blob: 6c983a795d28ebcedd40e52ef9ed76db0729d10b [file] [log] [blame]
Paul Bakker367dae42009-06-28 21:50:27 +00001int unhexify(unsigned char *obuf, const char *ibuf)
2{
3 unsigned char c, c2;
4 int len = strlen(ibuf) / 2;
5 assert(!(strlen(ibuf) %1)); // must be even number of bytes
6
7 while (*ibuf != 0)
8 {
9 c = *ibuf++;
10 if( c >= '0' && c <= '9' )
11 c -= '0';
12 else if( c >= 'a' && c <= 'f' )
13 c -= 'a' - 10;
14 else if( c >= 'A' && c <= 'F' )
15 c -= 'A' - 10;
16 else
17 assert( 0 );
18
19 c2 = *ibuf++;
20 if( c2 >= '0' && c2 <= '9' )
21 c2 -= '0';
22 else if( c2 >= 'a' && c2 <= 'f' )
23 c2 -= 'a' - 10;
24 else if( c2 >= 'A' && c2 <= 'F' )
25 c2 -= 'A' - 10;
26 else
27 assert( 0 );
28
29 *obuf++ = ( c << 4 ) | c2;
30 }
31
32 return len;
33}
34
35void hexify(unsigned char *obuf, const unsigned char *ibuf, int len)
36{
37 unsigned char l, h;
38
39 while (len != 0)
40 {
41 h = (*ibuf) / 16;
42 l = (*ibuf) % 16;
43
44 if( h < 10 )
45 *obuf++ = '0' + h;
46 else
47 *obuf++ = 'a' + h - 10;
48
49 if( l < 10 )
50 *obuf++ = '0' + l;
51 else
52 *obuf++ = 'a' + l - 10;
53
54 ++ibuf;
55 len--;
56 }
57}
Paul Bakker9dcc3222011-03-08 14:16:06 +000058
59/**
60 * This function just returns data from rand().
61 *
62 * rng_state shall be NULL.
63 */
64static int rnd_std_rand( void *rng_state )
65{
66 if( rng_state != NULL )
67 rng_state = NULL;
68
69 return( rand() );
70}
71
72/**
73 * This function only returns zeros
74 *
75 * rng_state shall be NULL.
76 */
77static int rnd_zero_rand( void *rng_state )
78{
79 if( rng_state != NULL )
80 rng_state = NULL;
81
82 return( 0 );
83}
84
85typedef struct
86{
87 unsigned char *buf;
88 int length;
89 int per_call;
90} rnd_info;
91
92/**
93 * This function returns random based on a buffer it receives.
94 *
95 * rng_state shall be a pointer to a rnd_buf structure.
96 *
97 * After the buffer is empty it will return rand();
98 */
99static int rnd_buffer_rand( void *rng_state )
100{
101 rnd_info *info = (rnd_info *) rng_state;
102 int res;
103
104 if( rng_state == NULL )
105 return( rand() );
106
107 res = rand();
108
109 if( info->length >= info->per_call )
110 {
111 memcpy( &res, info->buf, info->per_call );
112 info->buf += info->per_call;
113 info->length -= info->per_call;
114 }
115 else if( info->length > 0 )
116 {
117 memcpy( &res, info->buf, info->length );
118 info->length = 0;
119 }
120
121 return( res );
122}