diff options
Diffstat (limited to 'src/base64.c')
| -rw-r--r-- | src/base64.c | 94 |
1 files changed, 51 insertions, 43 deletions
diff --git a/src/base64.c b/src/base64.c index 763c2d2e..6f292d02 100644 --- a/src/base64.c +++ b/src/base64.c @@ -32,7 +32,7 @@ @see <a href="http://tools.ietf.org/html/rfc3548#section-3">RFC3548 S3</a>. */ static const uint8_t b64_map[] = - "ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz0123456789+/"; + "ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz0123456789+/"; /** Base64 decoding table. @@ -42,27 +42,28 @@ static const uint8_t b64_map[] = A '$' is a placeholder for characters not in the base64 alphabet. */ static const char b64_unmap[] = - "$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$m$$$ncdefghijkl$$$$$$" - "$/0123456789:;<=>?@ABCDEFGH$$$$$$IJKLMNOPQRSTUVWXYZ[\\]^_`ab$$$$" - "$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$" - "$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$"; + "$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$m$$$ncdefghijkl$$$$$$" + "$/0123456789:;<=>?@ABCDEFGH$$$$$$IJKLMNOPQRSTUVWXYZ[\\]^_`ab$$$$" + "$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$" + "$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$"; /** Encode 3 raw bytes to 4 base64 characters. */ static inline void encode_chunk(uint8_t out[4], const uint8_t in[3], size_t n_in) { - out[0] = b64_map[in[0] >> 2]; - out[1] = b64_map[((in[0] & 0x03) << 4) | ((in[1] & 0xF0) >> 4)]; - out[2] = ((n_in > 1) - ? (b64_map[((in[1] & 0x0F) << 2) | ((in[2] & 0xC0) >> 6)]) - : (uint8_t)'='); - out[3] = ((n_in > 2) ? b64_map[in[2] & 0x3F] : (uint8_t)'='); + out[0] = b64_map[in[0] >> 2]; + out[1] = b64_map[((in[0] & 0x03) << 4) | ((in[1] & 0xF0) >> 4)]; + + out[2] = (n_in > 1) ? (b64_map[((in[1] & 0x0F) << 2) | ((in[2] & 0xC0) >> 6)]) + : (uint8_t)'='; + + out[3] = ((n_in > 2) ? b64_map[in[2] & 0x3F] : (uint8_t)'='); } size_t serd_base64_get_length(const size_t size, const bool wrap_lines) { - return (size + 2) / 3 * 4 + (wrap_lines * ((size - 1) / 57)); + return (size + 2) / 3 * 4 + (wrap_lines * ((size - 1) / 57)); } bool @@ -71,54 +72,61 @@ serd_base64_encode(uint8_t* const str, const size_t size, const bool wrap_lines) { - bool has_newline = false; - for (size_t i = 0, j = 0; i < size; i += 3, j += 4) { - uint8_t in[4] = { 0, 0, 0, 0 }; - size_t n_in = MIN(3, size - i); - memcpy(in, (const uint8_t*)buf + i, n_in); + bool has_newline = false; + + for (size_t i = 0, j = 0; i < size; i += 3, j += 4) { + uint8_t in[4] = {0, 0, 0, 0}; + size_t n_in = MIN(3, size - i); + memcpy(in, (const uint8_t*)buf + i, n_in); - if (wrap_lines && i > 0 && (i % 57) == 0) { - str[j++] = '\n'; - has_newline = true; - } + if (wrap_lines && i > 0 && (i % 57) == 0) { + str[j++] = '\n'; + has_newline = true; + } - encode_chunk(str + j, in, n_in); - } + encode_chunk(str + j, in, n_in); + } - return has_newline; + return has_newline; } static inline uint8_t unmap(const uint8_t in) { - return (uint8_t)(b64_unmap[in] - 47); + return (uint8_t)(b64_unmap[in] - 47); } /** Decode 4 base64 characters to 3 raw bytes. */ static inline size_t decode_chunk(const uint8_t in[4], uint8_t out[3]) { - out[0] = (uint8_t)(((unmap(in[0]) << 2)) | unmap(in[1]) >> 4); - out[1] = (uint8_t)(((unmap(in[1]) << 4) & 0xF0) | unmap(in[2]) >> 2); - out[2] = (uint8_t)(((unmap(in[2]) << 6) & 0xC0) | unmap(in[3])); - return 1 + (in[2] != '=') + ((in[2] != '=') && (in[3] != '=')); + out[0] = (uint8_t)(((unmap(in[0]) << 2)) | unmap(in[1]) >> 4); + out[1] = (uint8_t)(((unmap(in[1]) << 4) & 0xF0) | unmap(in[2]) >> 2); + out[2] = (uint8_t)(((unmap(in[2]) << 6) & 0xC0) | unmap(in[3])); + return 1 + (in[2] != '=') + ((in[2] != '=') && (in[3] != '=')); } void* serd_base64_decode(const uint8_t* str, size_t len, size_t* size) { - void* buf = malloc((len * 3) / 4 + 2); - *size = 0; - for (size_t i = 0, j = 0; i < len; j += 3) { - uint8_t in[] = "===="; - size_t n_in = 0; - for (; i < len && n_in < 4; ++n_in) { - for (; i < len && !is_base64(str[i]); ++i) {} // Skip junk - in[n_in] = str[i++]; - } - if (n_in > 1) { - *size += decode_chunk(in, (uint8_t*)buf + j); - } - } - return buf; + void* buf = malloc((len * 3) / 4 + 2); + + *size = 0; + for (size_t i = 0, j = 0; i < len; j += 3) { + uint8_t in[] = "===="; + size_t n_in = 0; + for (; i < len && n_in < 4; ++n_in) { + for (; i < len && !is_base64(str[i]); ++i) { + // Skip junk + } + + in[n_in] = str[i++]; + } + + if (n_in > 1) { + *size += decode_chunk(in, (uint8_t*)buf + j); + } + } + + return buf; } |