libexec/got-read-tree/got-read-tree.c

   1 /*
   2  * Copyright (c) 2018, 2019, 2020 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_path.h"
  37
  38 #include "got_lib_delta.h"
  39 #include "got_lib_hash.h"
  40 #include "got_lib_inflate.h"
  41 #include "got_lib_object.h"
  42 #include "got_lib_object_parse.h"
  43 #include "got_lib_privsep.h"
  44
  45 static volatile sig_atomic_t sigint_received;
  46
  47 static void
  48 catch_sigint(int signo)
  49 {
  50         sigint_received = 1;
  51 }
  52
  53 int
  54 main(int argc, char *argv[])
  55 {
  56         const struct got_error *err = NULL;
  57         struct imsgbuf ibuf;
  58         size_t datalen;
  59         struct got_parsed_tree_entry *entries = NULL;
  60         size_t nentries = 0, nentries_alloc = 0;
  61
  62         signal(SIGINT, catch_sigint);
  63
  64         if (imsgbuf_init(&ibuf, GOT_IMSG_FD_CHILD) == -1) {
  65                 warn("imsgbuf_init");
  66                 return 1;
  67         }
  68         imsgbuf_allow_fdpass(&ibuf);
  69
  70 #ifndef PROFILE
  71         /* revoke access to most system calls */
  72         if (pledge("stdio recvfd", NULL) == -1) {
  73                 err = got_error_from_errno("pledge");
  74                 got_privsep_send_error(&ibuf, err);
  75                 return 1;
  76         }
  77
  78         /* revoke fs access */
  79         if (landlock_no_fs() == -1) {
  80                 err = got_error_from_errno("landlock_no_fs");
  81                 got_privsep_send_error(&ibuf, err);
  82                 return 1;
  83         }
  84         if (cap_enter() == -1) {
  85                 err = got_error_from_errno("cap_enter");
  86                 got_privsep_send_error(&ibuf, err);
  87                 return 1;
  88         }
  89 #endif
  90
  91         for (;;) {
  92                 struct imsg imsg;
  93                 uint8_t *buf = NULL;
  94                 struct got_object_id expected_id;
  95                 int fd = -1;
  96
  97                 if (sigint_received) {
  98                         err = got_error(GOT_ERR_CANCELLED);
  99                         break;
 100                 }
 101
 102                 err = got_privsep_recv_imsg(&imsg, &ibuf, 0);
 103                 if (err) {
 104                         if (err->code == GOT_ERR_PRIVSEP_PIPE)
 105                                 err = NULL;
 106                         break;
 107                 }
 108
 109                 if (imsg.hdr.type == GOT_IMSG_STOP)
 110                         break;
 111
 112                 if (imsg.hdr.type != GOT_IMSG_TREE_REQUEST) {
 113                         err = got_error(GOT_ERR_PRIVSEP_MSG);
 114                         goto done;
 115                 }
 116
 117                 datalen = imsg.hdr.len - IMSG_HEADER_SIZE;
 118                 if (datalen != sizeof(expected_id)) {
 119                         err = got_error(GOT_ERR_PRIVSEP_LEN);
 120                         goto done;
 121                 }
 122                 memcpy(&expected_id, imsg.data, sizeof(expected_id));
 123
 124                 fd = imsg_get_fd(&imsg);
 125                 if (fd == -1) {
 126                         err = got_error(GOT_ERR_PRIVSEP_NO_FD);
 127                         goto done;
 128                 }
 129
 130                 /* Always assume file offset zero. */
 131                 err = got_object_read_tree(&entries, &nentries, &nentries_alloc,
 132                     &buf, fd, &expected_id);
 133                 if (err)
 134                         goto done;
 135
 136                 err = got_privsep_send_tree(&ibuf, entries, nentries);
 137 done:
 138                 free(buf);
 139                 if (fd != -1 && close(fd) == -1 && err == NULL)
 140                         err = got_error_from_errno("close");
 141                 imsg_free(&imsg);
 142                 if (err)
 143                         break;
 144         }
 145
 146         free(entries);
 147         if (err) {
 148                 if (!sigint_received && err->code != GOT_ERR_PRIVSEP_PIPE) {
 149                         fprintf(stderr, "%s: %s\n", getprogname(), err->msg);
 150                         got_privsep_send_error(&ibuf, err);
 151                 }
 152         }
 153         imsgbuf_clear(&ibuf);
 154         if (close(GOT_IMSG_FD_CHILD) == -1 && err == NULL)
 155                 err = got_error_from_errno("close");
 156         return err ? 1 : 0;
 157 }