| 1 | #define USE_THE_REPOSITORY_VARIABLE |
| 2 | #include "builtin.h" |
| 3 | #include "abspath.h" |
| 4 | #include "gettext.h" |
| 5 | #include "parse-options.h" |
| 6 | #include "path.h" |
| 7 | |
| 8 | #ifndef NO_UNIX_SOCKETS |
| 9 | |
| 10 | #include "config.h" |
| 11 | #include "tempfile.h" |
| 12 | #include "credential.h" |
| 13 | #include "unix-socket.h" |
| 14 | |
| 15 | struct credential_cache_entry { |
| 16 | struct credential item; |
| 17 | timestamp_t expiration; |
| 18 | }; |
| 19 | static struct credential_cache_entry *entries; |
| 20 | static int entries_nr; |
| 21 | static int entries_alloc; |
| 22 | |
| 23 | static void cache_credential(struct credential *c, int timeout) |
| 24 | { |
| 25 | struct credential_cache_entry *e; |
| 26 | |
| 27 | ALLOC_GROW(entries, entries_nr + 1, entries_alloc); |
| 28 | e = &entries[entries_nr++]; |
| 29 | |
| 30 | /* take ownership of pointers */ |
| 31 | memcpy(&e->item, c, sizeof(*c)); |
| 32 | memset(c, 0, sizeof(*c)); |
| 33 | e->expiration = time(NULL) + timeout; |
| 34 | } |
| 35 | |
| 36 | static struct credential_cache_entry *lookup_credential(const struct credential *c) |
| 37 | { |
| 38 | int i; |
| 39 | for (i = 0; i < entries_nr; i++) { |
| 40 | struct credential *e = &entries[i].item; |
| 41 | if (credential_match(c, e, 0)) |
| 42 | return &entries[i]; |
| 43 | } |
| 44 | return NULL; |
| 45 | } |
| 46 | |
| 47 | static void remove_credential(const struct credential *c, int match_password) |
| 48 | { |
| 49 | struct credential_cache_entry *e; |
| 50 | |
| 51 | int i; |
| 52 | for (i = 0; i < entries_nr; i++) { |
| 53 | e = &entries[i]; |
| 54 | if (credential_match(c, &e->item, match_password)) |
| 55 | e->expiration = 0; |
| 56 | } |
| 57 | } |
| 58 | |
| 59 | static timestamp_t check_expirations(void) |
| 60 | { |
| 61 | static timestamp_t wait_for_entry_until; |
| 62 | int i = 0; |
| 63 | timestamp_t now = time(NULL); |
| 64 | timestamp_t next = TIME_MAX; |
| 65 | |
| 66 | /* |
| 67 | * Initially give the client 30 seconds to actually contact us |
| 68 | * and store a credential before we decide there's no point in |
| 69 | * keeping the daemon around. |
| 70 | */ |
| 71 | if (!wait_for_entry_until) |
| 72 | wait_for_entry_until = now + 30; |
| 73 | |
| 74 | while (i < entries_nr) { |
| 75 | if (entries[i].expiration <= now) { |
| 76 | entries_nr--; |
| 77 | credential_clear(&entries[i].item); |
| 78 | if (i != entries_nr) |
| 79 | memcpy(&entries[i], &entries[entries_nr], sizeof(*entries)); |
| 80 | /* |
| 81 | * Stick around 30 seconds in case a new credential |
| 82 | * shows up (e.g., because we just removed a failed |
| 83 | * one, and we will soon get the correct one). |
| 84 | */ |
| 85 | wait_for_entry_until = now + 30; |
| 86 | } |
| 87 | else { |
| 88 | if (entries[i].expiration < next) |
| 89 | next = entries[i].expiration; |
| 90 | i++; |
| 91 | } |
| 92 | } |
| 93 | |
| 94 | if (!entries_nr) { |
| 95 | if (wait_for_entry_until <= now) |
| 96 | return 0; |
| 97 | next = wait_for_entry_until; |
| 98 | } |
| 99 | |
| 100 | return next - now; |
| 101 | } |
| 102 | |
| 103 | static int read_request(FILE *fh, struct credential *c, |
| 104 | struct strbuf *action, int *timeout) |
| 105 | { |
| 106 | static struct strbuf item = STRBUF_INIT; |
| 107 | const char *p; |
| 108 | |
| 109 | strbuf_getline_lf(&item, fh); |
| 110 | if (!skip_prefix(item.buf, "action=", &p)) |
| 111 | return error("client sent bogus action line: %s", item.buf); |
| 112 | strbuf_addstr(action, p); |
| 113 | |
| 114 | strbuf_getline_lf(&item, fh); |
| 115 | if (!skip_prefix(item.buf, "timeout=", &p)) |
| 116 | return error("client sent bogus timeout line: %s", item.buf); |
| 117 | *timeout = atoi(p); |
| 118 | |
| 119 | credential_set_all_capabilities(c, CREDENTIAL_OP_INITIAL); |
| 120 | |
| 121 | if (credential_read(c, fh, CREDENTIAL_OP_HELPER) < 0) |
| 122 | return -1; |
| 123 | return 0; |
| 124 | } |
| 125 | |
| 126 | static void serve_one_client(FILE *in, FILE *out) |
| 127 | { |
| 128 | struct credential c = CREDENTIAL_INIT; |
| 129 | struct strbuf action = STRBUF_INIT; |
| 130 | int timeout = -1; |
| 131 | |
| 132 | if (read_request(in, &c, &action, &timeout) < 0) |
| 133 | /* ignore error */ ; |
| 134 | else if (!strcmp(action.buf, "get")) { |
| 135 | struct credential_cache_entry *e = lookup_credential(&c); |
| 136 | if (e) { |
| 137 | e->item.capa_authtype.request_initial = 1; |
| 138 | e->item.capa_authtype.request_helper = 1; |
| 139 | |
| 140 | fprintf(out, "capability[]=authtype\n"); |
| 141 | if (e->item.username) |
| 142 | fprintf(out, "username=%s\n", e->item.username); |
| 143 | if (e->item.password) |
| 144 | fprintf(out, "password=%s\n", e->item.password); |
| 145 | if (credential_has_capability(&c.capa_authtype, CREDENTIAL_OP_RESPONSE) && e->item.authtype) |
| 146 | fprintf(out, "authtype=%s\n", e->item.authtype); |
| 147 | if (credential_has_capability(&c.capa_authtype, CREDENTIAL_OP_RESPONSE) && e->item.credential) |
| 148 | fprintf(out, "credential=%s\n", e->item.credential); |
| 149 | if (e->item.password_expiry_utc != TIME_MAX) |
| 150 | fprintf(out, "password_expiry_utc=%"PRItime"\n", |
| 151 | e->item.password_expiry_utc); |
| 152 | if (e->item.oauth_refresh_token) |
| 153 | fprintf(out, "oauth_refresh_token=%s\n", |
| 154 | e->item.oauth_refresh_token); |
| 155 | } |
| 156 | } |
| 157 | else if (!strcmp(action.buf, "exit")) { |
| 158 | /* |
| 159 | * It's important that we clean up our socket first, and then |
| 160 | * signal the client only once we have finished the cleanup. |
| 161 | * Calling exit() directly does this, because we clean up in |
| 162 | * our atexit() handler, and then signal the client when our |
| 163 | * process actually ends, which closes the socket and gives |
| 164 | * them EOF. |
| 165 | */ |
| 166 | exit(0); |
| 167 | } |
| 168 | else if (!strcmp(action.buf, "erase")) |
| 169 | remove_credential(&c, 1); |
| 170 | else if (!strcmp(action.buf, "store")) { |
| 171 | if (timeout < 0) |
| 172 | warning("cache client didn't specify a timeout"); |
| 173 | else if ((!c.username || !c.password) && (!c.authtype && !c.credential)) |
| 174 | warning("cache client gave us a partial credential"); |
| 175 | else if (c.ephemeral) |
| 176 | warning("not storing ephemeral credential"); |
| 177 | else { |
| 178 | remove_credential(&c, 0); |
| 179 | cache_credential(&c, timeout); |
| 180 | } |
| 181 | } |
| 182 | else |
| 183 | warning("cache client sent unknown action: %s", action.buf); |
| 184 | |
| 185 | credential_clear(&c); |
| 186 | strbuf_release(&action); |
| 187 | } |
| 188 | |
| 189 | static int serve_cache_loop(int fd) |
| 190 | { |
| 191 | struct pollfd pfd; |
| 192 | timestamp_t wakeup; |
| 193 | |
| 194 | wakeup = check_expirations(); |
| 195 | if (!wakeup) |
| 196 | return 0; |
| 197 | |
| 198 | pfd.fd = fd; |
| 199 | pfd.events = POLLIN; |
| 200 | if (poll(&pfd, 1, 1000 * wakeup) < 0) { |
| 201 | if (errno != EINTR) |
| 202 | die_errno("poll failed"); |
| 203 | return 1; |
| 204 | } |
| 205 | |
| 206 | if (pfd.revents & POLLIN) { |
| 207 | int client, client2; |
| 208 | FILE *in, *out; |
| 209 | |
| 210 | client = accept(fd, NULL, NULL); |
| 211 | if (client < 0) { |
| 212 | warning_errno("accept failed"); |
| 213 | return 1; |
| 214 | } |
| 215 | client2 = dup(client); |
| 216 | if (client2 < 0) { |
| 217 | warning_errno("dup failed"); |
| 218 | close(client); |
| 219 | return 1; |
| 220 | } |
| 221 | |
| 222 | in = xfdopen(client, "r"); |
| 223 | out = xfdopen(client2, "w"); |
| 224 | serve_one_client(in, out); |
| 225 | fclose(in); |
| 226 | fclose(out); |
| 227 | } |
| 228 | return 1; |
| 229 | } |
| 230 | |
| 231 | static void serve_cache(const char *socket_path, int debug) |
| 232 | { |
| 233 | struct unix_stream_listen_opts opts = UNIX_STREAM_LISTEN_OPTS_INIT; |
| 234 | int fd; |
| 235 | |
| 236 | fd = unix_stream_listen(socket_path, &opts); |
| 237 | if (fd < 0) |
| 238 | die_errno("unable to bind to '%s'", socket_path); |
| 239 | |
| 240 | printf("ok\n"); |
| 241 | fclose(stdout); |
| 242 | if (!debug) { |
| 243 | if (!freopen("/dev/null", "w", stderr)) |
| 244 | die_errno("unable to point stderr to /dev/null"); |
| 245 | } |
| 246 | |
| 247 | while (serve_cache_loop(fd)) |
| 248 | ; /* nothing */ |
| 249 | |
| 250 | close(fd); |
| 251 | } |
| 252 | |
| 253 | static const char permissions_advice[] = N_( |
| 254 | "The permissions on your socket directory are too loose; other\n" |
| 255 | "users may be able to read your cached credentials. Consider running:\n" |
| 256 | "\n" |
| 257 | " chmod 0700 %s"); |
| 258 | static void init_socket_directory(const char *path) |
| 259 | { |
| 260 | struct stat st; |
| 261 | char *path_copy = xstrdup(path); |
| 262 | char *dir = dirname(path_copy); |
| 263 | |
| 264 | if (!stat(dir, &st)) { |
| 265 | if (st.st_mode & 077) |
| 266 | die(_(permissions_advice), dir); |
| 267 | } else { |
| 268 | /* |
| 269 | * We must be sure to create the directory with the correct mode, |
| 270 | * not just chmod it after the fact; otherwise, there is a race |
| 271 | * condition in which somebody can chdir to it, sleep, then try to open |
| 272 | * our protected socket. |
| 273 | */ |
| 274 | if (safe_create_leading_directories_const(the_repository, dir) < 0) |
| 275 | die_errno("unable to create directories for '%s'", dir); |
| 276 | if (mkdir(dir, 0700) < 0) |
| 277 | die_errno("unable to mkdir '%s'", dir); |
| 278 | } |
| 279 | |
| 280 | if (chdir(dir)) |
| 281 | /* |
| 282 | * We don't actually care what our cwd is; we chdir here just to |
| 283 | * be a friendly daemon and avoid tying up our original cwd. |
| 284 | * If this fails, it's OK to just continue without that benefit. |
| 285 | */ |
| 286 | ; |
| 287 | |
| 288 | free(path_copy); |
| 289 | } |
| 290 | |
| 291 | int cmd_credential_cache_daemon(int argc, |
| 292 | const char **argv, |
| 293 | const char *prefix, |
| 294 | struct repository *repo UNUSED) |
| 295 | { |
| 296 | struct tempfile *socket_file; |
| 297 | const char *socket_path; |
| 298 | int ignore_sighup = 0; |
| 299 | static const char *usage[] = { |
| 300 | "git credential-cache--daemon [--debug] <socket-path>", |
| 301 | NULL |
| 302 | }; |
| 303 | int debug = 0; |
| 304 | const struct option options[] = { |
| 305 | OPT_BOOL(0, "debug", &debug, |
| 306 | N_("print debugging messages to stderr")), |
| 307 | OPT_END() |
| 308 | }; |
| 309 | |
| 310 | repo_config_get_bool(the_repository, "credentialcache.ignoresighup", &ignore_sighup); |
| 311 | |
| 312 | argc = parse_options(argc, argv, prefix, options, usage, 0); |
| 313 | socket_path = argv[0]; |
| 314 | |
| 315 | if (!have_unix_sockets()) |
| 316 | die(_("credential-cache--daemon unavailable; no unix socket support")); |
| 317 | if (!socket_path) |
| 318 | usage_with_options(usage, options); |
| 319 | |
| 320 | if (!is_absolute_path(socket_path)) |
| 321 | die("socket directory must be an absolute path"); |
| 322 | |
| 323 | init_socket_directory(socket_path); |
| 324 | socket_file = register_tempfile(socket_path); |
| 325 | |
| 326 | if (ignore_sighup) |
| 327 | signal(SIGHUP, SIG_IGN); |
| 328 | |
| 329 | serve_cache(socket_path, debug); |
| 330 | delete_tempfile(&socket_file); |
| 331 | |
| 332 | return 0; |
| 333 | } |
| 334 | |
| 335 | #else |
| 336 | |
| 337 | int cmd_credential_cache_daemon(int argc, |
| 338 | const char **argv, |
| 339 | const char *prefix, |
| 340 | struct repository *repo UNUSED) |
| 341 | { |
| 342 | const char * const usage[] = { |
| 343 | "git credential-cache--daemon [--debug] <socket-path>", |
| 344 | "", |
| 345 | "credential-cache--daemon is disabled in this build of Git", |
| 346 | NULL |
| 347 | }; |
| 348 | struct option options[] = { OPT_END() }; |
| 349 | |
| 350 | argc = parse_options(argc, argv, prefix, options, usage, 0); |
| 351 | die(_("credential-cache--daemon unavailable; no unix socket support")); |
| 352 | } |
| 353 | |
| 354 | #endif /* NO_UNIX_SOCKET */ |