error; |
| } |
| |
| // If currently sending early data over TCP, we defer installing client |
| // traffic keys to when the early data stream is closed. See |
| // |close_early_data|. Note if the server has already rejected 0-RTT via |
| // HelloRetryRequest, |in_early_data| is already false. |
| if (!hs->in_early_data || ssl->quic_method != nullptr) { |
| if (!tls13_set_traffic_key(ssl, ssl_encryption_handshake, evp_aead_seal, |
| hs->new_session.get(), |
| hs->client_handshake_secret())) { |
| return ssl_hs_error; |
| } |
| } |
| |
| if (!tls13_set_traffic_key(ssl, ssl_encryption_handshake, evp_aead_open, |
| hs->new_session.get(), |
| hs->server_handshake_secret())) { |
| return ssl_hs_error; |
| } |
| |
| ssl->method->next_message(ssl); |
| hs->tls13_state = state_read_encrypted_extensions; |
| return ssl_hs_ok; |
| } |
| |
| static enum ssl_hs_wait_t do_read_encrypted_extensions(SSL_HANDSHAKE *hs) { |
| SSL *const ssl = hs->ssl; |
| SSLMessage msg; |
| if (!ssl->method->get_message(ssl, &msg)) { |
| return ssl_hs_read_message; |
| } |
| if (!ssl_check_message_type(ssl, msg, SSL3_MT_ENCRYPTED_EXTENSIONS)) { |
| return ssl_hs_error; |
| } |
| |
| CBS body = msg.body; |
| if (!ssl_parse_serverhello_tlsext(hs, &body)) { |
| OPENSSL_PUT_ERROR(SSL, SSL_R_PARSE_TLSEXT); |
| return ssl_hs_error; |
| } |
| if (CBS_len(&body) != 0) { |
| OPENSSL_PUT_ERROR(SSL, SSL_R_DECODE_ERROR); |
| ssl_send_alert(ssl, SSL3_AL_FATAL, SSL_AD_DECODE_ERROR); |
| return ssl_hs_error; |
| } |
| |
| if (ssl->s3->early_data_accepted) { |
| if (hs->early_session->cipher != hs->new_session->cipher) { |
| OPENSSL_PUT_ERROR(SSL, SSL_R_CIPHER_MISMATCH_ON_EARLY_DATA); |
| ssl_send_alert(ssl, SSL3_AL_FATAL, SSL_AD_ILLEGAL_PARAMETER); |
| return ssl_hs_error; |
| } |
| if (MakeConstSpan(hs->early_session->early_alpn) != |
| ssl->s3->alpn_selected) { |
| OPENSSL_PUT_ERROR(SSL, SSL_R_ALPN_MISMATCH_ON_EARLY_DATA); |
| ssl_send_alert(ssl, SSL3_AL_FATAL, SSL_AD_ILLEGAL_PARAMETER); |
| return ssl_hs_error; |
| } |
| // Channel ID and Token Binding are incompatible with 0-RTT. The ALPS |
| // extension should be negotiated implicitly. |
| if (ssl->s3->channel_id_valid || ssl->s3->token_binding_negotiated || |
| hs->new_session->has_application_settings) { |
| OPENSSL_PUT_ERROR(SSL, SSL_R_UNEXPECTED_EXTENSION_ON_EARLY_DATA); |
| ssl_send_alert(ssl, SSL3_AL_FATAL, SSL_AD_ILLEGAL_PARAMETER); |
| return ssl_hs_error; |
| } |
| hs->new_session->has_application_settings = |
| hs->early_session->has_application_settings; |
| if (!hs->new_session->local_application_settings.CopyFrom( |
| hs->early_session->local_application_settings) || |
| !hs->new_session->peer_application_settings.CopyFrom( |
| hs->early_session->peer_application_settings)) { |
| ssl_send_alert(ssl, SSL3_AL_FATAL, SSL_AD_INTERNAL_ERROR); |
| return ssl_hs_error; |
| } |
| } |
| |
| // Store the negotiated ALPN in the session. |
| if (!hs->new_session->early_alpn.CopyFrom(ssl->s3->alpn_selected)) { |
| ssl_send_alert(ssl, SSL3_AL_FATAL, SSL_AD_INTERNAL_ERROR); |
| return ssl_hs_error; |
| } |
| |
| if (!ssl_hash_message(hs, msg)) { |
| return ssl_hs_error; |
| } |
| |
| ssl->method->next_message(ssl); |
| hs->tls13_state = state_read_certificate_request; |
| if (hs->in_early_data && !ssl->s3->early_data_accepted) { |
| if (!close_early_data(hs, ssl_encryption_handshake)) { |
| return ssl_hs_error; |
| } |
| return ssl_hs_early_data_rejected; |
| } |
| return ssl_hs_ok; |
| } |
| |
| static enum ssl_hs_wait_t do_read_certificate_request(SSL_HANDSHAKE *hs) { |
| SSL *const ssl = hs->ssl; |
| // CertificateRequest may only be sent in non-resumption handshakes. |
| if (ssl->s3->session_reused) { |
| if (ssl->ctx->reverify_on_resume && !ssl->s3->early_data_accepted) { |
| hs->tls13_state = state_server_certificate_reverify; |
| return ssl_hs_ok; |
| } |
| hs->tls13_state = state_read_server_finished; |
| return ssl_hs_ok; |
| } |
| |
| SSLMessage msg; |
| if (!ssl->method->get_message(ssl, &msg)) { |
| return ssl_hs_read_message; |
| } |
| |
| // CertificateRequest is optional. |
| if (msg.type != SSL3_MT_CERTIFICATE_REQUEST) { |
| hs->tls13_state = state_read_server_certificate; |
| return ssl_hs_ok; |
| } |
| |
| |
| bool have_sigalgs = false, have_ca = false; |
| CBS sigalgs, ca; |
| const SSL_EXTENSION_TYPE ext_types[] = { |
| {TLSEXT_TYPE_signature_algorithms, &have_sigalgs, &sigalgs}, |
| {TLSEXT_TYPE_certificate_authorities, &have_ca, &ca}, |
| }; |
| |
| CBS body = msg.body, context, extensions, supported_signature_algorithms; |
| uint8_t alert = SSL_AD_DECODE_ERROR; |
| if (!CBS_get_u8_length_prefixed(&body, &context) || |
| // The request context is always empty during the handshake. |
| CBS_len(&context) != 0 || |
| !CBS_get_u16_length_prefixed(&body, &extensions) || |
| CBS_len(&body) != 0 || |
| !ssl_parse_extensions(&extensions, &alert, ext_types, |
| /*ignore_unknown=*/true) || |
| (have_ca && CBS_len(&ca) == 0) || |
| !have_sigalgs || |
| !CBS_get_u16_length_prefixed(&sigalgs, |
| &supported_signature_algorithms) || |
| !tls1_parse_peer_sigalgs(hs, &supported_signature_algorithms)) { |
| ssl_send_alert(ssl, SSL3_AL_FATAL, alert); |
| OPENSSL_PUT_ERROR(SSL, SSL_R_DECODE_ERROR); |
| return ssl_hs_error; |
| } |
| |
| if (have_ca) { |
| hs->ca_names = ssl_parse_client_CA_list(ssl, &alert, &ca); |
| if (!hs->ca_names) { |
| ssl_send_alert(ssl, SSL3_AL_FATAL, alert); |
| return ssl_hs_error; |
| } |
| } else { |
| hs->ca_names.reset(sk_CRYPTO_BUFFER_new_null()); |
| if (!hs->ca_names) { |
| OPENSSL_PUT_ERROR(SSL, ERR_R_MALLOC_FAILURE); |
| ssl_send_alert(ssl, SSL3_AL_FATAL, SSL_AD_INTERNAL_ERROR); |
| return ssl_hs_error; |
| } |
| } |
| |
| hs->cert_request = true; |
| ssl->ctx->x509_method->hs_flush_cached_ca_names(hs); |
| |
| if (!ssl_hash_message(hs, msg)) { |
| return ssl_hs_error; |
| } |
| |
| ssl->method->next_message(ssl); |
| hs->tls13_state = state_read_server_certificate; |
| return ssl_hs_ok; |
| } |
| |
| static enum ssl_hs_wait_t do_read_server_certificate(SSL_HANDSHAKE *hs) { |
| SSL *const ssl = hs->ssl; |
| SSLMessage msg; |
| if (!ssl->method->get_message(ssl, &msg)) { |
| return ssl_hs_read_message; |
| } |
| |
| if (msg.type != SSL3_MT_COMPRESSED_CERTIFICATE && |
| !ssl_check_message_type(ssl, msg, SSL3_MT_CERTIFICATE)) { |
| return ssl_hs_error; |
| } |
| |
| if (!tls13_process_certificate(hs, msg, false /* certificate required */) || |
| !ssl_hash_message(hs, msg)) { |
| return ssl_hs_error; |
| } |
| |
| ssl->method->next_message(ssl); |
| hs->tls13_state = state_read_server_certificate_verify; |
| return ssl_hs_ok; |
| } |
| |
| static enum ssl_hs_wait_t do_read_server_certificate_verify(SSL_HANDSHAKE *hs) { |
| SSL *const ssl = hs->ssl; |
| SSLMessage msg; |
| if (!ssl->method->get_message(ssl, &msg)) { |
| return ssl_hs_read_message; |
| } |
| switch (ssl_verify_peer_cert(hs)) { |
| case ssl_verify_ok: |
| break; |
| case ssl_verify_invalid: |
| return ssl_hs_error; |
| case ssl_verify_retry: |
| hs->tls13_state = state_read_server_certificate_verify; |
| return ssl_hs_certificate_verify; |
| } |
| |
| if (!ssl_check_message_type(ssl, msg, SSL3_MT_CERTIFICATE_VERIFY) || |
| !tls13_process_certificate_verify(hs, msg) || |
| !ssl_hash_message(hs, msg)) { |
| return ssl_hs_error; |
| } |
| |
| ssl->method->next_message(ssl); |
| hs->tls13_state = state_read_server_finished; |
| return ssl_hs_ok; |
| } |
| |
| static enum ssl_hs_wait_t do_server_certificate_reverify(SSL_HANDSHAKE *hs) { |
| switch (ssl_reverify_peer_cert(hs, /*send_alert=*/true)) { |
| case ssl_verify_ok: |
| break; |
| case ssl_verify_invalid: |
| return ssl_hs_error; |
| case ssl_verify_retry: |
| hs->tls13_state = state_server_certificate_reverify; |
| return ssl_hs_certificate_verify; |
| } |
| hs->tls13_state = state_read_server_finished; |
| return ssl_hs_ok; |
| } |
| |
| static enum ssl_hs_wait_t do_read_server_finished(SSL_HANDSHAKE *hs) { |
| SSL *const ssl = hs->ssl; |
| SSLMessage msg; |
| if (!ssl->method->get_message(ssl, &msg)) { |
| return ssl_hs_read_message; |
| } |
| if (!ssl_check_message_type(ssl, msg, SSL3_MT_FINISHED) || |
| !tls13_process_finished(hs, msg, false /* don't use saved value */) || |
| !ssl_hash_message(hs, msg) || |
| // Update the secret to the master secret and derive traffic keys. |
| !tls13_advance_key_schedule( |
| hs, MakeConstSpan(kZeroes, hs->transcript.DigestLen())) || |
| !tls13_derive_application_secrets(hs)) { |
| return ssl_hs_error; |
| } |
| |
| // Finished should be the end of the flight. |
| if (ssl->method->has_unprocessed_handshake_data(ssl)) { |
| ssl_send_alert(ssl, SSL3_AL_FATAL, SSL_AD_UNEXPECTED_MESSAGE); |
| OPENSSL_PUT_ERROR(SSL, SSL_R_EXCESS_HANDSHAKE_DATA); |
| return ssl_hs_error; |
| } |
| |
| ssl->method->next_message(ssl); |
| hs->tls13_state = state_send_end_of_early_data; |
| return ssl_hs_ok; |
| } |
| |
| static enum ssl_hs_wait_t do_send_end_of_early_data(SSL_HANDSHAKE *hs) { |
| SSL *const ssl = hs->ssl; |
| |
| if (ssl->s3->early_data_accepted) { |
| // QUIC omits the EndOfEarlyData message. See draft-ietf-quic-tls-22, |
| // section 8.3. |
| if (ssl->quic_method == nullptr) { |
| ScopedCBB cbb; |
| CBB body; |
| if (!ssl->method->init_message(ssl, cbb.get(), &body, |
| SSL3_MT_END_OF_EARLY_DATA) || |
| !ssl_add_message_cbb(ssl, cbb.get())) { |
| return ssl_hs_error; |
| } |
| } |
| |
| if (!close_early_data(hs, ssl_encryption_handshake)) { |
| return ssl_hs_error; |
| } |
| } |
| |
| hs->tls13_state = state_send_client_encrypted_extensions; |
| return ssl_hs_ok; |
| } |
| |
| static enum ssl_hs_wait_t do_send_client_encrypted_extensions( |
| SSL_HANDSHAKE *hs) { |
| SSL *const ssl = hs->ssl; |
| // For now, only one extension uses client EncryptedExtensions. This function |
| // may be generalized if others use it in the future. |
| if (hs->new_session->has_application_settings && |
| !ssl->s3->early_data_accepted) { |
| ScopedCBB cbb; |
| CBB body, extensions, extension; |
| if (!ssl->method->init_message(ssl, cbb.get(), &body, |
| SSL3_MT_ENCRYPTED_EXTENSIONS) || |
| !CBB_add_u16_length_prefixed(&body, &extensions) || |
| !CBB_add_u16(&extensions, TLSEXT_TYPE_application_settings) || |
| !CBB_add_u16_length_prefixed(&extensions, &extension) || |
| !CBB_add_bytes(&extension, |
| hs->new_session->local_application_settings.data(), |
| hs->new_session->local_application_settings.size()) || |
| !ssl_add_message_cbb(ssl, cbb.get())) { |
| return ssl_hs_error; |
| } |
| } |
| |
| hs->tls13_state = state_send_client_certificate; |
| return ssl_hs_ok; |
| } |
| |
| static enum ssl_hs_wait_t do_send_client_certificate(SSL_HANDSHAKE *hs) { |
| SSL *const ssl = hs->ssl; |
| |
| // The peer didn't request a certificate. |
| if (!hs->cert_request) { |
| hs->tls13_state = state_complete_second_flight; |
| return ssl_hs_ok; |
| } |
| |
| // Call cert_cb to update the certificate. |
| if (hs->config->cert->cert_cb != NULL) { |
| int rv = hs->config->cert->cert_cb(ssl, hs->config->cert->cert_cb_arg); |
| if (rv == 0) { |
| ssl_send_alert(ssl, SSL3_AL_FATAL, SSL_AD_INTERNAL_ERROR); |
| OPENSSL_PUT_ERROR(SSL, SSL_R_CERT_CB_ERROR); |
| return ssl_hs_error; |
| } |
| if (rv < 0) { |
| hs->tls13_state = state_send_client_certificate; |
| return ssl_hs_x509_lookup; |
| } |
| } |
| |
| if (!ssl_on_certificate_selected(hs) || |
| !tls13_add_certificate(hs)) { |
| return ssl_hs_error; |
| } |
| |
| hs->tls13_state = state_send_client_certificate_verify; |
| return ssl_hs_ok; |
| } |
| |
| static enum ssl_hs_wait_t do_send_client_certificate_verify(SSL_HANDSHAKE *hs) { |
| // Don't send CertificateVerify if there is no certificate. |
| if (!ssl_has_certificate(hs)) { |
| hs->tls13_state = state_complete_second_flight; |
| return ssl_hs_ok; |
| } |
| |
| switch (tls13_add_certificate_verify(hs)) { |
| case ssl_private_key_success: |
| hs->tls13_state = state_complete_second_flight; |
| return ssl_hs_ok; |
| |
| case ssl_private_key_retry: |
| hs->tls13_state = state_send_client_certificate_verify; |
| return ssl_hs_private_key_operation; |
| |
| case ssl_private_key_failure: |
| return ssl_hs_error; |
| } |
| |
| assert(0); |
| return ssl_hs_error; |
| } |
| |
| static enum ssl_hs_wait_t do_complete_second_flight(SSL_HANDSHAKE *hs) { |
| SSL *const ssl = hs->ssl; |
| |
| // Send a Channel ID assertion if necessary. |
| if (ssl->s3->channel_id_valid) { |
| if (!ssl_do_channel_id_callback(hs)) { |
| hs->tls13_state = state_complete_second_flight; |
| return ssl_hs_error; |
| } |
| |
| if (hs->config->channel_id_private == NULL) { |
| return ssl_hs_channel_id_lookup; |
| } |
| |
| ScopedCBB cbb; |
| CBB body; |
| if (!ssl->method->init_message(ssl, cbb.get(), &body, SSL3_MT_CHANNEL_ID) || |
| !tls1_write_channel_id(hs, &body) || |
| !ssl_add_message_cbb(ssl, cbb.get())) { |
| return ssl_hs_error; |
| } |
| } |
| |
| // Send a Finished message. |
| if (!tls13_add_finished(hs)) { |
| return ssl_hs_error; |
| } |
| |
| // Derive the final keys and enable them. |
| if (!tls13_set_traffic_key(ssl, ssl_encryption_application, evp_aead_seal, |
| hs->new_session.get(), |
| hs->client_traffic_secret_0()) || |
| !tls13_set_traffic_key(ssl, ssl_encryption_application, evp_aead_open, |
| hs->new_session.get(), |
| hs->server_traffic_secret_0()) || |
| !tls13_derive_resumption_secret(hs)) { |
| return ssl_hs_error; |
| } |
| |
| hs->tls13_state = state_done; |
| return ssl_hs_flush; |
| } |
| |
| enum ssl_hs_wait_t tls13_client_handshake(SSL_HANDSHAKE *hs) { |
| while (hs->tls13_state != state_done) { |
| enum ssl_hs_wait_t ret = ssl_hs_error; |
| enum client_hs_state_t state = |
| static_cast<enum client_hs_state_t>(hs->tls13_state); |
| switch (state) { |
| case state_read_hello_retry_request: |
| ret = do_read_hello_retry_request(hs); |
| break; |
| case state_send_second_client_hello: |
| ret = do_send_second_client_hello(hs); |
| break; |
| case state_read_server_hello: |
| ret = do_read_server_hello(hs); |
| break; |
| case state_read_encrypted_extensions: |
| ret = do_read_encrypted_extensions(hs); |
| break; |
| case state_read_certificate_request: |
| ret = do_read_certificate_request(hs); |
| break; |
| case state_read_server_certificate: |
| ret = do_read_server_certificate(hs); |
| break; |
| case state_read_server_certificate_verify: |
| ret = do_read_server_certificate_verify(hs); |
| break; |
| case state_server_certificate_reverify: |
| ret = do_server_certificate_reverify(hs); |
| break; |
| case state_read_server_finished: |
| ret = do_read_server_finished(hs); |
| break; |
| case state_send_end_of_early_data: |
| ret = do_send_end_of_early_data(hs); |
| break; |
| case state_send_client_certificate: |
| ret = do_send_client_certificate(hs); |
| break; |
| case state_send_client_encrypted_extensions: |
| ret = do_send_client_encrypted_extensions(hs); |
| break; |
| case state_send_client_certificate_verify: |
| ret = do_send_client_certificate_verify(hs); |
| break; |
| case state_complete_second_flight: |
| ret = do_complete_second_flight(hs); |
| break; |
| case state_done: |
| ret = ssl_hs_ok; |
| break; |
| } |
| |
| if (hs->tls13_state != state) { |
| ssl_do_info_callback(hs->ssl, SSL_CB_CONNECT_LOOP, 1); |
| } |
| |
| if (ret != ssl_hs_ok) { |
| return ret; |
| } |
| } |
| |
| return ssl_hs_ok; |
| } |
| |
| const char *tls13_client_handshake_state(SSL_HANDSHAKE *hs) { |
| enum client_hs_state_t state = |
| static_cast<enum client_hs_state_t>(hs->tls13_state); |
| switch (state) { |
| case state_read_hello_retry_request: |
| return "TLS 1.3 client read_hello_retry_request"; |
| case state_send_second_client_hello: |
| return "TLS 1.3 client send_second_client_hello"; |
| case state_read_server_hello: |
| return "TLS 1.3 client read_server_hello"; |
| case state_read_encrypted_extensions: |
| return "TLS 1.3 client read_encrypted_extensions"; |
| case state_read_certificate_request: |
| return "TLS 1.3 client read_certificate_request"; |
| case state_read_server_certificate: |
| return "TLS 1.3 client read_server_certificate"; |
| case state_read_server_certificate_verify: |
| return "TLS 1.3 client read_server_certificate_verify"; |
| case state_server_certificate_reverify: |
| return "TLS 1.3 client server_certificate_reverify"; |
| case state_read_server_finished: |
| return "TLS 1.3 client read_server_finished"; |
| case state_send_end_of_early_data: |
| return "TLS 1.3 client send_end_of_early_data"; |
| case state_send_client_encrypted_extensions: |
| return "TLS 1.3 client send_client_encrypted_extensions"; |
| case state_send_client_certificate: |
| return "TLS 1.3 client send_client_certificate"; |
| case state_send_client_certificate_verify: |
| return "TLS 1.3 client send_client_certificate_verify"; |
| case state_complete_second_flight: |
| return "TLS 1.3 client complete_second_flight"; |
| case state_done: |
| return "TLS 1.3 client done"; |
| } |
| |
| return "TLS 1.3 client unknown"; |
| } |
| |
| bool tls13_process_new_session_ticket(SSL *ssl, const SSLMessage &msg) { |
| if (ssl->s3->write_shutdown != ssl_shutdown_none) { |
| // Ignore tickets on shutdown. Callers tend to indiscriminately call |
| // |SSL_shutdown| before destroying an |SSL|, at which point calling the new |
| // session callback may be confusing. |
| return true; |
| } |
| |
| CBS body = msg.body; |
| UniquePtr<SSL_SESSION> session = tls13_create_session_with_ticket(ssl, &body); |
| if (!session) { |
| return false; |
| } |
| |
| if ((ssl->session_ctx->session_cache_mode & SSL_SESS_CACHE_CLIENT) && |
| ssl->session_ctx->new_session_cb != NULL && |
| ssl->session_ctx->new_session_cb(ssl, session.get())) { |
| // |new_session_cb|'s return value signals that it took ownership. |
| session.release(); |
| } |
| |
| return true; |
| } |
| |
| UniquePtr<SSL_SESSION> tls13_create_session_with_ticket(SSL *ssl, CBS *body) { |
| UniquePtr<SSL_SESSION> session = SSL_SESSION_dup( |
| ssl->s3->established_session.get(), SSL_SESSION_INCLUDE_NONAUTH); |
| if (!session) { |
| return nullptr; |
| } |
| |
| ssl_session_rebase_time(ssl, session.get()); |
| |
| uint32_t server_timeout; |
| CBS ticket_nonce, ticket, extensions; |
| if (!CBS_get_u32(body, &server_timeout) || |
| !CBS_get_u32(body, &session->ticket_age_add) || |
| !CBS_get_u8_length_prefixed(body, &ticket_nonce) || |
| !CBS_get_u16_length_prefixed(body, &ticket) || |
| !session->ticket.CopyFrom(ticket) || |
| !CBS_get_u16_length_prefixed(body, &extensions) || |
| CBS_len(body) != 0) { |
| ssl_send_alert(ssl, SSL3_AL_FATAL, SSL_AD_DECODE_ERROR); |
| OPENSSL_PUT_ERROR(SSL, SSL_R_DECODE_ERROR); |
| return nullptr; |
| } |
| |
| // Cap the renewable lifetime by the server advertised value. This avoids |
| // wasting bandwidth on 0-RTT when we know the server will reject it. |
| if (session->timeout > server_timeout) { |
| session->timeout = server_timeout; |
| } |
| |
| if (!tls13_derive_session_psk(session.get(), ticket_nonce)) { |
| return nullptr; |
| } |
| |
| // Parse out the extensions. |
| bool have_early_data = false; |
| CBS early_data; |
| const SSL_EXTENSION_TYPE ext_types[] = { |
| {TLSEXT_TYPE_early_data, &have_early_data, &early_data}, |
| }; |
| |
| uint8_t alert = SSL_AD_DECODE_ERROR; |
| if (!ssl_parse_extensions(&extensions, &alert, ext_types, |
| /*ignore_unknown=*/true)) { |
| ssl_send_alert(ssl, SSL3_AL_FATAL, alert); |
| return nullptr; |
| } |
| |
| if (have_early_data) { |
| if (!CBS_get_u32(&early_data, &session->ticket_max_early_data) || |
| CBS_len(&early_data) != 0) { |
| ssl_send_alert(ssl, SSL3_AL_FATAL, SSL_AD_DECODE_ERROR); |
| OPENSSL_PUT_ERROR(SSL, SSL_R_DECODE_ERROR); |
| return nullptr; |
| } |
| |
| // QUIC does not use the max_early_data_size parameter and always sets it to |
| // a fixed value. See draft-ietf-quic-tls-22, section 4.5. |
| if (ssl->quic_method != nullptr && |
| session->ticket_max_early_data != 0xffffffff) { |
| ssl_send_alert(ssl, SSL3_AL_FATAL, SSL_AD_ILLEGAL_PARAMETER); |
| OPENSSL_PUT_ERROR(SSL, SSL_R_DECODE_ERROR); |
| return nullptr; |
| } |
| } |
| |
| // Generate a session ID for this session. Some callers expect all sessions to |
| // have a session ID. |
| SHA256(CBS_data(&ticket), CBS_len(&ticket), session->session_id); |
| session->session_id_length = SHA256_DIGEST_LENGTH; |
| |
| session->ticket_age_add_valid = true; |
| session->not_resumable = false; |
| |
| return session; |
| } |
| |
| BSSL_NAMESPACE_END |