2 * Base64 encoding/decoding (RFC1341)
3 * Copyright (c) 2005, Jouni Malinen <j@w1.fi>
5 * This program is free software; you can redistribute it and/or modify
6 * it under the terms of the GNU General Public License version 2 as
7 * published by the Free Software Foundation.
9 * Alternatively, this software may be distributed under the terms of BSD
12 * See README and COPYING for more details.
20 static const unsigned char base64_table[65] =
21 "ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz0123456789+/";
24 * base64_encode - Base64 encode
25 * @src: Data to be encoded
26 * @len: Length of the data to be encoded
27 * @out_len: Pointer to output length variable, or %NULL if not used
28 * Returns: Allocated buffer of out_len bytes of encoded data,
31 * Caller is responsible for freeing the returned buffer. Returned buffer is
32 * nul terminated to make it easier to use as a C string. The nul terminator is
33 * not included in out_len.
35 unsigned char * base64_encode(const unsigned char *src, size_t len,
38 unsigned char *out, *pos;
39 const unsigned char *end, *in;
43 olen = len * 4 / 3 + 4; /* 3-byte blocks to 4-byte */
44 olen += olen / 72; /* line feeds */
45 olen++; /* nul termination */
47 return NULL; /* integer overflow */
48 out = os_malloc(olen);
56 while (end - in >= 3) {
57 *pos++ = base64_table[in[0] >> 2];
58 *pos++ = base64_table[((in[0] & 0x03) << 4) | (in[1] >> 4)];
59 *pos++ = base64_table[((in[1] & 0x0f) << 2) | (in[2] >> 6)];
60 *pos++ = base64_table[in[2] & 0x3f];
70 *pos++ = base64_table[in[0] >> 2];
72 *pos++ = base64_table[(in[0] & 0x03) << 4];
75 *pos++ = base64_table[((in[0] & 0x03) << 4) |
77 *pos++ = base64_table[(in[1] & 0x0f) << 2];
94 * base64_decode - Base64 decode
95 * @src: Data to be decoded
96 * @len: Length of the data to be decoded
97 * @out_len: Pointer to output length variable
98 * Returns: Allocated buffer of out_len bytes of decoded data,
101 * Caller is responsible for freeing the returned buffer.
103 unsigned char * base64_decode(const unsigned char *src, size_t len,
106 unsigned char dtable[256], *out, *pos, in[4], block[4], tmp;
107 size_t i, count, olen;
109 os_memset(dtable, 0x80, 256);
110 for (i = 0; i < sizeof(base64_table) - 1; i++)
111 dtable[base64_table[i]] = (unsigned char) i;
115 for (i = 0; i < len; i++) {
116 if (dtable[src[i]] != 0x80)
120 if (count == 0 || count % 4)
123 olen = count / 4 * 3;
124 pos = out = os_malloc(olen);
129 for (i = 0; i < len; i++) {
130 tmp = dtable[src[i]];
138 *pos++ = (block[0] << 2) | (block[1] >> 4);
139 *pos++ = (block[1] << 4) | (block[2] >> 2);
140 *pos++ = (block[2] << 6) | block[3];
148 else if (in[3] == '=')
152 *out_len = pos - out;
159 int main(int argc, char *argv[])
163 unsigned char *buf, *e;
166 printf("Usage: base64 <encode|decode> <in file> <out file>\n");
170 buf = os_readfile(argv[2], &len);
174 if (strcmp(argv[1], "encode") == 0)
175 e = base64_encode(buf, len, &elen);
177 e = base64_decode(buf, len, &elen);
180 f = fopen(argv[3], "w");
183 fwrite(e, 1, elen, f);
189 #endif /* TEST_MAIN */