send-pack.c

   1 #include "builtin.h"
   2 #include "config.h"
   3 #include "commit.h"
   4 #include "refs.h"
   5 #include "object-store.h"
   6 #include "pkt-line.h"
   7 #include "sideband.h"
   8 #include "run-command.h"
   9 #include "remote.h"
  10 #include "connect.h"
  11 #include "send-pack.h"
  12 #include "quote.h"
  13 #include "transport.h"
  14 #include "version.h"
  15 #include "sha1-array.h"
  16 #include "gpg-interface.h"
  17 #include "cache.h"
  18 #include "shallow.h"
  19
  20 int option_parse_push_signed(const struct option *opt,
  21                              const char *arg, int unset)
  22 {
  23         if (unset) {
  24                 *(int *)(opt->value) = SEND_PACK_PUSH_CERT_NEVER;
  25                 return 0;
  26         }
  27         switch (git_parse_maybe_bool(arg)) {
  28         case 1:
  29                 *(int *)(opt->value) = SEND_PACK_PUSH_CERT_ALWAYS;
  30                 return 0;
  31         case 0:
  32                 *(int *)(opt->value) = SEND_PACK_PUSH_CERT_NEVER;
  33                 return 0;
  34         }
  35         if (!strcasecmp("if-asked", arg)) {
  36                 *(int *)(opt->value) = SEND_PACK_PUSH_CERT_IF_ASKED;
  37                 return 0;
  38         }
  39         die("bad %s argument: %s", opt->long_name, arg);
  40 }
  41
  42 static void feed_object(const struct object_id *oid, FILE *fh, int negative)
  43 {
  44         if (negative &&
  45             !has_object_file_with_flags(oid,
  46                                         OBJECT_INFO_SKIP_FETCH_OBJECT |
  47                                         OBJECT_INFO_QUICK))
  48                 return;
  49
  50         if (negative)
  51                 putc('^', fh);
  52         fputs(oid_to_hex(oid), fh);
  53         putc('\n', fh);
  54 }
  55
  56 /*
  57  * Make a pack stream and spit it out into file descriptor fd
  58  */
  59 static int pack_objects(int fd, struct ref *refs, struct oid_array *extra, struct send_pack_args *args)
  60 {
  61         /*
  62          * The child becomes pack-objects --revs; we feed
  63          * the revision parameters to it via its stdin and
  64          * let its stdout go back to the other end.
  65          */
  66         struct child_process po = CHILD_PROCESS_INIT;
  67         FILE *po_in;
  68         int i;
  69         int rc;
  70
  71         argv_array_push(&po.args, "pack-objects");
  72         argv_array_push(&po.args, "--all-progress-implied");
  73         argv_array_push(&po.args, "--revs");
  74         argv_array_push(&po.args, "--stdout");
  75         if (args->use_thin_pack)
  76                 argv_array_push(&po.args, "--thin");
  77         if (args->use_ofs_delta)
  78                 argv_array_push(&po.args, "--delta-base-offset");
  79         if (args->quiet || !args->progress)
  80                 argv_array_push(&po.args, "-q");
  81         if (args->progress)
  82                 argv_array_push(&po.args, "--progress");
  83         if (is_repository_shallow(the_repository))
  84                 argv_array_push(&po.args, "--shallow");
  85         po.in = -1;
  86         po.out = args->stateless_rpc ? -1 : fd;
  87         po.git_cmd = 1;
  88         if (start_command(&po))
  89                 die_errno("git pack-objects failed");
  90
  91         /*
  92          * We feed the pack-objects we just spawned with revision
  93          * parameters by writing to the pipe.
  94          */
  95         po_in = xfdopen(po.in, "w");
  96         for (i = 0; i < extra->nr; i++)
  97                 feed_object(&extra->oid[i], po_in, 1);
  98
  99         while (refs) {
 100                 if (!is_null_oid(&refs->old_oid))
 101                         feed_object(&refs->old_oid, po_in, 1);
 102                 if (!is_null_oid(&refs->new_oid))
 103                         feed_object(&refs->new_oid, po_in, 0);
 104                 refs = refs->next;
 105         }
 106
 107         fflush(po_in);
 108         if (ferror(po_in))
 109                 die_errno("error writing to pack-objects");
 110         fclose(po_in);
 111
 112         if (args->stateless_rpc) {
 113                 char *buf = xmalloc(LARGE_PACKET_MAX);
 114                 while (1) {
 115                         ssize_t n = xread(po.out, buf, LARGE_PACKET_MAX);
 116                         if (n <= 0)
 117                                 break;
 118                         send_sideband(fd, -1, buf, n, LARGE_PACKET_MAX);
 119                 }
 120                 free(buf);
 121                 close(po.out);
 122                 po.out = -1;
 123         }
 124
 125         rc = finish_command(&po);
 126         if (rc) {
 127                 /*
 128                  * For a normal non-zero exit, we assume pack-objects wrote
 129                  * something useful to stderr. For death by signal, though,
 130                  * we should mention it to the user. The exception is SIGPIPE
 131                  * (141), because that's a normal occurrence if the remote end
 132                  * hangs up (and we'll report that by trying to read the unpack
 133                  * status).
 134                  */
 135                 if (rc > 128 && rc != 141)
 136                         error("pack-objects died of signal %d", rc - 128);
 137                 return -1;
 138         }
 139         return 0;
 140 }
 141
 142 static int receive_unpack_status(struct packet_reader *reader)
 143 {
 144         if (packet_reader_read(reader) != PACKET_READ_NORMAL)
 145                 return error(_("unexpected flush packet while reading remote unpack status"));
 146         if (!skip_prefix(reader->line, "unpack ", &reader->line))
 147                 return error(_("unable to parse remote unpack status: %s"), reader->line);
 148         if (strcmp(reader->line, "ok"))
 149                 return error(_("remote unpack failed: %s"), reader->line);
 150         return 0;
 151 }
 152
 153 static int receive_status(struct packet_reader *reader, struct ref *refs)
 154 {
 155         struct ref *hint;
 156         int ret;
 157
 158         hint = NULL;
 159         ret = receive_unpack_status(reader);
 160         while (1) {
 161                 const char *refname;
 162                 char *msg;
 163                 if (packet_reader_read(reader) != PACKET_READ_NORMAL)
 164                         break;
 165                 if (!starts_with(reader->line, "ok ") && !starts_with(reader->line, "ng ")) {
 166                         error("invalid ref status from remote: %s", reader->line);
 167                         ret = -1;
 168                         break;
 169                 }
 170
 171                 refname = reader->line + 3;
 172                 msg = strchr(refname, ' ');
 173                 if (msg)
 174                         *msg++ = '\0';
 175
 176                 /* first try searching at our hint, falling back to all refs */
 177                 if (hint)
 178                         hint = find_ref_by_name(hint, refname);
 179                 if (!hint)
 180                         hint = find_ref_by_name(refs, refname);
 181                 if (!hint) {
 182                         warning("remote reported status on unknown ref: %s",
 183                                         refname);
 184                         continue;
 185                 }
 186                 if (hint->status != REF_STATUS_EXPECTING_REPORT) {
 187                         warning("remote reported status on unexpected ref: %s",
 188                                         refname);
 189                         continue;
 190                 }
 191
 192                 if (reader->line[0] == 'o' && reader->line[1] == 'k')
 193                         hint->status = REF_STATUS_OK;
 194                 else {
 195                         hint->status = REF_STATUS_REMOTE_REJECT;
 196                         ret = -1;
 197                 }
 198                 hint->remote_status = xstrdup_or_null(msg);
 199                 /* start our next search from the next ref */
 200                 hint = hint->next;
 201         }
 202         return ret;
 203 }
 204
 205 static int sideband_demux(int in, int out, void *data)
 206 {
 207         int *fd = data, ret;
 208         if (async_with_fork())
 209                 close(fd[1]);
 210         ret = recv_sideband("send-pack", fd[0], out);
 211         close(out);
 212         return ret;
 213 }
 214
 215 static int advertise_shallow_grafts_cb(const struct commit_graft *graft, void *cb)
 216 {
 217         struct strbuf *sb = cb;
 218         if (graft->nr_parent == -1)
 219                 packet_buf_write(sb, "shallow %s\n", oid_to_hex(&graft->oid));
 220         return 0;
 221 }
 222
 223 static void advertise_shallow_grafts_buf(struct strbuf *sb)
 224 {
 225         if (!is_repository_shallow(the_repository))
 226                 return;
 227         for_each_commit_graft(advertise_shallow_grafts_cb, sb);
 228 }
 229
 230 #define CHECK_REF_NO_PUSH -1
 231 #define CHECK_REF_STATUS_REJECTED -2
 232 #define CHECK_REF_UPTODATE -3
 233 static int check_to_send_update(const struct ref *ref, const struct send_pack_args *args)
 234 {
 235         if (!ref->peer_ref && !args->send_mirror)
 236                 return CHECK_REF_NO_PUSH;
 237
 238         /* Check for statuses set by set_ref_status_for_push() */
 239         switch (ref->status) {
 240         case REF_STATUS_REJECT_NONFASTFORWARD:
 241         case REF_STATUS_REJECT_ALREADY_EXISTS:
 242         case REF_STATUS_REJECT_FETCH_FIRST:
 243         case REF_STATUS_REJECT_NEEDS_FORCE:
 244         case REF_STATUS_REJECT_STALE:
 245         case REF_STATUS_REJECT_NODELETE:
 246                 return CHECK_REF_STATUS_REJECTED;
 247         case REF_STATUS_UPTODATE:
 248                 return CHECK_REF_UPTODATE;
 249         default:
 250                 return 0;
 251         }
 252 }
 253
 254 /*
 255  * the beginning of the next line, or the end of buffer.
 256  *
 257  * NEEDSWORK: perhaps move this to git-compat-util.h or somewhere and
 258  * convert many similar uses found by "git grep -A4 memchr".
 259  */
 260 static const char *next_line(const char *line, size_t len)
 261 {
 262         const char *nl = memchr(line, '\n', len);
 263         if (!nl)
 264                 return line + len; /* incomplete line */
 265         return nl + 1;
 266 }
 267
 268 static int generate_push_cert(struct strbuf *req_buf,
 269                               const struct ref *remote_refs,
 270                               struct send_pack_args *args,
 271                               const char *cap_string,
 272                               const char *push_cert_nonce)
 273 {
 274         const struct ref *ref;
 275         struct string_list_item *item;
 276         char *signing_key = xstrdup(get_signing_key());
 277         const char *cp, *np;
 278         struct strbuf cert = STRBUF_INIT;
 279         int update_seen = 0;
 280
 281         strbuf_addstr(&cert, "certificate version 0.1\n");
 282         strbuf_addf(&cert, "pusher %s ", signing_key);
 283         datestamp(&cert);
 284         strbuf_addch(&cert, '\n');
 285         if (args->url && *args->url) {
 286                 char *anon_url = transport_anonymize_url(args->url);
 287                 strbuf_addf(&cert, "pushee %s\n", anon_url);
 288                 free(anon_url);
 289         }
 290         if (push_cert_nonce[0])
 291                 strbuf_addf(&cert, "nonce %s\n", push_cert_nonce);
 292         if (args->push_options)
 293                 for_each_string_list_item(item, args->push_options)
 294                         strbuf_addf(&cert, "push-option %s\n", item->string);
 295         strbuf_addstr(&cert, "\n");
 296
 297         for (ref = remote_refs; ref; ref = ref->next) {
 298                 if (check_to_send_update(ref, args) < 0)
 299                         continue;
 300                 update_seen = 1;
 301                 strbuf_addf(&cert, "%s %s %s\n",
 302                             oid_to_hex(&ref->old_oid),
 303                             oid_to_hex(&ref->new_oid),
 304                             ref->name);
 305         }
 306         if (!update_seen)
 307                 goto free_return;
 308
 309         if (sign_buffer(&cert, &cert, signing_key))
 310                 die(_("failed to sign the push certificate"));
 311
 312         packet_buf_write(req_buf, "push-cert%c%s", 0, cap_string);
 313         for (cp = cert.buf; cp < cert.buf + cert.len; cp = np) {
 314                 np = next_line(cp, cert.buf + cert.len - cp);
 315                 packet_buf_write(req_buf,
 316                                  "%.*s", (int)(np - cp), cp);
 317         }
 318         packet_buf_write(req_buf, "push-cert-end\n");
 319
 320 free_return:
 321         free(signing_key);
 322         strbuf_release(&cert);
 323         return update_seen;
 324 }
 325
 326
 327 static int atomic_push_failure(struct send_pack_args *args,
 328                                struct ref *remote_refs,
 329                                struct ref *failing_ref)
 330 {
 331         struct ref *ref;
 332         /* Mark other refs as failed */
 333         for (ref = remote_refs; ref; ref = ref->next) {
 334                 if (!ref->peer_ref && !args->send_mirror)
 335                         continue;
 336
 337                 switch (ref->status) {
 338                 case REF_STATUS_EXPECTING_REPORT:
 339                         ref->status = REF_STATUS_ATOMIC_PUSH_FAILED;
 340                         continue;
 341                 default:
 342                         break; /* do nothing */
 343                 }
 344         }
 345         return error("atomic push failed for ref %s. status: %d\n",
 346                      failing_ref->name, failing_ref->status);
 347 }
 348
 349 #define NONCE_LEN_LIMIT 256
 350
 351 static void reject_invalid_nonce(const char *nonce, int len)
 352 {
 353         int i = 0;
 354
 355         if (NONCE_LEN_LIMIT <= len)
 356                 die("the receiving end asked to sign an invalid nonce <%.*s>",
 357                     len, nonce);
 358
 359         for (i = 0; i < len; i++) {
 360                 int ch = nonce[i] & 0xFF;
 361                 if (isalnum(ch) ||
 362                     ch == '-' || ch == '.' ||
 363                     ch == '/' || ch == '+' ||
 364                     ch == '=' || ch == '_')
 365                         continue;
 366                 die("the receiving end asked to sign an invalid nonce <%.*s>",
 367                     len, nonce);
 368         }
 369 }
 370
 371 int send_pack(struct send_pack_args *args,
 372               int fd[], struct child_process *conn,
 373               struct ref *remote_refs,
 374               struct oid_array *extra_have)
 375 {
 376         int in = fd[0];
 377         int out = fd[1];
 378         struct strbuf req_buf = STRBUF_INIT;
 379         struct strbuf cap_buf = STRBUF_INIT;
 380         struct ref *ref;
 381         int need_pack_data = 0;
 382         int allow_deleting_refs = 0;
 383         int status_report = 0;
 384         int use_sideband = 0;
 385         int quiet_supported = 0;
 386         int agent_supported = 0;
 387         int use_atomic = 0;
 388         int atomic_supported = 0;
 389         int use_push_options = 0;
 390         int push_options_supported = 0;
 391         unsigned cmds_sent = 0;
 392         int ret;
 393         struct async demux;
 394         const char *push_cert_nonce = NULL;
 395         struct packet_reader reader;
 396
 397         /* Does the other end support the reporting? */
 398         if (server_supports("report-status"))
 399                 status_report = 1;
 400         if (server_supports("delete-refs"))
 401                 allow_deleting_refs = 1;
 402         if (server_supports("ofs-delta"))
 403                 args->use_ofs_delta = 1;
 404         if (server_supports("side-band-64k"))
 405                 use_sideband = 1;
 406         if (server_supports("quiet"))
 407                 quiet_supported = 1;
 408         if (server_supports("agent"))
 409                 agent_supported = 1;
 410         if (server_supports("no-thin"))
 411                 args->use_thin_pack = 0;
 412         if (server_supports("atomic"))
 413                 atomic_supported = 1;
 414         if (server_supports("push-options"))
 415                 push_options_supported = 1;
 416
 417         if (args->push_cert != SEND_PACK_PUSH_CERT_NEVER) {
 418                 int len;
 419                 push_cert_nonce = server_feature_value("push-cert", &len);
 420                 if (push_cert_nonce) {
 421                         reject_invalid_nonce(push_cert_nonce, len);
 422                         push_cert_nonce = xmemdupz(push_cert_nonce, len);
 423                 } else if (args->push_cert == SEND_PACK_PUSH_CERT_ALWAYS) {
 424                         die(_("the receiving end does not support --signed push"));
 425                 } else if (args->push_cert == SEND_PACK_PUSH_CERT_IF_ASKED) {
 426                         warning(_("not sending a push certificate since the"
 427                                   " receiving end does not support --signed"
 428                                   " push"));
 429                 }
 430         }
 431
 432         if (!remote_refs) {
 433                 fprintf(stderr, "No refs in common and none specified; doing nothing.\n"
 434                         "Perhaps you should specify a branch such as 'master'.\n");
 435                 return 0;
 436         }
 437         if (args->atomic && !atomic_supported)
 438                 die(_("the receiving end does not support --atomic push"));
 439
 440         use_atomic = atomic_supported && args->atomic;
 441
 442         if (args->push_options && !push_options_supported)
 443                 die(_("the receiving end does not support push options"));
 444
 445         use_push_options = push_options_supported && args->push_options;
 446
 447         if (status_report)
 448                 strbuf_addstr(&cap_buf, " report-status");
 449         if (use_sideband)
 450                 strbuf_addstr(&cap_buf, " side-band-64k");
 451         if (quiet_supported && (args->quiet || !args->progress))
 452                 strbuf_addstr(&cap_buf, " quiet");
 453         if (use_atomic)
 454                 strbuf_addstr(&cap_buf, " atomic");
 455         if (use_push_options)
 456                 strbuf_addstr(&cap_buf, " push-options");
 457         if (agent_supported)
 458                 strbuf_addf(&cap_buf, " agent=%s", git_user_agent_sanitized());
 459
 460         /*
 461          * NEEDSWORK: why does delete-refs have to be so specific to
 462          * send-pack machinery that set_ref_status_for_push() cannot
 463          * set this bit for us???
 464          */
 465         for (ref = remote_refs; ref; ref = ref->next)
 466                 if (ref->deletion && !allow_deleting_refs)
 467                         ref->status = REF_STATUS_REJECT_NODELETE;
 468
 469         if (!args->dry_run)
 470                 advertise_shallow_grafts_buf(&req_buf);
 471
 472         if (!args->dry_run && push_cert_nonce)
 473                 cmds_sent = generate_push_cert(&req_buf, remote_refs, args,
 474                                                cap_buf.buf, push_cert_nonce);
 475
 476         /*
 477          * Clear the status for each ref and see if we need to send
 478          * the pack data.
 479          */
 480         for (ref = remote_refs; ref; ref = ref->next) {
 481                 switch (check_to_send_update(ref, args)) {
 482                 case 0: /* no error */
 483                         break;
 484                 case CHECK_REF_STATUS_REJECTED:
 485                         /*
 486                          * When we know the server would reject a ref update if
 487                          * we were to send it and we're trying to send the refs
 488                          * atomically, abort the whole operation.
 489                          */
 490                         if (use_atomic) {
 491                                 strbuf_release(&req_buf);
 492                                 strbuf_release(&cap_buf);
 493                                 return atomic_push_failure(args, remote_refs, ref);
 494                         }
 495                         /* else fallthrough */
 496                 default:
 497                         continue;
 498                 }
 499                 if (!ref->deletion)
 500                         need_pack_data = 1;
 501
 502                 if (args->dry_run || !status_report)
 503                         ref->status = REF_STATUS_OK;
 504                 else
 505                         ref->status = REF_STATUS_EXPECTING_REPORT;
 506         }
 507
 508         /*
 509          * Finally, tell the other end!
 510          */
 511         for (ref = remote_refs; ref; ref = ref->next) {
 512                 char *old_hex, *new_hex;
 513
 514                 if (args->dry_run || push_cert_nonce)
 515                         continue;
 516
 517                 if (check_to_send_update(ref, args) < 0)
 518                         continue;
 519
 520                 old_hex = oid_to_hex(&ref->old_oid);
 521                 new_hex = oid_to_hex(&ref->new_oid);
 522                 if (!cmds_sent) {
 523                         packet_buf_write(&req_buf,
 524                                          "%s %s %s%c%s",
 525                                          old_hex, new_hex, ref->name, 0,
 526                                          cap_buf.buf);
 527                         cmds_sent = 1;
 528                 } else {
 529                         packet_buf_write(&req_buf, "%s %s %s",
 530                                          old_hex, new_hex, ref->name);
 531                 }
 532         }
 533
 534         if (use_push_options) {
 535                 struct string_list_item *item;
 536
 537                 packet_buf_flush(&req_buf);
 538                 for_each_string_list_item(item, args->push_options)
 539                         packet_buf_write(&req_buf, "%s", item->string);
 540         }
 541
 542         if (args->stateless_rpc) {
 543                 if (!args->dry_run && (cmds_sent || is_repository_shallow(the_repository))) {
 544                         packet_buf_flush(&req_buf);
 545                         send_sideband(out, -1, req_buf.buf, req_buf.len, LARGE_PACKET_MAX);
 546                 }
 547         } else {
 548                 write_or_die(out, req_buf.buf, req_buf.len);
 549                 packet_flush(out);
 550         }
 551         strbuf_release(&req_buf);
 552         strbuf_release(&cap_buf);
 553
 554         if (use_sideband && cmds_sent) {
 555                 memset(&demux, 0, sizeof(demux));
 556                 demux.proc = sideband_demux;
 557                 demux.data = fd;
 558                 demux.out = -1;
 559                 demux.isolate_sigpipe = 1;
 560                 if (start_async(&demux))
 561                         die("send-pack: unable to fork off sideband demultiplexer");
 562                 in = demux.out;
 563         }
 564
 565         packet_reader_init(&reader, in, NULL, 0,
 566                            PACKET_READ_CHOMP_NEWLINE |
 567                            PACKET_READ_DIE_ON_ERR_PACKET);
 568
 569         if (need_pack_data && cmds_sent) {
 570                 if (pack_objects(out, remote_refs, extra_have, args) < 0) {
 571                         if (args->stateless_rpc)
 572                                 close(out);
 573                         if (git_connection_is_socket(conn))
 574                                 shutdown(fd[0], SHUT_WR);
 575
 576                         /*
 577                          * Do not even bother with the return value; we know we
 578                          * are failing, and just want the error() side effects,
 579                          * as well as marking refs with their remote status (if
 580                          * we get one).
 581                          */
 582                         if (status_report)
 583                                 receive_status(&reader, remote_refs);
 584
 585                         if (use_sideband) {
 586                                 close(demux.out);
 587                                 finish_async(&demux);
 588                         }
 589                         fd[1] = -1;
 590                         return -1;
 591                 }
 592                 if (!args->stateless_rpc)
 593                         /* Closed by pack_objects() via start_command() */
 594                         fd[1] = -1;
 595         }
 596         if (args->stateless_rpc && cmds_sent)
 597                 packet_flush(out);
 598
 599         if (status_report && cmds_sent)
 600                 ret = receive_status(&reader, remote_refs);
 601         else
 602                 ret = 0;
 603         if (args->stateless_rpc)
 604                 packet_flush(out);
 605
 606         if (use_sideband && cmds_sent) {
 607                 close(demux.out);
 608                 if (finish_async(&demux)) {
 609                         error("error in sideband demultiplexer");
 610                         ret = -1;
 611                 }
 612         }
 613
 614         if (ret < 0)
 615                 return ret;
 616
 617         if (args->porcelain)
 618                 return 0;
 619
 620         for (ref = remote_refs; ref; ref = ref->next) {
 621                 switch (ref->status) {
 622                 case REF_STATUS_NONE:
 623                 case REF_STATUS_UPTODATE:
 624                 case REF_STATUS_OK:
 625                         break;
 626                 default:
 627                         return -1;
 628                 }
 629         }
 630         return 0;
 631 }