kris/boringssl
1
0
Fork 0
Code Issues Pull Requests Releases Wiki Activity
1dc53d2840
boringssl/ssl/tls13_client.c
Steven Valdez 87eab4902d Splitting SSL session state. 
To prevent configuration/established session confusion, the handshake
session state is separated into the configured session (ssl->session)
and the newly created session (ssl->s3->new_session). Upon conclusion of
the handshake, the finalized session is stored
in (ssl->s3->established_session). During the handshake, any requests
for the session (SSL_get_session) return a non-resumable session, to
prevent resumption of a partially filled session. Sessions should only
be cached upon the completion of the full handshake, using the resulting
established_session. The semantics of accessors on the session are
maintained mid-renego.

Change-Id: I4358aecb71fce4fe14a6746c5af1416a69935078
Reviewed-on: https://boringssl-review.googlesource.com/8612
Reviewed-by: David Benjamin <davidben@google.com>
Commit-Queue: David Benjamin <davidben@google.com>
CQ-Verified: CQ bot account: commit-bot@chromium.org <commit-bot@chromium.org>
2016-07-29 21:22:46 +00:00

559 lines
18 KiB
C
Raw Blame History

/* 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 <openssl/bytestring.h>
#include <openssl/digest.h>
#include <openssl/err.h>
#include <openssl/mem.h>
#include <openssl/stack.h>
#include <openssl/x509.h>
#include "internal.h"
enum client_hs_state_t {
state_process_hello_retry_request = 0,
state_send_second_client_hello,
state_flush_second_client_hello,
state_process_server_hello,
state_process_encrypted_extensions,
state_process_certificate_request,
state_process_server_certificate,
state_process_server_certificate_verify,
state_process_server_finished,
state_certificate_callback,
state_send_client_certificate,
state_send_client_certificate_verify,
state_complete_client_certificate_verify,
state_send_client_finished,
state_flush,
state_done,
};
static enum ssl_hs_wait_t do_process_hello_retry_request(SSL *ssl,
SSL_HANDSHAKE *hs) {
if (ssl->s3->tmp.message_type != SSL3_MT_HELLO_RETRY_REQUEST) {
hs->state = state_process_server_hello;
return ssl_hs_ok;
}
CBS cbs, extensions;
uint16_t server_wire_version, cipher_suite, group_id;
CBS_init(&cbs, ssl->init_msg, ssl->init_num);
if (!CBS_get_u16(&cbs, &server_wire_version) ||
!CBS_get_u16(&cbs, &cipher_suite) ||
!CBS_get_u16(&cbs, &group_id) ||
/* We do not currently parse any HelloRetryRequest extensions. */
!CBS_get_u16_length_prefixed(&cbs, &extensions) ||
CBS_len(&cbs) != 0) {
ssl3_send_alert(ssl, SSL3_AL_FATAL, SSL_AD_DECODE_ERROR);
return ssl_hs_error;
}
/* TODO(svaldez): Don't do early_data on HelloRetryRequest. */
const uint16_t *groups;
size_t groups_len;
tls1_get_grouplist(ssl, 0 /* local groups */, &groups, &groups_len);
int found = 0;
for (size_t i = 0; i < groups_len; i++) {
if (groups[i] == group_id) {
found = 1;
break;
}
}
if (!found) {
ssl3_send_alert(ssl, SSL3_AL_FATAL, SSL_AD_ILLEGAL_PARAMETER);
OPENSSL_PUT_ERROR(SSL, SSL_R_WRONG_CURVE);
return ssl_hs_error;
}
for (size_t i = 0; i < ssl->s3->hs->groups_len; i++) {
/* Check that the HelloRetryRequest does not request a key share that was
* provided in the initial ClientHello.
*
* TODO(svaldez): Don't enforce this check when the HelloRetryRequest is due
* to a cookie. */
if (SSL_ECDH_CTX_get_id(&ssl->s3->hs->groups[i]) == group_id) {
ssl3_send_alert(ssl, SSL3_AL_FATAL, SSL_AD_ILLEGAL_PARAMETER);
OPENSSL_PUT_ERROR(SSL, SSL_R_WRONG_CURVE);
return ssl_hs_error;
}
}
ssl_handshake_clear_groups(ssl->s3->hs);
ssl->s3->hs->retry_group = group_id;
hs->state = state_send_second_client_hello;
return ssl_hs_ok;
}
static enum ssl_hs_wait_t do_send_second_client_hello(SSL *ssl,
SSL_HANDSHAKE *hs) {
CBB cbb, body;
if (!ssl->method->init_message(ssl, &cbb, &body, SSL3_MT_CLIENT_HELLO) ||
!ssl_add_client_hello_body(ssl, &body) ||
!ssl->method->finish_message(ssl, &cbb)) {
CBB_cleanup(&cbb);
return ssl_hs_error;
}
hs->state = state_flush_second_client_hello;
return ssl_hs_write_message;
}
static enum ssl_hs_wait_t do_flush_second_client_hello(SSL *ssl,
SSL_HANDSHAKE *hs) {
hs->state = state_process_server_hello;
return ssl_hs_flush_and_read_message;
}
static enum ssl_hs_wait_t do_process_server_hello(SSL *ssl, SSL_HANDSHAKE *hs) {
if (!tls13_check_message_type(ssl, SSL3_MT_SERVER_HELLO)) {
return ssl_hs_error;
}
CBS cbs, server_random, extensions;
uint16_t server_wire_version;
uint16_t cipher_suite;
CBS_init(&cbs, ssl->init_msg, ssl->init_num);
if (!CBS_get_u16(&cbs, &server_wire_version) ||
!CBS_get_bytes(&cbs, &server_random, SSL3_RANDOM_SIZE) ||
!CBS_get_u16(&cbs, &cipher_suite) ||
!CBS_get_u16_length_prefixed(&cbs, &extensions) ||
CBS_len(&cbs) != 0) {
ssl3_send_alert(ssl, SSL3_AL_FATAL, SSL_AD_DECODE_ERROR);
OPENSSL_PUT_ERROR(SSL, SSL_R_DECODE_ERROR);
return ssl_hs_error;
}
if (server_wire_version != ssl->version) {
ssl3_send_alert(ssl, SSL3_AL_FATAL, SSL_AD_DECODE_ERROR);
OPENSSL_PUT_ERROR(SSL, SSL_R_WRONG_VERSION_NUMBER);
return ssl_hs_error;
}
/* Parse out the extensions. */
int have_key_share = 0;
CBS key_share;
while (CBS_len(&extensions) != 0) {
uint16_t type;
CBS extension;
if (!CBS_get_u16(&extensions, &type) ||
!CBS_get_u16_length_prefixed(&extensions, &extension)) {
OPENSSL_PUT_ERROR(SSL, SSL_R_PARSE_TLSEXT);
ssl3_send_alert(ssl, SSL3_AL_FATAL, SSL_AD_DECODE_ERROR);
return ssl_hs_error;
}
switch (type) {
case TLSEXT_TYPE_key_share:
if (have_key_share) {
OPENSSL_PUT_ERROR(SSL, SSL_R_DUPLICATE_EXTENSION);
ssl3_send_alert(ssl, SSL3_AL_FATAL, SSL_AD_DECODE_ERROR);
return ssl_hs_error;
}
key_share = extension;
have_key_share = 1;
break;
default:
OPENSSL_PUT_ERROR(SSL, SSL_R_UNEXPECTED_EXTENSION);
ssl3_send_alert(ssl, SSL3_AL_FATAL, SSL_AD_UNSUPPORTED_EXTENSION);
return ssl_hs_error;
}
}
assert(ssl->s3->have_version);
memcpy(ssl->s3->server_random, CBS_data(&server_random), SSL3_RANDOM_SIZE);
SSL_set_session(ssl, NULL);
if (!ssl_get_new_session(ssl, 0)) {
ssl3_send_alert(ssl, SSL3_AL_FATAL, SSL_AD_INTERNAL_ERROR);
return ssl_hs_error;
}
const SSL_CIPHER *cipher = SSL_get_cipher_by_value(cipher_suite);
if (cipher == NULL) {
OPENSSL_PUT_ERROR(SSL, SSL_R_UNKNOWN_CIPHER_RETURNED);
ssl3_send_alert(ssl, SSL3_AL_FATAL, SSL_AD_ILLEGAL_PARAMETER);
return ssl_hs_error;
}
/* Check if the cipher is disabled. */
if ((cipher->algorithm_mkey & ssl->cert->mask_k) ||
(cipher->algorithm_auth & ssl->cert->mask_a) ||
SSL_CIPHER_get_min_version(cipher) > ssl3_protocol_version(ssl) ||
SSL_CIPHER_get_max_version(cipher) < ssl3_protocol_version(ssl) ||
!sk_SSL_CIPHER_find(ssl_get_ciphers_by_id(ssl), NULL, cipher)) {
OPENSSL_PUT_ERROR(SSL, SSL_R_WRONG_CIPHER_RETURNED);
ssl3_send_alert(ssl, SSL3_AL_FATAL, SSL_AD_ILLEGAL_PARAMETER);
return ssl_hs_error;
}
ssl->s3->new_session->cipher = cipher;
ssl->s3->tmp.new_cipher = cipher;
/* The PRF hash is now known. Set up the key schedule. */
static const uint8_t kZeroes[EVP_MAX_MD_SIZE] = {0};
size_t hash_len =
EVP_MD_size(ssl_get_handshake_digest(ssl_get_algorithm_prf(ssl)));
if (!tls13_init_key_schedule(ssl, kZeroes, hash_len)) {
return ssl_hs_error;
}
/* Resolve PSK and incorporate it into the secret. */
if (cipher->algorithm_auth == SSL_aPSK) {
/* TODO(davidben): Support PSK. */
OPENSSL_PUT_ERROR(SSL, ERR_R_INTERNAL_ERROR);
return ssl_hs_error;
} else if (!tls13_advance_key_schedule(ssl, kZeroes, hash_len)) {
return ssl_hs_error;
}
/* Resolve ECDHE and incorporate it into the secret. */
if (cipher->algorithm_mkey == SSL_kECDHE) {
if (!have_key_share) {
OPENSSL_PUT_ERROR(SSL, SSL_R_MISSING_KEY_SHARE);
ssl3_send_alert(ssl, SSL3_AL_FATAL, SSL_AD_MISSING_EXTENSION);
return ssl_hs_error;
}
uint8_t *dhe_secret;
size_t dhe_secret_len;
uint8_t alert = SSL_AD_DECODE_ERROR;
if (!ext_key_share_parse_serverhello(ssl, &dhe_secret, &dhe_secret_len,
&alert, &key_share)) {
ssl3_send_alert(ssl, SSL3_AL_FATAL, alert);
return ssl_hs_error;
}
int ok = tls13_advance_key_schedule(ssl, dhe_secret, dhe_secret_len);
OPENSSL_free(dhe_secret);
if (!ok) {
return ssl_hs_error;
}
} else {
if (have_key_share) {
OPENSSL_PUT_ERROR(SSL, SSL_R_UNEXPECTED_EXTENSION);
ssl3_send_alert(ssl, SSL3_AL_FATAL, SSL_AD_UNSUPPORTED_EXTENSION);
return ssl_hs_error;
}
if (!tls13_advance_key_schedule(ssl, kZeroes, hash_len)) {
return ssl_hs_error;
}
}
/* If there was no HelloRetryRequest, the version negotiation logic has
* already hashed the message. */
if (ssl->s3->hs->retry_group != 0 &&
!ssl->method->hash_current_message(ssl)) {
return ssl_hs_error;
}
if (!tls13_set_handshake_traffic(ssl)) {
return ssl_hs_error;
}
hs->state = state_process_encrypted_extensions;
return ssl_hs_read_message;
}
static enum ssl_hs_wait_t do_process_encrypted_extensions(SSL *ssl,
SSL_HANDSHAKE *hs) {
if (!tls13_check_message_type(ssl, SSL3_MT_ENCRYPTED_EXTENSIONS)) {
return ssl_hs_error;
}
CBS cbs;
CBS_init(&cbs, ssl->init_msg, ssl->init_num);
if (!ssl_parse_serverhello_tlsext(ssl, &cbs)) {
OPENSSL_PUT_ERROR(SSL, SSL_R_PARSE_TLSEXT);
return ssl_hs_error;
}
if (CBS_len(&cbs) != 0) {
OPENSSL_PUT_ERROR(SSL, SSL_R_DECODE_ERROR);
ssl3_send_alert(ssl, SSL3_AL_FATAL, SSL_AD_DECODE_ERROR);
return ssl_hs_error;
}
if (!ssl->method->hash_current_message(ssl)) {
return ssl_hs_error;
}
hs->state = state_process_certificate_request;
return ssl_hs_read_message;
}
static enum ssl_hs_wait_t do_process_certificate_request(SSL *ssl,
SSL_HANDSHAKE *hs) {
ssl->s3->tmp.cert_request = 0;
/* CertificateRequest may only be sent in certificate-based ciphers. */
if (!ssl_cipher_uses_certificate_auth(ssl->s3->tmp.new_cipher)) {
hs->state = state_process_server_finished;
return ssl_hs_ok;
}
/* CertificateRequest is optional. */
if (ssl->s3->tmp.message_type != SSL3_MT_CERTIFICATE_REQUEST) {
hs->state = state_process_server_certificate;
return ssl_hs_ok;
}
CBS cbs, context, supported_signature_algorithms;
CBS_init(&cbs, ssl->init_msg, ssl->init_num);
if (!CBS_get_u8_length_prefixed(&cbs, &context) ||
!CBS_stow(&context, &ssl->s3->hs->cert_context,
&ssl->s3->hs->cert_context_len) ||
!CBS_get_u16_length_prefixed(&cbs, &supported_signature_algorithms) ||
!tls1_parse_peer_sigalgs(ssl, &supported_signature_algorithms)) {
ssl3_send_alert(ssl, SSL3_AL_FATAL, SSL_AD_DECODE_ERROR);
OPENSSL_PUT_ERROR(SSL, SSL_R_DECODE_ERROR);
return ssl_hs_error;
}
uint8_t alert;
STACK_OF(X509_NAME) *ca_sk = ssl_parse_client_CA_list(ssl, &alert, &cbs);
if (ca_sk == NULL) {
ssl3_send_alert(ssl, SSL3_AL_FATAL, alert);
return ssl_hs_error;
}
/* Ignore extensions. */
CBS extensions;
if (!CBS_get_u16_length_prefixed(&cbs, &extensions) ||
CBS_len(&cbs) != 0) {
ssl3_send_alert(ssl, SSL3_AL_FATAL, SSL_AD_DECODE_ERROR);
OPENSSL_PUT_ERROR(SSL, SSL_R_DECODE_ERROR);
return ssl_hs_error;
}
ssl->s3->tmp.cert_request = 1;
sk_X509_NAME_pop_free(ssl->s3->tmp.ca_names, X509_NAME_free);
ssl->s3->tmp.ca_names = ca_sk;
if (!ssl->method->hash_current_message(ssl)) {
return ssl_hs_error;
}
hs->state = state_process_server_certificate;
return ssl_hs_read_message;
}
static enum ssl_hs_wait_t do_process_server_certificate(SSL *ssl,
SSL_HANDSHAKE *hs) {
if (!tls13_check_message_type(ssl, SSL3_MT_CERTIFICATE) ||
!tls13_process_certificate(ssl) ||
!ssl->method->hash_current_message(ssl)) {
return ssl_hs_error;
}
hs->state = state_process_server_certificate_verify;
return ssl_hs_read_message;
}
static enum ssl_hs_wait_t do_process_server_certificate_verify(
SSL *ssl, SSL_HANDSHAKE *hs) {
if (!tls13_check_message_type(ssl, SSL3_MT_CERTIFICATE_VERIFY) ||
!tls13_process_certificate_verify(ssl) ||
!ssl->method->hash_current_message(ssl)) {
return 0;
}
hs->state = state_process_server_finished;
return ssl_hs_read_message;
}
static enum ssl_hs_wait_t do_process_server_finished(SSL *ssl,
SSL_HANDSHAKE *hs) {
static const uint8_t kZeroes[EVP_MAX_MD_SIZE] = {0};
if (!tls13_check_message_type(ssl, SSL3_MT_FINISHED) ||
!tls13_process_finished(ssl) ||
!ssl->method->hash_current_message(ssl) ||
/* Update the secret to the master secret and derive traffic keys. */
!tls13_advance_key_schedule(ssl, kZeroes, hs->hash_len) ||
!tls13_derive_traffic_secret_0(ssl)) {
return ssl_hs_error;
}
ssl->method->received_flight(ssl);
hs->state = state_certificate_callback;
return ssl_hs_ok;
}
static enum ssl_hs_wait_t do_certificate_callback(SSL *ssl, SSL_HANDSHAKE *hs) {
/* The peer didn't request a certificate. */
if (!ssl->s3->tmp.cert_request) {
hs->state = state_send_client_finished;
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) {
ssl3_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->state = state_certificate_callback;
return ssl_hs_x509_lookup;
}
}
hs->state = state_send_client_certificate;
return ssl_hs_ok;
}
static enum ssl_hs_wait_t do_send_client_certificate(SSL *ssl,
SSL_HANDSHAKE *hs) {
/* Call client_cert_cb to update the certificate. */
int should_retry;
if (!ssl_do_client_cert_cb(ssl, &should_retry)) {
if (should_retry) {
hs->state = state_send_client_certificate;
return ssl_hs_x509_lookup;
}
return ssl_hs_error;
}
if (!tls13_prepare_certificate(ssl)) {
return ssl_hs_error;
}
hs->state = state_send_client_certificate_verify;
return ssl_hs_write_message;
}
static enum ssl_hs_wait_t do_send_client_certificate_verify(SSL *ssl,
SSL_HANDSHAKE *hs,
int is_first_run) {
/* Don't send CertificateVerify if there is no certificate. */
if (!ssl_has_certificate(ssl)) {
hs->state = state_send_client_finished;
return ssl_hs_ok;
}
switch (tls13_prepare_certificate_verify(ssl, is_first_run)) {
case ssl_private_key_success:
hs->state = state_send_client_finished;
return ssl_hs_write_message;
case ssl_private_key_retry:
hs->state = state_complete_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_send_client_finished(SSL *ssl, SSL_HANDSHAKE *hs) {
if (!tls13_prepare_finished(ssl)) {
return ssl_hs_error;
}
hs->state = state_flush;
return ssl_hs_write_message;
}
static enum ssl_hs_wait_t do_flush(SSL *ssl, SSL_HANDSHAKE *hs) {
if (!tls13_set_traffic_key(ssl, type_data, evp_aead_open,
hs->traffic_secret_0, hs->hash_len) ||
!tls13_set_traffic_key(ssl, type_data, evp_aead_seal,
hs->traffic_secret_0, hs->hash_len) ||
!tls13_finalize_keys(ssl)) {
return ssl_hs_error;
}
hs->state = state_done;
return ssl_hs_flush;
}
enum ssl_hs_wait_t tls13_client_handshake(SSL *ssl) {
SSL_HANDSHAKE *hs = ssl->s3->hs;
while (hs->state != state_done) {
enum ssl_hs_wait_t ret = ssl_hs_error;
enum client_hs_state_t state = hs->state;
switch (state) {
case state_process_hello_retry_request:
ret = do_process_hello_retry_request(ssl, hs);
break;
case state_send_second_client_hello:
ret = do_send_second_client_hello(ssl, hs);
break;
case state_flush_second_client_hello:
ret = do_flush_second_client_hello(ssl, hs);
break;
case state_process_server_hello:
ret = do_process_server_hello(ssl, hs);
break;
case state_process_encrypted_extensions:
ret = do_process_encrypted_extensions(ssl, hs);
break;
case state_process_certificate_request:
ret = do_process_certificate_request(ssl, hs);
break;
case state_process_server_certificate:
ret = do_process_server_certificate(ssl, hs);
break;
case state_process_server_certificate_verify:
ret = do_process_server_certificate_verify(ssl, hs);
break;
case state_process_server_finished:
ret = do_process_server_finished(ssl, hs);
break;
case state_certificate_callback:
ret = do_certificate_callback(ssl, hs);
break;
case state_send_client_certificate:
ret = do_send_client_certificate(ssl, hs);
break;
case state_send_client_certificate_verify:
ret = do_send_client_certificate_verify(ssl, hs, 1 /* first run */);
break;
case state_complete_client_certificate_verify:
ret = do_send_client_certificate_verify(ssl, hs, 0 /* complete */);
break;
case state_send_client_finished:
ret = do_send_client_finished(ssl, hs);
break;
case state_flush:
ret = do_flush(ssl, hs);
break;
case state_done:
ret = ssl_hs_ok;
break;
}
if (ret != ssl_hs_ok) {
return ret;
}
}
return ssl_hs_ok;
}
Reference in New Issue View Git Blame Copy Permalink