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 <stdint.h>
  23 #include <limits.h>
  24 #include <signal.h>
  25 #include <stdio.h>
  26 #include <stdlib.h>
  27 #include <string.h>
  28 #include <unistd.h>
  29 #include <zlib.h>
  30
  31 #include "got_compat.h"
  32
  33 #include "got_error.h"
  34 #include "got_object.h"
  35 #include "got_path.h"
  36
  37 #include "got_lib_delta.h"
  38 #include "got_lib_inflate.h"
  39 #include "got_lib_object.h"
  40 #include "got_lib_object_parse.h"
  41 #include "got_lib_privsep.h"
  42 #include "got_lib_hash.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 int
  53 main(int argc, char *argv[])
  54 {
  55         const struct got_error *err = NULL;
  56         struct imsgbuf ibuf;
  57         size_t datalen;
  58         struct got_parsed_tree_entry *entries = NULL;
  59         size_t nentries = 0, nentries_alloc = 0;
  60
  61         signal(SIGINT, catch_sigint);
  62
  63         imsg_init(&ibuf, GOT_IMSG_FD_CHILD);
  64
  65 #ifndef PROFILE
  66         /* revoke access to most system calls */
  67         if (pledge("stdio recvfd", NULL) == -1) {
  68                 err = got_error_from_errno("pledge");
  69                 got_privsep_send_error(&ibuf, err);
  70                 return 1;
  71         }
  72
  73         /* revoke fs access */
  74         if (landlock_no_fs() == -1) {
  75                 err = got_error_from_errno("landlock_no_fs");
  76                 got_privsep_send_error(&ibuf, err);
  77                 return 1;
  78         }
  79         if (cap_enter() == -1) {
  80                 err = got_error_from_errno("cap_enter");
  81                 got_privsep_send_error(&ibuf, err);
  82                 return 1;
  83         }
  84 #endif
  85
  86         for (;;) {
  87                 struct imsg imsg;
  88                 uint8_t *buf = NULL;
  89                 struct got_object_id expected_id;
  90                 int fd = -1;
  91
  92                 if (sigint_received) {
  93                         err = got_error(GOT_ERR_CANCELLED);
  94                         break;
  95                 }
  96
  97                 err = got_privsep_recv_imsg(&imsg, &ibuf, 0);
  98                 if (err) {
  99                         if (err->code == GOT_ERR_PRIVSEP_PIPE)
 100                                 err = NULL;
 101                         break;
 102                 }
 103
 104                 if (imsg.hdr.type == GOT_IMSG_STOP)
 105                         break;
 106
 107                 if (imsg.hdr.type != GOT_IMSG_TREE_REQUEST) {
 108                         err = got_error(GOT_ERR_PRIVSEP_MSG);
 109                         goto done;
 110                 }
 111
 112                 datalen = imsg.hdr.len - IMSG_HEADER_SIZE;
 113                 if (datalen != sizeof(expected_id)) {
 114                         err = got_error(GOT_ERR_PRIVSEP_LEN);
 115                         goto done;
 116                 }
 117                 memcpy(&expected_id, imsg.data, sizeof(expected_id));
 118
 119                 fd = imsg_get_fd(&imsg);
 120                 if (fd == -1) {
 121                         err = got_error(GOT_ERR_PRIVSEP_NO_FD);
 122                         goto done;
 123                 }
 124
 125                 /* Always assume file offset zero. */
 126                 err = got_object_read_tree(&entries, &nentries, &nentries_alloc,
 127                     &buf, fd, &expected_id);
 128                 if (err)
 129                         goto done;
 130
 131                 err = got_privsep_send_tree(&ibuf, entries, nentries);
 132 done:
 133                 free(buf);
 134                 if (fd != -1 && close(fd) == -1 && err == NULL)
 135                         err = got_error_from_errno("close");
 136                 imsg_free(&imsg);
 137                 if (err)
 138                         break;
 139         }
 140
 141         free(entries);
 142         imsg_clear(&ibuf);
 143         if (err) {
 144                 if (!sigint_received && err->code != GOT_ERR_PRIVSEP_PIPE) {
 145                         fprintf(stderr, "%s: %s\n", getprogname(), err->msg);
 146                         got_privsep_send_error(&ibuf, err);
 147                 }
 148         }
 149         if (close(GOT_IMSG_FD_CHILD) == -1 && err == NULL)
 150                 err = got_error_from_errno("close");
 151         return err ? 1 : 0;
 152 }