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 
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 
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 #ifndef nitems
45 #define nitems(_a) (sizeof(_a) / sizeof((_a)[0]))
46 #endif
47 
48 #define GOT_OBJ_TAG_COMMIT	"commit"
49 #define GOT_OBJ_TAG_TREE	"tree"
50 #define GOT_OBJ_TAG_BLOB	"blob"
51 #define GOT_OBJ_TAG_TAG		"tag"
52 
53 static volatile sig_atomic_t sigint_received;
54 
55 static void
56 catch_sigint(int signo)
57 {
58 	sigint_received = 1;
59 }
60 
61 static const struct got_error *
62 send_raw_obj(struct imsgbuf *ibuf, struct got_object *obj,
63     struct got_object_id *expected_id,
64     int fd, int outfd)
65 {
66 	const struct got_error *err = NULL;
67 	uint8_t *data = NULL;
68 	off_t size;
69 	size_t hdrlen;
70 
71 	if (lseek(fd, SEEK_SET, 0) == -1) {
72 		err = got_error_from_errno("lseek");
73 		goto done;
74 	}
75 
76 	err = got_object_read_raw(&data, &size, &hdrlen,
77 	    GOT_PRIVSEP_INLINE_BLOB_DATA_MAX, outfd, expected_id, fd);
78 	if (err)
79 		goto done;
80 
81 	err = got_privsep_send_raw_obj(ibuf, size, hdrlen, data);
82 done:
83 	free(data);
84 	if (close(fd) == -1 && err == NULL)
85 		err = got_error_from_errno("close");
86 	return err;
87 }
88 
89 int
90 main(int argc, char *argv[])
91 {
92 	const struct got_error *err = NULL;
93 	struct got_object *obj = NULL;
94 	struct imsg imsg;
95 	struct imsgbuf ibuf;
96 	size_t datalen;
97 	struct got_object_id expected_id;
98 
99 	signal(SIGINT, catch_sigint);
100 
101 	imsg_init(&ibuf, GOT_IMSG_FD_CHILD);
102 
103 #ifndef PROFILE
104 	/* revoke access to most system calls */
105 	if (pledge("stdio recvfd", NULL) == -1) {
106 		err = got_error_from_errno("pledge");
107 		got_privsep_send_error(&ibuf, err);
108 		return 1;
109 	}
110 #endif
111 
112 	for (;;) {
113 		int fd = -1, outfd = -1;
114 
115 		if (sigint_received) {
116 			err = got_error(GOT_ERR_CANCELLED);
117 			break;
118 		}
119 
120 		err = got_privsep_recv_imsg(&imsg, &ibuf, 0);
121 		if (err) {
122 			if (err->code == GOT_ERR_PRIVSEP_PIPE)
123 				err = NULL;
124 			break;
125 		}
126 
127 		if (imsg.hdr.type == GOT_IMSG_STOP)
128 			break;
129 
130 		if (imsg.hdr.type != GOT_IMSG_OBJECT_REQUEST &&
131 		    imsg.hdr.type != GOT_IMSG_RAW_OBJECT_REQUEST) {
132 			err = got_error(GOT_ERR_PRIVSEP_MSG);
133 			goto done;
134 		}
135 
136 		datalen = imsg.hdr.len - IMSG_HEADER_SIZE;
137 		if (datalen != sizeof(expected_id)) {
138 			err = got_error(GOT_ERR_PRIVSEP_LEN);
139 			goto done;
140 		}
141 		memcpy(&expected_id, imsg.data, sizeof(expected_id));
142 
143 		fd = imsg_get_fd(&imsg);
144 		if (fd == -1) {
145 			err = got_error(GOT_ERR_PRIVSEP_NO_FD);
146 			goto done;
147 		}
148 
149 		err = got_object_read_header(&obj, fd);
150 		if (err)
151 			goto done;
152 
153 		if (imsg.hdr.type == GOT_IMSG_RAW_OBJECT_REQUEST) {
154 			struct imsg imsg_outfd;
155 
156 			err = got_privsep_recv_imsg(&imsg_outfd, &ibuf, 0);
157 			if (err) {
158 				if (imsg_outfd.hdr.len == 0)
159 					err = NULL;
160 				goto done;
161 			}
162 
163 			if (imsg_outfd.hdr.type == GOT_IMSG_STOP) {
164 				imsg_free(&imsg_outfd);
165 				goto done;
166 			}
167 
168 			if (imsg_outfd.hdr.type != GOT_IMSG_RAW_OBJECT_OUTFD) {
169 				err = got_error(GOT_ERR_PRIVSEP_MSG);
170 				imsg_free(&imsg_outfd);
171 				goto done;
172 			}
173 
174 			datalen = imsg_outfd.hdr.len - IMSG_HEADER_SIZE;
175 			if (datalen != 0) {
176 				err = got_error(GOT_ERR_PRIVSEP_LEN);
177 				imsg_free(&imsg_outfd);
178 				goto done;
179 			}
180 			outfd = imsg_get_fd(&imsg_outfd);
181 			if (outfd == -1) {
182 				err = got_error(GOT_ERR_PRIVSEP_NO_FD);
183 				imsg_free(&imsg_outfd);
184 				goto done;
185 			}
186 			err = send_raw_obj(&ibuf, obj, &expected_id,
187 			    fd, outfd);
188 			fd = -1; /* fd is owned by send_raw_obj() */
189 			if (close(outfd) == -1 && err == NULL)
190 				err = got_error_from_errno("close");
191 			imsg_free(&imsg_outfd);
192 			if (err)
193 				goto done;
194 		} else
195 			err = got_privsep_send_obj(&ibuf, obj);
196 done:
197 		if (fd != -1 && close(fd) == -1 && err == NULL)
198 			err = got_error_from_errno("close");
199 		imsg_free(&imsg);
200 		if (obj)
201 			got_object_close(obj);
202 		if (err)
203 			break;
204 	}
205 
206 	imsg_clear(&ibuf);
207 	if (err) {
208 		if(!sigint_received && err->code != GOT_ERR_PRIVSEP_PIPE) {
209 			fprintf(stderr, "%s: %s\n", getprogname(), err->msg);
210 			got_privsep_send_error(&ibuf, err);
211 		}
212 	}
213 	if (close(GOT_IMSG_FD_CHILD) == -1 && err == NULL)
214 		err = got_error_from_errno("close");
215 	return err ? 1 : 0;
216 }