Andrew's git / gitweb.git / connect.c
?
connect.con commit daemon: Strictly parse the "extra arg" part of the command (73bb33a)
   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 get_ack(int fd, unsigned char *result_sha1)
 111{
 112        static char line[1000];
 113        int len = packet_read_line(fd, line, sizeof(line));
 114
 115        if (!len)
 116                die("git fetch-pack: expected ACK/NAK, got EOF");
 117        if (line[len-1] == '\n')
 118                line[--len] = 0;
 119        if (!strcmp(line, "NAK"))
 120                return 0;
 121        if (!prefixcmp(line, "ACK ")) {
 122                if (!get_sha1_hex(line+4, result_sha1)) {
 123                        if (strstr(line+45, "continue"))
 124                                return 2;
 125                        return 1;
 126                }
 127        }
 128        die("git fetch_pack: expected ACK/NAK, got '%s'", line);
 129}
 130
 131int path_match(const char *path, int nr, char **match)
 132{
 133        int i;
 134        int pathlen = strlen(path);
 135
 136        for (i = 0; i < nr; i++) {
 137                char *s = match[i];
 138                int len = strlen(s);
 139
 140                if (!len || len > pathlen)
 141                        continue;
 142                if (memcmp(path + pathlen - len, s, len))
 143                        continue;
 144                if (pathlen > len && path[pathlen - len - 1] != '/')
 145                        continue;
 146                *s = 0;
 147                return (i + 1);
 148        }
 149        return 0;
 150}
 151
 152enum protocol {
 153        PROTO_LOCAL = 1,
 154        PROTO_SSH,
 155        PROTO_GIT,
 156};
 157
 158static enum protocol get_protocol(const char *name)
 159{
 160        if (!strcmp(name, "ssh"))
 161                return PROTO_SSH;
 162        if (!strcmp(name, "git"))
 163                return PROTO_GIT;
 164        if (!strcmp(name, "git+ssh"))
 165                return PROTO_SSH;
 166        if (!strcmp(name, "ssh+git"))
 167                return PROTO_SSH;
 168        if (!strcmp(name, "file"))
 169                return PROTO_LOCAL;
 170        die("I don't handle protocol '%s'", name);
 171}
 172
 173#define STR_(s) # s
 174#define STR(s)  STR_(s)
 175
 176#ifndef NO_IPV6
 177
 178static const char *ai_name(const struct addrinfo *ai)
 179{
 180        static char addr[NI_MAXHOST];
 181        if (getnameinfo(ai->ai_addr, ai->ai_addrlen, addr, sizeof(addr), NULL, 0,
 182                        NI_NUMERICHOST) != 0)
 183                strcpy(addr, "(unknown)");
 184
 185        return addr;
 186}
 187
 188/*
 189 * Returns a connected socket() fd, or else die()s.
 190 */
 191static int git_tcp_connect_sock(char *host, int flags)
 192{
 193        int sockfd = -1, saved_errno = 0;
 194        char *colon, *end;
 195        const char *port = STR(DEFAULT_GIT_PORT);
 196        struct addrinfo hints, *ai0, *ai;
 197        int gai;
 198        int cnt = 0;
 199
 200        if (host[0] == '[') {
 201                end = strchr(host + 1, ']');
 202                if (end) {
 203                        *end = 0;
 204                        end++;
 205                        host++;
 206                } else
 207                        end = host;
 208        } else
 209                end = host;
 210        colon = strchr(end, ':');
 211
 212        if (colon) {
 213                *colon = 0;
 214                port = colon + 1;
 215                if (!*port)
 216                        port = "<none>";
 217        }
 218
 219        memset(&hints, 0, sizeof(hints));
 220        hints.ai_socktype = SOCK_STREAM;
 221        hints.ai_protocol = IPPROTO_TCP;
 222
 223        if (flags & CONNECT_VERBOSE)
 224                fprintf(stderr, "Looking up %s ... ", host);
 225
 226        gai = getaddrinfo(host, port, &hints, &ai);
 227        if (gai)
 228                die("Unable to look up %s (port %s) (%s)", host, port, gai_strerror(gai));
 229
 230        if (flags & CONNECT_VERBOSE)
 231                fprintf(stderr, "done.\nConnecting to %s (port %s) ... ", host, port);
 232
 233        for (ai0 = ai; ai; ai = ai->ai_next) {
 234                sockfd = socket(ai->ai_family,
 235                                ai->ai_socktype, ai->ai_protocol);
 236                if (sockfd < 0) {
 237                        saved_errno = errno;
 238                        continue;
 239                }
 240                if (connect(sockfd, ai->ai_addr, ai->ai_addrlen) < 0) {
 241                        saved_errno = errno;
 242                        fprintf(stderr, "%s[%d: %s]: errno=%s\n",
 243                                host,
 244                                cnt,
 245                                ai_name(ai),
 246                                strerror(saved_errno));
 247                        close(sockfd);
 248                        sockfd = -1;
 249                        continue;
 250                }
 251                if (flags & CONNECT_VERBOSE)
 252                        fprintf(stderr, "%s ", ai_name(ai));
 253                break;
 254        }
 255
 256        freeaddrinfo(ai0);
 257
 258        if (sockfd < 0)
 259                die("unable to connect a socket (%s)", strerror(saved_errno));
 260
 261        if (flags & CONNECT_VERBOSE)
 262                fprintf(stderr, "done.\n");
 263
 264        return sockfd;
 265}
 266
 267#else /* NO_IPV6 */
 268
 269/*
 270 * Returns a connected socket() fd, or else die()s.
 271 */
 272static int git_tcp_connect_sock(char *host, int flags)
 273{
 274        int sockfd = -1, saved_errno = 0;
 275        char *colon, *end;
 276        char *port = STR(DEFAULT_GIT_PORT), *ep;
 277        struct hostent *he;
 278        struct sockaddr_in sa;
 279        char **ap;
 280        unsigned int nport;
 281        int cnt;
 282
 283        if (host[0] == '[') {
 284                end = strchr(host + 1, ']');
 285                if (end) {
 286                        *end = 0;
 287                        end++;
 288                        host++;
 289                } else
 290                        end = host;
 291        } else
 292                end = host;
 293        colon = strchr(end, ':');
 294
 295        if (colon) {
 296                *colon = 0;
 297                port = colon + 1;
 298        }
 299
 300        if (flags & CONNECT_VERBOSE)
 301                fprintf(stderr, "Looking up %s ... ", host);
 302
 303        he = gethostbyname(host);
 304        if (!he)
 305                die("Unable to look up %s (%s)", host, hstrerror(h_errno));
 306        nport = strtoul(port, &ep, 10);
 307        if ( ep == port || *ep ) {
 308                /* Not numeric */
 309                struct servent *se = getservbyname(port,"tcp");
 310                if ( !se )
 311                        die("Unknown port %s", port);
 312                nport = se->s_port;
 313        }
 314
 315        if (flags & CONNECT_VERBOSE)
 316                fprintf(stderr, "done.\nConnecting to %s (port %s) ... ", host, port);
 317
 318        for (cnt = 0, ap = he->h_addr_list; *ap; ap++, cnt++) {
 319                sockfd = socket(he->h_addrtype, SOCK_STREAM, 0);
 320                if (sockfd < 0) {
 321                        saved_errno = errno;
 322                        continue;
 323                }
 324
 325                memset(&sa, 0, sizeof sa);
 326                sa.sin_family = he->h_addrtype;
 327                sa.sin_port = htons(nport);
 328                memcpy(&sa.sin_addr, *ap, he->h_length);
 329
 330                if (connect(sockfd, (struct sockaddr *)&sa, sizeof sa) < 0) {
 331                        saved_errno = errno;
 332                        fprintf(stderr, "%s[%d: %s]: errno=%s\n",
 333                                host,
 334                                cnt,
 335                                inet_ntoa(*(struct in_addr *)&sa.sin_addr),
 336                                strerror(saved_errno));
 337                        close(sockfd);
 338                        sockfd = -1;
 339                        continue;
 340                }
 341                if (flags & CONNECT_VERBOSE)
 342                        fprintf(stderr, "%s ",
 343                                inet_ntoa(*(struct in_addr *)&sa.sin_addr));
 344                break;
 345        }
 346
 347        if (sockfd < 0)
 348                die("unable to connect a socket (%s)", strerror(saved_errno));
 349
 350        if (flags & CONNECT_VERBOSE)
 351                fprintf(stderr, "done.\n");
 352
 353        return sockfd;
 354}
 355
 356#endif /* NO_IPV6 */
 357
 358
 359static void git_tcp_connect(int fd[2], char *host, int flags)
 360{
 361        int sockfd = git_tcp_connect_sock(host, flags);
 362
 363        fd[0] = sockfd;
 364        fd[1] = dup(sockfd);
 365}
 366
 367
 368static char *git_proxy_command;
 369
 370static int git_proxy_command_options(const char *var, const char *value,
 371                void *cb)
 372{
 373        if (!strcmp(var, "core.gitproxy")) {
 374                const char *for_pos;
 375                int matchlen = -1;
 376                int hostlen;
 377                const char *rhost_name = cb;
 378                int rhost_len = strlen(rhost_name);
 379
 380                if (git_proxy_command)
 381                        return 0;
 382                if (!value)
 383                        return config_error_nonbool(var);
 384                /* [core]
 385                 * ;# matches www.kernel.org as well
 386                 * gitproxy = netcatter-1 for kernel.org
 387                 * gitproxy = netcatter-2 for sample.xz
 388                 * gitproxy = netcatter-default
 389                 */
 390                for_pos = strstr(value, " for ");
 391                if (!for_pos)
 392                        /* matches everybody */
 393                        matchlen = strlen(value);
 394                else {
 395                        hostlen = strlen(for_pos + 5);
 396                        if (rhost_len < hostlen)
 397                                matchlen = -1;
 398                        else if (!strncmp(for_pos + 5,
 399                                          rhost_name + rhost_len - hostlen,
 400                                          hostlen) &&
 401                                 ((rhost_len == hostlen) ||
 402                                  rhost_name[rhost_len - hostlen -1] == '.'))
 403                                matchlen = for_pos - value;
 404                        else
 405                                matchlen = -1;
 406                }
 407                if (0 <= matchlen) {
 408                        /* core.gitproxy = none for kernel.org */
 409                        if (matchlen == 4 &&
 410                            !memcmp(value, "none", 4))
 411                                matchlen = 0;
 412                        git_proxy_command = xmemdupz(value, matchlen);
 413                }
 414                return 0;
 415        }
 416
 417        return git_default_config(var, value, cb);
 418}
 419
 420static int git_use_proxy(const char *host)
 421{
 422        git_proxy_command = getenv("GIT_PROXY_COMMAND");
 423        git_config(git_proxy_command_options, (void*)host);
 424        return (git_proxy_command && *git_proxy_command);
 425}
 426
 427static void git_proxy_connect(int fd[2], char *host)
 428{
 429        const char *port = STR(DEFAULT_GIT_PORT);
 430        char *colon, *end;
 431        const char *argv[4];
 432        struct child_process proxy;
 433
 434        if (host[0] == '[') {
 435                end = strchr(host + 1, ']');
 436                if (end) {
 437                        *end = 0;
 438                        end++;
 439                        host++;
 440                } else
 441                        end = host;
 442        } else
 443                end = host;
 444        colon = strchr(end, ':');
 445
 446        if (colon) {
 447                *colon = 0;
 448                port = colon + 1;
 449        }
 450
 451        argv[0] = git_proxy_command;
 452        argv[1] = host;
 453        argv[2] = port;
 454        argv[3] = NULL;
 455        memset(&proxy, 0, sizeof(proxy));
 456        proxy.argv = argv;
 457        proxy.in = -1;
 458        proxy.out = -1;
 459        if (start_command(&proxy))
 460                die("cannot start proxy %s", argv[0]);
 461        fd[0] = proxy.out; /* read from proxy stdout */
 462        fd[1] = proxy.in;  /* write to proxy stdin */
 463}
 464
 465#define MAX_CMD_LEN 1024
 466
 467char *get_port(char *host)
 468{
 469        char *end;
 470        char *p = strchr(host, ':');
 471
 472        if (p) {
 473                long port = strtol(p + 1, &end, 10);
 474                if (end != p + 1 && *end == '\0' && 0 <= port && port < 65536) {
 475                        *p = '\0';
 476                        return p+1;
 477                }
 478        }
 479
 480        return NULL;
 481}
 482
 483static struct child_process no_fork;
 484
 485/*
 486 * This returns a dummy child_process if the transport protocol does not
 487 * need fork(2), or a struct child_process object if it does.  Once done,
 488 * finish the connection with finish_connect() with the value returned from
 489 * this function (it is safe to call finish_connect() with NULL to support
 490 * the former case).
 491 *
 492 * If it returns, the connect is successful; it just dies on errors (this
 493 * will hopefully be changed in a libification effort, to return NULL when
 494 * the connection failed).
 495 */
 496struct child_process *git_connect(int fd[2], const char *url_orig,
 497                                  const char *prog, int flags)
 498{
 499        char *url = xstrdup(url_orig);
 500        char *host, *path;
 501        char *end;
 502        int c;
 503        struct child_process *conn;
 504        enum protocol protocol = PROTO_LOCAL;
 505        int free_path = 0;
 506        char *port = NULL;
 507        const char **arg;
 508        struct strbuf cmd;
 509
 510        /* Without this we cannot rely on waitpid() to tell
 511         * what happened to our children.
 512         */
 513        signal(SIGCHLD, SIG_DFL);
 514
 515        host = strstr(url, "://");
 516        if(host) {
 517                *host = '\0';
 518                protocol = get_protocol(url);
 519                host += 3;
 520                c = '/';
 521        } else {
 522                host = url;
 523                c = ':';
 524        }
 525
 526        if (host[0] == '[') {
 527                end = strchr(host + 1, ']');
 528                if (end) {
 529                        *end = 0;
 530                        end++;
 531                        host++;
 532                } else
 533                        end = host;
 534        } else
 535                end = host;
 536
 537        path = strchr(end, c);
 538        if (path && !has_dos_drive_prefix(end)) {
 539                if (c == ':') {
 540                        protocol = PROTO_SSH;
 541                        *path++ = '\0';
 542                }
 543        } else
 544                path = end;
 545
 546        if (!path || !*path)
 547                die("No path specified. See 'man git-pull' for valid url syntax");
 548
 549        /*
 550         * null-terminate hostname and point path to ~ for URL's like this:
 551         *    ssh://host.xz/~user/repo
 552         */
 553        if (protocol != PROTO_LOCAL && host != url) {
 554                char *ptr = path;
 555                if (path[1] == '~')
 556                        path++;
 557                else {
 558                        path = xstrdup(ptr);
 559                        free_path = 1;
 560                }
 561
 562                *ptr = '\0';
 563        }
 564
 565        /*
 566         * Add support for ssh port: ssh://host.xy:<port>/...
 567         */
 568        if (protocol == PROTO_SSH && host != url)
 569                port = get_port(host);
 570
 571        if (protocol == PROTO_GIT) {
 572                /* These underlying connection commands die() if they
 573                 * cannot connect.
 574                 */
 575                char *target_host = xstrdup(host);
 576                if (git_use_proxy(host))
 577                        git_proxy_connect(fd, host);
 578                else
 579                        git_tcp_connect(fd, host, flags);
 580                /*
 581                 * Separate original protocol components prog and path
 582                 * from extended host header with a NUL byte.
 583                 *
 584                 * Note: Do not add any other headers here!  Doing so
 585                 * will cause older git-daemon servers to crash.
 586                 */
 587                packet_write(fd[1],
 588                             "%s %s%chost=%s%c",
 589                             prog, path, 0,
 590                             target_host, 0);
 591                free(target_host);
 592                free(url);
 593                if (free_path)
 594                        free(path);
 595                return &no_fork;
 596        }
 597
 598        conn = xcalloc(1, sizeof(*conn));
 599
 600        strbuf_init(&cmd, MAX_CMD_LEN);
 601        strbuf_addstr(&cmd, prog);
 602        strbuf_addch(&cmd, ' ');
 603        sq_quote_buf(&cmd, path);
 604        if (cmd.len >= MAX_CMD_LEN)
 605                die("command line too long");
 606
 607        conn->in = conn->out = -1;
 608        conn->argv = arg = xcalloc(6, sizeof(*arg));
 609        if (protocol == PROTO_SSH) {
 610                const char *ssh = getenv("GIT_SSH");
 611                if (!ssh) ssh = "ssh";
 612
 613                *arg++ = ssh;
 614                if (port) {
 615                        *arg++ = "-p";
 616                        *arg++ = port;
 617                }
 618                *arg++ = host;
 619        }
 620        else {
 621                /* remove these from the environment */
 622                const char *env[] = {
 623                        ALTERNATE_DB_ENVIRONMENT,
 624                        DB_ENVIRONMENT,
 625                        GIT_DIR_ENVIRONMENT,
 626                        GIT_WORK_TREE_ENVIRONMENT,
 627                        GRAFT_ENVIRONMENT,
 628                        INDEX_ENVIRONMENT,
 629                        NULL
 630                };
 631                conn->env = env;
 632                *arg++ = "sh";
 633                *arg++ = "-c";
 634        }
 635        *arg++ = cmd.buf;
 636        *arg = NULL;
 637
 638        if (start_command(conn))
 639                die("unable to fork");
 640
 641        fd[0] = conn->out; /* read from child's stdout */
 642        fd[1] = conn->in;  /* write to child's stdin */
 643        strbuf_release(&cmd);
 644        free(url);
 645        if (free_path)
 646                free(path);
 647        return conn;
 648}
 649
 650int finish_connect(struct child_process *conn)
 651{
 652        int code;
 653        if (!conn || conn == &no_fork)
 654                return 0;
 655
 656        code = finish_command(conn);
 657        free(conn->argv);
 658        free(conn);
 659        return code;
 660}