send-pack.c

   1 #include "builtin.h"
   2 #include "commit.h"
   3 #include "refs.h"
   4 #include "pkt-line.h"
   5 #include "sideband.h"
   6 #include "run-command.h"
   7 #include "remote.h"
   8 #include "connect.h"
   9 #include "send-pack.h"
  10 #include "quote.h"
  11 #include "transport.h"
  12 #include "version.h"
  13 #include "sha1-array.h"
  14 #include "gpg-interface.h"
  15 #include "cache.h"
  16
  17 int option_parse_push_signed(const struct option *opt,
  18                              const char *arg, int unset)
  19 {
  20         if (unset) {
  21                 *(int *)(opt->value) = SEND_PACK_PUSH_CERT_NEVER;
  22                 return 0;
  23         }
  24         switch (git_parse_maybe_bool(arg)) {
  25         case 1:
  26                 *(int *)(opt->value) = SEND_PACK_PUSH_CERT_ALWAYS;
  27                 return 0;
  28         case 0:
  29                 *(int *)(opt->value) = SEND_PACK_PUSH_CERT_NEVER;
  30                 return 0;
  31         }
  32         if (!strcasecmp("if-asked", arg)) {
  33                 *(int *)(opt->value) = SEND_PACK_PUSH_CERT_IF_ASKED;
  34                 return 0;
  35         }
  36         die("bad %s argument: %s", opt->long_name, arg);
  37 }
  38
  39 static void feed_object(const unsigned char *sha1, FILE *fh, int negative)
  40 {
  41         if (negative && !has_sha1_file(sha1))
  42                 return;
  43
  44         if (negative)
  45                 putc('^', fh);
  46         fputs(sha1_to_hex(sha1), fh);
  47         putc('\n', fh);
  48 }
  49
  50 /*
  51  * Make a pack stream and spit it out into file descriptor fd
  52  */
  53 static int pack_objects(int fd, struct ref *refs, struct sha1_array *extra, struct send_pack_args *args)
  54 {
  55         /*
  56          * The child becomes pack-objects --revs; we feed
  57          * the revision parameters to it via its stdin and
  58          * let its stdout go back to the other end.
  59          */
  60         const char *argv[] = {
  61                 "pack-objects",
  62                 "--all-progress-implied",
  63                 "--revs",
  64                 "--stdout",
  65                 NULL,
  66                 NULL,
  67                 NULL,
  68                 NULL,
  69                 NULL,
  70                 NULL,
  71         };
  72         struct child_process po = CHILD_PROCESS_INIT;
  73         FILE *po_in;
  74         int i;
  75
  76         i = 4;
  77         if (args->use_thin_pack)
  78                 argv[i++] = "--thin";
  79         if (args->use_ofs_delta)
  80                 argv[i++] = "--delta-base-offset";
  81         if (args->quiet || !args->progress)
  82                 argv[i++] = "-q";
  83         if (args->progress)
  84                 argv[i++] = "--progress";
  85         if (is_repository_shallow())
  86                 argv[i++] = "--shallow";
  87         po.argv = argv;
  88         po.in = -1;
  89         po.out = args->stateless_rpc ? -1 : fd;
  90         po.git_cmd = 1;
  91         if (start_command(&po))
  92                 die_errno("git pack-objects failed");
  93
  94         /*
  95          * We feed the pack-objects we just spawned with revision
  96          * parameters by writing to the pipe.
  97          */
  98         po_in = xfdopen(po.in, "w");
  99         for (i = 0; i < extra->nr; i++)
 100                 feed_object(extra->sha1[i], po_in, 1);
 101
 102         while (refs) {
 103                 if (!is_null_oid(&refs->old_oid))
 104                         feed_object(refs->old_oid.hash, po_in, 1);
 105                 if (!is_null_oid(&refs->new_oid))
 106                         feed_object(refs->new_oid.hash, po_in, 0);
 107                 refs = refs->next;
 108         }
 109
 110         fflush(po_in);
 111         if (ferror(po_in))
 112                 die_errno("error writing to pack-objects");
 113         fclose(po_in);
 114
 115         if (args->stateless_rpc) {
 116                 char *buf = xmalloc(LARGE_PACKET_MAX);
 117                 while (1) {
 118                         ssize_t n = xread(po.out, buf, LARGE_PACKET_MAX);
 119                         if (n <= 0)
 120                                 break;
 121                         send_sideband(fd, -1, buf, n, LARGE_PACKET_MAX);
 122                 }
 123                 free(buf);
 124                 close(po.out);
 125                 po.out = -1;
 126         }
 127
 128         if (finish_command(&po))
 129                 return -1;
 130         return 0;
 131 }
 132
 133 static int receive_status(int in, struct ref *refs)
 134 {
 135         struct ref *hint;
 136         int ret = 0;
 137         char *line = packet_read_line(in, NULL);
 138         if (!starts_with(line, "unpack "))
 139                 return error("did not receive remote status");
 140         if (strcmp(line, "unpack ok")) {
 141                 error("unpack failed: %s", line + 7);
 142                 ret = -1;
 143         }
 144         hint = NULL;
 145         while (1) {
 146                 char *refname;
 147                 char *msg;
 148                 line = packet_read_line(in, NULL);
 149                 if (!line)
 150                         break;
 151                 if (!starts_with(line, "ok ") && !starts_with(line, "ng ")) {
 152                         error("invalid ref status from remote: %s", line);
 153                         ret = -1;
 154                         break;
 155                 }
 156
 157                 refname = line + 3;
 158                 msg = strchr(refname, ' ');
 159                 if (msg)
 160                         *msg++ = '\0';
 161
 162                 /* first try searching at our hint, falling back to all refs */
 163                 if (hint)
 164                         hint = find_ref_by_name(hint, refname);
 165                 if (!hint)
 166                         hint = find_ref_by_name(refs, refname);
 167                 if (!hint) {
 168                         warning("remote reported status on unknown ref: %s",
 169                                         refname);
 170                         continue;
 171                 }
 172                 if (hint->status != REF_STATUS_EXPECTING_REPORT) {
 173                         warning("remote reported status on unexpected ref: %s",
 174                                         refname);
 175                         continue;
 176                 }
 177
 178                 if (line[0] == 'o' && line[1] == 'k')
 179                         hint->status = REF_STATUS_OK;
 180                 else {
 181                         hint->status = REF_STATUS_REMOTE_REJECT;
 182                         ret = -1;
 183                 }
 184                 hint->remote_status = xstrdup_or_null(msg);
 185                 /* start our next search from the next ref */
 186                 hint = hint->next;
 187         }
 188         return ret;
 189 }
 190
 191 static int sideband_demux(int in, int out, void *data)
 192 {
 193         int *fd = data, ret;
 194 #ifdef NO_PTHREADS
 195         close(fd[1]);
 196 #endif
 197         ret = recv_sideband("send-pack", fd[0], out);
 198         close(out);
 199         return ret;
 200 }
 201
 202 static int advertise_shallow_grafts_cb(const struct commit_graft *graft, void *cb)
 203 {
 204         struct strbuf *sb = cb;
 205         if (graft->nr_parent == -1)
 206                 packet_buf_write(sb, "shallow %s\n", oid_to_hex(&graft->oid));
 207         return 0;
 208 }
 209
 210 static void advertise_shallow_grafts_buf(struct strbuf *sb)
 211 {
 212         if (!is_repository_shallow())
 213                 return;
 214         for_each_commit_graft(advertise_shallow_grafts_cb, sb);
 215 }
 216
 217 #define CHECK_REF_NO_PUSH -1
 218 #define CHECK_REF_STATUS_REJECTED -2
 219 #define CHECK_REF_UPTODATE -3
 220 static int check_to_send_update(const struct ref *ref, const struct send_pack_args *args)
 221 {
 222         if (!ref->peer_ref && !args->send_mirror)
 223                 return CHECK_REF_NO_PUSH;
 224
 225         /* Check for statuses set by set_ref_status_for_push() */
 226         switch (ref->status) {
 227         case REF_STATUS_REJECT_NONFASTFORWARD:
 228         case REF_STATUS_REJECT_ALREADY_EXISTS:
 229         case REF_STATUS_REJECT_FETCH_FIRST:
 230         case REF_STATUS_REJECT_NEEDS_FORCE:
 231         case REF_STATUS_REJECT_STALE:
 232         case REF_STATUS_REJECT_NODELETE:
 233                 return CHECK_REF_STATUS_REJECTED;
 234         case REF_STATUS_UPTODATE:
 235                 return CHECK_REF_UPTODATE;
 236         default:
 237                 return 0;
 238         }
 239 }
 240
 241 /*
 242  * the beginning of the next line, or the end of buffer.
 243  *
 244  * NEEDSWORK: perhaps move this to git-compat-util.h or somewhere and
 245  * convert many similar uses found by "git grep -A4 memchr".
 246  */
 247 static const char *next_line(const char *line, size_t len)
 248 {
 249         const char *nl = memchr(line, '\n', len);
 250         if (!nl)
 251                 return line + len; /* incomplete line */
 252         return nl + 1;
 253 }
 254
 255 static int generate_push_cert(struct strbuf *req_buf,
 256                               const struct ref *remote_refs,
 257                               struct send_pack_args *args,
 258                               const char *cap_string,
 259                               const char *push_cert_nonce)
 260 {
 261         const struct ref *ref;
 262         struct string_list_item *item;
 263         char *signing_key = xstrdup(get_signing_key());
 264         const char *cp, *np;
 265         struct strbuf cert = STRBUF_INIT;
 266         int update_seen = 0;
 267
 268         strbuf_addstr(&cert, "certificate version 0.1\n");
 269         strbuf_addf(&cert, "pusher %s ", signing_key);
 270         datestamp(&cert);
 271         strbuf_addch(&cert, '\n');
 272         if (args->url && *args->url) {
 273                 char *anon_url = transport_anonymize_url(args->url);
 274                 strbuf_addf(&cert, "pushee %s\n", anon_url);
 275                 free(anon_url);
 276         }
 277         if (push_cert_nonce[0])
 278                 strbuf_addf(&cert, "nonce %s\n", push_cert_nonce);
 279         if (args->push_options)
 280                 for_each_string_list_item(item, args->push_options)
 281                         strbuf_addf(&cert, "push-option %s\n", item->string);
 282         strbuf_addstr(&cert, "\n");
 283
 284         for (ref = remote_refs; ref; ref = ref->next) {
 285                 if (check_to_send_update(ref, args) < 0)
 286                         continue;
 287                 update_seen = 1;
 288                 strbuf_addf(&cert, "%s %s %s\n",
 289                             oid_to_hex(&ref->old_oid),
 290                             oid_to_hex(&ref->new_oid),
 291                             ref->name);
 292         }
 293         if (!update_seen)
 294                 goto free_return;
 295
 296         if (sign_buffer(&cert, &cert, signing_key))
 297                 die(_("failed to sign the push certificate"));
 298
 299         packet_buf_write(req_buf, "push-cert%c%s", 0, cap_string);
 300         for (cp = cert.buf; cp < cert.buf + cert.len; cp = np) {
 301                 np = next_line(cp, cert.buf + cert.len - cp);
 302                 packet_buf_write(req_buf,
 303                                  "%.*s", (int)(np - cp), cp);
 304         }
 305         packet_buf_write(req_buf, "push-cert-end\n");
 306
 307 free_return:
 308         free(signing_key);
 309         strbuf_release(&cert);
 310         return update_seen;
 311 }
 312
 313
 314 static int atomic_push_failure(struct send_pack_args *args,
 315                                struct ref *remote_refs,
 316                                struct ref *failing_ref)
 317 {
 318         struct ref *ref;
 319         /* Mark other refs as failed */
 320         for (ref = remote_refs; ref; ref = ref->next) {
 321                 if (!ref->peer_ref && !args->send_mirror)
 322                         continue;
 323
 324                 switch (ref->status) {
 325                 case REF_STATUS_EXPECTING_REPORT:
 326                         ref->status = REF_STATUS_ATOMIC_PUSH_FAILED;
 327                         continue;
 328                 default:
 329                         break; /* do nothing */
 330                 }
 331         }
 332         return error("atomic push failed for ref %s. status: %d\n",
 333                      failing_ref->name, failing_ref->status);
 334 }
 335
 336 #define NONCE_LEN_LIMIT 256
 337
 338 static void reject_invalid_nonce(const char *nonce, int len)
 339 {
 340         int i = 0;
 341
 342         if (NONCE_LEN_LIMIT <= len)
 343                 die("the receiving end asked to sign an invalid nonce <%.*s>",
 344                     len, nonce);
 345
 346         for (i = 0; i < len; i++) {
 347                 int ch = nonce[i] & 0xFF;
 348                 if (isalnum(ch) ||
 349                     ch == '-' || ch == '.' ||
 350                     ch == '/' || ch == '+' ||
 351                     ch == '=' || ch == '_')
 352                         continue;
 353                 die("the receiving end asked to sign an invalid nonce <%.*s>",
 354                     len, nonce);
 355         }
 356 }
 357
 358 int send_pack(struct send_pack_args *args,
 359               int fd[], struct child_process *conn,
 360               struct ref *remote_refs,
 361               struct sha1_array *extra_have)
 362 {
 363         int in = fd[0];
 364         int out = fd[1];
 365         struct strbuf req_buf = STRBUF_INIT;
 366         struct strbuf cap_buf = STRBUF_INIT;
 367         struct ref *ref;
 368         int need_pack_data = 0;
 369         int allow_deleting_refs = 0;
 370         int status_report = 0;
 371         int use_sideband = 0;
 372         int quiet_supported = 0;
 373         int agent_supported = 0;
 374         int use_atomic = 0;
 375         int atomic_supported = 0;
 376         int use_push_options = 0;
 377         int push_options_supported = 0;
 378         unsigned cmds_sent = 0;
 379         int ret;
 380         struct async demux;
 381         const char *push_cert_nonce = NULL;
 382
 383         /* Does the other end support the reporting? */
 384         if (server_supports("report-status"))
 385                 status_report = 1;
 386         if (server_supports("delete-refs"))
 387                 allow_deleting_refs = 1;
 388         if (server_supports("ofs-delta"))
 389                 args->use_ofs_delta = 1;
 390         if (server_supports("side-band-64k"))
 391                 use_sideband = 1;
 392         if (server_supports("quiet"))
 393                 quiet_supported = 1;
 394         if (server_supports("agent"))
 395                 agent_supported = 1;
 396         if (server_supports("no-thin"))
 397                 args->use_thin_pack = 0;
 398         if (server_supports("atomic"))
 399                 atomic_supported = 1;
 400         if (server_supports("push-options"))
 401                 push_options_supported = 1;
 402
 403         if (args->push_cert != SEND_PACK_PUSH_CERT_NEVER) {
 404                 int len;
 405                 push_cert_nonce = server_feature_value("push-cert", &len);
 406                 if (push_cert_nonce) {
 407                         reject_invalid_nonce(push_cert_nonce, len);
 408                         push_cert_nonce = xmemdupz(push_cert_nonce, len);
 409                 } else if (args->push_cert == SEND_PACK_PUSH_CERT_ALWAYS) {
 410                         die(_("the receiving end does not support --signed push"));
 411                 } else if (args->push_cert == SEND_PACK_PUSH_CERT_IF_ASKED) {
 412                         warning(_("not sending a push certificate since the"
 413                                   " receiving end does not support --signed"
 414                                   " push"));
 415                 }
 416         }
 417
 418         if (!remote_refs) {
 419                 fprintf(stderr, "No refs in common and none specified; doing nothing.\n"
 420                         "Perhaps you should specify a branch such as 'master'.\n");
 421                 return 0;
 422         }
 423         if (args->atomic && !atomic_supported)
 424                 die(_("the receiving end does not support --atomic push"));
 425
 426         use_atomic = atomic_supported && args->atomic;
 427
 428         if (args->push_options && !push_options_supported)
 429                 die(_("the receiving end does not support push options"));
 430
 431         use_push_options = push_options_supported && args->push_options;
 432
 433         if (status_report)
 434                 strbuf_addstr(&cap_buf, " report-status");
 435         if (use_sideband)
 436                 strbuf_addstr(&cap_buf, " side-band-64k");
 437         if (quiet_supported && (args->quiet || !args->progress))
 438                 strbuf_addstr(&cap_buf, " quiet");
 439         if (use_atomic)
 440                 strbuf_addstr(&cap_buf, " atomic");
 441         if (use_push_options)
 442                 strbuf_addstr(&cap_buf, " push-options");
 443         if (agent_supported)
 444                 strbuf_addf(&cap_buf, " agent=%s", git_user_agent_sanitized());
 445
 446         /*
 447          * NEEDSWORK: why does delete-refs have to be so specific to
 448          * send-pack machinery that set_ref_status_for_push() cannot
 449          * set this bit for us???
 450          */
 451         for (ref = remote_refs; ref; ref = ref->next)
 452                 if (ref->deletion && !allow_deleting_refs)
 453                         ref->status = REF_STATUS_REJECT_NODELETE;
 454
 455         if (!args->dry_run)
 456                 advertise_shallow_grafts_buf(&req_buf);
 457
 458         if (!args->dry_run && push_cert_nonce)
 459                 cmds_sent = generate_push_cert(&req_buf, remote_refs, args,
 460                                                cap_buf.buf, push_cert_nonce);
 461
 462         /*
 463          * Clear the status for each ref and see if we need to send
 464          * the pack data.
 465          */
 466         for (ref = remote_refs; ref; ref = ref->next) {
 467                 switch (check_to_send_update(ref, args)) {
 468                 case 0: /* no error */
 469                         break;
 470                 case CHECK_REF_STATUS_REJECTED:
 471                         /*
 472                          * When we know the server would reject a ref update if
 473                          * we were to send it and we're trying to send the refs
 474                          * atomically, abort the whole operation.
 475                          */
 476                         if (use_atomic)
 477                                 return atomic_push_failure(args, remote_refs, ref);
 478                         /* Fallthrough for non atomic case. */
 479                 default:
 480                         continue;
 481                 }
 482                 if (!ref->deletion)
 483                         need_pack_data = 1;
 484
 485                 if (args->dry_run || !status_report)
 486                         ref->status = REF_STATUS_OK;
 487                 else
 488                         ref->status = REF_STATUS_EXPECTING_REPORT;
 489         }
 490
 491         /*
 492          * Finally, tell the other end!
 493          */
 494         for (ref = remote_refs; ref; ref = ref->next) {
 495                 char *old_hex, *new_hex;
 496
 497                 if (args->dry_run || push_cert_nonce)
 498                         continue;
 499
 500                 if (check_to_send_update(ref, args) < 0)
 501                         continue;
 502
 503                 old_hex = oid_to_hex(&ref->old_oid);
 504                 new_hex = oid_to_hex(&ref->new_oid);
 505                 if (!cmds_sent) {
 506                         packet_buf_write(&req_buf,
 507                                          "%s %s %s%c%s",
 508                                          old_hex, new_hex, ref->name, 0,
 509                                          cap_buf.buf);
 510                         cmds_sent = 1;
 511                 } else {
 512                         packet_buf_write(&req_buf, "%s %s %s",
 513                                          old_hex, new_hex, ref->name);
 514                 }
 515         }
 516
 517         if (use_push_options) {
 518                 struct string_list_item *item;
 519
 520                 packet_buf_flush(&req_buf);
 521                 for_each_string_list_item(item, args->push_options)
 522                         packet_buf_write(&req_buf, "%s", item->string);
 523         }
 524
 525         if (args->stateless_rpc) {
 526                 if (!args->dry_run && (cmds_sent || is_repository_shallow())) {
 527                         packet_buf_flush(&req_buf);
 528                         send_sideband(out, -1, req_buf.buf, req_buf.len, LARGE_PACKET_MAX);
 529                 }
 530         } else {
 531                 write_or_die(out, req_buf.buf, req_buf.len);
 532                 packet_flush(out);
 533         }
 534         strbuf_release(&req_buf);
 535         strbuf_release(&cap_buf);
 536
 537         if (use_sideband && cmds_sent) {
 538                 memset(&demux, 0, sizeof(demux));
 539                 demux.proc = sideband_demux;
 540                 demux.data = fd;
 541                 demux.out = -1;
 542                 demux.isolate_sigpipe = 1;
 543                 if (start_async(&demux))
 544                         die("send-pack: unable to fork off sideband demultiplexer");
 545                 in = demux.out;
 546         }
 547
 548         if (need_pack_data && cmds_sent) {
 549                 if (pack_objects(out, remote_refs, extra_have, args) < 0) {
 550                         for (ref = remote_refs; ref; ref = ref->next)
 551                                 ref->status = REF_STATUS_NONE;
 552                         if (args->stateless_rpc)
 553                                 close(out);
 554                         if (git_connection_is_socket(conn))
 555                                 shutdown(fd[0], SHUT_WR);
 556                         if (use_sideband) {
 557                                 close(demux.out);
 558                                 finish_async(&demux);
 559                         }
 560                         fd[1] = -1;
 561                         return -1;
 562                 }
 563                 if (!args->stateless_rpc)
 564                         /* Closed by pack_objects() via start_command() */
 565                         fd[1] = -1;
 566         }
 567         if (args->stateless_rpc && cmds_sent)
 568                 packet_flush(out);
 569
 570         if (status_report && cmds_sent)
 571                 ret = receive_status(in, remote_refs);
 572         else
 573                 ret = 0;
 574         if (args->stateless_rpc)
 575                 packet_flush(out);
 576
 577         if (use_sideband && cmds_sent) {
 578                 close(demux.out);
 579                 if (finish_async(&demux)) {
 580                         error("error in sideband demultiplexer");
 581                         ret = -1;
 582                 }
 583         }
 584
 585         if (ret < 0)
 586                 return ret;
 587
 588         if (args->porcelain)
 589                 return 0;
 590
 591         for (ref = remote_refs; ref; ref = ref->next) {
 592                 switch (ref->status) {
 593                 case REF_STATUS_NONE:
 594                 case REF_STATUS_UPTODATE:
 595                 case REF_STATUS_OK:
 596                         break;
 597                 default:
 598                         return -1;
 599                 }
 600         }
 601         return 0;
 602 }