--- /dev/null
+/* Copyright (c) 2016, Google Inc.
+ *
+ * Permission to use, copy, modify, and/or distribute this software for any
+ * purpose with or without fee is hereby granted, provided that the above
+ * copyright notice and this permission notice appear in all copies.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
+ * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
+ * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY
+ * SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
+ * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN ACTION
+ * OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF OR IN
+ * CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE. */
+
+#include <openssl/ssl.h>
+
+#include <assert.h>
+#include <limits.h>
+#include <string.h>
+
+#include <utility>
+
+#include <openssl/bytestring.h>
+#include <openssl/digest.h>
+#include <openssl/err.h>
+#include <openssl/mem.h>
+#include <openssl/stack.h>
+
+#include "../crypto/internal.h"
+#include "internal.h"
+
+
+namespace bssl {
+
+enum client_hs_state_t {
+ state_read_hello_retry_request = 0,
+ state_send_second_client_hello,
+ state_read_server_hello,
+ state_read_encrypted_extensions,
+ state_read_certificate_request,
+ state_read_server_certificate,
+ state_read_server_certificate_verify,
+ state_read_server_finished,
+ state_send_end_of_early_data,
+ state_send_client_certificate,
+ state_send_client_certificate_verify,
+ state_complete_second_flight,
+ state_done,
+};
+
+static const uint8_t kZeroes[EVP_MAX_MD_SIZE] = {0};
+
+static enum ssl_hs_wait_t do_read_hello_retry_request(SSL_HANDSHAKE *hs) {
+ SSL *const ssl = hs->ssl;
+ assert(ssl->s3->have_version);
+ SSLMessage msg;
+ if (!ssl->method->get_message(ssl, &msg)) {
+ return ssl_hs_read_message;
+ }
+
+ // Queue up a ChangeCipherSpec for whenever we next send something. This
+ // will be before the second ClientHello. If we offered early data, this was
+ // already done.
+ if (!hs->early_data_offered &&
+ !ssl->method->add_change_cipher_spec(ssl)) {
+ return ssl_hs_error;
+ }
+
+ if (!ssl_check_message_type(ssl, msg, SSL3_MT_SERVER_HELLO)) {
+ return ssl_hs_error;
+ }
+
+ CBS body = msg.body, extensions, server_random, session_id;
+ uint16_t server_version, cipher_suite;
+ uint8_t compression_method;
+ if (!CBS_get_u16(&body, &server_version) ||
+ !CBS_get_bytes(&body, &server_random, SSL3_RANDOM_SIZE) ||
+ !CBS_get_u8_length_prefixed(&body, &session_id) ||
+ !CBS_mem_equal(&session_id, hs->session_id, hs->session_id_len) ||
+ !CBS_get_u16(&body, &cipher_suite) ||
+ !CBS_get_u8(&body, &compression_method) ||
+ compression_method != 0 ||
+ !CBS_get_u16_length_prefixed(&body, &extensions) ||
+ CBS_len(&extensions) == 0 ||
+ CBS_len(&body) != 0) {
+ OPENSSL_PUT_ERROR(SSL, SSL_R_DECODE_ERROR);
+ ssl_send_alert(ssl, SSL3_AL_FATAL, SSL_AD_DECODE_ERROR);
+ return ssl_hs_error;
+ }
+
+ if (!CBS_mem_equal(&server_random, kHelloRetryRequest, SSL3_RANDOM_SIZE)) {
+ hs->tls13_state = state_read_server_hello;
+ return ssl_hs_ok;
+ }
+
+ const SSL_CIPHER *cipher = SSL_get_cipher_by_value(cipher_suite);
+ // Check if the cipher is a TLS 1.3 cipher.
+ if (cipher == NULL ||
+ SSL_CIPHER_get_min_version(cipher) > ssl_protocol_version(ssl) ||
+ SSL_CIPHER_get_max_version(cipher) < ssl_protocol_version(ssl)) {
+ OPENSSL_PUT_ERROR(SSL, SSL_R_WRONG_CIPHER_RETURNED);
+ ssl_send_alert(ssl, SSL3_AL_FATAL, SSL_AD_ILLEGAL_PARAMETER);
+ return ssl_hs_error;
+ }
+
+ hs->new_cipher = cipher;
+
+ if (!hs->transcript.InitHash(ssl_protocol_version(ssl), hs->new_cipher) ||
+ !hs->transcript.UpdateForHelloRetryRequest()) {
+ return ssl_hs_error;
+ }
+
+
+ bool have_cookie, have_key_share, have_supported_versions;
+ CBS cookie, key_share, supported_versions;
+ SSL_EXTENSION_TYPE ext_types[] = {
+ {TLSEXT_TYPE_key_share, &have_key_share, &key_share},
+ {TLSEXT_TYPE_cookie, &have_cookie, &cookie},
+ {TLSEXT_TYPE_supported_versions, &have_supported_versions,
+ &supported_versions},
+ };
+
+ uint8_t alert = SSL_AD_DECODE_ERROR;
+ if (!ssl_parse_extensions(&extensions, &alert, ext_types,
+ OPENSSL_ARRAY_SIZE(ext_types),
+ 0 /* reject unknown */)) {
+ ssl_send_alert(ssl, SSL3_AL_FATAL, alert);
+ return ssl_hs_error;
+ }
+
+ if (!have_cookie && !have_key_share) {
+ OPENSSL_PUT_ERROR(SSL, SSL_R_EMPTY_HELLO_RETRY_REQUEST);
+ ssl_send_alert(ssl, SSL3_AL_FATAL, SSL_AD_ILLEGAL_PARAMETER);
+ return ssl_hs_error;
+ }
+ if (have_cookie) {
+ CBS cookie_value;
+ if (!CBS_get_u16_length_prefixed(&cookie, &cookie_value) ||
+ CBS_len(&cookie_value) == 0 ||
+ CBS_len(&cookie) != 0) {
+ OPENSSL_PUT_ERROR(SSL, SSL_R_DECODE_ERROR);
+ ssl_send_alert(ssl, SSL3_AL_FATAL, SSL_AD_DECODE_ERROR);
+ return ssl_hs_error;
+ }
+
+ if (!hs->cookie.CopyFrom(cookie_value)) {
+ return ssl_hs_error;
+ }
+ }
+
+ if (have_key_share) {
+ uint16_t group_id;
+ if (!CBS_get_u16(&key_share, &group_id) || CBS_len(&key_share) != 0) {
+ OPENSSL_PUT_ERROR(SSL, SSL_R_DECODE_ERROR);
+ ssl_send_alert(ssl, SSL3_AL_FATAL, SSL_AD_DECODE_ERROR);
+ return ssl_hs_error;
+ }
+
+ // The group must be supported.
+ if (!tls1_check_group_id(ssl, group_id)) {
+ ssl_send_alert(ssl, SSL3_AL_FATAL, SSL_AD_ILLEGAL_PARAMETER);
+ OPENSSL_PUT_ERROR(SSL, SSL_R_WRONG_CURVE);
+ return ssl_hs_error;
+ }
+
+ // Check that the HelloRetryRequest does not request the key share that
+ // was provided in the initial ClientHello.
+ if (hs->key_share->GroupID() == group_id) {
+ ssl_send_alert(ssl, SSL3_AL_FATAL, SSL_AD_ILLEGAL_PARAMETER);
+ OPENSSL_PUT_ERROR(SSL, SSL_R_WRONG_CURVE);
+ return ssl_hs_error;
+ }
+
+ hs->key_share.reset();
+ hs->retry_group = group_id;
+ }
+
+ if (!ssl_hash_message(hs, msg)) {
+ return ssl_hs_error;
+ }
+
+ ssl->method->next_message(ssl);
+ hs->received_hello_retry_request = true;
+ hs->tls13_state = state_send_second_client_hello;
+ // 0-RTT is rejected if we receive a HelloRetryRequest.
+ if (hs->in_early_data) {
+ return ssl_hs_early_data_rejected;
+ }
+ return ssl_hs_ok;
+}
+
+static enum ssl_hs_wait_t do_send_second_client_hello(SSL_HANDSHAKE *hs) {
+ SSL *const ssl = hs->ssl;
+ // Restore the null cipher. We may have switched due to 0-RTT.
+ bssl::UniquePtr<SSLAEADContext> null_ctx =
+ SSLAEADContext::CreateNullCipher(SSL_is_dtls(ssl));
+ if (!null_ctx ||
+ !ssl->method->set_write_state(ssl, std::move(null_ctx))) {
+ return ssl_hs_error;
+ }
+
+ ssl->s3->aead_write_ctx->SetVersionIfNullCipher(ssl->version);
+
+ if (!ssl_write_client_hello(hs)) {
+ return ssl_hs_error;
+ }
+
+ hs->tls13_state = state_read_server_hello;
+ return ssl_hs_flush;
+}
+
+static enum ssl_hs_wait_t do_read_server_hello(SSL_HANDSHAKE *hs) {
+ SSL *const ssl = hs->ssl;
+ SSLMessage msg;
+ if (!ssl->method->get_message(ssl, &msg)) {
+ return ssl_hs_read_message;
+ }
+ if (!ssl_check_message_type(ssl, msg, SSL3_MT_SERVER_HELLO)) {
+ return ssl_hs_error;
+ }
+
+ CBS body = msg.body, server_random, session_id, extensions;
+ uint16_t server_version;
+ uint16_t cipher_suite;
+ uint8_t compression_method;
+ if (!CBS_get_u16(&body, &server_version) ||
+ !CBS_get_bytes(&body, &server_random, SSL3_RANDOM_SIZE) ||
+ !CBS_get_u8_length_prefixed(&body, &session_id) ||
+ !CBS_mem_equal(&session_id, hs->session_id, hs->session_id_len) ||
+ !CBS_get_u16(&body, &cipher_suite) ||
+ !CBS_get_u8(&body, &compression_method) ||
+ compression_method != 0 ||
+ !CBS_get_u16_length_prefixed(&body, &extensions) ||
+ CBS_len(&body) != 0) {
+ ssl_send_alert(ssl, SSL3_AL_FATAL, SSL_AD_DECODE_ERROR);
+ OPENSSL_PUT_ERROR(SSL, SSL_R_DECODE_ERROR);
+ return ssl_hs_error;
+ }
+
+ if (server_version != TLS1_2_VERSION) {
+ ssl_send_alert(ssl, SSL3_AL_FATAL, SSL_AD_DECODE_ERROR);
+ OPENSSL_PUT_ERROR(SSL, SSL_R_WRONG_VERSION_NUMBER);
+ return ssl_hs_error;
+ }
+
+ // Forbid a second HelloRetryRequest.
+ if (CBS_mem_equal(&server_random, kHelloRetryRequest, SSL3_RANDOM_SIZE)) {
+ ssl_send_alert(ssl, SSL3_AL_FATAL, SSL_AD_UNEXPECTED_MESSAGE);
+ OPENSSL_PUT_ERROR(SSL, SSL_R_UNEXPECTED_MESSAGE);
+ return ssl_hs_error;
+ }
+
+ OPENSSL_memcpy(ssl->s3->server_random, CBS_data(&server_random),
+ SSL3_RANDOM_SIZE);
+
+ // Check if the cipher is a TLS 1.3 cipher.
+ const SSL_CIPHER *cipher = SSL_get_cipher_by_value(cipher_suite);
+ if (cipher == nullptr ||
+ SSL_CIPHER_get_min_version(cipher) > ssl_protocol_version(ssl) ||
+ SSL_CIPHER_get_max_version(cipher) < ssl_protocol_version(ssl)) {
+ OPENSSL_PUT_ERROR(SSL, SSL_R_WRONG_CIPHER_RETURNED);
+ ssl_send_alert(ssl, SSL3_AL_FATAL, SSL_AD_ILLEGAL_PARAMETER);
+ return ssl_hs_error;
+ }
+
+ // Check that the cipher matches the one in the HelloRetryRequest.
+ if (hs->received_hello_retry_request &&
+ hs->new_cipher != cipher) {
+ OPENSSL_PUT_ERROR(SSL, SSL_R_WRONG_CIPHER_RETURNED);
+ ssl_send_alert(ssl, SSL3_AL_FATAL, SSL_AD_ILLEGAL_PARAMETER);
+ return ssl_hs_error;
+ }
+
+ // Parse out the extensions.
+ bool have_key_share = false, have_pre_shared_key = false,
+ have_supported_versions = false;
+ CBS key_share, pre_shared_key, supported_versions;
+ SSL_EXTENSION_TYPE ext_types[] = {
+ {TLSEXT_TYPE_key_share, &have_key_share, &key_share},
+ {TLSEXT_TYPE_pre_shared_key, &have_pre_shared_key, &pre_shared_key},
+ {TLSEXT_TYPE_supported_versions, &have_supported_versions,
+ &supported_versions},
+ };
+
+ uint8_t alert = SSL_AD_DECODE_ERROR;
+ if (!ssl_parse_extensions(&extensions, &alert, ext_types,
+ OPENSSL_ARRAY_SIZE(ext_types),
+ 0 /* reject unknown */)) {
+ ssl_send_alert(ssl, SSL3_AL_FATAL, alert);
+ return ssl_hs_error;
+ }
+
+ alert = SSL_AD_DECODE_ERROR;
+ if (have_pre_shared_key) {
+ if (ssl->session == NULL) {
+ OPENSSL_PUT_ERROR(SSL, SSL_R_UNEXPECTED_EXTENSION);
+ ssl_send_alert(ssl, SSL3_AL_FATAL, SSL_AD_UNSUPPORTED_EXTENSION);
+ return ssl_hs_error;
+ }
+
+ if (!ssl_ext_pre_shared_key_parse_serverhello(hs, &alert,
+ &pre_shared_key)) {
+ ssl_send_alert(ssl, SSL3_AL_FATAL, alert);
+ return ssl_hs_error;
+ }
+
+ if (ssl->session->ssl_version != ssl->version) {
+ OPENSSL_PUT_ERROR(SSL, SSL_R_OLD_SESSION_VERSION_NOT_RETURNED);
+ ssl_send_alert(ssl, SSL3_AL_FATAL, SSL_AD_ILLEGAL_PARAMETER);
+ return ssl_hs_error;
+ }
+
+ if (ssl->session->cipher->algorithm_prf != cipher->algorithm_prf) {
+ OPENSSL_PUT_ERROR(SSL, SSL_R_OLD_SESSION_PRF_HASH_MISMATCH);
+ ssl_send_alert(ssl, SSL3_AL_FATAL, SSL_AD_ILLEGAL_PARAMETER);
+ return ssl_hs_error;
+ }
+
+ if (!ssl_session_is_context_valid(ssl, ssl->session)) {
+ // This is actually a client application bug.
+ OPENSSL_PUT_ERROR(SSL,
+ SSL_R_ATTEMPT_TO_REUSE_SESSION_IN_DIFFERENT_CONTEXT);
+ ssl_send_alert(ssl, SSL3_AL_FATAL, SSL_AD_ILLEGAL_PARAMETER);
+ return ssl_hs_error;
+ }
+
+ ssl->s3->session_reused = true;
+ // Only authentication information carries over in TLS 1.3.
+ hs->new_session = SSL_SESSION_dup(ssl->session, SSL_SESSION_DUP_AUTH_ONLY);
+ if (!hs->new_session) {
+ ssl_send_alert(ssl, SSL3_AL_FATAL, SSL_AD_INTERNAL_ERROR);
+ return ssl_hs_error;
+ }
+ ssl_set_session(ssl, NULL);
+
+ // Resumption incorporates fresh key material, so refresh the timeout.
+ ssl_session_renew_timeout(ssl, hs->new_session.get(),
+ ssl->session_ctx->session_psk_dhe_timeout);
+ } else if (!ssl_get_new_session(hs, 0)) {
+ ssl_send_alert(ssl, SSL3_AL_FATAL, SSL_AD_INTERNAL_ERROR);
+ return ssl_hs_error;
+ }
+
+ hs->new_session->cipher = cipher;
+ hs->new_cipher = cipher;
+
+ size_t hash_len =
+ EVP_MD_size(ssl_get_handshake_digest(ssl_protocol_version(ssl), cipher));
+
+ // Set up the key schedule and incorporate the PSK into the running secret.
+ if (ssl->s3->session_reused) {
+ if (!tls13_init_key_schedule(hs, hs->new_session->master_key,
+ hs->new_session->master_key_length)) {
+ return ssl_hs_error;
+ }
+ } else if (!tls13_init_key_schedule(hs, kZeroes, hash_len)) {
+ return ssl_hs_error;
+ }
+
+ if (!have_key_share) {
+ // We do not support psk_ke and thus always require a key share.
+ OPENSSL_PUT_ERROR(SSL, SSL_R_MISSING_KEY_SHARE);
+ ssl_send_alert(ssl, SSL3_AL_FATAL, SSL_AD_MISSING_EXTENSION);
+ return ssl_hs_error;
+ }
+
+ // Resolve ECDHE and incorporate it into the secret.
+ Array<uint8_t> dhe_secret;
+ alert = SSL_AD_DECODE_ERROR;
+ if (!ssl_ext_key_share_parse_serverhello(hs, &dhe_secret, &alert,
+ &key_share)) {
+ ssl_send_alert(ssl, SSL3_AL_FATAL, alert);
+ return ssl_hs_error;
+ }
+
+ if (!tls13_advance_key_schedule(hs, dhe_secret.data(), dhe_secret.size()) ||
+ !ssl_hash_message(hs, msg) ||
+ !tls13_derive_handshake_secrets(hs) ||
+ !tls13_set_traffic_key(ssl, evp_aead_open, hs->server_handshake_secret,
+ hs->hash_len)) {
+ return ssl_hs_error;
+ }
+
+ if (!hs->early_data_offered) {
+ // If not sending early data, set client traffic keys now so that alerts are
+ // encrypted.
+ if (!tls13_set_traffic_key(ssl, evp_aead_seal, hs->client_handshake_secret,
+ hs->hash_len)) {
+ return ssl_hs_error;
+ }
+ }
+
+ ssl->method->next_message(ssl);
+ hs->tls13_state = state_read_encrypted_extensions;
+ return ssl_hs_ok;
+}
+
+static enum ssl_hs_wait_t do_read_encrypted_extensions(SSL_HANDSHAKE *hs) {
+ SSL *const ssl = hs->ssl;
+ SSLMessage msg;
+ if (!ssl->method->get_message(ssl, &msg)) {
+ return ssl_hs_read_message;
+ }
+ if (!ssl_check_message_type(ssl, msg, SSL3_MT_ENCRYPTED_EXTENSIONS)) {
+ return ssl_hs_error;
+ }
+
+ CBS body = msg.body;
+ if (!ssl_parse_serverhello_tlsext(hs, &body)) {
+ OPENSSL_PUT_ERROR(SSL, SSL_R_PARSE_TLSEXT);
+ return ssl_hs_error;
+ }
+ if (CBS_len(&body) != 0) {
+ OPENSSL_PUT_ERROR(SSL, SSL_R_DECODE_ERROR);
+ ssl_send_alert(ssl, SSL3_AL_FATAL, SSL_AD_DECODE_ERROR);
+ return ssl_hs_error;
+ }
+
+ // Store the negotiated ALPN in the session.
+ if (!ssl->s3->alpn_selected.empty()) {
+ hs->new_session->early_alpn = (uint8_t *)BUF_memdup(
+ ssl->s3->alpn_selected.data(), ssl->s3->alpn_selected.size());
+ if (hs->new_session->early_alpn == NULL) {
+ ssl_send_alert(ssl, SSL3_AL_FATAL, SSL_AD_INTERNAL_ERROR);
+ return ssl_hs_error;
+ }
+ hs->new_session->early_alpn_len = ssl->s3->alpn_selected.size();
+ }
+
+ if (ssl->s3->early_data_accepted) {
+ if (hs->early_session->cipher != hs->new_session->cipher ||
+ MakeConstSpan(hs->early_session->early_alpn,
+ hs->early_session->early_alpn_len) !=
+ ssl->s3->alpn_selected) {
+ OPENSSL_PUT_ERROR(SSL, SSL_R_ALPN_MISMATCH_ON_EARLY_DATA);
+ return ssl_hs_error;
+ }
+ if (ssl->s3->tlsext_channel_id_valid || hs->received_custom_extension ||
+ ssl->token_binding_negotiated) {
+ OPENSSL_PUT_ERROR(SSL, SSL_R_UNEXPECTED_EXTENSION_ON_EARLY_DATA);
+ return ssl_hs_error;
+ }
+ }
+
+ if (!ssl_hash_message(hs, msg)) {
+ return ssl_hs_error;
+ }
+
+ ssl->method->next_message(ssl);
+ hs->tls13_state = state_read_certificate_request;
+ if (hs->in_early_data && !ssl->s3->early_data_accepted) {
+ return ssl_hs_early_data_rejected;
+ }
+ return ssl_hs_ok;
+}
+
+static enum ssl_hs_wait_t do_read_certificate_request(SSL_HANDSHAKE *hs) {
+ SSL *const ssl = hs->ssl;
+ // CertificateRequest may only be sent in non-resumption handshakes.
+ if (ssl->s3->session_reused) {
+ hs->tls13_state = state_read_server_finished;
+ return ssl_hs_ok;
+ }
+
+ SSLMessage msg;
+ if (!ssl->method->get_message(ssl, &msg)) {
+ return ssl_hs_read_message;
+ }
+
+ // CertificateRequest is optional.
+ if (msg.type != SSL3_MT_CERTIFICATE_REQUEST) {
+ hs->tls13_state = state_read_server_certificate;
+ return ssl_hs_ok;
+ }
+
+
+ bool have_sigalgs = false, have_ca = false;
+ CBS sigalgs, ca;
+ const SSL_EXTENSION_TYPE ext_types[] = {
+ {TLSEXT_TYPE_signature_algorithms, &have_sigalgs, &sigalgs},
+ {TLSEXT_TYPE_certificate_authorities, &have_ca, &ca},
+ };
+
+ CBS body = msg.body, context, extensions, supported_signature_algorithms;
+ uint8_t alert = SSL_AD_DECODE_ERROR;
+ if (!CBS_get_u8_length_prefixed(&body, &context) ||
+ // The request context is always empty during the handshake.
+ CBS_len(&context) != 0 ||
+ !CBS_get_u16_length_prefixed(&body, &extensions) ||
+ CBS_len(&body) != 0 ||
+ !ssl_parse_extensions(&extensions, &alert, ext_types,
+ OPENSSL_ARRAY_SIZE(ext_types),
+ 1 /* accept unknown */) ||
+ (have_ca && CBS_len(&ca) == 0) ||
+ !have_sigalgs ||
+ !CBS_get_u16_length_prefixed(&sigalgs,
+ &supported_signature_algorithms) ||
+ CBS_len(&supported_signature_algorithms) == 0 ||
+ !tls1_parse_peer_sigalgs(hs, &supported_signature_algorithms)) {
+ ssl_send_alert(ssl, SSL3_AL_FATAL, alert);
+ OPENSSL_PUT_ERROR(SSL, SSL_R_DECODE_ERROR);
+ return ssl_hs_error;
+ }
+
+ if (have_ca) {
+ hs->ca_names = ssl_parse_client_CA_list(ssl, &alert, &ca);
+ if (!hs->ca_names) {
+ ssl_send_alert(ssl, SSL3_AL_FATAL, alert);
+ return ssl_hs_error;
+ }
+ } else {
+ hs->ca_names.reset(sk_CRYPTO_BUFFER_new_null());
+ if (!hs->ca_names) {
+ OPENSSL_PUT_ERROR(SSL, ERR_R_MALLOC_FAILURE);
+ ssl_send_alert(ssl, SSL3_AL_FATAL, SSL_AD_INTERNAL_ERROR);
+ return ssl_hs_error;
+ }
+ }
+
+ hs->cert_request = true;
+ ssl->ctx->x509_method->hs_flush_cached_ca_names(hs);
+
+ if (!ssl_hash_message(hs, msg)) {
+ return ssl_hs_error;
+ }
+
+ ssl->method->next_message(ssl);
+ hs->tls13_state = state_read_server_certificate;
+ return ssl_hs_ok;
+}
+
+static enum ssl_hs_wait_t do_read_server_certificate(SSL_HANDSHAKE *hs) {
+ SSL *const ssl = hs->ssl;
+ SSLMessage msg;
+ if (!ssl->method->get_message(ssl, &msg)) {
+ return ssl_hs_read_message;
+ }
+ if (!ssl_check_message_type(ssl, msg, SSL3_MT_CERTIFICATE) ||
+ !tls13_process_certificate(hs, msg, 0 /* certificate required */) ||
+ !ssl_hash_message(hs, msg)) {
+ return ssl_hs_error;
+ }
+
+ ssl->method->next_message(ssl);
+ hs->tls13_state = state_read_server_certificate_verify;
+ return ssl_hs_ok;
+}
+
+static enum ssl_hs_wait_t do_read_server_certificate_verify(
+ SSL_HANDSHAKE *hs) {
+ SSL *const ssl = hs->ssl;
+ SSLMessage msg;
+ if (!ssl->method->get_message(ssl, &msg)) {
+ return ssl_hs_read_message;
+ }
+ switch (ssl_verify_peer_cert(hs)) {
+ case ssl_verify_ok:
+ break;
+ case ssl_verify_invalid:
+ return ssl_hs_error;
+ case ssl_verify_retry:
+ hs->tls13_state = state_read_server_certificate_verify;
+ return ssl_hs_certificate_verify;
+ }
+
+ if (!ssl_check_message_type(ssl, msg, SSL3_MT_CERTIFICATE_VERIFY) ||
+ !tls13_process_certificate_verify(hs, msg) ||
+ !ssl_hash_message(hs, msg)) {
+ return ssl_hs_error;
+ }
+
+ ssl->method->next_message(ssl);
+ hs->tls13_state = state_read_server_finished;
+ return ssl_hs_ok;
+}
+
+static enum ssl_hs_wait_t do_read_server_finished(SSL_HANDSHAKE *hs) {
+ SSL *const ssl = hs->ssl;
+ SSLMessage msg;
+ if (!ssl->method->get_message(ssl, &msg)) {
+ return ssl_hs_read_message;
+ }
+ if (!ssl_check_message_type(ssl, msg, SSL3_MT_FINISHED) ||
+ !tls13_process_finished(hs, msg, 0 /* don't use saved value */) ||
+ !ssl_hash_message(hs, msg) ||
+ // Update the secret to the master secret and derive traffic keys.
+ !tls13_advance_key_schedule(hs, kZeroes, hs->hash_len) ||
+ !tls13_derive_application_secrets(hs)) {
+ return ssl_hs_error;
+ }
+
+ ssl->method->next_message(ssl);
+ hs->tls13_state = state_send_end_of_early_data;
+ return ssl_hs_ok;
+}
+
+static enum ssl_hs_wait_t do_send_end_of_early_data(SSL_HANDSHAKE *hs) {
+ SSL *const ssl = hs->ssl;
+
+ if (ssl->s3->early_data_accepted) {
+ hs->can_early_write = false;
+ ScopedCBB cbb;
+ CBB body;
+ if (!ssl->method->init_message(ssl, cbb.get(), &body,
+ SSL3_MT_END_OF_EARLY_DATA) ||
+ !ssl_add_message_cbb(ssl, cbb.get())) {
+ return ssl_hs_error;
+ }
+ }
+
+ if (hs->early_data_offered) {
+ if (!tls13_set_traffic_key(ssl, evp_aead_seal, hs->client_handshake_secret,
+ hs->hash_len)) {
+ return ssl_hs_error;
+ }
+ }
+
+ hs->tls13_state = state_send_client_certificate;
+ return ssl_hs_ok;
+}
+
+static enum ssl_hs_wait_t do_send_client_certificate(SSL_HANDSHAKE *hs) {
+ SSL *const ssl = hs->ssl;
+
+ // The peer didn't request a certificate.
+ if (!hs->cert_request) {
+ hs->tls13_state = state_complete_second_flight;
+ return ssl_hs_ok;
+ }
+
+ // Call cert_cb to update the certificate.
+ if (ssl->cert->cert_cb != NULL) {
+ int rv = ssl->cert->cert_cb(ssl, ssl->cert->cert_cb_arg);
+ if (rv == 0) {
+ ssl_send_alert(ssl, SSL3_AL_FATAL, SSL_AD_INTERNAL_ERROR);
+ OPENSSL_PUT_ERROR(SSL, SSL_R_CERT_CB_ERROR);
+ return ssl_hs_error;
+ }
+ if (rv < 0) {
+ hs->tls13_state = state_send_client_certificate;
+ return ssl_hs_x509_lookup;
+ }
+ }
+
+ if (!ssl_on_certificate_selected(hs) ||
+ !tls13_add_certificate(hs)) {
+ return ssl_hs_error;
+ }
+
+ hs->tls13_state = state_send_client_certificate_verify;
+ return ssl_hs_ok;
+}
+
+static enum ssl_hs_wait_t do_send_client_certificate_verify(SSL_HANDSHAKE *hs) {
+ SSL *const ssl = hs->ssl;
+ // Don't send CertificateVerify if there is no certificate.
+ if (!ssl_has_certificate(ssl)) {
+ hs->tls13_state = state_complete_second_flight;
+ return ssl_hs_ok;
+ }
+
+ switch (tls13_add_certificate_verify(hs)) {
+ case ssl_private_key_success:
+ hs->tls13_state = state_complete_second_flight;
+ return ssl_hs_ok;
+
+ case ssl_private_key_retry:
+ hs->tls13_state = state_send_client_certificate_verify;
+ return ssl_hs_private_key_operation;
+
+ case ssl_private_key_failure:
+ return ssl_hs_error;
+ }
+
+ assert(0);
+ return ssl_hs_error;
+}
+
+static enum ssl_hs_wait_t do_complete_second_flight(SSL_HANDSHAKE *hs) {
+ SSL *const ssl = hs->ssl;
+
+ // Send a Channel ID assertion if necessary.
+ if (ssl->s3->tlsext_channel_id_valid) {
+ if (!ssl_do_channel_id_callback(ssl)) {
+ hs->tls13_state = state_complete_second_flight;
+ return ssl_hs_error;
+ }
+
+ if (ssl->tlsext_channel_id_private == NULL) {
+ return ssl_hs_channel_id_lookup;
+ }
+
+ ScopedCBB cbb;
+ CBB body;
+ if (!ssl->method->init_message(ssl, cbb.get(), &body, SSL3_MT_CHANNEL_ID) ||
+ !tls1_write_channel_id(hs, &body) ||
+ !ssl_add_message_cbb(ssl, cbb.get())) {
+ return ssl_hs_error;
+ }
+ }
+
+ // Send a Finished message.
+ if (!tls13_add_finished(hs)) {
+ return ssl_hs_error;
+ }
+
+ // Derive the final keys and enable them.
+ if (!tls13_set_traffic_key(ssl, evp_aead_open, hs->server_traffic_secret_0,
+ hs->hash_len) ||
+ !tls13_set_traffic_key(ssl, evp_aead_seal, hs->client_traffic_secret_0,
+ hs->hash_len) ||
+ !tls13_derive_resumption_secret(hs)) {
+ return ssl_hs_error;
+ }
+
+ hs->tls13_state = state_done;
+ return ssl_hs_flush;
+}
+
+enum ssl_hs_wait_t tls13_client_handshake(SSL_HANDSHAKE *hs) {
+ while (hs->tls13_state != state_done) {
+ enum ssl_hs_wait_t ret = ssl_hs_error;
+ enum client_hs_state_t state =
+ static_cast<enum client_hs_state_t>(hs->tls13_state);
+ switch (state) {
+ case state_read_hello_retry_request:
+ ret = do_read_hello_retry_request(hs);
+ break;
+ case state_send_second_client_hello:
+ ret = do_send_second_client_hello(hs);
+ break;
+ case state_read_server_hello:
+ ret = do_read_server_hello(hs);
+ break;
+ case state_read_encrypted_extensions:
+ ret = do_read_encrypted_extensions(hs);
+ break;
+ case state_read_certificate_request:
+ ret = do_read_certificate_request(hs);
+ break;
+ case state_read_server_certificate:
+ ret = do_read_server_certificate(hs);
+ break;
+ case state_read_server_certificate_verify:
+ ret = do_read_server_certificate_verify(hs);
+ break;
+ case state_read_server_finished:
+ ret = do_read_server_finished(hs);
+ break;
+ case state_send_end_of_early_data:
+ ret = do_send_end_of_early_data(hs);
+ break;
+ case state_send_client_certificate:
+ ret = do_send_client_certificate(hs);
+ break;
+ case state_send_client_certificate_verify:
+ ret = do_send_client_certificate_verify(hs);
+ break;
+ case state_complete_second_flight:
+ ret = do_complete_second_flight(hs);
+ break;
+ case state_done:
+ ret = ssl_hs_ok;
+ break;
+ }
+
+ if (hs->tls13_state != state) {
+ ssl_do_info_callback(hs->ssl, SSL_CB_CONNECT_LOOP, 1);
+ }
+
+ if (ret != ssl_hs_ok) {
+ return ret;
+ }
+ }
+
+ return ssl_hs_ok;
+}
+
+const char *tls13_client_handshake_state(SSL_HANDSHAKE *hs) {
+ enum client_hs_state_t state =
+ static_cast<enum client_hs_state_t>(hs->tls13_state);
+ switch (state) {
+ case state_read_hello_retry_request:
+ return "TLS 1.3 client read_hello_retry_request";
+ case state_send_second_client_hello:
+ return "TLS 1.3 client send_second_client_hello";
+ case state_read_server_hello:
+ return "TLS 1.3 client read_server_hello";
+ case state_read_encrypted_extensions:
+ return "TLS 1.3 client read_encrypted_extensions";
+ case state_read_certificate_request:
+ return "TLS 1.3 client read_certificate_request";
+ case state_read_server_certificate:
+ return "TLS 1.3 client read_server_certificate";
+ case state_read_server_certificate_verify:
+ return "TLS 1.3 client read_server_certificate_verify";
+ case state_read_server_finished:
+ return "TLS 1.3 client read_server_finished";
+ case state_send_end_of_early_data:
+ return "TLS 1.3 client send_end_of_early_data";
+ case state_send_client_certificate:
+ return "TLS 1.3 client send_client_certificate";
+ case state_send_client_certificate_verify:
+ return "TLS 1.3 client send_client_certificate_verify";
+ case state_complete_second_flight:
+ return "TLS 1.3 client complete_second_flight";
+ case state_done:
+ return "TLS 1.3 client done";
+ }
+
+ return "TLS 1.3 client unknown";
+}
+
+int tls13_process_new_session_ticket(SSL *ssl, const SSLMessage &msg) {
+ if (ssl->s3->write_shutdown != ssl_shutdown_none) {
+ // Ignore tickets on shutdown. Callers tend to indiscriminately call
+ // |SSL_shutdown| before destroying an |SSL|, at which point calling the new
+ // session callback may be confusing.
+ return 1;
+ }
+
+ UniquePtr<SSL_SESSION> session = SSL_SESSION_dup(
+ ssl->s3->established_session.get(), SSL_SESSION_INCLUDE_NONAUTH);
+ if (!session) {
+ return 0;
+ }
+
+ ssl_session_rebase_time(ssl, session.get());
+
+ uint32_t server_timeout;
+ CBS body = msg.body, ticket_nonce, ticket, extensions;
+ if (!CBS_get_u32(&body, &server_timeout) ||
+ !CBS_get_u32(&body, &session->ticket_age_add) ||
+ !CBS_get_u8_length_prefixed(&body, &ticket_nonce) ||
+ !CBS_get_u16_length_prefixed(&body, &ticket) ||
+ !CBS_stow(&ticket, &session->tlsext_tick, &session->tlsext_ticklen) ||
+ !CBS_get_u16_length_prefixed(&body, &extensions) ||
+ CBS_len(&body) != 0) {
+ ssl_send_alert(ssl, SSL3_AL_FATAL, SSL_AD_DECODE_ERROR);
+ OPENSSL_PUT_ERROR(SSL, SSL_R_DECODE_ERROR);
+ return 0;
+ }
+
+ // Cap the renewable lifetime by the server advertised value. This avoids
+ // wasting bandwidth on 0-RTT when we know the server will reject it.
+ if (session->timeout > server_timeout) {
+ session->timeout = server_timeout;
+ }
+
+ if (!tls13_derive_session_psk(session.get(), ticket_nonce)) {
+ return 0;
+ }
+
+ // Parse out the extensions.
+ bool have_early_data_info = false;
+ CBS early_data_info;
+ const SSL_EXTENSION_TYPE ext_types[] = {
+ {TLSEXT_TYPE_early_data, &have_early_data_info, &early_data_info},
+ };
+
+ uint8_t alert = SSL_AD_DECODE_ERROR;
+ if (!ssl_parse_extensions(&extensions, &alert, ext_types,
+ OPENSSL_ARRAY_SIZE(ext_types),
+ 1 /* ignore unknown */)) {
+ ssl_send_alert(ssl, SSL3_AL_FATAL, alert);
+ return 0;
+ }
+
+ if (have_early_data_info && ssl->cert->enable_early_data) {
+ if (!CBS_get_u32(&early_data_info, &session->ticket_max_early_data) ||
+ CBS_len(&early_data_info) != 0) {
+ ssl_send_alert(ssl, SSL3_AL_FATAL, SSL_AD_DECODE_ERROR);
+ OPENSSL_PUT_ERROR(SSL, SSL_R_DECODE_ERROR);
+ return 0;
+ }
+ }
+
+ session->ticket_age_add_valid = 1;
+ session->not_resumable = 0;
+
+ if ((ssl->ctx->session_cache_mode & SSL_SESS_CACHE_CLIENT) &&
+ ssl->ctx->new_session_cb != NULL &&
+ ssl->ctx->new_session_cb(ssl, session.get())) {
+ // |new_session_cb|'s return value signals that it took ownership.
+ session.release();
+ }
+
+ return 1;
+}
+
+} // namespace bssl