merge trunk
[bpt/emacs.git] / src / gnutls.c
1 /* GnuTLS glue for GNU Emacs.
2 Copyright (C) 2010-2011 Free Software Foundation, Inc.
3
4 This file is part of GNU Emacs.
5
6 GNU Emacs is free software: you can redistribute it and/or modify
7 it under the terms of the GNU General Public License as published by
8 the Free Software Foundation, either version 3 of the License, or
9 (at your option) any later version.
10
11 GNU Emacs is distributed in the hope that it will be useful,
12 but WITHOUT ANY WARRANTY; without even the implied warranty of
13 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
14 GNU General Public License for more details.
15
16 You should have received a copy of the GNU General Public License
17 along with GNU Emacs. If not, see <http://www.gnu.org/licenses/>. */
18
19 #include <config.h>
20 #include <errno.h>
21 #include <setjmp.h>
22
23 #include "lisp.h"
24 #include "process.h"
25
26 #ifdef HAVE_GNUTLS
27 #include <gnutls/gnutls.h>
28
29 #ifdef WINDOWSNT
30 #include <windows.h>
31 #include "w32.h"
32 #endif
33
34 static int
35 emacs_gnutls_handle_error (gnutls_session_t, int err);
36
37 static Lisp_Object Qgnutls_dll;
38 static Lisp_Object Qgnutls_log_level;
39 static Lisp_Object Qgnutls_code;
40 static Lisp_Object Qgnutls_anon, Qgnutls_x509pki;
41 static Lisp_Object Qgnutls_e_interrupted, Qgnutls_e_again,
42 Qgnutls_e_invalid_session, Qgnutls_e_not_ready_for_handshake;
43 static int gnutls_global_initialized;
44
45 /* The following are for the property list of `gnutls-boot'. */
46 static Lisp_Object Qgnutls_bootprop_priority;
47 static Lisp_Object Qgnutls_bootprop_trustfiles;
48 static Lisp_Object Qgnutls_bootprop_keylist;
49 static Lisp_Object Qgnutls_bootprop_crlfiles;
50 static Lisp_Object Qgnutls_bootprop_callbacks;
51 static Lisp_Object Qgnutls_bootprop_loglevel;
52 static Lisp_Object Qgnutls_bootprop_hostname;
53 static Lisp_Object Qgnutls_bootprop_verify_flags;
54 static Lisp_Object Qgnutls_bootprop_verify_hostname_error;
55
56 /* Callback keys for `gnutls-boot'. Unused currently. */
57 static Lisp_Object Qgnutls_bootprop_callbacks_verify;
58
59 static void gnutls_log_function (int, const char *);
60 static void gnutls_log_function2 (int, const char*, const char*);
61
62 \f
63 #ifdef WINDOWSNT
64
65 /* Macro for defining functions that will be loaded from the GnuTLS DLL. */
66 #define DEF_GNUTLS_FN(rettype,func,args) static rettype (FAR CDECL *fn_##func)args
67
68 /* Macro for loading GnuTLS functions from the library. */
69 #define LOAD_GNUTLS_FN(lib,func) { \
70 fn_##func = (void *) GetProcAddress (lib, #func); \
71 if (!fn_##func) return 0; \
72 }
73
74 DEF_GNUTLS_FN (gnutls_alert_description_t, gnutls_alert_get,
75 (gnutls_session_t));
76 DEF_GNUTLS_FN (const char *, gnutls_alert_get_name,
77 (gnutls_alert_description_t));
78 DEF_GNUTLS_FN (int, gnutls_alert_send_appropriate, (gnutls_session_t, int));
79 DEF_GNUTLS_FN (int, gnutls_anon_allocate_client_credentials,
80 (gnutls_anon_client_credentials_t *));
81 DEF_GNUTLS_FN (void, gnutls_anon_free_client_credentials,
82 (gnutls_anon_client_credentials_t));
83 DEF_GNUTLS_FN (int, gnutls_bye, (gnutls_session_t, gnutls_close_request_t));
84 DEF_GNUTLS_FN (int, gnutls_certificate_allocate_credentials,
85 (gnutls_certificate_credentials_t *));
86 DEF_GNUTLS_FN (void, gnutls_certificate_free_credentials,
87 (gnutls_certificate_credentials_t));
88 DEF_GNUTLS_FN (const gnutls_datum_t *, gnutls_certificate_get_peers,
89 (gnutls_session_t, unsigned int *));
90 DEF_GNUTLS_FN (void, gnutls_certificate_set_verify_flags,
91 (gnutls_certificate_credentials_t, unsigned int));
92 DEF_GNUTLS_FN (int, gnutls_certificate_set_x509_crl_file,
93 (gnutls_certificate_credentials_t, const char *,
94 gnutls_x509_crt_fmt_t));
95 DEF_GNUTLS_FN (int, gnutls_certificate_set_x509_key_file,
96 (gnutls_certificate_credentials_t, const char *, const char *,
97 gnutls_x509_crt_fmt_t));
98 DEF_GNUTLS_FN (int, gnutls_certificate_set_x509_trust_file,
99 (gnutls_certificate_credentials_t, const char *,
100 gnutls_x509_crt_fmt_t));
101 DEF_GNUTLS_FN (gnutls_certificate_type_t, gnutls_certificate_type_get,
102 (gnutls_session_t));
103 DEF_GNUTLS_FN (int, gnutls_certificate_verify_peers2,
104 (gnutls_session_t, unsigned int *));
105 DEF_GNUTLS_FN (int, gnutls_credentials_set,
106 (gnutls_session_t, gnutls_credentials_type_t, void *));
107 DEF_GNUTLS_FN (void, gnutls_deinit, (gnutls_session_t));
108 DEF_GNUTLS_FN (int, gnutls_error_is_fatal, (int));
109 DEF_GNUTLS_FN (int, gnutls_global_init, (void));
110 DEF_GNUTLS_FN (void, gnutls_global_set_log_function, (gnutls_log_func));
111 DEF_GNUTLS_FN (void, gnutls_global_set_log_level, (int));
112 DEF_GNUTLS_FN (void, gnutls_global_set_mem_functions,
113 (gnutls_alloc_function, gnutls_alloc_function,
114 gnutls_is_secure_function, gnutls_realloc_function,
115 gnutls_free_function));
116 DEF_GNUTLS_FN (int, gnutls_handshake, (gnutls_session_t));
117 DEF_GNUTLS_FN (int, gnutls_init, (gnutls_session_t *, gnutls_connection_end_t));
118 DEF_GNUTLS_FN (int, gnutls_priority_set_direct,
119 (gnutls_session_t, const char *, const char **));
120 DEF_GNUTLS_FN (size_t, gnutls_record_check_pending, (gnutls_session_t));
121 DEF_GNUTLS_FN (ssize_t, gnutls_record_recv, (gnutls_session_t, void *, size_t));
122 DEF_GNUTLS_FN (ssize_t, gnutls_record_send,
123 (gnutls_session_t, const void *, size_t));
124 DEF_GNUTLS_FN (const char *, gnutls_strerror, (int));
125 DEF_GNUTLS_FN (void, gnutls_transport_set_errno, (gnutls_session_t, int));
126 DEF_GNUTLS_FN (void, gnutls_transport_set_lowat, (gnutls_session_t, int));
127 DEF_GNUTLS_FN (void, gnutls_transport_set_ptr2,
128 (gnutls_session_t, gnutls_transport_ptr_t,
129 gnutls_transport_ptr_t));
130 DEF_GNUTLS_FN (void, gnutls_transport_set_pull_function,
131 (gnutls_session_t, gnutls_pull_func));
132 DEF_GNUTLS_FN (void, gnutls_transport_set_push_function,
133 (gnutls_session_t, gnutls_push_func));
134 DEF_GNUTLS_FN (int, gnutls_x509_crt_check_hostname,
135 (gnutls_x509_crt_t, const char *));
136 DEF_GNUTLS_FN (void, gnutls_x509_crt_deinit, (gnutls_x509_crt_t));
137 DEF_GNUTLS_FN (int, gnutls_x509_crt_import,
138 (gnutls_x509_crt_t, const gnutls_datum_t *,
139 gnutls_x509_crt_fmt_t));
140 DEF_GNUTLS_FN (int, gnutls_x509_crt_init, (gnutls_x509_crt_t *));
141
142 static int
143 init_gnutls_functions (Lisp_Object libraries)
144 {
145 HMODULE library;
146
147 if (!(library = w32_delayed_load (libraries, Qgnutls_dll)))
148 {
149 GNUTLS_LOG (1, 1, "GnuTLS library not found");
150 return 0;
151 }
152
153 LOAD_GNUTLS_FN (library, gnutls_alert_get);
154 LOAD_GNUTLS_FN (library, gnutls_alert_get_name);
155 LOAD_GNUTLS_FN (library, gnutls_alert_send_appropriate);
156 LOAD_GNUTLS_FN (library, gnutls_anon_allocate_client_credentials);
157 LOAD_GNUTLS_FN (library, gnutls_anon_free_client_credentials);
158 LOAD_GNUTLS_FN (library, gnutls_bye);
159 LOAD_GNUTLS_FN (library, gnutls_certificate_allocate_credentials);
160 LOAD_GNUTLS_FN (library, gnutls_certificate_free_credentials);
161 LOAD_GNUTLS_FN (library, gnutls_certificate_get_peers);
162 LOAD_GNUTLS_FN (library, gnutls_certificate_set_verify_flags);
163 LOAD_GNUTLS_FN (library, gnutls_certificate_set_x509_crl_file);
164 LOAD_GNUTLS_FN (library, gnutls_certificate_set_x509_key_file);
165 LOAD_GNUTLS_FN (library, gnutls_certificate_set_x509_trust_file);
166 LOAD_GNUTLS_FN (library, gnutls_certificate_type_get);
167 LOAD_GNUTLS_FN (library, gnutls_certificate_verify_peers2);
168 LOAD_GNUTLS_FN (library, gnutls_credentials_set);
169 LOAD_GNUTLS_FN (library, gnutls_deinit);
170 LOAD_GNUTLS_FN (library, gnutls_error_is_fatal);
171 LOAD_GNUTLS_FN (library, gnutls_global_init);
172 LOAD_GNUTLS_FN (library, gnutls_global_set_log_function);
173 LOAD_GNUTLS_FN (library, gnutls_global_set_log_level);
174 LOAD_GNUTLS_FN (library, gnutls_global_set_mem_functions);
175 LOAD_GNUTLS_FN (library, gnutls_handshake);
176 LOAD_GNUTLS_FN (library, gnutls_init);
177 LOAD_GNUTLS_FN (library, gnutls_priority_set_direct);
178 LOAD_GNUTLS_FN (library, gnutls_record_check_pending);
179 LOAD_GNUTLS_FN (library, gnutls_record_recv);
180 LOAD_GNUTLS_FN (library, gnutls_record_send);
181 LOAD_GNUTLS_FN (library, gnutls_strerror);
182 LOAD_GNUTLS_FN (library, gnutls_transport_set_errno);
183 LOAD_GNUTLS_FN (library, gnutls_transport_set_lowat);
184 LOAD_GNUTLS_FN (library, gnutls_transport_set_ptr2);
185 LOAD_GNUTLS_FN (library, gnutls_transport_set_pull_function);
186 LOAD_GNUTLS_FN (library, gnutls_transport_set_push_function);
187 LOAD_GNUTLS_FN (library, gnutls_x509_crt_check_hostname);
188 LOAD_GNUTLS_FN (library, gnutls_x509_crt_deinit);
189 LOAD_GNUTLS_FN (library, gnutls_x509_crt_import);
190 LOAD_GNUTLS_FN (library, gnutls_x509_crt_init);
191
192 GNUTLS_LOG2 (1, 1, "GnuTLS library loaded:",
193 SDATA (Fget (Qgnutls_dll, QCloaded_from)));
194 return 1;
195 }
196
197 #else /* !WINDOWSNT */
198
199 #define fn_gnutls_alert_get gnutls_alert_get
200 #define fn_gnutls_alert_get_name gnutls_alert_get_name
201 #define fn_gnutls_alert_send_appropriate gnutls_alert_send_appropriate
202 #define fn_gnutls_anon_allocate_client_credentials gnutls_anon_allocate_client_credentials
203 #define fn_gnutls_anon_free_client_credentials gnutls_anon_free_client_credentials
204 #define fn_gnutls_bye gnutls_bye
205 #define fn_gnutls_certificate_allocate_credentials gnutls_certificate_allocate_credentials
206 #define fn_gnutls_certificate_free_credentials gnutls_certificate_free_credentials
207 #define fn_gnutls_certificate_get_peers gnutls_certificate_get_peers
208 #define fn_gnutls_certificate_set_verify_flags gnutls_certificate_set_verify_flags
209 #define fn_gnutls_certificate_set_x509_crl_file gnutls_certificate_set_x509_crl_file
210 #define fn_gnutls_certificate_set_x509_key_file gnutls_certificate_set_x509_key_file
211 #define fn_gnutls_certificate_set_x509_trust_file gnutls_certificate_set_x509_trust_file
212 #define fn_gnutls_certificate_type_get gnutls_certificate_type_get
213 #define fn_gnutls_certificate_verify_peers2 gnutls_certificate_verify_peers2
214 #define fn_gnutls_credentials_set gnutls_credentials_set
215 #define fn_gnutls_deinit gnutls_deinit
216 #define fn_gnutls_error_is_fatal gnutls_error_is_fatal
217 #define fn_gnutls_global_init gnutls_global_init
218 #define fn_gnutls_global_set_log_function gnutls_global_set_log_function
219 #define fn_gnutls_global_set_log_level gnutls_global_set_log_level
220 #define fn_gnutls_global_set_mem_functions gnutls_global_set_mem_functions
221 #define fn_gnutls_handshake gnutls_handshake
222 #define fn_gnutls_init gnutls_init
223 #define fn_gnutls_priority_set_direct gnutls_priority_set_direct
224 #define fn_gnutls_record_check_pending gnutls_record_check_pending
225 #define fn_gnutls_record_recv gnutls_record_recv
226 #define fn_gnutls_record_send gnutls_record_send
227 #define fn_gnutls_strerror gnutls_strerror
228 #define fn_gnutls_transport_set_errno gnutls_transport_set_errno
229 #define fn_gnutls_transport_set_ptr2 gnutls_transport_set_ptr2
230 #define fn_gnutls_x509_crt_check_hostname gnutls_x509_crt_check_hostname
231 #define fn_gnutls_x509_crt_deinit gnutls_x509_crt_deinit
232 #define fn_gnutls_x509_crt_import gnutls_x509_crt_import
233 #define fn_gnutls_x509_crt_init gnutls_x509_crt_init
234
235 #endif /* !WINDOWSNT */
236
237 \f
238 static void
239 gnutls_log_function (int level, const char* string)
240 {
241 message ("gnutls.c: [%d] %s", level, string);
242 }
243
244 static void
245 gnutls_log_function2 (int level, const char* string, const char* extra)
246 {
247 message ("gnutls.c: [%d] %s %s", level, string, extra);
248 }
249
250 static int
251 emacs_gnutls_handshake (struct Lisp_Process *proc)
252 {
253 gnutls_session_t state = proc->gnutls_state;
254 int ret;
255
256 if (proc->gnutls_initstage < GNUTLS_STAGE_HANDSHAKE_CANDO)
257 return -1;
258
259 if (proc->gnutls_initstage < GNUTLS_STAGE_TRANSPORT_POINTERS_SET)
260 {
261 #ifdef WINDOWSNT
262 /* On W32 we cannot transfer socket handles between different runtime
263 libraries, so we tell GnuTLS to use our special push/pull
264 functions. */
265 fn_gnutls_transport_set_ptr2 (state,
266 (gnutls_transport_ptr_t) proc,
267 (gnutls_transport_ptr_t) proc);
268 fn_gnutls_transport_set_push_function (state, &emacs_gnutls_push);
269 fn_gnutls_transport_set_pull_function (state, &emacs_gnutls_pull);
270
271 /* For non blocking sockets or other custom made pull/push
272 functions the gnutls_transport_set_lowat must be called, with
273 a zero low water mark value. (GnuTLS 2.10.4 documentation)
274
275 (Note: this is probably not strictly necessary as the lowat
276 value is only used when no custom pull/push functions are
277 set.) */
278 fn_gnutls_transport_set_lowat (state, 0);
279 #else
280 /* This is how GnuTLS takes sockets: as file descriptors passed
281 in. For an Emacs process socket, infd and outfd are the
282 same but we use this two-argument version for clarity. */
283 fn_gnutls_transport_set_ptr2 (state,
284 (gnutls_transport_ptr_t) (long) proc->infd,
285 (gnutls_transport_ptr_t) (long) proc->outfd);
286 #endif
287
288 proc->gnutls_initstage = GNUTLS_STAGE_TRANSPORT_POINTERS_SET;
289 }
290
291 do
292 {
293 ret = fn_gnutls_handshake (state);
294 emacs_gnutls_handle_error (state, ret);
295 }
296 while (ret < 0 && fn_gnutls_error_is_fatal (ret) == 0);
297
298 proc->gnutls_initstage = GNUTLS_STAGE_HANDSHAKE_TRIED;
299
300 if (ret == GNUTLS_E_SUCCESS)
301 {
302 /* Here we're finally done. */
303 proc->gnutls_initstage = GNUTLS_STAGE_READY;
304 }
305 else
306 {
307 fn_gnutls_alert_send_appropriate (state, ret);
308 }
309 return ret;
310 }
311
312 int
313 emacs_gnutls_record_check_pending (gnutls_session_t state)
314 {
315 return fn_gnutls_record_check_pending (state);
316 }
317
318 void
319 emacs_gnutls_transport_set_errno (gnutls_session_t state, int err)
320 {
321 fn_gnutls_transport_set_errno (state, err);
322 }
323
324 EMACS_INT
325 emacs_gnutls_write (struct Lisp_Process *proc, const char *buf, EMACS_INT nbyte)
326 {
327 ssize_t rtnval = 0;
328 EMACS_INT bytes_written;
329 gnutls_session_t state = proc->gnutls_state;
330
331 if (proc->gnutls_initstage != GNUTLS_STAGE_READY) {
332 #ifdef EWOULDBLOCK
333 errno = EWOULDBLOCK;
334 #endif
335 #ifdef EAGAIN
336 errno = EAGAIN;
337 #endif
338 return 0;
339 }
340
341 bytes_written = 0;
342
343 while (nbyte > 0)
344 {
345 rtnval = fn_gnutls_record_send (state, buf, nbyte);
346
347 if (rtnval < 0)
348 {
349 if (rtnval == GNUTLS_E_AGAIN || rtnval == GNUTLS_E_INTERRUPTED)
350 continue;
351 else
352 break;
353 }
354
355 buf += rtnval;
356 nbyte -= rtnval;
357 bytes_written += rtnval;
358 }
359
360 emacs_gnutls_handle_error (state, rtnval);
361 return (bytes_written);
362 }
363
364 EMACS_INT
365 emacs_gnutls_read (struct Lisp_Process *proc, char *buf, EMACS_INT nbyte)
366 {
367 ssize_t rtnval;
368 gnutls_session_t state = proc->gnutls_state;
369
370 if (proc->gnutls_initstage != GNUTLS_STAGE_READY)
371 {
372 emacs_gnutls_handshake (proc);
373 return -1;
374 }
375 rtnval = fn_gnutls_record_recv (state, buf, nbyte);
376 if (rtnval >= 0)
377 return rtnval;
378 else if (emacs_gnutls_handle_error (state, rtnval) == 0)
379 /* non-fatal error */
380 return -1;
381 else {
382 /* a fatal error occurred */
383 return 0;
384 }
385 }
386
387 /* report a GnuTLS error to the user.
388 Returns zero if the error code was successfully handled. */
389 static int
390 emacs_gnutls_handle_error (gnutls_session_t session, int err)
391 {
392 Lisp_Object gnutls_log_level = Fsymbol_value (Qgnutls_log_level);
393 int max_log_level = 0;
394
395 int ret;
396 const char *str;
397
398 /* TODO: use a Lisp_Object generated by gnutls_make_error? */
399 if (err >= 0)
400 return 0;
401
402 if (NUMBERP (gnutls_log_level))
403 max_log_level = XINT (gnutls_log_level);
404
405 /* TODO: use gnutls-error-fatalp and gnutls-error-string. */
406
407 str = fn_gnutls_strerror (err);
408 if (!str)
409 str = "unknown";
410
411 if (fn_gnutls_error_is_fatal (err))
412 {
413 ret = err;
414 GNUTLS_LOG2 (0, max_log_level, "fatal error:", str);
415 }
416 else
417 {
418 ret = 0;
419 GNUTLS_LOG2 (1, max_log_level, "non-fatal error:", str);
420 /* TODO: EAGAIN AKA Qgnutls_e_again should be level 2. */
421 }
422
423 if (err == GNUTLS_E_WARNING_ALERT_RECEIVED
424 || err == GNUTLS_E_FATAL_ALERT_RECEIVED)
425 {
426 int alert = fn_gnutls_alert_get (session);
427 int level = (err == GNUTLS_E_FATAL_ALERT_RECEIVED) ? 0 : 1;
428 str = fn_gnutls_alert_get_name (alert);
429 if (!str)
430 str = "unknown";
431
432 GNUTLS_LOG2 (level, max_log_level, "Received alert: ", str);
433 }
434 return ret;
435 }
436
437 /* convert an integer error to a Lisp_Object; it will be either a
438 known symbol like `gnutls_e_interrupted' and `gnutls_e_again' or
439 simply the integer value of the error. GNUTLS_E_SUCCESS is mapped
440 to Qt. */
441 static Lisp_Object
442 gnutls_make_error (int err)
443 {
444 switch (err)
445 {
446 case GNUTLS_E_SUCCESS:
447 return Qt;
448 case GNUTLS_E_AGAIN:
449 return Qgnutls_e_again;
450 case GNUTLS_E_INTERRUPTED:
451 return Qgnutls_e_interrupted;
452 case GNUTLS_E_INVALID_SESSION:
453 return Qgnutls_e_invalid_session;
454 }
455
456 return make_number (err);
457 }
458
459 DEFUN ("gnutls-get-initstage", Fgnutls_get_initstage, Sgnutls_get_initstage, 1, 1, 0,
460 doc: /* Return the GnuTLS init stage of process PROC.
461 See also `gnutls-boot'. */)
462 (Lisp_Object proc)
463 {
464 CHECK_PROCESS (proc);
465
466 return make_number (GNUTLS_INITSTAGE (proc));
467 }
468
469 DEFUN ("gnutls-errorp", Fgnutls_errorp, Sgnutls_errorp, 1, 1, 0,
470 doc: /* Return t if ERROR indicates a GnuTLS problem.
471 ERROR is an integer or a symbol with an integer `gnutls-code' property.
472 usage: (gnutls-errorp ERROR) */)
473 (Lisp_Object err)
474 {
475 if (EQ (err, Qt)) return Qnil;
476
477 return Qt;
478 }
479
480 DEFUN ("gnutls-error-fatalp", Fgnutls_error_fatalp, Sgnutls_error_fatalp, 1, 1, 0,
481 doc: /* Check if ERROR is fatal.
482 ERROR is an integer or a symbol with an integer `gnutls-code' property.
483 usage: (gnutls-error-fatalp ERROR) */)
484 (Lisp_Object err)
485 {
486 Lisp_Object code;
487
488 if (EQ (err, Qt)) return Qnil;
489
490 if (SYMBOLP (err))
491 {
492 code = Fget (err, Qgnutls_code);
493 if (NUMBERP (code))
494 {
495 err = code;
496 }
497 else
498 {
499 error ("Symbol has no numeric gnutls-code property");
500 }
501 }
502
503 if (!NUMBERP (err))
504 error ("Not an error symbol or code");
505
506 if (0 == fn_gnutls_error_is_fatal (XINT (err)))
507 return Qnil;
508
509 return Qt;
510 }
511
512 DEFUN ("gnutls-error-string", Fgnutls_error_string, Sgnutls_error_string, 1, 1, 0,
513 doc: /* Return a description of ERROR.
514 ERROR is an integer or a symbol with an integer `gnutls-code' property.
515 usage: (gnutls-error-string ERROR) */)
516 (Lisp_Object err)
517 {
518 Lisp_Object code;
519
520 if (EQ (err, Qt)) return build_string ("Not an error");
521
522 if (SYMBOLP (err))
523 {
524 code = Fget (err, Qgnutls_code);
525 if (NUMBERP (code))
526 {
527 err = code;
528 }
529 else
530 {
531 return build_string ("Symbol has no numeric gnutls-code property");
532 }
533 }
534
535 if (!NUMBERP (err))
536 return build_string ("Not an error symbol or code");
537
538 return build_string (fn_gnutls_strerror (XINT (err)));
539 }
540
541 DEFUN ("gnutls-deinit", Fgnutls_deinit, Sgnutls_deinit, 1, 1, 0,
542 doc: /* Deallocate GnuTLS resources associated with process PROC.
543 See also `gnutls-init'. */)
544 (Lisp_Object proc)
545 {
546 gnutls_session_t state;
547
548 CHECK_PROCESS (proc);
549 state = XPROCESS (proc)->gnutls_state;
550
551 if (GNUTLS_INITSTAGE (proc) >= GNUTLS_STAGE_INIT)
552 {
553 fn_gnutls_deinit (state);
554 GNUTLS_INITSTAGE (proc) = GNUTLS_STAGE_INIT - 1;
555 }
556
557 return Qt;
558 }
559
560 DEFUN ("gnutls-available-p", Fgnutls_available_p, Sgnutls_available_p, 0, 0, 0,
561 doc: /* Return t if GnuTLS is available in this instance of Emacs. */)
562 (void)
563 {
564 #ifdef WINDOWSNT
565 Lisp_Object found = Fassq (Qgnutls_dll, Vlibrary_cache);
566 if (CONSP (found))
567 return XCDR (found);
568 else
569 {
570 Lisp_Object status;
571 status = init_gnutls_functions (Vdynamic_library_alist) ? Qt : Qnil;
572 Vlibrary_cache = Fcons (Fcons (Qgnutls_dll, status), Vlibrary_cache);
573 return status;
574 }
575 #else
576 return Qt;
577 #endif
578 }
579
580
581 /* Initializes global GnuTLS state to defaults.
582 Call `gnutls-global-deinit' when GnuTLS usage is no longer needed.
583 Returns zero on success. */
584 static Lisp_Object
585 emacs_gnutls_global_init (void)
586 {
587 int ret = GNUTLS_E_SUCCESS;
588
589 if (!gnutls_global_initialized)
590 {
591 fn_gnutls_global_set_mem_functions (xmalloc, xmalloc, NULL,
592 xrealloc, xfree);
593 ret = fn_gnutls_global_init ();
594 }
595 gnutls_global_initialized = 1;
596
597 return gnutls_make_error (ret);
598 }
599
600 #if 0
601 /* Deinitializes global GnuTLS state.
602 See also `gnutls-global-init'. */
603 static Lisp_Object
604 emacs_gnutls_global_deinit (void)
605 {
606 if (gnutls_global_initialized)
607 gnutls_global_deinit ();
608
609 gnutls_global_initialized = 0;
610
611 return gnutls_make_error (GNUTLS_E_SUCCESS);
612 }
613 #endif
614
615 DEFUN ("gnutls-boot", Fgnutls_boot, Sgnutls_boot, 3, 3, 0,
616 doc: /* Initialize GnuTLS client for process PROC with TYPE+PROPLIST.
617 Currently only client mode is supported. Returns a success/failure
618 value you can check with `gnutls-errorp'.
619
620 TYPE is a symbol, either `gnutls-anon' or `gnutls-x509pki'.
621 PROPLIST is a property list with the following keys:
622
623 :hostname is a string naming the remote host.
624
625 :priority is a GnuTLS priority string, defaults to "NORMAL".
626
627 :trustfiles is a list of PEM-encoded trust files for `gnutls-x509pki'.
628
629 :crlfiles is a list of PEM-encoded CRL lists for `gnutls-x509pki'.
630
631 :keylist is an alist of PEM-encoded key files and PEM-encoded
632 certificates for `gnutls-x509pki'.
633
634 :callbacks is an alist of callback functions, see below.
635
636 :loglevel is the debug level requested from GnuTLS, try 4.
637
638 :verify-flags is a bitset as per GnuTLS'
639 gnutls_certificate_set_verify_flags.
640
641 :verify-hostname-error, if non-nil, makes a hostname mismatch an
642 error. Otherwise it will be just a warning.
643
644 The debug level will be set for this process AND globally for GnuTLS.
645 So if you set it higher or lower at any point, it affects global
646 debugging.
647
648 Note that the priority is set on the client. The server does not use
649 the protocols's priority except for disabling protocols that were not
650 specified.
651
652 Processes must be initialized with this function before other GnuTLS
653 functions are used. This function allocates resources which can only
654 be deallocated by calling `gnutls-deinit' or by calling it again.
655
656 The callbacks alist can have a `verify' key, associated with a
657 verification function (UNUSED).
658
659 Each authentication type may need additional information in order to
660 work. For X.509 PKI (`gnutls-x509pki'), you probably need at least
661 one trustfile (usually a CA bundle). */)
662 (Lisp_Object proc, Lisp_Object type, Lisp_Object proplist)
663 {
664 int ret = GNUTLS_E_SUCCESS;
665
666 int max_log_level = 0;
667
668 /* TODO: GNUTLS_X509_FMT_DER is also an option. */
669 int file_format = GNUTLS_X509_FMT_PEM;
670
671 unsigned int gnutls_verify_flags = GNUTLS_VERIFY_ALLOW_X509_V1_CA_CRT;
672 gnutls_x509_crt_t gnutls_verify_cert;
673 unsigned int gnutls_verify_cert_list_size;
674 const gnutls_datum_t *gnutls_verify_cert_list;
675
676 gnutls_session_t state;
677 gnutls_certificate_credentials_t x509_cred;
678 gnutls_anon_client_credentials_t anon_cred;
679 Lisp_Object global_init;
680 char const *priority_string_ptr = "NORMAL"; /* default priority string. */
681 Lisp_Object tail;
682 unsigned int peer_verification;
683 char* c_hostname;
684
685 /* Placeholders for the property list elements. */
686 Lisp_Object priority_string;
687 Lisp_Object trustfiles;
688 Lisp_Object crlfiles;
689 Lisp_Object keylist;
690 /* Lisp_Object callbacks; */
691 Lisp_Object loglevel;
692 Lisp_Object hostname;
693 Lisp_Object verify_flags;
694 /* Lisp_Object verify_error; */
695 Lisp_Object verify_hostname_error;
696
697 CHECK_PROCESS (proc);
698 CHECK_SYMBOL (type);
699 CHECK_LIST (proplist);
700
701 if (NILP (Fgnutls_available_p ()))
702 {
703 error ("GnuTLS not available");
704 return gnutls_make_error (GNUTLS_EMACS_ERROR_NOT_LOADED);
705 }
706
707 hostname = Fplist_get (proplist, Qgnutls_bootprop_hostname);
708 priority_string = Fplist_get (proplist, Qgnutls_bootprop_priority);
709 trustfiles = Fplist_get (proplist, Qgnutls_bootprop_trustfiles);
710 keylist = Fplist_get (proplist, Qgnutls_bootprop_keylist);
711 crlfiles = Fplist_get (proplist, Qgnutls_bootprop_crlfiles);
712 /* callbacks = Fplist_get (proplist, Qgnutls_bootprop_callbacks); */
713 loglevel = Fplist_get (proplist, Qgnutls_bootprop_loglevel);
714 verify_flags = Fplist_get (proplist, Qgnutls_bootprop_verify_flags);
715 /* verify_error = Fplist_get (proplist, Qgnutls_bootprop_verify_error); */
716 verify_hostname_error = Fplist_get (proplist, Qgnutls_bootprop_verify_hostname_error);
717
718 if (!STRINGP (hostname))
719 error ("gnutls-boot: invalid :hostname parameter");
720
721 c_hostname = SSDATA (hostname);
722
723 state = XPROCESS (proc)->gnutls_state;
724 XPROCESS (proc)->gnutls_p = 1;
725
726 if (NUMBERP (loglevel))
727 {
728 fn_gnutls_global_set_log_function (gnutls_log_function);
729 fn_gnutls_global_set_log_level (XINT (loglevel));
730 max_log_level = XINT (loglevel);
731 XPROCESS (proc)->gnutls_log_level = max_log_level;
732 }
733
734 /* always initialize globals. */
735 global_init = emacs_gnutls_global_init ();
736 if (! NILP (Fgnutls_errorp (global_init)))
737 return global_init;
738
739 /* deinit and free resources. */
740 if (GNUTLS_INITSTAGE (proc) >= GNUTLS_STAGE_CRED_ALLOC)
741 {
742 GNUTLS_LOG (1, max_log_level, "deallocating credentials");
743
744 if (EQ (type, Qgnutls_x509pki))
745 {
746 GNUTLS_LOG (2, max_log_level, "deallocating x509 credentials");
747 x509_cred = XPROCESS (proc)->gnutls_x509_cred;
748 fn_gnutls_certificate_free_credentials (x509_cred);
749 }
750 else if (EQ (type, Qgnutls_anon))
751 {
752 GNUTLS_LOG (2, max_log_level, "deallocating anon credentials");
753 anon_cred = XPROCESS (proc)->gnutls_anon_cred;
754 fn_gnutls_anon_free_client_credentials (anon_cred);
755 }
756 else
757 {
758 error ("unknown credential type");
759 ret = GNUTLS_EMACS_ERROR_INVALID_TYPE;
760 }
761
762 if (GNUTLS_INITSTAGE (proc) >= GNUTLS_STAGE_INIT)
763 {
764 GNUTLS_LOG (1, max_log_level, "deallocating x509 credentials");
765 Fgnutls_deinit (proc);
766 }
767 }
768
769 GNUTLS_INITSTAGE (proc) = GNUTLS_STAGE_EMPTY;
770
771 GNUTLS_LOG (1, max_log_level, "allocating credentials");
772
773 if (EQ (type, Qgnutls_x509pki))
774 {
775 GNUTLS_LOG (2, max_log_level, "allocating x509 credentials");
776 x509_cred = XPROCESS (proc)->gnutls_x509_cred;
777 fn_gnutls_certificate_allocate_credentials (&x509_cred);
778
779 if (NUMBERP (verify_flags))
780 {
781 gnutls_verify_flags = XINT (verify_flags);
782 GNUTLS_LOG (2, max_log_level, "setting verification flags");
783 }
784 else if (NILP (verify_flags))
785 {
786 /* The default is already GNUTLS_VERIFY_ALLOW_X509_V1_CA_CRT. */
787 GNUTLS_LOG (2, max_log_level, "using default verification flags");
788 }
789 else
790 {
791 /* The default is already GNUTLS_VERIFY_ALLOW_X509_V1_CA_CRT. */
792 GNUTLS_LOG (2, max_log_level, "ignoring invalid verify-flags");
793 }
794 fn_gnutls_certificate_set_verify_flags (x509_cred, gnutls_verify_flags);
795 }
796 else if (EQ (type, Qgnutls_anon))
797 {
798 GNUTLS_LOG (2, max_log_level, "allocating anon credentials");
799 anon_cred = XPROCESS (proc)->gnutls_anon_cred;
800 fn_gnutls_anon_allocate_client_credentials (&anon_cred);
801 }
802 else
803 {
804 error ("unknown credential type");
805 ret = GNUTLS_EMACS_ERROR_INVALID_TYPE;
806 }
807
808 if (ret < GNUTLS_E_SUCCESS)
809 return gnutls_make_error (ret);
810
811 GNUTLS_INITSTAGE (proc) = GNUTLS_STAGE_CRED_ALLOC;
812
813 if (EQ (type, Qgnutls_x509pki))
814 {
815 for (tail = trustfiles; !NILP (tail); tail = Fcdr (tail))
816 {
817 Lisp_Object trustfile = Fcar (tail);
818 if (STRINGP (trustfile))
819 {
820 GNUTLS_LOG2 (1, max_log_level, "setting the trustfile: ",
821 SSDATA (trustfile));
822 ret = fn_gnutls_certificate_set_x509_trust_file
823 (x509_cred,
824 SSDATA (trustfile),
825 file_format);
826
827 if (ret < GNUTLS_E_SUCCESS)
828 return gnutls_make_error (ret);
829 }
830 else
831 {
832 error ("Sorry, GnuTLS can't use non-string trustfile %s",
833 SDATA (trustfile));
834 }
835 }
836
837 for (tail = crlfiles; !NILP (tail); tail = Fcdr (tail))
838 {
839 Lisp_Object crlfile = Fcar (tail);
840 if (STRINGP (crlfile))
841 {
842 GNUTLS_LOG2 (1, max_log_level, "setting the CRL file: ",
843 SSDATA (crlfile));
844 ret = fn_gnutls_certificate_set_x509_crl_file
845 (x509_cred,
846 SSDATA (crlfile),
847 file_format);
848
849 if (ret < GNUTLS_E_SUCCESS)
850 return gnutls_make_error (ret);
851 }
852 else
853 {
854 error ("Sorry, GnuTLS can't use non-string CRL file %s",
855 SDATA (crlfile));
856 }
857 }
858
859 for (tail = keylist; !NILP (tail); tail = Fcdr (tail))
860 {
861 Lisp_Object keyfile = Fcar (Fcar (tail));
862 Lisp_Object certfile = Fcar (Fcdr (tail));
863 if (STRINGP (keyfile) && STRINGP (certfile))
864 {
865 GNUTLS_LOG2 (1, max_log_level, "setting the client key file: ",
866 SSDATA (keyfile));
867 GNUTLS_LOG2 (1, max_log_level, "setting the client cert file: ",
868 SSDATA (certfile));
869 ret = fn_gnutls_certificate_set_x509_key_file
870 (x509_cred,
871 SSDATA (certfile),
872 SSDATA (keyfile),
873 file_format);
874
875 if (ret < GNUTLS_E_SUCCESS)
876 return gnutls_make_error (ret);
877 }
878 else
879 {
880 if (STRINGP (keyfile))
881 error ("Sorry, GnuTLS can't use non-string client cert file %s",
882 SDATA (certfile));
883 else
884 error ("Sorry, GnuTLS can't use non-string client key file %s",
885 SDATA (keyfile));
886 }
887 }
888 }
889
890 GNUTLS_INITSTAGE (proc) = GNUTLS_STAGE_FILES;
891
892 GNUTLS_LOG (1, max_log_level, "gnutls callbacks");
893
894 GNUTLS_INITSTAGE (proc) = GNUTLS_STAGE_CALLBACKS;
895
896 #ifdef HAVE_GNUTLS_CALLBACK_CERTIFICATE_VERIFY
897 #else
898 #endif
899
900 GNUTLS_LOG (1, max_log_level, "gnutls_init");
901
902 ret = fn_gnutls_init (&state, GNUTLS_CLIENT);
903
904 if (ret < GNUTLS_E_SUCCESS)
905 return gnutls_make_error (ret);
906
907 XPROCESS (proc)->gnutls_state = state;
908
909 GNUTLS_INITSTAGE (proc) = GNUTLS_STAGE_INIT;
910
911 if (STRINGP (priority_string))
912 {
913 priority_string_ptr = SSDATA (priority_string);
914 GNUTLS_LOG2 (1, max_log_level, "got non-default priority string:",
915 priority_string_ptr);
916 }
917 else
918 {
919 GNUTLS_LOG2 (1, max_log_level, "using default priority string:",
920 priority_string_ptr);
921 }
922
923 GNUTLS_LOG (1, max_log_level, "setting the priority string");
924
925 ret = fn_gnutls_priority_set_direct (state,
926 priority_string_ptr,
927 NULL);
928
929 if (ret < GNUTLS_E_SUCCESS)
930 return gnutls_make_error (ret);
931
932 GNUTLS_INITSTAGE (proc) = GNUTLS_STAGE_PRIORITY;
933
934 if (EQ (type, Qgnutls_x509pki))
935 {
936 ret = fn_gnutls_credentials_set (state, GNUTLS_CRD_CERTIFICATE, x509_cred);
937 }
938 else if (EQ (type, Qgnutls_anon))
939 {
940 ret = fn_gnutls_credentials_set (state, GNUTLS_CRD_ANON, anon_cred);
941 }
942 else
943 {
944 error ("unknown credential type");
945 ret = GNUTLS_EMACS_ERROR_INVALID_TYPE;
946 }
947
948 if (ret < GNUTLS_E_SUCCESS)
949 return gnutls_make_error (ret);
950
951 XPROCESS (proc)->gnutls_anon_cred = anon_cred;
952 XPROCESS (proc)->gnutls_x509_cred = x509_cred;
953 XPROCESS (proc)->gnutls_cred_type = type;
954
955 GNUTLS_INITSTAGE (proc) = GNUTLS_STAGE_CRED_SET;
956
957 ret = emacs_gnutls_handshake (XPROCESS (proc));
958
959 if (ret < GNUTLS_E_SUCCESS)
960 return gnutls_make_error (ret);
961
962 /* Now verify the peer, following
963 http://www.gnu.org/software/gnutls/manual/html_node/Verifying-peer_0027s-certificate.html.
964 The peer should present at least one certificate in the chain; do a
965 check of the certificate's hostname with
966 gnutls_x509_crt_check_hostname() against :hostname. */
967
968 ret = fn_gnutls_certificate_verify_peers2 (state, &peer_verification);
969
970 if (ret < GNUTLS_E_SUCCESS)
971 return gnutls_make_error (ret);
972
973 if (XINT (loglevel) > 0 && peer_verification & GNUTLS_CERT_INVALID)
974 message ("%s certificate could not be verified.",
975 c_hostname);
976
977 if (peer_verification & GNUTLS_CERT_REVOKED)
978 GNUTLS_LOG2 (1, max_log_level, "certificate was revoked (CRL):",
979 c_hostname);
980
981 if (peer_verification & GNUTLS_CERT_SIGNER_NOT_FOUND)
982 GNUTLS_LOG2 (1, max_log_level, "certificate signer was not found:",
983 c_hostname);
984
985 if (peer_verification & GNUTLS_CERT_SIGNER_NOT_CA)
986 GNUTLS_LOG2 (1, max_log_level, "certificate signer is not a CA:",
987 c_hostname);
988
989 if (peer_verification & GNUTLS_CERT_INSECURE_ALGORITHM)
990 GNUTLS_LOG2 (1, max_log_level,
991 "certificate was signed with an insecure algorithm:",
992 c_hostname);
993
994 if (peer_verification & GNUTLS_CERT_NOT_ACTIVATED)
995 GNUTLS_LOG2 (1, max_log_level, "certificate is not yet activated:",
996 c_hostname);
997
998 if (peer_verification & GNUTLS_CERT_EXPIRED)
999 GNUTLS_LOG2 (1, max_log_level, "certificate has expired:",
1000 c_hostname);
1001
1002 if (peer_verification != 0)
1003 {
1004 if (NILP (verify_hostname_error))
1005 {
1006 GNUTLS_LOG2 (1, max_log_level, "certificate validation failed:",
1007 c_hostname);
1008 }
1009 else
1010 {
1011 error ("Certificate validation failed %s, verification code %d",
1012 c_hostname, peer_verification);
1013 }
1014 }
1015
1016 /* Up to here the process is the same for X.509 certificates and
1017 OpenPGP keys. From now on X.509 certificates are assumed. This
1018 can be easily extended to work with openpgp keys as well. */
1019 if (fn_gnutls_certificate_type_get (state) == GNUTLS_CRT_X509)
1020 {
1021 ret = fn_gnutls_x509_crt_init (&gnutls_verify_cert);
1022
1023 if (ret < GNUTLS_E_SUCCESS)
1024 return gnutls_make_error (ret);
1025
1026 gnutls_verify_cert_list =
1027 fn_gnutls_certificate_get_peers (state, &gnutls_verify_cert_list_size);
1028
1029 if (NULL == gnutls_verify_cert_list)
1030 {
1031 error ("No x509 certificate was found!\n");
1032 }
1033
1034 /* We only check the first certificate in the given chain. */
1035 ret = fn_gnutls_x509_crt_import (gnutls_verify_cert,
1036 &gnutls_verify_cert_list[0],
1037 GNUTLS_X509_FMT_DER);
1038
1039 if (ret < GNUTLS_E_SUCCESS)
1040 {
1041 fn_gnutls_x509_crt_deinit (gnutls_verify_cert);
1042 return gnutls_make_error (ret);
1043 }
1044
1045 if (!fn_gnutls_x509_crt_check_hostname (gnutls_verify_cert, c_hostname))
1046 {
1047 if (NILP (verify_hostname_error))
1048 {
1049 GNUTLS_LOG2 (1, max_log_level, "x509 certificate does not match:",
1050 c_hostname);
1051 }
1052 else
1053 {
1054 fn_gnutls_x509_crt_deinit (gnutls_verify_cert);
1055 error ("The x509 certificate does not match \"%s\"",
1056 c_hostname);
1057 }
1058 }
1059
1060 fn_gnutls_x509_crt_deinit (gnutls_verify_cert);
1061 }
1062
1063 return gnutls_make_error (ret);
1064 }
1065
1066 DEFUN ("gnutls-bye", Fgnutls_bye,
1067 Sgnutls_bye, 2, 2, 0,
1068 doc: /* Terminate current GnuTLS connection for process PROC.
1069 The connection should have been initiated using `gnutls-handshake'.
1070
1071 If CONT is not nil the TLS connection gets terminated and further
1072 receives and sends will be disallowed. If the return value is zero you
1073 may continue using the connection. If CONT is nil, GnuTLS actually
1074 sends an alert containing a close request and waits for the peer to
1075 reply with the same message. In order to reuse the connection you
1076 should wait for an EOF from the peer.
1077
1078 This function may also return `gnutls-e-again', or
1079 `gnutls-e-interrupted'. */)
1080 (Lisp_Object proc, Lisp_Object cont)
1081 {
1082 gnutls_session_t state;
1083 int ret;
1084
1085 CHECK_PROCESS (proc);
1086
1087 state = XPROCESS (proc)->gnutls_state;
1088
1089 ret = fn_gnutls_bye (state,
1090 NILP (cont) ? GNUTLS_SHUT_RDWR : GNUTLS_SHUT_WR);
1091
1092 return gnutls_make_error (ret);
1093 }
1094
1095 void
1096 syms_of_gnutls (void)
1097 {
1098 gnutls_global_initialized = 0;
1099
1100 DEFSYM (Qgnutls_dll, "gnutls");
1101 DEFSYM (Qgnutls_log_level, "gnutls-log-level");
1102 DEFSYM (Qgnutls_code, "gnutls-code");
1103 DEFSYM (Qgnutls_anon, "gnutls-anon");
1104 DEFSYM (Qgnutls_x509pki, "gnutls-x509pki");
1105 DEFSYM (Qgnutls_bootprop_hostname, ":hostname");
1106 DEFSYM (Qgnutls_bootprop_priority, ":priority");
1107 DEFSYM (Qgnutls_bootprop_trustfiles, ":trustfiles");
1108 DEFSYM (Qgnutls_bootprop_keylist, ":keylist");
1109 DEFSYM (Qgnutls_bootprop_crlfiles, ":crlfiles");
1110 DEFSYM (Qgnutls_bootprop_callbacks, ":callbacks");
1111 DEFSYM (Qgnutls_bootprop_callbacks_verify, "verify");
1112 DEFSYM (Qgnutls_bootprop_loglevel, ":loglevel");
1113 DEFSYM (Qgnutls_bootprop_verify_flags, ":verify-flags");
1114 DEFSYM (Qgnutls_bootprop_verify_hostname_error, ":verify-hostname-error");
1115
1116 DEFSYM (Qgnutls_e_interrupted, "gnutls-e-interrupted");
1117 Fput (Qgnutls_e_interrupted, Qgnutls_code,
1118 make_number (GNUTLS_E_INTERRUPTED));
1119
1120 DEFSYM (Qgnutls_e_again, "gnutls-e-again");
1121 Fput (Qgnutls_e_again, Qgnutls_code,
1122 make_number (GNUTLS_E_AGAIN));
1123
1124 DEFSYM (Qgnutls_e_invalid_session, "gnutls-e-invalid-session");
1125 Fput (Qgnutls_e_invalid_session, Qgnutls_code,
1126 make_number (GNUTLS_E_INVALID_SESSION));
1127
1128 DEFSYM (Qgnutls_e_not_ready_for_handshake, "gnutls-e-not-ready-for-handshake");
1129 Fput (Qgnutls_e_not_ready_for_handshake, Qgnutls_code,
1130 make_number (GNUTLS_E_APPLICATION_ERROR_MIN));
1131
1132 defsubr (&Sgnutls_get_initstage);
1133 defsubr (&Sgnutls_errorp);
1134 defsubr (&Sgnutls_error_fatalp);
1135 defsubr (&Sgnutls_error_string);
1136 defsubr (&Sgnutls_boot);
1137 defsubr (&Sgnutls_deinit);
1138 defsubr (&Sgnutls_bye);
1139 defsubr (&Sgnutls_available_p);
1140 }
1141
1142 #endif /* HAVE_GNUTLS */