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ssl_tlsext.c
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/* $OpenBSD: ssl_tlsext.c,v 1.154 2024/07/09 12:27:27 beck Exp $ */
/*
* Copyright (c) 2016, 2017, 2019 Joel Sing <jsing@openbsd.org>
* Copyright (c) 2017 Doug Hogan <doug@openbsd.org>
* Copyright (c) 2018-2019, 2024 Bob Beck <beck@openbsd.org>
*
* Permission to use, copy, modify, and 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 <sys/socket.h>
#include <arpa/inet.h>
#include <netinet/in.h>
#include <ctype.h>
#include <openssl/ocsp.h>
#include <openssl/opensslconf.h>
#include "bytestring.h"
#include "ssl_local.h"
#include "ssl_sigalgs.h"
#include "ssl_tlsext.h"
#define TLSEXT_TYPE_alpn TLSEXT_TYPE_application_layer_protocol_negotiation
#define TLSEXT_MAX_SUPPORTED_GROUPS 64
/*
* Supported Application-Layer Protocol Negotiation - RFC 7301
*/
static int
tlsext_alpn_client_needs(SSL *s, uint16_t msg_type)
{
/* ALPN protos have been specified and this is the initial handshake */
return s->alpn_client_proto_list != NULL &&
s->s3->hs.finished_len == 0;
}
static int
tlsext_alpn_client_build(SSL *s, uint16_t msg_type, CBB *cbb)
{
CBB protolist;
if (!CBB_add_u16_length_prefixed(cbb, &protolist))
return 0;
if (!CBB_add_bytes(&protolist, s->alpn_client_proto_list,
s->alpn_client_proto_list_len))
return 0;
if (!CBB_flush(cbb))
return 0;
return 1;
}
int
tlsext_alpn_check_format(CBS *cbs)
{
CBS proto_name_list;
if (CBS_len(cbs) == 0)
return 0;
CBS_dup(cbs, &proto_name_list);
while (CBS_len(&proto_name_list) > 0) {
CBS proto_name;
if (!CBS_get_u8_length_prefixed(&proto_name_list, &proto_name))
return 0;
if (CBS_len(&proto_name) == 0)
return 0;
}
return 1;
}
static int
tlsext_alpn_server_process(SSL *s, uint16_t msg_type, CBS *cbs, int *alert)
{
CBS alpn, selected_cbs;
const unsigned char *selected;
unsigned char selected_len;
int r;
if (!CBS_get_u16_length_prefixed(cbs, &alpn))
return 0;
if (!tlsext_alpn_check_format(&alpn))
return 0;
if (s->ctx->alpn_select_cb == NULL)
return 1;
/*
* XXX - A few things should be considered here:
* 1. Ensure that the same protocol is selected on session resumption.
* 2. Should the callback be called even if no ALPN extension was sent?
* 3. TLSv1.2 and earlier: ensure that SNI has already been processed.
*/
r = s->ctx->alpn_select_cb(s, &selected, &selected_len,
CBS_data(&alpn), CBS_len(&alpn), s->ctx->alpn_select_cb_arg);
if (r == SSL_TLSEXT_ERR_OK) {
CBS_init(&selected_cbs, selected, selected_len);
if (!CBS_stow(&selected_cbs, &s->s3->alpn_selected,
&s->s3->alpn_selected_len)) {
*alert = SSL_AD_INTERNAL_ERROR;
return 0;
}
return 1;
}
/* On SSL_TLSEXT_ERR_NOACK behave as if no callback was present. */
if (r == SSL_TLSEXT_ERR_NOACK)
return 1;
*alert = SSL_AD_NO_APPLICATION_PROTOCOL;
SSLerror(s, SSL_R_NO_APPLICATION_PROTOCOL);
return 0;
}
static int
tlsext_alpn_server_needs(SSL *s, uint16_t msg_type)
{
return s->s3->alpn_selected != NULL;
}
static int
tlsext_alpn_server_build(SSL *s, uint16_t msg_type, CBB *cbb)
{
CBB list, selected;
if (!CBB_add_u16_length_prefixed(cbb, &list))
return 0;
if (!CBB_add_u8_length_prefixed(&list, &selected))
return 0;
if (!CBB_add_bytes(&selected, s->s3->alpn_selected,
s->s3->alpn_selected_len))
return 0;
if (!CBB_flush(cbb))
return 0;
return 1;
}
static int
tlsext_alpn_client_process(SSL *s, uint16_t msg_type, CBS *cbs, int *alert)
{
CBS list, proto;
if (s->alpn_client_proto_list == NULL) {
*alert = SSL_AD_UNSUPPORTED_EXTENSION;
return 0;
}
if (!CBS_get_u16_length_prefixed(cbs, &list))
return 0;
if (!CBS_get_u8_length_prefixed(&list, &proto))
return 0;
if (CBS_len(&list) != 0)
return 0;
if (CBS_len(&proto) == 0)
return 0;
if (!CBS_stow(&proto, &s->s3->alpn_selected, &s->s3->alpn_selected_len))
return 0;
return 1;
}
/*
* Supported Groups - RFC 7919 section 2
*/
static int
tlsext_supportedgroups_client_needs(SSL *s, uint16_t msg_type)
{
return ssl_has_ecc_ciphers(s) ||
(s->s3->hs.our_max_tls_version >= TLS1_3_VERSION);
}
static int
tlsext_supportedgroups_client_build(SSL *s, uint16_t msg_type, CBB *cbb)
{
const uint16_t *groups;
size_t groups_len;
CBB grouplist;
int i;
tls1_get_group_list(s, 0, &groups, &groups_len);
if (groups_len == 0) {
SSLerror(s, ERR_R_INTERNAL_ERROR);
return 0;
}
if (!CBB_add_u16_length_prefixed(cbb, &grouplist))
return 0;
for (i = 0; i < groups_len; i++) {
if (!ssl_security_supported_group(s, groups[i]))
continue;
if (!CBB_add_u16(&grouplist, groups[i]))
return 0;
}
if (!CBB_flush(cbb))
return 0;
return 1;
}
static int
tlsext_supportedgroups_server_process(SSL *s, uint16_t msg_type, CBS *cbs,
int *alert)
{
uint16_t *groups = NULL;
size_t groups_len;
CBS grouplist;
int i, j;
int ret = 0;
if (!CBS_get_u16_length_prefixed(cbs, &grouplist))
goto err;
groups_len = CBS_len(&grouplist);
if (groups_len == 0 || groups_len % 2 != 0)
goto err;
groups_len /= 2;
if (groups_len > TLSEXT_MAX_SUPPORTED_GROUPS)
goto err;
if (s->hit)
goto done;
if (s->s3->hs.tls13.hrr) {
if (s->session->tlsext_supportedgroups == NULL) {
*alert = SSL_AD_HANDSHAKE_FAILURE;
return 0;
}
/*
* The ClientHello extension hashing ensures that the client
* did not change its list of supported groups.
*/
goto done;
}
if (s->session->tlsext_supportedgroups != NULL)
goto err; /* XXX internal error? */
if ((groups = reallocarray(NULL, groups_len, sizeof(uint16_t))) == NULL) {
*alert = SSL_AD_INTERNAL_ERROR;
goto err;
}
for (i = 0; i < groups_len; i++) {
if (!CBS_get_u16(&grouplist, &groups[i]))
goto err;
/*
* Do not allow duplicate groups to be sent. This is not
* currently specified in RFC 8446 or earlier, but there is no
* legitimate justification for this to occur in TLS 1.2 or TLS
* 1.3.
*/
for (j = 0; j < i; j++) {
if (groups[i] == groups[j]) {
*alert = SSL_AD_ILLEGAL_PARAMETER;
goto err;
}
}
}
if (CBS_len(&grouplist) != 0)
goto err;
s->session->tlsext_supportedgroups = groups;
s->session->tlsext_supportedgroups_length = groups_len;
groups = NULL;
done:
ret = 1;
err:
free(groups);
return ret;
}
/* This extension is never used by the server. */
static int
tlsext_supportedgroups_server_needs(SSL *s, uint16_t msg_type)
{
return 0;
}
static int
tlsext_supportedgroups_server_build(SSL *s, uint16_t msg_type, CBB *cbb)
{
return 0;
}
static int
tlsext_supportedgroups_client_process(SSL *s, uint16_t msg_type, CBS *cbs,
int *alert)
{
/*
* This extension is only allowed in TLSv1.3 encrypted extensions.
* It is not permitted in a ServerHello in any version of TLS.
*/
if (msg_type != SSL_TLSEXT_MSG_EE)
return 0;
/*
* RFC 8446, section 4.2.7: TLSv1.3 servers can send this extension but
* clients must not act on it during the handshake. This allows servers
* to advertise their preferences for subsequent handshakes. We ignore
* this complication.
*/
if (!CBS_skip(cbs, CBS_len(cbs))) {
*alert = SSL_AD_INTERNAL_ERROR;
return 0;
}
return 1;
}
/*
* Supported Point Formats Extension - RFC 4492 section 5.1.2
*/
static int
tlsext_ecpf_build(SSL *s, uint16_t msg_type, CBB *cbb)
{
CBB ecpf;
size_t formats_len;
const uint8_t *formats;
tls1_get_formatlist(s, 0, &formats, &formats_len);
if (formats_len == 0) {
SSLerror(s, ERR_R_INTERNAL_ERROR);
return 0;
}
if (!CBB_add_u8_length_prefixed(cbb, &ecpf))
return 0;
if (!CBB_add_bytes(&ecpf, formats, formats_len))
return 0;
if (!CBB_flush(cbb))
return 0;
return 1;
}
static int
tlsext_ecpf_process(SSL *s, uint16_t msg_type, CBS *cbs, int *alert)
{
CBS ecpf;
if (!CBS_get_u8_length_prefixed(cbs, &ecpf))
return 0;
if (CBS_len(&ecpf) == 0)
return 0;
/* Must contain uncompressed (0) - RFC 8422, section 5.1.2. */
if (!CBS_contains_zero_byte(&ecpf)) {
SSLerror(s, SSL_R_TLS_INVALID_ECPOINTFORMAT_LIST);
*alert = SSL_AD_ILLEGAL_PARAMETER;
return 0;
}
if (!s->hit) {
if (!CBS_stow(&ecpf, &(s->session->tlsext_ecpointformatlist),
&(s->session->tlsext_ecpointformatlist_length))) {
*alert = SSL_AD_INTERNAL_ERROR;
return 0;
}
}
return 1;
}
static int
tlsext_ecpf_client_needs(SSL *s, uint16_t msg_type)
{
return ssl_has_ecc_ciphers(s);
}
static int
tlsext_ecpf_client_build(SSL *s, uint16_t msg_type, CBB *cbb)
{
return tlsext_ecpf_build(s, msg_type, cbb);
}
static int
tlsext_ecpf_server_process(SSL *s, uint16_t msg_type, CBS *cbs, int *alert)
{
return tlsext_ecpf_process(s, msg_type, cbs, alert);
}
static int
tlsext_ecpf_server_needs(SSL *s, uint16_t msg_type)
{
return ssl_using_ecc_cipher(s);
}
static int
tlsext_ecpf_server_build(SSL *s, uint16_t msg_type, CBB *cbb)
{
return tlsext_ecpf_build(s, msg_type, cbb);
}
static int
tlsext_ecpf_client_process(SSL *s, uint16_t msg_type, CBS *cbs, int *alert)
{
return tlsext_ecpf_process(s, msg_type, cbs, alert);
}
/*
* Renegotiation Indication - RFC 5746.
*/
static int
tlsext_ri_client_needs(SSL *s, uint16_t msg_type)
{
return (s->renegotiate);
}
static int
tlsext_ri_client_build(SSL *s, uint16_t msg_type, CBB *cbb)
{
CBB reneg;
if (!CBB_add_u8_length_prefixed(cbb, &reneg))
return 0;
if (!CBB_add_bytes(&reneg, s->s3->previous_client_finished,
s->s3->previous_client_finished_len))
return 0;
if (!CBB_flush(cbb))
return 0;
return 1;
}
static int
tlsext_ri_server_process(SSL *s, uint16_t msg_type, CBS *cbs, int *alert)
{
CBS reneg;
if (!CBS_get_u8_length_prefixed(cbs, &reneg)) {
SSLerror(s, SSL_R_RENEGOTIATION_ENCODING_ERR);
return 0;
}
if (!CBS_mem_equal(&reneg, s->s3->previous_client_finished,
s->s3->previous_client_finished_len)) {
SSLerror(s, SSL_R_RENEGOTIATION_MISMATCH);
*alert = SSL_AD_HANDSHAKE_FAILURE;
return 0;
}
s->s3->renegotiate_seen = 1;
s->s3->send_connection_binding = 1;
return 1;
}
static int
tlsext_ri_server_needs(SSL *s, uint16_t msg_type)
{
return (s->s3->hs.negotiated_tls_version < TLS1_3_VERSION &&
s->s3->send_connection_binding);
}
static int
tlsext_ri_server_build(SSL *s, uint16_t msg_type, CBB *cbb)
{
CBB reneg;
if (!CBB_add_u8_length_prefixed(cbb, &reneg))
return 0;
if (!CBB_add_bytes(&reneg, s->s3->previous_client_finished,
s->s3->previous_client_finished_len))
return 0;
if (!CBB_add_bytes(&reneg, s->s3->previous_server_finished,
s->s3->previous_server_finished_len))
return 0;
if (!CBB_flush(cbb))
return 0;
return 1;
}
static int
tlsext_ri_client_process(SSL *s, uint16_t msg_type, CBS *cbs, int *alert)
{
CBS reneg, prev_client, prev_server;
/*
* Ensure that the previous client and server values are both not
* present, or that they are both present.
*/
if ((s->s3->previous_client_finished_len == 0 &&
s->s3->previous_server_finished_len != 0) ||
(s->s3->previous_client_finished_len != 0 &&
s->s3->previous_server_finished_len == 0)) {
*alert = SSL_AD_INTERNAL_ERROR;
return 0;
}
if (!CBS_get_u8_length_prefixed(cbs, &reneg)) {
SSLerror(s, SSL_R_RENEGOTIATION_ENCODING_ERR);
return 0;
}
if (!CBS_get_bytes(&reneg, &prev_client,
s->s3->previous_client_finished_len)) {
SSLerror(s, SSL_R_RENEGOTIATION_ENCODING_ERR);
return 0;
}
if (!CBS_get_bytes(&reneg, &prev_server,
s->s3->previous_server_finished_len)) {
SSLerror(s, SSL_R_RENEGOTIATION_ENCODING_ERR);
return 0;
}
if (CBS_len(&reneg) != 0) {
SSLerror(s, SSL_R_RENEGOTIATION_ENCODING_ERR);
return 0;
}
if (!CBS_mem_equal(&prev_client, s->s3->previous_client_finished,
s->s3->previous_client_finished_len)) {
SSLerror(s, SSL_R_RENEGOTIATION_MISMATCH);
*alert = SSL_AD_HANDSHAKE_FAILURE;
return 0;
}
if (!CBS_mem_equal(&prev_server, s->s3->previous_server_finished,
s->s3->previous_server_finished_len)) {
SSLerror(s, SSL_R_RENEGOTIATION_MISMATCH);
*alert = SSL_AD_HANDSHAKE_FAILURE;
return 0;
}
s->s3->renegotiate_seen = 1;
s->s3->send_connection_binding = 1;
return 1;
}
/*
* Signature Algorithms - RFC 5246 section 7.4.1.4.1.
*/
static int
tlsext_sigalgs_client_needs(SSL *s, uint16_t msg_type)
{
return (s->s3->hs.our_max_tls_version >= TLS1_2_VERSION);
}
static int
tlsext_sigalgs_client_build(SSL *s, uint16_t msg_type, CBB *cbb)
{
uint16_t tls_version = s->s3->hs.negotiated_tls_version;
CBB sigalgs;
if (msg_type == SSL_TLSEXT_MSG_CH)
tls_version = s->s3->hs.our_min_tls_version;
if (!CBB_add_u16_length_prefixed(cbb, &sigalgs))
return 0;
if (!ssl_sigalgs_build(tls_version, &sigalgs, SSL_get_security_level(s)))
return 0;
if (!CBB_flush(cbb))
return 0;
return 1;
}
static int
tlsext_sigalgs_server_process(SSL *s, uint16_t msg_type, CBS *cbs, int *alert)
{
CBS sigalgs;
if (!CBS_get_u16_length_prefixed(cbs, &sigalgs))
return 0;
if (CBS_len(&sigalgs) % 2 != 0 || CBS_len(&sigalgs) > 64)
return 0;
if (!CBS_stow(&sigalgs, &s->s3->hs.sigalgs, &s->s3->hs.sigalgs_len))
return 0;
return 1;
}
static int
tlsext_sigalgs_server_needs(SSL *s, uint16_t msg_type)
{
return (s->s3->hs.negotiated_tls_version >= TLS1_3_VERSION);
}
static int
tlsext_sigalgs_server_build(SSL *s, uint16_t msg_type, CBB *cbb)
{
CBB sigalgs;
if (!CBB_add_u16_length_prefixed(cbb, &sigalgs))
return 0;
if (!ssl_sigalgs_build(s->s3->hs.negotiated_tls_version, &sigalgs,
SSL_get_security_level(s)))
return 0;
if (!CBB_flush(cbb))
return 0;
return 1;
}
static int
tlsext_sigalgs_client_process(SSL *s, uint16_t msg_type, CBS *cbs, int *alert)
{
CBS sigalgs;
if (ssl_effective_tls_version(s) < TLS1_3_VERSION)
return 0;
if (!CBS_get_u16_length_prefixed(cbs, &sigalgs))
return 0;
if (CBS_len(&sigalgs) % 2 != 0 || CBS_len(&sigalgs) > 64)
return 0;
if (!CBS_stow(&sigalgs, &s->s3->hs.sigalgs, &s->s3->hs.sigalgs_len))
return 0;
return 1;
}
/*
* Server Name Indication - RFC 6066, section 3.
*/
static int
tlsext_sni_client_needs(SSL *s, uint16_t msg_type)
{
return (s->tlsext_hostname != NULL);
}
static int
tlsext_sni_client_build(SSL *s, uint16_t msg_type, CBB *cbb)
{
CBB server_name_list, host_name;
if (!CBB_add_u16_length_prefixed(cbb, &server_name_list))
return 0;
if (!CBB_add_u8(&server_name_list, TLSEXT_NAMETYPE_host_name))
return 0;
if (!CBB_add_u16_length_prefixed(&server_name_list, &host_name))
return 0;
if (!CBB_add_bytes(&host_name, (const uint8_t *)s->tlsext_hostname,
strlen(s->tlsext_hostname)))
return 0;
if (!CBB_flush(cbb))
return 0;
return 1;
}
static int
tlsext_sni_is_ip_literal(CBS *cbs, int *is_ip)
{
union {
struct in_addr ip4;
struct in6_addr ip6;
} addrbuf;
char *hostname = NULL;
*is_ip = 0;
if (!CBS_strdup(cbs, &hostname))
return 0;
if (inet_pton(AF_INET, hostname, &addrbuf) == 1 ||
inet_pton(AF_INET6, hostname, &addrbuf) == 1)
*is_ip = 1;
free(hostname);
return 1;
}
/*
* Validate that the CBS contains only a hostname consisting of RFC 5890
* compliant A-labels (see RFC 6066 section 3). Not a complete check
* since we don't parse punycode to verify its validity but limits to
* correct structure and character set.
*/
int
tlsext_sni_is_valid_hostname(CBS *cbs, int *is_ip)
{
uint8_t prev, c = 0;
int component = 0;
CBS hostname;
*is_ip = 0;
CBS_dup(cbs, &hostname);
if (CBS_len(&hostname) > TLSEXT_MAXLEN_host_name)
return 0;
/* An IP literal is invalid as a host name (RFC 6066 section 3). */
if (!tlsext_sni_is_ip_literal(&hostname, is_ip))
return 0;
if (*is_ip)
return 0;
while (CBS_len(&hostname) > 0) {
prev = c;
if (!CBS_get_u8(&hostname, &c))
return 0;
/* Everything has to be ASCII, with no NUL byte. */
if (!isascii(c) || c == '\0')
return 0;
/* It must be alphanumeric, a '-', or a '.' */
if (!isalnum(c) && c != '-' && c != '.')
return 0;
/* '-' and '.' must not start a component or be at the end. */
if (component == 0 || CBS_len(&hostname) == 0) {
if (c == '-' || c == '.')
return 0;
}
if (c == '.') {
/* Components can not end with a dash. */
if (prev == '-')
return 0;
/* Start new component */
component = 0;
continue;
}
/* Components must be 63 chars or less. */
if (++component > 63)
return 0;
}
return 1;
}
static int
tlsext_sni_server_process(SSL *s, uint16_t msg_type, CBS *cbs, int *alert)
{
CBS server_name_list, host_name;
uint8_t name_type;
int is_ip;
if (!CBS_get_u16_length_prefixed(cbs, &server_name_list))
goto err;
if (!CBS_get_u8(&server_name_list, &name_type))
goto err;
/*
* RFC 6066 section 3, only one type (host_name) is specified.
* We do not tolerate unknown types, neither does BoringSSL.
* other implementations appear more tolerant.
*/
if (name_type != TLSEXT_NAMETYPE_host_name) {
*alert = SSL_AD_ILLEGAL_PARAMETER;
goto err;
}
/*
* RFC 6066 section 3 specifies a host name must be at least 1 byte
* so 0 length is a decode error.
*/
if (!CBS_get_u16_length_prefixed(&server_name_list, &host_name))
goto err;
if (CBS_len(&host_name) < 1)
goto err;
if (!tlsext_sni_is_valid_hostname(&host_name, &is_ip)) {
/*
* Various pieces of software have been known to set the SNI
* host name to an IP address, even though that violates the
* RFC. If this is the case, pretend the SNI extension does
* not exist.
*/
if (is_ip)
goto done;
*alert = SSL_AD_ILLEGAL_PARAMETER;
goto err;
}
if (s->hit || s->s3->hs.tls13.hrr) {
if (s->session->tlsext_hostname == NULL) {
*alert = SSL_AD_UNRECOGNIZED_NAME;
goto err;
}
if (!CBS_mem_equal(&host_name, s->session->tlsext_hostname,
strlen(s->session->tlsext_hostname))) {
*alert = SSL_AD_UNRECOGNIZED_NAME;
goto err;
}
} else {
if (s->session->tlsext_hostname != NULL)
goto err;
if (!CBS_strdup(&host_name, &s->session->tlsext_hostname)) {
*alert = SSL_AD_INTERNAL_ERROR;
goto err;
}
}
done:
/*
* RFC 6066 section 3 forbids multiple host names with the same type,
* therefore we allow only one entry.
*/
if (CBS_len(&server_name_list) != 0) {
*alert = SSL_AD_ILLEGAL_PARAMETER;
goto err;
}
return 1;
err:
return 0;
}
static int
tlsext_sni_server_needs(SSL *s, uint16_t msg_type)
{
if (s->hit)
return 0;
return (s->session->tlsext_hostname != NULL);
}
static int
tlsext_sni_server_build(SSL *s, uint16_t msg_type, CBB *cbb)
{
return 1;
}
static int
tlsext_sni_client_process(SSL *s, uint16_t msg_type, CBS *cbs, int *alert)
{
if (s->tlsext_hostname == NULL || CBS_len(cbs) != 0) {
*alert = SSL_AD_UNRECOGNIZED_NAME;
return 0;
}
if (s->hit) {
if (s->session->tlsext_hostname == NULL) {
*alert = SSL_AD_UNRECOGNIZED_NAME;
return 0;
}
if (strcmp(s->tlsext_hostname,
s->session->tlsext_hostname) != 0) {
*alert = SSL_AD_UNRECOGNIZED_NAME;
return 0;
}
} else {
if (s->session->tlsext_hostname != NULL)
return 0;
if ((s->session->tlsext_hostname =
strdup(s->tlsext_hostname)) == NULL) {
*alert = SSL_AD_INTERNAL_ERROR;
return 0;
}
}
return 1;
}
/*
* Certificate Status Request - RFC 6066 section 8.
*/
static int
tlsext_ocsp_client_needs(SSL *s, uint16_t msg_type)
{
if (msg_type != SSL_TLSEXT_MSG_CH)
return 0;
return (s->tlsext_status_type == TLSEXT_STATUSTYPE_ocsp);
}
static int
tlsext_ocsp_client_build(SSL *s, uint16_t msg_type, CBB *cbb)
{
CBB respid_list, respid, exts;
unsigned char *ext_data;
size_t ext_len;
int i;
if (!CBB_add_u8(cbb, TLSEXT_STATUSTYPE_ocsp))
return 0;
if (!CBB_add_u16_length_prefixed(cbb, &respid_list))
return 0;
for (i = 0; i < sk_OCSP_RESPID_num(s->tlsext_ocsp_ids); i++) {
unsigned char *respid_data;
OCSP_RESPID *id;
size_t id_len;
if ((id = sk_OCSP_RESPID_value(s->tlsext_ocsp_ids,
i)) == NULL)
return 0;
if ((id_len = i2d_OCSP_RESPID(id, NULL)) == -1)
return 0;
if (!CBB_add_u16_length_prefixed(&respid_list, &respid))
return 0;
if (!CBB_add_space(&respid, &respid_data, id_len))
return 0;
if ((i2d_OCSP_RESPID(id, &respid_data)) != id_len)
return 0;
}
if (!CBB_add_u16_length_prefixed(cbb, &exts))
return 0;
if ((ext_len = i2d_X509_EXTENSIONS(s->tlsext_ocsp_exts,
NULL)) == -1)
return 0;
if (!CBB_add_space(&exts, &ext_data, ext_len))
return 0;
if ((i2d_X509_EXTENSIONS(s->tlsext_ocsp_exts, &ext_data) !=
ext_len))
return 0;
if (!CBB_flush(cbb))
return 0;
return 1;
}
static int
tlsext_ocsp_server_process(SSL *s, uint16_t msg_type, CBS *cbs, int *alert)
{
int alert_desc = SSL_AD_DECODE_ERROR;
CBS respid_list, respid, exts;
const unsigned char *p;
uint8_t status_type;
int ret = 0;
if (msg_type != SSL_TLSEXT_MSG_CH)
goto err;
if (!CBS_get_u8(cbs, &status_type))
goto err;
if (status_type != TLSEXT_STATUSTYPE_ocsp) {
/* ignore unknown status types */
s->tlsext_status_type = -1;
if (!CBS_skip(cbs, CBS_len(cbs))) {
*alert = SSL_AD_INTERNAL_ERROR;
return 0;
}
return 1;
}
s->tlsext_status_type = status_type;
if (!CBS_get_u16_length_prefixed(cbs, &respid_list))
goto err;
/* XXX */
sk_OCSP_RESPID_pop_free(s->tlsext_ocsp_ids, OCSP_RESPID_free);
s->tlsext_ocsp_ids = NULL;
if (CBS_len(&respid_list) > 0) {
s->tlsext_ocsp_ids = sk_OCSP_RESPID_new_null();
if (s->tlsext_ocsp_ids == NULL) {
alert_desc = SSL_AD_INTERNAL_ERROR;
goto err;
}
}
while (CBS_len(&respid_list) > 0) {
OCSP_RESPID *id;
if (!CBS_get_u16_length_prefixed(&respid_list, &respid))
goto err;
p = CBS_data(&respid);
if ((id = d2i_OCSP_RESPID(NULL, &p, CBS_len(&respid))) == NULL)
goto err;
if (!sk_OCSP_RESPID_push(s->tlsext_ocsp_ids, id)) {
alert_desc = SSL_AD_INTERNAL_ERROR;
OCSP_RESPID_free(id);
goto err;
}
}
/* Read in request_extensions */
if (!CBS_get_u16_length_prefixed(cbs, &exts))
goto err;