Andrew's git - gitweb.git/blob

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