git.oblomov.eu Git - git/blob - 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         if (strchr(value, '\n'))
 199                 die("credential value for %s contains newline", key);
 200         fprintf(fp, "%s=%s\n", key, value);
 201 }
 202
 203 void credential_write(const struct credential *c, FILE *fp)
 204 {
 205         credential_write_item(fp, "protocol", c->protocol);
 206         credential_write_item(fp, "host", c->host);
 207         credential_write_item(fp, "path", c->path);
 208         credential_write_item(fp, "username", c->username);
 209         credential_write_item(fp, "password", c->password);
 210 }
 211
 212 static int run_credential_helper(struct credential *c,
 213                                  const char *cmd,
 214                                  int want_output)
 215 {
 216         struct child_process helper = CHILD_PROCESS_INIT;
 217         const char *argv[] = { NULL, NULL };
 218         FILE *fp;
 219
 220         argv[0] = cmd;
 221         helper.argv = argv;
 222         helper.use_shell = 1;
 223         helper.in = -1;
 224         if (want_output)
 225                 helper.out = -1;
 226         else
 227                 helper.no_stdout = 1;
 228
 229         if (start_command(&helper) < 0)
 230                 return -1;
 231
 232         fp = xfdopen(helper.in, "w");
 233         sigchain_push(SIGPIPE, SIG_IGN);
 234         credential_write(c, fp);
 235         fclose(fp);
 236         sigchain_pop(SIGPIPE);
 237
 238         if (want_output) {
 239                 int r;
 240                 fp = xfdopen(helper.out, "r");
 241                 r = credential_read(c, fp);
 242                 fclose(fp);
 243                 if (r < 0) {
 244                         finish_command(&helper);
 245                         return -1;
 246                 }
 247         }
 248
 249         if (finish_command(&helper))
 250                 return -1;
 251         return 0;
 252 }
 253
 254 static int credential_do(struct credential *c, const char *helper,
 255                          const char *operation)
 256 {
 257         struct strbuf cmd = STRBUF_INIT;
 258         int r;
 259
 260         if (helper[0] == '!')
 261                 strbuf_addstr(&cmd, helper + 1);
 262         else if (is_absolute_path(helper))
 263                 strbuf_addstr(&cmd, helper);
 264         else
 265                 strbuf_addf(&cmd, "git credential-%s", helper);
 266
 267         strbuf_addf(&cmd, " %s", operation);
 268         r = run_credential_helper(c, cmd.buf, !strcmp(operation, "get"));
 269
 270         strbuf_release(&cmd);
 271         return r;
 272 }
 273
 274 void credential_fill(struct credential *c)
 275 {
 276         int i;
 277
 278         if (c->username && c->password)
 279                 return;
 280
 281         credential_apply_config(c);
 282
 283         for (i = 0; i < c->helpers.nr; i++) {
 284                 credential_do(c, c->helpers.items[i].string, "get");
 285                 if (c->username && c->password)
 286                         return;
 287                 if (c->quit)
 288                         die("credential helper '%s' told us to quit",
 289                             c->helpers.items[i].string);
 290         }
 291
 292         credential_getpass(c);
 293         if (!c->username && !c->password)
 294                 die("unable to get password from user");
 295 }
 296
 297 void credential_approve(struct credential *c)
 298 {
 299         int i;
 300
 301         if (c->approved)
 302                 return;
 303         if (!c->username || !c->password)
 304                 return;
 305
 306         credential_apply_config(c);
 307
 308         for (i = 0; i < c->helpers.nr; i++)
 309                 credential_do(c, c->helpers.items[i].string, "store");
 310         c->approved = 1;
 311 }
 312
 313 void credential_reject(struct credential *c)
 314 {
 315         int i;
 316
 317         credential_apply_config(c);
 318
 319         for (i = 0; i < c->helpers.nr; i++)
 320                 credential_do(c, c->helpers.items[i].string, "erase");
 321
 322         FREE_AND_NULL(c->username);
 323         FREE_AND_NULL(c->password);
 324         c->approved = 0;
 325 }
 326
 327 static int check_url_component(const char *url, int quiet,
 328                                const char *name, const char *value)
 329 {
 330         if (!value)
 331                 return 0;
 332         if (!strchr(value, '\n'))
 333                 return 0;
 334
 335         if (!quiet)
 336                 warning(_("url contains a newline in its %s component: %s"),
 337                         name, url);
 338         return -1;
 339 }
 340
 341 int credential_from_url_gently(struct credential *c, const char *url,
 342                                int quiet)
 343 {
 344         const char *at, *colon, *cp, *slash, *host, *proto_end;
 345
 346         credential_clear(c);
 347
 348         /*
 349          * Match one of:
 350          *   (1) proto://<host>/...
 351          *   (2) proto://<user>@<host>/...
 352          *   (3) proto://<user>:<pass>@<host>/...
 353          */
 354         proto_end = strstr(url, "://");
 355         if (!proto_end)
 356                 return 0;
 357         cp = proto_end + 3;
 358         at = strchr(cp, '@');
 359         colon = strchr(cp, ':');
 360         slash = strchrnul(cp, '/');
 361
 362         if (!at || slash <= at) {
 363                 /* Case (1) */
 364                 host = cp;
 365         }
 366         else if (!colon || at <= colon) {
 367                 /* Case (2) */
 368                 c->username = url_decode_mem(cp, at - cp);
 369                 host = at + 1;
 370         } else {
 371                 /* Case (3) */
 372                 c->username = url_decode_mem(cp, colon - cp);
 373                 c->password = url_decode_mem(colon + 1, at - (colon + 1));
 374                 host = at + 1;
 375         }
 376
 377         if (proto_end - url > 0)
 378                 c->protocol = xmemdupz(url, proto_end - url);
 379         if (slash - host > 0)
 380                 c->host = url_decode_mem(host, slash - host);
 381         /* Trim leading and trailing slashes from path */
 382         while (*slash == '/')
 383                 slash++;
 384         if (*slash) {
 385                 char *p;
 386                 c->path = url_decode(slash);
 387                 p = c->path + strlen(c->path) - 1;
 388                 while (p > c->path && *p == '/')
 389                         *p-- = '\0';
 390         }
 391
 392         if (check_url_component(url, quiet, "username", c->username) < 0 ||
 393             check_url_component(url, quiet, "password", c->password) < 0 ||
 394             check_url_component(url, quiet, "protocol", c->protocol) < 0 ||
 395             check_url_component(url, quiet, "host", c->host) < 0 ||
 396             check_url_component(url, quiet, "path", c->path) < 0)
 397                 return -1;
 398
 399         return 0;
 400 }
 401
 402 void credential_from_url(struct credential *c, const char *url)
 403 {
 404         if (credential_from_url_gently(c, url, 0) < 0) {
 405                 warning(_("skipping credential lookup for url: %s"), url);
 406                 credential_clear(c);
 407         }
 408 }