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 <sha1.h>
19 #include <errno.h>
20 #include <stdio.h>
21 #include <stdlib.h>
22 #include <limits.h>
23 
24 #include "got_lib_sha1.h"
25 
26 int
27 got_parse_xdigit(uint8_t *val, const char *hex)
28 {
29 	char *ep;
30 	long lval;
31 
32 	errno = 0;
33 	lval = strtol(hex, &ep, 16);
34 	if (hex[0] == '\0' || *ep != '\0')
35 		return 0;
36 	if (errno == ERANGE && (lval == LONG_MAX || lval == LONG_MIN))
37 		return 0;
38 
39 	*val = (uint8_t)lval;
40 	return 1;
41 }
42 
43 int
44 got_parse_sha1_digest(uint8_t *digest, const char *line)
45 {
46 	uint8_t b = 0;
47 	char hex[3] = {'\0', '\0', '\0'};
48 	int i, j;
49 
50 	for (i = 0; i < SHA1_DIGEST_LENGTH; i++) {
51 		if (line[0] == '\0' || line[1] == '\0')
52 			return 0;
53 		for (j = 0; j < 2; j++) {
54 			hex[j] = *line;
55 			line++;
56 		}
57 		if (!got_parse_xdigit(&b, hex))
58 			return 0;
59 		digest[i] = b;
60 	}
61 
62 	return 1;
63 }
64 
65 char *
66 got_sha1_digest_to_str(const uint8_t *digest, char *buf, size_t size)
67 {
68 	char *p = buf;
69 	char hex[3];
70 	int i;
71 
72 	if (size < SHA1_DIGEST_STRING_LENGTH)
73 		return NULL;
74 
75 	for (i = 0; i < SHA1_DIGEST_LENGTH; i++) {
76 		snprintf(hex, sizeof(hex), "%.2x", digest[i]);
77 		p[0] = hex[0];
78 		p[1] = hex[1];
79 		p += 2;
80 	}
81 	p[0] = '\0';
82 
83 	return buf;
84 }