Andrew's git / gitweb.git / connect.c
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connect.con commit Merge branch 'sh/am-keep-cr' (c505a85)
   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
   9static char *server_capabilities;
  10
  11static int check_ref(const char *name, int len, unsigned int flags)
  12{
  13        if (!flags)
  14                return 1;
  15
  16        if (len < 5 || memcmp(name, "refs/", 5))
  17                return 0;
  18
  19        /* Skip the "refs/" part */
  20        name += 5;
  21        len -= 5;
  22
  23        /* REF_NORMAL means that we don't want the magic fake tag refs */
  24        if ((flags & REF_NORMAL) && check_ref_format(name) < 0)
  25                return 0;
  26
  27        /* REF_HEADS means that we want regular branch heads */
  28        if ((flags & REF_HEADS) && !memcmp(name, "heads/", 6))
  29                return 1;
  30
  31        /* REF_TAGS means that we want tags */
  32        if ((flags & REF_TAGS) && !memcmp(name, "tags/", 5))
  33                return 1;
  34
  35        /* All type bits clear means that we are ok with anything */
  36        return !(flags & ~REF_NORMAL);
  37}
  38
  39int check_ref_type(const struct ref *ref, int flags)
  40{
  41        return check_ref(ref->name, strlen(ref->name), flags);
  42}
  43
  44static void add_extra_have(struct extra_have_objects *extra, unsigned char *sha1)
  45{
  46        ALLOC_GROW(extra->array, extra->nr + 1, extra->alloc);
  47        hashcpy(&(extra->array[extra->nr][0]), sha1);
  48        extra->nr++;
  49}
  50
  51/*
  52 * Read all the refs from the other end
  53 */
  54struct ref **get_remote_heads(int in, struct ref **list,
  55                              int nr_match, char **match,
  56                              unsigned int flags,
  57                              struct extra_have_objects *extra_have)
  58{
  59        *list = NULL;
  60        for (;;) {
  61                struct ref *ref;
  62                unsigned char old_sha1[20];
  63                static char buffer[1000];
  64                char *name;
  65                int len, name_len;
  66
  67                len = packet_read_line(in, buffer, sizeof(buffer));
  68                if (!len)
  69                        break;
  70                if (buffer[len-1] == '\n')
  71                        buffer[--len] = 0;
  72
  73                if (len > 4 && !prefixcmp(buffer, "ERR "))
  74                        die("remote error: %s", buffer + 4);
  75
  76                if (len < 42 || get_sha1_hex(buffer, old_sha1) || buffer[40] != ' ')
  77                        die("protocol error: expected sha/ref, got '%s'", buffer);
  78                name = buffer + 41;
  79
  80                name_len = strlen(name);
  81                if (len != name_len + 41) {
  82                        free(server_capabilities);
  83                        server_capabilities = xstrdup(name + name_len + 1);
  84                }
  85
  86                if (extra_have &&
  87                    name_len == 5 && !memcmp(".have", name, 5)) {
  88                        add_extra_have(extra_have, old_sha1);
  89                        continue;
  90                }
  91
  92                if (!check_ref(name, name_len, flags))
  93                        continue;
  94                if (nr_match && !path_match(name, nr_match, match))
  95                        continue;
  96                ref = alloc_ref(buffer + 41);
  97                hashcpy(ref->old_sha1, old_sha1);
  98                *list = ref;
  99                list = &ref->next;
 100        }
 101        return list;
 102}
 103
 104int server_supports(const char *feature)
 105{
 106        return server_capabilities &&
 107                strstr(server_capabilities, feature) != NULL;
 108}
 109
 110int path_match(const char *path, int nr, char **match)
 111{
 112        int i;
 113        int pathlen = strlen(path);
 114
 115        for (i = 0; i < nr; i++) {
 116                char *s = match[i];
 117                int len = strlen(s);
 118
 119                if (!len || len > pathlen)
 120                        continue;
 121                if (memcmp(path + pathlen - len, s, len))
 122                        continue;
 123                if (pathlen > len && path[pathlen - len - 1] != '/')
 124                        continue;
 125                *s = 0;
 126                return (i + 1);
 127        }
 128        return 0;
 129}
 130
 131enum protocol {
 132        PROTO_LOCAL = 1,
 133        PROTO_SSH,
 134        PROTO_GIT,
 135};
 136
 137static enum protocol get_protocol(const char *name)
 138{
 139        if (!strcmp(name, "ssh"))
 140                return PROTO_SSH;
 141        if (!strcmp(name, "git"))
 142                return PROTO_GIT;
 143        if (!strcmp(name, "git+ssh"))
 144                return PROTO_SSH;
 145        if (!strcmp(name, "ssh+git"))
 146                return PROTO_SSH;
 147        if (!strcmp(name, "file"))
 148                return PROTO_LOCAL;
 149        die("I don't handle protocol '%s'", name);
 150}
 151
 152#define STR_(s) # s
 153#define STR(s)  STR_(s)
 154
 155static void get_host_and_port(char **host, const char **port)
 156{
 157        char *colon, *end;
 158
 159        if (*host[0] == '[') {
 160                end = strchr(*host + 1, ']');
 161                if (end) {
 162                        *end = 0;
 163                        end++;
 164                        (*host)++;
 165                } else
 166                        end = *host;
 167        } else
 168                end = *host;
 169        colon = strchr(end, ':');
 170
 171        if (colon) {
 172                *colon = 0;
 173                *port = colon + 1;
 174        }
 175}
 176
 177#ifndef NO_IPV6
 178
 179static const char *ai_name(const struct addrinfo *ai)
 180{
 181        static char addr[NI_MAXHOST];
 182        if (getnameinfo(ai->ai_addr, ai->ai_addrlen, addr, sizeof(addr), NULL, 0,
 183                        NI_NUMERICHOST) != 0)
 184                strcpy(addr, "(unknown)");
 185
 186        return addr;
 187}
 188
 189/*
 190 * Returns a connected socket() fd, or else die()s.
 191 */
 192static int git_tcp_connect_sock(char *host, int flags)
 193{
 194        int sockfd = -1, saved_errno = 0;
 195        const char *port = STR(DEFAULT_GIT_PORT);
 196        struct addrinfo hints, *ai0, *ai;
 197        int gai;
 198        int cnt = 0;
 199
 200        get_host_and_port(&host, &port);
 201        if (!*port)
 202                port = "<none>";
 203
 204        memset(&hints, 0, sizeof(hints));
 205        hints.ai_socktype = SOCK_STREAM;
 206        hints.ai_protocol = IPPROTO_TCP;
 207
 208        if (flags & CONNECT_VERBOSE)
 209                fprintf(stderr, "Looking up %s ... ", host);
 210
 211        gai = getaddrinfo(host, port, &hints, &ai);
 212        if (gai)
 213                die("Unable to look up %s (port %s) (%s)", host, port, gai_strerror(gai));
 214
 215        if (flags & CONNECT_VERBOSE)
 216                fprintf(stderr, "done.\nConnecting to %s (port %s) ... ", host, port);
 217
 218        for (ai0 = ai; ai; ai = ai->ai_next) {
 219                sockfd = socket(ai->ai_family,
 220                                ai->ai_socktype, ai->ai_protocol);
 221                if (sockfd < 0) {
 222                        saved_errno = errno;
 223                        continue;
 224                }
 225                if (connect(sockfd, ai->ai_addr, ai->ai_addrlen) < 0) {
 226                        saved_errno = errno;
 227                        fprintf(stderr, "%s[%d: %s]: errno=%s\n",
 228                                host,
 229                                cnt,
 230                                ai_name(ai),
 231                                strerror(saved_errno));
 232                        close(sockfd);
 233                        sockfd = -1;
 234                        continue;
 235                }
 236                if (flags & CONNECT_VERBOSE)
 237                        fprintf(stderr, "%s ", ai_name(ai));
 238                break;
 239        }
 240
 241        freeaddrinfo(ai0);
 242
 243        if (sockfd < 0)
 244                die("unable to connect a socket (%s)", strerror(saved_errno));
 245
 246        if (flags & CONNECT_VERBOSE)
 247                fprintf(stderr, "done.\n");
 248
 249        return sockfd;
 250}
 251
 252#else /* NO_IPV6 */
 253
 254/*
 255 * Returns a connected socket() fd, or else die()s.
 256 */
 257static int git_tcp_connect_sock(char *host, int flags)
 258{
 259        int sockfd = -1, saved_errno = 0;
 260        const char *port = STR(DEFAULT_GIT_PORT);
 261        char *ep;
 262        struct hostent *he;
 263        struct sockaddr_in sa;
 264        char **ap;
 265        unsigned int nport;
 266        int cnt;
 267
 268        get_host_and_port(&host, &port);
 269
 270        if (flags & CONNECT_VERBOSE)
 271                fprintf(stderr, "Looking up %s ... ", host);
 272
 273        he = gethostbyname(host);
 274        if (!he)
 275                die("Unable to look up %s (%s)", host, hstrerror(h_errno));
 276        nport = strtoul(port, &ep, 10);
 277        if ( ep == port || *ep ) {
 278                /* Not numeric */
 279                struct servent *se = getservbyname(port,"tcp");
 280                if ( !se )
 281                        die("Unknown port %s", port);
 282                nport = se->s_port;
 283        }
 284
 285        if (flags & CONNECT_VERBOSE)
 286                fprintf(stderr, "done.\nConnecting to %s (port %s) ... ", host, port);
 287
 288        for (cnt = 0, ap = he->h_addr_list; *ap; ap++, cnt++) {
 289                sockfd = socket(he->h_addrtype, SOCK_STREAM, 0);
 290                if (sockfd < 0) {
 291                        saved_errno = errno;
 292                        continue;
 293                }
 294
 295                memset(&sa, 0, sizeof sa);
 296                sa.sin_family = he->h_addrtype;
 297                sa.sin_port = htons(nport);
 298                memcpy(&sa.sin_addr, *ap, he->h_length);
 299
 300                if (connect(sockfd, (struct sockaddr *)&sa, sizeof sa) < 0) {
 301                        saved_errno = errno;
 302                        fprintf(stderr, "%s[%d: %s]: errno=%s\n",
 303                                host,
 304                                cnt,
 305                                inet_ntoa(*(struct in_addr *)&sa.sin_addr),
 306                                strerror(saved_errno));
 307                        close(sockfd);
 308                        sockfd = -1;
 309                        continue;
 310                }
 311                if (flags & CONNECT_VERBOSE)
 312                        fprintf(stderr, "%s ",
 313                                inet_ntoa(*(struct in_addr *)&sa.sin_addr));
 314                break;
 315        }
 316
 317        if (sockfd < 0)
 318                die("unable to connect a socket (%s)", strerror(saved_errno));
 319
 320        if (flags & CONNECT_VERBOSE)
 321                fprintf(stderr, "done.\n");
 322
 323        return sockfd;
 324}
 325
 326#endif /* NO_IPV6 */
 327
 328
 329static void git_tcp_connect(int fd[2], char *host, int flags)
 330{
 331        int sockfd = git_tcp_connect_sock(host, flags);
 332
 333        fd[0] = sockfd;
 334        fd[1] = dup(sockfd);
 335}
 336
 337
 338static char *git_proxy_command;
 339
 340static int git_proxy_command_options(const char *var, const char *value,
 341                void *cb)
 342{
 343        if (!strcmp(var, "core.gitproxy")) {
 344                const char *for_pos;
 345                int matchlen = -1;
 346                int hostlen;
 347                const char *rhost_name = cb;
 348                int rhost_len = strlen(rhost_name);
 349
 350                if (git_proxy_command)
 351                        return 0;
 352                if (!value)
 353                        return config_error_nonbool(var);
 354                /* [core]
 355                 * ;# matches www.kernel.org as well
 356                 * gitproxy = netcatter-1 for kernel.org
 357                 * gitproxy = netcatter-2 for sample.xz
 358                 * gitproxy = netcatter-default
 359                 */
 360                for_pos = strstr(value, " for ");
 361                if (!for_pos)
 362                        /* matches everybody */
 363                        matchlen = strlen(value);
 364                else {
 365                        hostlen = strlen(for_pos + 5);
 366                        if (rhost_len < hostlen)
 367                                matchlen = -1;
 368                        else if (!strncmp(for_pos + 5,
 369                                          rhost_name + rhost_len - hostlen,
 370                                          hostlen) &&
 371                                 ((rhost_len == hostlen) ||
 372                                  rhost_name[rhost_len - hostlen -1] == '.'))
 373                                matchlen = for_pos - value;
 374                        else
 375                                matchlen = -1;
 376                }
 377                if (0 <= matchlen) {
 378                        /* core.gitproxy = none for kernel.org */
 379                        if (matchlen == 4 &&
 380                            !memcmp(value, "none", 4))
 381                                matchlen = 0;
 382                        git_proxy_command = xmemdupz(value, matchlen);
 383                }
 384                return 0;
 385        }
 386
 387        return git_default_config(var, value, cb);
 388}
 389
 390static int git_use_proxy(const char *host)
 391{
 392        git_proxy_command = getenv("GIT_PROXY_COMMAND");
 393        git_config(git_proxy_command_options, (void*)host);
 394        return (git_proxy_command && *git_proxy_command);
 395}
 396
 397static void git_proxy_connect(int fd[2], char *host)
 398{
 399        const char *port = STR(DEFAULT_GIT_PORT);
 400        const char *argv[4];
 401        struct child_process proxy;
 402
 403        get_host_and_port(&host, &port);
 404
 405        argv[0] = git_proxy_command;
 406        argv[1] = host;
 407        argv[2] = port;
 408        argv[3] = NULL;
 409        memset(&proxy, 0, sizeof(proxy));
 410        proxy.argv = argv;
 411        proxy.in = -1;
 412        proxy.out = -1;
 413        if (start_command(&proxy))
 414                die("cannot start proxy %s", argv[0]);
 415        fd[0] = proxy.out; /* read from proxy stdout */
 416        fd[1] = proxy.in;  /* write to proxy stdin */
 417}
 418
 419#define MAX_CMD_LEN 1024
 420
 421static char *get_port(char *host)
 422{
 423        char *end;
 424        char *p = strchr(host, ':');
 425
 426        if (p) {
 427                long port = strtol(p + 1, &end, 10);
 428                if (end != p + 1 && *end == '\0' && 0 <= port && port < 65536) {
 429                        *p = '\0';
 430                        return p+1;
 431                }
 432        }
 433
 434        return NULL;
 435}
 436
 437static struct child_process no_fork;
 438
 439/*
 440 * This returns a dummy child_process if the transport protocol does not
 441 * need fork(2), or a struct child_process object if it does.  Once done,
 442 * finish the connection with finish_connect() with the value returned from
 443 * this function (it is safe to call finish_connect() with NULL to support
 444 * the former case).
 445 *
 446 * If it returns, the connect is successful; it just dies on errors (this
 447 * will hopefully be changed in a libification effort, to return NULL when
 448 * the connection failed).
 449 */
 450struct child_process *git_connect(int fd[2], const char *url_orig,
 451                                  const char *prog, int flags)
 452{
 453        char *url = xstrdup(url_orig);
 454        char *host, *path;
 455        char *end;
 456        int c;
 457        struct child_process *conn;
 458        enum protocol protocol = PROTO_LOCAL;
 459        int free_path = 0;
 460        char *port = NULL;
 461        const char **arg;
 462        struct strbuf cmd;
 463
 464        /* Without this we cannot rely on waitpid() to tell
 465         * what happened to our children.
 466         */
 467        signal(SIGCHLD, SIG_DFL);
 468
 469        host = strstr(url, "://");
 470        if (host) {
 471                *host = '\0';
 472                protocol = get_protocol(url);
 473                host += 3;
 474                c = '/';
 475        } else {
 476                host = url;
 477                c = ':';
 478        }
 479
 480        /*
 481         * Don't do destructive transforms with git:// as that
 482         * protocol code does '[]' unwrapping of its own.
 483         */
 484        if (host[0] == '[') {
 485                end = strchr(host + 1, ']');
 486                if (end) {
 487                        if (protocol != PROTO_GIT) {
 488                                *end = 0;
 489                                host++;
 490                        }
 491                        end++;
 492                } else
 493                        end = host;
 494        } else
 495                end = host;
 496
 497        path = strchr(end, c);
 498        if (path && !has_dos_drive_prefix(end)) {
 499                if (c == ':') {
 500                        protocol = PROTO_SSH;
 501                        *path++ = '\0';
 502                }
 503        } else
 504                path = end;
 505
 506        if (!path || !*path)
 507                die("No path specified. See 'man git-pull' for valid url syntax");
 508
 509        /*
 510         * null-terminate hostname and point path to ~ for URL's like this:
 511         *    ssh://host.xz/~user/repo
 512         */
 513        if (protocol != PROTO_LOCAL && host != url) {
 514                char *ptr = path;
 515                if (path[1] == '~')
 516                        path++;
 517                else {
 518                        path = xstrdup(ptr);
 519                        free_path = 1;
 520                }
 521
 522                *ptr = '\0';
 523        }
 524
 525        /*
 526         * Add support for ssh port: ssh://host.xy:<port>/...
 527         */
 528        if (protocol == PROTO_SSH && host != url)
 529                port = get_port(host);
 530
 531        if (protocol == PROTO_GIT) {
 532                /* These underlying connection commands die() if they
 533                 * cannot connect.
 534                 */
 535                char *target_host = xstrdup(host);
 536                if (git_use_proxy(host))
 537                        git_proxy_connect(fd, host);
 538                else
 539                        git_tcp_connect(fd, host, flags);
 540                /*
 541                 * Separate original protocol components prog and path
 542                 * from extended host header with a NUL byte.
 543                 *
 544                 * Note: Do not add any other headers here!  Doing so
 545                 * will cause older git-daemon servers to crash.
 546                 */
 547                packet_write(fd[1],
 548                             "%s %s%chost=%s%c",
 549                             prog, path, 0,
 550                             target_host, 0);
 551                free(target_host);
 552                free(url);
 553                if (free_path)
 554                        free(path);
 555                return &no_fork;
 556        }
 557
 558        conn = xcalloc(1, sizeof(*conn));
 559
 560        strbuf_init(&cmd, MAX_CMD_LEN);
 561        strbuf_addstr(&cmd, prog);
 562        strbuf_addch(&cmd, ' ');
 563        sq_quote_buf(&cmd, path);
 564        if (cmd.len >= MAX_CMD_LEN)
 565                die("command line too long");
 566
 567        conn->in = conn->out = -1;
 568        conn->argv = arg = xcalloc(7, sizeof(*arg));
 569        if (protocol == PROTO_SSH) {
 570                const char *ssh = getenv("GIT_SSH");
 571                int putty = ssh && strcasestr(ssh, "plink");
 572                if (!ssh) ssh = "ssh";
 573
 574                *arg++ = ssh;
 575                if (putty && !strcasestr(ssh, "tortoiseplink"))
 576                        *arg++ = "-batch";
 577                if (port) {
 578                        /* P is for PuTTY, p is for OpenSSH */
 579                        *arg++ = putty ? "-P" : "-p";
 580                        *arg++ = port;
 581                }
 582                *arg++ = host;
 583        }
 584        else {
 585                /* remove repo-local variables from the environment */
 586                conn->env = local_repo_env;
 587                conn->use_shell = 1;
 588        }
 589        *arg++ = cmd.buf;
 590        *arg = NULL;
 591
 592        if (start_command(conn))
 593                die("unable to fork");
 594
 595        fd[0] = conn->out; /* read from child's stdout */
 596        fd[1] = conn->in;  /* write to child's stdin */
 597        strbuf_release(&cmd);
 598        free(url);
 599        if (free_path)
 600                free(path);
 601        return conn;
 602}
 603
 604int finish_connect(struct child_process *conn)
 605{
 606        int code;
 607        if (!conn || conn == &no_fork)
 608                return 0;
 609
 610        code = finish_command(conn);
 611        free(conn->argv);
 612        free(conn);
 613        return code;
 614}