lib/http_negotiate.c

   1 /***************************************************************************
   2  *                                  _   _ ____  _
   3  *  Project                     ___| | | |  _ \| |
   4  *                             / __| | | | |_) | |
   5  *                            | (__| |_| |  _ <| |___
   6  *                             \___|\___/|_| \_\_____|
   7  *
   8  * Copyright (C) 1998 - 2013, Daniel Stenberg, <daniel@haxx.se>, et al.
   9  *
  10  * This software is licensed as described in the file COPYING, which
  11  * you should have received as part of this distribution. The terms
  12  * are also available at http://curl.haxx.se/docs/copyright.html.
  13  *
  14  * You may opt to use, copy, modify, merge, publish, distribute and/or sell
  15  * copies of the Software, and permit persons to whom the Software is
  16  * furnished to do so, under the terms of the COPYING file.
  17  *
  18  * This software is distributed on an "AS IS" basis, WITHOUT WARRANTY OF ANY
  19  * KIND, either express or implied.
  20  *
  21  ***************************************************************************/
  22
  23 #include "curl_setup.h"
  24
  25 #ifdef HAVE_GSSAPI
  26 #ifdef HAVE_OLD_GSSMIT
  27 #define GSS_C_NT_HOSTBASED_SERVICE gss_nt_service_name
  28 #define NCOMPAT 1
  29 #endif
  30
  31 #ifndef CURL_DISABLE_HTTP
  32
  33 #include "urldata.h"
  34 #include "sendf.h"
  35 #include "curl_gssapi.h"
  36 #include "rawstr.h"
  37 #include "curl_base64.h"
  38 #include "http_negotiate.h"
  39 #include "curl_memory.h"
  40 #include "url.h"
  41
  42 #ifdef HAVE_SPNEGO
  43 #  include <spnegohelp.h>
  44 #  ifdef USE_SSLEAY
  45 #    ifdef USE_OPENSSL
  46 #      include <openssl/objects.h>
  47 #    else
  48 #      include <objects.h>
  49 #    endif
  50 #  else
  51 #    error "Can't compile SPNEGO support without OpenSSL."
  52 #  endif
  53 #endif
  54
  55 #define _MPRINTF_REPLACE /* use our functions only */
  56 #include <curl/mprintf.h>
  57
  58 /* The last #include file should be: */
  59 #include "memdebug.h"
  60
  61 static int
  62 get_gss_name(struct connectdata *conn, bool proxy, gss_name_t *server)
  63 {
  64   struct negotiatedata *neg_ctx = proxy?&conn->data->state.proxyneg:
  65     &conn->data->state.negotiate;
  66   OM_uint32 major_status, minor_status;
  67   gss_buffer_desc token = GSS_C_EMPTY_BUFFER;
  68   char name[2048];
  69   const char* service;
  70
  71   /* GSSAPI implementation by Globus (known as GSI) requires the name to be
  72      of form "<service>/<fqdn>" instead of <service>@<fqdn> (ie. slash instead
  73      of at-sign). Also GSI servers are often identified as 'host' not 'khttp'.
  74      Change following lines if you want to use GSI */
  75
  76   /* IIS uses the <service>@<fqdn> form but uses 'http' as the service name */
  77
  78   if(neg_ctx->gss)
  79     service = "KHTTP";
  80   else
  81     service = "HTTP";
  82
  83   token.length = strlen(service) + 1 + strlen(proxy ? conn->proxy.name :
  84                                               conn->host.name) + 1;
  85   if(token.length + 1 > sizeof(name))
  86     return EMSGSIZE;
  87
  88   snprintf(name, sizeof(name), "%s@%s", service, proxy ? conn->proxy.name :
  89            conn->host.name);
  90
  91   token.value = (void *) name;
  92   major_status = gss_import_name(&minor_status,
  93                                  &token,
  94                                  GSS_C_NT_HOSTBASED_SERVICE,
  95                                  server);
  96
  97   return GSS_ERROR(major_status) ? -1 : 0;
  98 }
  99
 100 static void
 101 log_gss_error(struct connectdata *conn, OM_uint32 error_status,
 102               const char *prefix)
 103 {
 104   OM_uint32 maj_stat, min_stat;
 105   OM_uint32 msg_ctx = 0;
 106   gss_buffer_desc status_string;
 107   char buf[1024];
 108   size_t len;
 109
 110   snprintf(buf, sizeof(buf), "%s", prefix);
 111   len = strlen(buf);
 112   do {
 113     maj_stat = gss_display_status(&min_stat,
 114                                   error_status,
 115                                   GSS_C_MECH_CODE,
 116                                   GSS_C_NO_OID,
 117                                   &msg_ctx,
 118                                   &status_string);
 119       if(sizeof(buf) > len + status_string.length + 1) {
 120         snprintf(buf + len, sizeof(buf) - len,
 121                  ": %s", (char*) status_string.value);
 122       len += status_string.length;
 123     }
 124     gss_release_buffer(&min_stat, &status_string);
 125   } while(!GSS_ERROR(maj_stat) && msg_ctx != 0);
 126
 127   infof(conn->data, "%s\n", buf);
 128 }
 129
 130 /* returning zero (0) means success, everything else is treated as "failure"
 131    with no care exactly what the failure was */
 132 int Curl_input_negotiate(struct connectdata *conn, bool proxy,
 133                          const char *header)
 134 {
 135   struct SessionHandle *data = conn->data;
 136   struct negotiatedata *neg_ctx = proxy?&data->state.proxyneg:
 137     &data->state.negotiate;
 138   OM_uint32 major_status, minor_status, discard_st;
 139   gss_buffer_desc input_token = GSS_C_EMPTY_BUFFER;
 140   gss_buffer_desc output_token = GSS_C_EMPTY_BUFFER;
 141   int ret;
 142   size_t len;
 143   size_t rawlen = 0;
 144   bool gss;
 145   const char* protocol;
 146   CURLcode error;
 147
 148   if(checkprefix("GSS-Negotiate", header)) {
 149     protocol = "GSS-Negotiate";
 150     gss = TRUE;
 151   }
 152   else if(checkprefix("Negotiate", header)) {
 153     protocol = "Negotiate";
 154     gss = FALSE;
 155   }
 156   else
 157     return -1;
 158
 159   if(neg_ctx->context) {
 160     if(neg_ctx->gss != gss) {
 161       return -1;
 162     }
 163   }
 164   else {
 165     neg_ctx->protocol = protocol;
 166     neg_ctx->gss = gss;
 167   }
 168
 169   if(neg_ctx->context && neg_ctx->status == GSS_S_COMPLETE) {
 170     /* We finished successfully our part of authentication, but server
 171      * rejected it (since we're again here). Exit with an error since we
 172      * can't invent anything better */
 173     Curl_cleanup_negotiate(data);
 174     return -1;
 175   }
 176
 177   if(neg_ctx->server_name == NULL &&
 178       (ret = get_gss_name(conn, proxy, &neg_ctx->server_name)))
 179     return ret;
 180
 181   header += strlen(neg_ctx->protocol);
 182   while(*header && ISSPACE(*header))
 183     header++;
 184
 185   len = strlen(header);
 186   if(len > 0) {
 187     error = Curl_base64_decode(header,
 188                                (unsigned char **)&input_token.value, &rawlen);
 189     if(error || rawlen == 0)
 190       return -1;
 191     input_token.length = rawlen;
 192
 193     DEBUGASSERT(input_token.value != NULL);
 194
 195 #ifdef HAVE_SPNEGO /* Handle SPNEGO */
 196     if(checkprefix("Negotiate", header)) {
 197       unsigned char  *spnegoToken       = NULL;
 198       size_t          spnegoTokenLength = 0;
 199       gss_buffer_desc mechToken         = GSS_C_EMPTY_BUFFER;
 200
 201       spnegoToken = malloc(input_token.length);
 202       if(spnegoToken == NULL) {
 203         Curl_safefree(input_token.value);
 204         return CURLE_OUT_OF_MEMORY;
 205       }
 206       memcpy(spnegoToken, input_token.value, input_token.length);
 207       spnegoTokenLength = input_token.length;
 208
 209       if(!parseSpnegoTargetToken(spnegoToken,
 210                                  spnegoTokenLength,
 211                                  NULL,
 212                                  NULL,
 213                                  (unsigned char**)&mechToken.value,
 214                                  &mechToken.length,
 215                                  NULL,
 216                                  NULL)) {
 217         Curl_safefree(spnegoToken);
 218         infof(data, "Parse SPNEGO Target Token failed\n");
 219       }
 220       else if(!mechToken.value || !mechToken.length) {
 221         Curl_safefree(spnegoToken);
 222         if(mechToken.value)
 223           gss_release_buffer(&discard_st, &mechToken);
 224         infof(data, "Parse SPNEGO Target Token succeeded (NULL token)\n");
 225       }
 226       else {
 227         Curl_safefree(spnegoToken);
 228         Curl_safefree(input_token.value);
 229         input_token.value = malloc(mechToken.length);
 230         if(input_token.value == NULL) {
 231           gss_release_buffer(&discard_st, &mechToken);
 232           return CURLE_OUT_OF_MEMORY;
 233         }
 234         memcpy(input_token.value, mechToken.value, mechToken.length);
 235         input_token.length = mechToken.length;
 236         gss_release_buffer(&discard_st, &mechToken);
 237         infof(data, "Parse SPNEGO Target Token succeeded\n");
 238       }
 239     }
 240 #endif
 241   }
 242
 243   major_status = Curl_gss_init_sec_context(data,
 244                                            &minor_status,
 245                                            &neg_ctx->context,
 246                                            neg_ctx->server_name,
 247                                            GSS_C_NO_CHANNEL_BINDINGS,
 248                                            &input_token,
 249                                            &output_token,
 250                                            NULL);
 251   Curl_safefree(input_token.value);
 252
 253   neg_ctx->status = major_status;
 254   if(GSS_ERROR(major_status)) {
 255     if(output_token.value)
 256       gss_release_buffer(&discard_st, &output_token);
 257     log_gss_error(conn, minor_status, "gss_init_sec_context() failed: ");
 258     return -1;
 259   }
 260
 261   if(!output_token.value || !output_token.length) {
 262     if(output_token.value)
 263       gss_release_buffer(&discard_st, &output_token);
 264     return -1;
 265   }
 266
 267   neg_ctx->output_token = output_token;
 268   return 0;
 269 }
 270
 271
 272 CURLcode Curl_output_negotiate(struct connectdata *conn, bool proxy)
 273 {
 274   struct negotiatedata *neg_ctx = proxy?&conn->data->state.proxyneg:
 275     &conn->data->state.negotiate;
 276   char *encoded = NULL;
 277   size_t len = 0;
 278   char *userp;
 279   CURLcode error;
 280   OM_uint32 discard_st;
 281
 282 #ifdef HAVE_SPNEGO /* Handle SPNEGO */
 283   if(checkprefix("Negotiate", neg_ctx->protocol)) {
 284     ASN1_OBJECT    *object              = NULL;
 285     unsigned char  *responseToken       = NULL;
 286     size_t          responseTokenLength = 0;
 287     gss_buffer_desc spnegoToken         = GSS_C_EMPTY_BUFFER;
 288
 289     responseToken = malloc(neg_ctx->output_token.length);
 290     if(responseToken == NULL)
 291       return CURLE_OUT_OF_MEMORY;
 292     memcpy(responseToken, neg_ctx->output_token.value,
 293            neg_ctx->output_token.length);
 294     responseTokenLength = neg_ctx->output_token.length;
 295
 296     object = OBJ_txt2obj("1.2.840.113554.1.2.2", 1);
 297     if(!object) {
 298       Curl_safefree(responseToken);
 299       return CURLE_OUT_OF_MEMORY;
 300     }
 301
 302     if(!makeSpnegoInitialToken(object,
 303                                responseToken,
 304                                responseTokenLength,
 305                                (unsigned char**)&spnegoToken.value,
 306                                &spnegoToken.length)) {
 307       Curl_safefree(responseToken);
 308       ASN1_OBJECT_free(object);
 309       infof(conn->data, "Make SPNEGO Initial Token failed\n");
 310     }
 311     else if(!spnegoToken.value || !spnegoToken.length) {
 312       Curl_safefree(responseToken);
 313       ASN1_OBJECT_free(object);
 314       if(spnegoToken.value)
 315         gss_release_buffer(&discard_st, &spnegoToken);
 316       infof(conn->data, "Make SPNEGO Initial Token succeeded (NULL token)\n");
 317     }
 318     else {
 319       Curl_safefree(responseToken);
 320       ASN1_OBJECT_free(object);
 321       gss_release_buffer(&discard_st, &neg_ctx->output_token);
 322       neg_ctx->output_token.value = spnegoToken.value;
 323       neg_ctx->output_token.length = spnegoToken.length;
 324       infof(conn->data, "Make SPNEGO Initial Token succeeded\n");
 325     }
 326   }
 327 #endif
 328   error = Curl_base64_encode(conn->data,
 329                              neg_ctx->output_token.value,
 330                              neg_ctx->output_token.length,
 331                              &encoded, &len);
 332   if(error) {
 333     gss_release_buffer(&discard_st, &neg_ctx->output_token);
 334     neg_ctx->output_token.value = NULL;
 335     neg_ctx->output_token.length = 0;
 336     return error;
 337   }
 338
 339   if(!encoded || !len) {
 340     gss_release_buffer(&discard_st, &neg_ctx->output_token);
 341     neg_ctx->output_token.value = NULL;
 342     neg_ctx->output_token.length = 0;
 343     return CURLE_REMOTE_ACCESS_DENIED;
 344   }
 345
 346   userp = aprintf("%sAuthorization: %s %s\r\n", proxy ? "Proxy-" : "",
 347                   neg_ctx->protocol, encoded);
 348   if(proxy) {
 349     Curl_safefree(conn->allocptr.proxyuserpwd);
 350     conn->allocptr.proxyuserpwd = userp;
 351   }
 352   else {
 353     Curl_safefree(conn->allocptr.userpwd);
 354     conn->allocptr.userpwd = userp;
 355   }
 356
 357   Curl_safefree(encoded);
 358   Curl_cleanup_negotiate(conn->data);
 359
 360   return (userp == NULL) ? CURLE_OUT_OF_MEMORY : CURLE_OK;
 361 }
 362
 363 static void cleanup(struct negotiatedata *neg_ctx)
 364 {
 365   OM_uint32 minor_status;
 366   if(neg_ctx->context != GSS_C_NO_CONTEXT)
 367     gss_delete_sec_context(&minor_status, &neg_ctx->context, GSS_C_NO_BUFFER);
 368
 369   if(neg_ctx->output_token.value)
 370     gss_release_buffer(&minor_status, &neg_ctx->output_token);
 371
 372   if(neg_ctx->server_name != GSS_C_NO_NAME)
 373     gss_release_name(&minor_status, &neg_ctx->server_name);
 374
 375   memset(neg_ctx, 0, sizeof(*neg_ctx));
 376 }
 377
 378 void Curl_cleanup_negotiate(struct SessionHandle *data)
 379 {
 380   cleanup(&data->state.negotiate);
 381   cleanup(&data->state.proxyneg);
 382 }
 383
 384
 385 #endif
 386 #endif