| /* 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 <string.h> | |
| #include <tuple> | |
| #include <openssl/aead.h> | |
| #include <openssl/bytestring.h> | |
| #include <openssl/digest.h> | |
| #include <openssl/err.h> | |
| #include <openssl/hpke.h> | |
| #include <openssl/mem.h> | |
| #include <openssl/rand.h> | |
| #include <openssl/stack.h> | |
| #include "../crypto/internal.h" | |
| #include "internal.h" | |
| BSSL_NAMESPACE_BEGIN | |
| static const uint8_t kZeroes[EVP_MAX_MD_SIZE] = {0}; | |
| // Allow a minute of ticket age skew in either direction. This covers | |
| // transmission delays in ClientHello and NewSessionTicket, as well as | |
| // drift between client and server clock rate since the ticket was issued. | |
| // See RFC 8446, section 8.3. | |
| static const int32_t kMaxTicketAgeSkewSeconds = 60; | |
| static bool resolve_ecdhe_secret(SSL_HANDSHAKE *hs, | |
| const SSL_CLIENT_HELLO *client_hello) { | |
| SSL *const ssl = hs->ssl; | |
| const uint16_t group_id = hs->new_session->group_id; | |
| bool found_key_share; | |
| Span<const uint8_t> peer_key; | |
| uint8_t alert = SSL_AD_DECODE_ERROR; | |
| if (!ssl_ext_key_share_parse_clienthello(hs, &found_key_share, &peer_key, | |
| &alert, client_hello)) { | |
| ssl_send_alert(ssl, SSL3_AL_FATAL, alert); | |
| return false; | |
| } | |
| if (!found_key_share) { | |
| ssl_send_alert(ssl, SSL3_AL_FATAL, SSL_AD_ILLEGAL_PARAMETER); | |
| OPENSSL_PUT_ERROR(SSL, SSL_R_WRONG_CURVE); | |
| return false; | |
| } | |
| Array<uint8_t> secret; | |
| SSL_HANDSHAKE_HINTS *const hints = hs->hints.get(); | |
| if (hints && !hs->hints_requested && hints->key_share_group_id == group_id && | |
| !hints->key_share_secret.empty()) { | |
| // Copy DH secret from hints. | |
| if (!hs->ecdh_public_key.CopyFrom(hints->key_share_public_key) || | |
| !secret.CopyFrom(hints->key_share_secret)) { | |
| ssl_send_alert(ssl, SSL3_AL_FATAL, SSL_AD_INTERNAL_ERROR); | |
| return false; | |
| } | |
| } else { | |
| ScopedCBB public_key; | |
| UniquePtr<SSLKeyShare> key_share = SSLKeyShare::Create(group_id); | |
| if (!key_share || // | |
| !CBB_init(public_key.get(), 32) || | |
| !key_share->Accept(public_key.get(), &secret, &alert, peer_key) || | |
| !CBBFinishArray(public_key.get(), &hs->ecdh_public_key)) { | |
| ssl_send_alert(ssl, SSL3_AL_FATAL, alert); | |
| return false; | |
| } | |
| if (hints && hs->hints_requested) { | |
| hints->key_share_group_id = group_id; | |
| if (!hints->key_share_public_key.CopyFrom(hs->ecdh_public_key) || | |
| !hints->key_share_secret.CopyFrom(secret)) { | |
| ssl_send_alert(ssl, SSL3_AL_FATAL, SSL_AD_INTERNAL_ERROR); | |
| return false; | |
| } | |
| } | |
| } | |
| return tls13_advance_key_schedule(hs, secret); | |
| } | |
| static int ssl_ext_supported_versions_add_serverhello(SSL_HANDSHAKE *hs, | |
| CBB *out) { | |
| CBB contents; | |
| if (!CBB_add_u16(out, TLSEXT_TYPE_supported_versions) || | |
| !CBB_add_u16_length_prefixed(out, &contents) || | |
| !CBB_add_u16(&contents, hs->ssl->version) || | |
| !CBB_flush(out)) { | |
| return 0; | |
| } | |
| return 1; | |
| } | |
| static const SSL_CIPHER *choose_tls13_cipher( | |
| const SSL *ssl, const SSL_CLIENT_HELLO *client_hello, uint16_t group_id) { | |
| CBS cipher_suites; | |
| CBS_init(&cipher_suites, client_hello->cipher_suites, | |
| client_hello->cipher_suites_len); | |
| const uint16_t version = ssl_protocol_version(ssl); | |
| return ssl_choose_tls13_cipher(cipher_suites, version, group_id); | |
| } | |
| static bool add_new_session_tickets(SSL_HANDSHAKE *hs, bool *out_sent_tickets) { | |
| SSL *const ssl = hs->ssl; | |
| if (// If the client doesn't accept resumption with PSK_DHE_KE, don't send a | |
| // session ticket. | |
| !hs->accept_psk_mode || | |
| // We only implement stateless resumption in TLS 1.3, so skip sending | |
| // tickets if disabled. | |
| (SSL_get_options(ssl) & SSL_OP_NO_TICKET)) { | |
| *out_sent_tickets = false; | |
| return true; | |
| } | |
| // TLS 1.3 recommends single-use tickets, so issue multiple tickets in case | |
| // the client makes several connections before getting a renewal. | |
| static const int kNumTickets = 2; | |
| // Rebase the session timestamp so that it is measured from ticket | |
| // issuance. | |
| ssl_session_rebase_time(ssl, hs->new_session.get()); | |
| for (int i = 0; i < kNumTickets; i++) { | |
| UniquePtr<SSL_SESSION> session( | |
| SSL_SESSION_dup(hs->new_session.get(), SSL_SESSION_INCLUDE_NONAUTH)); | |
| if (!session) { | |
| return false; | |
| } | |
| if (!RAND_bytes((uint8_t *)&session->ticket_age_add, 4)) { | |
| return false; | |
| } | |
| session->ticket_age_add_valid = true; | |
| bool enable_early_data = | |
| ssl->enable_early_data && | |
| (!ssl->quic_method || !ssl->config->quic_early_data_context.empty()); | |
| if (enable_early_data) { | |
| // QUIC does not use the max_early_data_size parameter and always sets it | |
| // to a fixed value. See RFC 9001, section 4.6.1. | |
| session->ticket_max_early_data = | |
| ssl->quic_method != nullptr ? 0xffffffff : kMaxEarlyDataAccepted; | |
| } | |
| static_assert(kNumTickets < 256, "Too many tickets"); | |
| uint8_t nonce[] = {static_cast<uint8_t>(i)}; | |
| ScopedCBB cbb; | |
| CBB body, nonce_cbb, ticket, extensions; | |
| if (!ssl->method->init_message(ssl, cbb.get(), &body, | |
| SSL3_MT_NEW_SESSION_TICKET) || | |
| !CBB_add_u32(&body, session->timeout) || | |
| !CBB_add_u32(&body, session->ticket_age_add) || | |
| !CBB_add_u8_length_prefixed(&body, &nonce_cbb) || | |
| !CBB_add_bytes(&nonce_cbb, nonce, sizeof(nonce)) || | |
| !CBB_add_u16_length_prefixed(&body, &ticket) || | |
| !tls13_derive_session_psk(session.get(), nonce) || | |
| !ssl_encrypt_ticket(hs, &ticket, session.get()) || | |
| !CBB_add_u16_length_prefixed(&body, &extensions)) { | |
| return false; | |
| } | |
| if (enable_early_data) { | |
| CBB early_data; | |
| if (!CBB_add_u16(&extensions, TLSEXT_TYPE_early_data) || | |
| !CBB_add_u16_length_prefixed(&extensions, &early_data) || | |
| !CBB_add_u32(&early_data, session->ticket_max_early_data) || | |
| !CBB_flush(&extensions)) { | |
| return false; | |
| } | |
| } | |
| // Add a fake extension. See RFC 8701. | |
| if (!CBB_add_u16(&extensions, | |
| ssl_get_grease_value(hs, ssl_grease_ticket_extension)) || | |
| !CBB_add_u16(&extensions, 0 /* empty */)) { | |
| return false; | |
| } | |
| if (!ssl_add_message_cbb(ssl, cbb.get())) { | |
| return false; | |
| } | |
| } | |
| *out_sent_tickets = true; | |
| return true; | |
| } | |
| static enum ssl_hs_wait_t do_select_parameters(SSL_HANDSHAKE *hs) { | |
| // At this point, most ClientHello extensions have already been processed by | |
| // the common handshake logic. Resolve the remaining non-PSK parameters. | |
| SSL *const ssl = hs->ssl; | |
| SSLMessage msg; | |
| SSL_CLIENT_HELLO client_hello; | |
| if (!hs->GetClientHello(&msg, &client_hello)) { | |
| return ssl_hs_error; | |
| } | |
| if (ssl->quic_method != nullptr && client_hello.session_id_len > 0) { | |
| OPENSSL_PUT_ERROR(SSL, SSL_R_UNEXPECTED_COMPATIBILITY_MODE); | |
| ssl_send_alert(ssl, SSL3_AL_FATAL, SSL_AD_ILLEGAL_PARAMETER); | |
| return ssl_hs_error; | |
| } | |
| OPENSSL_memcpy(hs->session_id, client_hello.session_id, | |
| client_hello.session_id_len); | |
| hs->session_id_len = client_hello.session_id_len; | |
| uint16_t group_id; | |
| if (!tls1_get_shared_group(hs, &group_id)) { | |
| OPENSSL_PUT_ERROR(SSL, SSL_R_NO_SHARED_GROUP); | |
| ssl_send_alert(ssl, SSL3_AL_FATAL, SSL_AD_HANDSHAKE_FAILURE); | |
| return ssl_hs_error; | |
| } | |
| // Negotiate the cipher suite. | |
| hs->new_cipher = choose_tls13_cipher(ssl, &client_hello, group_id); | |
| if (hs->new_cipher == NULL) { | |
| OPENSSL_PUT_ERROR(SSL, SSL_R_NO_SHARED_CIPHER); | |
| ssl_send_alert(ssl, SSL3_AL_FATAL, SSL_AD_HANDSHAKE_FAILURE); | |
| return ssl_hs_error; | |
| } | |
| // HTTP/2 negotiation depends on the cipher suite, so ALPN negotiation was | |
| // deferred. Complete it now. | |
| uint8_t alert = SSL_AD_DECODE_ERROR; | |
| if (!ssl_negotiate_alpn(hs, &alert, &client_hello)) { | |
| ssl_send_alert(ssl, SSL3_AL_FATAL, alert); | |
| return ssl_hs_error; | |
| } | |
| // The PRF hash is now known. | |
| if (!hs->transcript.InitHash(ssl_protocol_version(ssl), hs->new_cipher)) { | |
| return ssl_hs_error; | |
| } | |
| hs->tls13_state = state13_select_session; | |
| return ssl_hs_ok; | |
| } | |
| static enum ssl_ticket_aead_result_t select_session( | |
| SSL_HANDSHAKE *hs, uint8_t *out_alert, UniquePtr<SSL_SESSION> *out_session, | |
| int32_t *out_ticket_age_skew, bool *out_offered_ticket, | |
| const SSLMessage &msg, const SSL_CLIENT_HELLO *client_hello) { | |
| SSL *const ssl = hs->ssl; | |
| *out_session = nullptr; | |
| CBS pre_shared_key; | |
| *out_offered_ticket = ssl_client_hello_get_extension( | |
| client_hello, &pre_shared_key, TLSEXT_TYPE_pre_shared_key); | |
| if (!*out_offered_ticket) { | |
| return ssl_ticket_aead_ignore_ticket; | |
| } | |
| // Per RFC 8446, section 4.2.9, servers MUST abort the handshake if the client | |
| // sends pre_shared_key without psk_key_exchange_modes. | |
| CBS unused; | |
| if (!ssl_client_hello_get_extension(client_hello, &unused, | |
| TLSEXT_TYPE_psk_key_exchange_modes)) { | |
| *out_alert = SSL_AD_MISSING_EXTENSION; | |
| OPENSSL_PUT_ERROR(SSL, SSL_R_MISSING_EXTENSION); | |
| return ssl_ticket_aead_error; | |
| } | |
| CBS ticket, binders; | |
| uint32_t client_ticket_age; | |
| if (!ssl_ext_pre_shared_key_parse_clienthello( | |
| hs, &ticket, &binders, &client_ticket_age, out_alert, client_hello, | |
| &pre_shared_key)) { | |
| return ssl_ticket_aead_error; | |
| } | |
| // If the peer did not offer psk_dhe, ignore the resumption. | |
| if (!hs->accept_psk_mode) { | |
| return ssl_ticket_aead_ignore_ticket; | |
| } | |
| // TLS 1.3 session tickets are renewed separately as part of the | |
| // NewSessionTicket. | |
| bool unused_renew; | |
| UniquePtr<SSL_SESSION> session; | |
| enum ssl_ticket_aead_result_t ret = | |
| ssl_process_ticket(hs, &session, &unused_renew, ticket, {}); | |
| switch (ret) { | |
| case ssl_ticket_aead_success: | |
| break; | |
| case ssl_ticket_aead_error: | |
| *out_alert = SSL_AD_INTERNAL_ERROR; | |
| return ret; | |
| default: | |
| return ret; | |
| } | |
| if (!ssl_session_is_resumable(hs, session.get()) || | |
| // Historically, some TLS 1.3 tickets were missing ticket_age_add. | |
| !session->ticket_age_add_valid) { | |
| return ssl_ticket_aead_ignore_ticket; | |
| } | |
| // Recover the client ticket age and convert to seconds. | |
| client_ticket_age -= session->ticket_age_add; | |
| client_ticket_age /= 1000; | |
| struct OPENSSL_timeval now; | |
| ssl_get_current_time(ssl, &now); | |
| // Compute the server ticket age in seconds. | |
| assert(now.tv_sec >= session->time); | |
| uint64_t server_ticket_age = now.tv_sec - session->time; | |
| // To avoid overflowing |hs->ticket_age_skew|, we will not resume | |
| // 68-year-old sessions. | |
| if (server_ticket_age > INT32_MAX) { | |
| return ssl_ticket_aead_ignore_ticket; | |
| } | |
| *out_ticket_age_skew = static_cast<int32_t>(client_ticket_age) - | |
| static_cast<int32_t>(server_ticket_age); | |
| // Check the PSK binder. | |
| if (!tls13_verify_psk_binder(hs, session.get(), msg, &binders)) { | |
| *out_alert = SSL_AD_DECRYPT_ERROR; | |
| return ssl_ticket_aead_error; | |
| } | |
| *out_session = std::move(session); | |
| return ssl_ticket_aead_success; | |
| } | |
| static bool quic_ticket_compatible(const SSL_SESSION *session, | |
| const SSL_CONFIG *config) { | |
| if (!session->is_quic) { | |
| return true; | |
| } | |
| if (session->quic_early_data_context.empty() || | |
| config->quic_early_data_context.size() != | |
| session->quic_early_data_context.size() || | |
| CRYPTO_memcmp(config->quic_early_data_context.data(), | |
| session->quic_early_data_context.data(), | |
| session->quic_early_data_context.size()) != 0) { | |
| return false; | |
| } | |
| return true; | |
| } | |
| static enum ssl_hs_wait_t do_select_session(SSL_HANDSHAKE *hs) { | |
| SSL *const ssl = hs->ssl; | |
| SSLMessage msg; | |
| SSL_CLIENT_HELLO client_hello; | |
| if (!hs->GetClientHello(&msg, &client_hello)) { | |
| return ssl_hs_error; | |
| } | |
| uint8_t alert = SSL_AD_DECODE_ERROR; | |
| UniquePtr<SSL_SESSION> session; | |
| bool offered_ticket = false; | |
| switch (select_session(hs, &alert, &session, &ssl->s3->ticket_age_skew, | |
| &offered_ticket, msg, &client_hello)) { | |
| case ssl_ticket_aead_ignore_ticket: | |
| assert(!session); | |
| if (!ssl_get_new_session(hs)) { | |
| ssl_send_alert(ssl, SSL3_AL_FATAL, SSL_AD_INTERNAL_ERROR); | |
| return ssl_hs_error; | |
| } | |
| break; | |
| case ssl_ticket_aead_success: | |
| // Carry over authentication information from the previous handshake into | |
| // a fresh session. | |
| hs->new_session = | |
| SSL_SESSION_dup(session.get(), SSL_SESSION_DUP_AUTH_ONLY); | |
| if (hs->new_session == nullptr) { | |
| ssl_send_alert(ssl, SSL3_AL_FATAL, SSL_AD_INTERNAL_ERROR); | |
| return ssl_hs_error; | |
| } | |
| ssl->s3->session_reused = true; | |
| hs->can_release_private_key = true; | |
| // 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); | |
| break; | |
| case ssl_ticket_aead_error: | |
| ssl_send_alert(ssl, SSL3_AL_FATAL, alert); | |
| return ssl_hs_error; | |
| case ssl_ticket_aead_retry: | |
| hs->tls13_state = state13_select_session; | |
| return ssl_hs_pending_ticket; | |
| } | |
| // Negotiate ALPS now, after ALPN is negotiated and |hs->new_session| is | |
| // initialized. | |
| if (!ssl_negotiate_alps(hs, &alert, &client_hello)) { | |
| ssl_send_alert(ssl, SSL3_AL_FATAL, alert); | |
| return ssl_hs_error; | |
| } | |
| // Record connection properties in the new session. | |
| hs->new_session->cipher = hs->new_cipher; | |
| if (!tls1_get_shared_group(hs, &hs->new_session->group_id)) { | |
| OPENSSL_PUT_ERROR(SSL, SSL_R_NO_SHARED_GROUP); | |
| ssl_send_alert(ssl, SSL3_AL_FATAL, SSL_AD_HANDSHAKE_FAILURE); | |
| return ssl_hs_error; | |
| } | |
| // Determine if we need HelloRetryRequest. | |
| bool found_key_share; | |
| if (!ssl_ext_key_share_parse_clienthello(hs, &found_key_share, | |
| /*out_key_share=*/nullptr, &alert, | |
| &client_hello)) { | |
| ssl_send_alert(ssl, SSL3_AL_FATAL, alert); | |
| return ssl_hs_error; | |
| } | |
| // Determine if we're negotiating 0-RTT. | |
| if (!ssl->enable_early_data) { | |
| ssl->s3->early_data_reason = ssl_early_data_disabled; | |
| } else if (!offered_ticket) { | |
| ssl->s3->early_data_reason = ssl_early_data_no_session_offered; | |
| } else if (!session) { | |
| ssl->s3->early_data_reason = ssl_early_data_session_not_resumed; | |
| } else if (session->ticket_max_early_data == 0) { | |
| ssl->s3->early_data_reason = ssl_early_data_unsupported_for_session; | |
| } else if (!hs->early_data_offered) { | |
| ssl->s3->early_data_reason = ssl_early_data_peer_declined; | |
| } else if (hs->channel_id_negotiated) { | |
| // Channel ID is incompatible with 0-RTT. | |
| ssl->s3->early_data_reason = ssl_early_data_channel_id; | |
| } else if (MakeConstSpan(ssl->s3->alpn_selected) != session->early_alpn) { | |
| // The negotiated ALPN must match the one in the ticket. | |
| ssl->s3->early_data_reason = ssl_early_data_alpn_mismatch; | |
| } else if (hs->new_session->has_application_settings != | |
| session->has_application_settings || | |
| MakeConstSpan(hs->new_session->local_application_settings) != | |
| session->local_application_settings) { | |
| ssl->s3->early_data_reason = ssl_early_data_alps_mismatch; | |
| } else if (ssl->s3->ticket_age_skew < -kMaxTicketAgeSkewSeconds || | |
| kMaxTicketAgeSkewSeconds < ssl->s3->ticket_age_skew) { | |
| ssl->s3->early_data_reason = ssl_early_data_ticket_age_skew; | |
| } else if (!quic_ticket_compatible(session.get(), hs->config)) { | |
| ssl->s3->early_data_reason = ssl_early_data_quic_parameter_mismatch; | |
| } else if (!found_key_share) { | |
| ssl->s3->early_data_reason = ssl_early_data_hello_retry_request; | |
| } else { | |
| // |ssl_session_is_resumable| forbids cross-cipher resumptions even if the | |
| // PRF hashes match. | |
| assert(hs->new_cipher == session->cipher); | |
| ssl->s3->early_data_reason = ssl_early_data_accepted; | |
| ssl->s3->early_data_accepted = true; | |
| } | |
| // Store the ALPN and ALPS values in the session for 0-RTT. Note the peer | |
| // applications settings are not generally known until client | |
| // EncryptedExtensions. | |
| 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; | |
| } | |
| // The peer applications settings are usually received later, in | |
| // EncryptedExtensions. But, in 0-RTT handshakes, we carry over the | |
| // values from |session|. Do this now, before |session| is discarded. | |
| if (ssl->s3->early_data_accepted && | |
| hs->new_session->has_application_settings && | |
| !hs->new_session->peer_application_settings.CopyFrom( | |
| session->peer_application_settings)) { | |
| ssl_send_alert(ssl, SSL3_AL_FATAL, SSL_AD_INTERNAL_ERROR); | |
| return ssl_hs_error; | |
| } | |
| // Copy the QUIC early data context to the session. | |
| if (ssl->enable_early_data && ssl->quic_method) { | |
| if (!hs->new_session->quic_early_data_context.CopyFrom( | |
| hs->config->quic_early_data_context)) { | |
| ssl_send_alert(ssl, SSL3_AL_FATAL, SSL_AD_INTERNAL_ERROR); | |
| return ssl_hs_error; | |
| } | |
| } | |
| if (ssl->ctx->dos_protection_cb != NULL && | |
| ssl->ctx->dos_protection_cb(&client_hello) == 0) { | |
| // Connection rejected for DOS reasons. | |
| OPENSSL_PUT_ERROR(SSL, SSL_R_CONNECTION_REJECTED); | |
| ssl_send_alert(ssl, SSL3_AL_FATAL, SSL_AD_INTERNAL_ERROR); | |
| return ssl_hs_error; | |
| } | |
| size_t hash_len = EVP_MD_size( | |
| ssl_get_handshake_digest(ssl_protocol_version(ssl), hs->new_cipher)); | |
| // Set up the key schedule and incorporate the PSK into the running secret. | |
| if (!tls13_init_key_schedule( | |
| hs, ssl->s3->session_reused | |
| ? MakeConstSpan(hs->new_session->secret, | |
| hs->new_session->secret_length) | |
| : MakeConstSpan(kZeroes, hash_len)) || | |
| !ssl_hash_message(hs, msg)) { | |
| return ssl_hs_error; | |
| } | |
| if (ssl->s3->early_data_accepted) { | |
| if (!tls13_derive_early_secret(hs)) { | |
| return ssl_hs_error; | |
| } | |
| } else if (hs->early_data_offered) { | |
| ssl->s3->skip_early_data = true; | |
| } | |
| if (!found_key_share) { | |
| ssl->method->next_message(ssl); | |
| if (!hs->transcript.UpdateForHelloRetryRequest()) { | |
| return ssl_hs_error; | |
| } | |
| hs->tls13_state = state13_send_hello_retry_request; | |
| return ssl_hs_ok; | |
| } | |
| if (!resolve_ecdhe_secret(hs, &client_hello)) { | |
| return ssl_hs_error; | |
| } | |
| ssl->method->next_message(ssl); | |
| hs->ech_client_hello_buf.Reset(); | |
| hs->tls13_state = state13_send_server_hello; | |
| return ssl_hs_ok; | |
| } | |
| static enum ssl_hs_wait_t do_send_hello_retry_request(SSL_HANDSHAKE *hs) { | |
| SSL *const ssl = hs->ssl; | |
| if (hs->hints_requested) { | |
| return ssl_hs_hints_ready; | |
| } | |
| ScopedCBB cbb; | |
| CBB body, session_id, extensions; | |
| uint16_t group_id; | |
| if (!ssl->method->init_message(ssl, cbb.get(), &body, SSL3_MT_SERVER_HELLO) || | |
| !CBB_add_u16(&body, TLS1_2_VERSION) || | |
| !CBB_add_bytes(&body, kHelloRetryRequest, SSL3_RANDOM_SIZE) || | |
| !CBB_add_u8_length_prefixed(&body, &session_id) || | |
| !CBB_add_bytes(&session_id, hs->session_id, hs->session_id_len) || | |
| !CBB_add_u16(&body, SSL_CIPHER_get_protocol_id(hs->new_cipher)) || | |
| !CBB_add_u8(&body, 0 /* no compression */) || | |
| !tls1_get_shared_group(hs, &group_id) || | |
| !CBB_add_u16_length_prefixed(&body, &extensions) || | |
| !CBB_add_u16(&extensions, TLSEXT_TYPE_supported_versions) || | |
| !CBB_add_u16(&extensions, 2 /* length */) || | |
| !CBB_add_u16(&extensions, ssl->version) || | |
| !CBB_add_u16(&extensions, TLSEXT_TYPE_key_share) || | |
| !CBB_add_u16(&extensions, 2 /* length */) || | |
| !CBB_add_u16(&extensions, group_id)) { | |
| return ssl_hs_error; | |
| } | |
| if (hs->ech_is_inner) { | |
| // Fill a placeholder for the ECH confirmation value. | |
| if (!CBB_add_u16(&extensions, TLSEXT_TYPE_encrypted_client_hello) || | |
| !CBB_add_u16(&extensions, ECH_CONFIRMATION_SIGNAL_LEN) || | |
| !CBB_add_zeros(&extensions, ECH_CONFIRMATION_SIGNAL_LEN)) { | |
| return ssl_hs_error; | |
| } | |
| } | |
| Array<uint8_t> hrr; | |
| if (!ssl->method->finish_message(ssl, cbb.get(), &hrr)) { | |
| return ssl_hs_error; | |
| } | |
| if (hs->ech_is_inner) { | |
| // Now that the message is encoded, fill in the whole value. | |
| size_t offset = hrr.size() - ECH_CONFIRMATION_SIGNAL_LEN; | |
| if (!ssl_ech_accept_confirmation( | |
| hs, MakeSpan(hrr).last(ECH_CONFIRMATION_SIGNAL_LEN), | |
| ssl->s3->client_random, hs->transcript, /*is_hrr=*/true, hrr, | |
| offset)) { | |
| return ssl_hs_error; | |
| } | |
| } | |
| if (!ssl->method->add_message(ssl, std::move(hrr)) || | |
| !ssl->method->add_change_cipher_spec(ssl)) { | |
| return ssl_hs_error; | |
| } | |
| ssl->s3->used_hello_retry_request = true; | |
| hs->tls13_state = state13_read_second_client_hello; | |
| return ssl_hs_flush; | |
| } | |
| static enum ssl_hs_wait_t do_read_second_client_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_CLIENT_HELLO)) { | |
| return ssl_hs_error; | |
| } | |
| SSL_CLIENT_HELLO client_hello; | |
| if (!ssl_client_hello_init(ssl, &client_hello, msg.body)) { | |
| OPENSSL_PUT_ERROR(SSL, SSL_R_CLIENTHELLO_PARSE_FAILED); | |
| ssl_send_alert(ssl, SSL3_AL_FATAL, SSL_AD_DECODE_ERROR); | |
| return ssl_hs_error; | |
| } | |
| if (ssl->s3->ech_status == ssl_ech_accepted) { | |
| // If we previously accepted the ClientHelloInner, the second ClientHello | |
| // must contain an outer encrypted_client_hello extension. | |
| CBS ech_body; | |
| if (!ssl_client_hello_get_extension(&client_hello, &ech_body, | |
| TLSEXT_TYPE_encrypted_client_hello)) { | |
| OPENSSL_PUT_ERROR(SSL, SSL_R_MISSING_EXTENSION); | |
| ssl_send_alert(ssl, SSL3_AL_FATAL, SSL_AD_MISSING_EXTENSION); | |
| return ssl_hs_error; | |
| } | |
| uint16_t kdf_id, aead_id; | |
| uint8_t type, config_id; | |
| CBS enc, payload; | |
| if (!CBS_get_u8(&ech_body, &type) || // | |
| type != ECH_CLIENT_OUTER || // | |
| !CBS_get_u16(&ech_body, &kdf_id) || // | |
| !CBS_get_u16(&ech_body, &aead_id) || | |
| !CBS_get_u8(&ech_body, &config_id) || | |
| !CBS_get_u16_length_prefixed(&ech_body, &enc) || | |
| !CBS_get_u16_length_prefixed(&ech_body, &payload) || | |
| CBS_len(&ech_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 (kdf_id != EVP_HPKE_KDF_id(EVP_HPKE_CTX_kdf(hs->ech_hpke_ctx.get())) || | |
| aead_id != | |
| EVP_HPKE_AEAD_id(EVP_HPKE_CTX_aead(hs->ech_hpke_ctx.get())) || | |
| config_id != hs->ech_config_id || CBS_len(&enc) > 0) { | |
| OPENSSL_PUT_ERROR(SSL, SSL_R_DECODE_ERROR); | |
| ssl_send_alert(ssl, SSL3_AL_FATAL, SSL_AD_ILLEGAL_PARAMETER); | |
| return ssl_hs_error; | |
| } | |
| // Decrypt the payload with the HPKE context from the first ClientHello. | |
| Array<uint8_t> encoded_client_hello_inner; | |
| bool unused; | |
| if (!ssl_client_hello_decrypt(hs->ech_hpke_ctx.get(), | |
| &encoded_client_hello_inner, &unused, | |
| &client_hello, payload)) { | |
| // Decryption failure is fatal in the second ClientHello. | |
| OPENSSL_PUT_ERROR(SSL, SSL_R_DECRYPTION_FAILED); | |
| ssl_send_alert(ssl, SSL3_AL_FATAL, SSL_AD_DECRYPT_ERROR); | |
| return ssl_hs_error; | |
| } | |
| // Recover the ClientHelloInner from the EncodedClientHelloInner. | |
| uint8_t alert = SSL_AD_DECODE_ERROR; | |
| bssl::Array<uint8_t> client_hello_inner; | |
| if (!ssl_decode_client_hello_inner(ssl, &alert, &client_hello_inner, | |
| encoded_client_hello_inner, | |
| &client_hello)) { | |
| OPENSSL_PUT_ERROR(SSL, SSL_R_DECODE_ERROR); | |
| ssl_send_alert(ssl, SSL3_AL_FATAL, alert); | |
| return ssl_hs_error; | |
| } | |
| hs->ech_client_hello_buf = std::move(client_hello_inner); | |
| // Reparse |client_hello| from the buffer owned by |hs|. | |
| if (!hs->GetClientHello(&msg, &client_hello)) { | |
| OPENSSL_PUT_ERROR(SSL, ERR_R_INTERNAL_ERROR); | |
| return ssl_hs_error; | |
| } | |
| } | |
| // We perform all our negotiation based on the first ClientHello (for | |
| // consistency with what |select_certificate_cb| observed), which is in the | |
| // transcript, so we can ignore most of this second one. | |
| // | |
| // We do, however, check the second PSK binder. This covers the client key | |
| // share, in case we ever send half-RTT data (we currently do not). It is also | |
| // a tricky computation, so we enforce the peer handled it correctly. | |
| if (ssl->s3->session_reused) { | |
| CBS pre_shared_key; | |
| if (!ssl_client_hello_get_extension(&client_hello, &pre_shared_key, | |
| TLSEXT_TYPE_pre_shared_key)) { | |
| OPENSSL_PUT_ERROR(SSL, SSL_R_INCONSISTENT_CLIENT_HELLO); | |
| ssl_send_alert(ssl, SSL3_AL_FATAL, SSL_AD_ILLEGAL_PARAMETER); | |
| return ssl_hs_error; | |
| } | |
| CBS ticket, binders; | |
| uint32_t client_ticket_age; | |
| uint8_t alert = SSL_AD_DECODE_ERROR; | |
| if (!ssl_ext_pre_shared_key_parse_clienthello( | |
| hs, &ticket, &binders, &client_ticket_age, &alert, &client_hello, | |
| &pre_shared_key)) { | |
| ssl_send_alert(ssl, SSL3_AL_FATAL, alert); | |
| return ssl_hs_error; | |
| } | |
| // Note it is important that we do not obtain a new |SSL_SESSION| from | |
| // |ticket|. We have already selected parameters based on the first | |
| // ClientHello (in the transcript) and must not switch partway through. | |
| if (!tls13_verify_psk_binder(hs, hs->new_session.get(), msg, &binders)) { | |
| ssl_send_alert(ssl, SSL3_AL_FATAL, SSL_AD_DECRYPT_ERROR); | |
| return ssl_hs_error; | |
| } | |
| } | |
| if (!resolve_ecdhe_secret(hs, &client_hello)) { | |
| return ssl_hs_error; | |
| } | |
| if (!ssl_hash_message(hs, msg)) { | |
| return ssl_hs_error; | |
| } | |
| // ClientHello 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->ech_client_hello_buf.Reset(); | |
| hs->tls13_state = state13_send_server_hello; | |
| return ssl_hs_ok; | |
| } | |
| static enum ssl_hs_wait_t do_send_server_hello(SSL_HANDSHAKE *hs) { | |
| SSL *const ssl = hs->ssl; | |
| Span<uint8_t> random(ssl->s3->server_random); | |
| SSL_HANDSHAKE_HINTS *const hints = hs->hints.get(); | |
| if (hints && !hs->hints_requested && | |
| hints->server_random.size() == random.size()) { | |
| OPENSSL_memcpy(random.data(), hints->server_random.data(), random.size()); | |
| } else { | |
| RAND_bytes(random.data(), random.size()); | |
| if (hints && hs->hints_requested && | |
| !hints->server_random.CopyFrom(random)) { | |
| return ssl_hs_error; | |
| } | |
| } | |
| Array<uint8_t> server_hello; | |
| ScopedCBB cbb; | |
| CBB body, extensions, session_id; | |
| if (!ssl->method->init_message(ssl, cbb.get(), &body, SSL3_MT_SERVER_HELLO) || | |
| !CBB_add_u16(&body, TLS1_2_VERSION) || | |
| !CBB_add_bytes(&body, ssl->s3->server_random, | |
| sizeof(ssl->s3->server_random)) || | |
| !CBB_add_u8_length_prefixed(&body, &session_id) || | |
| !CBB_add_bytes(&session_id, hs->session_id, hs->session_id_len) || | |
| !CBB_add_u16(&body, SSL_CIPHER_get_protocol_id(hs->new_cipher)) || | |
| !CBB_add_u8(&body, 0) || | |
| !CBB_add_u16_length_prefixed(&body, &extensions) || | |
| !ssl_ext_pre_shared_key_add_serverhello(hs, &extensions) || | |
| !ssl_ext_key_share_add_serverhello(hs, &extensions) || | |
| !ssl_ext_supported_versions_add_serverhello(hs, &extensions) || | |
| !ssl->method->finish_message(ssl, cbb.get(), &server_hello)) { | |
| return ssl_hs_error; | |
| } | |
| assert(ssl->s3->ech_status != ssl_ech_accepted || hs->ech_is_inner); | |
| if (hs->ech_is_inner) { | |
| // Fill in the ECH confirmation signal. | |
| const size_t offset = ssl_ech_confirmation_signal_hello_offset(ssl); | |
| Span<uint8_t> random_suffix = random.last(ECH_CONFIRMATION_SIGNAL_LEN); | |
| if (!ssl_ech_accept_confirmation(hs, random_suffix, ssl->s3->client_random, | |
| hs->transcript, | |
| /*is_hrr=*/false, server_hello, offset)) { | |
| return ssl_hs_error; | |
| } | |
| // Update |server_hello|. | |
| Span<uint8_t> server_hello_out = | |
| MakeSpan(server_hello).subspan(offset, ECH_CONFIRMATION_SIGNAL_LEN); | |
| OPENSSL_memcpy(server_hello_out.data(), random_suffix.data(), | |
| ECH_CONFIRMATION_SIGNAL_LEN); | |
| } | |
| if (!ssl->method->add_message(ssl, std::move(server_hello))) { | |
| return ssl_hs_error; | |
| } | |
| hs->ecdh_public_key.Reset(); // No longer needed. | |
| if (!ssl->s3->used_hello_retry_request && | |
| !ssl->method->add_change_cipher_spec(ssl)) { | |
| return ssl_hs_error; | |
| } | |
| // Derive and enable the handshake traffic secrets. | |
| if (!tls13_derive_handshake_secrets(hs) || | |
| !tls13_set_traffic_key(ssl, ssl_encryption_handshake, evp_aead_seal, | |
| hs->new_session.get(), | |
| hs->server_handshake_secret())) { | |
| return ssl_hs_error; | |
| } | |
| // Send EncryptedExtensions. | |
| if (!ssl->method->init_message(ssl, cbb.get(), &body, | |
| SSL3_MT_ENCRYPTED_EXTENSIONS) || | |
| !ssl_add_serverhello_tlsext(hs, &body) || | |
| !ssl_add_message_cbb(ssl, cbb.get())) { | |
| return ssl_hs_error; | |
| } | |
| if (!ssl->s3->session_reused) { | |
| // Determine whether to request a client certificate. | |
| hs->cert_request = !!(hs->config->verify_mode & SSL_VERIFY_PEER); | |
| // Only request a certificate if Channel ID isn't negotiated. | |
| if ((hs->config->verify_mode & SSL_VERIFY_PEER_IF_NO_OBC) && | |
| hs->channel_id_negotiated) { | |
| hs->cert_request = false; | |
| } | |
| } | |
| // Send a CertificateRequest, if necessary. | |
| if (hs->cert_request) { | |
| CBB cert_request_extensions, sigalg_contents, sigalgs_cbb; | |
| if (!ssl->method->init_message(ssl, cbb.get(), &body, | |
| SSL3_MT_CERTIFICATE_REQUEST) || | |
| !CBB_add_u8(&body, 0 /* no certificate_request_context. */) || | |
| !CBB_add_u16_length_prefixed(&body, &cert_request_extensions) || | |
| !CBB_add_u16(&cert_request_extensions, | |
| TLSEXT_TYPE_signature_algorithms) || | |
| !CBB_add_u16_length_prefixed(&cert_request_extensions, | |
| &sigalg_contents) || | |
| !CBB_add_u16_length_prefixed(&sigalg_contents, &sigalgs_cbb) || | |
| !tls12_add_verify_sigalgs(hs, &sigalgs_cbb)) { | |
| return ssl_hs_error; | |
| } | |
| if (ssl_has_client_CAs(hs->config)) { | |
| CBB ca_contents; | |
| if (!CBB_add_u16(&cert_request_extensions, | |
| TLSEXT_TYPE_certificate_authorities) || | |
| !CBB_add_u16_length_prefixed(&cert_request_extensions, | |
| &ca_contents) || | |
| !ssl_add_client_CA_list(hs, &ca_contents) || | |
| !CBB_flush(&cert_request_extensions)) { | |
| return ssl_hs_error; | |
| } | |
| } | |
| if (!ssl_add_message_cbb(ssl, cbb.get())) { | |
| return ssl_hs_error; | |
| } | |
| } | |
| // Send the server Certificate message, if necessary. | |
| if (!ssl->s3->session_reused) { | |
| if (!ssl_has_certificate(hs)) { | |
| OPENSSL_PUT_ERROR(SSL, SSL_R_NO_CERTIFICATE_SET); | |
| return ssl_hs_error; | |
| } | |
| if (!tls13_add_certificate(hs)) { | |
| return ssl_hs_error; | |
| } | |
| hs->tls13_state = state13_send_server_certificate_verify; | |
| return ssl_hs_ok; | |
| } | |
| hs->tls13_state = state13_send_server_finished; | |
| return ssl_hs_ok; | |
| } | |
| static enum ssl_hs_wait_t do_send_server_certificate_verify(SSL_HANDSHAKE *hs) { | |
| switch (tls13_add_certificate_verify(hs)) { | |
| case ssl_private_key_success: | |
| hs->tls13_state = state13_send_server_finished; | |
| return ssl_hs_ok; | |
| case ssl_private_key_retry: | |
| hs->tls13_state = state13_send_server_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_send_server_finished(SSL_HANDSHAKE *hs) { | |
| SSL *const ssl = hs->ssl; | |
| if (hs->hints_requested) { | |
| return ssl_hs_hints_ready; | |
| } | |
| hs->can_release_private_key = true; | |
| if (!tls13_add_finished(hs) || | |
| // 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) || | |
| !tls13_set_traffic_key(ssl, ssl_encryption_application, evp_aead_seal, | |
| hs->new_session.get(), | |
| hs->server_traffic_secret_0())) { | |
| return ssl_hs_error; | |
| } | |
| hs->tls13_state = state13_send_half_rtt_ticket; | |
| return hs->handback ? ssl_hs_handback : ssl_hs_ok; | |
| } | |
| static enum ssl_hs_wait_t do_send_half_rtt_ticket(SSL_HANDSHAKE *hs) { | |
| SSL *const ssl = hs->ssl; | |
| if (ssl->s3->early_data_accepted) { | |
| // If accepting 0-RTT, we send tickets half-RTT. This gets the tickets on | |
| // the wire sooner and also avoids triggering a write on |SSL_read| when | |
| // processing the client Finished. This requires computing the client | |
| // Finished early. See RFC 8446, section 4.6.1. | |
| static const uint8_t kEndOfEarlyData[4] = {SSL3_MT_END_OF_EARLY_DATA, 0, | |
| 0, 0}; | |
| if (ssl->quic_method == nullptr && | |
| !hs->transcript.Update(kEndOfEarlyData)) { | |
| OPENSSL_PUT_ERROR(SSL, ERR_R_INTERNAL_ERROR); | |
| return ssl_hs_error; | |
| } | |
| size_t finished_len; | |
| if (!tls13_finished_mac(hs, hs->expected_client_finished().data(), | |
| &finished_len, false /* client */)) { | |
| return ssl_hs_error; | |
| } | |
| if (finished_len != hs->expected_client_finished().size()) { | |
| OPENSSL_PUT_ERROR(SSL, ERR_R_INTERNAL_ERROR); | |
| return ssl_hs_error; | |
| } | |
| // Feed the predicted Finished into the transcript. This allows us to derive | |
| // the resumption secret early and send half-RTT tickets. | |
| // | |
| // TODO(davidben): This will need to be updated for DTLS 1.3. | |
| assert(!SSL_is_dtls(hs->ssl)); | |
| assert(hs->expected_client_finished().size() <= 0xff); | |
| uint8_t header[4] = { | |
| SSL3_MT_FINISHED, 0, 0, | |
| static_cast<uint8_t>(hs->expected_client_finished().size())}; | |
| bool unused_sent_tickets; | |
| if (!hs->transcript.Update(header) || | |
| !hs->transcript.Update(hs->expected_client_finished()) || | |
| !tls13_derive_resumption_secret(hs) || | |
| !add_new_session_tickets(hs, &unused_sent_tickets)) { | |
| return ssl_hs_error; | |
| } | |
| } | |
| hs->tls13_state = state13_read_second_client_flight; | |
| return ssl_hs_flush; | |
| } | |
| static enum ssl_hs_wait_t do_read_second_client_flight(SSL_HANDSHAKE *hs) { | |
| SSL *const ssl = hs->ssl; | |
| if (ssl->s3->early_data_accepted) { | |
| if (!tls13_set_traffic_key(ssl, ssl_encryption_early_data, evp_aead_open, | |
| hs->new_session.get(), | |
| hs->early_traffic_secret())) { | |
| return ssl_hs_error; | |
| } | |
| hs->can_early_write = true; | |
| hs->can_early_read = true; | |
| hs->in_early_data = true; | |
| } | |
| // QUIC doesn't use an EndOfEarlyData message (RFC 9001, section 8.3), so we | |
| // switch to client_handshake_secret before the early return. | |
| if (ssl->quic_method != nullptr) { | |
| if (!tls13_set_traffic_key(ssl, ssl_encryption_handshake, evp_aead_open, | |
| hs->new_session.get(), | |
| hs->client_handshake_secret())) { | |
| return ssl_hs_error; | |
| } | |
| hs->tls13_state = state13_process_end_of_early_data; | |
| return ssl->s3->early_data_accepted ? ssl_hs_early_return : ssl_hs_ok; | |
| } | |
| hs->tls13_state = state13_process_end_of_early_data; | |
| return ssl->s3->early_data_accepted ? ssl_hs_read_end_of_early_data | |
| : ssl_hs_ok; | |
| } | |
| static enum ssl_hs_wait_t do_process_end_of_early_data(SSL_HANDSHAKE *hs) { | |
| SSL *const ssl = hs->ssl; | |
| // In protocols that use EndOfEarlyData, we must consume the extra message and | |
| // switch to client_handshake_secret after the early return. | |
| if (ssl->quic_method == nullptr) { | |
| // If early data was not accepted, the EndOfEarlyData will be in the | |
| // discarded early data. | |
| if (hs->ssl->s3->early_data_accepted) { | |
| SSLMessage msg; | |
| if (!ssl->method->get_message(ssl, &msg)) { | |
| return ssl_hs_read_message; | |
| } | |
| if (!ssl_check_message_type(ssl, msg, SSL3_MT_END_OF_EARLY_DATA)) { | |
| return ssl_hs_error; | |
| } | |
| if (CBS_len(&msg.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; | |
| } | |
| ssl->method->next_message(ssl); | |
| } | |
| if (!tls13_set_traffic_key(ssl, ssl_encryption_handshake, evp_aead_open, | |
| hs->new_session.get(), | |
| hs->client_handshake_secret())) { | |
| return ssl_hs_error; | |
| } | |
| } | |
| hs->tls13_state = state13_read_client_encrypted_extensions; | |
| return ssl_hs_ok; | |
| } | |
| static enum ssl_hs_wait_t do_read_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) { | |
| 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, extensions; | |
| if (!CBS_get_u16_length_prefixed(&body, &extensions) || | |
| 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; | |
| } | |
| SSLExtension application_settings(TLSEXT_TYPE_application_settings); | |
| uint8_t alert = SSL_AD_DECODE_ERROR; | |
| if (!ssl_parse_extensions(&extensions, &alert, {&application_settings}, | |
| /*ignore_unknown=*/false)) { | |
| ssl_send_alert(ssl, SSL3_AL_FATAL, alert); | |
| return ssl_hs_error; | |
| } | |
| if (!application_settings.present) { | |
| OPENSSL_PUT_ERROR(SSL, SSL_R_MISSING_EXTENSION); | |
| ssl_send_alert(ssl, SSL3_AL_FATAL, SSL_AD_MISSING_EXTENSION); | |
| return ssl_hs_error; | |
| } | |
| // Note that, if 0-RTT was accepted, these values will already have been | |
| // initialized earlier. | |
| if (!hs->new_session->peer_application_settings.CopyFrom( | |
| application_settings.data) || | |
| !ssl_hash_message(hs, msg)) { | |
| ssl_send_alert(ssl, SSL3_AL_FATAL, SSL_AD_INTERNAL_ERROR); | |
| return ssl_hs_error; | |
| } | |
| ssl->method->next_message(ssl); | |
| } | |
| hs->tls13_state = state13_read_client_certificate; | |
| return ssl_hs_ok; | |
| } | |
| static enum ssl_hs_wait_t do_read_client_certificate(SSL_HANDSHAKE *hs) { | |
| SSL *const ssl = hs->ssl; | |
| if (!hs->cert_request) { | |
| if (!ssl->s3->session_reused) { | |
| // OpenSSL returns X509_V_OK when no certificates are requested. This is | |
| // classed by them as a bug, but it's assumed by at least NGINX. (Only do | |
| // this in full handshakes as resumptions should carry over the previous | |
| // |verify_result|, though this is a no-op because servers do not | |
| // implement the client's odd soft-fail mode.) | |
| hs->new_session->verify_result = X509_V_OK; | |
| } | |
| // Skip this state. | |
| hs->tls13_state = state13_read_channel_id; | |
| return ssl_hs_ok; | |
| } | |
| const bool allow_anonymous = | |
| (hs->config->verify_mode & SSL_VERIFY_FAIL_IF_NO_PEER_CERT) == 0; | |
| SSLMessage msg; | |
| if (!ssl->method->get_message(ssl, &msg)) { | |
| return ssl_hs_read_message; | |
| } | |
| if (!ssl_check_message_type(ssl, msg, SSL3_MT_CERTIFICATE) || | |
| !tls13_process_certificate(hs, msg, allow_anonymous) || | |
| !ssl_hash_message(hs, msg)) { | |
| return ssl_hs_error; | |
| } | |
| ssl->method->next_message(ssl); | |
| hs->tls13_state = state13_read_client_certificate_verify; | |
| return ssl_hs_ok; | |
| } | |
| static enum ssl_hs_wait_t do_read_client_certificate_verify(SSL_HANDSHAKE *hs) { | |
| SSL *const ssl = hs->ssl; | |
| if (sk_CRYPTO_BUFFER_num(hs->new_session->certs.get()) == 0) { | |
| // Skip this state. | |
| hs->tls13_state = state13_read_channel_id; | |
| return ssl_hs_ok; | |
| } | |
| 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 = state13_read_client_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 = state13_read_channel_id; | |
| return ssl_hs_ok; | |
| } | |
| static enum ssl_hs_wait_t do_read_channel_id(SSL_HANDSHAKE *hs) { | |
| SSL *const ssl = hs->ssl; | |
| if (!hs->channel_id_negotiated) { | |
| hs->tls13_state = state13_read_client_finished; | |
| return ssl_hs_ok; | |
| } | |
| SSLMessage msg; | |
| if (!ssl->method->get_message(ssl, &msg)) { | |
| return ssl_hs_read_message; | |
| } | |
| if (!ssl_check_message_type(ssl, msg, SSL3_MT_CHANNEL_ID) || | |
| !tls1_verify_channel_id(hs, msg) || | |
| !ssl_hash_message(hs, msg)) { | |
| return ssl_hs_error; | |
| } | |
| ssl->method->next_message(ssl); | |
| hs->tls13_state = state13_read_client_finished; | |
| return ssl_hs_ok; | |
| } | |
| static enum ssl_hs_wait_t do_read_client_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) || | |
| // If early data was accepted, we've already computed the client Finished | |
| // and derived the resumption secret. | |
| !tls13_process_finished(hs, msg, ssl->s3->early_data_accepted) || | |
| // evp_aead_seal keys have already been switched. | |
| !tls13_set_traffic_key(ssl, ssl_encryption_application, evp_aead_open, | |
| hs->new_session.get(), | |
| hs->client_traffic_secret_0())) { | |
| return ssl_hs_error; | |
| } | |
| if (!ssl->s3->early_data_accepted) { | |
| if (!ssl_hash_message(hs, msg) || | |
| !tls13_derive_resumption_secret(hs)) { | |
| return ssl_hs_error; | |
| } | |
| // We send post-handshake tickets as part of the handshake in 1-RTT. | |
| hs->tls13_state = state13_send_new_session_ticket; | |
| } else { | |
| // We already sent half-RTT tickets. | |
| hs->tls13_state = state13_done; | |
| } | |
| ssl->method->next_message(ssl); | |
| return ssl_hs_ok; | |
| } | |
| static enum ssl_hs_wait_t do_send_new_session_ticket(SSL_HANDSHAKE *hs) { | |
| bool sent_tickets; | |
| if (!add_new_session_tickets(hs, &sent_tickets)) { | |
| return ssl_hs_error; | |
| } | |
| hs->tls13_state = state13_done; | |
| // In TLS 1.3, the NewSessionTicket isn't flushed until the server performs a | |
| // write, to prevent a non-reading client from causing the server to hang in | |
| // the case of a small server write buffer. Consumers which don't write data | |
| // to the client will need to do a zero-byte write if they wish to flush the | |
| // tickets. | |
| if (hs->ssl->quic_method != nullptr && sent_tickets) { | |
| return ssl_hs_flush; | |
| } | |
| return ssl_hs_ok; | |
| } | |
| enum ssl_hs_wait_t tls13_server_handshake(SSL_HANDSHAKE *hs) { | |
| while (hs->tls13_state != state13_done) { | |
| enum ssl_hs_wait_t ret = ssl_hs_error; | |
| enum tls13_server_hs_state_t state = | |
| static_cast<enum tls13_server_hs_state_t>(hs->tls13_state); | |
| switch (state) { | |
| case state13_select_parameters: | |
| ret = do_select_parameters(hs); | |
| break; | |
| case state13_select_session: | |
| ret = do_select_session(hs); | |
| break; | |
| case state13_send_hello_retry_request: | |
| ret = do_send_hello_retry_request(hs); | |
| break; | |
| case state13_read_second_client_hello: | |
| ret = do_read_second_client_hello(hs); | |
| break; | |
| case state13_send_server_hello: | |
| ret = do_send_server_hello(hs); | |
| break; | |
| case state13_send_server_certificate_verify: | |
| ret = do_send_server_certificate_verify(hs); | |
| break; | |
| case state13_send_server_finished: | |
| ret = do_send_server_finished(hs); | |
| break; | |
| case state13_send_half_rtt_ticket: | |
| ret = do_send_half_rtt_ticket(hs); | |
| break; | |
| case state13_read_second_client_flight: | |
| ret = do_read_second_client_flight(hs); | |
| break; | |
| case state13_process_end_of_early_data: | |
| ret = do_process_end_of_early_data(hs); | |
| break; | |
| case state13_read_client_encrypted_extensions: | |
| ret = do_read_client_encrypted_extensions(hs); | |
| break; | |
| case state13_read_client_certificate: | |
| ret = do_read_client_certificate(hs); | |
| break; | |
| case state13_read_client_certificate_verify: | |
| ret = do_read_client_certificate_verify(hs); | |
| break; | |
| case state13_read_channel_id: | |
| ret = do_read_channel_id(hs); | |
| break; | |
| case state13_read_client_finished: | |
| ret = do_read_client_finished(hs); | |
| break; | |
| case state13_send_new_session_ticket: | |
| ret = do_send_new_session_ticket(hs); | |
| break; | |
| case state13_done: | |
| ret = ssl_hs_ok; | |
| break; | |
| } | |
| if (hs->tls13_state != state) { | |
| ssl_do_info_callback(hs->ssl, SSL_CB_ACCEPT_LOOP, 1); | |
| } | |
| if (ret != ssl_hs_ok) { | |
| return ret; | |
| } | |
| } | |
| return ssl_hs_ok; | |
| } | |
| const char *tls13_server_handshake_state(SSL_HANDSHAKE *hs) { | |
| enum tls13_server_hs_state_t state = | |
| static_cast<enum tls13_server_hs_state_t>(hs->tls13_state); | |
| switch (state) { | |
| case state13_select_parameters: | |
| return "TLS 1.3 server select_parameters"; | |
| case state13_select_session: | |
| return "TLS 1.3 server select_session"; | |
| case state13_send_hello_retry_request: | |
| return "TLS 1.3 server send_hello_retry_request"; | |
| case state13_read_second_client_hello: | |
| return "TLS 1.3 server read_second_client_hello"; | |
| case state13_send_server_hello: | |
| return "TLS 1.3 server send_server_hello"; | |
| case state13_send_server_certificate_verify: | |
| return "TLS 1.3 server send_server_certificate_verify"; | |
| case state13_send_half_rtt_ticket: | |
| return "TLS 1.3 server send_half_rtt_ticket"; | |
| case state13_send_server_finished: | |
| return "TLS 1.3 server send_server_finished"; | |
| case state13_read_second_client_flight: | |
| return "TLS 1.3 server read_second_client_flight"; | |
| case state13_process_end_of_early_data: | |
| return "TLS 1.3 server process_end_of_early_data"; | |
| case state13_read_client_encrypted_extensions: | |
| return "TLS 1.3 server read_client_encrypted_extensions"; | |
| case state13_read_client_certificate: | |
| return "TLS 1.3 server read_client_certificate"; | |
| case state13_read_client_certificate_verify: | |
| return "TLS 1.3 server read_client_certificate_verify"; | |
| case state13_read_channel_id: | |
| return "TLS 1.3 server read_channel_id"; | |
| case state13_read_client_finished: | |
| return "TLS 1.3 server read_client_finished"; | |
| case state13_send_new_session_ticket: | |
| return "TLS 1.3 server send_new_session_ticket"; | |
| case state13_done: | |
| return "TLS 1.3 server done"; | |
| } | |
| return "TLS 1.3 server unknown"; | |
| } | |
| BSSL_NAMESPACE_END |