socks_gssapi.c@ 104085

Last change on this file since 104085 was 104083, checked in by vboxsync, 11 months ago
curl-8.7.1: Applied and adjusted our curl changes to 8.4.0. bugref:10639
Property svn:eol-style set to `native`
File size: 19.8 KB

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1	/***************************************************************************
2	* _ _ ____ _
3	* Project ___\| \| \| \| _ \\| \|
4	* / __\| \| \| \| \|_) \| \|
5	* \| (__\| \|_\| \| _ <\| \|___
6	* \___\|\___/\|_\| \_\_____\|
7	*
8	* Copyright (C) Daniel Stenberg, <[email protected]>, et al.
9	* Copyright (C) Markus Moeller, <[email protected]>
10	*
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 https://curl.se/docs/copyright.html.
14	*
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.
18	*
19	* This software is distributed on an "AS IS" basis, WITHOUT WARRANTY OF ANY
20	* KIND, either express or implied.
21	*
22	* SPDX-License-Identifier: curl
23	*
24	***************************************************************************/
25
26	#include "curl_setup.h"
27
28	#if defined(HAVE_GSSAPI) && !defined(CURL_DISABLE_PROXY)
29
30	#include "curl_gssapi.h"
31	#include "urldata.h"
32	#include "sendf.h"
33	#include "cfilters.h"
34	#include "connect.h"
35	#include "timeval.h"
36	#include "socks.h"
37	#include "warnless.h"
38	#include "strdup.h"
39
40	/* The last 3 #include files should be in this order */
41	#include "curl_printf.h"
42	#include "curl_memory.h"
43	#include "memdebug.h"
44
45	static gss_ctx_id_t gss_context = GSS_C_NO_CONTEXT;
46
47	/*
48	* Helper GSS-API error functions.
49	*/
50	static int check_gss_err(struct Curl_easy *data,
51	OM_uint32 major_status,
52	OM_uint32 minor_status,
53	const char *function)
54	{
55	if(GSS_ERROR(major_status)) {
56	OM_uint32 maj_stat, min_stat;
57	OM_uint32 msg_ctx = 0;
58	gss_buffer_desc status_string = GSS_C_EMPTY_BUFFER;
59	char buf[1024];
60	size_t len;
61
62	len = 0;
63	msg_ctx = 0;
64	while(!msg_ctx) {
65	/* convert major status code (GSS-API error) to text */
66	maj_stat = gss_display_status(&min_stat, major_status,
67	GSS_C_GSS_CODE,
68	GSS_C_NULL_OID,
69	&msg_ctx, &status_string);
70	if(maj_stat == GSS_S_COMPLETE) {
71	if(sizeof(buf) > len + status_string.length + 1) {
72	strcpy(buf + len, (char *) status_string.value);
73	len += status_string.length;
74	}
75	gss_release_buffer(&min_stat, &status_string);
76	break;
77	}
78	gss_release_buffer(&min_stat, &status_string);
79	}
80	if(sizeof(buf) > len + 3) {
81	strcpy(buf + len, ".\n");
82	len += 2;
83	}
84	msg_ctx = 0;
85	while(!msg_ctx) {
86	/* convert minor status code (underlying routine error) to text */
87	maj_stat = gss_display_status(&min_stat, minor_status,
88	GSS_C_MECH_CODE,
89	GSS_C_NULL_OID,
90	&msg_ctx, &status_string);
91	if(maj_stat == GSS_S_COMPLETE) {
92	if(sizeof(buf) > len + status_string.length)
93	strcpy(buf + len, (char *) status_string.value);
94	gss_release_buffer(&min_stat, &status_string);
95	break;
96	}
97	gss_release_buffer(&min_stat, &status_string);
98	}
99	failf(data, "GSS-API error: %s failed: %s", function, buf);
100	return 1;
101	}
102
103	return 0;
104	}
105
106	CURLcode Curl_SOCKS5_gssapi_negotiate(struct Curl_cfilter *cf,
107	struct Curl_easy *data)
108	{
109	struct connectdata *conn = cf->conn;
110	curl_socket_t sock = conn->sock[cf->sockindex];
111	CURLcode code;
112	ssize_t actualread;
113	ssize_t nwritten;
114	int result;
115	OM_uint32 gss_major_status, gss_minor_status, gss_status;
116	OM_uint32 gss_ret_flags;
117	int gss_conf_state, gss_enc;
118	gss_buffer_desc service = GSS_C_EMPTY_BUFFER;
119	gss_buffer_desc gss_send_token = GSS_C_EMPTY_BUFFER;
120	gss_buffer_desc gss_recv_token = GSS_C_EMPTY_BUFFER;
121	gss_buffer_desc gss_w_token = GSS_C_EMPTY_BUFFER;
122	gss_buffer_desc *gss_token = GSS_C_NO_BUFFER;
123	gss_name_t server = GSS_C_NO_NAME;
124	gss_name_t gss_client_name = GSS_C_NO_NAME;
125	unsigned short us_length;
126	char *user = NULL;
127	unsigned char socksreq[4]; /* room for GSS-API exchange header only */
128	const char *serviceptr = data->set.str[STRING_PROXY_SERVICE_NAME] ?
129	data->set.str[STRING_PROXY_SERVICE_NAME] : "rcmd";
130	const size_t serviceptr_length = strlen(serviceptr);
131
132	/* GSS-API request looks like
133	* +----+------+-----+----------------+
134	* \|VER \| MTYP \| LEN \| TOKEN \|
135	* +----+------+----------------------+
136	* \| 1 \| 1 \| 2 \| up to 2^16 - 1 \|
137	* +----+------+-----+----------------+
138	*/
139
140	/* prepare service name */
141	if(strchr(serviceptr, '/')) {
142	service.length = serviceptr_length;
143	service.value = Curl_memdup(serviceptr, service.length);
144	if(!service.value)
145	return CURLE_OUT_OF_MEMORY;
146
147	gss_major_status = gss_import_name(&gss_minor_status, &service,
148	(gss_OID) GSS_C_NULL_OID, &server);
149	}
150	else {
151	service.value = malloc(serviceptr_length +
152	strlen(conn->socks_proxy.host.name) + 2);
153	if(!service.value)
154	return CURLE_OUT_OF_MEMORY;
155	service.length = serviceptr_length +
156	strlen(conn->socks_proxy.host.name) + 1;
157	msnprintf(service.value, service.length + 1, "%s@%s",
158	serviceptr, conn->socks_proxy.host.name);
159
160	gss_major_status = gss_import_name(&gss_minor_status, &service,
161	GSS_C_NT_HOSTBASED_SERVICE, &server);
162	}
163
164	gss_release_buffer(&gss_status, &service); /* clear allocated memory */
165
166	if(check_gss_err(data, gss_major_status,
167	gss_minor_status, "gss_import_name()")) {
168	failf(data, "Failed to create service name.");
169	gss_release_name(&gss_status, &server);
170	return CURLE_COULDNT_CONNECT;
171	}
172
173	(void)curlx_nonblock(sock, FALSE);
174
175	/* As long as we need to keep sending some context info, and there's no */
176	/* errors, keep sending it... */
177	for(;;) {
178	gss_major_status = Curl_gss_init_sec_context(data,
179	&gss_minor_status,
180	&gss_context,
181	server,
182	&Curl_krb5_mech_oid,
183	NULL,
184	gss_token,
185	&gss_send_token,
186	TRUE,
187	&gss_ret_flags);
188
189	if(gss_token != GSS_C_NO_BUFFER)
190	gss_release_buffer(&gss_status, &gss_recv_token);
191	if(check_gss_err(data, gss_major_status,
192	gss_minor_status, "gss_init_sec_context")) {
193	gss_release_name(&gss_status, &server);
194	gss_release_buffer(&gss_status, &gss_recv_token);
195	gss_release_buffer(&gss_status, &gss_send_token);
196	gss_delete_sec_context(&gss_status, &gss_context, NULL);
197	failf(data, "Failed to initial GSS-API token.");
198	return CURLE_COULDNT_CONNECT;
199	}
200
201	if(gss_send_token.length) {
202	socksreq[0] = 1; /* GSS-API subnegotiation version */
203	socksreq[1] = 1; /* authentication message type */
204	us_length = htons((short)gss_send_token.length);
205	memcpy(socksreq + 2, &us_length, sizeof(short));
206
207	nwritten = Curl_conn_cf_send(cf->next, data, (char *)socksreq, 4, &code);
208	if(code \|\| (4 != nwritten)) {
209	failf(data, "Failed to send GSS-API authentication request.");
210	gss_release_name(&gss_status, &server);
211	gss_release_buffer(&gss_status, &gss_recv_token);
212	gss_release_buffer(&gss_status, &gss_send_token);
213	gss_delete_sec_context(&gss_status, &gss_context, NULL);
214	return CURLE_COULDNT_CONNECT;
215	}
216
217	nwritten = Curl_conn_cf_send(cf->next, data,
218	(char *)gss_send_token.value,
219	gss_send_token.length, &code);
220	if(code \|\| ((ssize_t)gss_send_token.length != nwritten)) {
221	failf(data, "Failed to send GSS-API authentication token.");
222	gss_release_name(&gss_status, &server);
223	gss_release_buffer(&gss_status, &gss_recv_token);
224	gss_release_buffer(&gss_status, &gss_send_token);
225	gss_delete_sec_context(&gss_status, &gss_context, NULL);
226	return CURLE_COULDNT_CONNECT;
227	}
228
229	}
230
231	gss_release_buffer(&gss_status, &gss_send_token);
232	gss_release_buffer(&gss_status, &gss_recv_token);
233	if(gss_major_status != GSS_S_CONTINUE_NEEDED)
234	break;
235
236	/* analyse response */
237
238	/* GSS-API response looks like
239	* +----+------+-----+----------------+
240	* \|VER \| MTYP \| LEN \| TOKEN \|
241	* +----+------+----------------------+
242	* \| 1 \| 1 \| 2 \| up to 2^16 - 1 \|
243	* +----+------+-----+----------------+
244	*/
245
246	result = Curl_blockread_all(cf, data, (char *)socksreq, 4, &actualread);
247	if(result \|\| (actualread != 4)) {
248	failf(data, "Failed to receive GSS-API authentication response.");
249	gss_release_name(&gss_status, &server);
250	gss_delete_sec_context(&gss_status, &gss_context, NULL);
251	return CURLE_COULDNT_CONNECT;
252	}
253
254	/* ignore the first (VER) byte */
255	if(socksreq[1] == 255) { /* status / message type */
256	failf(data, "User was rejected by the SOCKS5 server (%d %d).",
257	socksreq[0], socksreq[1]);
258	gss_release_name(&gss_status, &server);
259	gss_delete_sec_context(&gss_status, &gss_context, NULL);
260	return CURLE_COULDNT_CONNECT;
261	}
262
263	if(socksreq[1] != 1) { /* status / message type */
264	failf(data, "Invalid GSS-API authentication response type (%d %d).",
265	socksreq[0], socksreq[1]);
266	gss_release_name(&gss_status, &server);
267	gss_delete_sec_context(&gss_status, &gss_context, NULL);
268	return CURLE_COULDNT_CONNECT;
269	}
270
271	memcpy(&us_length, socksreq + 2, sizeof(short));
272	us_length = ntohs(us_length);
273
274	gss_recv_token.length = us_length;
275	gss_recv_token.value = malloc(us_length);
276	if(!gss_recv_token.value) {
277	failf(data,
278	"Could not allocate memory for GSS-API authentication "
279	"response token.");
280	gss_release_name(&gss_status, &server);
281	gss_delete_sec_context(&gss_status, &gss_context, NULL);
282	return CURLE_OUT_OF_MEMORY;
283	}
284
285	result = Curl_blockread_all(cf, data, (char *)gss_recv_token.value,
286	gss_recv_token.length, &actualread);
287
288	if(result \|\| (actualread != us_length)) {
289	failf(data, "Failed to receive GSS-API authentication token.");
290	gss_release_name(&gss_status, &server);
291	gss_release_buffer(&gss_status, &gss_recv_token);
292	gss_delete_sec_context(&gss_status, &gss_context, NULL);
293	return CURLE_COULDNT_CONNECT;
294	}
295
296	gss_token = &gss_recv_token;
297	}
298
299	gss_release_name(&gss_status, &server);
300
301	/* Everything is good so far, user was authenticated! */
302	gss_major_status = gss_inquire_context(&gss_minor_status, gss_context,
303	&gss_client_name, NULL, NULL, NULL,
304	NULL, NULL, NULL);
305	if(check_gss_err(data, gss_major_status,
306	gss_minor_status, "gss_inquire_context")) {
307	gss_delete_sec_context(&gss_status, &gss_context, NULL);
308	gss_release_name(&gss_status, &gss_client_name);
309	failf(data, "Failed to determine user name.");
310	return CURLE_COULDNT_CONNECT;
311	}
312	gss_major_status = gss_display_name(&gss_minor_status, gss_client_name,
313	&gss_send_token, NULL);
314	if(check_gss_err(data, gss_major_status,
315	gss_minor_status, "gss_display_name")) {
316	gss_delete_sec_context(&gss_status, &gss_context, NULL);
317	gss_release_name(&gss_status, &gss_client_name);
318	gss_release_buffer(&gss_status, &gss_send_token);
319	failf(data, "Failed to determine user name.");
320	return CURLE_COULDNT_CONNECT;
321	}
322	user = malloc(gss_send_token.length + 1);
323	if(!user) {
324	gss_delete_sec_context(&gss_status, &gss_context, NULL);
325	gss_release_name(&gss_status, &gss_client_name);
326	gss_release_buffer(&gss_status, &gss_send_token);
327	return CURLE_OUT_OF_MEMORY;
328	}
329
330	memcpy(user, gss_send_token.value, gss_send_token.length);
331	user[gss_send_token.length] = '\0';
332	gss_release_name(&gss_status, &gss_client_name);
333	gss_release_buffer(&gss_status, &gss_send_token);
334	infof(data, "SOCKS5 server authenticated user %s with GSS-API.",user);
335	free(user);
336	user = NULL;
337
338	/* Do encryption */
339	socksreq[0] = 1; /* GSS-API subnegotiation version */
340	socksreq[1] = 2; /* encryption message type */
341
342	gss_enc = 0; /* no data protection */
343	/* do confidentiality protection if supported */
344	if(gss_ret_flags & GSS_C_CONF_FLAG)
345	gss_enc = 2;
346	/* else do integrity protection */
347	else if(gss_ret_flags & GSS_C_INTEG_FLAG)
348	gss_enc = 1;
349
350	infof(data, "SOCKS5 server supports GSS-API %s data protection.",
351	(gss_enc == 0)?"no":((gss_enc==1)?"integrity":"confidentiality"));
352	/* force for the moment to no data protection */
353	gss_enc = 0;
354	/*
355	* Sending the encryption type in clear seems wrong. It should be
356	* protected with gss_seal()/gss_wrap(). See RFC1961 extract below
357	* The NEC reference implementations on which this is based is
358	* therefore at fault
359	*
360	* +------+------+------+.......................+
361	* + ver \| mtyp \| len \| token \|
362	* +------+------+------+.......................+
363	* + 0x01 \| 0x02 \| 0x02 \| up to 2^16 - 1 octets \|
364	* +------+------+------+.......................+
365	*
366	* Where:
367	*
368	* - "ver" is the protocol version number, here 1 to represent the
369	* first version of the SOCKS/GSS-API protocol
370	*
371	* - "mtyp" is the message type, here 2 to represent a protection
372	* -level negotiation message
373	*
374	* - "len" is the length of the "token" field in octets
375	*
376	* - "token" is the GSS-API encapsulated protection level
377	*
378	* The token is produced by encapsulating an octet containing the
379	* required protection level using gss_seal()/gss_wrap() with conf_req
380	* set to FALSE. The token is verified using gss_unseal()/
381	* gss_unwrap().
382	*
383	*/
384	if(data->set.socks5_gssapi_nec) {
385	us_length = htons((short)1);
386	memcpy(socksreq + 2, &us_length, sizeof(short));
387	}
388	else {
389	gss_send_token.length = 1;
390	gss_send_token.value = Curl_memdup(&gss_enc, 1);
391	if(!gss_send_token.value) {
392	gss_delete_sec_context(&gss_status, &gss_context, NULL);
393	return CURLE_OUT_OF_MEMORY;
394	}
395
396	gss_major_status = gss_wrap(&gss_minor_status, gss_context, 0,
397	GSS_C_QOP_DEFAULT, &gss_send_token,
398	&gss_conf_state, &gss_w_token);
399
400	if(check_gss_err(data, gss_major_status, gss_minor_status, "gss_wrap")) {
401	gss_release_buffer(&gss_status, &gss_send_token);
402	gss_release_buffer(&gss_status, &gss_w_token);
403	gss_delete_sec_context(&gss_status, &gss_context, NULL);
404	failf(data, "Failed to wrap GSS-API encryption value into token.");
405	return CURLE_COULDNT_CONNECT;
406	}
407	gss_release_buffer(&gss_status, &gss_send_token);
408
409	us_length = htons((short)gss_w_token.length);
410	memcpy(socksreq + 2, &us_length, sizeof(short));
411	}
412
413	nwritten = Curl_conn_cf_send(cf->next, data, (char *)socksreq, 4, &code);
414	if(code \|\| (4 != nwritten)) {
415	failf(data, "Failed to send GSS-API encryption request.");
416	gss_release_buffer(&gss_status, &gss_w_token);
417	gss_delete_sec_context(&gss_status, &gss_context, NULL);
418	return CURLE_COULDNT_CONNECT;
419	}
420
421	if(data->set.socks5_gssapi_nec) {
422	memcpy(socksreq, &gss_enc, 1);
423	nwritten = Curl_conn_cf_send(cf->next, data, (char *)socksreq, 1, &code);
424	if(code \|\| ( 1 != nwritten)) {
425	failf(data, "Failed to send GSS-API encryption type.");
426	gss_delete_sec_context(&gss_status, &gss_context, NULL);
427	return CURLE_COULDNT_CONNECT;
428	}
429	}
430	else {
431	nwritten = Curl_conn_cf_send(cf->next, data,
432	(char *)gss_w_token.value,
433	gss_w_token.length, &code);
434	if(code \|\| ((ssize_t)gss_w_token.length != nwritten)) {
435	failf(data, "Failed to send GSS-API encryption type.");
436	gss_release_buffer(&gss_status, &gss_w_token);
437	gss_delete_sec_context(&gss_status, &gss_context, NULL);
438	return CURLE_COULDNT_CONNECT;
439	}
440	gss_release_buffer(&gss_status, &gss_w_token);
441	}
442
443	result = Curl_blockread_all(cf, data, (char *)socksreq, 4, &actualread);
444	if(result \|\| (actualread != 4)) {
445	failf(data, "Failed to receive GSS-API encryption response.");
446	gss_delete_sec_context(&gss_status, &gss_context, NULL);
447	return CURLE_COULDNT_CONNECT;
448	}
449
450	/* ignore the first (VER) byte */
451	if(socksreq[1] == 255) { /* status / message type */
452	failf(data, "User was rejected by the SOCKS5 server (%d %d).",
453	socksreq[0], socksreq[1]);
454	gss_delete_sec_context(&gss_status, &gss_context, NULL);
455	return CURLE_COULDNT_CONNECT;
456	}
457
458	if(socksreq[1] != 2) { /* status / message type */
459	failf(data, "Invalid GSS-API encryption response type (%d %d).",
460	socksreq[0], socksreq[1]);
461	gss_delete_sec_context(&gss_status, &gss_context, NULL);
462	return CURLE_COULDNT_CONNECT;
463	}
464
465	memcpy(&us_length, socksreq + 2, sizeof(short));
466	us_length = ntohs(us_length);
467
468	gss_recv_token.length = us_length;
469	gss_recv_token.value = malloc(gss_recv_token.length);
470	if(!gss_recv_token.value) {
471	gss_delete_sec_context(&gss_status, &gss_context, NULL);
472	return CURLE_OUT_OF_MEMORY;
473	}
474	result = Curl_blockread_all(cf, data, (char *)gss_recv_token.value,
475	gss_recv_token.length, &actualread);
476
477	if(result \|\| (actualread != us_length)) {
478	failf(data, "Failed to receive GSS-API encryption type.");
479	gss_release_buffer(&gss_status, &gss_recv_token);
480	gss_delete_sec_context(&gss_status, &gss_context, NULL);
481	return CURLE_COULDNT_CONNECT;
482	}
483
484	if(!data->set.socks5_gssapi_nec) {
485	gss_major_status = gss_unwrap(&gss_minor_status, gss_context,
486	&gss_recv_token, &gss_w_token,
487	0, GSS_C_QOP_DEFAULT);
488
489	if(check_gss_err(data, gss_major_status, gss_minor_status, "gss_unwrap")) {
490	gss_release_buffer(&gss_status, &gss_recv_token);
491	gss_release_buffer(&gss_status, &gss_w_token);
492	gss_delete_sec_context(&gss_status, &gss_context, NULL);
493	failf(data, "Failed to unwrap GSS-API encryption value into token.");
494	return CURLE_COULDNT_CONNECT;
495	}
496	gss_release_buffer(&gss_status, &gss_recv_token);
497
498	if(gss_w_token.length != 1) {
499	failf(data, "Invalid GSS-API encryption response length (%zu).",
500	gss_w_token.length);
501	gss_release_buffer(&gss_status, &gss_w_token);
502	gss_delete_sec_context(&gss_status, &gss_context, NULL);
503	return CURLE_COULDNT_CONNECT;
504	}
505
506	memcpy(socksreq, gss_w_token.value, gss_w_token.length);
507	gss_release_buffer(&gss_status, &gss_w_token);
508	}
509	else {
510	if(gss_recv_token.length != 1) {
511	failf(data, "Invalid GSS-API encryption response length (%zu).",
512	gss_recv_token.length);
513	gss_release_buffer(&gss_status, &gss_recv_token);
514	gss_delete_sec_context(&gss_status, &gss_context, NULL);
515	return CURLE_COULDNT_CONNECT;
516	}
517
518	memcpy(socksreq, gss_recv_token.value, gss_recv_token.length);
519	gss_release_buffer(&gss_status, &gss_recv_token);
520	}
521
522	(void)curlx_nonblock(sock, TRUE);
523
524	infof(data, "SOCKS5 access with%s protection granted.",
525	(socksreq[0] == 0)?"out GSS-API data":
526	((socksreq[0] == 1)?" GSS-API integrity":" GSS-API confidentiality"));
527
528	conn->socks5_gssapi_enctype = socksreq[0];
529	if(socksreq[0] == 0)
530	gss_delete_sec_context(&gss_status, &gss_context, NULL);
531
532	return CURLE_OK;
533	}
534
535	#endif /* HAVE_GSSAPI && !CURL_DISABLE_PROXY */

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source: vbox/trunk/src/libs/curl-8.7.1/lib/socks_gssapi.c@ 104085

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