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 		if (sigint_received) {
114 			err = got_error(GOT_ERR_CANCELLED);
115 			break;
116 		}
117 
118 		err = got_privsep_recv_imsg(&imsg, &ibuf, 0);
119 		if (err) {
120 			if (err->code == GOT_ERR_PRIVSEP_PIPE)
121 				err = NULL;
122 			break;
123 		}
124 
125 		if (imsg.hdr.type == GOT_IMSG_STOP)
126 			break;
127 
128 		if (imsg.hdr.type != GOT_IMSG_OBJECT_REQUEST &&
129 		    imsg.hdr.type != GOT_IMSG_RAW_OBJECT_REQUEST) {
130 			err = got_error(GOT_ERR_PRIVSEP_MSG);
131 			goto done;
132 		}
133 
134 		datalen = imsg.hdr.len - IMSG_HEADER_SIZE;
135 		if (datalen != sizeof(expected_id)) {
136 			err = got_error(GOT_ERR_PRIVSEP_LEN);
137 			goto done;
138 		}
139 		memcpy(&expected_id, imsg.data, sizeof(expected_id));
140 
141 		if (imsg.fd == -1) {
142 			err = got_error(GOT_ERR_PRIVSEP_NO_FD);
143 			goto done;
144 		}
145 
146 		err = got_object_read_header(&obj, imsg.fd);
147 		if (err)
148 			goto done;
149 
150 		if (imsg.hdr.type == GOT_IMSG_RAW_OBJECT_REQUEST) {
151 			struct imsg imsg_outfd;
152 
153 			err = got_privsep_recv_imsg(&imsg_outfd, &ibuf, 0);
154 			if (err) {
155 				if (imsg_outfd.hdr.len == 0)
156 					err = NULL;
157 				goto done;
158 			}
159 
160 			if (imsg_outfd.hdr.type == GOT_IMSG_STOP) {
161 				imsg_free(&imsg_outfd);
162 				goto done;
163 			}
164 
165 			if (imsg_outfd.hdr.type != GOT_IMSG_RAW_OBJECT_OUTFD) {
166 				err = got_error(GOT_ERR_PRIVSEP_MSG);
167 				imsg_free(&imsg_outfd);
168 				goto done;
169 			}
170 
171 			datalen = imsg_outfd.hdr.len - IMSG_HEADER_SIZE;
172 			if (datalen != 0) {
173 				err = got_error(GOT_ERR_PRIVSEP_LEN);
174 				imsg_free(&imsg_outfd);
175 				goto done;
176 			}
177 			if (imsg_outfd.fd == -1) {
178 				err = got_error(GOT_ERR_PRIVSEP_NO_FD);
179 				imsg_free(&imsg_outfd);
180 				goto done;
181 			}
182 			err = send_raw_obj(&ibuf, obj, &expected_id,
183 			    imsg.fd, imsg_outfd.fd);
184 			imsg.fd = -1; /* imsg.fd is owned by send_raw_obj() */
185 			if (close(imsg_outfd.fd) == -1 && err == NULL)
186 				err = got_error_from_errno("close");
187 			imsg_free(&imsg_outfd);
188 			if (err)
189 				goto done;
190 		} else
191 			err = got_privsep_send_obj(&ibuf, obj);
192 done:
193 		if (imsg.fd != -1 && close(imsg.fd) == -1 && err == NULL)
194 			err = got_error_from_errno("close");
195 		imsg_free(&imsg);
196 		if (obj)
197 			got_object_close(obj);
198 		if (err)
199 			break;
200 	}
201 
202 	imsg_clear(&ibuf);
203 	if (err) {
204 		if(!sigint_received && err->code != GOT_ERR_PRIVSEP_PIPE) {
205 			fprintf(stderr, "%s: %s\n", getprogname(), err->msg);
206 			got_privsep_send_error(&ibuf, err);
207 		}
208 	}
209 	if (close(GOT_IMSG_FD_CHILD) == -1 && err == NULL)
210 		err = got_error_from_errno("close");
211 	return err ? 1 : 0;
212 }