1 /***************************************************************************
3 * Project ___| | | | _ \| |
5 * | (__| |_| | _ <| |___
6 * \___|\___/|_| \_\_____|
8 * Copyright (C) 2009, 2011, Markus Moeller, <markus_moeller@compuserve.com>
9 * Copyright (C) 2012 - 2015, Daniel Stenberg, <daniel@haxx.se>, et al.
11 * This software is licensed as described in the file COPYING, which
12 * you should have received as part of this distribution. The terms
13 * are also available at http://curl.haxx.se/docs/copyright.html.
15 * You may opt to use, copy, modify, merge, publish, distribute and/or sell
16 * copies of the Software, and permit persons to whom the Software is
17 * furnished to do so, under the terms of the COPYING file.
19 * This software is distributed on an "AS IS" basis, WITHOUT WARRANTY OF ANY
20 * KIND, either express or implied.
22 ***************************************************************************/
24 #include "curl_setup.h"
26 #if defined(HAVE_GSSAPI) && !defined(CURL_DISABLE_PROXY)
28 #include "curl_gssapi.h"
35 #include "curl_printf.h"
36 #include "curl_memory.h"
37 /* The last #include file should be: */
40 static gss_ctx_id_t gss_context = GSS_C_NO_CONTEXT;
43 * Helper GSS-API error functions.
45 static int check_gss_err(struct SessionHandle *data,
46 OM_uint32 major_status,
47 OM_uint32 minor_status,
50 if(GSS_ERROR(major_status)) {
51 OM_uint32 maj_stat, min_stat;
52 OM_uint32 msg_ctx = 0;
53 gss_buffer_desc status_string;
60 /* convert major status code (GSS-API error) to text */
61 maj_stat = gss_display_status(&min_stat, major_status,
64 &msg_ctx, &status_string);
65 if(maj_stat == GSS_S_COMPLETE) {
66 if(sizeof(buf) > len + status_string.length + 1) {
67 strcpy(buf+len, (char*) status_string.value);
68 len += status_string.length;
70 gss_release_buffer(&min_stat, &status_string);
73 gss_release_buffer(&min_stat, &status_string);
75 if(sizeof(buf) > len + 3) {
76 strcpy(buf+len, ".\n");
81 /* convert minor status code (underlying routine error) to text */
82 maj_stat = gss_display_status(&min_stat, minor_status,
85 &msg_ctx, &status_string);
86 if(maj_stat == GSS_S_COMPLETE) {
87 if(sizeof(buf) > len + status_string.length)
88 strcpy(buf+len, (char*) status_string.value);
89 gss_release_buffer(&min_stat, &status_string);
92 gss_release_buffer(&min_stat, &status_string);
94 failf(data, "GSS-API error: %s failed:\n%s", function, buf);
101 CURLcode Curl_SOCKS5_gssapi_negotiate(int sockindex,
102 struct connectdata *conn)
104 struct SessionHandle *data = conn->data;
105 curl_socket_t sock = conn->sock[sockindex];
110 OM_uint32 gss_major_status, gss_minor_status, gss_status;
111 OM_uint32 gss_ret_flags;
112 int gss_conf_state, gss_enc;
113 gss_buffer_desc service = GSS_C_EMPTY_BUFFER;
114 gss_buffer_desc gss_send_token = GSS_C_EMPTY_BUFFER;
115 gss_buffer_desc gss_recv_token = GSS_C_EMPTY_BUFFER;
116 gss_buffer_desc gss_w_token = GSS_C_EMPTY_BUFFER;
117 gss_buffer_desc* gss_token = GSS_C_NO_BUFFER;
118 gss_name_t server = GSS_C_NO_NAME;
119 gss_name_t gss_client_name = GSS_C_NO_NAME;
120 unsigned short us_length;
122 unsigned char socksreq[4]; /* room for GSS-API exchange header only */
123 char *serviceptr = data->set.str[STRING_SOCKS5_GSSAPI_SERVICE];
125 /* GSS-API request looks like
126 * +----+------+-----+----------------+
127 * |VER | MTYP | LEN | TOKEN |
128 * +----+------+----------------------+
129 * | 1 | 1 | 2 | up to 2^16 - 1 |
130 * +----+------+-----+----------------+
133 /* prepare service name */
134 if(strchr(serviceptr, '/')) {
135 service.value = malloc(strlen(serviceptr));
137 return CURLE_OUT_OF_MEMORY;
138 service.length = strlen(serviceptr);
139 memcpy(service.value, serviceptr, service.length);
141 gss_major_status = gss_import_name(&gss_minor_status, &service,
142 (gss_OID) GSS_C_NULL_OID, &server);
145 service.value = malloc(strlen(serviceptr) +strlen(conn->proxy.name)+2);
147 return CURLE_OUT_OF_MEMORY;
148 service.length = strlen(serviceptr) +strlen(conn->proxy.name)+1;
149 snprintf(service.value, service.length+1, "%s@%s",
150 serviceptr, conn->proxy.name);
152 gss_major_status = gss_import_name(&gss_minor_status, &service,
153 GSS_C_NT_HOSTBASED_SERVICE, &server);
156 gss_release_buffer(&gss_status, &service); /* clear allocated memory */
158 if(check_gss_err(data, gss_major_status,
159 gss_minor_status, "gss_import_name()")) {
160 failf(data, "Failed to create service name.");
161 gss_release_name(&gss_status, &server);
162 return CURLE_COULDNT_CONNECT;
165 /* As long as we need to keep sending some context info, and there's no */
166 /* errors, keep sending it... */
168 gss_major_status = Curl_gss_init_sec_context(data,
179 if(gss_token != GSS_C_NO_BUFFER)
180 gss_release_buffer(&gss_status, &gss_recv_token);
181 if(check_gss_err(data, gss_major_status,
182 gss_minor_status, "gss_init_sec_context")) {
183 gss_release_name(&gss_status, &server);
184 gss_release_buffer(&gss_status, &gss_recv_token);
185 gss_release_buffer(&gss_status, &gss_send_token);
186 gss_delete_sec_context(&gss_status, &gss_context, NULL);
187 failf(data, "Failed to initial GSS-API token.");
188 return CURLE_COULDNT_CONNECT;
191 if(gss_send_token.length != 0) {
192 socksreq[0] = 1; /* GSS-API subnegotiation version */
193 socksreq[1] = 1; /* authentication message type */
194 us_length = htons((short)gss_send_token.length);
195 memcpy(socksreq+2, &us_length, sizeof(short));
197 code = Curl_write_plain(conn, sock, (char *)socksreq, 4, &written);
198 if(code || (4 != written)) {
199 failf(data, "Failed to send GSS-API authentication request.");
200 gss_release_name(&gss_status, &server);
201 gss_release_buffer(&gss_status, &gss_recv_token);
202 gss_release_buffer(&gss_status, &gss_send_token);
203 gss_delete_sec_context(&gss_status, &gss_context, NULL);
204 return CURLE_COULDNT_CONNECT;
207 code = Curl_write_plain(conn, sock, (char *)gss_send_token.value,
208 gss_send_token.length, &written);
210 if(code || ((ssize_t)gss_send_token.length != written)) {
211 failf(data, "Failed to send GSS-API authentication token.");
212 gss_release_name(&gss_status, &server);
213 gss_release_buffer(&gss_status, &gss_recv_token);
214 gss_release_buffer(&gss_status, &gss_send_token);
215 gss_delete_sec_context(&gss_status, &gss_context, NULL);
216 return CURLE_COULDNT_CONNECT;
221 gss_release_buffer(&gss_status, &gss_send_token);
222 gss_release_buffer(&gss_status, &gss_recv_token);
223 if(gss_major_status != GSS_S_CONTINUE_NEEDED) break;
225 /* analyse response */
227 /* GSS-API response looks like
228 * +----+------+-----+----------------+
229 * |VER | MTYP | LEN | TOKEN |
230 * +----+------+----------------------+
231 * | 1 | 1 | 2 | up to 2^16 - 1 |
232 * +----+------+-----+----------------+
235 result=Curl_blockread_all(conn, sock, (char *)socksreq, 4, &actualread);
236 if(result || (actualread != 4)) {
237 failf(data, "Failed to receive GSS-API authentication response.");
238 gss_release_name(&gss_status, &server);
239 gss_delete_sec_context(&gss_status, &gss_context, NULL);
240 return CURLE_COULDNT_CONNECT;
243 /* ignore the first (VER) byte */
244 if(socksreq[1] == 255) { /* status / message type */
245 failf(data, "User was rejected by the SOCKS5 server (%d %d).",
246 socksreq[0], socksreq[1]);
247 gss_release_name(&gss_status, &server);
248 gss_delete_sec_context(&gss_status, &gss_context, NULL);
249 return CURLE_COULDNT_CONNECT;
252 if(socksreq[1] != 1) { /* status / messgae type */
253 failf(data, "Invalid GSS-API authentication response type (%d %d).",
254 socksreq[0], socksreq[1]);
255 gss_release_name(&gss_status, &server);
256 gss_delete_sec_context(&gss_status, &gss_context, NULL);
257 return CURLE_COULDNT_CONNECT;
260 memcpy(&us_length, socksreq+2, sizeof(short));
261 us_length = ntohs(us_length);
263 gss_recv_token.length=us_length;
264 gss_recv_token.value=malloc(us_length);
265 if(!gss_recv_token.value) {
267 "Could not allocate memory for GSS-API authentication "
269 gss_release_name(&gss_status, &server);
270 gss_delete_sec_context(&gss_status, &gss_context, NULL);
271 return CURLE_OUT_OF_MEMORY;
274 result=Curl_blockread_all(conn, sock, (char *)gss_recv_token.value,
275 gss_recv_token.length, &actualread);
277 if(result || (actualread != us_length)) {
278 failf(data, "Failed to receive GSS-API authentication token.");
279 gss_release_name(&gss_status, &server);
280 gss_release_buffer(&gss_status, &gss_recv_token);
281 gss_delete_sec_context(&gss_status, &gss_context, NULL);
282 return CURLE_COULDNT_CONNECT;
285 gss_token = &gss_recv_token;
288 gss_release_name(&gss_status, &server);
290 /* Everything is good so far, user was authenticated! */
291 gss_major_status = gss_inquire_context (&gss_minor_status, gss_context,
292 &gss_client_name, NULL, NULL, NULL,
294 if(check_gss_err(data, gss_major_status,
295 gss_minor_status, "gss_inquire_context")) {
296 gss_delete_sec_context(&gss_status, &gss_context, NULL);
297 gss_release_name(&gss_status, &gss_client_name);
298 failf(data, "Failed to determine user name.");
299 return CURLE_COULDNT_CONNECT;
301 gss_major_status = gss_display_name(&gss_minor_status, gss_client_name,
302 &gss_send_token, NULL);
303 if(check_gss_err(data, gss_major_status,
304 gss_minor_status, "gss_display_name")) {
305 gss_delete_sec_context(&gss_status, &gss_context, NULL);
306 gss_release_name(&gss_status, &gss_client_name);
307 gss_release_buffer(&gss_status, &gss_send_token);
308 failf(data, "Failed to determine user name.");
309 return CURLE_COULDNT_CONNECT;
311 user=malloc(gss_send_token.length+1);
313 gss_delete_sec_context(&gss_status, &gss_context, NULL);
314 gss_release_name(&gss_status, &gss_client_name);
315 gss_release_buffer(&gss_status, &gss_send_token);
316 return CURLE_OUT_OF_MEMORY;
319 memcpy(user, gss_send_token.value, gss_send_token.length);
320 user[gss_send_token.length] = '\0';
321 gss_release_name(&gss_status, &gss_client_name);
322 gss_release_buffer(&gss_status, &gss_send_token);
323 infof(data, "SOCKS5 server authencticated user %s with GSS-API.\n",user);
328 socksreq[0] = 1; /* GSS-API subnegotiation version */
329 socksreq[1] = 2; /* encryption message type */
331 gss_enc = 0; /* no data protection */
332 /* do confidentiality protection if supported */
333 if(gss_ret_flags & GSS_C_CONF_FLAG)
335 /* else do integrity protection */
336 else if(gss_ret_flags & GSS_C_INTEG_FLAG)
339 infof(data, "SOCKS5 server supports GSS-API %s data protection.\n",
340 (gss_enc==0)?"no":((gss_enc==1)?"integrity":"confidentiality"));
341 /* force for the moment to no data protection */
344 * Sending the encryption type in clear seems wrong. It should be
345 * protected with gss_seal()/gss_wrap(). See RFC1961 extract below
346 * The NEC reference implementations on which this is based is
349 * +------+------+------+.......................+
350 * + ver | mtyp | len | token |
351 * +------+------+------+.......................+
352 * + 0x01 | 0x02 | 0x02 | up to 2^16 - 1 octets |
353 * +------+------+------+.......................+
357 * - "ver" is the protocol version number, here 1 to represent the
358 * first version of the SOCKS/GSS-API protocol
360 * - "mtyp" is the message type, here 2 to represent a protection
361 * -level negotiation message
363 * - "len" is the length of the "token" field in octets
365 * - "token" is the GSS-API encapsulated protection level
367 * The token is produced by encapsulating an octet containing the
368 * required protection level using gss_seal()/gss_wrap() with conf_req
369 * set to FALSE. The token is verified using gss_unseal()/
373 if(data->set.socks5_gssapi_nec) {
374 us_length = htons((short)1);
375 memcpy(socksreq+2, &us_length, sizeof(short));
378 gss_send_token.length = 1;
379 gss_send_token.value = malloc(1);
380 if(!gss_send_token.value) {
381 gss_delete_sec_context(&gss_status, &gss_context, NULL);
382 return CURLE_OUT_OF_MEMORY;
384 memcpy(gss_send_token.value, &gss_enc, 1);
386 gss_major_status = gss_wrap(&gss_minor_status, gss_context, 0,
387 GSS_C_QOP_DEFAULT, &gss_send_token,
388 &gss_conf_state, &gss_w_token);
390 if(check_gss_err(data, gss_major_status, gss_minor_status, "gss_wrap")) {
391 gss_release_buffer(&gss_status, &gss_send_token);
392 gss_release_buffer(&gss_status, &gss_w_token);
393 gss_delete_sec_context(&gss_status, &gss_context, NULL);
394 failf(data, "Failed to wrap GSS-API encryption value into token.");
395 return CURLE_COULDNT_CONNECT;
397 gss_release_buffer(&gss_status, &gss_send_token);
399 us_length = htons((short)gss_w_token.length);
400 memcpy(socksreq+2, &us_length, sizeof(short));
403 code = Curl_write_plain(conn, sock, (char *)socksreq, 4, &written);
404 if(code || (4 != written)) {
405 failf(data, "Failed to send GSS-API encryption request.");
406 gss_release_buffer(&gss_status, &gss_w_token);
407 gss_delete_sec_context(&gss_status, &gss_context, NULL);
408 return CURLE_COULDNT_CONNECT;
411 if(data->set.socks5_gssapi_nec) {
412 memcpy(socksreq, &gss_enc, 1);
413 code = Curl_write_plain(conn, sock, socksreq, 1, &written);
414 if(code || ( 1 != written)) {
415 failf(data, "Failed to send GSS-API encryption type.");
416 gss_delete_sec_context(&gss_status, &gss_context, NULL);
417 return CURLE_COULDNT_CONNECT;
421 code = Curl_write_plain(conn, sock, (char *)gss_w_token.value,
422 gss_w_token.length, &written);
423 if(code || ((ssize_t)gss_w_token.length != written)) {
424 failf(data, "Failed to send GSS-API encryption type.");
425 gss_release_buffer(&gss_status, &gss_w_token);
426 gss_delete_sec_context(&gss_status, &gss_context, NULL);
427 return CURLE_COULDNT_CONNECT;
429 gss_release_buffer(&gss_status, &gss_w_token);
432 result=Curl_blockread_all(conn, sock, (char *)socksreq, 4, &actualread);
433 if(result || (actualread != 4)) {
434 failf(data, "Failed to receive GSS-API encryption response.");
435 gss_delete_sec_context(&gss_status, &gss_context, NULL);
436 return CURLE_COULDNT_CONNECT;
439 /* ignore the first (VER) byte */
440 if(socksreq[1] == 255) { /* status / message type */
441 failf(data, "User was rejected by the SOCKS5 server (%d %d).",
442 socksreq[0], socksreq[1]);
443 gss_delete_sec_context(&gss_status, &gss_context, NULL);
444 return CURLE_COULDNT_CONNECT;
447 if(socksreq[1] != 2) { /* status / messgae type */
448 failf(data, "Invalid GSS-API encryption response type (%d %d).",
449 socksreq[0], socksreq[1]);
450 gss_delete_sec_context(&gss_status, &gss_context, NULL);
451 return CURLE_COULDNT_CONNECT;
454 memcpy(&us_length, socksreq+2, sizeof(short));
455 us_length = ntohs(us_length);
457 gss_recv_token.length= us_length;
458 gss_recv_token.value=malloc(gss_recv_token.length);
459 if(!gss_recv_token.value) {
460 gss_delete_sec_context(&gss_status, &gss_context, NULL);
461 return CURLE_OUT_OF_MEMORY;
463 result=Curl_blockread_all(conn, sock, (char *)gss_recv_token.value,
464 gss_recv_token.length, &actualread);
466 if(result || (actualread != us_length)) {
467 failf(data, "Failed to receive GSS-API encryptrion type.");
468 gss_release_buffer(&gss_status, &gss_recv_token);
469 gss_delete_sec_context(&gss_status, &gss_context, NULL);
470 return CURLE_COULDNT_CONNECT;
473 if(!data->set.socks5_gssapi_nec) {
474 gss_major_status = gss_unwrap(&gss_minor_status, gss_context,
475 &gss_recv_token, &gss_w_token,
476 0, GSS_C_QOP_DEFAULT);
478 if(check_gss_err(data, gss_major_status, gss_minor_status, "gss_unwrap")) {
479 gss_release_buffer(&gss_status, &gss_recv_token);
480 gss_release_buffer(&gss_status, &gss_w_token);
481 gss_delete_sec_context(&gss_status, &gss_context, NULL);
482 failf(data, "Failed to unwrap GSS-API encryption value into token.");
483 return CURLE_COULDNT_CONNECT;
485 gss_release_buffer(&gss_status, &gss_recv_token);
487 if(gss_w_token.length != 1) {
488 failf(data, "Invalid GSS-API encryption response length (%d).",
490 gss_release_buffer(&gss_status, &gss_w_token);
491 gss_delete_sec_context(&gss_status, &gss_context, NULL);
492 return CURLE_COULDNT_CONNECT;
495 memcpy(socksreq, gss_w_token.value, gss_w_token.length);
496 gss_release_buffer(&gss_status, &gss_w_token);
499 if(gss_recv_token.length != 1) {
500 failf(data, "Invalid GSS-API encryption response length (%d).",
501 gss_recv_token.length);
502 gss_release_buffer(&gss_status, &gss_recv_token);
503 gss_delete_sec_context(&gss_status, &gss_context, NULL);
504 return CURLE_COULDNT_CONNECT;
507 memcpy(socksreq, gss_recv_token.value, gss_recv_token.length);
508 gss_release_buffer(&gss_status, &gss_recv_token);
511 infof(data, "SOCKS5 access with%s protection granted.\n",
512 (socksreq[0]==0)?"out GSS-API data":
513 ((socksreq[0]==1)?" GSS-API integrity":" GSS-API confidentiality"));
515 conn->socks5_gssapi_enctype = socksreq[0];
517 gss_delete_sec_context(&gss_status, &gss_context, NULL);
522 #endif /* HAVE_GSSAPI && !CURL_DISABLE_PROXY */