1 /*
2  * Copyright (c) 2018, 2019, 2020 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/syslimits.h>
22 
23 #include <stdint.h>
24 #include <imsg.h>
25 #include <limits.h>
26 #include <signal.h>
27 #include <stdio.h>
28 #include <stdlib.h>
29 #include <string.h>
30 #include <sha1.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 
43 static volatile sig_atomic_t sigint_received;
44 
45 static void
46 catch_sigint(int signo)
47 {
48 	sigint_received = 1;
49 }
50 
51 static const struct got_error *
52 read_commit_object(struct got_commit_object **commit, FILE *f)
53 {
54 	struct got_object *obj;
55 	const struct got_error *err = NULL;
56 	size_t len;
57 	uint8_t *p;
58 
59 	err = got_inflate_to_mem(&p, &len, NULL, f);
60 	if (err)
61 		return err;
62 
63 	err = got_object_parse_header(&obj, p, len);
64 	if (err) {
65 		free(p);
66 		return err;
67 	}
68 
69 	if (len < obj->hdrlen + obj->size) {
70 		err = got_error(GOT_ERR_BAD_OBJ_DATA);
71 		goto done;
72 	}
73 
74 	if (obj->type != GOT_OBJ_TYPE_COMMIT) {
75 		err = got_error(GOT_ERR_OBJ_TYPE);
76 		goto done;
77 	}
78 
79 	/* Skip object header. */
80 	len -= obj->hdrlen;
81 	err = got_object_parse_commit(commit, p + obj->hdrlen, len);
82 done:
83 	free(p);
84 	got_object_close(obj);
85 	return err;
86 }
87 
88 int
89 main(int argc, char *argv[])
90 {
91 	const struct got_error *err = NULL;
92 	struct imsgbuf ibuf;
93 
94 	signal(SIGINT, catch_sigint);
95 
96 	imsg_init(&ibuf, GOT_IMSG_FD_CHILD);
97 
98 #ifndef PROFILE
99 	/* revoke access to most system calls */
100 	if (pledge("stdio recvfd", NULL) == -1) {
101 		err = got_error_from_errno("pledge");
102 		got_privsep_send_error(&ibuf, err);
103 		return 1;
104 	}
105 #endif
106 
107 	for (;;) {
108 		struct imsg imsg;
109 		FILE *f = NULL;
110 		struct got_commit_object *commit = NULL;
111 
112 		if (sigint_received) {
113 			err = got_error(GOT_ERR_CANCELLED);
114 			break;
115 		}
116 
117 		err = got_privsep_recv_imsg(&imsg, &ibuf, 0);
118 		if (err) {
119 			if (err->code == GOT_ERR_PRIVSEP_PIPE)
120 				err = NULL;
121 			break;
122 		}
123 
124 		if (imsg.hdr.type == GOT_IMSG_STOP)
125 			break;
126 
127 		if (imsg.hdr.type != GOT_IMSG_COMMIT_REQUEST) {
128 			err = got_error(GOT_ERR_PRIVSEP_MSG);
129 			goto done;
130 		}
131 
132 		if (imsg.fd == -1) {
133 			err = got_error(GOT_ERR_PRIVSEP_NO_FD);
134 			goto done;
135 		}
136 
137 		/* Always assume file offset zero. */
138 		f = fdopen(imsg.fd, "rb");
139 		if (f == NULL) {
140 			err = got_error_from_errno("fdopen");
141 			goto done;
142 		}
143 
144 		err = read_commit_object(&commit, f);
145 		if (err)
146 			goto done;
147 
148 		err = got_privsep_send_commit(&ibuf, commit);
149 		got_object_commit_close(commit);
150 done:
151 		if (f) {
152 			if (fclose(f) != 0 && err == NULL)
153 				err = got_error_from_errno("fclose");
154 		} else if (imsg.fd != -1) {
155 			if (close(imsg.fd) != 0 && err == NULL)
156 				err = got_error_from_errno("close");
157 		}
158 		imsg_free(&imsg);
159 		if (err)
160 			break;
161 	}
162 
163 	imsg_clear(&ibuf);
164 	if (err) {
165 		if (!sigint_received && err->code != GOT_ERR_PRIVSEP_PIPE) {
166 			fprintf(stderr, "%s: %s\n", getprogname(), err->msg);
167 			got_privsep_send_error(&ibuf, err);
168 		}
169 	}
170 	if (close(GOT_IMSG_FD_CHILD) != 0 && err == NULL)
171 		err = got_error_from_errno("close");
172 	return err ? 1 : 0;
173 }