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                 if (msg)
 185                         hint->remote_status = xstrdup(msg);
 186                 /* start our next search from the next ref */
 187                 hint = hint->next;
 188         }
 189         return ret;
 190 }
 191
 192 static int sideband_demux(int in, int out, void *data)
 193 {
 194         int *fd = data, ret;
 195 #ifdef NO_PTHREADS
 196         close(fd[1]);
 197 #endif
 198         ret = recv_sideband("send-pack", fd[0], out);
 199         close(out);
 200         return ret;
 201 }
 202
 203 static int advertise_shallow_grafts_cb(const struct commit_graft *graft, void *cb)
 204 {
 205         struct strbuf *sb = cb;
 206         if (graft->nr_parent == -1)
 207                 packet_buf_write(sb, "shallow %s\n", oid_to_hex(&graft->oid));
 208         return 0;
 209 }
 210
 211 static void advertise_shallow_grafts_buf(struct strbuf *sb)
 212 {
 213         if (!is_repository_shallow())
 214                 return;
 215         for_each_commit_graft(advertise_shallow_grafts_cb, sb);
 216 }
 217
 218 #define CHECK_REF_NO_PUSH -1
 219 #define CHECK_REF_STATUS_REJECTED -2
 220 #define CHECK_REF_UPTODATE -3
 221 static int check_to_send_update(const struct ref *ref, const struct send_pack_args *args)
 222 {
 223         if (!ref->peer_ref && !args->send_mirror)
 224                 return CHECK_REF_NO_PUSH;
 225
 226         /* Check for statuses set by set_ref_status_for_push() */
 227         switch (ref->status) {
 228         case REF_STATUS_REJECT_NONFASTFORWARD:
 229         case REF_STATUS_REJECT_ALREADY_EXISTS:
 230         case REF_STATUS_REJECT_FETCH_FIRST:
 231         case REF_STATUS_REJECT_NEEDS_FORCE:
 232         case REF_STATUS_REJECT_STALE:
 233         case REF_STATUS_REJECT_NODELETE:
 234                 return CHECK_REF_STATUS_REJECTED;
 235         case REF_STATUS_UPTODATE:
 236                 return CHECK_REF_UPTODATE;
 237         default:
 238                 return 0;
 239         }
 240 }
 241
 242 /*
 243  * the beginning of the next line, or the end of buffer.
 244  *
 245  * NEEDSWORK: perhaps move this to git-compat-util.h or somewhere and
 246  * convert many similar uses found by "git grep -A4 memchr".
 247  */
 248 static const char *next_line(const char *line, size_t len)
 249 {
 250         const char *nl = memchr(line, '\n', len);
 251         if (!nl)
 252                 return line + len; /* incomplete line */
 253         return nl + 1;
 254 }
 255
 256 static int generate_push_cert(struct strbuf *req_buf,
 257                               const struct ref *remote_refs,
 258                               struct send_pack_args *args,
 259                               const char *cap_string,
 260                               const char *push_cert_nonce)
 261 {
 262         const struct ref *ref;
 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         strbuf_addstr(&cert, "\n");
 280
 281         for (ref = remote_refs; ref; ref = ref->next) {
 282                 if (check_to_send_update(ref, args) < 0)
 283                         continue;
 284                 update_seen = 1;
 285                 strbuf_addf(&cert, "%s %s %s\n",
 286                             oid_to_hex(&ref->old_oid),
 287                             oid_to_hex(&ref->new_oid),
 288                             ref->name);
 289         }
 290         if (!update_seen)
 291                 goto free_return;
 292
 293         if (sign_buffer(&cert, &cert, signing_key))
 294                 die(_("failed to sign the push certificate"));
 295
 296         packet_buf_write(req_buf, "push-cert%c%s", 0, cap_string);
 297         for (cp = cert.buf; cp < cert.buf + cert.len; cp = np) {
 298                 np = next_line(cp, cert.buf + cert.len - cp);
 299                 packet_buf_write(req_buf,
 300                                  "%.*s", (int)(np - cp), cp);
 301         }
 302         packet_buf_write(req_buf, "push-cert-end\n");
 303
 304 free_return:
 305         free(signing_key);
 306         strbuf_release(&cert);
 307         return update_seen;
 308 }
 309
 310
 311 static int atomic_push_failure(struct send_pack_args *args,
 312                                struct ref *remote_refs,
 313                                struct ref *failing_ref)
 314 {
 315         struct ref *ref;
 316         /* Mark other refs as failed */
 317         for (ref = remote_refs; ref; ref = ref->next) {
 318                 if (!ref->peer_ref && !args->send_mirror)
 319                         continue;
 320
 321                 switch (ref->status) {
 322                 case REF_STATUS_EXPECTING_REPORT:
 323                         ref->status = REF_STATUS_ATOMIC_PUSH_FAILED;
 324                         continue;
 325                 default:
 326                         break; /* do nothing */
 327                 }
 328         }
 329         return error("atomic push failed for ref %s. status: %d\n",
 330                      failing_ref->name, failing_ref->status);
 331 }
 332
 333 #define NONCE_LEN_LIMIT 256
 334
 335 static void reject_invalid_nonce(const char *nonce, int len)
 336 {
 337         int i = 0;
 338
 339         if (NONCE_LEN_LIMIT <= len)
 340                 die("the receiving end asked to sign an invalid nonce <%.*s>",
 341                     len, nonce);
 342
 343         for (i = 0; i < len; i++) {
 344                 int ch = nonce[i] & 0xFF;
 345                 if (isalnum(ch) ||
 346                     ch == '-' || ch == '.' ||
 347                     ch == '/' || ch == '+' ||
 348                     ch == '=' || ch == '_')
 349                         continue;
 350                 die("the receiving end asked to sign an invalid nonce <%.*s>",
 351                     len, nonce);
 352         }
 353 }
 354
 355 int send_pack(struct send_pack_args *args,
 356               int fd[], struct child_process *conn,
 357               struct ref *remote_refs,
 358               struct sha1_array *extra_have)
 359 {
 360         int in = fd[0];
 361         int out = fd[1];
 362         struct strbuf req_buf = STRBUF_INIT;
 363         struct strbuf cap_buf = STRBUF_INIT;
 364         struct ref *ref;
 365         int need_pack_data = 0;
 366         int allow_deleting_refs = 0;
 367         int status_report = 0;
 368         int use_sideband = 0;
 369         int quiet_supported = 0;
 370         int agent_supported = 0;
 371         int use_atomic = 0;
 372         int atomic_supported = 0;
 373         unsigned cmds_sent = 0;
 374         int ret;
 375         struct async demux;
 376         const char *push_cert_nonce = NULL;
 377
 378         /* Does the other end support the reporting? */
 379         if (server_supports("report-status"))
 380                 status_report = 1;
 381         if (server_supports("delete-refs"))
 382                 allow_deleting_refs = 1;
 383         if (server_supports("ofs-delta"))
 384                 args->use_ofs_delta = 1;
 385         if (server_supports("side-band-64k"))
 386                 use_sideband = 1;
 387         if (server_supports("quiet"))
 388                 quiet_supported = 1;
 389         if (server_supports("agent"))
 390                 agent_supported = 1;
 391         if (server_supports("no-thin"))
 392                 args->use_thin_pack = 0;
 393         if (server_supports("atomic"))
 394                 atomic_supported = 1;
 395
 396         if (args->push_cert != SEND_PACK_PUSH_CERT_NEVER) {
 397                 int len;
 398                 push_cert_nonce = server_feature_value("push-cert", &len);
 399                 if (push_cert_nonce) {
 400                         reject_invalid_nonce(push_cert_nonce, len);
 401                         push_cert_nonce = xmemdupz(push_cert_nonce, len);
 402                 } else if (args->push_cert == SEND_PACK_PUSH_CERT_ALWAYS) {
 403                         die(_("the receiving end does not support --signed push"));
 404                 } else if (args->push_cert == SEND_PACK_PUSH_CERT_IF_ASKED) {
 405                         warning(_("not sending a push certificate since the"
 406                                   " receiving end does not support --signed"
 407                                   " push"));
 408                 }
 409         }
 410
 411         if (!remote_refs) {
 412                 fprintf(stderr, "No refs in common and none specified; doing nothing.\n"
 413                         "Perhaps you should specify a branch such as 'master'.\n");
 414                 return 0;
 415         }
 416         if (args->atomic && !atomic_supported)
 417                 die(_("the receiving end does not support --atomic push"));
 418
 419         use_atomic = atomic_supported && args->atomic;
 420
 421         if (status_report)
 422                 strbuf_addstr(&cap_buf, " report-status");
 423         if (use_sideband)
 424                 strbuf_addstr(&cap_buf, " side-band-64k");
 425         if (quiet_supported && (args->quiet || !args->progress))
 426                 strbuf_addstr(&cap_buf, " quiet");
 427         if (use_atomic)
 428                 strbuf_addstr(&cap_buf, " atomic");
 429         if (agent_supported)
 430                 strbuf_addf(&cap_buf, " agent=%s", git_user_agent_sanitized());
 431
 432         /*
 433          * NEEDSWORK: why does delete-refs have to be so specific to
 434          * send-pack machinery that set_ref_status_for_push() cannot
 435          * set this bit for us???
 436          */
 437         for (ref = remote_refs; ref; ref = ref->next)
 438                 if (ref->deletion && !allow_deleting_refs)
 439                         ref->status = REF_STATUS_REJECT_NODELETE;
 440
 441         if (!args->dry_run)
 442                 advertise_shallow_grafts_buf(&req_buf);
 443
 444         if (!args->dry_run && push_cert_nonce)
 445                 cmds_sent = generate_push_cert(&req_buf, remote_refs, args,
 446                                                cap_buf.buf, push_cert_nonce);
 447
 448         /*
 449          * Clear the status for each ref and see if we need to send
 450          * the pack data.
 451          */
 452         for (ref = remote_refs; ref; ref = ref->next) {
 453                 switch (check_to_send_update(ref, args)) {
 454                 case 0: /* no error */
 455                         break;
 456                 case CHECK_REF_STATUS_REJECTED:
 457                         /*
 458                          * When we know the server would reject a ref update if
 459                          * we were to send it and we're trying to send the refs
 460                          * atomically, abort the whole operation.
 461                          */
 462                         if (use_atomic)
 463                                 return atomic_push_failure(args, remote_refs, ref);
 464                         /* Fallthrough for non atomic case. */
 465                 default:
 466                         continue;
 467                 }
 468                 if (!ref->deletion)
 469                         need_pack_data = 1;
 470
 471                 if (args->dry_run || !status_report)
 472                         ref->status = REF_STATUS_OK;
 473                 else
 474                         ref->status = REF_STATUS_EXPECTING_REPORT;
 475         }
 476
 477         /*
 478          * Finally, tell the other end!
 479          */
 480         for (ref = remote_refs; ref; ref = ref->next) {
 481                 char *old_hex, *new_hex;
 482
 483                 if (args->dry_run || push_cert_nonce)
 484                         continue;
 485
 486                 if (check_to_send_update(ref, args) < 0)
 487                         continue;
 488
 489                 old_hex = oid_to_hex(&ref->old_oid);
 490                 new_hex = oid_to_hex(&ref->new_oid);
 491                 if (!cmds_sent) {
 492                         packet_buf_write(&req_buf,
 493                                          "%s %s %s%c%s",
 494                                          old_hex, new_hex, ref->name, 0,
 495                                          cap_buf.buf);
 496                         cmds_sent = 1;
 497                 } else {
 498                         packet_buf_write(&req_buf, "%s %s %s",
 499                                          old_hex, new_hex, ref->name);
 500                 }
 501         }
 502
 503         if (args->stateless_rpc) {
 504                 if (!args->dry_run && (cmds_sent || is_repository_shallow())) {
 505                         packet_buf_flush(&req_buf);
 506                         send_sideband(out, -1, req_buf.buf, req_buf.len, LARGE_PACKET_MAX);
 507                 }
 508         } else {
 509                 write_or_die(out, req_buf.buf, req_buf.len);
 510                 packet_flush(out);
 511         }
 512         strbuf_release(&req_buf);
 513         strbuf_release(&cap_buf);
 514
 515         if (use_sideband && cmds_sent) {
 516                 memset(&demux, 0, sizeof(demux));
 517                 demux.proc = sideband_demux;
 518                 demux.data = fd;
 519                 demux.out = -1;
 520                 demux.isolate_sigpipe = 1;
 521                 if (start_async(&demux))
 522                         die("send-pack: unable to fork off sideband demultiplexer");
 523                 in = demux.out;
 524         }
 525
 526         if (need_pack_data && cmds_sent) {
 527                 if (pack_objects(out, remote_refs, extra_have, args) < 0) {
 528                         for (ref = remote_refs; ref; ref = ref->next)
 529                                 ref->status = REF_STATUS_NONE;
 530                         if (args->stateless_rpc)
 531                                 close(out);
 532                         if (git_connection_is_socket(conn))
 533                                 shutdown(fd[0], SHUT_WR);
 534                         if (use_sideband) {
 535                                 close(demux.out);
 536                                 finish_async(&demux);
 537                         }
 538                         fd[1] = -1;
 539                         return -1;
 540                 }
 541                 if (!args->stateless_rpc)
 542                         /* Closed by pack_objects() via start_command() */
 543                         fd[1] = -1;
 544         }
 545         if (args->stateless_rpc && cmds_sent)
 546                 packet_flush(out);
 547
 548         if (status_report && cmds_sent)
 549                 ret = receive_status(in, remote_refs);
 550         else
 551                 ret = 0;
 552         if (args->stateless_rpc)
 553                 packet_flush(out);
 554
 555         if (use_sideband && cmds_sent) {
 556                 close(demux.out);
 557                 if (finish_async(&demux)) {
 558                         error("error in sideband demultiplexer");
 559                         ret = -1;
 560                 }
 561         }
 562
 563         if (ret < 0)
 564                 return ret;
 565
 566         if (args->porcelain)
 567                 return 0;
 568
 569         for (ref = remote_refs; ref; ref = ref->next) {
 570                 switch (ref->status) {
 571                 case REF_STATUS_NONE:
 572                 case REF_STATUS_UPTODATE:
 573                 case REF_STATUS_OK:
 574                         break;
 575                 default:
 576                         return -1;
 577                 }
 578         }
 579         return 0;
 580 }