send-pack.con commit diff-tree: update stale in-code comments (8ba74bf)
   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
  16static int feed_object(const unsigned char *sha1, int fd, int negative)
  17{
  18        char buf[42];
  19
  20        if (negative && !has_sha1_file(sha1))
  21                return 1;
  22
  23        memcpy(buf + negative, sha1_to_hex(sha1), 40);
  24        if (negative)
  25                buf[0] = '^';
  26        buf[40 + negative] = '\n';
  27        return write_or_whine(fd, buf, 41 + negative, "send-pack: send refs");
  28}
  29
  30/*
  31 * Make a pack stream and spit it out into file descriptor fd
  32 */
  33static int pack_objects(int fd, struct ref *refs, struct sha1_array *extra, struct send_pack_args *args)
  34{
  35        /*
  36         * The child becomes pack-objects --revs; we feed
  37         * the revision parameters to it via its stdin and
  38         * let its stdout go back to the other end.
  39         */
  40        const char *argv[] = {
  41                "pack-objects",
  42                "--all-progress-implied",
  43                "--revs",
  44                "--stdout",
  45                NULL,
  46                NULL,
  47                NULL,
  48                NULL,
  49                NULL,
  50                NULL,
  51        };
  52        struct child_process po = CHILD_PROCESS_INIT;
  53        int i;
  54
  55        i = 4;
  56        if (args->use_thin_pack)
  57                argv[i++] = "--thin";
  58        if (args->use_ofs_delta)
  59                argv[i++] = "--delta-base-offset";
  60        if (args->quiet || !args->progress)
  61                argv[i++] = "-q";
  62        if (args->progress)
  63                argv[i++] = "--progress";
  64        if (is_repository_shallow())
  65                argv[i++] = "--shallow";
  66        po.argv = argv;
  67        po.in = -1;
  68        po.out = args->stateless_rpc ? -1 : fd;
  69        po.git_cmd = 1;
  70        if (start_command(&po))
  71                die_errno("git pack-objects failed");
  72
  73        /*
  74         * We feed the pack-objects we just spawned with revision
  75         * parameters by writing to the pipe.
  76         */
  77        for (i = 0; i < extra->nr; i++)
  78                if (!feed_object(extra->sha1[i], po.in, 1))
  79                        break;
  80
  81        while (refs) {
  82                if (!is_null_sha1(refs->old_sha1) &&
  83                    !feed_object(refs->old_sha1, po.in, 1))
  84                        break;
  85                if (!is_null_sha1(refs->new_sha1) &&
  86                    !feed_object(refs->new_sha1, po.in, 0))
  87                        break;
  88                refs = refs->next;
  89        }
  90
  91        close(po.in);
  92
  93        if (args->stateless_rpc) {
  94                char *buf = xmalloc(LARGE_PACKET_MAX);
  95                while (1) {
  96                        ssize_t n = xread(po.out, buf, LARGE_PACKET_MAX);
  97                        if (n <= 0)
  98                                break;
  99                        send_sideband(fd, -1, buf, n, LARGE_PACKET_MAX);
 100                }
 101                free(buf);
 102                close(po.out);
 103                po.out = -1;
 104        }
 105
 106        if (finish_command(&po))
 107                return -1;
 108        return 0;
 109}
 110
 111static int receive_status(int in, struct ref *refs)
 112{
 113        struct ref *hint;
 114        int ret = 0;
 115        char *line = packet_read_line(in, NULL);
 116        if (!starts_with(line, "unpack "))
 117                return error("did not receive remote status");
 118        if (strcmp(line, "unpack ok")) {
 119                error("unpack failed: %s", line + 7);
 120                ret = -1;
 121        }
 122        hint = NULL;
 123        while (1) {
 124                char *refname;
 125                char *msg;
 126                line = packet_read_line(in, NULL);
 127                if (!line)
 128                        break;
 129                if (!starts_with(line, "ok ") && !starts_with(line, "ng ")) {
 130                        error("invalid ref status from remote: %s", line);
 131                        ret = -1;
 132                        break;
 133                }
 134
 135                refname = line + 3;
 136                msg = strchr(refname, ' ');
 137                if (msg)
 138                        *msg++ = '\0';
 139
 140                /* first try searching at our hint, falling back to all refs */
 141                if (hint)
 142                        hint = find_ref_by_name(hint, refname);
 143                if (!hint)
 144                        hint = find_ref_by_name(refs, refname);
 145                if (!hint) {
 146                        warning("remote reported status on unknown ref: %s",
 147                                        refname);
 148                        continue;
 149                }
 150                if (hint->status != REF_STATUS_EXPECTING_REPORT) {
 151                        warning("remote reported status on unexpected ref: %s",
 152                                        refname);
 153                        continue;
 154                }
 155
 156                if (line[0] == 'o' && line[1] == 'k')
 157                        hint->status = REF_STATUS_OK;
 158                else {
 159                        hint->status = REF_STATUS_REMOTE_REJECT;
 160                        ret = -1;
 161                }
 162                if (msg)
 163                        hint->remote_status = xstrdup(msg);
 164                /* start our next search from the next ref */
 165                hint = hint->next;
 166        }
 167        return ret;
 168}
 169
 170static int sideband_demux(int in, int out, void *data)
 171{
 172        int *fd = data, ret;
 173#ifdef NO_PTHREADS
 174        close(fd[1]);
 175#endif
 176        ret = recv_sideband("send-pack", fd[0], out);
 177        close(out);
 178        return ret;
 179}
 180
 181static int advertise_shallow_grafts_cb(const struct commit_graft *graft, void *cb)
 182{
 183        struct strbuf *sb = cb;
 184        if (graft->nr_parent == -1)
 185                packet_buf_write(sb, "shallow %s\n", sha1_to_hex(graft->sha1));
 186        return 0;
 187}
 188
 189static void advertise_shallow_grafts_buf(struct strbuf *sb)
 190{
 191        if (!is_repository_shallow())
 192                return;
 193        for_each_commit_graft(advertise_shallow_grafts_cb, sb);
 194}
 195
 196#define CHECK_REF_NO_PUSH -1
 197#define CHECK_REF_STATUS_REJECTED -2
 198#define CHECK_REF_UPTODATE -3
 199static int check_to_send_update(const struct ref *ref, const struct send_pack_args *args)
 200{
 201        if (!ref->peer_ref && !args->send_mirror)
 202                return CHECK_REF_NO_PUSH;
 203
 204        /* Check for statuses set by set_ref_status_for_push() */
 205        switch (ref->status) {
 206        case REF_STATUS_REJECT_NONFASTFORWARD:
 207        case REF_STATUS_REJECT_ALREADY_EXISTS:
 208        case REF_STATUS_REJECT_FETCH_FIRST:
 209        case REF_STATUS_REJECT_NEEDS_FORCE:
 210        case REF_STATUS_REJECT_STALE:
 211        case REF_STATUS_REJECT_NODELETE:
 212                return CHECK_REF_STATUS_REJECTED;
 213        case REF_STATUS_UPTODATE:
 214                return CHECK_REF_UPTODATE;
 215        default:
 216                return 0;
 217        }
 218}
 219
 220/*
 221 * the beginning of the next line, or the end of buffer.
 222 *
 223 * NEEDSWORK: perhaps move this to git-compat-util.h or somewhere and
 224 * convert many similar uses found by "git grep -A4 memchr".
 225 */
 226static const char *next_line(const char *line, size_t len)
 227{
 228        const char *nl = memchr(line, '\n', len);
 229        if (!nl)
 230                return line + len; /* incomplete line */
 231        return nl + 1;
 232}
 233
 234static int generate_push_cert(struct strbuf *req_buf,
 235                              const struct ref *remote_refs,
 236                              struct send_pack_args *args,
 237                              const char *cap_string,
 238                              const char *push_cert_nonce)
 239{
 240        const struct ref *ref;
 241        char *signing_key = xstrdup(get_signing_key());
 242        const char *cp, *np;
 243        struct strbuf cert = STRBUF_INIT;
 244        int update_seen = 0;
 245
 246        strbuf_addf(&cert, "certificate version 0.1\n");
 247        strbuf_addf(&cert, "pusher %s ", signing_key);
 248        datestamp(&cert);
 249        strbuf_addch(&cert, '\n');
 250        if (args->url && *args->url) {
 251                char *anon_url = transport_anonymize_url(args->url);
 252                strbuf_addf(&cert, "pushee %s\n", anon_url);
 253                free(anon_url);
 254        }
 255        if (push_cert_nonce[0])
 256                strbuf_addf(&cert, "nonce %s\n", push_cert_nonce);
 257        strbuf_addstr(&cert, "\n");
 258
 259        for (ref = remote_refs; ref; ref = ref->next) {
 260                if (check_to_send_update(ref, args) < 0)
 261                        continue;
 262                update_seen = 1;
 263                strbuf_addf(&cert, "%s %s %s\n",
 264                            sha1_to_hex(ref->old_sha1),
 265                            sha1_to_hex(ref->new_sha1),
 266                            ref->name);
 267        }
 268        if (!update_seen)
 269                goto free_return;
 270
 271        if (sign_buffer(&cert, &cert, signing_key))
 272                die(_("failed to sign the push certificate"));
 273
 274        packet_buf_write(req_buf, "push-cert%c%s", 0, cap_string);
 275        for (cp = cert.buf; cp < cert.buf + cert.len; cp = np) {
 276                np = next_line(cp, cert.buf + cert.len - cp);
 277                packet_buf_write(req_buf,
 278                                 "%.*s", (int)(np - cp), cp);
 279        }
 280        packet_buf_write(req_buf, "push-cert-end\n");
 281
 282free_return:
 283        free(signing_key);
 284        strbuf_release(&cert);
 285        return update_seen;
 286}
 287
 288
 289static int atomic_push_failure(struct send_pack_args *args,
 290                               struct ref *remote_refs,
 291                               struct ref *failing_ref)
 292{
 293        struct ref *ref;
 294        /* Mark other refs as failed */
 295        for (ref = remote_refs; ref; ref = ref->next) {
 296                if (!ref->peer_ref && !args->send_mirror)
 297                        continue;
 298
 299                switch (ref->status) {
 300                case REF_STATUS_EXPECTING_REPORT:
 301                        ref->status = REF_STATUS_ATOMIC_PUSH_FAILED;
 302                        continue;
 303                default:
 304                        break; /* do nothing */
 305                }
 306        }
 307        return error("atomic push failed for ref %s. status: %d\n",
 308                     failing_ref->name, failing_ref->status);
 309}
 310
 311#define NONCE_LEN_LIMIT 256
 312
 313static void reject_invalid_nonce(const char *nonce, int len)
 314{
 315        int i = 0;
 316
 317        if (NONCE_LEN_LIMIT <= len)
 318                die("the receiving end asked to sign an invalid nonce <%.*s>",
 319                    len, nonce);
 320
 321        for (i = 0; i < len; i++) {
 322                int ch = nonce[i] & 0xFF;
 323                if (isalnum(ch) ||
 324                    ch == '-' || ch == '.' ||
 325                    ch == '/' || ch == '+' ||
 326                    ch == '=' || ch == '_')
 327                        continue;
 328                die("the receiving end asked to sign an invalid nonce <%.*s>",
 329                    len, nonce);
 330        }
 331}
 332
 333int send_pack(struct send_pack_args *args,
 334              int fd[], struct child_process *conn,
 335              struct ref *remote_refs,
 336              struct sha1_array *extra_have)
 337{
 338        int in = fd[0];
 339        int out = fd[1];
 340        struct strbuf req_buf = STRBUF_INIT;
 341        struct strbuf cap_buf = STRBUF_INIT;
 342        struct ref *ref;
 343        int need_pack_data = 0;
 344        int allow_deleting_refs = 0;
 345        int status_report = 0;
 346        int use_sideband = 0;
 347        int quiet_supported = 0;
 348        int agent_supported = 0;
 349        int use_atomic = 0;
 350        int atomic_supported = 0;
 351        unsigned cmds_sent = 0;
 352        int ret;
 353        struct async demux;
 354        const char *push_cert_nonce = NULL;
 355
 356        /* Does the other end support the reporting? */
 357        if (server_supports("report-status"))
 358                status_report = 1;
 359        if (server_supports("delete-refs"))
 360                allow_deleting_refs = 1;
 361        if (server_supports("ofs-delta"))
 362                args->use_ofs_delta = 1;
 363        if (server_supports("side-band-64k"))
 364                use_sideband = 1;
 365        if (server_supports("quiet"))
 366                quiet_supported = 1;
 367        if (server_supports("agent"))
 368                agent_supported = 1;
 369        if (server_supports("no-thin"))
 370                args->use_thin_pack = 0;
 371        if (server_supports("atomic"))
 372                atomic_supported = 1;
 373        if (args->push_cert) {
 374                int len;
 375
 376                push_cert_nonce = server_feature_value("push-cert", &len);
 377                if (!push_cert_nonce)
 378                        die(_("the receiving end does not support --signed push"));
 379                reject_invalid_nonce(push_cert_nonce, len);
 380                push_cert_nonce = xmemdupz(push_cert_nonce, len);
 381        }
 382
 383        if (!remote_refs) {
 384                fprintf(stderr, "No refs in common and none specified; doing nothing.\n"
 385                        "Perhaps you should specify a branch such as 'master'.\n");
 386                return 0;
 387        }
 388        if (args->atomic && !atomic_supported)
 389                die(_("the receiving end does not support --atomic push"));
 390
 391        use_atomic = atomic_supported && args->atomic;
 392
 393        if (status_report)
 394                strbuf_addstr(&cap_buf, " report-status");
 395        if (use_sideband)
 396                strbuf_addstr(&cap_buf, " side-band-64k");
 397        if (quiet_supported && (args->quiet || !args->progress))
 398                strbuf_addstr(&cap_buf, " quiet");
 399        if (use_atomic)
 400                strbuf_addstr(&cap_buf, " atomic");
 401        if (agent_supported)
 402                strbuf_addf(&cap_buf, " agent=%s", git_user_agent_sanitized());
 403
 404        /*
 405         * NEEDSWORK: why does delete-refs have to be so specific to
 406         * send-pack machinery that set_ref_status_for_push() cannot
 407         * set this bit for us???
 408         */
 409        for (ref = remote_refs; ref; ref = ref->next)
 410                if (ref->deletion && !allow_deleting_refs)
 411                        ref->status = REF_STATUS_REJECT_NODELETE;
 412
 413        if (!args->dry_run)
 414                advertise_shallow_grafts_buf(&req_buf);
 415
 416        if (!args->dry_run && args->push_cert)
 417                cmds_sent = generate_push_cert(&req_buf, remote_refs, args,
 418                                               cap_buf.buf, push_cert_nonce);
 419
 420        /*
 421         * Clear the status for each ref and see if we need to send
 422         * the pack data.
 423         */
 424        for (ref = remote_refs; ref; ref = ref->next) {
 425                switch (check_to_send_update(ref, args)) {
 426                case 0: /* no error */
 427                        break;
 428                case CHECK_REF_STATUS_REJECTED:
 429                        /*
 430                         * When we know the server would reject a ref update if
 431                         * we were to send it and we're trying to send the refs
 432                         * atomically, abort the whole operation.
 433                         */
 434                        if (use_atomic)
 435                                return atomic_push_failure(args, remote_refs, ref);
 436                        /* Fallthrough for non atomic case. */
 437                default:
 438                        continue;
 439                }
 440                if (!ref->deletion)
 441                        need_pack_data = 1;
 442
 443                if (args->dry_run || !status_report)
 444                        ref->status = REF_STATUS_OK;
 445                else
 446                        ref->status = REF_STATUS_EXPECTING_REPORT;
 447        }
 448
 449        /*
 450         * Finally, tell the other end!
 451         */
 452        for (ref = remote_refs; ref; ref = ref->next) {
 453                char *old_hex, *new_hex;
 454
 455                if (args->dry_run || args->push_cert)
 456                        continue;
 457
 458                if (check_to_send_update(ref, args) < 0)
 459                        continue;
 460
 461                old_hex = sha1_to_hex(ref->old_sha1);
 462                new_hex = sha1_to_hex(ref->new_sha1);
 463                if (!cmds_sent) {
 464                        packet_buf_write(&req_buf,
 465                                         "%s %s %s%c%s",
 466                                         old_hex, new_hex, ref->name, 0,
 467                                         cap_buf.buf);
 468                        cmds_sent = 1;
 469                } else {
 470                        packet_buf_write(&req_buf, "%s %s %s",
 471                                         old_hex, new_hex, ref->name);
 472                }
 473        }
 474
 475        if (args->stateless_rpc) {
 476                if (!args->dry_run && (cmds_sent || is_repository_shallow())) {
 477                        packet_buf_flush(&req_buf);
 478                        send_sideband(out, -1, req_buf.buf, req_buf.len, LARGE_PACKET_MAX);
 479                }
 480        } else {
 481                write_or_die(out, req_buf.buf, req_buf.len);
 482                packet_flush(out);
 483        }
 484        strbuf_release(&req_buf);
 485        strbuf_release(&cap_buf);
 486
 487        if (use_sideband && cmds_sent) {
 488                memset(&demux, 0, sizeof(demux));
 489                demux.proc = sideband_demux;
 490                demux.data = fd;
 491                demux.out = -1;
 492                if (start_async(&demux))
 493                        die("send-pack: unable to fork off sideband demultiplexer");
 494                in = demux.out;
 495        }
 496
 497        if (need_pack_data && cmds_sent) {
 498                if (pack_objects(out, remote_refs, extra_have, args) < 0) {
 499                        for (ref = remote_refs; ref; ref = ref->next)
 500                                ref->status = REF_STATUS_NONE;
 501                        if (args->stateless_rpc)
 502                                close(out);
 503                        if (git_connection_is_socket(conn))
 504                                shutdown(fd[0], SHUT_WR);
 505                        if (use_sideband)
 506                                finish_async(&demux);
 507                        fd[1] = -1;
 508                        return -1;
 509                }
 510                if (!args->stateless_rpc)
 511                        /* Closed by pack_objects() via start_command() */
 512                        fd[1] = -1;
 513        }
 514        if (args->stateless_rpc && cmds_sent)
 515                packet_flush(out);
 516
 517        if (status_report && cmds_sent)
 518                ret = receive_status(in, remote_refs);
 519        else
 520                ret = 0;
 521        if (args->stateless_rpc)
 522                packet_flush(out);
 523
 524        if (use_sideband && cmds_sent) {
 525                if (finish_async(&demux)) {
 526                        error("error in sideband demultiplexer");
 527                        ret = -1;
 528                }
 529                close(demux.out);
 530        }
 531
 532        if (ret < 0)
 533                return ret;
 534
 535        if (args->porcelain)
 536                return 0;
 537
 538        for (ref = remote_refs; ref; ref = ref->next) {
 539                switch (ref->status) {
 540                case REF_STATUS_NONE:
 541                case REF_STATUS_UPTODATE:
 542                case REF_STATUS_OK:
 543                        break;
 544                default:
 545                        return -1;
 546                }
 547        }
 548        return 0;
 549}