libexec/got-read-gitconfig/got-read-gitconfig.c

   1 /*
   2  * Copyright (c) 2019 Stefan Sperling <stsp@openbsd.org>
   3  *
   4  * Permission to use, copy, modify, and distribute this software for any
   5  * purpose with or without fee is hereby granted, provided that the above
   6  * copyright notice and this permission notice appear in all copies.
   7  *
   8  * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
   9  * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
  10  * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
  11  * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
  12  * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
  13  * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
  14  * OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
  15  */
  16
  17 #include <sys/types.h>
  18 #include <sys/queue.h>
  19 #include <sys/uio.h>
  20 #include <sys/time.h>
  21
  22 #include <err.h>
  23 #include <stdint.h>
  24 #include <limits.h>
  25 #include <signal.h>
  26 #include <stdio.h>
  27 #include <stdlib.h>
  28 #include <string.h>
  29 #include <unistd.h>
  30 #include <zlib.h>
  31
  32 #include "got_compat.h"
  33
  34 #include "got_error.h"
  35 #include "got_object.h"
  36 #include "got_repository.h"
  37
  38 #include "got_lib_delta.h"
  39 #include "got_lib_hash.h"
  40 #include "got_lib_object.h"
  41 #include "got_lib_privsep.h"
  42 #include "got_lib_gitconfig.h"
  43
  44 static volatile sig_atomic_t sigint_received;
  45
  46 static void
  47 catch_sigint(int signo)
  48 {
  49         sigint_received = 1;
  50 }
  51
  52 static const struct got_error *
  53 send_gitconfig_int(struct imsgbuf *ibuf, int value)
  54 {
  55         if (imsg_compose(ibuf, GOT_IMSG_GITCONFIG_INT_VAL, 0, 0, -1,
  56             &value, sizeof(value)) == -1)
  57                 return got_error_from_errno("imsg_compose GITCONFIG_INT_VAL");
  58
  59         return got_privsep_flush_imsg(ibuf);
  60 }
  61
  62 static const struct got_error *
  63 gitconfig_num_request(struct imsgbuf *ibuf, struct got_gitconfig *gitconfig,
  64     const char *section, const char *tag, int def)
  65 {
  66         int value;
  67
  68         if (gitconfig == NULL)
  69                 return got_error(GOT_ERR_PRIVSEP_MSG);
  70
  71         value = got_gitconfig_get_num(gitconfig, section, tag, def);
  72         return send_gitconfig_int(ibuf, value);
  73 }
  74
  75 static const struct got_error *
  76 send_gitconfig_str(struct imsgbuf *ibuf, const char *value)
  77 {
  78         size_t len = value ? strlen(value) : 0;
  79
  80         if (imsg_compose(ibuf, GOT_IMSG_GITCONFIG_STR_VAL, 0, 0, -1,
  81             value, len) == -1)
  82                 return got_error_from_errno("imsg_compose GITCONFIG_STR_VAL");
  83
  84         return got_privsep_flush_imsg(ibuf);
  85 }
  86
  87 static const struct got_error *
  88 send_gitconfig_pair(struct imsgbuf *ibuf, const char *key, const char *val)
  89 {
  90         struct ibuf *wbuf;
  91         size_t klen = key ? strlen(key) : 0;
  92         size_t vlen = val ? strlen(val) : 0;
  93         size_t tot = sizeof(klen) + sizeof(vlen) + klen + vlen;
  94
  95         if (tot > MAX_IMSGSIZE - IMSG_HEADER_SIZE)
  96                 return got_error(GOT_ERR_NO_SPACE);
  97
  98         wbuf = imsg_create(ibuf, GOT_IMSG_GITCONFIG_PAIR, 0, 0, tot);
  99         if (wbuf == NULL)
 100                 return got_error_from_errno("imsg_create GITCONFIG_PAIR");
 101
 102         /* Keep in sync with got_imsg_gitconfig_pair */
 103         if (imsg_add(wbuf, &klen, sizeof(klen)) == -1)
 104                 return got_error_from_errno("imsg_add GITCONFIG_PAIR");
 105         if (imsg_add(wbuf, &vlen, sizeof(vlen)) == -1)
 106                 return got_error_from_errno("imsg_add GITCONFIG_PAIR");
 107         if (imsg_add(wbuf, key, klen) == -1)
 108                 return got_error_from_errno("imsg_add GITCONFIG_PAIR");
 109         if (imsg_add(wbuf, val, vlen) == -1)
 110                 return got_error_from_errno("imsg_add GITCONFIG_PAIR");
 111
 112         imsg_close(ibuf, wbuf);
 113         return got_privsep_flush_imsg(ibuf);
 114 }
 115
 116 static const struct got_error *
 117 gitconfig_str_request(struct imsgbuf *ibuf, struct got_gitconfig *gitconfig,
 118     const char *section, const char *tag)
 119 {
 120         char *value;
 121
 122         if (gitconfig == NULL)
 123                 return got_error(GOT_ERR_PRIVSEP_MSG);
 124
 125         value = got_gitconfig_get_str(gitconfig, section, tag);
 126         return send_gitconfig_str(ibuf, value);
 127 }
 128
 129 static const struct got_error *
 130 send_gitconfig_remotes(struct imsgbuf *ibuf, struct got_remote_repo *remotes,
 131     int nremotes)
 132 {
 133         const struct got_error *err = NULL;
 134         struct got_imsg_remotes iremotes;
 135         int i;
 136
 137         iremotes.nremotes = nremotes;
 138         if (imsg_compose(ibuf, GOT_IMSG_GITCONFIG_REMOTES, 0, 0, -1,
 139             &iremotes, sizeof(iremotes)) == -1)
 140                 return got_error_from_errno("imsg_compose GITCONFIG_REMOTES");
 141
 142         err = got_privsep_flush_imsg(ibuf);
 143         if (err)
 144                 return err;
 145
 146         for (i = 0; i < nremotes; i++) {
 147                 struct got_imsg_remote iremote;
 148                 size_t len = sizeof(iremote);
 149                 struct ibuf *wbuf;
 150
 151                 iremote.mirror_references = remotes[i].mirror_references;
 152                 iremote.name_len = strlen(remotes[i].name);
 153                 len += iremote.name_len;
 154                 iremote.fetch_url_len = strlen(remotes[i].fetch_url);
 155                 len += iremote.fetch_url_len;
 156                 iremote.send_url_len = strlen(remotes[i].send_url);
 157                 len += iremote.send_url_len;
 158
 159                 wbuf = imsg_create(ibuf, GOT_IMSG_GITCONFIG_REMOTE, 0, 0, len);
 160                 if (wbuf == NULL)
 161                         return got_error_from_errno(
 162                             "imsg_create GITCONFIG_REMOTE");
 163
 164                 if (imsg_add(wbuf, &iremote, sizeof(iremote)) == -1)
 165                         return got_error_from_errno(
 166                             "imsg_add GITCONFIG_REMOTE");
 167
 168                 if (imsg_add(wbuf, remotes[i].name, iremote.name_len) == -1)
 169                         return got_error_from_errno(
 170                             "imsg_add GITCONFIG_REMOTE");
 171                 if (imsg_add(wbuf, remotes[i].fetch_url, iremote.fetch_url_len) == -1)
 172                         return got_error_from_errno(
 173                             "imsg_add GITCONFIG_REMOTE");
 174                 if (imsg_add(wbuf, remotes[i].send_url, iremote.send_url_len) == -1)
 175                         return got_error_from_errno(
 176                             "imsg_add GITCONFIG_REMOTE");
 177
 178                 imsg_close(ibuf, wbuf);
 179                 err = got_privsep_flush_imsg(ibuf);
 180                 if (err)
 181                         return err;
 182         }
 183
 184         return NULL;
 185 }
 186
 187 static int
 188 get_boolean_val(char *val)
 189 {
 190     return (strcasecmp(val, "true") == 0 ||
 191         strcasecmp(val, "on") == 0 ||
 192         strcasecmp(val, "yes") == 0 ||
 193         strcmp(val, "1") == 0);
 194 }
 195
 196 static int
 197 skip_node(struct got_gitconfig *gitconfig, struct got_gitconfig_list_node *node)
 198 {
 199         /*
 200          * Skip config nodes which do not describe remotes, and remotes
 201          * which do not have a fetch URL defined (as used by git-annex).
 202          */
 203         return (strncasecmp("remote \"", node->field, 8) != 0 ||
 204             got_gitconfig_get_str(gitconfig, node->field, "url") == NULL);
 205 }
 206
 207 static const struct got_error *
 208 gitconfig_remotes_request(struct imsgbuf *ibuf, struct got_gitconfig *gitconfig)
 209 {
 210         const struct got_error *err = NULL;
 211         struct got_gitconfig_list *sections;
 212         struct got_gitconfig_list_node *node;
 213         struct got_remote_repo *remotes = NULL;
 214         int nremotes = 0, i;
 215
 216         if (gitconfig == NULL)
 217                 return got_error(GOT_ERR_PRIVSEP_MSG);
 218
 219         err = got_gitconfig_get_section_list(&sections, gitconfig);
 220         if (err)
 221                 return err;
 222
 223         TAILQ_FOREACH(node, &sections->fields, link) {
 224                 if (skip_node(gitconfig, node))
 225                         continue;
 226                 nremotes++;
 227         }
 228
 229         if (nremotes == 0) {
 230                 err = send_gitconfig_remotes(ibuf, NULL, 0);
 231                 goto done;
 232         }
 233
 234         remotes = recallocarray(NULL, 0, nremotes, sizeof(*remotes));
 235         if (remotes == NULL) {
 236                 err = got_error_from_errno("recallocarray");
 237                 goto done;
 238         }
 239
 240         i = 0;
 241         TAILQ_FOREACH(node, &sections->fields, link) {
 242                 char *name, *end, *mirror;
 243
 244                 if (skip_node(gitconfig, node))
 245                         continue;
 246
 247                 name = strdup(node->field + 8);
 248                 if (name == NULL) {
 249                         err = got_error_from_errno("strdup");
 250                         goto done;
 251                 }
 252                 end = strrchr(name, '"');
 253                 if (end)
 254                         *end = '\0';
 255                 remotes[i].name = name;
 256
 257                 remotes[i].fetch_url = got_gitconfig_get_str(gitconfig,
 258                     node->field, "url");
 259
 260                 remotes[i].send_url = got_gitconfig_get_str(gitconfig,
 261                     node->field, "pushurl");
 262                 if (remotes[i].send_url == NULL)
 263                         remotes[i].send_url = remotes[i].fetch_url;
 264
 265                 remotes[i].mirror_references = 0;
 266                 mirror = got_gitconfig_get_str(gitconfig, node->field,
 267                     "mirror");
 268                 if (mirror != NULL && get_boolean_val(mirror))
 269                         remotes[i].mirror_references = 1;
 270
 271                 i++;
 272         }
 273
 274         err = send_gitconfig_remotes(ibuf, remotes, nremotes);
 275 done:
 276         for (i = 0; i < nremotes; i++)
 277                 free(remotes[i].name);
 278         free(remotes);
 279         got_gitconfig_free_list(sections);
 280         return err;
 281 }
 282
 283 static const struct got_error *
 284 gitconfig_owner_request(struct imsgbuf *ibuf, struct got_gitconfig *gitconfig)
 285 {
 286         char *value;
 287
 288         if (gitconfig == NULL)
 289                 return got_error(GOT_ERR_PRIVSEP_MSG);
 290
 291         value = got_gitconfig_get_str(gitconfig, "gotweb", "owner");
 292         if (value)
 293                 return send_gitconfig_str(ibuf, value);
 294         value = got_gitconfig_get_str(gitconfig, "gitweb", "owner");
 295         return send_gitconfig_str(ibuf, value);
 296 }
 297
 298 static const struct got_error *
 299 gitconfig_extensions_request(struct imsgbuf *ibuf,
 300     struct got_gitconfig *gitconfig)
 301 {
 302         const struct got_error *err = NULL;
 303         struct got_gitconfig_list *tags;
 304         struct got_gitconfig_list_node *node;
 305         int nextensions = 0;
 306         char *val;
 307
 308         if (gitconfig == NULL)
 309                 return got_error(GOT_ERR_PRIVSEP_MSG);
 310
 311         tags = got_gitconfig_get_tag_list(gitconfig, "extensions");
 312         if (tags == NULL)
 313                 return send_gitconfig_int(ibuf, 0);
 314
 315         TAILQ_FOREACH(node, &tags->fields, link)
 316                 nextensions++;
 317
 318         err = send_gitconfig_int(ibuf, nextensions);
 319         if (err)
 320                 goto done;
 321
 322         TAILQ_FOREACH(node, &tags->fields, link) {
 323                 val = got_gitconfig_get_str(gitconfig, "extensions",
 324                     node->field);
 325                 err = send_gitconfig_pair(ibuf, node->field, val);
 326                 if (err)
 327                         goto done;
 328         }
 329 done:
 330         got_gitconfig_free_list(tags);
 331         return err;
 332 }
 333
 334 int
 335 main(int argc, char *argv[])
 336 {
 337         const struct got_error *err = NULL;
 338         struct imsgbuf ibuf;
 339         size_t datalen;
 340         struct got_gitconfig *gitconfig = NULL;
 341 #if 0
 342         static int attached;
 343
 344         while (!attached)
 345                 sleep(1);
 346 #endif
 347         signal(SIGINT, catch_sigint);
 348
 349         if (imsgbuf_init(&ibuf, GOT_IMSG_FD_CHILD) == -1) {
 350                 warn("imsgbuf_init");
 351                 return 1;
 352         }
 353         imsgbuf_allow_fdpass(&ibuf);
 354
 355 #ifndef PROFILE
 356         /* revoke access to most system calls */
 357         if (pledge("stdio recvfd", NULL) == -1) {
 358                 err = got_error_from_errno("pledge");
 359                 got_privsep_send_error(&ibuf, err);
 360                 imsgbuf_clear(&ibuf);
 361                 return 1;
 362         }
 363
 364         /* revoke fs access */
 365         if (landlock_no_fs() == -1) {
 366                 err = got_error_from_errno("landlock_no_fs");
 367                 got_privsep_send_error(&ibuf, err);
 368                 return 1;
 369         }
 370         if (cap_enter() == -1) {
 371                 err = got_error_from_errno("cap_enter");
 372                 got_privsep_send_error(&ibuf, err);
 373                 return 1;
 374         }
 375 #endif
 376
 377         for (;;) {
 378                 struct imsg imsg;
 379                 int fd = -1;
 380
 381                 memset(&imsg, 0, sizeof(imsg));
 382
 383                 if (sigint_received) {
 384                         err = got_error(GOT_ERR_CANCELLED);
 385                         break;
 386                 }
 387
 388                 err = got_privsep_recv_imsg(&imsg, &ibuf, 0);
 389                 if (err) {
 390                         if (err->code == GOT_ERR_PRIVSEP_PIPE)
 391                                 err = NULL;
 392                         break;
 393                 }
 394
 395                 if (imsg.hdr.type == GOT_IMSG_STOP)
 396                         break;
 397
 398                 switch (imsg.hdr.type) {
 399                 case GOT_IMSG_GITCONFIG_PARSE_REQUEST:
 400                         datalen = imsg.hdr.len - IMSG_HEADER_SIZE;
 401                         if (datalen != 0) {
 402                                 err = got_error(GOT_ERR_PRIVSEP_LEN);
 403                                 break;
 404                         }
 405                         fd = imsg_get_fd(&imsg);
 406                         if (fd == -1) {
 407                                 err = got_error(GOT_ERR_PRIVSEP_NO_FD);
 408                                 break;
 409                         }
 410
 411                         if (gitconfig)
 412                                 got_gitconfig_close(gitconfig);
 413                         err = got_gitconfig_open(&gitconfig, fd);
 414                         break;
 415                 case GOT_IMSG_GITCONFIG_REPOSITORY_FORMAT_VERSION_REQUEST:
 416                         err = gitconfig_num_request(&ibuf, gitconfig, "core",
 417                             "repositoryformatversion", 0);
 418                         break;
 419                 case GOT_IMSG_GITCONFIG_REPOSITORY_EXTENSIONS_REQUEST:
 420                         err = gitconfig_extensions_request(&ibuf, gitconfig);
 421                         break;
 422                 case GOT_IMSG_GITCONFIG_AUTHOR_NAME_REQUEST:
 423                         err = gitconfig_str_request(&ibuf, gitconfig, "user",
 424                             "name");
 425                         break;
 426                 case GOT_IMSG_GITCONFIG_AUTHOR_EMAIL_REQUEST:
 427                         err = gitconfig_str_request(&ibuf, gitconfig, "user",
 428                             "email");
 429                         break;
 430                 case GOT_IMSG_GITCONFIG_REMOTES_REQUEST:
 431                         err = gitconfig_remotes_request(&ibuf, gitconfig);
 432                         break;
 433                 case GOT_IMSG_GITCONFIG_OWNER_REQUEST:
 434                         err = gitconfig_owner_request(&ibuf, gitconfig);
 435                         break;
 436                 default:
 437                         err = got_error(GOT_ERR_PRIVSEP_MSG);
 438                         break;
 439                 }
 440
 441                 if (fd != -1) {
 442                         if (close(fd) == -1 && err == NULL)
 443                                 err = got_error_from_errno("close");
 444                 }
 445
 446                 imsg_free(&imsg);
 447                 if (err)
 448                         break;
 449         }
 450
 451         if (err) {
 452                 if (!sigint_received && err->code != GOT_ERR_PRIVSEP_PIPE) {
 453                         fprintf(stderr, "%s: %s\n", getprogname(), err->msg);
 454                         got_privsep_send_error(&ibuf, err);
 455                 }
 456         }
 457         if (gitconfig)
 458                 got_gitconfig_close(gitconfig);
 459         imsgbuf_clear(&ibuf);
 460         if (close(GOT_IMSG_FD_CHILD) == -1 && err == NULL)
 461                 err = got_error_from_errno("close");
 462         return err ? 1 : 0;
 463 }