Merge branch 'cn/commit-amend-doc'
[git] / contrib / credential / gnome-keyring / git-credential-gnome-keyring.c
1 /*
2  * Copyright (C) 2011 John Szakmeister <john@szakmeister.net>
3  *               2012 Philipp A. Hartmann <pah@qo.cx>
4  *
5  *  This program is free software; you can redistribute it and/or modify
6  *  it under the terms of the GNU General Public License as published by
7  *  the Free Software Foundation; either version 2 of the License, or
8  *  (at your option) any later version.
9  *
10  *  This program is distributed in the hope that it will be useful,
11  *  but WITHOUT ANY WARRANTY; without even the implied warranty of
12  *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
13  *  GNU General Public License for more details.
14  *
15  *  You should have received a copy of the GNU General Public License
16  *  along with this program; if not, write to the Free Software
17  *  Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
18  */
19
20 /*
21  * Credits:
22  * - GNOME Keyring API handling originally written by John Szakmeister
23  * - ported to credential helper API by Philipp A. Hartmann
24  */
25
26 #include <stdio.h>
27 #include <string.h>
28 #include <stdarg.h>
29 #include <stdlib.h>
30 #include <errno.h>
31 #include <gnome-keyring.h>
32
33 /*
34  * This credential struct and API is simplified from git's credential.{h,c}
35  */
36 struct credential
37 {
38         char          *protocol;
39         char          *host;
40         unsigned short port;
41         char          *path;
42         char          *username;
43         char          *password;
44 };
45
46 #define CREDENTIAL_INIT \
47   { NULL,NULL,0,NULL,NULL,NULL }
48
49 void credential_init(struct credential *c);
50 void credential_clear(struct credential *c);
51 int  credential_read(struct credential *c);
52 void credential_write(const struct credential *c);
53
54 typedef int (*credential_op_cb)(struct credential*);
55
56 struct credential_operation
57 {
58         char             *name;
59         credential_op_cb op;
60 };
61
62 #define CREDENTIAL_OP_END \
63   { NULL,NULL }
64
65 /*
66  * Table with operation callbacks is defined in concrete
67  * credential helper implementation and contains entries
68  * like { "get", function_to_get_credential } terminated
69  * by CREDENTIAL_OP_END.
70  */
71 struct credential_operation const credential_helper_ops[];
72
73 /* ---------------- common helper functions ----------------- */
74
75 static inline void free_password(char *password)
76 {
77         char *c = password;
78         if (!password)
79                 return;
80
81         while (*c) *c++ = '\0';
82         free(password);
83 }
84
85 static inline void warning(const char *fmt, ...)
86 {
87         va_list ap;
88
89         va_start(ap, fmt);
90         fprintf(stderr, "warning: ");
91         vfprintf(stderr, fmt, ap);
92         fprintf(stderr, "\n" );
93         va_end(ap);
94 }
95
96 static inline void error(const char *fmt, ...)
97 {
98         va_list ap;
99
100         va_start(ap, fmt);
101         fprintf(stderr, "error: ");
102         vfprintf(stderr, fmt, ap);
103         fprintf(stderr, "\n" );
104         va_end(ap);
105 }
106
107 static inline void die(const char *fmt, ...)
108 {
109         va_list ap;
110
111         va_start(ap,fmt);
112         error(fmt, ap);
113         va_end(ap);
114         exit(EXIT_FAILURE);
115 }
116
117 static inline void die_errno(int err)
118 {
119         error("%s", strerror(err));
120         exit(EXIT_FAILURE);
121 }
122
123 static inline char *xstrdup(const char *str)
124 {
125         char *ret = strdup(str);
126         if (!ret)
127                 die_errno(errno);
128
129         return ret;
130 }
131
132 /* ----------------- GNOME Keyring functions ----------------- */
133
134 /* create a special keyring option string, if path is given */
135 static char* keyring_object(struct credential *c)
136 {
137         char* object = NULL;
138
139         if (!c->path)
140                 return object;
141
142         object = (char*) malloc(strlen(c->host)+strlen(c->path)+8);
143         if(!object)
144                 die_errno(errno);
145
146         if(c->port)
147                 sprintf(object,"%s:%hd/%s",c->host,c->port,c->path);
148         else
149                 sprintf(object,"%s/%s",c->host,c->path);
150
151         return object;
152 }
153
154 int keyring_get(struct credential *c)
155 {
156         char* object = NULL;
157         GList *entries;
158         GnomeKeyringNetworkPasswordData *password_data;
159         GnomeKeyringResult result;
160
161         if (!c->protocol || !(c->host || c->path))
162                 return EXIT_FAILURE;
163
164         object = keyring_object(c);
165
166         result = gnome_keyring_find_network_password_sync(
167                                 c->username,
168                                 NULL /* domain */,
169                                 c->host,
170                                 object,
171                                 c->protocol,
172                                 NULL /* authtype */,
173                                 c->port,
174                                 &entries);
175
176         free(object);
177
178         if (result == GNOME_KEYRING_RESULT_NO_MATCH)
179                 return EXIT_SUCCESS;
180
181         if (result == GNOME_KEYRING_RESULT_CANCELLED)
182                 return EXIT_SUCCESS;
183
184         if (result != GNOME_KEYRING_RESULT_OK) {
185                 error("%s",gnome_keyring_result_to_message(result));
186                 return EXIT_FAILURE;
187         }
188
189         /* pick the first one from the list */
190         password_data = (GnomeKeyringNetworkPasswordData *) entries->data;
191
192         free_password(c->password);
193         c->password = xstrdup(password_data->password);
194
195         if (!c->username)
196                 c->username = xstrdup(password_data->user);
197
198         gnome_keyring_network_password_list_free(entries);
199
200         return EXIT_SUCCESS;
201 }
202
203
204 int keyring_store(struct credential *c)
205 {
206         guint32 item_id;
207         char  *object = NULL;
208
209         /*
210          * Sanity check that what we are storing is actually sensible.
211          * In particular, we can't make a URL without a protocol field.
212          * Without either a host or pathname (depending on the scheme),
213          * we have no primary key. And without a username and password,
214          * we are not actually storing a credential.
215          */
216         if (!c->protocol || !(c->host || c->path) ||
217             !c->username || !c->password)
218                 return EXIT_FAILURE;
219
220         object = keyring_object(c);
221
222         gnome_keyring_set_network_password_sync(
223                                 GNOME_KEYRING_DEFAULT,
224                                 c->username,
225                                 NULL /* domain */,
226                                 c->host,
227                                 object,
228                                 c->protocol,
229                                 NULL /* authtype */,
230                                 c->port,
231                                 c->password,
232                                 &item_id);
233
234         free(object);
235         return EXIT_SUCCESS;
236 }
237
238 int keyring_erase(struct credential *c)
239 {
240         char  *object = NULL;
241         GList *entries;
242         GnomeKeyringNetworkPasswordData *password_data;
243         GnomeKeyringResult result;
244
245         /*
246          * Sanity check that we actually have something to match
247          * against. The input we get is a restrictive pattern,
248          * so technically a blank credential means "erase everything".
249          * But it is too easy to accidentally send this, since it is equivalent
250          * to empty input. So explicitly disallow it, and require that the
251          * pattern have some actual content to match.
252          */
253         if (!c->protocol && !c->host && !c->path && !c->username)
254                 return EXIT_FAILURE;
255
256         object = keyring_object(c);
257
258         result = gnome_keyring_find_network_password_sync(
259                                 c->username,
260                                 NULL /* domain */,
261                                 c->host,
262                                 object,
263                                 c->protocol,
264                                 NULL /* authtype */,
265                                 c->port,
266                                 &entries);
267
268         free(object);
269
270         if (result == GNOME_KEYRING_RESULT_NO_MATCH)
271                 return EXIT_SUCCESS;
272
273         if (result == GNOME_KEYRING_RESULT_CANCELLED)
274                 return EXIT_SUCCESS;
275
276         if (result != GNOME_KEYRING_RESULT_OK)
277         {
278                 error("%s",gnome_keyring_result_to_message(result));
279                 return EXIT_FAILURE;
280         }
281
282         /* pick the first one from the list (delete all matches?) */
283         password_data = (GnomeKeyringNetworkPasswordData *) entries->data;
284
285         result = gnome_keyring_item_delete_sync(
286                 password_data->keyring, password_data->item_id);
287
288         gnome_keyring_network_password_list_free(entries);
289
290         if (result != GNOME_KEYRING_RESULT_OK)
291         {
292                 error("%s",gnome_keyring_result_to_message(result));
293                 return EXIT_FAILURE;
294         }
295
296         return EXIT_SUCCESS;
297 }
298
299 /*
300  * Table with helper operation callbacks, used by generic
301  * credential helper main function.
302  */
303 struct credential_operation const credential_helper_ops[] =
304 {
305         { "get",   keyring_get   },
306         { "store", keyring_store },
307         { "erase", keyring_erase },
308         CREDENTIAL_OP_END
309 };
310
311 /* ------------------ credential functions ------------------ */
312
313 void credential_init(struct credential *c)
314 {
315         memset(c, 0, sizeof(*c));
316 }
317
318 void credential_clear(struct credential *c)
319 {
320         free(c->protocol);
321         free(c->host);
322         free(c->path);
323         free(c->username);
324         free_password(c->password);
325
326         credential_init(c);
327 }
328
329 int credential_read(struct credential *c)
330 {
331         char    buf[1024];
332         ssize_t line_len = 0;
333         char   *key      = buf;
334         char   *value;
335
336         while (fgets(buf, sizeof(buf), stdin))
337         {
338                 line_len = strlen(buf);
339
340                 if(buf[line_len-1]=='\n')
341                         buf[--line_len]='\0';
342
343                 if(!line_len)
344                         break;
345
346                 value = strchr(buf,'=');
347                 if(!value) {
348                         warning("invalid credential line: %s", key);
349                         return -1;
350                 }
351                 *value++ = '\0';
352
353                 if (!strcmp(key, "protocol")) {
354                         free(c->protocol);
355                         c->protocol = xstrdup(value);
356                 } else if (!strcmp(key, "host")) {
357                         free(c->host);
358                         c->host = xstrdup(value);
359                         value = strrchr(c->host,':');
360                         if (value) {
361                                 *value++ = '\0';
362                                 c->port = atoi(value);
363                         }
364                 } else if (!strcmp(key, "path")) {
365                         free(c->path);
366                         c->path = xstrdup(value);
367                 } else if (!strcmp(key, "username")) {
368                         free(c->username);
369                         c->username = xstrdup(value);
370                 } else if (!strcmp(key, "password")) {
371                         free_password(c->password);
372                         c->password = xstrdup(value);
373                         while (*value) *value++ = '\0';
374                 }
375                 /*
376                  * Ignore other lines; we don't know what they mean, but
377                  * this future-proofs us when later versions of git do
378                  * learn new lines, and the helpers are updated to match.
379                  */
380         }
381         return 0;
382 }
383
384 void credential_write_item(FILE *fp, const char *key, const char *value)
385 {
386         if (!value)
387                 return;
388         fprintf(fp, "%s=%s\n", key, value);
389 }
390
391 void credential_write(const struct credential *c)
392 {
393         /* only write username/password, if set */
394         credential_write_item(stdout, "username", c->username);
395         credential_write_item(stdout, "password", c->password);
396 }
397
398 static void usage(const char *name)
399 {
400         struct credential_operation const *try_op = credential_helper_ops;
401         const char *basename = strrchr(name,'/');
402
403         basename = (basename) ? basename + 1 : name;
404         fprintf(stderr, "usage: %s <", basename);
405         while(try_op->name) {
406                 fprintf(stderr,"%s",(try_op++)->name);
407                 if(try_op->name)
408                         fprintf(stderr,"%s","|");
409         }
410         fprintf(stderr,"%s",">\n");
411 }
412
413 int main(int argc, char *argv[])
414 {
415         int ret = EXIT_SUCCESS;
416
417         struct credential_operation const *try_op = credential_helper_ops;
418         struct credential                  cred   = CREDENTIAL_INIT;
419
420         if (!argv[1]) {
421                 usage(argv[0]);
422                 goto out;
423         }
424
425         /* lookup operation callback */
426         while(try_op->name && strcmp(argv[1], try_op->name))
427                 try_op++;
428
429         /* unsupported operation given -- ignore silently */
430         if(!try_op->name || !try_op->op)
431                 goto out;
432
433         ret = credential_read(&cred);
434         if(ret)
435                 goto out;
436
437         /* perform credential operation */
438         ret = (*try_op->op)(&cred);
439
440         credential_write(&cred);
441
442 out:
443         credential_clear(&cred);
444         return ret;
445 }