aboutsummaryrefslogtreecommitdiffstats
path: root/hostapd/common.c
blob: 0679dee0c49ab1fc68d84b099aa6cba63586aac8 (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
/*
 * Host AP (software wireless LAN access point) user space daemon for
 * Host AP kernel driver / common helper functions, etc.
 * Copyright (c) 2002-2004, Jouni Malinen <jkmaline@cc.hut.fi>
 *
 * This program is free software; you can redistribute it and/or modify
 * it under the terms of the GNU General Public License version 2 as
 * published by the Free Software Foundation.
 *
 * Alternatively, this software may be distributed under the terms of BSD
 * license.
 *
 * See README and COPYING for more details.
 */

#include <stdlib.h>
#include <stdio.h>
#include <string.h>
#include <unistd.h>
#include <errno.h>

#include "common.h"


int hostapd_get_rand(u8 *buf, size_t len)
{
	FILE *f;
	size_t rc;

	f = fopen("/dev/urandom", "r");
	if (f == NULL) {
		printf("Could not open /dev/urandom.\n");
		return -1;
	}

	rc = fread(buf, 1, len, f);
	fclose(f);

	return rc != len ? -1 : 0;
}


void hostapd_hexdump(const char *title, u8 *buf, size_t len)
{
	size_t i;
	printf("%s - hexdump(len=%d):", title, len);
	for (i = 0; i < len; i++)
		printf(" %02x", buf[i]);
	printf("\n");
}


static int hex2num(char c)
{
	if (c >= '0' && c <= '9')
		return c - '0';
	if (c >= 'a' && c <= 'f')
		return c - 'a' + 10;
	if (c >= 'A' && c <= 'F')
		return c - 'A' + 10;
	return -1;
}


static int hex2byte(const char *hex)
{
	int a, b;
	a = hex2num(*hex++);
	if (a < 0)
		return -1;
	b = hex2num(*hex++);
	if (b < 0)
		return -1;
	return (a << 4) | b;
}


int hwaddr_aton(const char *txt, u8 *addr)
{
	int i;

	for (i = 0; i < 6; i++) {
		int a, b;

		a = hex2num(*txt++);
		if (a < 0)
			return -1;
		b = hex2num(*txt++);
		if (b < 0)
			return -1;
		*addr++ = (a << 4) | b;
		if (i < 5 && *txt++ != ':')
			return -1;
	}

	return 0;
}


int hexstr2bin(const char *hex, u8 *buf, size_t len)
{
	int i, a;
	const char *ipos = hex;
	char *opos = buf;

	for (i = 0; i < len; i++) {
		a = hex2byte(ipos);
		if (a < 0)
			return -1;
		*opos++ = a;
		ipos += 2;
	}
	return 0;
}


char * rel2abs_path(const char *rel_path)
{
	char *buf = NULL, *cwd, *ret;
	size_t len = 128, cwd_len, rel_len, ret_len;

	if (rel_path[0] == '/')
		return strdup(rel_path);

	for (;;) {
		buf = malloc(len);
		if (buf == NULL)
			return NULL;
		cwd = getcwd(buf, len);
		if (cwd == NULL) {
			free(buf);
			if (errno != ERANGE) {
				return NULL;
			}
			len *= 2;
		} else {
			break;
		}
	}

	cwd_len = strlen(cwd);
	rel_len = strlen(rel_path);
	ret_len = cwd_len + 1 + rel_len + 1;
	ret = malloc(ret_len);
	if (ret) {
		memcpy(ret, cwd, cwd_len);
		ret[cwd_len] = '/';
		memcpy(ret + cwd_len + 1, rel_path, rel_len);
		ret[ret_len - 1] = '\0';
	}
	free(buf);
	return ret;
}


void inc_byte_array(u8 *counter, size_t len)
{
	int pos = len - 1;
	while (pos >= 0) {
		counter[pos]++;
		if (counter[pos] != 0)
			break;
		pos--;
	}
}