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