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