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 <unistd.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 #ifndef nitems
43 #define nitems(_a) (sizeof(_a) / sizeof((_a)[0]))
44 #endif
45 
46 #define GOT_OBJ_TAG_COMMIT	"commit"
47 #define GOT_OBJ_TAG_TREE	"tree"
48 #define GOT_OBJ_TAG_BLOB	"blob"
49 #define GOT_OBJ_TAG_TAG		"tag"
50 
51 static volatile sig_atomic_t sigint_received;
52 
53 static void
54 catch_sigint(int signo)
55 {
56 	sigint_received = 1;
57 }
58 
59 static const struct got_error *
60 send_raw_obj(struct imsgbuf *ibuf, struct got_object *obj, int fd, int outfd)
61 {
62 	const struct got_error *err = NULL;
63 	uint8_t *data = NULL;
64 	size_t len = 0, consumed;
65 	FILE *f;
66 
67 	if (lseek(fd, SEEK_SET, 0) == -1) {
68 		err = got_error_from_errno("lseek");
69 		close(fd);
70 		return err;
71 	}
72 
73 	f = fdopen(fd, "r");
74 	if (f == NULL) {
75 		err = got_error_from_errno("fdopen");
76 		close(fd);
77 		return err;
78 	}
79 
80 	if (obj->size <= GOT_PRIVSEP_INLINE_OBJECT_DATA_MAX)
81 		err = got_inflate_to_mem(&data, &len, &consumed, f);
82 	else
83 		err = got_inflate_to_fd(&len, f, outfd);
84 	if (err)
85 		goto done;
86 
87 	if (len < obj->hdrlen || len != obj->hdrlen + obj->size) {
88 		fprintf(stderr, "len=%zd obj->hdrlen=%zd obj->size=%zd\n", len, obj->hdrlen, obj->size);
89 		err = got_error(GOT_ERR_BAD_OBJ_HDR);
90 		goto done;
91 	}
92 
93 	err = got_privsep_send_raw_obj(ibuf, len, obj->hdrlen, data);
94 done:
95 	free(data);
96 	if (fclose(f) == EOF && err == NULL)
97 		err = got_error_from_errno("fclose");
98 
99 	return err;
100 }
101 
102 int
103 main(int argc, char *argv[])
104 {
105 	const struct got_error *err = NULL;
106 	struct got_object *obj = NULL;
107 	struct imsg imsg;
108 	struct imsgbuf ibuf;
109 	size_t datalen;
110 
111 	signal(SIGINT, catch_sigint);
112 
113 	imsg_init(&ibuf, GOT_IMSG_FD_CHILD);
114 
115 #ifndef PROFILE
116 	/* revoke access to most system calls */
117 	if (pledge("stdio recvfd", NULL) == -1) {
118 		err = got_error_from_errno("pledge");
119 		got_privsep_send_error(&ibuf, err);
120 		return 1;
121 	}
122 #endif
123 
124 	for (;;) {
125 		if (sigint_received) {
126 			err = got_error(GOT_ERR_CANCELLED);
127 			break;
128 		}
129 
130 		err = got_privsep_recv_imsg(&imsg, &ibuf, 0);
131 		if (err) {
132 			if (err->code == GOT_ERR_PRIVSEP_PIPE)
133 				err = NULL;
134 			break;
135 		}
136 
137 		if (imsg.hdr.type == GOT_IMSG_STOP)
138 			break;
139 
140 		if (imsg.hdr.type != GOT_IMSG_OBJECT_REQUEST &&
141 		    imsg.hdr.type != GOT_IMSG_RAW_OBJECT_REQUEST) {
142 			err = got_error(GOT_ERR_PRIVSEP_MSG);
143 			goto done;
144 		}
145 
146 		datalen = imsg.hdr.len - IMSG_HEADER_SIZE;
147 		if (datalen != 0) {
148 			err = got_error(GOT_ERR_PRIVSEP_LEN);
149 			goto done;
150 		}
151 
152 		if (imsg.fd == -1) {
153 			err = got_error(GOT_ERR_PRIVSEP_NO_FD);
154 			goto done;
155 		}
156 
157 		err = got_object_read_header(&obj, imsg.fd);
158 		if (err)
159 			goto done;
160 
161 		if (imsg.hdr.type == GOT_IMSG_RAW_OBJECT_REQUEST) {
162 			struct imsg imsg_outfd;
163 			err = got_privsep_recv_imsg(&imsg_outfd, &ibuf, 0);
164 			if (err) {
165 				if (imsg_outfd.hdr.len == 0)
166 					err = NULL;
167 				goto done;
168 			}
169 
170 			if (imsg_outfd.hdr.type == GOT_IMSG_STOP) {
171 				imsg_free(&imsg_outfd);
172 				goto done;
173 			}
174 
175 			if (imsg_outfd.hdr.type != GOT_IMSG_RAW_OBJECT_OUTFD) {
176 				err = got_error(GOT_ERR_PRIVSEP_MSG);
177 				imsg_free(&imsg_outfd);
178 				goto done;
179 			}
180 
181 			datalen = imsg_outfd.hdr.len - IMSG_HEADER_SIZE;
182 			if (datalen != 0) {
183 				err = got_error(GOT_ERR_PRIVSEP_LEN);
184 				imsg_free(&imsg_outfd);
185 				goto done;
186 			}
187 			if (imsg_outfd.fd == -1) {
188 				err = got_error(GOT_ERR_PRIVSEP_NO_FD);
189 				imsg_free(&imsg_outfd);
190 				goto done;
191 			}
192 			err = send_raw_obj(&ibuf, obj, imsg.fd, imsg_outfd.fd);
193 			imsg.fd = -1; /* imsg.fd is owned by send_raw_obj() */
194 			imsg_free(&imsg_outfd);
195 			if (err)
196 				goto done;
197 		} else
198 			err = got_privsep_send_obj(&ibuf, obj);
199 done:
200 		if (imsg.fd != -1 && close(imsg.fd) == -1 && err == NULL)
201 			err = got_error_from_errno("close");
202 		imsg_free(&imsg);
203 		if (obj)
204 			got_object_close(obj);
205 		if (err)
206 			break;
207 	}
208 
209 	imsg_clear(&ibuf);
210 	if (err) {
211 		if(!sigint_received && err->code != GOT_ERR_PRIVSEP_PIPE) {
212 			fprintf(stderr, "%s: %s\n", getprogname(), err->msg);
213 			got_privsep_send_error(&ibuf, err);
214 		}
215 	}
216 	if (close(GOT_IMSG_FD_CHILD) == -1 && err == NULL)
217 		err = got_error_from_errno("close");
218 	return err ? 1 : 0;
219 }