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 #include <sys/syslimits.h>
22 
23 #include <stdint.h>
24 #include <imsg.h>
25 #include <limits.h>
26 #include <signal.h>
27 #include <stdio.h>
28 #include <stdlib.h>
29 #include <string.h>
30 #include <sha1.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 
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 read_tree_object(struct got_pathlist_head *entries, int *nentries,
54     uint8_t **p, FILE *f)
55 {
56 	const struct got_error *err = NULL;
57 	struct got_object *obj;
58 	size_t len;
59 
60 	err = got_inflate_to_mem(p, &len, NULL, f);
61 	if (err)
62 		return err;
63 
64 	err = got_object_parse_header(&obj, *p, len);
65 	if (err)
66 		return err;
67 
68 	if (len < obj->hdrlen + obj->size) {
69 		err = got_error(GOT_ERR_BAD_OBJ_DATA);
70 		goto done;
71 	}
72 
73 	/* Skip object header. */
74 	len -= obj->hdrlen;
75 	err = got_object_parse_tree(entries, nentries, *p + obj->hdrlen, len);
76 done:
77 	got_object_close(obj);
78 	return err;
79 }
80 
81 int
82 main(int argc, char *argv[])
83 {
84 	const struct got_error *err = NULL;
85 	struct imsgbuf ibuf;
86 
87 	signal(SIGINT, catch_sigint);
88 
89 	imsg_init(&ibuf, GOT_IMSG_FD_CHILD);
90 
91 #ifndef PROFILE
92 	/* revoke access to most system calls */
93 	if (pledge("stdio recvfd", NULL) == -1) {
94 		err = got_error_from_errno("pledge");
95 		got_privsep_send_error(&ibuf, err);
96 		return 1;
97 	}
98 #endif
99 
100 	for (;;) {
101 		struct imsg imsg;
102 		FILE *f = NULL;
103 		struct got_pathlist_head entries;
104 		int nentries = 0;
105 		uint8_t *buf = NULL;
106 
107 		TAILQ_INIT(&entries);
108 
109 		if (sigint_received) {
110 			err = got_error(GOT_ERR_CANCELLED);
111 			break;
112 		}
113 
114 		err = got_privsep_recv_imsg(&imsg, &ibuf, 0);
115 		if (err) {
116 			if (err->code == GOT_ERR_PRIVSEP_PIPE)
117 				err = NULL;
118 			break;
119 		}
120 
121 		if (imsg.hdr.type == GOT_IMSG_STOP)
122 			break;
123 
124 		if (imsg.hdr.type != GOT_IMSG_TREE_REQUEST) {
125 			err = got_error(GOT_ERR_PRIVSEP_MSG);
126 			goto done;
127 		}
128 
129 		if (imsg.fd == -1) {
130 			err = got_error(GOT_ERR_PRIVSEP_NO_FD);
131 			goto done;
132 		}
133 
134 		/* Always assume file offset zero. */
135 		f = fdopen(imsg.fd, "rb");
136 		if (f == NULL) {
137 			err = got_error_from_errno("fdopen");
138 			goto done;
139 		}
140 
141 		err = read_tree_object(&entries, &nentries, &buf, f);
142 		if (err)
143 			goto done;
144 
145 		err = got_privsep_send_tree(&ibuf, &entries, nentries);
146 done:
147 		got_object_parsed_tree_entries_free(&entries);
148 		free(buf);
149 		if (f) {
150 			if (fclose(f) != 0 && err == NULL)
151 				err = got_error_from_errno("fclose");
152 		} else if (imsg.fd != -1) {
153 			if (close(imsg.fd) != 0 && err == NULL)
154 				err = got_error_from_errno("close");
155 		}
156 		imsg_free(&imsg);
157 		if (err)
158 			break;
159 	}
160 
161 	imsg_clear(&ibuf);
162 	if (err) {
163 		if (!sigint_received && err->code != GOT_ERR_PRIVSEP_PIPE) {
164 			fprintf(stderr, "%s: %s\n", getprogname(), err->msg);
165 			got_privsep_send_error(&ibuf, err);
166 		}
167 	}
168 	if (close(GOT_IMSG_FD_CHILD) != 0 && err == NULL)
169 		err = got_error_from_errno("close");
170 	return err ? 1 : 0;
171 }