1: /* ssl/t1_lib.c */
    2: /* Copyright (C) 1995-1998 Eric Young (eay@cryptsoft.com)
    3:  * All rights reserved.
    4:  *
    5:  * This package is an SSL implementation written
    6:  * by Eric Young (eay@cryptsoft.com).
    7:  * The implementation was written so as to conform with Netscapes SSL.
    8:  * 
    9:  * This library is free for commercial and non-commercial use as long as
   10:  * the following conditions are aheared to.  The following conditions
   11:  * apply to all code found in this distribution, be it the RC4, RSA,
   12:  * lhash, DES, etc., code; not just the SSL code.  The SSL documentation
   13:  * included with this distribution is covered by the same copyright terms
   14:  * except that the holder is Tim Hudson (tjh@cryptsoft.com).
   15:  * 
   16:  * Copyright remains Eric Young's, and as such any Copyright notices in
   17:  * the code are not to be removed.
   18:  * If this package is used in a product, Eric Young should be given attribution
   19:  * as the author of the parts of the library used.
   20:  * This can be in the form of a textual message at program startup or
   21:  * in documentation (online or textual) provided with the package.
   22:  * 
   23:  * Redistribution and use in source and binary forms, with or without
   24:  * modification, are permitted provided that the following conditions
   25:  * are met:
   26:  * 1. Redistributions of source code must retain the copyright
   27:  *    notice, this list of conditions and the following disclaimer.
   28:  * 2. Redistributions in binary form must reproduce the above copyright
   29:  *    notice, this list of conditions and the following disclaimer in the
   30:  *    documentation and/or other materials provided with the distribution.
   31:  * 3. All advertising materials mentioning features or use of this software
   32:  *    must display the following acknowledgement:
   33:  *    "This product includes cryptographic software written by
   34:  *     Eric Young (eay@cryptsoft.com)"
   35:  *    The word 'cryptographic' can be left out if the rouines from the library
   36:  *    being used are not cryptographic related :-).
   37:  * 4. If you include any Windows specific code (or a derivative thereof) from 
   38:  *    the apps directory (application code) you must include an acknowledgement:
   39:  *    "This product includes software written by Tim Hudson (tjh@cryptsoft.com)"
   40:  * 
   41:  * THIS SOFTWARE IS PROVIDED BY ERIC YOUNG ``AS IS'' AND
   42:  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
   43:  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
   44:  * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
   45:  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
   46:  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
   47:  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
   48:  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
   49:  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
   50:  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
   51:  * SUCH DAMAGE.
   52:  * 
   53:  * The licence and distribution terms for any publically available version or
   54:  * derivative of this code cannot be changed.  i.e. this code cannot simply be
   55:  * copied and put under another distribution licence
   56:  * [including the GNU Public Licence.]
   57:  */
   58: 
   59: #include <stdio.h>
   60: #include <openssl/objects.h>
   61: #include <openssl/evp.h>
   62: #include <openssl/hmac.h>
   63: #include "ssl_locl.h"
   64: 
   65: const char tls1_version_str[]="TLSv1" OPENSSL_VERSION_PTEXT;
   66: 
   67: #ifndef OPENSSL_NO_TLSEXT
   68: static int tls_decrypt_ticket(SSL *s, const unsigned char *tick, int ticklen,
   69:                                 const unsigned char *sess_id, int sesslen,
   70:                                 SSL_SESSION **psess);
   71: #endif
   72: 
   73: SSL3_ENC_METHOD TLSv1_enc_data={
   74:         tls1_enc,
   75:         tls1_mac,
   76:         tls1_setup_key_block,
   77:         tls1_generate_master_secret,
   78:         tls1_change_cipher_state,
   79:         tls1_final_finish_mac,
   80:         TLS1_FINISH_MAC_LENGTH,
   81:         tls1_cert_verify_mac,
   82:         TLS_MD_CLIENT_FINISH_CONST,TLS_MD_CLIENT_FINISH_CONST_SIZE,
   83:         TLS_MD_SERVER_FINISH_CONST,TLS_MD_SERVER_FINISH_CONST_SIZE,
   84:         tls1_alert_code,
   85:         };
   86: 
   87: long tls1_default_timeout(void)
   88:         {
   89:         /* 2 hours, the 24 hours mentioned in the TLSv1 spec
   90:          * is way too long for http, the cache would over fill */
   91:         return(60*60*2);
   92:         }
   93: 
   94: IMPLEMENT_tls1_meth_func(tlsv1_base_method,
   95:                         ssl_undefined_function,
   96:                         ssl_undefined_function,
   97:                         ssl_bad_method)
   98: 
   99: int tls1_new(SSL *s)
  100:         {
  101:         if (!ssl3_new(s)) return(0);
  102:         s->method->ssl_clear(s);
  103:         return(1);
  104:         }
  105: 
  106: void tls1_free(SSL *s)
  107:         {
  108:         ssl3_free(s);
  109:         }
  110: 
  111: void tls1_clear(SSL *s)
  112:         {
  113:         ssl3_clear(s);
  114:         s->version=TLS1_VERSION;
  115:         }
  116: 
  117: #if 0
  118: long tls1_ctrl(SSL *s, int cmd, long larg, char *parg)
  119:         {
  120:         return(0);
  121:         }
  122: 
  123: long tls1_callback_ctrl(SSL *s, int cmd, void *(*fp)())
  124:         {
  125:         return(0);
  126:         }
  127: #endif
  128: 
  129: #ifndef OPENSSL_NO_TLSEXT
  130: unsigned char *ssl_add_clienthello_tlsext(SSL *s, unsigned char *p, unsigned char *limit)
  131:         {
  132:         int extdatalen=0;
  133:         unsigned char *ret = p;
  134: 
  135:         ret+=2;
  136: 
  137:         if (ret>=limit) return NULL; /* this really never occurs, but ... */
  138: 
  139:         if (s->tlsext_hostname != NULL)
  140:                 { 
  141:                 /* Add TLS extension servername to the Client Hello message */
  142:                 unsigned long size_str;
  143:                 long lenmax; 
  144: 
  145:                 /* check for enough space.
  146:                    4 for the servername type and entension length
  147:                    2 for servernamelist length
  148:                    1 for the hostname type
  149:                    2 for hostname length
  150:                    + hostname length 
  151:                 */
  152:                    
  153:                 if ((lenmax = limit - ret - 9) < 0 
  154:                 || (size_str = strlen(s->tlsext_hostname)) > (unsigned long)lenmax) 
  155:                         return NULL;
  156:                         
  157:                 /* extension type and length */
  158:                 s2n(TLSEXT_TYPE_server_name,ret); 
  159:                 s2n(size_str+5,ret);
  160:                 
  161:                 /* length of servername list */
  162:                 s2n(size_str+3,ret);
  163:         
  164:                 /* hostname type, length and hostname */
  165:                 *(ret++) = (unsigned char) TLSEXT_NAMETYPE_host_name;
  166:                 s2n(size_str,ret);
  167:                 memcpy(ret, s->tlsext_hostname, size_str);
  168:                 ret+=size_str;
  169: 
  170:                 }
  171: 
  172:         if (!(SSL_get_options(s) & SSL_OP_NO_TICKET))
  173:                 {
  174:                 int ticklen;
  175:                 if (s->session && s->session->tlsext_tick)
  176:                         ticklen = s->session->tlsext_ticklen;
  177:                 else
  178:                         ticklen = 0;
  179:                 /* Check for enough room 2 for extension type, 2 for len
  180:                  * rest for ticket
  181:                  */
  182:                 if (limit - ret - 4 - ticklen < 0)
  183:                         return NULL;
  184:                 s2n(TLSEXT_TYPE_session_ticket,ret); 
  185:                 s2n(ticklen,ret);
  186:                 if (ticklen)
  187:                         {
  188:                         memcpy(ret, s->session->tlsext_tick, ticklen);
  189:                         ret += ticklen;
  190:                         }
  191:                 }
  192: 
  193:         if ((extdatalen = ret-p-2)== 0) 
  194:                 return p;
  195: 
  196:         s2n(extdatalen,p);
  197:         return ret;
  198:         }
  199: 
  200: unsigned char *ssl_add_serverhello_tlsext(SSL *s, unsigned char *p, unsigned char *limit)
  201:         {
  202:         int extdatalen=0;
  203:         unsigned char *ret = p;
  204: 
  205:         ret+=2;
  206:         if (ret>=limit) return NULL; /* this really never occurs, but ... */
  207: 
  208:         if (!s->hit && s->servername_done == 1 && s->session->tlsext_hostname != NULL)
  209:                 { 
  210:                 if (limit - ret - 4 < 0) return NULL; 
  211: 
  212:                 s2n(TLSEXT_TYPE_server_name,ret);
  213:                 s2n(0,ret);
  214:                 }
  215:         
  216:         if (s->tlsext_ticket_expected
  217:                 && !(SSL_get_options(s) & SSL_OP_NO_TICKET)) 
  218:                 { 
  219:                 if (limit - ret - 4 < 0) return NULL; 
  220:                 s2n(TLSEXT_TYPE_session_ticket,ret);
  221:                 s2n(0,ret);
  222:                 }
  223:                 
  224:         if ((extdatalen = ret-p-2)== 0) 
  225:                 return p;
  226: 
  227:         s2n(extdatalen,p);
  228:         return ret;
  229:         }
  230: 
  231: int ssl_parse_clienthello_tlsext(SSL *s, unsigned char **p, unsigned char *d, int n, int *al)
  232:         {
  233:         unsigned short type;
  234:         unsigned short size;
  235:         unsigned short len;
  236:         unsigned char *data = *p;
  237:         s->servername_done = 0;
  238: 
  239:         if (data >= (d+n-2))
  240:                 return 1;
  241:         n2s(data,len);
  242: 
  243:         if (data > (d+n-len)) 
  244:                 return 1;
  245: 
  246:         while (data <= (d+n-4))
  247:                 {
  248:                 n2s(data,type);
  249:                 n2s(data,size);
  250: 
  251:                 if (data+size > (d+n))
  252:                        return 1;
  253: 
  254:                 if (s->tlsext_debug_cb)
  255:                         s->tlsext_debug_cb(s, 0, type, data, size,
  256:                                                 s->tlsext_debug_arg);
  257: /* The servername extension is treated as follows:
  258: 
  259:    - Only the hostname type is supported with a maximum length of 255.
  260:    - The servername is rejected if too long or if it contains zeros,
  261:      in which case an fatal alert is generated.
  262:    - The servername field is maintained together with the session cache.
  263:    - When a session is resumed, the servername call back invoked in order
  264:      to allow the application to position itself to the right context. 
  265:    - The servername is acknowledged if it is new for a session or when 
  266:      it is identical to a previously used for the same session. 
  267:      Applications can control the behaviour.  They can at any time
  268:      set a 'desirable' servername for a new SSL object. This can be the
  269:      case for example with HTTPS when a Host: header field is received and
  270:      a renegotiation is requested. In this case, a possible servername
  271:      presented in the new client hello is only acknowledged if it matches
  272:      the value of the Host: field. 
  273:    - Applications must  use SSL_OP_NO_SESSION_RESUMPTION_ON_RENEGOTIATION
  274:      if they provide for changing an explicit servername context for the session,
  275:      i.e. when the session has been established with a servername extension. 
  276:    - On session reconnect, the servername extension may be absent. 
  277: 
  278: */      
  279: 
  280:                 if (type == TLSEXT_TYPE_server_name)
  281:                         {
  282:                         unsigned char *sdata;
  283:                         int servname_type;
  284:                         int dsize; 
  285:                 
  286:                         if (size < 2) 
  287:                                 {
  288:                                 *al = SSL_AD_DECODE_ERROR;
  289:                                 return 0;
  290:                                 }
  291:                         n2s(data,dsize);  
  292:                         size -= 2;
  293:                         if (dsize > size  ) 
  294:                                 {
  295:                                 *al = SSL_AD_DECODE_ERROR;
  296:                                 return 0;
  297:                                 } 
  298: 
  299:                         sdata = data;
  300:                         while (dsize > 3) 
  301:                                 {
  302:                                servname_type = *(sdata++); 
  303:                                 n2s(sdata,len);
  304:                                 dsize -= 3;
  305: 
  306:                                 if (len > dsize) 
  307:                                         {
  308:                                         *al = SSL_AD_DECODE_ERROR;
  309:                                         return 0;
  310:                                         }
  311:                                 if (s->servername_done == 0)
  312:                                 switch (servname_type)
  313:                                         {
  314:                                 case TLSEXT_NAMETYPE_host_name:
  315:                                         if (s->session->tlsext_hostname == NULL)
  316:                                                 {
  317:                                                 if (len > TLSEXT_MAXLEN_host_name || 
  318:                                                         ((s->session->tlsext_hostname = OPENSSL_malloc(len+1)) == NULL))
  319:                                                         {
  320:                                                         *al = TLS1_AD_UNRECOGNIZED_NAME;
  321:                                                         return 0;
  322:                                                         }
  323:                                                 memcpy(s->session->tlsext_hostname, sdata, len);
  324:                                                 s->session->tlsext_hostname[len]='\0';
  325:                                                 if (strlen(s->session->tlsext_hostname) != len) {
  326:                                                         OPENSSL_free(s->session->tlsext_hostname);
  327:                                                         *al = TLS1_AD_UNRECOGNIZED_NAME;
  328:                                                         return 0;
  329:                                                 }
  330:                                                 s->servername_done = 1; 
  331: 
  332:                                                 }
  333:                                         else 
  334:                                                 s->servername_done = strlen(s->session->tlsext_hostname) == len 
  335:                                                         && strncmp(s->session->tlsext_hostname, (char *)sdata, len) == 0;
  336:                                         
  337:                                         break;
  338: 
  339:                                 default:
  340:                                         break;
  341:                                         }
  342:                                  
  343:                                 dsize -= len;
  344:                                 }
  345:                         if (dsize != 0) 
  346:                                 {
  347:                                 *al = SSL_AD_DECODE_ERROR;
  348:                                 return 0;
  349:                                 }
  350: 
  351:                         }
  352:                 /* session ticket processed earlier */
  353: 
  354:                 data+=size;           
  355:                 }
  356: 
  357:         *p = data;
  358:         return 1;
  359:         }
  360: 
  361: int ssl_parse_serverhello_tlsext(SSL *s, unsigned char **p, unsigned char *d, int n, int *al)
  362:         {
  363:         unsigned short type;
  364:         unsigned short size;
  365:         unsigned short len;  
  366:         unsigned char *data = *p;
  367: 
  368:         int tlsext_servername = 0;
  369: 
  370:         if (data >= (d+n-2))
  371:                 return 1;
  372: 
  373:         n2s(data,len);
  374: 
  375:         while(data <= (d+n-4))
  376:                 {
  377:                 n2s(data,type);
  378:                 n2s(data,size);
  379: 
  380:                 if (data+size > (d+n))
  381:                        return 1;
  382: 
  383:                 if (s->tlsext_debug_cb)
  384:                         s->tlsext_debug_cb(s, 1, type, data, size,
  385:                                                 s->tlsext_debug_arg);
  386: 
  387:                 if (type == TLSEXT_TYPE_server_name)
  388:                         {
  389:                         if (s->tlsext_hostname == NULL || size > 0)
  390:                                 {
  391:                                 *al = TLS1_AD_UNRECOGNIZED_NAME;
  392:                                 return 0;
  393:                                 }
  394:                         tlsext_servername = 1;   
  395:                         }
  396:                 else if (type == TLSEXT_TYPE_session_ticket)
  397:                         {
  398:                         if ((SSL_get_options(s) & SSL_OP_NO_TICKET)
  399:                                 || (size > 0))
  400:                                 {
  401:                                 *al = TLS1_AD_UNSUPPORTED_EXTENSION;
  402:                                 return 0;
  403:                                 }
  404:                         s->tlsext_ticket_expected = 1;
  405:                         }
  406: 
  407:                 data+=size;           
  408:                 }
  409: 
  410:         if (data != d+n)
  411:                 {
  412:                 *al = SSL_AD_DECODE_ERROR;
  413:                 return 0;
  414:                 }
  415: 
  416:         if (!s->hit && tlsext_servername == 1)
  417:                 {
  418:                 if (s->tlsext_hostname)
  419:                         {
  420:                         if (s->session->tlsext_hostname == NULL)
  421:                                 {
  422:                                 s->session->tlsext_hostname = BUF_strdup(s->tlsext_hostname);       
  423:                                 if (!s->session->tlsext_hostname)
  424:                                         {
  425:                                         *al = SSL_AD_UNRECOGNIZED_NAME;
  426:                                         return 0;
  427:                                         }
  428:                                 }
  429:                         else 
  430:                                 {
  431:                                 *al = SSL_AD_DECODE_ERROR;
  432:                                 return 0;
  433:                                 }
  434:                         }
  435:                 }
  436: 
  437:         *p = data;
  438:         return 1;
  439:         }
  440: 
  441: int ssl_check_clienthello_tlsext(SSL *s)
  442:         {
  443:         int ret=SSL_TLSEXT_ERR_NOACK;
  444:         int al = SSL_AD_UNRECOGNIZED_NAME;
  445: 
  446:         if (s->ctx != NULL && s->ctx->tlsext_servername_callback != 0) 
  447:                 ret = s->ctx->tlsext_servername_callback(s, &al, s->ctx->tlsext_servername_arg);
  448:         else if (s->initial_ctx != NULL && s->initial_ctx->tlsext_servername_callback != 0)            
  449:                 ret = s->initial_ctx->tlsext_servername_callback(s, &al, s->initial_ctx->tlsext_servername_arg);
  450: 
  451:         switch (ret)
  452:                 {
  453:                 case SSL_TLSEXT_ERR_ALERT_FATAL:
  454:                         ssl3_send_alert(s,SSL3_AL_FATAL,al); 
  455:                         return -1;
  456: 
  457:                 case SSL_TLSEXT_ERR_ALERT_WARNING:
  458:                         ssl3_send_alert(s,SSL3_AL_WARNING,al);
  459:                         return 1; 
  460:                                         
  461:                 case SSL_TLSEXT_ERR_NOACK:
  462:                         s->servername_done=0;
  463:                         default:
  464:                 return 1;
  465:                 }
  466:         }
  467: 
  468: int ssl_check_serverhello_tlsext(SSL *s)
  469:         {
  470:         int ret=SSL_TLSEXT_ERR_NOACK;
  471:         int al = SSL_AD_UNRECOGNIZED_NAME;
  472: 
  473:         if (s->ctx != NULL && s->ctx->tlsext_servername_callback != 0) 
  474:                 ret = s->ctx->tlsext_servername_callback(s, &al, s->ctx->tlsext_servername_arg);
  475:         else if (s->initial_ctx != NULL && s->initial_ctx->tlsext_servername_callback != 0)            
  476:                 ret = s->initial_ctx->tlsext_servername_callback(s, &al, s->initial_ctx->tlsext_servername_arg);
  477: 
  478:         switch (ret)
  479:                 {
  480:                 case SSL_TLSEXT_ERR_ALERT_FATAL:
  481:                         ssl3_send_alert(s,SSL3_AL_FATAL,al); 
  482:                         return -1;
  483: 
  484:                 case SSL_TLSEXT_ERR_ALERT_WARNING:
  485:                         ssl3_send_alert(s,SSL3_AL_WARNING,al);
  486:                         return 1; 
  487:                                         
  488:                 case SSL_TLSEXT_ERR_NOACK:
  489:                         s->servername_done=0;
  490:                         default:
  491:                 return 1;
  492:                 }
  493:         }
  494: 
  495: /* Since the server cache lookup is done early on in the processing of client
  496:  * hello and other operations depend on the result we need to handle any TLS
  497:  * session ticket extension at the same time.
  498:  */
  499: 
  500: int tls1_process_ticket(SSL *s, unsigned char *session_id, int len,
  501:                                 const unsigned char *limit, SSL_SESSION **ret)
  502:         {
  503:         /* Point after session ID in client hello */
  504:         const unsigned char *p = session_id + len;
  505:         unsigned short i;
  506:         if ((s->version <= SSL3_VERSION) || !limit)
  507:                 return 1;
  508:         if (p >= limit)
  509:                 return -1;
  510:         /* Skip past cipher list */
  511:         n2s(p, i);
  512:         p+= i;
  513:         if (p >= limit)
  514:                 return -1;
  515:         /* Skip past compression algorithm list */
  516:         i = *(p++);
  517:         p += i;
  518:         if (p > limit)
  519:                 return -1;
  520:         /* Now at start of extensions */
  521:         if ((p + 2) >= limit)
  522:                 return 1;
  523:         n2s(p, i);
  524:         while ((p + 4) <= limit)
  525:                 {
  526:                 unsigned short type, size;
  527:                 n2s(p, type);
  528:                 n2s(p, size);
  529:                 if (p + size > limit)
  530:                         return 1;
  531:                 if (type == TLSEXT_TYPE_session_ticket)
  532:                         {
  533:                         /* If tickets disabled indicate cache miss which will
  534:                          * trigger a full handshake
  535:                          */
  536:                         if (SSL_get_options(s) & SSL_OP_NO_TICKET)
  537:                                 return 0;
  538:                         /* If zero length not client will accept a ticket
  539:                          * and indicate cache miss to trigger full handshake
  540:                          */
  541:                         if (size == 0)
  542:                                 {
  543:                                 s->tlsext_ticket_expected = 1;
  544:                                 return 0;   /* Cache miss */
  545:                                 }
  546:                         return tls_decrypt_ticket(s, p, size, session_id, len,
  547:                                                                         ret);
  548:                         }
  549:                 p += size;
  550:                 }
  551:         return 1;
  552:         }
  553: 
  554: static int tls_decrypt_ticket(SSL *s, const unsigned char *etick, int eticklen,
  555:                                 const unsigned char *sess_id, int sesslen,
  556:                                 SSL_SESSION **psess)
  557:         {
  558:         SSL_SESSION *sess;
  559:         unsigned char *sdec;
  560:         const unsigned char *p;
  561:         int slen, mlen;
  562:         unsigned char tick_hmac[EVP_MAX_MD_SIZE];
  563:         HMAC_CTX hctx;
  564:         EVP_CIPHER_CTX ctx;
  565:         /* Attempt to process session ticket, first conduct sanity and
  566:          * integrity checks on ticket.
  567:          */
  568:         mlen = EVP_MD_size(tlsext_tick_md());
  569:         eticklen -= mlen;
  570:         /* Need at least keyname + iv + some encrypted data */
<