src/core/sip-sec-tls-dsk.c

   1 /**
   2  * @file sip-sec-tls-dsk.c
   3  *
   4  * pidgin-sipe
   5  *
   6  * Copyright (C) 2011-2013 SIPE Project <http://sipe.sourceforge.net/>
   7  *
   8  *
   9  * This program is free software; you can redistribute it and/or modify
  10  * it under the terms of the GNU General Public License as published by
  11  * the Free Software Foundation; either version 2 of the License, or
  12  * (at your option) any later version.
  13  *
  14  * This program is distributed in the hope that it will be useful,
  15  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  16  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  17  * GNU General Public License for more details.
  18  *
  19  * You should have received a copy of the GNU General Public License
  20  * along with this program; if not, write to the Free Software
  21  * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
  22  *
  23  *
  24  * Specification references:
  25  *
  26  *   - [MS-SIPAE]:    http://msdn.microsoft.com/en-us/library/cc431510.aspx
  27  *   - [MS-OCAUTHWS]: http://msdn.microsoft.com/en-us/library/ff595592.aspx
  28  *   - MS Tech-Ed Europe 2010 "UNC310: Microsoft Lync 2010 Technology Explained"
  29  *     http://ecn.channel9.msdn.com/o9/te/Europe/2010/pptx/unc310.pptx
  30  */
  31
  32 #include <string.h>
  33
  34 #include <glib.h>
  35
  36 #include "sipe-common.h"
  37 #include "sip-sec.h"
  38 #include "sip-sec-mech.h"
  39 #include "sip-sec-tls-dsk.h"
  40 #include "sipe-backend.h"
  41 #include "sipe-digest.h"
  42 #include "sipe-tls.h"
  43
  44 /* Security context for TLS-DSK */
  45 typedef struct _context_tls_dsk {
  46         struct sip_sec_context common;
  47         struct sipe_tls_state *state;
  48         enum sipe_tls_digest_algorithm algorithm;
  49         guchar *client_key;
  50         guchar *server_key;
  51         gsize key_length;
  52 } *context_tls_dsk;
  53
  54 /* sip-sec-mech.h API implementation for TLS-DSK */
  55
  56 static sip_uint32
  57 sip_sec_acquire_cred__tls_dsk(SipSecContext context,
  58                               SIPE_UNUSED_PARAMETER const char *domain,
  59                               SIPE_UNUSED_PARAMETER const char *username,
  60                               const char *password)
  61 {
  62         context_tls_dsk ctx = (context_tls_dsk)context;
  63
  64         ctx->state = sipe_tls_start((gpointer) password);
  65         return(ctx->state ? SIP_SEC_E_OK : SIP_SEC_E_INTERNAL_ERROR);
  66 }
  67
  68 static sip_uint32
  69 sip_sec_init_sec_context__tls_dsk(SipSecContext context,
  70                                   SipSecBuffer in_buff,
  71                                   SipSecBuffer *out_buff,
  72                                   SIPE_UNUSED_PARAMETER const char *service_name)
  73 {
  74         context_tls_dsk ctx = (context_tls_dsk) context;
  75         struct sipe_tls_state *state = ctx->state;
  76
  77         state->in_buffer = in_buff.value;
  78         state->in_length = in_buff.length;
  79
  80         if (sipe_tls_next(state)) {
  81                 if ((state->algorithm != SIPE_TLS_DIGEST_ALGORITHM_NONE) &&
  82                     state->client_key && state->server_key) {
  83                         /* Authentication is completed */
  84                         ctx->common.is_ready = TRUE;
  85
  86                         /* copy key pair */
  87                         ctx->algorithm  = state->algorithm;
  88                         ctx->key_length = state->key_length;
  89                         ctx->client_key = g_memdup(state->client_key,
  90                                                    state->key_length);
  91                         ctx->server_key = g_memdup(state->server_key,
  92                                                    state->key_length);
  93
  94                         /* [MS-SIPAE] Section 3.2.2 Timers
  95                          *
  96                          * ... For an SA established using the TLS-DSK
  97                          * authentication protocol, the client MUST
  98                          * retrieve the expiration time of its certificate.
  99                          * The expiration timer value is the lesser of the
 100                          * interval to the certificate expiration and eight
 101                          * hours, ...
 102                          */
 103                         ctx->common.expires = sipe_tls_expires(state);
 104                         if (ctx->common.expires > (8 * 60 * 60))
 105                                 ctx->common.expires = 8 * 60 * 60;
 106
 107                         SIPE_DEBUG_INFO("sip_sec_init_sec_context__tls_dsk: handshake completed, algorithm %d, key length %" G_GSIZE_FORMAT ", expires %d",
 108                                         ctx->algorithm, ctx->key_length, ctx->common.expires);
 109
 110                         sipe_tls_free(state);
 111                         ctx->state = NULL;
 112                 } else {
 113                         out_buff->value  = state->out_buffer;
 114                         out_buff->length = state->out_length;
 115                         /* we take ownership of the buffer */
 116                         state->out_buffer = NULL;
 117                 }
 118         } else {
 119                 sipe_tls_free(state);
 120                 ctx->state = NULL;
 121         }
 122
 123         return((ctx->common.is_ready || ctx->state) ? SIP_SEC_E_OK : SIP_SEC_E_INTERNAL_ERROR);
 124 }
 125
 126 static sip_uint32
 127 sip_sec_make_signature__tls_dsk(SipSecContext context,
 128                                 const char *message,
 129                                 SipSecBuffer *signature)
 130 {
 131         context_tls_dsk ctx = (context_tls_dsk) context;
 132         sip_uint32 result = SIP_SEC_E_INTERNAL_ERROR;
 133
 134         switch (ctx->algorithm) {
 135         case SIPE_TLS_DIGEST_ALGORITHM_MD5:
 136                 signature->length = SIPE_DIGEST_HMAC_MD5_LENGTH;
 137                 signature->value  = g_malloc0(signature->length);
 138                 sipe_digest_hmac_md5(ctx->client_key, ctx->key_length,
 139                                      (guchar *) message, strlen(message),
 140                                      signature->value);
 141                 result = SIP_SEC_E_OK;
 142                 break;
 143
 144         case SIPE_TLS_DIGEST_ALGORITHM_SHA1:
 145                 signature->length = SIPE_DIGEST_HMAC_SHA1_LENGTH;
 146                 signature->value  = g_malloc0(signature->length);
 147                 sipe_digest_hmac_sha1(ctx->client_key, ctx->key_length,
 148                                       (guchar *) message, strlen(message),
 149                                       signature->value);
 150                 result = SIP_SEC_E_OK;
 151                 break;
 152
 153         default:
 154                 /* this should not happen */
 155                 break;
 156         }
 157
 158         return(result);
 159 }
 160
 161 static sip_uint32
 162 sip_sec_verify_signature__tls_dsk(SipSecContext context,
 163                                   const char *message,
 164                                   SipSecBuffer signature)
 165 {
 166         context_tls_dsk ctx = (context_tls_dsk) context;
 167         SipSecBuffer mac    = { 0, NULL };
 168         sip_uint32 result   = SIP_SEC_E_INTERNAL_ERROR;
 169
 170         switch (ctx->algorithm) {
 171         case SIPE_TLS_DIGEST_ALGORITHM_MD5:
 172                 mac.length = SIPE_DIGEST_HMAC_MD5_LENGTH;
 173                 mac.value  = g_malloc0(mac.length);
 174                 sipe_digest_hmac_md5(ctx->server_key, ctx->key_length,
 175                                      (guchar *) message, strlen(message),
 176                                      mac.value);
 177                 break;
 178
 179         case SIPE_TLS_DIGEST_ALGORITHM_SHA1:
 180                 mac.length = SIPE_DIGEST_HMAC_SHA1_LENGTH;
 181                 mac.value  = g_malloc0(mac.length);
 182                 sipe_digest_hmac_sha1(ctx->server_key, ctx->key_length,
 183                                       (guchar *) message, strlen(message),
 184                                       mac.value);
 185                 break;
 186
 187         default:
 188                 /* this should not happen */
 189                 break;
 190         }
 191
 192         if (mac.value) {
 193                 result = memcmp(signature.value, mac.value, mac.length) ?
 194                         SIP_SEC_E_INTERNAL_ERROR : SIP_SEC_E_OK;
 195                 g_free(mac.value);
 196         }
 197
 198         return(result);
 199 }
 200
 201 static void
 202 sip_sec_destroy_sec_context__tls_dsk(SipSecContext context)
 203 {
 204         context_tls_dsk ctx = (context_tls_dsk) context;
 205
 206         sipe_tls_free(ctx->state);
 207         g_free(ctx->client_key);
 208         g_free(ctx->server_key);
 209         g_free(ctx);
 210 }
 211
 212 SipSecContext
 213 sip_sec_create_context__tls_dsk(SIPE_UNUSED_PARAMETER guint type)
 214 {
 215         context_tls_dsk context = g_malloc0(sizeof(struct _context_tls_dsk));
 216         if (!context) return(NULL);
 217
 218         context->common.acquire_cred_func     = sip_sec_acquire_cred__tls_dsk;
 219         context->common.init_context_func     = sip_sec_init_sec_context__tls_dsk;
 220         context->common.destroy_context_func  = sip_sec_destroy_sec_context__tls_dsk;
 221         context->common.make_signature_func   = sip_sec_make_signature__tls_dsk;
 222         context->common.verify_signature_func = sip_sec_verify_signature__tls_dsk;
 223
 224         return((SipSecContext) context);
 225 }
 226
 227 gboolean sip_sec_password__tls_dsk(void)
 228 {
 229         return(TRUE);
 230 }
 231
 232 /*
 233   Local Variables:
 234   mode: c
 235   c-file-style: "bsd"
 236   indent-tabs-mode: t
 237   tab-width: 8
 238   End:
 239 */