8e08f057dd6536b06d1ee017e4733ad1585e782e
   1#include "cache.h"
   2#include "refs.h"
   3#include "pkt-line.h"
   4#include "object.h"
   5#include "tag.h"
   6#include "exec_cmd.h"
   7#include "run-command.h"
   8#include "string-list.h"
   9
  10static const char content_type[] = "Content-Type";
  11static const char content_length[] = "Content-Length";
  12static const char last_modified[] = "Last-Modified";
  13static int getanyfile = 1;
  14
  15static struct string_list *query_params;
  16
  17struct rpc_service {
  18        const char *name;
  19        const char *config_name;
  20        signed enabled : 2;
  21};
  22
  23static struct rpc_service rpc_service[] = {
  24        { "upload-pack", "uploadpack", 1 },
  25        { "receive-pack", "receivepack", -1 },
  26};
  27
  28static int decode_char(const char *q)
  29{
  30        int i;
  31        unsigned char val = 0;
  32        for (i = 0; i < 2; i++) {
  33                unsigned char c = *q++;
  34                val <<= 4;
  35                if (c >= '0' && c <= '9')
  36                        val += c - '0';
  37                else if (c >= 'a' && c <= 'f')
  38                        val += c - 'a' + 10;
  39                else if (c >= 'A' && c <= 'F')
  40                        val += c - 'A' + 10;
  41                else
  42                        return -1;
  43        }
  44        return val;
  45}
  46
  47static char *decode_parameter(const char **query, int is_name)
  48{
  49        const char *q = *query;
  50        struct strbuf out;
  51
  52        strbuf_init(&out, 16);
  53        do {
  54                unsigned char c = *q;
  55
  56                if (!c)
  57                        break;
  58                if (c == '&' || (is_name && c == '=')) {
  59                        q++;
  60                        break;
  61                }
  62
  63                if (c == '%') {
  64                        int val = decode_char(q + 1);
  65                        if (0 <= val) {
  66                                strbuf_addch(&out, val);
  67                                q += 3;
  68                                continue;
  69                        }
  70                }
  71
  72                if (c == '+')
  73                        strbuf_addch(&out, ' ');
  74                else
  75                        strbuf_addch(&out, c);
  76                q++;
  77        } while (1);
  78        *query = q;
  79        return strbuf_detach(&out, NULL);
  80}
  81
  82static struct string_list *get_parameters(void)
  83{
  84        if (!query_params) {
  85                const char *query = getenv("QUERY_STRING");
  86
  87                query_params = xcalloc(1, sizeof(*query_params));
  88                while (query && *query) {
  89                        char *name = decode_parameter(&query, 1);
  90                        char *value = decode_parameter(&query, 0);
  91                        struct string_list_item *i;
  92
  93                        i = string_list_lookup(name, query_params);
  94                        if (!i)
  95                                i = string_list_insert(name, query_params);
  96                        else
  97                                free(i->util);
  98                        i->util = value;
  99                }
 100        }
 101        return query_params;
 102}
 103
 104static const char *get_parameter(const char *name)
 105{
 106        struct string_list_item *i;
 107        i = string_list_lookup(name, get_parameters());
 108        return i ? i->util : NULL;
 109}
 110
 111static void format_write(int fd, const char *fmt, ...)
 112{
 113        static char buffer[1024];
 114
 115        va_list args;
 116        unsigned n;
 117
 118        va_start(args, fmt);
 119        n = vsnprintf(buffer, sizeof(buffer), fmt, args);
 120        va_end(args);
 121        if (n >= sizeof(buffer))
 122                die("protocol error: impossibly long line");
 123
 124        safe_write(fd, buffer, n);
 125}
 126
 127static void http_status(unsigned code, const char *msg)
 128{
 129        format_write(1, "Status: %u %s\r\n", code, msg);
 130}
 131
 132static void hdr_str(const char *name, const char *value)
 133{
 134        format_write(1, "%s: %s\r\n", name, value);
 135}
 136
 137static void hdr_int(const char *name, uintmax_t value)
 138{
 139        format_write(1, "%s: %" PRIuMAX "\r\n", name, value);
 140}
 141
 142static void hdr_date(const char *name, unsigned long when)
 143{
 144        const char *value = show_date(when, 0, DATE_RFC2822);
 145        hdr_str(name, value);
 146}
 147
 148static void hdr_nocache(void)
 149{
 150        hdr_str("Expires", "Fri, 01 Jan 1980 00:00:00 GMT");
 151        hdr_str("Pragma", "no-cache");
 152        hdr_str("Cache-Control", "no-cache, max-age=0, must-revalidate");
 153}
 154
 155static void hdr_cache_forever(void)
 156{
 157        unsigned long now = time(NULL);
 158        hdr_date("Date", now);
 159        hdr_date("Expires", now + 31536000);
 160        hdr_str("Cache-Control", "public, max-age=31536000");
 161}
 162
 163static void end_headers(void)
 164{
 165        safe_write(1, "\r\n", 2);
 166}
 167
 168static NORETURN void not_found(const char *err, ...)
 169{
 170        va_list params;
 171
 172        http_status(404, "Not Found");
 173        hdr_nocache();
 174        end_headers();
 175
 176        va_start(params, err);
 177        if (err && *err)
 178                vfprintf(stderr, err, params);
 179        va_end(params);
 180        exit(0);
 181}
 182
 183static NORETURN void forbidden(const char *err, ...)
 184{
 185        va_list params;
 186
 187        http_status(403, "Forbidden");
 188        hdr_nocache();
 189        end_headers();
 190
 191        va_start(params, err);
 192        if (err && *err)
 193                vfprintf(stderr, err, params);
 194        va_end(params);
 195        exit(0);
 196}
 197
 198static void select_getanyfile(void)
 199{
 200        if (!getanyfile)
 201                forbidden("Unsupported service: getanyfile");
 202}
 203
 204static void send_strbuf(const char *type, struct strbuf *buf)
 205{
 206        hdr_int(content_length, buf->len);
 207        hdr_str(content_type, type);
 208        end_headers();
 209        safe_write(1, buf->buf, buf->len);
 210}
 211
 212static void send_local_file(const char *the_type, const char *name)
 213{
 214        const char *p = git_path("%s", name);
 215        size_t buf_alloc = 8192;
 216        char *buf = xmalloc(buf_alloc);
 217        int fd;
 218        struct stat sb;
 219
 220        fd = open(p, O_RDONLY);
 221        if (fd < 0)
 222                not_found("Cannot open '%s': %s", p, strerror(errno));
 223        if (fstat(fd, &sb) < 0)
 224                die_errno("Cannot stat '%s'", p);
 225
 226        hdr_int(content_length, sb.st_size);
 227        hdr_str(content_type, the_type);
 228        hdr_date(last_modified, sb.st_mtime);
 229        end_headers();
 230
 231        for (;;) {
 232                ssize_t n = xread(fd, buf, buf_alloc);
 233                if (n < 0)
 234                        die_errno("Cannot read '%s'", p);
 235                if (!n)
 236                        break;
 237                safe_write(1, buf, n);
 238        }
 239        close(fd);
 240        free(buf);
 241}
 242
 243static void get_text_file(char *name)
 244{
 245        select_getanyfile();
 246        hdr_nocache();
 247        send_local_file("text/plain", name);
 248}
 249
 250static void get_loose_object(char *name)
 251{
 252        select_getanyfile();
 253        hdr_cache_forever();
 254        send_local_file("application/x-git-loose-object", name);
 255}
 256
 257static void get_pack_file(char *name)
 258{
 259        select_getanyfile();
 260        hdr_cache_forever();
 261        send_local_file("application/x-git-packed-objects", name);
 262}
 263
 264static void get_idx_file(char *name)
 265{
 266        select_getanyfile();
 267        hdr_cache_forever();
 268        send_local_file("application/x-git-packed-objects-toc", name);
 269}
 270
 271static int http_config(const char *var, const char *value, void *cb)
 272{
 273        if (!strcmp(var, "http.getanyfile")) {
 274                getanyfile = git_config_bool(var, value);
 275                return 0;
 276        }
 277
 278        if (!prefixcmp(var, "http.")) {
 279                int i;
 280
 281                for (i = 0; i < ARRAY_SIZE(rpc_service); i++) {
 282                        struct rpc_service *svc = &rpc_service[i];
 283                        if (!strcmp(var + 5, svc->config_name)) {
 284                                svc->enabled = git_config_bool(var, value);
 285                                return 0;
 286                        }
 287                }
 288        }
 289
 290        /* we are not interested in parsing any other configuration here */
 291        return 0;
 292}
 293
 294static struct rpc_service *select_service(const char *name)
 295{
 296        struct rpc_service *svc = NULL;
 297        int i;
 298
 299        if (prefixcmp(name, "git-"))
 300                forbidden("Unsupported service: '%s'", name);
 301
 302        for (i = 0; i < ARRAY_SIZE(rpc_service); i++) {
 303                struct rpc_service *s = &rpc_service[i];
 304                if (!strcmp(s->name, name + 4)) {
 305                        svc = s;
 306                        break;
 307                }
 308        }
 309
 310        if (!svc)
 311                forbidden("Unsupported service: '%s'", name);
 312
 313        if (svc->enabled < 0) {
 314                const char *user = getenv("REMOTE_USER");
 315                svc->enabled = (user && *user) ? 1 : 0;
 316        }
 317        if (!svc->enabled)
 318                forbidden("Service not enabled: '%s'", svc->name);
 319        return svc;
 320}
 321
 322static void inflate_request(const char *prog_name, int out)
 323{
 324        z_stream stream;
 325        unsigned char in_buf[8192];
 326        unsigned char out_buf[8192];
 327        unsigned long cnt = 0;
 328        int ret;
 329
 330        memset(&stream, 0, sizeof(stream));
 331        ret = inflateInit2(&stream, (15 + 16));
 332        if (ret != Z_OK)
 333                die("cannot start zlib inflater, zlib err %d", ret);
 334
 335        while (1) {
 336                ssize_t n = xread(0, in_buf, sizeof(in_buf));
 337                if (n <= 0)
 338                        die("request ended in the middle of the gzip stream");
 339
 340                stream.next_in = in_buf;
 341                stream.avail_in = n;
 342
 343                while (0 < stream.avail_in) {
 344                        int ret;
 345
 346                        stream.next_out = out_buf;
 347                        stream.avail_out = sizeof(out_buf);
 348
 349                        ret = inflate(&stream, Z_NO_FLUSH);
 350                        if (ret != Z_OK && ret != Z_STREAM_END)
 351                                die("zlib error inflating request, result %d", ret);
 352
 353                        n = stream.total_out - cnt;
 354                        if (write_in_full(out, out_buf, n) != n)
 355                                die("%s aborted reading request", prog_name);
 356                        cnt += n;
 357
 358                        if (ret == Z_STREAM_END)
 359                                goto done;
 360                }
 361        }
 362
 363done:
 364        inflateEnd(&stream);
 365        close(out);
 366}
 367
 368static void run_service(const char **argv)
 369{
 370        const char *encoding = getenv("HTTP_CONTENT_ENCODING");
 371        const char *user = getenv("REMOTE_USER");
 372        const char *host = getenv("REMOTE_ADDR");
 373        char *env[3];
 374        struct strbuf buf = STRBUF_INIT;
 375        int gzipped_request = 0;
 376        struct child_process cld;
 377
 378        if (encoding && !strcmp(encoding, "gzip"))
 379                gzipped_request = 1;
 380        else if (encoding && !strcmp(encoding, "x-gzip"))
 381                gzipped_request = 1;
 382
 383        if (!user || !*user)
 384                user = "anonymous";
 385        if (!host || !*host)
 386                host = "(none)";
 387
 388        memset(&env, 0, sizeof(env));
 389        strbuf_addf(&buf, "GIT_COMMITTER_NAME=%s", user);
 390        env[0] = strbuf_detach(&buf, NULL);
 391
 392        strbuf_addf(&buf, "GIT_COMMITTER_EMAIL=%s@http.%s", user, host);
 393        env[1] = strbuf_detach(&buf, NULL);
 394        env[2] = NULL;
 395
 396        memset(&cld, 0, sizeof(cld));
 397        cld.argv = argv;
 398        cld.env = (const char *const *)env;
 399        if (gzipped_request)
 400                cld.in = -1;
 401        cld.git_cmd = 1;
 402        if (start_command(&cld))
 403                exit(1);
 404
 405        close(1);
 406        if (gzipped_request)
 407                inflate_request(argv[0], cld.in);
 408        else
 409                close(0);
 410
 411        if (finish_command(&cld))
 412                exit(1);
 413        free(env[0]);
 414        free(env[1]);
 415        strbuf_release(&buf);
 416}
 417
 418static int show_text_ref(const char *name, const unsigned char *sha1,
 419        int flag, void *cb_data)
 420{
 421        struct strbuf *buf = cb_data;
 422        struct object *o = parse_object(sha1);
 423        if (!o)
 424                return 0;
 425
 426        strbuf_addf(buf, "%s\t%s\n", sha1_to_hex(sha1), name);
 427        if (o->type == OBJ_TAG) {
 428                o = deref_tag(o, name, 0);
 429                if (!o)
 430                        return 0;
 431                strbuf_addf(buf, "%s\t%s^{}\n", sha1_to_hex(o->sha1), name);
 432        }
 433        return 0;
 434}
 435
 436static void get_info_refs(char *arg)
 437{
 438        const char *service_name = get_parameter("service");
 439        struct strbuf buf = STRBUF_INIT;
 440
 441        hdr_nocache();
 442
 443        if (service_name) {
 444                const char *argv[] = {NULL /* service name */,
 445                        "--stateless-rpc", "--advertise-refs",
 446                        ".", NULL};
 447                struct rpc_service *svc = select_service(service_name);
 448
 449                strbuf_addf(&buf, "application/x-git-%s-advertisement",
 450                        svc->name);
 451                hdr_str(content_type, buf.buf);
 452                end_headers();
 453
 454                packet_write(1, "# service=git-%s\n", svc->name);
 455                packet_flush(1);
 456
 457                argv[0] = svc->name;
 458                run_service(argv);
 459
 460        } else {
 461                select_getanyfile();
 462                for_each_ref(show_text_ref, &buf);
 463                send_strbuf("text/plain", &buf);
 464        }
 465        strbuf_release(&buf);
 466}
 467
 468static void get_info_packs(char *arg)
 469{
 470        size_t objdirlen = strlen(get_object_directory());
 471        struct strbuf buf = STRBUF_INIT;
 472        struct packed_git *p;
 473        size_t cnt = 0;
 474
 475        select_getanyfile();
 476        prepare_packed_git();
 477        for (p = packed_git; p; p = p->next) {
 478                if (p->pack_local)
 479                        cnt++;
 480        }
 481
 482        strbuf_grow(&buf, cnt * 53 + 2);
 483        for (p = packed_git; p; p = p->next) {
 484                if (p->pack_local)
 485                        strbuf_addf(&buf, "P %s\n", p->pack_name + objdirlen + 6);
 486        }
 487        strbuf_addch(&buf, '\n');
 488
 489        hdr_nocache();
 490        send_strbuf("text/plain; charset=utf-8", &buf);
 491        strbuf_release(&buf);
 492}
 493
 494static void check_content_type(const char *accepted_type)
 495{
 496        const char *actual_type = getenv("CONTENT_TYPE");
 497
 498        if (!actual_type)
 499                actual_type = "";
 500
 501        if (strcmp(actual_type, accepted_type)) {
 502                http_status(415, "Unsupported Media Type");
 503                hdr_nocache();
 504                end_headers();
 505                format_write(1,
 506                        "Expected POST with Content-Type '%s',"
 507                        " but received '%s' instead.\n",
 508                        accepted_type, actual_type);
 509                exit(0);
 510        }
 511}
 512
 513static void service_rpc(char *service_name)
 514{
 515        const char *argv[] = {NULL, "--stateless-rpc", ".", NULL};
 516        struct rpc_service *svc = select_service(service_name);
 517        struct strbuf buf = STRBUF_INIT;
 518
 519        strbuf_reset(&buf);
 520        strbuf_addf(&buf, "application/x-git-%s-request", svc->name);
 521        check_content_type(buf.buf);
 522
 523        hdr_nocache();
 524
 525        strbuf_reset(&buf);
 526        strbuf_addf(&buf, "application/x-git-%s-result", svc->name);
 527        hdr_str(content_type, buf.buf);
 528
 529        end_headers();
 530
 531        argv[0] = svc->name;
 532        run_service(argv);
 533        strbuf_release(&buf);
 534}
 535
 536static NORETURN void die_webcgi(const char *err, va_list params)
 537{
 538        char buffer[1000];
 539
 540        http_status(500, "Internal Server Error");
 541        hdr_nocache();
 542        end_headers();
 543
 544        vsnprintf(buffer, sizeof(buffer), err, params);
 545        fprintf(stderr, "fatal: %s\n", buffer);
 546        exit(0);
 547}
 548
 549static char* getdir(void)
 550{
 551        struct strbuf buf = STRBUF_INIT;
 552        char *pathinfo = getenv("PATH_INFO");
 553        char *root = getenv("GIT_PROJECT_ROOT");
 554        char *path = getenv("PATH_TRANSLATED");
 555
 556        if (root && *root) {
 557                if (!pathinfo || !*pathinfo)
 558                        die("GIT_PROJECT_ROOT is set but PATH_INFO is not");
 559                if (daemon_avoid_alias(pathinfo))
 560                        die("'%s': aliased", pathinfo);
 561                strbuf_addstr(&buf, root);
 562                if (buf.buf[buf.len - 1] != '/')
 563                        strbuf_addch(&buf, '/');
 564                if (pathinfo[0] == '/')
 565                        pathinfo++;
 566                strbuf_addstr(&buf, pathinfo);
 567                return strbuf_detach(&buf, NULL);
 568        } else if (path && *path) {
 569                return xstrdup(path);
 570        } else
 571                die("No GIT_PROJECT_ROOT or PATH_TRANSLATED from server");
 572        return NULL;
 573}
 574
 575static struct service_cmd {
 576        const char *method;
 577        const char *pattern;
 578        void (*imp)(char *);
 579} services[] = {
 580        {"GET", "/HEAD$", get_text_file},
 581        {"GET", "/info/refs$", get_info_refs},
 582        {"GET", "/objects/info/alternates$", get_text_file},
 583        {"GET", "/objects/info/http-alternates$", get_text_file},
 584        {"GET", "/objects/info/packs$", get_info_packs},
 585        {"GET", "/objects/[0-9a-f]{2}/[0-9a-f]{38}$", get_loose_object},
 586        {"GET", "/objects/pack/pack-[0-9a-f]{40}\\.pack$", get_pack_file},
 587        {"GET", "/objects/pack/pack-[0-9a-f]{40}\\.idx$", get_idx_file},
 588
 589        {"POST", "/git-upload-pack$", service_rpc},
 590        {"POST", "/git-receive-pack$", service_rpc}
 591};
 592
 593int main(int argc, char **argv)
 594{
 595        char *method = getenv("REQUEST_METHOD");
 596        char *dir;
 597        struct service_cmd *cmd = NULL;
 598        char *cmd_arg = NULL;
 599        int i;
 600
 601        git_extract_argv0_path(argv[0]);
 602        set_die_routine(die_webcgi);
 603
 604        if (!method)
 605                die("No REQUEST_METHOD from server");
 606        if (!strcmp(method, "HEAD"))
 607                method = "GET";
 608        dir = getdir();
 609
 610        for (i = 0; i < ARRAY_SIZE(services); i++) {
 611                struct service_cmd *c = &services[i];
 612                regex_t re;
 613                regmatch_t out[1];
 614
 615                if (regcomp(&re, c->pattern, REG_EXTENDED))
 616                        die("Bogus regex in service table: %s", c->pattern);
 617                if (!regexec(&re, dir, 1, out, 0)) {
 618                        size_t n;
 619
 620                        if (strcmp(method, c->method)) {
 621                                const char *proto = getenv("SERVER_PROTOCOL");
 622                                if (proto && !strcmp(proto, "HTTP/1.1"))
 623                                        http_status(405, "Method Not Allowed");
 624                                else
 625                                        http_status(400, "Bad Request");
 626                                hdr_nocache();
 627                                end_headers();
 628                                return 0;
 629                        }
 630
 631                        cmd = c;
 632                        n = out[0].rm_eo - out[0].rm_so;
 633                        cmd_arg = xmalloc(n);
 634                        memcpy(cmd_arg, dir + out[0].rm_so + 1, n-1);
 635                        cmd_arg[n-1] = '\0';
 636                        dir[out[0].rm_so] = 0;
 637                        break;
 638                }
 639                regfree(&re);
 640        }
 641
 642        if (!cmd)
 643                not_found("Request not supported: '%s'", dir);
 644
 645        setup_path();
 646        if (!enter_repo(dir, 0))
 647                not_found("Not a git repository: '%s'", dir);
 648
 649        git_config(http_config, NULL);
 650        cmd->imp(cmd_arg);
 651        return 0;
 652}