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