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
61static int
62get_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
100static void
101log_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 */
132int 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
272CURLcode 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
363static 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
378void Curl_cleanup_negotiate(struct SessionHandle *data)
379{
380  cleanup(&data->state.negotiate);
381  cleanup(&data->state.proxyneg);
382}
383
384
385#endif
386#endif
387