Andrew's git / gitweb.git / connect.c
?
connect.con commit http: use curl's tcp keepalive if available (47ce115)
   1#include "git-compat-util.h"
   2#include "cache.h"
   3#include "pkt-line.h"
   4#include "quote.h"
   5#include "refs.h"
   6#include "run-command.h"
   7#include "remote.h"
   8#include "url.h"
   9
  10static char *server_capabilities;
  11
  12static int check_ref(const char *name, int len, unsigned int flags)
  13{
  14        if (!flags)
  15                return 1;
  16
  17        if (len < 5 || memcmp(name, "refs/", 5))
  18                return 0;
  19
  20        /* Skip the "refs/" part */
  21        name += 5;
  22        len -= 5;
  23
  24        /* REF_NORMAL means that we don't want the magic fake tag refs */
  25        if ((flags & REF_NORMAL) && check_ref_format(name) < 0)
  26                return 0;
  27
  28        /* REF_HEADS means that we want regular branch heads */
  29        if ((flags & REF_HEADS) && !memcmp(name, "heads/", 6))
  30                return 1;
  31
  32        /* REF_TAGS means that we want tags */
  33        if ((flags & REF_TAGS) && !memcmp(name, "tags/", 5))
  34                return 1;
  35
  36        /* All type bits clear means that we are ok with anything */
  37        return !(flags & ~REF_NORMAL);
  38}
  39
  40int check_ref_type(const struct ref *ref, int flags)
  41{
  42        return check_ref(ref->name, strlen(ref->name), flags);
  43}
  44
  45static void add_extra_have(struct extra_have_objects *extra, unsigned char *sha1)
  46{
  47        ALLOC_GROW(extra->array, extra->nr + 1, extra->alloc);
  48        hashcpy(&(extra->array[extra->nr][0]), sha1);
  49        extra->nr++;
  50}
  51
  52/*
  53 * Read all the refs from the other end
  54 */
  55struct ref **get_remote_heads(int in, struct ref **list,
  56                              int nr_match, char **match,
  57                              unsigned int flags,
  58                              struct extra_have_objects *extra_have)
  59{
  60        *list = NULL;
  61        for (;;) {
  62                struct ref *ref;
  63                unsigned char old_sha1[20];
  64                static char buffer[1000];
  65                char *name;
  66                int len, name_len;
  67
  68                len = packet_read_line(in, buffer, sizeof(buffer));
  69                if (!len)
  70                        break;
  71                if (buffer[len-1] == '\n')
  72                        buffer[--len] = 0;
  73
  74                if (len > 4 && !prefixcmp(buffer, "ERR "))
  75                        die("remote error: %s", buffer + 4);
  76
  77                if (len < 42 || get_sha1_hex(buffer, old_sha1) || buffer[40] != ' ')
  78                        die("protocol error: expected sha/ref, got '%s'", buffer);
  79                name = buffer + 41;
  80
  81                name_len = strlen(name);
  82                if (len != name_len + 41) {
  83                        free(server_capabilities);
  84                        server_capabilities = xstrdup(name + name_len + 1);
  85                }
  86
  87                if (extra_have &&
  88                    name_len == 5 && !memcmp(".have", name, 5)) {
  89                        add_extra_have(extra_have, old_sha1);
  90                        continue;
  91                }
  92
  93                if (!check_ref(name, name_len, flags))
  94                        continue;
  95                if (nr_match && !path_match(name, nr_match, match))
  96                        continue;
  97                ref = alloc_ref(buffer + 41);
  98                hashcpy(ref->old_sha1, old_sha1);
  99                *list = ref;
 100                list = &ref->next;
 101        }
 102        return list;
 103}
 104
 105int server_supports(const char *feature)
 106{
 107        return server_capabilities &&
 108                strstr(server_capabilities, feature) != NULL;
 109}
 110
 111int path_match(const char *path, int nr, char **match)
 112{
 113        int i;
 114        int pathlen = strlen(path);
 115
 116        for (i = 0; i < nr; i++) {
 117                char *s = match[i];
 118                int len = strlen(s);
 119
 120                if (!len || len > pathlen)
 121                        continue;
 122                if (memcmp(path + pathlen - len, s, len))
 123                        continue;
 124                if (pathlen > len && path[pathlen - len - 1] != '/')
 125                        continue;
 126                *s = 0;
 127                return (i + 1);
 128        }
 129        return 0;
 130}
 131
 132enum protocol {
 133        PROTO_LOCAL = 1,
 134        PROTO_SSH,
 135        PROTO_GIT
 136};
 137
 138static enum protocol get_protocol(const char *name)
 139{
 140        if (!strcmp(name, "ssh"))
 141                return PROTO_SSH;
 142        if (!strcmp(name, "git"))
 143                return PROTO_GIT;
 144        if (!strcmp(name, "git+ssh"))
 145                return PROTO_SSH;
 146        if (!strcmp(name, "ssh+git"))
 147                return PROTO_SSH;
 148        if (!strcmp(name, "file"))
 149                return PROTO_LOCAL;
 150        die("I don't handle protocol '%s'", name);
 151}
 152
 153#define STR_(s) # s
 154#define STR(s)  STR_(s)
 155
 156static void get_host_and_port(char **host, const char **port)
 157{
 158        char *colon, *end;
 159
 160        if (*host[0] == '[') {
 161                end = strchr(*host + 1, ']');
 162                if (end) {
 163                        *end = 0;
 164                        end++;
 165                        (*host)++;
 166                } else
 167                        end = *host;
 168        } else
 169                end = *host;
 170        colon = strchr(end, ':');
 171
 172        if (colon) {
 173                *colon = 0;
 174                *port = colon + 1;
 175        }
 176}
 177
 178static void enable_keepalive(int sockfd)
 179{
 180        int ka = 1;
 181
 182        if (setsockopt(sockfd, SOL_SOCKET, SO_KEEPALIVE, &ka, sizeof(ka)) < 0)
 183                fprintf(stderr, "unable to set SO_KEEPALIVE on socket: %s\n",
 184                        strerror(errno));
 185}
 186
 187#ifndef NO_IPV6
 188
 189static const char *ai_name(const struct addrinfo *ai)
 190{
 191        static char addr[NI_MAXHOST];
 192        if (getnameinfo(ai->ai_addr, ai->ai_addrlen, addr, sizeof(addr), NULL, 0,
 193                        NI_NUMERICHOST) != 0)
 194                strcpy(addr, "(unknown)");
 195
 196        return addr;
 197}
 198
 199/*
 200 * Returns a connected socket() fd, or else die()s.
 201 */
 202static int git_tcp_connect_sock(char *host, int flags)
 203{
 204        struct strbuf error_message = STRBUF_INIT;
 205        int sockfd = -1;
 206        const char *port = STR(DEFAULT_GIT_PORT);
 207        struct addrinfo hints, *ai0, *ai;
 208        int gai;
 209        int cnt = 0;
 210
 211        get_host_and_port(&host, &port);
 212        if (!*port)
 213                port = "<none>";
 214
 215        memset(&hints, 0, sizeof(hints));
 216        hints.ai_socktype = SOCK_STREAM;
 217        hints.ai_protocol = IPPROTO_TCP;
 218
 219        if (flags & CONNECT_VERBOSE)
 220                fprintf(stderr, "Looking up %s ... ", host);
 221
 222        gai = getaddrinfo(host, port, &hints, &ai);
 223        if (gai)
 224                die("Unable to look up %s (port %s) (%s)", host, port, gai_strerror(gai));
 225
 226        if (flags & CONNECT_VERBOSE)
 227                fprintf(stderr, "done.\nConnecting to %s (port %s) ... ", host, port);
 228
 229        for (ai0 = ai; ai; ai = ai->ai_next, cnt++) {
 230                sockfd = socket(ai->ai_family,
 231                                ai->ai_socktype, ai->ai_protocol);
 232                if ((sockfd < 0) ||
 233                    (connect(sockfd, ai->ai_addr, ai->ai_addrlen) < 0)) {
 234                        strbuf_addf(&error_message, "%s[%d: %s]: errno=%s\n",
 235                                    host, cnt, ai_name(ai), strerror(errno));
 236                        if (0 <= sockfd)
 237                                close(sockfd);
 238                        sockfd = -1;
 239                        continue;
 240                }
 241                if (flags & CONNECT_VERBOSE)
 242                        fprintf(stderr, "%s ", ai_name(ai));
 243                break;
 244        }
 245
 246        freeaddrinfo(ai0);
 247
 248        if (sockfd < 0)
 249                die("unable to connect to %s:\n%s", host, error_message.buf);
 250
 251        enable_keepalive(sockfd);
 252
 253        if (flags & CONNECT_VERBOSE)
 254                fprintf(stderr, "done.\n");
 255
 256        strbuf_release(&error_message);
 257
 258        return sockfd;
 259}
 260
 261#else /* NO_IPV6 */
 262
 263/*
 264 * Returns a connected socket() fd, or else die()s.
 265 */
 266static int git_tcp_connect_sock(char *host, int flags)
 267{
 268        int sockfd = -1, saved_errno = 0;
 269        const char *port = STR(DEFAULT_GIT_PORT);
 270        char *ep;
 271        struct hostent *he;
 272        struct sockaddr_in sa;
 273        char **ap;
 274        unsigned int nport;
 275        int cnt;
 276
 277        get_host_and_port(&host, &port);
 278
 279        if (flags & CONNECT_VERBOSE)
 280                fprintf(stderr, "Looking up %s ... ", host);
 281
 282        he = gethostbyname(host);
 283        if (!he)
 284                die("Unable to look up %s (%s)", host, hstrerror(h_errno));
 285        nport = strtoul(port, &ep, 10);
 286        if ( ep == port || *ep ) {
 287                /* Not numeric */
 288                struct servent *se = getservbyname(port,"tcp");
 289                if ( !se )
 290                        die("Unknown port %s", port);
 291                nport = se->s_port;
 292        }
 293
 294        if (flags & CONNECT_VERBOSE)
 295                fprintf(stderr, "done.\nConnecting to %s (port %s) ... ", host, port);
 296
 297        for (cnt = 0, ap = he->h_addr_list; *ap; ap++, cnt++) {
 298                sockfd = socket(he->h_addrtype, SOCK_STREAM, 0);
 299                if (sockfd < 0) {
 300                        saved_errno = errno;
 301                        continue;
 302                }
 303
 304                memset(&sa, 0, sizeof sa);
 305                sa.sin_family = he->h_addrtype;
 306                sa.sin_port = htons(nport);
 307                memcpy(&sa.sin_addr, *ap, he->h_length);
 308
 309                if (connect(sockfd, (struct sockaddr *)&sa, sizeof sa) < 0) {
 310                        saved_errno = errno;
 311                        fprintf(stderr, "%s[%d: %s]: errno=%s\n",
 312                                host,
 313                                cnt,
 314                                inet_ntoa(*(struct in_addr *)&sa.sin_addr),
 315                                strerror(saved_errno));
 316                        close(sockfd);
 317                        sockfd = -1;
 318                        continue;
 319                }
 320                if (flags & CONNECT_VERBOSE)
 321                        fprintf(stderr, "%s ",
 322                                inet_ntoa(*(struct in_addr *)&sa.sin_addr));
 323                break;
 324        }
 325
 326        if (sockfd < 0)
 327                die("unable to connect a socket (%s)", strerror(saved_errno));
 328
 329        enable_keepalive(sockfd);
 330
 331        if (flags & CONNECT_VERBOSE)
 332                fprintf(stderr, "done.\n");
 333
 334        return sockfd;
 335}
 336
 337#endif /* NO_IPV6 */
 338
 339
 340static void git_tcp_connect(int fd[2], char *host, int flags)
 341{
 342        int sockfd = git_tcp_connect_sock(host, flags);
 343
 344        fd[0] = sockfd;
 345        fd[1] = dup(sockfd);
 346}
 347
 348
 349static char *git_proxy_command;
 350
 351static int git_proxy_command_options(const char *var, const char *value,
 352                void *cb)
 353{
 354        if (!strcmp(var, "core.gitproxy")) {
 355                const char *for_pos;
 356                int matchlen = -1;
 357                int hostlen;
 358                const char *rhost_name = cb;
 359                int rhost_len = strlen(rhost_name);
 360
 361                if (git_proxy_command)
 362                        return 0;
 363                if (!value)
 364                        return config_error_nonbool(var);
 365                /* [core]
 366                 * ;# matches www.kernel.org as well
 367                 * gitproxy = netcatter-1 for kernel.org
 368                 * gitproxy = netcatter-2 for sample.xz
 369                 * gitproxy = netcatter-default
 370                 */
 371                for_pos = strstr(value, " for ");
 372                if (!for_pos)
 373                        /* matches everybody */
 374                        matchlen = strlen(value);
 375                else {
 376                        hostlen = strlen(for_pos + 5);
 377                        if (rhost_len < hostlen)
 378                                matchlen = -1;
 379                        else if (!strncmp(for_pos + 5,
 380                                          rhost_name + rhost_len - hostlen,
 381                                          hostlen) &&
 382                                 ((rhost_len == hostlen) ||
 383                                  rhost_name[rhost_len - hostlen -1] == '.'))
 384                                matchlen = for_pos - value;
 385                        else
 386                                matchlen = -1;
 387                }
 388                if (0 <= matchlen) {
 389                        /* core.gitproxy = none for kernel.org */
 390                        if (matchlen == 4 &&
 391                            !memcmp(value, "none", 4))
 392                                matchlen = 0;
 393                        git_proxy_command = xmemdupz(value, matchlen);
 394                }
 395                return 0;
 396        }
 397
 398        return git_default_config(var, value, cb);
 399}
 400
 401static int git_use_proxy(const char *host)
 402{
 403        git_proxy_command = getenv("GIT_PROXY_COMMAND");
 404        git_config(git_proxy_command_options, (void*)host);
 405        return (git_proxy_command && *git_proxy_command);
 406}
 407
 408static struct child_process *git_proxy_connect(int fd[2], char *host)
 409{
 410        const char *port = STR(DEFAULT_GIT_PORT);
 411        const char **argv;
 412        struct child_process *proxy;
 413
 414        get_host_and_port(&host, &port);
 415
 416        argv = xmalloc(sizeof(*argv) * 4);
 417        argv[0] = git_proxy_command;
 418        argv[1] = host;
 419        argv[2] = port;
 420        argv[3] = NULL;
 421        proxy = xcalloc(1, sizeof(*proxy));
 422        proxy->argv = argv;
 423        proxy->in = -1;
 424        proxy->out = -1;
 425        if (start_command(proxy))
 426                die("cannot start proxy %s", argv[0]);
 427        fd[0] = proxy->out; /* read from proxy stdout */
 428        fd[1] = proxy->in;  /* write to proxy stdin */
 429        return proxy;
 430}
 431
 432#define MAX_CMD_LEN 1024
 433
 434static char *get_port(char *host)
 435{
 436        char *end;
 437        char *p = strchr(host, ':');
 438
 439        if (p) {
 440                long port = strtol(p + 1, &end, 10);
 441                if (end != p + 1 && *end == '\0' && 0 <= port && port < 65536) {
 442                        *p = '\0';
 443                        return p+1;
 444                }
 445        }
 446
 447        return NULL;
 448}
 449
 450static struct child_process no_fork;
 451
 452/*
 453 * This returns a dummy child_process if the transport protocol does not
 454 * need fork(2), or a struct child_process object if it does.  Once done,
 455 * finish the connection with finish_connect() with the value returned from
 456 * this function (it is safe to call finish_connect() with NULL to support
 457 * the former case).
 458 *
 459 * If it returns, the connect is successful; it just dies on errors (this
 460 * will hopefully be changed in a libification effort, to return NULL when
 461 * the connection failed).
 462 */
 463struct child_process *git_connect(int fd[2], const char *url_orig,
 464                                  const char *prog, int flags)
 465{
 466        char *url;
 467        char *host, *path;
 468        char *end;
 469        int c;
 470        struct child_process *conn = &no_fork;
 471        enum protocol protocol = PROTO_LOCAL;
 472        int free_path = 0;
 473        char *port = NULL;
 474        const char **arg;
 475        struct strbuf cmd;
 476
 477        /* Without this we cannot rely on waitpid() to tell
 478         * what happened to our children.
 479         */
 480        signal(SIGCHLD, SIG_DFL);
 481
 482        if (is_url(url_orig))
 483                url = url_decode(url_orig);
 484        else
 485                url = xstrdup(url_orig);
 486
 487        host = strstr(url, "://");
 488        if (host) {
 489                *host = '\0';
 490                protocol = get_protocol(url);
 491                host += 3;
 492                c = '/';
 493        } else {
 494                host = url;
 495                c = ':';
 496        }
 497
 498        /*
 499         * Don't do destructive transforms with git:// as that
 500         * protocol code does '[]' unwrapping of its own.
 501         */
 502        if (host[0] == '[') {
 503                end = strchr(host + 1, ']');
 504                if (end) {
 505                        if (protocol != PROTO_GIT) {
 506                                *end = 0;
 507                                host++;
 508                        }
 509                        end++;
 510                } else
 511                        end = host;
 512        } else
 513                end = host;
 514
 515        path = strchr(end, c);
 516        if (path && !has_dos_drive_prefix(end)) {
 517                if (c == ':') {
 518                        protocol = PROTO_SSH;
 519                        *path++ = '\0';
 520                }
 521        } else
 522                path = end;
 523
 524        if (!path || !*path)
 525                die("No path specified. See 'man git-pull' for valid url syntax");
 526
 527        /*
 528         * null-terminate hostname and point path to ~ for URL's like this:
 529         *    ssh://host.xz/~user/repo
 530         */
 531        if (protocol != PROTO_LOCAL && host != url) {
 532                char *ptr = path;
 533                if (path[1] == '~')
 534                        path++;
 535                else {
 536                        path = xstrdup(ptr);
 537                        free_path = 1;
 538                }
 539
 540                *ptr = '\0';
 541        }
 542
 543        /*
 544         * Add support for ssh port: ssh://host.xy:<port>/...
 545         */
 546        if (protocol == PROTO_SSH && host != url)
 547                port = get_port(host);
 548
 549        if (protocol == PROTO_GIT) {
 550                /* These underlying connection commands die() if they
 551                 * cannot connect.
 552                 */
 553                char *target_host = xstrdup(host);
 554                if (git_use_proxy(host))
 555                        conn = git_proxy_connect(fd, host);
 556                else
 557                        git_tcp_connect(fd, host, flags);
 558                /*
 559                 * Separate original protocol components prog and path
 560                 * from extended host header with a NUL byte.
 561                 *
 562                 * Note: Do not add any other headers here!  Doing so
 563                 * will cause older git-daemon servers to crash.
 564                 */
 565                packet_write(fd[1],
 566                             "%s %s%chost=%s%c",
 567                             prog, path, 0,
 568                             target_host, 0);
 569                free(target_host);
 570                free(url);
 571                if (free_path)
 572                        free(path);
 573                return conn;
 574        }
 575
 576        conn = xcalloc(1, sizeof(*conn));
 577
 578        strbuf_init(&cmd, MAX_CMD_LEN);
 579        strbuf_addstr(&cmd, prog);
 580        strbuf_addch(&cmd, ' ');
 581        sq_quote_buf(&cmd, path);
 582        if (cmd.len >= MAX_CMD_LEN)
 583                die("command line too long");
 584
 585        conn->in = conn->out = -1;
 586        conn->argv = arg = xcalloc(7, sizeof(*arg));
 587        if (protocol == PROTO_SSH) {
 588                const char *ssh = getenv("GIT_SSH");
 589                int putty = ssh && strcasestr(ssh, "plink");
 590                if (!ssh) ssh = "ssh";
 591
 592                *arg++ = ssh;
 593                if (putty && !strcasestr(ssh, "tortoiseplink"))
 594                        *arg++ = "-batch";
 595                if (port) {
 596                        /* P is for PuTTY, p is for OpenSSH */
 597                        *arg++ = putty ? "-P" : "-p";
 598                        *arg++ = port;
 599                }
 600                *arg++ = host;
 601        }
 602        else {
 603                /* remove repo-local variables from the environment */
 604                conn->env = local_repo_env;
 605                conn->use_shell = 1;
 606        }
 607        *arg++ = cmd.buf;
 608        *arg = NULL;
 609
 610        if (start_command(conn))
 611                die("unable to fork");
 612
 613        fd[0] = conn->out; /* read from child's stdout */
 614        fd[1] = conn->in;  /* write to child's stdin */
 615        strbuf_release(&cmd);
 616        free(url);
 617        if (free_path)
 618                free(path);
 619        return conn;
 620}
 621
 622int git_connection_is_socket(struct child_process *conn)
 623{
 624        return conn == &no_fork;
 625}
 626
 627int finish_connect(struct child_process *conn)
 628{
 629        int code;
 630        if (!conn || git_connection_is_socket(conn))
 631                return 0;
 632
 633        code = finish_command(conn);
 634        free(conn->argv);
 635        free(conn);
 636        return code;
 637}
 638
 639char *git_getpass(const char *prompt)
 640{
 641        const char *askpass;
 642        struct child_process pass;
 643        const char *args[3];
 644        static struct strbuf buffer = STRBUF_INIT;
 645
 646        askpass = getenv("GIT_ASKPASS");
 647        if (!askpass)
 648                askpass = askpass_program;
 649        if (!askpass)
 650                askpass = getenv("SSH_ASKPASS");
 651        if (!askpass || !(*askpass)) {
 652                char *result = getpass(prompt);
 653                if (!result)
 654                        die_errno("Could not read password");
 655                return result;
 656        }
 657
 658        args[0] = askpass;
 659        args[1] = prompt;
 660        args[2] = NULL;
 661
 662        memset(&pass, 0, sizeof(pass));
 663        pass.argv = args;
 664        pass.out = -1;
 665
 666        if (start_command(&pass))
 667                exit(1);
 668
 669        strbuf_reset(&buffer);
 670        if (strbuf_read(&buffer, pass.out, 20) < 0)
 671                die("failed to read password from %s\n", askpass);
 672
 673        close(pass.out);
 674
 675        if (finish_command(&pass))
 676                exit(1);
 677
 678        strbuf_setlen(&buffer, strcspn(buffer.buf, "\r\n"));
 679
 680        return buffer.buf;
 681}