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 && !has_sha1_file(oid->hash))
  44                 return;
  45
  46         if (negative)
  47                 putc('^', fh);
  48         fputs(oid_to_hex(oid), fh);
  49         putc('\n', fh);
  50 }
  51
  52 /*
  53  * Make a pack stream and spit it out into file descriptor fd
  54  */
  55 static int pack_objects(int fd, struct ref *refs, struct oid_array *extra, struct send_pack_args *args)
  56 {
  57         /*
  58          * The child becomes pack-objects --revs; we feed
  59          * the revision parameters to it via its stdin and
  60          * let its stdout go back to the other end.
  61          */
  62         struct child_process po = CHILD_PROCESS_INIT;
  63         FILE *po_in;
  64         int i;
  65         int rc;
  66
  67         argv_array_push(&po.args, "pack-objects");
  68         argv_array_push(&po.args, "--all-progress-implied");
  69         argv_array_push(&po.args, "--revs");
  70         argv_array_push(&po.args, "--stdout");
  71         if (args->use_thin_pack)
  72                 argv_array_push(&po.args, "--thin");
  73         if (args->use_ofs_delta)
  74                 argv_array_push(&po.args, "--delta-base-offset");
  75         if (args->quiet || !args->progress)
  76                 argv_array_push(&po.args, "-q");
  77         if (args->progress)
  78                 argv_array_push(&po.args, "--progress");
  79         if (is_repository_shallow(the_repository))
  80                 argv_array_push(&po.args, "--shallow");
  81         po.in = -1;
  82         po.out = args->stateless_rpc ? -1 : fd;
  83         po.git_cmd = 1;
  84         if (start_command(&po))
  85                 die_errno("git pack-objects failed");
  86
  87         /*
  88          * We feed the pack-objects we just spawned with revision
  89          * parameters by writing to the pipe.
  90          */
  91         po_in = xfdopen(po.in, "w");
  92         for (i = 0; i < extra->nr; i++)
  93                 feed_object(&extra->oid[i], po_in, 1);
  94
  95         while (refs) {
  96                 if (!is_null_oid(&refs->old_oid))
  97                         feed_object(&refs->old_oid, po_in, 1);
  98                 if (!is_null_oid(&refs->new_oid))
  99                         feed_object(&refs->new_oid, po_in, 0);
 100                 refs = refs->next;
 101         }
 102
 103         fflush(po_in);
 104         if (ferror(po_in))
 105                 die_errno("error writing to pack-objects");
 106         fclose(po_in);
 107
 108         if (args->stateless_rpc) {
 109                 char *buf = xmalloc(LARGE_PACKET_MAX);
 110                 while (1) {
 111                         ssize_t n = xread(po.out, buf, LARGE_PACKET_MAX);
 112                         if (n <= 0)
 113                                 break;
 114                         send_sideband(fd, -1, buf, n, LARGE_PACKET_MAX);
 115                 }
 116                 free(buf);
 117                 close(po.out);
 118                 po.out = -1;
 119         }
 120
 121         rc = finish_command(&po);
 122         if (rc) {
 123                 /*
 124                  * For a normal non-zero exit, we assume pack-objects wrote
 125                  * something useful to stderr. For death by signal, though,
 126                  * we should mention it to the user. The exception is SIGPIPE
 127                  * (141), because that's a normal occurrence if the remote end
 128                  * hangs up (and we'll report that by trying to read the unpack
 129                  * status).
 130                  */
 131                 if (rc > 128 && rc != 141)
 132                         error("pack-objects died of signal %d", rc - 128);
 133                 return -1;
 134         }
 135         return 0;
 136 }
 137
 138 static int receive_unpack_status(int in)
 139 {
 140         const char *line = packet_read_line(in, NULL);
 141         if (!line)
 142                 return error(_("unexpected flush packet while reading remote unpack status"));
 143         if (!skip_prefix(line, "unpack ", &line))
 144                 return error(_("unable to parse remote unpack status: %s"), line);
 145         if (strcmp(line, "ok"))
 146                 return error(_("remote unpack failed: %s"), line);
 147         return 0;
 148 }
 149
 150 static int receive_status(int in, struct ref *refs)
 151 {
 152         struct ref *hint;
 153         int ret;
 154
 155         hint = NULL;
 156         ret = receive_unpack_status(in);
 157         while (1) {
 158                 char *refname;
 159                 char *msg;
 160                 char *line = packet_read_line(in, NULL);
 161                 if (!line)
 162                         break;
 163                 if (!starts_with(line, "ok ") && !starts_with(line, "ng ")) {
 164                         error("invalid ref status from remote: %s", line);
 165                         ret = -1;
 166                         break;
 167                 }
 168
 169                 refname = line + 3;
 170                 msg = strchr(refname, ' ');
 171                 if (msg)
 172                         *msg++ = '\0';
 173
 174                 /* first try searching at our hint, falling back to all refs */
 175                 if (hint)
 176                         hint = find_ref_by_name(hint, refname);
 177                 if (!hint)
 178                         hint = find_ref_by_name(refs, refname);
 179                 if (!hint) {
 180                         warning("remote reported status on unknown ref: %s",
 181                                         refname);
 182                         continue;
 183                 }
 184                 if (hint->status != REF_STATUS_EXPECTING_REPORT) {
 185                         warning("remote reported status on unexpected ref: %s",
 186                                         refname);
 187                         continue;
 188                 }
 189
 190                 if (line[0] == 'o' && line[1] == 'k')
 191                         hint->status = REF_STATUS_OK;
 192                 else {
 193                         hint->status = REF_STATUS_REMOTE_REJECT;
 194                         ret = -1;
 195                 }
 196                 hint->remote_status = xstrdup_or_null(msg);
 197                 /* start our next search from the next ref */
 198                 hint = hint->next;
 199         }
 200         return ret;
 201 }
 202
 203 static int sideband_demux(int in, int out, void *data)
 204 {
 205         int *fd = data, ret;
 206 #ifdef NO_PTHREADS
 207         close(fd[1]);
 208 #endif
 209         ret = recv_sideband("send-pack", fd[0], out);
 210         close(out);
 211         return ret;
 212 }
 213
 214 static int advertise_shallow_grafts_cb(const struct commit_graft *graft, void *cb)
 215 {
 216         struct strbuf *sb = cb;
 217         if (graft->nr_parent == -1)
 218                 packet_buf_write(sb, "shallow %s\n", oid_to_hex(&graft->oid));
 219         return 0;
 220 }
 221
 222 static void advertise_shallow_grafts_buf(struct strbuf *sb)
 223 {
 224         if (!is_repository_shallow(the_repository))
 225                 return;
 226         for_each_commit_graft(advertise_shallow_grafts_cb, sb);
 227 }
 228
 229 #define CHECK_REF_NO_PUSH -1
 230 #define CHECK_REF_STATUS_REJECTED -2
 231 #define CHECK_REF_UPTODATE -3
 232 static int check_to_send_update(const struct ref *ref, const struct send_pack_args *args)
 233 {
 234         if (!ref->peer_ref && !args->send_mirror)
 235                 return CHECK_REF_NO_PUSH;
 236
 237         /* Check for statuses set by set_ref_status_for_push() */
 238         switch (ref->status) {
 239         case REF_STATUS_REJECT_NONFASTFORWARD:
 240         case REF_STATUS_REJECT_ALREADY_EXISTS:
 241         case REF_STATUS_REJECT_FETCH_FIRST:
 242         case REF_STATUS_REJECT_NEEDS_FORCE:
 243         case REF_STATUS_REJECT_STALE:
 244         case REF_STATUS_REJECT_NODELETE:
 245                 return CHECK_REF_STATUS_REJECTED;
 246         case REF_STATUS_UPTODATE:
 247                 return CHECK_REF_UPTODATE;
 248         default:
 249                 return 0;
 250         }
 251 }
 252
 253 /*
 254  * the beginning of the next line, or the end of buffer.
 255  *
 256  * NEEDSWORK: perhaps move this to git-compat-util.h or somewhere and
 257  * convert many similar uses found by "git grep -A4 memchr".
 258  */
 259 static const char *next_line(const char *line, size_t len)
 260 {
 261         const char *nl = memchr(line, '\n', len);
 262         if (!nl)
 263                 return line + len; /* incomplete line */
 264         return nl + 1;
 265 }
 266
 267 static int generate_push_cert(struct strbuf *req_buf,
 268                               const struct ref *remote_refs,
 269                               struct send_pack_args *args,
 270                               const char *cap_string,
 271                               const char *push_cert_nonce)
 272 {
 273         const struct ref *ref;
 274         struct string_list_item *item;
 275         char *signing_key = xstrdup(get_signing_key());
 276         const char *cp, *np;
 277         struct strbuf cert = STRBUF_INIT;
 278         int update_seen = 0;
 279
 280         strbuf_addstr(&cert, "certificate version 0.1\n");
 281         strbuf_addf(&cert, "pusher %s ", signing_key);
 282         datestamp(&cert);
 283         strbuf_addch(&cert, '\n');
 284         if (args->url && *args->url) {
 285                 char *anon_url = transport_anonymize_url(args->url);
 286                 strbuf_addf(&cert, "pushee %s\n", anon_url);
 287                 free(anon_url);
 288         }
 289         if (push_cert_nonce[0])
 290                 strbuf_addf(&cert, "nonce %s\n", push_cert_nonce);
 291         if (args->push_options)
 292                 for_each_string_list_item(item, args->push_options)
 293                         strbuf_addf(&cert, "push-option %s\n", item->string);
 294         strbuf_addstr(&cert, "\n");
 295
 296         for (ref = remote_refs; ref; ref = ref->next) {
 297                 if (check_to_send_update(ref, args) < 0)
 298                         continue;
 299                 update_seen = 1;
 300                 strbuf_addf(&cert, "%s %s %s\n",
 301                             oid_to_hex(&ref->old_oid),
 302                             oid_to_hex(&ref->new_oid),
 303                             ref->name);
 304         }
 305         if (!update_seen)
 306                 goto free_return;
 307
 308         if (sign_buffer(&cert, &cert, signing_key))
 309                 die(_("failed to sign the push certificate"));
 310
 311         packet_buf_write(req_buf, "push-cert%c%s", 0, cap_string);
 312         for (cp = cert.buf; cp < cert.buf + cert.len; cp = np) {
 313                 np = next_line(cp, cert.buf + cert.len - cp);
 314                 packet_buf_write(req_buf,
 315                                  "%.*s", (int)(np - cp), cp);
 316         }
 317         packet_buf_write(req_buf, "push-cert-end\n");
 318
 319 free_return:
 320         free(signing_key);
 321         strbuf_release(&cert);
 322         return update_seen;
 323 }
 324
 325
 326 static int atomic_push_failure(struct send_pack_args *args,
 327                                struct ref *remote_refs,
 328                                struct ref *failing_ref)
 329 {
 330         struct ref *ref;
 331         /* Mark other refs as failed */
 332         for (ref = remote_refs; ref; ref = ref->next) {
 333                 if (!ref->peer_ref && !args->send_mirror)
 334                         continue;
 335
 336                 switch (ref->status) {
 337                 case REF_STATUS_EXPECTING_REPORT:
 338                         ref->status = REF_STATUS_ATOMIC_PUSH_FAILED;
 339                         continue;
 340                 default:
 341                         break; /* do nothing */
 342                 }
 343         }
 344         return error("atomic push failed for ref %s. status: %d\n",
 345                      failing_ref->name, failing_ref->status);
 346 }
 347
 348 #define NONCE_LEN_LIMIT 256
 349
 350 static void reject_invalid_nonce(const char *nonce, int len)
 351 {
 352         int i = 0;
 353
 354         if (NONCE_LEN_LIMIT <= len)
 355                 die("the receiving end asked to sign an invalid nonce <%.*s>",
 356                     len, nonce);
 357
 358         for (i = 0; i < len; i++) {
 359                 int ch = nonce[i] & 0xFF;
 360                 if (isalnum(ch) ||
 361                     ch == '-' || ch == '.' ||
 362                     ch == '/' || ch == '+' ||
 363                     ch == '=' || ch == '_')
 364                         continue;
 365                 die("the receiving end asked to sign an invalid nonce <%.*s>",
 366                     len, nonce);
 367         }
 368 }
 369
 370 int send_pack(struct send_pack_args *args,
 371               int fd[], struct child_process *conn,
 372               struct ref *remote_refs,
 373               struct oid_array *extra_have)
 374 {
 375         int in = fd[0];
 376         int out = fd[1];
 377         struct strbuf req_buf = STRBUF_INIT;
 378         struct strbuf cap_buf = STRBUF_INIT;
 379         struct ref *ref;
 380         int need_pack_data = 0;
 381         int allow_deleting_refs = 0;
 382         int status_report = 0;
 383         int use_sideband = 0;
 384         int quiet_supported = 0;
 385         int agent_supported = 0;
 386         int use_atomic = 0;
 387         int atomic_supported = 0;
 388         int use_push_options = 0;
 389         int push_options_supported = 0;
 390         unsigned cmds_sent = 0;
 391         int ret;
 392         struct async demux;
 393         const char *push_cert_nonce = NULL;
 394
 395         /* Does the other end support the reporting? */
 396         if (server_supports("report-status"))
 397                 status_report = 1;
 398         if (server_supports("delete-refs"))
 399                 allow_deleting_refs = 1;
 400         if (server_supports("ofs-delta"))
 401                 args->use_ofs_delta = 1;
 402         if (server_supports("side-band-64k"))
 403                 use_sideband = 1;
 404         if (server_supports("quiet"))
 405                 quiet_supported = 1;
 406         if (server_supports("agent"))
 407                 agent_supported = 1;
 408         if (server_supports("no-thin"))
 409                 args->use_thin_pack = 0;
 410         if (server_supports("atomic"))
 411                 atomic_supported = 1;
 412         if (server_supports("push-options"))
 413                 push_options_supported = 1;
 414
 415         if (args->push_cert != SEND_PACK_PUSH_CERT_NEVER) {
 416                 int len;
 417                 push_cert_nonce = server_feature_value("push-cert", &len);
 418                 if (push_cert_nonce) {
 419                         reject_invalid_nonce(push_cert_nonce, len);
 420                         push_cert_nonce = xmemdupz(push_cert_nonce, len);
 421                 } else if (args->push_cert == SEND_PACK_PUSH_CERT_ALWAYS) {
 422                         die(_("the receiving end does not support --signed push"));
 423                 } else if (args->push_cert == SEND_PACK_PUSH_CERT_IF_ASKED) {
 424                         warning(_("not sending a push certificate since the"
 425                                   " receiving end does not support --signed"
 426                                   " push"));
 427                 }
 428         }
 429
 430         if (!remote_refs) {
 431                 fprintf(stderr, "No refs in common and none specified; doing nothing.\n"
 432                         "Perhaps you should specify a branch such as 'master'.\n");
 433                 return 0;
 434         }
 435         if (args->atomic && !atomic_supported)
 436                 die(_("the receiving end does not support --atomic push"));
 437
 438         use_atomic = atomic_supported && args->atomic;
 439
 440         if (args->push_options && !push_options_supported)
 441                 die(_("the receiving end does not support push options"));
 442
 443         use_push_options = push_options_supported && args->push_options;
 444
 445         if (status_report)
 446                 strbuf_addstr(&cap_buf, " report-status");
 447         if (use_sideband)
 448                 strbuf_addstr(&cap_buf, " side-band-64k");
 449         if (quiet_supported && (args->quiet || !args->progress))
 450                 strbuf_addstr(&cap_buf, " quiet");
 451         if (use_atomic)
 452                 strbuf_addstr(&cap_buf, " atomic");
 453         if (use_push_options)
 454                 strbuf_addstr(&cap_buf, " push-options");
 455         if (agent_supported)
 456                 strbuf_addf(&cap_buf, " agent=%s", git_user_agent_sanitized());
 457
 458         /*
 459          * NEEDSWORK: why does delete-refs have to be so specific to
 460          * send-pack machinery that set_ref_status_for_push() cannot
 461          * set this bit for us???
 462          */
 463         for (ref = remote_refs; ref; ref = ref->next)
 464                 if (ref->deletion && !allow_deleting_refs)
 465                         ref->status = REF_STATUS_REJECT_NODELETE;
 466
 467         if (!args->dry_run)
 468                 advertise_shallow_grafts_buf(&req_buf);
 469
 470         if (!args->dry_run && push_cert_nonce)
 471                 cmds_sent = generate_push_cert(&req_buf, remote_refs, args,
 472                                                cap_buf.buf, push_cert_nonce);
 473
 474         /*
 475          * Clear the status for each ref and see if we need to send
 476          * the pack data.
 477          */
 478         for (ref = remote_refs; ref; ref = ref->next) {
 479                 switch (check_to_send_update(ref, args)) {
 480                 case 0: /* no error */
 481                         break;
 482                 case CHECK_REF_STATUS_REJECTED:
 483                         /*
 484                          * When we know the server would reject a ref update if
 485                          * we were to send it and we're trying to send the refs
 486                          * atomically, abort the whole operation.
 487                          */
 488                         if (use_atomic) {
 489                                 strbuf_release(&req_buf);
 490                                 strbuf_release(&cap_buf);
 491                                 return atomic_push_failure(args, remote_refs, ref);
 492                         }
 493                         /* else fallthrough */
 494                 default:
 495                         continue;
 496                 }
 497                 if (!ref->deletion)
 498                         need_pack_data = 1;
 499
 500                 if (args->dry_run || !status_report)
 501                         ref->status = REF_STATUS_OK;
 502                 else
 503                         ref->status = REF_STATUS_EXPECTING_REPORT;
 504         }
 505
 506         /*
 507          * Finally, tell the other end!
 508          */
 509         for (ref = remote_refs; ref; ref = ref->next) {
 510                 char *old_hex, *new_hex;
 511
 512                 if (args->dry_run || push_cert_nonce)
 513                         continue;
 514
 515                 if (check_to_send_update(ref, args) < 0)
 516                         continue;
 517
 518                 old_hex = oid_to_hex(&ref->old_oid);
 519                 new_hex = oid_to_hex(&ref->new_oid);
 520                 if (!cmds_sent) {
 521                         packet_buf_write(&req_buf,
 522                                          "%s %s %s%c%s",
 523                                          old_hex, new_hex, ref->name, 0,
 524                                          cap_buf.buf);
 525                         cmds_sent = 1;
 526                 } else {
 527                         packet_buf_write(&req_buf, "%s %s %s",
 528                                          old_hex, new_hex, ref->name);
 529                 }
 530         }
 531
 532         if (use_push_options) {
 533                 struct string_list_item *item;
 534
 535                 packet_buf_flush(&req_buf);
 536                 for_each_string_list_item(item, args->push_options)
 537                         packet_buf_write(&req_buf, "%s", item->string);
 538         }
 539
 540         if (args->stateless_rpc) {
 541                 if (!args->dry_run && (cmds_sent || is_repository_shallow(the_repository))) {
 542                         packet_buf_flush(&req_buf);
 543                         send_sideband(out, -1, req_buf.buf, req_buf.len, LARGE_PACKET_MAX);
 544                 }
 545         } else {
 546                 write_or_die(out, req_buf.buf, req_buf.len);
 547                 packet_flush(out);
 548         }
 549         strbuf_release(&req_buf);
 550         strbuf_release(&cap_buf);
 551
 552         if (use_sideband && cmds_sent) {
 553                 memset(&demux, 0, sizeof(demux));
 554                 demux.proc = sideband_demux;
 555                 demux.data = fd;
 556                 demux.out = -1;
 557                 demux.isolate_sigpipe = 1;
 558                 if (start_async(&demux))
 559                         die("send-pack: unable to fork off sideband demultiplexer");
 560                 in = demux.out;
 561         }
 562
 563         if (need_pack_data && cmds_sent) {
 564                 if (pack_objects(out, remote_refs, extra_have, args) < 0) {
 565                         for (ref = remote_refs; ref; ref = ref->next)
 566                                 ref->status = REF_STATUS_NONE;
 567                         if (args->stateless_rpc)
 568                                 close(out);
 569                         if (git_connection_is_socket(conn))
 570                                 shutdown(fd[0], SHUT_WR);
 571
 572                         /*
 573                          * Do not even bother with the return value; we know we
 574                          * are failing, and just want the error() side effects.
 575                          */
 576                         if (status_report)
 577                                 receive_unpack_status(in);
 578
 579                         if (use_sideband) {
 580                                 close(demux.out);
 581                                 finish_async(&demux);
 582                         }
 583                         fd[1] = -1;
 584                         return -1;
 585                 }
 586                 if (!args->stateless_rpc)
 587                         /* Closed by pack_objects() via start_command() */
 588                         fd[1] = -1;
 589         }
 590         if (args->stateless_rpc && cmds_sent)
 591                 packet_flush(out);
 592
 593         if (status_report && cmds_sent)
 594                 ret = receive_status(in, remote_refs);
 595         else
 596                 ret = 0;
 597         if (args->stateless_rpc)
 598                 packet_flush(out);
 599
 600         if (use_sideband && cmds_sent) {
 601                 close(demux.out);
 602                 if (finish_async(&demux)) {
 603                         error("error in sideband demultiplexer");
 604                         ret = -1;
 605                 }
 606         }
 607
 608         if (ret < 0)
 609                 return ret;
 610
 611         if (args->porcelain)
 612                 return 0;
 613
 614         for (ref = remote_refs; ref; ref = ref->next) {
 615                 switch (ref->status) {
 616                 case REF_STATUS_NONE:
 617                 case REF_STATUS_UPTODATE:
 618                 case REF_STATUS_OK:
 619                         break;
 620                 default:
 621                         return -1;
 622                 }
 623         }
 624         return 0;
 625 }