| /* |
| * Base64 encoding: Copyright (c) 2005-2011, Jouni Malinen <j@w1.fi> |
| * This software may be distributed under the terms of the BSD license. |
| * |
| * Base64 decoding: Copyright (c) 2016, polfosol |
| * Posted at https://stackoverflow.com/a/37109258 under the CC-BY-SA Creative |
| * Commons license. |
| */ |
| |
| #include "base64.h" |
| #include <open62541/types.h> |
| |
| static const unsigned char base64_table[65] = |
| "ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz0123456789+/"; |
| |
| unsigned char * |
| UA_base64(const unsigned char *src, size_t len, size_t *out_len) { |
| if(len == 0) { |
| *out_len = 0; |
| return (unsigned char*)UA_EMPTY_ARRAY_SENTINEL; |
| } |
| |
| size_t olen = 4*((len + 2) / 3); /* 3-byte blocks to 4-byte */ |
| if(olen < len) |
| return NULL; /* integer overflow */ |
| |
| unsigned char *out = (unsigned char*)UA_malloc(olen); |
| if(!out) |
| return NULL; |
| |
| const unsigned char *end = src + len; |
| const unsigned char *in = src; |
| unsigned char *pos = out; |
| while(end - in >= 3) { |
| *pos++ = base64_table[in[0] >> 2]; |
| *pos++ = base64_table[((in[0] & 0x03) << 4) | (in[1] >> 4)]; |
| *pos++ = base64_table[((in[1] & 0x0f) << 2) | (in[2] >> 6)]; |
| *pos++ = base64_table[in[2] & 0x3f]; |
| in += 3; |
| } |
| |
| if(end - in) { |
| *pos++ = base64_table[in[0] >> 2]; |
| if(end - in == 1) { |
| *pos++ = base64_table[(in[0] & 0x03) << 4]; |
| *pos++ = '='; |
| } else { |
| *pos++ = base64_table[((in[0] & 0x03) << 4) | (in[1] >> 4)]; |
| *pos++ = base64_table[(in[1] & 0x0f) << 2]; |
| } |
| *pos++ = '='; |
| } |
| |
| *out_len = (size_t)(pos - out); |
| return out; |
| } |
| |
| static const uint32_t from_b64[256] = { |
| 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, |
| 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, |
| 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 62, 63, 62, 62, 63, |
| 52, 53, 54, 55, 56, 57, 58, 59, 60, 61, 0, 0, 0, 0, 0, 0, |
| 0, 0, 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, 0, 0, 0, 0, 63, |
| 0, 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}; |
| |
| unsigned char * |
| UA_unbase64(const unsigned char *src, size_t len, size_t *out_len) { |
| if(len == 0) { |
| *out_len = 0; |
| return (unsigned char*)UA_EMPTY_ARRAY_SENTINEL; |
| } |
| |
| const unsigned char *p = src; |
| size_t pad1 = len % 4 || p[len - 1] == '='; |
| size_t pad2 = pad1 && (len % 4 > 2 || p[len - 2] != '='); |
| const size_t last = (len - pad1) / 4 << 2; |
| |
| unsigned char *str = (unsigned char*)UA_malloc(last / 4 * 3 + pad1 + pad2); |
| if(!str) |
| return NULL; |
| |
| unsigned char *pos = str; |
| for(size_t i = 0; i < last; i += 4) { |
| uint32_t n = from_b64[p[i]] << 18 | from_b64[p[i + 1]] << 12 | |
| from_b64[p[i + 2]] << 6 | from_b64[p[i + 3]]; |
| *pos++ = (unsigned char)(n >> 16); |
| *pos++ = (unsigned char)(n >> 8 & 0xFF); |
| *pos++ = (unsigned char)(n & 0xFF); |
| } |
| |
| if(pad1) { |
| uint32_t n = from_b64[p[last]] << 18 | from_b64[p[last + 1]] << 12; |
| *pos++ = (unsigned char)(n >> 16); |
| if(pad2) { |
| n |= from_b64[p[last + 2]] << 6; |
| *pos++ = (unsigned char)(n >> 8 & 0xFF); |
| } |
| } |
| |
| *out_len = (uintptr_t)(pos - str); |
| return str; |
| } |