| /* Copyright 2016 The BoringSSL Authors |
| * |
| * 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 <algorithm> |
| #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 the key_share secret from hints. |
| if (!hs->key_share_ciphertext.CopyFrom(hints->key_share_ciphertext) || |
| !secret.CopyFrom(hints->key_share_secret)) { |
| ssl_send_alert(ssl, SSL3_AL_FATAL, SSL_AD_INTERNAL_ERROR); |
| return false; |
| } |
| } else { |
| ScopedCBB ciphertext; |
| UniquePtr<SSLKeyShare> key_share = SSLKeyShare::Create(group_id); |
| if (!key_share || // |
| !CBB_init(ciphertext.get(), 32) || |
| !key_share->Encap(ciphertext.get(), &secret, &alert, peer_key) || |
| !CBBFinishArray(ciphertext.get(), &hs->key_share_ciphertext)) { |
| 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_ciphertext.CopyFrom(hs->key_share_ciphertext) || |
| !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->s3->version) || // |
| !CBB_flush(out)) { |
| return 0; |
| } |
| |
| return 1; |
| } |
| |
| static const SSL_CIPHER *choose_tls13_cipher( |
| const SSL *ssl, const SSL_CLIENT_HELLO *client_hello) { |
| 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, |
| ssl->config->aes_hw_override |
| ? ssl->config->aes_hw_override_value |
| : EVP_has_aes_hardware(), |
| version, ssl->config->compliance_policy); |
| } |
| |
| 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; |
| } |
| |
| // Rebase the session timestamp so that it is measured from ticket |
| // issuance. |
| ssl_session_rebase_time(ssl, hs->new_session.get()); |
| |
| assert(ssl->session_ctx->num_tickets <= kMaxTickets); |
| bool sent_tickets = false; |
| for (size_t i = 0; i < ssl->session_ctx->num_tickets; 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; |
| // TODO(crbug.com/381113363): Remove the SSL_is_dtls check once we support |
| // 0-RTT for DTLS 1.3. |
| bool enable_early_data = |
| ssl->enable_early_data && |
| (!SSL_is_quic(ssl) || !ssl->config->quic_early_data_context.empty()) && |
| !SSL_is_dtls(ssl); |
| 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_is_quic(ssl) ? 0xffffffff : kMaxEarlyDataAccepted; |
| } |
| |
| static_assert(kMaxTickets < 256, "Too many tickets"); |
| assert(i < 256); |
| 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)) || |
| !tls13_derive_session_psk(session.get(), nonce, SSL_is_dtls(ssl)) || |
| !CBB_add_u16_length_prefixed(&body, &ticket) || |
| !ssl_encrypt_ticket(hs, &ticket, session.get())) { |
| return false; |
| } |
| |
| if (CBB_len(&ticket) == 0) { |
| // The caller decided not to encrypt a ticket. Skip the message. |
| continue; |
| } |
| |
| if (!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; |
| } |
| sent_tickets = true; |
| } |
| |
| *out_sent_tickets = sent_tickets; |
| return true; |
| } |
| |
| static bool check_credential(SSL_HANDSHAKE *hs, const SSL_CREDENTIAL *cred, |
| uint16_t *out_sigalg) { |
| switch (cred->type) { |
| case SSLCredentialType::kX509: |
| break; |
| case SSLCredentialType::kDelegated: |
| // Check that the peer supports the signature over the delegated |
| // credential. |
| if (std::find(hs->peer_sigalgs.begin(), hs->peer_sigalgs.end(), |
| cred->dc_algorithm) == hs->peer_sigalgs.end()) { |
| OPENSSL_PUT_ERROR(SSL, SSL_R_NO_COMMON_SIGNATURE_ALGORITHMS); |
| return false; |
| } |
| break; |
| } |
| |
| // All currently supported credentials require a signature. If |cred| is a |
| // delegated credential, this also checks that the peer supports delegated |
| // credentials and matched |dc_cert_verify_algorithm|. |
| if (!tls1_choose_signature_algorithm(hs, cred, out_sigalg)) { |
| return false; |
| } |
| // Use this credential if it either matches a requested issuer, |
| // or does not require issuer matching. |
| return ssl_credential_matches_requested_issuers(hs, cred); |
| } |
| |
| 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_is_quic(ssl) && 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; |
| } |
| // DTLS 1.3 disables compatibility mode, and even if the client advertised a |
| // session ID (for resumption in DTLS 1.2), the server "MUST NOT echo the |
| // 'legacy_session_id' value from the client" (RFC 9147, section 5) as it |
| // would in a TLS 1.3 handshake. |
| if (!SSL_is_dtls(ssl)) { |
| hs->session_id.CopyFrom( |
| Span(client_hello.session_id, client_hello.session_id_len)); |
| } |
| |
| Array<SSL_CREDENTIAL *> creds; |
| if (!ssl_get_credential_list(hs, &creds)) { |
| return ssl_hs_error; |
| } |
| if (creds.empty()) { |
| OPENSSL_PUT_ERROR(SSL, SSL_R_NO_CERTIFICATE_SET); |
| ssl_send_alert(ssl, SSL3_AL_FATAL, SSL_AD_INTERNAL_ERROR); |
| return ssl_hs_error; |
| } |
| |
| // Select the credential to use. |
| for (SSL_CREDENTIAL *cred : creds) { |
| ERR_clear_error(); |
| uint16_t sigalg; |
| if (check_credential(hs, cred, &sigalg)) { |
| hs->credential = UpRef(cred); |
| hs->signature_algorithm = sigalg; |
| break; |
| } |
| } |
| if (hs->credential == nullptr) { |
| // The error from the last attempt is in the error queue. |
| 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); |
| 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; |
| |
| OPENSSL_timeval now = ssl_ctx_get_current_time(ssl->ctx.get()); |
| |
| // 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 (Span(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 || |
| Span(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_is_quic(ssl)) { |
| 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 |
| ? Span(hs->new_session->secret) |
| : Span(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; |
| 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.data(), |
| hs->session_id.size()) || |
| !CBB_add_u16(&body, SSL_CIPHER_get_protocol_id(hs->new_cipher)) || |
| !CBB_add_u8(&body, 0 /* no compression */) || |
| !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->s3->version) || |
| !CBB_add_u16(&extensions, TLSEXT_TYPE_key_share) || |
| !CBB_add_u16(&extensions, 2 /* length */) || |
| !CBB_add_u16(&extensions, hs->new_session->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, Span(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. |
| uint8_t alert = SSL_AD_DECODE_ERROR; |
| bool unused; |
| if (!ssl_client_hello_decrypt(hs, &alert, &unused, |
| &hs->ech_client_hello_buf, &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, alert); |
| return ssl_hs_error; |
| } |
| |
| // 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_tls13.size() == random.size()) { |
| OPENSSL_memcpy(random.data(), hints->server_random_tls13.data(), |
| random.size()); |
| } else { |
| RAND_bytes(random.data(), random.size()); |
| if (hints && hs->hints_requested && |
| !hints->server_random_tls13.CopyFrom(random)) { |
| return ssl_hs_error; |
| } |
| } |
| |
| uint16_t server_hello_version = TLS1_2_VERSION; |
| if (SSL_is_dtls(ssl)) { |
| server_hello_version = DTLS1_2_VERSION; |
| } |
| 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, server_hello_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.data(), |
| hs->session_id.size()) || |
| !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 = |
| Span(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->key_share_ciphertext.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 (!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, |
| Span(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_is_quic(ssl) && !hs->transcript.Update(kEndOfEarlyData)) { |
| OPENSSL_PUT_ERROR(SSL, ERR_R_INTERNAL_ERROR); |
| return ssl_hs_error; |
| } |
| |
| size_t finished_len; |
| hs->expected_client_finished.Resize(hs->transcript.DigestLen()); |
| 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(crbug.com/381113363): Don't use half-RTT tickets with DTLS 1.3. |
| // TODO(crbug.com/376939532): Perhaps don't use half-RTT tickets at all. |
| 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 bool uses_end_of_early_data(const SSL *ssl) { |
| // DTLS and QUIC omit the EndOfEarlyData message. See RFC 9001, section 8.3, |
| // and RFC 9147, section 5.6. |
| return !SSL_is_quic(ssl) && !SSL_is_dtls(ssl); |
| } |
| |
| 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; |
| } |
| |
| // If the EndOfEarlyData message is not used, switch to |
| // client_handshake_secret before the early return. |
| if (!uses_end_of_early_data(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_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 (uses_end_of_early_data(ssl)) { |
| // 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; |
| } |
| |
| uint16_t extension_type = TLSEXT_TYPE_application_settings_old; |
| if (hs->config->alps_use_new_codepoint) { |
| extension_type = TLSEXT_TYPE_application_settings; |
| } |
| SSLExtension application_settings(extension_type); |
| 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); |
| if (SSL_is_dtls(ssl)) { |
| ssl->method->schedule_ack(ssl); |
| return ssl_hs_flush; |
| } |
| return ssl_hs_ok; |
| } |
| |
| static enum ssl_hs_wait_t do_send_new_session_ticket(SSL_HANDSHAKE *hs) { |
| SSL *const ssl = hs->ssl; |
| bool sent_tickets; |
| if (!add_new_session_tickets(hs, &sent_tickets)) { |
| return ssl_hs_error; |
| } |
| |
| hs->tls13_state = state13_done; |
| // In QUIC and DTLS, we can flush the ticket to the transport immediately. In |
| // TLS over TCP-like transports, we defer until the server performs a write. |
| // This prevents 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. |
| bool should_flush = sent_tickets && (SSL_is_dtls(ssl) || SSL_is_quic(ssl)); |
| return should_flush ? ssl_hs_flush : 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 |
