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 
50 static const struct got_error *
51 read_commit_object(struct got_commit_object **commit, struct got_object *obj,
52     FILE *f)
53 {
54 	const struct got_error *err = NULL;
55 	size_t len;
56 	uint8_t *p;
57 
58 	if (obj->flags & GOT_OBJ_FLAG_PACKED)
59 		err = got_read_file_to_mem(&p, &len, f);
60 	else
61 		err = got_inflate_to_mem(&p, &len, f);
62 	if (err)
63 		return err;
64 
65 	if (len < obj->hdrlen + obj->size) {
66 		err = got_error(GOT_ERR_BAD_OBJ_DATA);
67 		goto done;
68 	}
69 
70 	/* Skip object header. */
71 	len -= obj->hdrlen;
72 	err = got_object_parse_commit(commit, p + obj->hdrlen, len);
73 	free(p);
74 done:
75 	return err;
76 }
77 
78 int
79 main(int argc, char *argv[])
80 {
81 	const struct got_error *err = NULL;
82 	struct got_commit_object *commit = NULL;
83 	struct imsgbuf ibuf;
84 	size_t datalen;
85 
86 	signal(SIGINT, catch_sigint);
87 
88 	imsg_init(&ibuf, GOT_IMSG_FD_CHILD);
89 
90 #ifndef PROFILE
91 	/* revoke access to most system calls */
92 	if (pledge("stdio recvfd", NULL) == -1) {
93 		err = got_error_from_errno();
94 		got_privsep_send_error(&ibuf, err);
95 		return 1;
96 	}
97 #endif
98 
99 	while (1) {
100 		struct imsg imsg;
101 		struct got_imsg_object iobj;
102 		FILE *f = NULL;
103 		struct got_object *obj = NULL;
104 
105 		if (sigint_received) {
106 			err = got_error(GOT_ERR_CANCELLED);
107 			break;
108 		}
109 	
110 		err = got_privsep_recv_imsg(&imsg, &ibuf, 0);
111 		if (err) {
112 			if (err->code == GOT_ERR_PRIVSEP_PIPE)
113 				err = NULL;
114 			break;
115 		}
116 
117 		if (imsg.hdr.type == GOT_IMSG_STOP)
118 			break;
119 
120 		if (imsg.hdr.type != GOT_IMSG_COMMIT_REQUEST) {
121 			err = got_error(GOT_ERR_PRIVSEP_MSG);
122 			goto done;
123 		}
124 
125 		datalen = imsg.hdr.len - IMSG_HEADER_SIZE;
126 		if (datalen != sizeof(iobj)) {
127 			err = got_error(GOT_ERR_PRIVSEP_LEN);
128 			goto done;
129 		}
130 
131 		memcpy(&iobj, imsg.data, sizeof(iobj));
132 		if (iobj.type != GOT_OBJ_TYPE_COMMIT) {
133 			err = got_error(GOT_ERR_OBJ_TYPE);
134 			goto done;
135 		}
136 
137 		if (imsg.fd == -1) {
138 			err = got_error(GOT_ERR_PRIVSEP_NO_FD);
139 			goto done;
140 		}
141 
142 		obj = calloc(1, sizeof(*obj));
143 		if (obj == NULL) {
144 			err = got_error_from_errno();
145 			goto done;
146 		}
147 		obj->type = iobj.type;
148 		obj->hdrlen = iobj.hdrlen;
149 		obj->size = iobj.size;
150 
151 		/* Always assume file offset zero. */
152 		f = fdopen(imsg.fd, "rb");
153 		if (f == NULL) {
154 			err = got_error_from_errno();
155 			goto done;
156 		}
157 
158 		err = read_commit_object(&commit, obj, f);
159 		if (err)
160 			goto done;
161 
162 		err = got_privsep_send_commit(&ibuf, commit);
163 done:
164 		if (f)
165 			fclose(f);
166 		else if (imsg.fd != -1)
167 			close(imsg.fd);
168 		imsg_free(&imsg);
169 		if (obj)
170 			got_object_close(obj);
171 		if (err)
172 			break;
173 	}
174 
175 	imsg_clear(&ibuf);
176 	if (err) {
177 		if (!sigint_received && err->code != GOT_ERR_PRIVSEP_PIPE) {
178 			fprintf(stderr, "%s: %s\n", getprogname(), err->msg);
179 			got_privsep_send_error(&ibuf, err);
180 		}
181 	}
182 	close(GOT_IMSG_FD_CHILD);
183 	return err ? 1 : 0;
184 }