Andrew's git / gitweb.git / connect.c
?
connect.con commit Merge branch 'jk/maint-push-over-dav' (1d3a035)
   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_refname_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                              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                ref = alloc_ref(buffer + 41);
  95                hashcpy(ref->old_sha1, old_sha1);
  96                *list = ref;
  97                list = &ref->next;
  98        }
  99        return list;
 100}
 101
 102int server_supports(const char *feature)
 103{
 104        return server_capabilities &&
 105                strstr(server_capabilities, feature) != NULL;
 106}
 107
 108enum protocol {
 109        PROTO_LOCAL = 1,
 110        PROTO_SSH,
 111        PROTO_GIT
 112};
 113
 114static enum protocol get_protocol(const char *name)
 115{
 116        if (!strcmp(name, "ssh"))
 117                return PROTO_SSH;
 118        if (!strcmp(name, "git"))
 119                return PROTO_GIT;
 120        if (!strcmp(name, "git+ssh"))
 121                return PROTO_SSH;
 122        if (!strcmp(name, "ssh+git"))
 123                return PROTO_SSH;
 124        if (!strcmp(name, "file"))
 125                return PROTO_LOCAL;
 126        die("I don't handle protocol '%s'", name);
 127}
 128
 129#define STR_(s) # s
 130#define STR(s)  STR_(s)
 131
 132static void get_host_and_port(char **host, const char **port)
 133{
 134        char *colon, *end;
 135
 136        if (*host[0] == '[') {
 137                end = strchr(*host + 1, ']');
 138                if (end) {
 139                        *end = 0;
 140                        end++;
 141                        (*host)++;
 142                } else
 143                        end = *host;
 144        } else
 145                end = *host;
 146        colon = strchr(end, ':');
 147
 148        if (colon) {
 149                *colon = 0;
 150                *port = colon + 1;
 151        }
 152}
 153
 154#ifndef NO_IPV6
 155
 156static const char *ai_name(const struct addrinfo *ai)
 157{
 158        static char addr[NI_MAXHOST];
 159        if (getnameinfo(ai->ai_addr, ai->ai_addrlen, addr, sizeof(addr), NULL, 0,
 160                        NI_NUMERICHOST) != 0)
 161                strcpy(addr, "(unknown)");
 162
 163        return addr;
 164}
 165
 166/*
 167 * Returns a connected socket() fd, or else die()s.
 168 */
 169static int git_tcp_connect_sock(char *host, int flags)
 170{
 171        struct strbuf error_message = STRBUF_INIT;
 172        int sockfd = -1;
 173        const char *port = STR(DEFAULT_GIT_PORT);
 174        struct addrinfo hints, *ai0, *ai;
 175        int gai;
 176        int cnt = 0;
 177
 178        get_host_and_port(&host, &port);
 179        if (!*port)
 180                port = "<none>";
 181
 182        memset(&hints, 0, sizeof(hints));
 183        hints.ai_socktype = SOCK_STREAM;
 184        hints.ai_protocol = IPPROTO_TCP;
 185
 186        if (flags & CONNECT_VERBOSE)
 187                fprintf(stderr, "Looking up %s ... ", host);
 188
 189        gai = getaddrinfo(host, port, &hints, &ai);
 190        if (gai)
 191                die("Unable to look up %s (port %s) (%s)", host, port, gai_strerror(gai));
 192
 193        if (flags & CONNECT_VERBOSE)
 194                fprintf(stderr, "done.\nConnecting to %s (port %s) ... ", host, port);
 195
 196        for (ai0 = ai; ai; ai = ai->ai_next, cnt++) {
 197                sockfd = socket(ai->ai_family,
 198                                ai->ai_socktype, ai->ai_protocol);
 199                if ((sockfd < 0) ||
 200                    (connect(sockfd, ai->ai_addr, ai->ai_addrlen) < 0)) {
 201                        strbuf_addf(&error_message, "%s[%d: %s]: errno=%s\n",
 202                                    host, cnt, ai_name(ai), strerror(errno));
 203                        if (0 <= sockfd)
 204                                close(sockfd);
 205                        sockfd = -1;
 206                        continue;
 207                }
 208                if (flags & CONNECT_VERBOSE)
 209                        fprintf(stderr, "%s ", ai_name(ai));
 210                break;
 211        }
 212
 213        freeaddrinfo(ai0);
 214
 215        if (sockfd < 0)
 216                die("unable to connect to %s:\n%s", host, error_message.buf);
 217
 218        if (flags & CONNECT_VERBOSE)
 219                fprintf(stderr, "done.\n");
 220
 221        strbuf_release(&error_message);
 222
 223        return sockfd;
 224}
 225
 226#else /* NO_IPV6 */
 227
 228/*
 229 * Returns a connected socket() fd, or else die()s.
 230 */
 231static int git_tcp_connect_sock(char *host, int flags)
 232{
 233        struct strbuf error_message = STRBUF_INIT;
 234        int sockfd = -1;
 235        const char *port = STR(DEFAULT_GIT_PORT);
 236        char *ep;
 237        struct hostent *he;
 238        struct sockaddr_in sa;
 239        char **ap;
 240        unsigned int nport;
 241        int cnt;
 242
 243        get_host_and_port(&host, &port);
 244
 245        if (flags & CONNECT_VERBOSE)
 246                fprintf(stderr, "Looking up %s ... ", host);
 247
 248        he = gethostbyname(host);
 249        if (!he)
 250                die("Unable to look up %s (%s)", host, hstrerror(h_errno));
 251        nport = strtoul(port, &ep, 10);
 252        if ( ep == port || *ep ) {
 253                /* Not numeric */
 254                struct servent *se = getservbyname(port,"tcp");
 255                if ( !se )
 256                        die("Unknown port %s", port);
 257                nport = se->s_port;
 258        }
 259
 260        if (flags & CONNECT_VERBOSE)
 261                fprintf(stderr, "done.\nConnecting to %s (port %s) ... ", host, port);
 262
 263        for (cnt = 0, ap = he->h_addr_list; *ap; ap++, cnt++) {
 264                memset(&sa, 0, sizeof sa);
 265                sa.sin_family = he->h_addrtype;
 266                sa.sin_port = htons(nport);
 267                memcpy(&sa.sin_addr, *ap, he->h_length);
 268
 269                sockfd = socket(he->h_addrtype, SOCK_STREAM, 0);
 270                if ((sockfd < 0) ||
 271                    connect(sockfd, (struct sockaddr *)&sa, sizeof sa) < 0) {
 272                        strbuf_addf(&error_message, "%s[%d: %s]: errno=%s\n",
 273                                host,
 274                                cnt,
 275                                inet_ntoa(*(struct in_addr *)&sa.sin_addr),
 276                                strerror(errno));
 277                        if (0 <= sockfd)
 278                                close(sockfd);
 279                        sockfd = -1;
 280                        continue;
 281                }
 282                if (flags & CONNECT_VERBOSE)
 283                        fprintf(stderr, "%s ",
 284                                inet_ntoa(*(struct in_addr *)&sa.sin_addr));
 285                break;
 286        }
 287
 288        if (sockfd < 0)
 289                die("unable to connect to %s:\n%s", host, error_message.buf);
 290
 291        if (flags & CONNECT_VERBOSE)
 292                fprintf(stderr, "done.\n");
 293
 294        return sockfd;
 295}
 296
 297#endif /* NO_IPV6 */
 298
 299
 300static void git_tcp_connect(int fd[2], char *host, int flags)
 301{
 302        int sockfd = git_tcp_connect_sock(host, flags);
 303
 304        fd[0] = sockfd;
 305        fd[1] = dup(sockfd);
 306}
 307
 308
 309static char *git_proxy_command;
 310
 311static int git_proxy_command_options(const char *var, const char *value,
 312                void *cb)
 313{
 314        if (!strcmp(var, "core.gitproxy")) {
 315                const char *for_pos;
 316                int matchlen = -1;
 317                int hostlen;
 318                const char *rhost_name = cb;
 319                int rhost_len = strlen(rhost_name);
 320
 321                if (git_proxy_command)
 322                        return 0;
 323                if (!value)
 324                        return config_error_nonbool(var);
 325                /* [core]
 326                 * ;# matches www.kernel.org as well
 327                 * gitproxy = netcatter-1 for kernel.org
 328                 * gitproxy = netcatter-2 for sample.xz
 329                 * gitproxy = netcatter-default
 330                 */
 331                for_pos = strstr(value, " for ");
 332                if (!for_pos)
 333                        /* matches everybody */
 334                        matchlen = strlen(value);
 335                else {
 336                        hostlen = strlen(for_pos + 5);
 337                        if (rhost_len < hostlen)
 338                                matchlen = -1;
 339                        else if (!strncmp(for_pos + 5,
 340                                          rhost_name + rhost_len - hostlen,
 341                                          hostlen) &&
 342                                 ((rhost_len == hostlen) ||
 343                                  rhost_name[rhost_len - hostlen -1] == '.'))
 344                                matchlen = for_pos - value;
 345                        else
 346                                matchlen = -1;
 347                }
 348                if (0 <= matchlen) {
 349                        /* core.gitproxy = none for kernel.org */
 350                        if (matchlen == 4 &&
 351                            !memcmp(value, "none", 4))
 352                                matchlen = 0;
 353                        git_proxy_command = xmemdupz(value, matchlen);
 354                }
 355                return 0;
 356        }
 357
 358        return git_default_config(var, value, cb);
 359}
 360
 361static int git_use_proxy(const char *host)
 362{
 363        git_proxy_command = getenv("GIT_PROXY_COMMAND");
 364        git_config(git_proxy_command_options, (void*)host);
 365        return (git_proxy_command && *git_proxy_command);
 366}
 367
 368static struct child_process *git_proxy_connect(int fd[2], char *host)
 369{
 370        const char *port = STR(DEFAULT_GIT_PORT);
 371        const char **argv;
 372        struct child_process *proxy;
 373
 374        get_host_and_port(&host, &port);
 375
 376        argv = xmalloc(sizeof(*argv) * 4);
 377        argv[0] = git_proxy_command;
 378        argv[1] = host;
 379        argv[2] = port;
 380        argv[3] = NULL;
 381        proxy = xcalloc(1, sizeof(*proxy));
 382        proxy->argv = argv;
 383        proxy->in = -1;
 384        proxy->out = -1;
 385        if (start_command(proxy))
 386                die("cannot start proxy %s", argv[0]);
 387        fd[0] = proxy->out; /* read from proxy stdout */
 388        fd[1] = proxy->in;  /* write to proxy stdin */
 389        return proxy;
 390}
 391
 392#define MAX_CMD_LEN 1024
 393
 394static char *get_port(char *host)
 395{
 396        char *end;
 397        char *p = strchr(host, ':');
 398
 399        if (p) {
 400                long port = strtol(p + 1, &end, 10);
 401                if (end != p + 1 && *end == '\0' && 0 <= port && port < 65536) {
 402                        *p = '\0';
 403                        return p+1;
 404                }
 405        }
 406
 407        return NULL;
 408}
 409
 410static struct child_process no_fork;
 411
 412/*
 413 * This returns a dummy child_process if the transport protocol does not
 414 * need fork(2), or a struct child_process object if it does.  Once done,
 415 * finish the connection with finish_connect() with the value returned from
 416 * this function (it is safe to call finish_connect() with NULL to support
 417 * the former case).
 418 *
 419 * If it returns, the connect is successful; it just dies on errors (this
 420 * will hopefully be changed in a libification effort, to return NULL when
 421 * the connection failed).
 422 */
 423struct child_process *git_connect(int fd[2], const char *url_orig,
 424                                  const char *prog, int flags)
 425{
 426        char *url;
 427        char *host, *path;
 428        char *end;
 429        int c;
 430        struct child_process *conn = &no_fork;
 431        enum protocol protocol = PROTO_LOCAL;
 432        int free_path = 0;
 433        char *port = NULL;
 434        const char **arg;
 435        struct strbuf cmd;
 436
 437        /* Without this we cannot rely on waitpid() to tell
 438         * what happened to our children.
 439         */
 440        signal(SIGCHLD, SIG_DFL);
 441
 442        if (is_url(url_orig))
 443                url = url_decode(url_orig);
 444        else
 445                url = xstrdup(url_orig);
 446
 447        host = strstr(url, "://");
 448        if (host) {
 449                *host = '\0';
 450                protocol = get_protocol(url);
 451                host += 3;
 452                c = '/';
 453        } else {
 454                host = url;
 455                c = ':';
 456        }
 457
 458        /*
 459         * Don't do destructive transforms with git:// as that
 460         * protocol code does '[]' unwrapping of its own.
 461         */
 462        if (host[0] == '[') {
 463                end = strchr(host + 1, ']');
 464                if (end) {
 465                        if (protocol != PROTO_GIT) {
 466                                *end = 0;
 467                                host++;
 468                        }
 469                        end++;
 470                } else
 471                        end = host;
 472        } else
 473                end = host;
 474
 475        path = strchr(end, c);
 476        if (path && !has_dos_drive_prefix(end)) {
 477                if (c == ':') {
 478                        protocol = PROTO_SSH;
 479                        *path++ = '\0';
 480                }
 481        } else
 482                path = end;
 483
 484        if (!path || !*path)
 485                die("No path specified. See 'man git-pull' for valid url syntax");
 486
 487        /*
 488         * null-terminate hostname and point path to ~ for URL's like this:
 489         *    ssh://host.xz/~user/repo
 490         */
 491        if (protocol != PROTO_LOCAL && host != url) {
 492                char *ptr = path;
 493                if (path[1] == '~')
 494                        path++;
 495                else {
 496                        path = xstrdup(ptr);
 497                        free_path = 1;
 498                }
 499
 500                *ptr = '\0';
 501        }
 502
 503        /*
 504         * Add support for ssh port: ssh://host.xy:<port>/...
 505         */
 506        if (protocol == PROTO_SSH && host != url)
 507                port = get_port(host);
 508
 509        if (protocol == PROTO_GIT) {
 510                /* These underlying connection commands die() if they
 511                 * cannot connect.
 512                 */
 513                char *target_host = xstrdup(host);
 514                if (git_use_proxy(host))
 515                        conn = git_proxy_connect(fd, host);
 516                else
 517                        git_tcp_connect(fd, host, flags);
 518                /*
 519                 * Separate original protocol components prog and path
 520                 * from extended host header with a NUL byte.
 521                 *
 522                 * Note: Do not add any other headers here!  Doing so
 523                 * will cause older git-daemon servers to crash.
 524                 */
 525                packet_write(fd[1],
 526                             "%s %s%chost=%s%c",
 527                             prog, path, 0,
 528                             target_host, 0);
 529                free(target_host);
 530                free(url);
 531                if (free_path)
 532                        free(path);
 533                return conn;
 534        }
 535
 536        conn = xcalloc(1, sizeof(*conn));
 537
 538        strbuf_init(&cmd, MAX_CMD_LEN);
 539        strbuf_addstr(&cmd, prog);
 540        strbuf_addch(&cmd, ' ');
 541        sq_quote_buf(&cmd, path);
 542        if (cmd.len >= MAX_CMD_LEN)
 543                die("command line too long");
 544
 545        conn->in = conn->out = -1;
 546        conn->argv = arg = xcalloc(7, sizeof(*arg));
 547        if (protocol == PROTO_SSH) {
 548                const char *ssh = getenv("GIT_SSH");
 549                int putty = ssh && strcasestr(ssh, "plink");
 550                if (!ssh) ssh = "ssh";
 551
 552                *arg++ = ssh;
 553                if (putty && !strcasestr(ssh, "tortoiseplink"))
 554                        *arg++ = "-batch";
 555                if (port) {
 556                        /* P is for PuTTY, p is for OpenSSH */
 557                        *arg++ = putty ? "-P" : "-p";
 558                        *arg++ = port;
 559                }
 560                *arg++ = host;
 561        }
 562        else {
 563                /* remove repo-local variables from the environment */
 564                conn->env = local_repo_env;
 565                conn->use_shell = 1;
 566        }
 567        *arg++ = cmd.buf;
 568        *arg = NULL;
 569
 570        if (start_command(conn))
 571                die("unable to fork");
 572
 573        fd[0] = conn->out; /* read from child's stdout */
 574        fd[1] = conn->in;  /* write to child's stdin */
 575        strbuf_release(&cmd);
 576        free(url);
 577        if (free_path)
 578                free(path);
 579        return conn;
 580}
 581
 582int git_connection_is_socket(struct child_process *conn)
 583{
 584        return conn == &no_fork;
 585}
 586
 587int finish_connect(struct child_process *conn)
 588{
 589        int code;
 590        if (!conn || git_connection_is_socket(conn))
 591                return 0;
 592
 593        code = finish_command(conn);
 594        free(conn->argv);
 595        free(conn);
 596        return code;
 597}
 598
 599char *git_getpass(const char *prompt)
 600{
 601        const char *askpass;
 602        struct child_process pass;
 603        const char *args[3];
 604        static struct strbuf buffer = STRBUF_INIT;
 605
 606        askpass = getenv("GIT_ASKPASS");
 607        if (!askpass)
 608                askpass = askpass_program;
 609        if (!askpass)
 610                askpass = getenv("SSH_ASKPASS");
 611        if (!askpass || !(*askpass)) {
 612                char *result = getpass(prompt);
 613                if (!result)
 614                        die_errno("Could not read password");
 615                return result;
 616        }
 617
 618        args[0] = askpass;
 619        args[1] = prompt;
 620        args[2] = NULL;
 621
 622        memset(&pass, 0, sizeof(pass));
 623        pass.argv = args;
 624        pass.out = -1;
 625
 626        if (start_command(&pass))
 627                exit(1);
 628
 629        strbuf_reset(&buffer);
 630        if (strbuf_read(&buffer, pass.out, 20) < 0)
 631                die("failed to read password from %s\n", askpass);
 632
 633        close(pass.out);
 634
 635        if (finish_command(&pass))
 636                exit(1);
 637
 638        strbuf_setlen(&buffer, strcspn(buffer.buf, "\r\n"));
 639
 640        return buffer.buf;
 641}