diff options
Diffstat (limited to 'src/lib/codec/base64/base64.cpp')
-rw-r--r-- | src/lib/codec/base64/base64.cpp | 245 |
1 files changed, 245 insertions, 0 deletions
diff --git a/src/lib/codec/base64/base64.cpp b/src/lib/codec/base64/base64.cpp new file mode 100644 index 000000000..b66478d2b --- /dev/null +++ b/src/lib/codec/base64/base64.cpp @@ -0,0 +1,245 @@ +/* +* Base64 Encoding and Decoding +* (C) 2010 Jack Lloyd +* +* Distributed under the terms of the Botan license +*/ + +#include <botan/base64.h> +#include <botan/mem_ops.h> +#include <botan/internal/rounding.h> +#include <stdexcept> + +namespace Botan { + +namespace { + +static const byte BIN_TO_BASE64[64] = { + 'A', 'B', 'C', 'D', 'E', 'F', 'G', 'H', 'I', 'J', 'K', 'L', 'M', + 'N', 'O', 'P', 'Q', 'R', 'S', 'T', 'U', 'V', 'W', 'X', 'Y', 'Z', + 'a', 'b', 'c', 'd', 'e', 'f', 'g', 'h', 'i', 'j', 'k', 'l', 'm', + 'n', 'o', 'p', 'q', 'r', 's', 't', 'u', 'v', 'w', 'x', 'y', 'z', + '0', '1', '2', '3', '4', '5', '6', '7', '8', '9', '+', '/' +}; + +void do_base64_encode(char out[4], const byte in[3]) + { + out[0] = BIN_TO_BASE64[((in[0] & 0xFC) >> 2)]; + out[1] = BIN_TO_BASE64[((in[0] & 0x03) << 4) | (in[1] >> 4)]; + out[2] = BIN_TO_BASE64[((in[1] & 0x0F) << 2) | (in[2] >> 6)]; + out[3] = BIN_TO_BASE64[((in[2] & 0x3F) )]; + } + +} + +size_t base64_encode(char out[], + const byte in[], + size_t input_length, + size_t& input_consumed, + bool final_inputs) + { + input_consumed = 0; + + size_t input_remaining = input_length; + size_t output_produced = 0; + + while(input_remaining >= 3) + { + do_base64_encode(out + output_produced, in + input_consumed); + + input_consumed += 3; + output_produced += 4; + input_remaining -= 3; + } + + if(final_inputs && input_remaining) + { + byte remainder[3] = { 0 }; + for(size_t i = 0; i != input_remaining; ++i) + remainder[i] = in[input_consumed + i]; + + do_base64_encode(out + output_produced, remainder); + + size_t empty_bits = 8 * (3 - input_remaining); + size_t index = output_produced + 4 - 1; + while(empty_bits >= 8) + { + out[index--] = '='; + empty_bits -= 6; + } + + input_consumed += input_remaining; + output_produced += 4; + } + + return output_produced; + } + +std::string base64_encode(const byte input[], + size_t input_length) + { + std::string output((round_up<size_t>(input_length, 3) / 3) * 4, 0); + + size_t consumed = 0; + size_t produced = base64_encode(&output[0], + input, input_length, + consumed, true); + + BOTAN_ASSERT_EQUAL(consumed, input_length, "Consumed the entire input"); + BOTAN_ASSERT_EQUAL(produced, output.size(), "Produced expected size"); + + return output; + } + +size_t base64_decode(byte output[], + const char input[], + size_t input_length, + size_t& input_consumed, + bool final_inputs, + bool ignore_ws) + { + /* + * Base64 Decoder Lookup Table + * Warning: assumes ASCII encodings + */ + static const byte BASE64_TO_BIN[256] = { + 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0x80, + 0x80, 0xFF, 0xFF, 0x80, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, + 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, + 0xFF, 0xFF, 0x80, 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, 0x81, 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 }; + + byte* out_ptr = output; + byte decode_buf[4]; + size_t decode_buf_pos = 0; + size_t final_truncate = 0; + + clear_mem(output, input_length * 3 / 4); + + for(size_t i = 0; i != input_length; ++i) + { + const byte bin = BASE64_TO_BIN[static_cast<byte>(input[i])]; + + if(bin <= 0x3F) + { + decode_buf[decode_buf_pos] = bin; + decode_buf_pos += 1; + } + else if(!(bin == 0x81 || (bin == 0x80 && ignore_ws))) + { + std::string bad_char(1, input[i]); + if(bad_char == "\t") + bad_char = "\\t"; + else if(bad_char == "\n") + bad_char = "\\n"; + else if(bad_char == "\r") + bad_char = "\\r"; + + throw std::invalid_argument( + std::string("base64_decode: invalid base64 character '") + + bad_char + "'"); + } + + /* + * If we're at the end of the input, pad with 0s and truncate + */ + if(final_inputs && (i == input_length - 1)) + { + if(decode_buf_pos) + { + for(size_t i = decode_buf_pos; i != 4; ++i) + decode_buf[i] = 0; + final_truncate = (4 - decode_buf_pos); + decode_buf_pos = 4; + } + } + + if(decode_buf_pos == 4) + { + out_ptr[0] = (decode_buf[0] << 2) | (decode_buf[1] >> 4); + out_ptr[1] = (decode_buf[1] << 4) | (decode_buf[2] >> 2); + out_ptr[2] = (decode_buf[2] << 6) | decode_buf[3]; + + out_ptr += 3; + decode_buf_pos = 0; + input_consumed = i+1; + } + } + + while(input_consumed < input_length && + BASE64_TO_BIN[static_cast<byte>(input[input_consumed])] == 0x80) + { + ++input_consumed; + } + + size_t written = (out_ptr - output) - final_truncate; + + return written; + } + +size_t base64_decode(byte output[], + const char input[], + size_t input_length, + bool ignore_ws) + { + size_t consumed = 0; + size_t written = base64_decode(output, input, input_length, + consumed, true, ignore_ws); + + if(consumed != input_length) + throw std::invalid_argument("base64_decode: input did not have full bytes"); + + return written; + } + +size_t base64_decode(byte output[], + const std::string& input, + bool ignore_ws) + { + return base64_decode(output, &input[0], input.length(), ignore_ws); + } + +secure_vector<byte> base64_decode(const char input[], + size_t input_length, + bool ignore_ws) + { + secure_vector<byte> bin((round_up<size_t>(input_length, 4) * 3) / 4); + + size_t written = base64_decode(&bin[0], + input, + input_length, + ignore_ws); + + bin.resize(written); + return bin; + } + +secure_vector<byte> base64_decode(const std::string& input, + bool ignore_ws) + { + return base64_decode(&input[0], input.size(), ignore_ws); + } + + +} |