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