Andrew's git / gitweb.git / connect.c
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connect.con commit git-p4: Cleanup; moved the code for the initial #head or revision import into a separate function, out of P4Sync.run. (c208a24)
   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
  39/*
  40 * Read all the refs from the other end
  41 */
  42struct ref **get_remote_heads(int in, struct ref **list,
  43                              int nr_match, char **match,
  44                              unsigned int flags)
  45{
  46        *list = NULL;
  47        for (;;) {
  48                struct ref *ref;
  49                unsigned char old_sha1[20];
  50                static char buffer[1000];
  51                char *name;
  52                int len, name_len;
  53
  54                len = packet_read_line(in, buffer, sizeof(buffer));
  55                if (!len)
  56                        break;
  57                if (buffer[len-1] == '\n')
  58                        buffer[--len] = 0;
  59
  60                if (len < 42 || get_sha1_hex(buffer, old_sha1) || buffer[40] != ' ')
  61                        die("protocol error: expected sha/ref, got '%s'", buffer);
  62                name = buffer + 41;
  63
  64                name_len = strlen(name);
  65                if (len != name_len + 41) {
  66                        if (server_capabilities)
  67                                free(server_capabilities);
  68                        server_capabilities = xstrdup(name + name_len + 1);
  69                }
  70
  71                if (!check_ref(name, name_len, flags))
  72                        continue;
  73                if (nr_match && !path_match(name, nr_match, match))
  74                        continue;
  75                ref = alloc_ref(len - 40);
  76                hashcpy(ref->old_sha1, old_sha1);
  77                memcpy(ref->name, buffer + 41, len - 40);
  78                *list = ref;
  79                list = &ref->next;
  80        }
  81        return list;
  82}
  83
  84int server_supports(const char *feature)
  85{
  86        return server_capabilities &&
  87                strstr(server_capabilities, feature) != NULL;
  88}
  89
  90int get_ack(int fd, unsigned char *result_sha1)
  91{
  92        static char line[1000];
  93        int len = packet_read_line(fd, line, sizeof(line));
  94
  95        if (!len)
  96                die("git-fetch-pack: expected ACK/NAK, got EOF");
  97        if (line[len-1] == '\n')
  98                line[--len] = 0;
  99        if (!strcmp(line, "NAK"))
 100                return 0;
 101        if (!prefixcmp(line, "ACK ")) {
 102                if (!get_sha1_hex(line+4, result_sha1)) {
 103                        if (strstr(line+45, "continue"))
 104                                return 2;
 105                        return 1;
 106                }
 107        }
 108        die("git-fetch_pack: expected ACK/NAK, got '%s'", line);
 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
 156#ifndef NO_IPV6
 157
 158static const char *ai_name(const struct addrinfo *ai)
 159{
 160        static char addr[INET_ADDRSTRLEN];
 161        if ( AF_INET == ai->ai_family ) {
 162                struct sockaddr_in *in;
 163                in = (struct sockaddr_in *)ai->ai_addr;
 164                inet_ntop(ai->ai_family, &in->sin_addr, addr, sizeof(addr));
 165        } else if ( AF_INET6 == ai->ai_family ) {
 166                struct sockaddr_in6 *in;
 167                in = (struct sockaddr_in6 *)ai->ai_addr;
 168                inet_ntop(ai->ai_family, &in->sin6_addr, addr, sizeof(addr));
 169        } else {
 170                strcpy(addr, "(unknown)");
 171        }
 172        return addr;
 173}
 174
 175/*
 176 * Returns a connected socket() fd, or else die()s.
 177 */
 178static int git_tcp_connect_sock(char *host, int flags)
 179{
 180        int sockfd = -1, saved_errno = 0;
 181        char *colon, *end;
 182        const char *port = STR(DEFAULT_GIT_PORT);
 183        struct addrinfo hints, *ai0, *ai;
 184        int gai;
 185        int cnt = 0;
 186
 187        if (host[0] == '[') {
 188                end = strchr(host + 1, ']');
 189                if (end) {
 190                        *end = 0;
 191                        end++;
 192                        host++;
 193                } else
 194                        end = host;
 195        } else
 196                end = host;
 197        colon = strchr(end, ':');
 198
 199        if (colon) {
 200                *colon = 0;
 201                port = colon + 1;
 202                if (!*port)
 203                        port = "<none>";
 204        }
 205
 206        memset(&hints, 0, sizeof(hints));
 207        hints.ai_socktype = SOCK_STREAM;
 208        hints.ai_protocol = IPPROTO_TCP;
 209
 210        if (flags & CONNECT_VERBOSE)
 211                fprintf(stderr, "Looking up %s ... ", host);
 212
 213        gai = getaddrinfo(host, port, &hints, &ai);
 214        if (gai)
 215                die("Unable to look up %s (port %s) (%s)", host, port, gai_strerror(gai));
 216
 217        if (flags & CONNECT_VERBOSE)
 218                fprintf(stderr, "done.\nConnecting to %s (port %s) ... ", host, port);
 219
 220        for (ai0 = ai; ai; ai = ai->ai_next) {
 221                sockfd = socket(ai->ai_family,
 222                                ai->ai_socktype, ai->ai_protocol);
 223                if (sockfd < 0) {
 224                        saved_errno = errno;
 225                        continue;
 226                }
 227                if (connect(sockfd, ai->ai_addr, ai->ai_addrlen) < 0) {
 228                        saved_errno = errno;
 229                        fprintf(stderr, "%s[%d: %s]: errno=%s\n",
 230                                host,
 231                                cnt,
 232                                ai_name(ai),
 233                                strerror(saved_errno));
 234                        close(sockfd);
 235                        sockfd = -1;
 236                        continue;
 237                }
 238                if (flags & CONNECT_VERBOSE)
 239                        fprintf(stderr, "%s ", ai_name(ai));
 240                break;
 241        }
 242
 243        freeaddrinfo(ai0);
 244
 245        if (sockfd < 0)
 246                die("unable to connect a socket (%s)", strerror(saved_errno));
 247
 248        if (flags & CONNECT_VERBOSE)
 249                fprintf(stderr, "done.\n");
 250
 251        return sockfd;
 252}
 253
 254#else /* NO_IPV6 */
 255
 256/*
 257 * Returns a connected socket() fd, or else die()s.
 258 */
 259static int git_tcp_connect_sock(char *host, int flags)
 260{
 261        int sockfd = -1, saved_errno = 0;
 262        char *colon, *end;
 263        char *port = STR(DEFAULT_GIT_PORT), *ep;
 264        struct hostent *he;
 265        struct sockaddr_in sa;
 266        char **ap;
 267        unsigned int nport;
 268        int cnt;
 269
 270        if (host[0] == '[') {
 271                end = strchr(host + 1, ']');
 272                if (end) {
 273                        *end = 0;
 274                        end++;
 275                        host++;
 276                } else
 277                        end = host;
 278        } else
 279                end = host;
 280        colon = strchr(end, ':');
 281
 282        if (colon) {
 283                *colon = 0;
 284                port = colon + 1;
 285        }
 286
 287        if (flags & CONNECT_VERBOSE)
 288                fprintf(stderr, "Looking up %s ... ", host);
 289
 290        he = gethostbyname(host);
 291        if (!he)
 292                die("Unable to look up %s (%s)", host, hstrerror(h_errno));
 293        nport = strtoul(port, &ep, 10);
 294        if ( ep == port || *ep ) {
 295                /* Not numeric */
 296                struct servent *se = getservbyname(port,"tcp");
 297                if ( !se )
 298                        die("Unknown port %s\n", port);
 299                nport = se->s_port;
 300        }
 301
 302        if (flags & CONNECT_VERBOSE)
 303                fprintf(stderr, "done.\nConnecting to %s (port %s) ... ", host, port);
 304
 305        for (cnt = 0, ap = he->h_addr_list; *ap; ap++, cnt++) {
 306                sockfd = socket(he->h_addrtype, SOCK_STREAM, 0);
 307                if (sockfd < 0) {
 308                        saved_errno = errno;
 309                        continue;
 310                }
 311
 312                memset(&sa, 0, sizeof sa);
 313                sa.sin_family = he->h_addrtype;
 314                sa.sin_port = htons(nport);
 315                memcpy(&sa.sin_addr, *ap, he->h_length);
 316
 317                if (connect(sockfd, (struct sockaddr *)&sa, sizeof sa) < 0) {
 318                        saved_errno = errno;
 319                        fprintf(stderr, "%s[%d: %s]: errno=%s\n",
 320                                host,
 321                                cnt,
 322                                inet_ntoa(*(struct in_addr *)&sa.sin_addr),
 323                                strerror(saved_errno));
 324                        close(sockfd);
 325                        sockfd = -1;
 326                        continue;
 327                }
 328                if (flags & CONNECT_VERBOSE)
 329                        fprintf(stderr, "%s ",
 330                                inet_ntoa(*(struct in_addr *)&sa.sin_addr));
 331                break;
 332        }
 333
 334        if (sockfd < 0)
 335                die("unable to connect a socket (%s)", strerror(saved_errno));
 336
 337        if (flags & CONNECT_VERBOSE)
 338                fprintf(stderr, "done.\n");
 339
 340        return sockfd;
 341}
 342
 343#endif /* NO_IPV6 */
 344
 345
 346static void git_tcp_connect(int fd[2], char *host, int flags)
 347{
 348        int sockfd = git_tcp_connect_sock(host, flags);
 349
 350        fd[0] = sockfd;
 351        fd[1] = dup(sockfd);
 352}
 353
 354
 355static char *git_proxy_command;
 356static const char *rhost_name;
 357static int rhost_len;
 358
 359static int git_proxy_command_options(const char *var, const char *value)
 360{
 361        if (!strcmp(var, "core.gitproxy")) {
 362                const char *for_pos;
 363                int matchlen = -1;
 364                int hostlen;
 365
 366                if (git_proxy_command)
 367                        return 0;
 368                /* [core]
 369                 * ;# matches www.kernel.org as well
 370                 * gitproxy = netcatter-1 for kernel.org
 371                 * gitproxy = netcatter-2 for sample.xz
 372                 * gitproxy = netcatter-default
 373                 */
 374                for_pos = strstr(value, " for ");
 375                if (!for_pos)
 376                        /* matches everybody */
 377                        matchlen = strlen(value);
 378                else {
 379                        hostlen = strlen(for_pos + 5);
 380                        if (rhost_len < hostlen)
 381                                matchlen = -1;
 382                        else if (!strncmp(for_pos + 5,
 383                                          rhost_name + rhost_len - hostlen,
 384                                          hostlen) &&
 385                                 ((rhost_len == hostlen) ||
 386                                  rhost_name[rhost_len - hostlen -1] == '.'))
 387                                matchlen = for_pos - value;
 388                        else
 389                                matchlen = -1;
 390                }
 391                if (0 <= matchlen) {
 392                        /* core.gitproxy = none for kernel.org */
 393                        if (matchlen == 4 &&
 394                            !memcmp(value, "none", 4))
 395                                matchlen = 0;
 396                        git_proxy_command = xmalloc(matchlen + 1);
 397                        memcpy(git_proxy_command, value, matchlen);
 398                        git_proxy_command[matchlen] = 0;
 399                }
 400                return 0;
 401        }
 402
 403        return git_default_config(var, value);
 404}
 405
 406static int git_use_proxy(const char *host)
 407{
 408        rhost_name = host;
 409        rhost_len = strlen(host);
 410        git_proxy_command = getenv("GIT_PROXY_COMMAND");
 411        git_config(git_proxy_command_options);
 412        rhost_name = NULL;
 413        return (git_proxy_command && *git_proxy_command);
 414}
 415
 416static void git_proxy_connect(int fd[2], char *host)
 417{
 418        const char *port = STR(DEFAULT_GIT_PORT);
 419        char *colon, *end;
 420        const char *argv[4];
 421        struct child_process proxy;
 422
 423        if (host[0] == '[') {
 424                end = strchr(host + 1, ']');
 425                if (end) {
 426                        *end = 0;
 427                        end++;
 428                        host++;
 429                } else
 430                        end = host;
 431        } else
 432                end = host;
 433        colon = strchr(end, ':');
 434
 435        if (colon) {
 436                *colon = 0;
 437                port = colon + 1;
 438        }
 439
 440        argv[0] = git_proxy_command;
 441        argv[1] = host;
 442        argv[2] = port;
 443        argv[3] = NULL;
 444        memset(&proxy, 0, sizeof(proxy));
 445        proxy.argv = argv;
 446        proxy.in = -1;
 447        proxy.out = -1;
 448        if (start_command(&proxy))
 449                die("cannot start proxy %s", argv[0]);
 450        fd[0] = proxy.out; /* read from proxy stdout */
 451        fd[1] = proxy.in;  /* write to proxy stdin */
 452}
 453
 454#define MAX_CMD_LEN 1024
 455
 456char *get_port(char *host)
 457{
 458        char *end;
 459        char *p = strchr(host, ':');
 460
 461        if (p) {
 462                strtol(p+1, &end, 10);
 463                if (*end == '\0') {
 464                        *p = '\0';
 465                        return p+1;
 466                }
 467        }
 468
 469        return NULL;
 470}
 471
 472/*
 473 * This returns 0 if the transport protocol does not need fork(2),
 474 * or a process id if it does.  Once done, finish the connection
 475 * with finish_connect() with the value returned from this function
 476 * (it is safe to call finish_connect() with 0 to support the former
 477 * case).
 478 *
 479 * Does not return a negative value on error; it just dies.
 480 */
 481pid_t git_connect(int fd[2], char *url, const char *prog, int flags)
 482{
 483        char *host, *path = url;
 484        char *end;
 485        int c;
 486        int pipefd[2][2];
 487        pid_t pid;
 488        enum protocol protocol = PROTO_LOCAL;
 489        int free_path = 0;
 490        char *port = NULL;
 491
 492        /* Without this we cannot rely on waitpid() to tell
 493         * what happened to our children.
 494         */
 495        signal(SIGCHLD, SIG_DFL);
 496
 497        host = strstr(url, "://");
 498        if(host) {
 499                *host = '\0';
 500                protocol = get_protocol(url);
 501                host += 3;
 502                c = '/';
 503        } else {
 504                host = url;
 505                c = ':';
 506        }
 507
 508        if (host[0] == '[') {
 509                end = strchr(host + 1, ']');
 510                if (end) {
 511                        *end = 0;
 512                        end++;
 513                        host++;
 514                } else
 515                        end = host;
 516        } else
 517                end = host;
 518
 519        path = strchr(end, c);
 520        if (path) {
 521                if (c == ':') {
 522                        protocol = PROTO_SSH;
 523                        *path++ = '\0';
 524                }
 525        } else
 526                path = end;
 527
 528        if (!path || !*path)
 529                die("No path specified. See 'man git-pull' for valid url syntax");
 530
 531        /*
 532         * null-terminate hostname and point path to ~ for URL's like this:
 533         *    ssh://host.xz/~user/repo
 534         */
 535        if (protocol != PROTO_LOCAL && host != url) {
 536                char *ptr = path;
 537                if (path[1] == '~')
 538                        path++;
 539                else {
 540                        path = xstrdup(ptr);
 541                        free_path = 1;
 542                }
 543
 544                *ptr = '\0';
 545        }
 546
 547        /*
 548         * Add support for ssh port: ssh://host.xy:<port>/...
 549         */
 550        if (protocol == PROTO_SSH && host != url)
 551                port = get_port(host);
 552
 553        if (protocol == PROTO_GIT) {
 554                /* These underlying connection commands die() if they
 555                 * cannot connect.
 556                 */
 557                char *target_host = xstrdup(host);
 558                if (git_use_proxy(host))
 559                        git_proxy_connect(fd, host);
 560                else
 561                        git_tcp_connect(fd, host, flags);
 562                /*
 563                 * Separate original protocol components prog and path
 564                 * from extended components with a NUL byte.
 565                 */
 566                packet_write(fd[1],
 567                             "%s %s%chost=%s%c",
 568                             prog, path, 0,
 569                             target_host, 0);
 570                free(target_host);
 571                if (free_path)
 572                        free(path);
 573                return 0;
 574        }
 575
 576        if (pipe(pipefd[0]) < 0 || pipe(pipefd[1]) < 0)
 577                die("unable to create pipe pair for communication");
 578        pid = fork();
 579        if (pid < 0)
 580                die("unable to fork");
 581        if (!pid) {
 582                char command[MAX_CMD_LEN];
 583                char *posn = command;
 584                int size = MAX_CMD_LEN;
 585                int of = 0;
 586
 587                of |= add_to_string(&posn, &size, prog, 0);
 588                of |= add_to_string(&posn, &size, " ", 0);
 589                of |= add_to_string(&posn, &size, path, 1);
 590
 591                if (of)
 592                        die("command line too long");
 593
 594                dup2(pipefd[1][0], 0);
 595                dup2(pipefd[0][1], 1);
 596                close(pipefd[0][0]);
 597                close(pipefd[0][1]);
 598                close(pipefd[1][0]);
 599                close(pipefd[1][1]);
 600                if (protocol == PROTO_SSH) {
 601                        const char *ssh, *ssh_basename;
 602                        ssh = getenv("GIT_SSH");
 603                        if (!ssh) ssh = "ssh";
 604                        ssh_basename = strrchr(ssh, '/');
 605                        if (!ssh_basename)
 606                                ssh_basename = ssh;
 607                        else
 608                                ssh_basename++;
 609
 610                        if (!port)
 611                                execlp(ssh, ssh_basename, host, command, NULL);
 612                        else
 613                                execlp(ssh, ssh_basename, "-p", port, host,
 614                                       command, NULL);
 615                }
 616                else {
 617                        unsetenv(ALTERNATE_DB_ENVIRONMENT);
 618                        unsetenv(DB_ENVIRONMENT);
 619                        unsetenv(GIT_DIR_ENVIRONMENT);
 620                        unsetenv(GIT_WORK_TREE_ENVIRONMENT);
 621                        unsetenv(GRAFT_ENVIRONMENT);
 622                        unsetenv(INDEX_ENVIRONMENT);
 623                        execlp("sh", "sh", "-c", command, NULL);
 624                }
 625                die("exec failed");
 626        }
 627        fd[0] = pipefd[0][0];
 628        fd[1] = pipefd[1][1];
 629        close(pipefd[0][1]);
 630        close(pipefd[1][0]);
 631        if (free_path)
 632                free(path);
 633        return pid;
 634}
 635
 636int finish_connect(pid_t pid)
 637{
 638        if (pid == 0)
 639                return 0;
 640
 641        while (waitpid(pid, NULL, 0) < 0) {
 642                if (errno != EINTR)
 643                        return -1;
 644        }
 645        return 0;
 646}