bee2-rs 0.2.1

Bindings for cryptographic library Bee2
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
166
167
168
169
170
171
172
173
174
175
176
177

/*
*******************************************************************************
\file b64.c
\brief The Base64 encoding
\project bee2 [cryptographic library]
\created 2016.06.16
\version 2025.06.10
\copyright The Bee2 authors
\license Licensed under the Apache License, Version 2.0 (see LICENSE.txt).
*******************************************************************************
*/

#include "bee2/core/b64.h"
#include "bee2/core/mem.h"
#include "bee2/core/str.h"
#include "bee2/core/util.h"

/*
*******************************************************************************
Таблицы

\todo Кодировка base64url: + меняется на -, / меняется на _.
*******************************************************************************
*/

static const char b64_alphabet[] = 
	"ABCDEFGHIJKLMNOPQRSTUVWXYZ"
	"abcdefghijklmnopqrstuvwxyz"
	"0123456789+/";

static const octet b64_dec_table[256] = {
	0xFF,0xFF,0xFF,0xFF,0xFF,0xFF,0xFF,0xFF,0xFF,0xFF,0xFF,0xFF,0xFF,0xFF,0xFF,0xFF,
	0xFF,0xFF,0xFF,0xFF,0xFF,0xFF,0xFF,0xFF,0xFF,0xFF,0xFF,0xFF,0xFF,0xFF,0xFF,0xFF,
	0xFF,0xFF,0xFF,0xFF,0xFF,0xFF,0xFF,0xFF,0xFF,0xFF,0xFF,0x3E,0xFF,0xFF,0xFF,0x3F,
	0x34,0x35,0x36,0x37,0x38,0x39,0x3A,0x3B,0x3C,0x3D,0xFF,0xFF,0xFF,0xFF,0xFF,0xFF,
	0xFF,0x00,0x01,0x02,0x03,0x04,0x05,0x06,0x07,0x08,0x09,0x0A,0x0B,0x0C,0x0D,0x0E,
	0x0F,0x10,0x11,0x12,0x13,0x14,0x15,0x16,0x17,0x18,0x19,0xFF,0xFF,0xFF,0xFF,0xFF,
	0xFF,0x1A,0x1B,0x1C,0x1D,0x1E,0x1F,0x20,0x21,0x22,0x23,0x24,0x25,0x26,0x27,0x28,
	0x29,0x2A,0x2B,0x2C,0x2D,0x2E,0x2F,0x30,0x31,0x32,0x33,0xFF,0xFF,0xFF,0xFF,0xFF,
	0xFF,0xFF,0xFF,0xFF,0xFF,0xFF,0xFF,0xFF,0xFF,0xFF,0xFF,0xFF,0xFF,0xFF,0xFF,0xFF,
	0xFF,0xFF,0xFF,0xFF,0xFF,0xFF,0xFF,0xFF,0xFF,0xFF,0xFF,0xFF,0xFF,0xFF,0xFF,0xFF,
	0xFF,0xFF,0xFF,0xFF,0xFF,0xFF,0xFF,0xFF,0xFF,0xFF,0xFF,0xFF,0xFF,0xFF,0xFF,0xFF,
	0xFF,0xFF,0xFF,0xFF,0xFF,0xFF,0xFF,0xFF,0xFF,0xFF,0xFF,0xFF,0xFF,0xFF,0xFF,0xFF,
	0xFF,0xFF,0xFF,0xFF,0xFF,0xFF,0xFF,0xFF,0xFF,0xFF,0xFF,0xFF,0xFF,0xFF,0xFF,0xFF,
	0xFF,0xFF,0xFF,0xFF,0xFF,0xFF,0xFF,0xFF,0xFF,0xFF,0xFF,0xFF,0xFF,0xFF,0xFF,0xFF,
	0xFF,0xFF,0xFF,0xFF,0xFF,0xFF,0xFF,0xFF,0xFF,0xFF,0xFF,0xFF,0xFF,0xFF,0xFF,0xFF,
	0xFF,0xFF,0xFF,0xFF,0xFF,0xFF,0xFF,0xFF,0xFF,0xFF,0xFF,0xFF,0xFF,0xFF,0xFF,0xFF,
};

/*
*******************************************************************************
Проверка
*******************************************************************************
*/

bool_t b64IsValid(const char* b64)
{
	size_t len;
	if (!strIsValid(b64))
		return FALSE;
	// проверить длину
	len = strLen(b64);
	if (len % 4)
		return FALSE;
	// обработать паддинг 
	if (len && b64[len - 1] == '=' && b64[--len - 1] == '=')
		--len;
	// последний блок данных из 2 октетов?
	if (len % 4 == 3)
	{
		if (b64_dec_table[(octet)b64[len - 1]] & 3)
			return FALSE;
		--len;
	}
	// последний блок данных из 1 октета?
	else if (len % 4 == 2)
	{
		if (b64_dec_table[(octet)b64[len - 1]] & 15)
			return FALSE;
		--len;
	}
	// проверить остальные символы 
	for (; len--; ++b64)
		if (b64_dec_table[(octet)*b64] == 0xFF)
			return FALSE;
	return TRUE;
}

/*
*******************************************************************************
Кодирование
*******************************************************************************
*/

void b64From(char* dest, const void* src, size_t count)
{
	register u32 block;
	ASSERT(memIsDisjoint2(src, count, dest, 4 * ((count + 2) / 3) + 1));
	for (; count >= 3; count -= 3)
	{
		block  = ((const octet*)src)[0], block <<= 8;
		block |= ((const octet*)src)[1], block <<= 8;
		block |= ((const octet*)src)[2];
		dest[3] = b64_alphabet[block & 63], block >>= 6;
		dest[2] = b64_alphabet[block & 63], block >>= 6;
		dest[1] = b64_alphabet[block & 63], block >>= 6;
		dest[0] = b64_alphabet[block];
		src = (const octet*)src + 3;
		dest += 4;
	}
	if (count == 2)
	{
		block  = ((const octet*)src)[0], block <<= 8;
		block |= ((const octet*)src)[1], block <<= 2;
		dest[3] = '=';
		dest[2] = b64_alphabet[block & 63], block >>= 6;
		dest[1] = b64_alphabet[block & 63], block >>= 6;
		dest[0] = b64_alphabet[block];
		dest += 4;
	}
	else if (count == 1)
	{
		block  = ((const octet*)src)[0], block <<= 4;
		dest[3] = dest[2] = '=';
		dest[1] = b64_alphabet[block & 63], block >>= 6;
		dest[0] = b64_alphabet[block];
		dest += 4;
	}
	*dest = '\0';
	CLEAN(block);
}

void b64To(void* dest, size_t* count, const char* src)
{
	register u32 block;
	size_t len;
	ASSERT(b64IsValid(src));
	ASSERT(memIsValid(count, sizeof(size_t)));
	ASSERT(memIsNullOrValid(dest, *count));
	// размер dest
	len = strLen(src);
	if (len && src[len - 1] == '=' && src[--len - 1] == '=')
		--len;
	ASSERT(dest ? *count >= 3 * (len / 4) + (len & 1) + (len >> 1 & 1) : TRUE);
	*count = 3 * (len / 4) + (len & 1) + (len >> 1 & 1);
	if (dest == 0)
		return;
	// декодировать
	ASSERT(memIsDisjoint2(src, strLen(src) + 1, dest, *count));
	for (; len >= 4; len -= 4)
	{
		block  = b64_dec_table[(octet)src[0]], block <<= 6;
		block |= b64_dec_table[(octet)src[1]], block <<= 6;
		block |= b64_dec_table[(octet)src[2]], block <<= 6;
		block |= b64_dec_table[(octet)src[3]];
		((octet*)dest)[2] = block & 255, block >>= 8;
		((octet*)dest)[1] = block & 255, block >>= 8;
		((octet*)dest)[0] = block;
		src += 4;
		dest = (octet*)dest + 3;
	}
	if (len == 3)
	{
		block  = b64_dec_table[(octet)src[0]], block <<= 6;
		block |= b64_dec_table[(octet)src[1]], block <<= 6;
		block |= b64_dec_table[(octet)src[2]], block >>= 2;
		((octet*)dest)[1] = block & 255, block >>= 8;
		((octet*)dest)[0] = block;
	}
	else if (len == 2)
	{
		block  = b64_dec_table[(octet)src[0]], block <<= 6;
		block |= b64_dec_table[(octet)src[1]], block >>= 4;
		((octet*)dest)[0] = block;
	}
	CLEAN(block);
}