/* ssl/t1_lib.c */
/* Copyright (C) 1995-1998 Eric Young (eay@cryptsoft.com)
* All rights reserved.
*
* This package is an SSL implementation written
* by Eric Young (eay@cryptsoft.com).
* The implementation was written so as to conform with Netscapes SSL.
*
* This library is free for commercial and non-commercial use as long as
* the following conditions are aheared to. The following conditions
* apply to all code found in this distribution, be it the RC4, RSA,
* lhash, DES, etc., code; not just the SSL code. The SSL documentation
* included with this distribution is covered by the same copyright terms
* except that the holder is Tim Hudson (tjh@cryptsoft.com).
*
* Copyright remains Eric Young's, and as such any Copyright notices in
* the code are not to be removed.
* If this package is used in a product, Eric Young should be given attribution
* as the author of the parts of the library used.
* This can be in the form of a textual message at program startup or
* in documentation (online or textual) provided with the package.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
* 1. Redistributions of source code must retain the copyright
* notice, this list of conditions and the following disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
* 3. All advertising materials mentioning features or use of this software
* must display the following acknowledgement:
* "This product includes cryptographic software written by
* Eric Young (eay@cryptsoft.com)"
* The word 'cryptographic' can be left out if the rouines from the library
* being used are not cryptographic related :-).
* 4. If you include any Windows specific code (or a derivative thereof) from
* the apps directory (application code) you must include an acknowledgement:
* "This product includes software written by Tim Hudson (tjh@cryptsoft.com)"
*
* THIS SOFTWARE IS PROVIDED BY ERIC YOUNG ``AS IS'' AND
* ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
* ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
* FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
* DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
* OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
* HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
* LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
* OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
* SUCH DAMAGE.
*
* The licence and distribution terms for any publically available version or
* derivative of this code cannot be changed. i.e. this code cannot simply be
* copied and put under another distribution licence
* [including the GNU Public Licence.]
*/
#include <stdio.h>
#include <openssl/objects.h>
#include <openssl/evp.h>
#include <openssl/hmac.h>
#include "ssl_locl.h"
const char tls1_version_str[]="TLSv1" OPENSSL_VERSION_PTEXT;
#ifndef OPENSSL_NO_TLSEXT
static int tls_decrypt_ticket(SSL *s, const unsigned char *tick, int ticklen,
const unsigned char *sess_id, int sesslen,
SSL_SESSION **psess);
#endif
SSL3_ENC_METHOD TLSv1_enc_data={
tls1_enc,
tls1_mac,
tls1_setup_key_block,
tls1_generate_master_secret,
tls1_change_cipher_state,
tls1_final_finish_mac,
TLS1_FINISH_MAC_LENGTH,
tls1_cert_verify_mac,
TLS_MD_CLIENT_FINISH_CONST,TLS_MD_CLIENT_FINISH_CONST_SIZE,
TLS_MD_SERVER_FINISH_CONST,TLS_MD_SERVER_FINISH_CONST_SIZE,
tls1_alert_code,
};
long tls1_default_timeout(void)
{
/* 2 hours, the 24 hours mentioned in the TLSv1 spec
* is way too long for http, the cache would over fill */
return(60*60*2);
}
IMPLEMENT_tls1_meth_func(tlsv1_base_method,
ssl_undefined_function,
ssl_undefined_function,
ssl_bad_method)
int tls1_new(SSL *s)
{
if (!ssl3_new(s)) return(0);
s->method->ssl_clear(s);
return(1);
}
void tls1_free(SSL *s)
{
ssl3_free(s);
}
void tls1_clear(SSL *s)
{
ssl3_clear(s);
s->version=TLS1_VERSION;
}
#if 0
long tls1_ctrl(SSL *s, int cmd, long larg, char *parg)
{
return(0);
}
long tls1_callback_ctrl(SSL *s, int cmd, void *(*fp)())
{
return(0);
}
#endif
#ifndef OPENSSL_NO_TLSEXT
unsigned char *ssl_add_clienthello_tlsext(SSL *s, unsigned char *p, unsigned char *limit)
{
int extdatalen=0;
unsigned char *ret = p;
ret+=2;
if (ret>=limit) return NULL; /* this really never occurs, but ... */
if (s->tlsext_hostname != NULL)
{
/* Add TLS extension servername to the Client Hello message */
unsigned long size_str;
long lenmax;
/* check for enough space.
4 for the servername type and entension length
2 for servernamelist length
1 for the hostname type
2 for hostname length
+ hostname length
*/
if ((lenmax = limit - ret - 9) < 0
|| (size_str = strlen(s->tlsext_hostname)) > (unsigned long)lenmax)
return NULL;
/* extension type and length */
s2n(TLSEXT_TYPE_server_name,ret);
s2n(size_str+5,ret);
/* length of servername list */
s2n(size_str+3,ret);
/* hostname type, length and hostname */
*(ret++) = (unsigned char) TLSEXT_NAMETYPE_host_name;
s2n(size_str,ret);
memcpy(ret, s->tlsext_hostname, size_str);
ret+=size_str;
}
if (!(SSL_get_options(s) & SSL_OP_NO_TICKET))
{
int ticklen;
if (s->session && s->session->tlsext_tick)
ticklen = s->session->tlsext_ticklen;
else
ticklen = 0;
/* Check for enough room 2 for extension type, 2 for len
* rest for ticket
*/
if (limit - ret - 4 - ticklen < 0)
return NULL;
s2n(TLSEXT_TYPE_session_ticket,ret);
s2n(ticklen,ret);
if (ticklen)
{
memcpy(ret, s->session->tlsext_tick, ticklen);
ret += ticklen;
}
}
if ((extdatalen = ret-p-2)== 0)
return p;
s2n(extdatalen,p);
return ret;
}
unsigned char *ssl_add_serverhello_tlsext(SSL *s, unsigned char *p, unsigned char *limit)
{
int extdatalen=0;
unsigned char *ret = p;
ret+=2;
if (ret>=limit) return NULL; /* this really never occurs, but ... */
if (!s->hit && s->servername_done == 1 && s->session->tlsext_hostname != NULL)
{
if (limit - ret - 4 < 0) return NULL;
s2n(TLSEXT_TYPE_server_name,ret);
s2n(0,ret);
}
if (s->tlsext_ticket_expected
&& !(SSL_get_options(s) & SSL_OP_NO_TICKET))
{
if (limit - ret - 4 < 0) return NULL;
s2n(TLSEXT_TYPE_session_ticket,ret);
s2n(0,ret);
}
if ((extdatalen = ret-p-2)== 0)
return p;
s2n(extdatalen,p);
return ret;
}
int ssl_parse_clienthello_tlsext(SSL *s, unsigned char **p, unsigned char *d, int n, int *al)
{
unsigned short type;
unsigned short size;
unsigned short len;
unsigned char *data = *p;
s->servername_done = 0;
if (data >= (d+n-2))
return 1;
n2s(data,len);
if (data > (d+n-len))
return 1;
while (data <= (d+n-4))
{
n2s(data,type);
n2s(data,size);
if (data+size > (d+n))
return 1;
if (s->tlsext_debug_cb)
s->tlsext_debug_cb(s, 0, type, data, size,
s->tlsext_debug_arg);
/* The servername extension is treated as follows:
- Only the hostname type is supported with a maximum length of 255.
- The servername is rejected if too long or if it contains zeros,
in which case an fatal alert is generated.
- The servername field is maintained together with the session cache.
- When a session is resumed, the servername call back invoked in order
to allow the application to position itself to the right context.
- The servername is acknowledged if it is new for a session or when
it is identical to a previously used for the same session.
Applications can control the behaviour. They can at any time
set a 'desirable' servername for a new SSL object. This can be the
case for example with HTTPS when a Host: header field is received and
a renegotiation is requested. In this case, a possible servername
presented in the new client hello is only acknowledged if it matches
the value of the Host: field.
- Applications must use SSL_OP_NO_SESSION_RESUMPTION_ON_RENEGOTIATION
if they provide for changing an explicit servername context for the session,
i.e. when the session has been established with a servername extension.
- On session reconnect, the servername extension may be absent.
*/
if (type == TLSEXT_TYPE_server_name)
{
unsigned char *sdata;
int servname_type;
int dsize;
if (size < 2)
{
*al = SSL_AD_DECODE_ERROR;
return 0;
}
n2s(data,dsize);
size -= 2;
if (dsize > size )
{
*al = SSL_AD_DECODE_ERROR;
return 0;
}
sdata = data;
while (dsize > 3)
{
servname_type = *(sdata++);
n2s(sdata,len);
dsize -= 3;
if (len > dsize)
{
*al = SSL_AD_DECODE_ERROR;
return 0;
}
if (s->servername_done == 0)
switch (servname_type)
{
case TLSEXT_NAMETYPE_host_name:
if (s->session->tlsext_hostname == NULL)
{
if (len > TLSEXT_MAXLEN_host_name ||
((s->session->tlsext_hostname = OPENSSL_malloc(len+1)) == NULL))
{
*al = TLS1_AD_UNRECOGNIZED_NAME;
return 0;
}
memcpy(s->session->tlsext_hostname, sdata, len);
s->session->tlsext_hostname[len]='\0';
if (strlen(s->session->tlsext_hostname) != len) {
OPENSSL_free(s->session->tlsext_hostname);
*al = TLS1_AD_UNRECOGNIZED_NAME;
return 0;
}
s->servername_done = 1;
}
else
s->servername_done = strlen(s->session->tlsext_hostname) == len
&& strncmp(s->session->tlsext_hostname, (char *)sdata, len) == 0;
break;
default:
break;
}
dsize -= len;
}
if (dsize != 0)
{
*al = SSL_AD_DECODE_ERROR;
return 0;
}
}
/* session ticket processed earlier */
data+=size;
}
*p = data;
return 1;
}
int ssl_parse_serverhello_tlsext(SSL *s, unsigned char **p, unsigned char *d, int n, int *al)
{
unsigned short type;
unsigned short size;
unsigned short len;
unsigned char *data = *p;
int tlsext_servername = 0;
if (data >= (d+n-2))
return 1;
n2s(data,len);
while(data <= (d+n-4))
{
n2s(data,type);
n2s(data,size);
if (data+size > (d+n))
return 1;
if (s->tlsext_debug_cb)
s->tlsext_debug_cb(s, 1, type, data, size,
s->tlsext_debug_arg);
if (type == TLSEXT_TYPE_server_name)
{
if (s->tlsext_hostname == NULL || size > 0)
{
*al = TLS1_AD_UNRECOGNIZED_NAME;
return 0;
}
tlsext_servername = 1;
}
else if (type == TLSEXT_TYPE_session_ticket)
{
if ((SSL_get_options(s) & SSL_OP_NO_TICKET)
|| (size > 0))
{
*al = TLS1_AD_UNSUPPORTED_EXTENSION;
return 0;
}
s->tlsext_ticket_expected = 1;
}
data+=size;
}
if (data != d+n)
{
*al = SSL_AD_DECODE_ERROR;
return 0;
}
if (!s->hit && tlsext_servername == 1)
{
if (s->tlsext_hostname)
{
if (s->session->tlsext_hostname == NULL)
{
s->session->tlsext_hostname = BUF_strdup(s->tlsext_hostname);
if (!s->session->tlsext_hostname)
{
*al = SSL_AD_UNRECOGNIZED_NAME;
return 0;
}
}
else
{
*al = SSL_AD_DECODE_ERROR;
return 0;
}
}
}
*p = data;
return 1;
}
int ssl_check_clienthello_tlsext(SSL *s)
{
int ret=SSL_TLSEXT_ERR_NOACK;
int al = SSL_AD_UNRECOGNIZED_NAME;
if (s->ctx != NULL && s->ctx->tlsext_servername_callback != 0)
ret = s->ctx->tlsext_servername_callback(s, &al, s->ctx->tlsext_servername_arg);
else if (s->initial_ctx != NULL && s->initial_ctx->tlsext_servername_callback != 0)
ret = s->initial_ctx->tlsext_servername_callback(s, &al, s->initial_ctx->tlsext_servername_arg);
switch (ret)
{
case SSL_TLSEXT_ERR_ALERT_FATAL:
ssl3_send_alert(s,SSL3_AL_FATAL,al);
return -1;
case SSL_TLSEXT_ERR_ALERT_WARNING:
ssl3_send_alert(s,SSL3_AL_WARNING,al);
return 1;
case SSL_TLSEXT_ERR_NOACK:
s->servername_done=0;
default:
return 1;
}
}
int ssl_check_serverhello_tlsext(SSL *s)
{
int ret=SSL_TLSEXT_ERR_NOACK;
int al = SSL_AD_UNRECOGNIZED_NAME;
if (s->ctx != NULL && s->ctx->tlsext_servername_callback != 0)
ret = s->ctx->tlsext_servername_callback(s, &al, s->ctx->tlsext_servername_arg);
else if (s->initial_ctx != NULL && s->initial_ctx->tlsext_servername_callback != 0)
ret = s->initial_ctx->tlsext_servername_callback(s, &al, s->initial_ctx->tlsext_servername_arg);
switch (ret)
{
case SSL_TLSEXT_ERR_ALERT_FATAL:
ssl3_send_alert(s,SSL3_AL_FATAL,al);
return -1;
case SSL_TLSEXT_ERR_ALERT_WARNING:
ssl3_send_alert(s,SSL3_AL_WARNING,al);
return 1;
case SSL_TLSEXT_ERR_NOACK:
s->servername_done=0;
default:
return 1;
}
}
/* Since the server cache lookup is done early on in the processing of client
* hello and other operations depend on the result we need to handle any TLS
* session ticket extension at the same time.
*/
int tls1_process_ticket(SSL *s, unsigned char *session_id, int len,
const unsigned char *limit, SSL_SESSION **ret)
{
/* Point after session ID in client hello */
const unsigned char *p = session_id + len;
unsigned short i;
if ((s->version <= SSL3_VERSION) || !limit)
return 1;
if (p >= limit)
return -1;
/* Skip past cipher list */
n2s(p, i);
p+= i;
if (p >= limit)
return -1;
/* Skip past compression algorithm list */
i = *(p++);
p += i;
if (p > limit)
return -1;
/* Now at start of extensions */
if ((p + 2) >= limit)
return 1;
n2s(p, i);
while ((p + 4) <= limit)
{
unsigned short type, size;
n2s(p, type);
n2s(p, size);
if (p + size > limit)
return 1;
if (type == TLSEXT_TYPE_session_ticket)
{
/* If tickets disabled indicate cache miss which will
* trigger a full handshake
*/
if (SSL_get_options(s) & SSL_OP_NO_TICKET)
return 0;
/* If zero length not client will accept a ticket
* and indicate cache miss to trigger full handshake
*/
if (size == 0)
{
s->tlsext_ticket_expected = 1;
return 0; /* Cache miss */
}
return tls_decrypt_ticket(s, p, size, session_id, len,
ret);
}
p += size;
}
return 1;
}
static int tls_decrypt_ticket(SSL *s, const unsigned char *etick, int eticklen,
const unsigned char *sess_id, int sesslen,
SSL_SESSION **psess)
{
SSL_SESSION *sess;
unsigned char *sdec;
const unsigned char *p;
int slen, mlen;
unsigned char tick_hmac[EVP_MAX_MD_SIZE];
HMAC_CTX hctx;
EVP_CIPHER_CTX ctx;
/* Attempt to process session ticket, first conduct sanity and
* integrity checks on ticket.
*/
mlen = EVP_MD_size(tlsext_tick_md());
eticklen -= mlen;
/* Need at least keyname + iv + some encrypted data */
if (eticklen < 48)
goto tickerr;
/* Check key name matches */
if (memcmp(etick, s->ctx->tlsext_tick_key_name, 16))
goto tickerr;
/* Check HMAC of encrypted ticket */
HMAC_CTX_init(&hctx);
HMAC_Init_ex(&hctx, s->ctx->tlsext_tick_hmac_key, 16,
tlsext_tick_md(), NULL);
HMAC_Update(&hctx, etick, eticklen);
HMAC_Final(&hctx, tick_hmac, NULL);
HMAC_CTX_cleanup(&hctx);
if (memcmp(tick_hmac, etick + eticklen, mlen))
goto tickerr;
/* Set p to start of IV */
p = etick + 16;
EVP_CIPHER_CTX_init(&ctx);
/* Attempt to decrypt session data */
EVP_DecryptInit_ex(&ctx, EVP_aes_128_cbc(), NULL,
s->ctx->tlsext_tick_aes_key, p);
/* Move p after IV to start of encrypted ticket, update length */
p += 16;
eticklen -= 32;
sdec = OPENSSL_malloc(eticklen);
if (!sdec)
{
EVP_CIPHER_CTX_cleanup(&ctx);
return -1;
}
EVP_DecryptUpdate(&ctx, sdec, &slen, p, eticklen);
if (EVP_DecryptFinal(&ctx, sdec + slen, &mlen) <= 0)
goto tickerr;
slen += mlen;
EVP_CIPHER_CTX_cleanup(&ctx);
p = sdec;
sess = d2i_SSL_SESSION(NULL, &p, slen);
OPENSSL_free(sdec);
if (sess)
{
/* The session ID if non-empty is used by some clients to
* detect that the ticket has been accepted. So we copy it to
* the session structure. If it is empty set length to zero
* as required by standard.
*/
if (sesslen)
memcpy(sess->session_id, sess_id, sesslen);
sess->session_id_length = sesslen;
*psess = sess;
s->tlsext_ticket_expected = 0;
return 1;
}
/* If session decrypt failure indicate a cache miss and set state to
* send a new ticket
*/
tickerr:
s->tlsext_ticket_expected = 1;
return 0;
}
#endif
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