Sync with 2.17.2
[git] / credential.c
1 #include "cache.h"
2 #include "config.h"
3 #include "credential.h"
4 #include "string-list.h"
5 #include "run-command.h"
6 #include "url.h"
7 #include "prompt.h"
8 #include "sigchain.h"
9
10 void credential_init(struct credential *c)
11 {
12         memset(c, 0, sizeof(*c));
13         c->helpers.strdup_strings = 1;
14 }
15
16 void credential_clear(struct credential *c)
17 {
18         free(c->protocol);
19         free(c->host);
20         free(c->path);
21         free(c->username);
22         free(c->password);
23         string_list_clear(&c->helpers, 0);
24
25         credential_init(c);
26 }
27
28 int credential_match(const struct credential *want,
29                      const struct credential *have)
30 {
31 #define CHECK(x) (!want->x || (have->x && !strcmp(want->x, have->x)))
32         return CHECK(protocol) &&
33                CHECK(host) &&
34                CHECK(path) &&
35                CHECK(username);
36 #undef CHECK
37 }
38
39 static int credential_config_callback(const char *var, const char *value,
40                                       void *data)
41 {
42         struct credential *c = data;
43         const char *key, *dot;
44
45         if (!skip_prefix(var, "credential.", &key))
46                 return 0;
47
48         if (!value)
49                 return config_error_nonbool(var);
50
51         dot = strrchr(key, '.');
52         if (dot) {
53                 struct credential want = CREDENTIAL_INIT;
54                 char *url = xmemdupz(key, dot - key);
55                 int matched;
56
57                 credential_from_url(&want, url);
58                 matched = credential_match(&want, c);
59
60                 credential_clear(&want);
61                 free(url);
62
63                 if (!matched)
64                         return 0;
65                 key = dot + 1;
66         }
67
68         if (!strcmp(key, "helper")) {
69                 if (*value)
70                         string_list_append(&c->helpers, value);
71                 else
72                         string_list_clear(&c->helpers, 0);
73         } else if (!strcmp(key, "username")) {
74                 if (!c->username)
75                         c->username = xstrdup(value);
76         }
77         else if (!strcmp(key, "usehttppath"))
78                 c->use_http_path = git_config_bool(var, value);
79
80         return 0;
81 }
82
83 static int proto_is_http(const char *s)
84 {
85         if (!s)
86                 return 0;
87         return !strcmp(s, "https") || !strcmp(s, "http");
88 }
89
90 static void credential_apply_config(struct credential *c)
91 {
92         if (c->configured)
93                 return;
94         git_config(credential_config_callback, c);
95         c->configured = 1;
96
97         if (!c->use_http_path && proto_is_http(c->protocol)) {
98                 FREE_AND_NULL(c->path);
99         }
100 }
101
102 static void credential_describe(struct credential *c, struct strbuf *out)
103 {
104         if (!c->protocol)
105                 return;
106         strbuf_addf(out, "%s://", c->protocol);
107         if (c->username && *c->username)
108                 strbuf_addf(out, "%s@", c->username);
109         if (c->host)
110                 strbuf_addstr(out, c->host);
111         if (c->path)
112                 strbuf_addf(out, "/%s", c->path);
113 }
114
115 static char *credential_ask_one(const char *what, struct credential *c,
116                                 int flags)
117 {
118         struct strbuf desc = STRBUF_INIT;
119         struct strbuf prompt = STRBUF_INIT;
120         char *r;
121
122         credential_describe(c, &desc);
123         if (desc.len)
124                 strbuf_addf(&prompt, "%s for '%s': ", what, desc.buf);
125         else
126                 strbuf_addf(&prompt, "%s: ", what);
127
128         r = git_prompt(prompt.buf, flags);
129
130         strbuf_release(&desc);
131         strbuf_release(&prompt);
132         return xstrdup(r);
133 }
134
135 static void credential_getpass(struct credential *c)
136 {
137         if (!c->username)
138                 c->username = credential_ask_one("Username", c,
139                                                  PROMPT_ASKPASS|PROMPT_ECHO);
140         if (!c->password)
141                 c->password = credential_ask_one("Password", c,
142                                                  PROMPT_ASKPASS);
143 }
144
145 int credential_read(struct credential *c, FILE *fp)
146 {
147         struct strbuf line = STRBUF_INIT;
148
149         while (strbuf_getline_lf(&line, fp) != EOF) {
150                 char *key = line.buf;
151                 char *value = strchr(key, '=');
152
153                 if (!line.len)
154                         break;
155
156                 if (!value) {
157                         warning("invalid credential line: %s", key);
158                         strbuf_release(&line);
159                         return -1;
160                 }
161                 *value++ = '\0';
162
163                 if (!strcmp(key, "username")) {
164                         free(c->username);
165                         c->username = xstrdup(value);
166                 } else if (!strcmp(key, "password")) {
167                         free(c->password);
168                         c->password = xstrdup(value);
169                 } else if (!strcmp(key, "protocol")) {
170                         free(c->protocol);
171                         c->protocol = xstrdup(value);
172                 } else if (!strcmp(key, "host")) {
173                         free(c->host);
174                         c->host = xstrdup(value);
175                 } else if (!strcmp(key, "path")) {
176                         free(c->path);
177                         c->path = xstrdup(value);
178                 } else if (!strcmp(key, "url")) {
179                         credential_from_url(c, value);
180                 } else if (!strcmp(key, "quit")) {
181                         c->quit = !!git_config_bool("quit", value);
182                 }
183                 /*
184                  * Ignore other lines; we don't know what they mean, but
185                  * this future-proofs us when later versions of git do
186                  * learn new lines, and the helpers are updated to match.
187                  */
188         }
189
190         strbuf_release(&line);
191         return 0;
192 }
193
194 static void credential_write_item(FILE *fp, const char *key, const char *value)
195 {
196         if (!value)
197                 return;
198         fprintf(fp, "%s=%s\n", key, value);
199 }
200
201 void credential_write(const struct credential *c, FILE *fp)
202 {
203         credential_write_item(fp, "protocol", c->protocol);
204         credential_write_item(fp, "host", c->host);
205         credential_write_item(fp, "path", c->path);
206         credential_write_item(fp, "username", c->username);
207         credential_write_item(fp, "password", c->password);
208 }
209
210 static int run_credential_helper(struct credential *c,
211                                  const char *cmd,
212                                  int want_output)
213 {
214         struct child_process helper = CHILD_PROCESS_INIT;
215         const char *argv[] = { NULL, NULL };
216         FILE *fp;
217
218         argv[0] = cmd;
219         helper.argv = argv;
220         helper.use_shell = 1;
221         helper.in = -1;
222         if (want_output)
223                 helper.out = -1;
224         else
225                 helper.no_stdout = 1;
226
227         if (start_command(&helper) < 0)
228                 return -1;
229
230         fp = xfdopen(helper.in, "w");
231         sigchain_push(SIGPIPE, SIG_IGN);
232         credential_write(c, fp);
233         fclose(fp);
234         sigchain_pop(SIGPIPE);
235
236         if (want_output) {
237                 int r;
238                 fp = xfdopen(helper.out, "r");
239                 r = credential_read(c, fp);
240                 fclose(fp);
241                 if (r < 0) {
242                         finish_command(&helper);
243                         return -1;
244                 }
245         }
246
247         if (finish_command(&helper))
248                 return -1;
249         return 0;
250 }
251
252 static int credential_do(struct credential *c, const char *helper,
253                          const char *operation)
254 {
255         struct strbuf cmd = STRBUF_INIT;
256         int r;
257
258         if (helper[0] == '!')
259                 strbuf_addstr(&cmd, helper + 1);
260         else if (is_absolute_path(helper))
261                 strbuf_addstr(&cmd, helper);
262         else
263                 strbuf_addf(&cmd, "git credential-%s", helper);
264
265         strbuf_addf(&cmd, " %s", operation);
266         r = run_credential_helper(c, cmd.buf, !strcmp(operation, "get"));
267
268         strbuf_release(&cmd);
269         return r;
270 }
271
272 void credential_fill(struct credential *c)
273 {
274         int i;
275
276         if (c->username && c->password)
277                 return;
278
279         credential_apply_config(c);
280
281         for (i = 0; i < c->helpers.nr; i++) {
282                 credential_do(c, c->helpers.items[i].string, "get");
283                 if (c->username && c->password)
284                         return;
285                 if (c->quit)
286                         die("credential helper '%s' told us to quit",
287                             c->helpers.items[i].string);
288         }
289
290         credential_getpass(c);
291         if (!c->username && !c->password)
292                 die("unable to get password from user");
293 }
294
295 void credential_approve(struct credential *c)
296 {
297         int i;
298
299         if (c->approved)
300                 return;
301         if (!c->username || !c->password)
302                 return;
303
304         credential_apply_config(c);
305
306         for (i = 0; i < c->helpers.nr; i++)
307                 credential_do(c, c->helpers.items[i].string, "store");
308         c->approved = 1;
309 }
310
311 void credential_reject(struct credential *c)
312 {
313         int i;
314
315         credential_apply_config(c);
316
317         for (i = 0; i < c->helpers.nr; i++)
318                 credential_do(c, c->helpers.items[i].string, "erase");
319
320         FREE_AND_NULL(c->username);
321         FREE_AND_NULL(c->password);
322         c->approved = 0;
323 }
324
325 void credential_from_url(struct credential *c, const char *url)
326 {
327         const char *at, *colon, *cp, *slash, *host, *proto_end;
328
329         credential_clear(c);
330
331         /*
332          * Match one of:
333          *   (1) proto://<host>/...
334          *   (2) proto://<user>@<host>/...
335          *   (3) proto://<user>:<pass>@<host>/...
336          */
337         proto_end = strstr(url, "://");
338         if (!proto_end)
339                 return;
340         cp = proto_end + 3;
341         at = strchr(cp, '@');
342         colon = strchr(cp, ':');
343         slash = strchrnul(cp, '/');
344
345         if (!at || slash <= at) {
346                 /* Case (1) */
347                 host = cp;
348         }
349         else if (!colon || at <= colon) {
350                 /* Case (2) */
351                 c->username = url_decode_mem(cp, at - cp);
352                 host = at + 1;
353         } else {
354                 /* Case (3) */
355                 c->username = url_decode_mem(cp, colon - cp);
356                 c->password = url_decode_mem(colon + 1, at - (colon + 1));
357                 host = at + 1;
358         }
359
360         if (proto_end - url > 0)
361                 c->protocol = xmemdupz(url, proto_end - url);
362         if (slash - host > 0)
363                 c->host = url_decode_mem(host, slash - host);
364         /* Trim leading and trailing slashes from path */
365         while (*slash == '/')
366                 slash++;
367         if (*slash) {
368                 char *p;
369                 c->path = url_decode(slash);
370                 p = c->path + strlen(c->path) - 1;
371                 while (p > c->path && *p == '/')
372                         *p-- = '\0';
373         }
374 }