1 /*
2  * Copyright (c) 2018 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/limits.h>
22 #include <sys/syslimits.h>
23 
24 #include <stdint.h>
25 #include <imsg.h>
26 #include <signal.h>
27 #include <stdio.h>
28 #include <stdlib.h>
29 #include <string.h>
30 #include <sha1.h>
31 #include <zlib.h>
32 
33 #include "got_error.h"
34 #include "got_object.h"
35 
36 #include "got_lib_delta.h"
37 #include "got_lib_inflate.h"
38 #include "got_lib_object.h"
39 #include "got_lib_object_parse.h"
40 #include "got_lib_privsep.h"
41 
42 static volatile sig_atomic_t sigint_received;
43 
44 static void
45 catch_sigint(int signo)
46 {
47 	sigint_received = 1;
48 }
49 static const struct got_error *
50 read_tree_object(struct got_tree_object **tree, struct got_object *obj, FILE *f)
51 {
52 	const struct got_error *err = NULL;
53 	size_t len;
54 	uint8_t *p;
55 
56 	if (obj->flags & GOT_OBJ_FLAG_PACKED)
57 		err = got_read_file_to_mem(&p, &len, f);
58 	else
59 		err = got_inflate_to_mem(&p, &len, f);
60 	if (err)
61 		return err;
62 
63 	if (len < obj->hdrlen + obj->size) {
64 		err = got_error(GOT_ERR_BAD_OBJ_DATA);
65 		goto done;
66 	}
67 
68 	/* Skip object header. */
69 	len -= obj->hdrlen;
70 	err = got_object_parse_tree(tree, p + obj->hdrlen, len);
71 	free(p);
72 done:
73 	return err;
74 }
75 
76 int
77 main(int argc, char *argv[])
78 {
79 	const struct got_error *err = NULL;
80 	struct got_tree_object *tree = NULL;
81 	struct imsgbuf ibuf;
82 	size_t datalen;
83 
84 	signal(SIGINT, catch_sigint);
85 
86 	imsg_init(&ibuf, GOT_IMSG_FD_CHILD);
87 
88 #ifndef PROFILE
89 	/* revoke access to most system calls */
90 	if (pledge("stdio recvfd", NULL) == -1) {
91 		err = got_error_from_errno();
92 		got_privsep_send_error(&ibuf, err);
93 		return 1;
94 	}
95 #endif
96 
97 	while (1) {
98 		struct imsg imsg;
99 		struct got_imsg_object iobj;
100 		FILE *f = NULL;
101 		struct got_object *obj = NULL;
102 
103 		if (sigint_received) {
104 			err = got_error(GOT_ERR_CANCELLED);
105 			break;
106 		}
107 	
108 		err = got_privsep_recv_imsg(&imsg, &ibuf, 0);
109 		if (err) {
110 			if (err->code == GOT_ERR_PRIVSEP_PIPE)
111 				err = NULL;
112 			break;
113 		}
114 
115 		if (imsg.hdr.type == GOT_IMSG_STOP)
116 			break;
117 
118 		if (imsg.hdr.type != GOT_IMSG_TREE_REQUEST) {
119 			err = got_error(GOT_ERR_PRIVSEP_MSG);
120 			goto done;
121 		}
122 
123 		datalen = imsg.hdr.len - IMSG_HEADER_SIZE;
124 		if (datalen != sizeof(iobj)) {
125 			err = got_error(GOT_ERR_PRIVSEP_LEN);
126 			goto done;
127 		}
128 
129 		memcpy(&iobj, imsg.data, sizeof(iobj));
130 		if (iobj.type != GOT_OBJ_TYPE_TREE) {
131 			err = got_error(GOT_ERR_OBJ_TYPE);
132 			goto done;
133 		}
134 
135 		if (imsg.fd == -1) {
136 			err = got_error(GOT_ERR_PRIVSEP_NO_FD);
137 			goto done;
138 		}
139 
140 		obj = calloc(1, sizeof(*obj));
141 		if (obj == NULL) {
142 			err = got_error_from_errno();
143 			goto done;
144 		}
145 		obj->type = iobj.type;
146 		obj->hdrlen = iobj.hdrlen;
147 		obj->size = iobj.size;
148 
149 		/* Always assume file offset zero. */
150 		f = fdopen(imsg.fd, "rb");
151 		if (f == NULL) {
152 			err = got_error_from_errno();
153 			goto done;
154 		}
155 
156 		err = read_tree_object(&tree, obj, f);
157 		if (err)
158 			goto done;
159 
160 		err = got_privsep_send_tree(&ibuf, tree);
161 done:
162 		if (f)
163 			fclose(f);
164 		else if (imsg.fd != -1)
165 			close(imsg.fd);
166 		imsg_free(&imsg);
167 		if (obj)
168 			got_object_close(obj);
169 		if (err)
170 			break;
171 	}
172 
173 	imsg_clear(&ibuf);
174 	if (err) {
175 		if (!sigint_received && err->code != GOT_ERR_PRIVSEP_PIPE) {
176 			fprintf(stderr, "%s: %s\n", getprogname(), err->msg);
177 			got_privsep_send_error(&ibuf, err);
178 		}
179 	}
180 	close(GOT_IMSG_FD_CHILD);
181 	return err ? 1 : 0;
182 }