1 /*
2 * Copyright (C) 2011 John Szakmeister <john@szakmeister.net>
3 * 2012 Philipp A. Hartmann <pah@qo.cx>
4 * 2016 Mantas Mikulėnas <grawity@gmail.com>
5 *
6 * This program 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 2 of the License, or
9 * (at your option) any later version.
10 *
11 * This program 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 this program; if not, see <http://www.gnu.org/licenses/>.
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 <stdlib.h>
29 #include <glib.h>
30 #include <libsecret/secret.h>
31
32 /*
33 * This credential struct and API is simplified from git's credential.{h,c}
34 */
35 struct credential {
36 char *protocol;
37 char *host;
38 unsigned short port;
39 char *path;
40 char *username;
41 char *password;
42 };
43
44 #define CREDENTIAL_INIT { 0 }
45
46 typedef int (*credential_op_cb)(struct credential *);
47
48 struct credential_operation {
49 char *name;
50 credential_op_cb op;
51 };
52
53 #define CREDENTIAL_OP_END { NULL, NULL }
54
55 /* ----------------- Secret Service functions ----------------- */
56
make_label(struct credential * c)57 static char *make_label(struct credential *c)
58 {
59 if (c->port)
60 return g_strdup_printf("Git: %s://%s:%hu/%s",
61 c->protocol, c->host, c->port, c->path ? c->path : "");
62 else
63 return g_strdup_printf("Git: %s://%s/%s",
64 c->protocol, c->host, c->path ? c->path : "");
65 }
66
make_attr_list(struct credential * c)67 static GHashTable *make_attr_list(struct credential *c)
68 {
69 GHashTable *al = g_hash_table_new_full(g_str_hash, g_str_equal, NULL, g_free);
70
71 if (c->username)
72 g_hash_table_insert(al, "user", g_strdup(c->username));
73 if (c->protocol)
74 g_hash_table_insert(al, "protocol", g_strdup(c->protocol));
75 if (c->host)
76 g_hash_table_insert(al, "server", g_strdup(c->host));
77 if (c->port)
78 g_hash_table_insert(al, "port", g_strdup_printf("%hu", c->port));
79 if (c->path)
80 g_hash_table_insert(al, "object", g_strdup(c->path));
81
82 return al;
83 }
84
keyring_get(struct credential * c)85 static int keyring_get(struct credential *c)
86 {
87 SecretService *service = NULL;
88 GHashTable *attributes = NULL;
89 GError *error = NULL;
90 GList *items = NULL;
91
92 if (!c->protocol || !(c->host || c->path))
93 return EXIT_FAILURE;
94
95 service = secret_service_get_sync(0, NULL, &error);
96 if (error != NULL) {
97 g_critical("could not connect to Secret Service: %s", error->message);
98 g_error_free(error);
99 return EXIT_FAILURE;
100 }
101
102 attributes = make_attr_list(c);
103 items = secret_service_search_sync(service,
104 SECRET_SCHEMA_COMPAT_NETWORK,
105 attributes,
106 SECRET_SEARCH_LOAD_SECRETS | SECRET_SEARCH_UNLOCK,
107 NULL,
108 &error);
109 g_hash_table_unref(attributes);
110 if (error != NULL) {
111 g_critical("lookup failed: %s", error->message);
112 g_error_free(error);
113 return EXIT_FAILURE;
114 }
115
116 if (items != NULL) {
117 SecretItem *item;
118 SecretValue *secret;
119 const char *s;
120
121 item = items->data;
122 secret = secret_item_get_secret(item);
123 attributes = secret_item_get_attributes(item);
124
125 s = g_hash_table_lookup(attributes, "user");
126 if (s) {
127 g_free(c->username);
128 c->username = g_strdup(s);
129 }
130
131 s = secret_value_get_text(secret);
132 if (s) {
133 g_free(c->password);
134 c->password = g_strdup(s);
135 }
136
137 g_hash_table_unref(attributes);
138 secret_value_unref(secret);
139 g_list_free_full(items, g_object_unref);
140 }
141
142 return EXIT_SUCCESS;
143 }
144
145
keyring_store(struct credential * c)146 static int keyring_store(struct credential *c)
147 {
148 char *label = NULL;
149 GHashTable *attributes = NULL;
150 GError *error = NULL;
151
152 /*
153 * Sanity check that what we are storing is actually sensible.
154 * In particular, we can't make a URL without a protocol field.
155 * Without either a host or pathname (depending on the scheme),
156 * we have no primary key. And without a username and password,
157 * we are not actually storing a credential.
158 */
159 if (!c->protocol || !(c->host || c->path) ||
160 !c->username || !c->password)
161 return EXIT_FAILURE;
162
163 label = make_label(c);
164 attributes = make_attr_list(c);
165 secret_password_storev_sync(SECRET_SCHEMA_COMPAT_NETWORK,
166 attributes,
167 NULL,
168 label,
169 c->password,
170 NULL,
171 &error);
172 g_free(label);
173 g_hash_table_unref(attributes);
174
175 if (error != NULL) {
176 g_critical("store failed: %s", error->message);
177 g_error_free(error);
178 return EXIT_FAILURE;
179 }
180
181 return EXIT_SUCCESS;
182 }
183
keyring_erase(struct credential * c)184 static int keyring_erase(struct credential *c)
185 {
186 GHashTable *attributes = NULL;
187 GError *error = NULL;
188
189 /*
190 * Sanity check that we actually have something to match
191 * against. The input we get is a restrictive pattern,
192 * so technically a blank credential means "erase everything".
193 * But it is too easy to accidentally send this, since it is equivalent
194 * to empty input. So explicitly disallow it, and require that the
195 * pattern have some actual content to match.
196 */
197 if (!c->protocol && !c->host && !c->path && !c->username)
198 return EXIT_FAILURE;
199
200 attributes = make_attr_list(c);
201 secret_password_clearv_sync(SECRET_SCHEMA_COMPAT_NETWORK,
202 attributes,
203 NULL,
204 &error);
205 g_hash_table_unref(attributes);
206
207 if (error != NULL) {
208 g_critical("erase failed: %s", error->message);
209 g_error_free(error);
210 return EXIT_FAILURE;
211 }
212
213 return EXIT_SUCCESS;
214 }
215
216 /*
217 * Table with helper operation callbacks, used by generic
218 * credential helper main function.
219 */
220 static struct credential_operation const credential_helper_ops[] = {
221 { "get", keyring_get },
222 { "store", keyring_store },
223 { "erase", keyring_erase },
224 CREDENTIAL_OP_END
225 };
226
227 /* ------------------ credential functions ------------------ */
228
credential_init(struct credential * c)229 static void credential_init(struct credential *c)
230 {
231 memset(c, 0, sizeof(*c));
232 }
233
credential_clear(struct credential * c)234 static void credential_clear(struct credential *c)
235 {
236 g_free(c->protocol);
237 g_free(c->host);
238 g_free(c->path);
239 g_free(c->username);
240 g_free(c->password);
241
242 credential_init(c);
243 }
244
credential_read(struct credential * c)245 static int credential_read(struct credential *c)
246 {
247 char *buf;
248 size_t line_len;
249 char *key;
250 char *value;
251
252 key = buf = g_malloc(1024);
253
254 while (fgets(buf, 1024, stdin)) {
255 line_len = strlen(buf);
256
257 if (line_len && buf[line_len-1] == '\n')
258 buf[--line_len] = '\0';
259
260 if (!line_len)
261 break;
262
263 value = strchr(buf, '=');
264 if (!value) {
265 g_warning("invalid credential line: %s", key);
266 g_free(buf);
267 return -1;
268 }
269 *value++ = '\0';
270
271 if (!strcmp(key, "protocol")) {
272 g_free(c->protocol);
273 c->protocol = g_strdup(value);
274 } else if (!strcmp(key, "host")) {
275 g_free(c->host);
276 c->host = g_strdup(value);
277 value = strrchr(c->host, ':');
278 if (value) {
279 *value++ = '\0';
280 c->port = atoi(value);
281 }
282 } else if (!strcmp(key, "path")) {
283 g_free(c->path);
284 c->path = g_strdup(value);
285 } else if (!strcmp(key, "username")) {
286 g_free(c->username);
287 c->username = g_strdup(value);
288 } else if (!strcmp(key, "password")) {
289 g_free(c->password);
290 c->password = g_strdup(value);
291 while (*value)
292 *value++ = '\0';
293 }
294 /*
295 * Ignore other lines; we don't know what they mean, but
296 * this future-proofs us when later versions of git do
297 * learn new lines, and the helpers are updated to match.
298 */
299 }
300
301 g_free(buf);
302
303 return 0;
304 }
305
credential_write_item(FILE * fp,const char * key,const char * value)306 static void credential_write_item(FILE *fp, const char *key, const char *value)
307 {
308 if (!value)
309 return;
310 fprintf(fp, "%s=%s\n", key, value);
311 }
312
credential_write(const struct credential * c)313 static void credential_write(const struct credential *c)
314 {
315 /* only write username/password, if set */
316 credential_write_item(stdout, "username", c->username);
317 credential_write_item(stdout, "password", c->password);
318 }
319
usage(const char * name)320 static void usage(const char *name)
321 {
322 struct credential_operation const *try_op = credential_helper_ops;
323 const char *basename = strrchr(name, '/');
324
325 basename = (basename) ? basename + 1 : name;
326 fprintf(stderr, "usage: %s <", basename);
327 while (try_op->name) {
328 fprintf(stderr, "%s", (try_op++)->name);
329 if (try_op->name)
330 fprintf(stderr, "%s", "|");
331 }
332 fprintf(stderr, "%s", ">\n");
333 }
334
main(int argc,char * argv[])335 int main(int argc, char *argv[])
336 {
337 int ret = EXIT_SUCCESS;
338
339 struct credential_operation const *try_op = credential_helper_ops;
340 struct credential cred = CREDENTIAL_INIT;
341
342 if (!argv[1]) {
343 usage(argv[0]);
344 exit(EXIT_FAILURE);
345 }
346
347 g_set_application_name("Git Credential Helper");
348
349 /* lookup operation callback */
350 while (try_op->name && strcmp(argv[1], try_op->name))
351 try_op++;
352
353 /* unsupported operation given -- ignore silently */
354 if (!try_op->name || !try_op->op)
355 goto out;
356
357 ret = credential_read(&cred);
358 if (ret)
359 goto out;
360
361 /* perform credential operation */
362 ret = (*try_op->op)(&cred);
363
364 credential_write(&cred);
365
366 out:
367 credential_clear(&cred);
368 return ret;
369 }
370