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 <imsg.h>
24 #include <limits.h>
25 #include <signal.h>
26 #include <stdio.h>
27 #include <stdlib.h>
28 #include <string.h>
29 #include <sha1.h>
30 #include <sha2.h>
31 #include <unistd.h>
32 #include <zlib.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_inflate.h"
40 #include "got_lib_object.h"
41 #include "got_lib_object_parse.h"
42 #include "got_lib_privsep.h"
43 #include "got_lib_hash.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 	imsg_init(&ibuf, GOT_IMSG_FD_CHILD);
65 
66 #ifndef PROFILE
67 	/* revoke access to most system calls */
68 	if (pledge("stdio recvfd", NULL) == -1) {
69 		err = got_error_from_errno("pledge");
70 		got_privsep_send_error(&ibuf, err);
71 		return 1;
72 	}
73 #endif
74 
75 	for (;;) {
76 		struct imsg imsg;
77 		uint8_t *buf = NULL;
78 		struct got_object_id expected_id;
79 
80 		if (sigint_received) {
81 			err = got_error(GOT_ERR_CANCELLED);
82 			break;
83 		}
84 
85 		err = got_privsep_recv_imsg(&imsg, &ibuf, 0);
86 		if (err) {
87 			if (err->code == GOT_ERR_PRIVSEP_PIPE)
88 				err = NULL;
89 			break;
90 		}
91 
92 		if (imsg.hdr.type == GOT_IMSG_STOP)
93 			break;
94 
95 		if (imsg.hdr.type != GOT_IMSG_TREE_REQUEST) {
96 			err = got_error(GOT_ERR_PRIVSEP_MSG);
97 			goto done;
98 		}
99 
100 		datalen = imsg.hdr.len - IMSG_HEADER_SIZE;
101 		if (datalen != sizeof(expected_id)) {
102 			err = got_error(GOT_ERR_PRIVSEP_LEN);
103 			goto done;
104 		}
105 		memcpy(&expected_id, imsg.data, sizeof(expected_id));
106 
107 		if (imsg.fd == -1) {
108 			err = got_error(GOT_ERR_PRIVSEP_NO_FD);
109 			goto done;
110 		}
111 
112 		/* Always assume file offset zero. */
113 		err = got_object_read_tree(&entries, &nentries, &nentries_alloc,
114 		    &buf, imsg.fd, &expected_id);
115 		if (err)
116 			goto done;
117 
118 		err = got_privsep_send_tree(&ibuf, entries, nentries);
119 done:
120 		free(buf);
121 		if (imsg.fd != -1 && close(imsg.fd) == -1 && err == NULL)
122 			err = got_error_from_errno("close");
123 		imsg_free(&imsg);
124 		if (err)
125 			break;
126 	}
127 
128 	free(entries);
129 	imsg_clear(&ibuf);
130 	if (err) {
131 		if (!sigint_received && err->code != GOT_ERR_PRIVSEP_PIPE) {
132 			fprintf(stderr, "%s: %s\n", getprogname(), err->msg);
133 			got_privsep_send_error(&ibuf, err);
134 		}
135 	}
136 	if (close(GOT_IMSG_FD_CHILD) == -1 && err == NULL)
137 		err = got_error_from_errno("close");
138 	return err ? 1 : 0;
139 }