diff options
Diffstat (limited to 'comm/third_party/botan/src/lib/codec/hex/hex.cpp')
-rw-r--r-- | comm/third_party/botan/src/lib/codec/hex/hex.cpp | 210 |
1 files changed, 210 insertions, 0 deletions
diff --git a/comm/third_party/botan/src/lib/codec/hex/hex.cpp b/comm/third_party/botan/src/lib/codec/hex/hex.cpp new file mode 100644 index 0000000000..1ae21f398b --- /dev/null +++ b/comm/third_party/botan/src/lib/codec/hex/hex.cpp @@ -0,0 +1,210 @@ +/* +* Hex Encoding and Decoding +* (C) 2010,2020 Jack Lloyd +* +* Botan is released under the Simplified BSD License (see license.txt) +*/ + +#include <botan/hex.h> +#include <botan/mem_ops.h> +#include <botan/exceptn.h> +#include <botan/internal/ct_utils.h> + +namespace Botan { + +namespace { + +char hex_encode_nibble(uint8_t n, bool uppercase) + { + BOTAN_DEBUG_ASSERT(n <= 15); + + const auto in_09 = CT::Mask<uint8_t>::is_lt(n, 10); + + const char c_09 = n + '0'; + const char c_af = n + (uppercase ? 'A' : 'a') - 10; + + return in_09.select(c_09, c_af); + } + +} + +void hex_encode(char output[], + const uint8_t input[], + size_t input_length, + bool uppercase) + { + for(size_t i = 0; i != input_length; ++i) + { + const uint8_t n0 = (input[i] >> 4) & 0xF; + const uint8_t n1 = (input[i] ) & 0xF; + + output[2*i ] = hex_encode_nibble(n0, uppercase); + output[2*i+1] = hex_encode_nibble(n1, uppercase); + } + } + +std::string hex_encode(const uint8_t input[], + size_t input_length, + bool uppercase) + { + std::string output(2 * input_length, 0); + + if(input_length) + hex_encode(&output.front(), input, input_length, uppercase); + + return output; + } + +namespace { + +uint8_t hex_char_to_bin(char input) + { + const uint8_t c = static_cast<uint8_t>(input); + + const auto is_alpha_upper = CT::Mask<uint8_t>::is_within_range(c, uint8_t('A'), uint8_t('F')); + const auto is_alpha_lower = CT::Mask<uint8_t>::is_within_range(c, uint8_t('a'), uint8_t('f')); + const auto is_decimal = CT::Mask<uint8_t>::is_within_range(c, uint8_t('0'), uint8_t('9')); + + const auto is_whitespace = CT::Mask<uint8_t>::is_any_of(c, { + uint8_t(' '), uint8_t('\t'), uint8_t('\n'), uint8_t('\r') + }); + + const uint8_t c_upper = c - uint8_t('A') + 10; + const uint8_t c_lower = c - uint8_t('a') + 10; + const uint8_t c_decim = c - uint8_t('0'); + + uint8_t ret = 0xFF; // default value + + ret = is_alpha_upper.select(c_upper, ret); + ret = is_alpha_lower.select(c_lower, ret); + ret = is_decimal.select(c_decim, ret); + ret = is_whitespace.select(0x80, ret); + + return ret; + } + +} + + +size_t hex_decode(uint8_t output[], + const char input[], + size_t input_length, + size_t& input_consumed, + bool ignore_ws) + { + uint8_t* out_ptr = output; + bool top_nibble = true; + + clear_mem(output, input_length / 2); + + for(size_t i = 0; i != input_length; ++i) + { + const uint8_t bin = hex_char_to_bin(input[i]); + + if(bin >= 0x10) + { + if(bin == 0x80 && ignore_ws) + continue; + + std::string bad_char(1, input[i]); + if(bad_char == "\t") + bad_char = "\\t"; + else if(bad_char == "\n") + bad_char = "\\n"; + + throw Invalid_Argument( + std::string("hex_decode: invalid hex character '") + + bad_char + "'"); + } + + if(top_nibble) + *out_ptr |= bin << 4; + else + *out_ptr |= bin; + + top_nibble = !top_nibble; + if(top_nibble) + ++out_ptr; + } + + input_consumed = input_length; + size_t written = (out_ptr - output); + + /* + * We only got half of a uint8_t at the end; zap the half-written + * output and mark it as unread + */ + if(!top_nibble) + { + *out_ptr = 0; + input_consumed -= 1; + } + + return written; + } + +size_t hex_decode(uint8_t output[], + const char input[], + size_t input_length, + bool ignore_ws) + { + size_t consumed = 0; + size_t written = hex_decode(output, input, input_length, + consumed, ignore_ws); + + if(consumed != input_length) + throw Invalid_Argument("hex_decode: input did not have full bytes"); + + return written; + } + +size_t hex_decode(uint8_t output[], + const std::string& input, + bool ignore_ws) + { + return hex_decode(output, input.data(), input.length(), ignore_ws); + } + +secure_vector<uint8_t> hex_decode_locked(const char input[], + size_t input_length, + bool ignore_ws) + { + secure_vector<uint8_t> bin(1 + input_length / 2); + + size_t written = hex_decode(bin.data(), + input, + input_length, + ignore_ws); + + bin.resize(written); + return bin; + } + +secure_vector<uint8_t> hex_decode_locked(const std::string& input, + bool ignore_ws) + { + return hex_decode_locked(input.data(), input.size(), ignore_ws); + } + +std::vector<uint8_t> hex_decode(const char input[], + size_t input_length, + bool ignore_ws) + { + std::vector<uint8_t> bin(1 + input_length / 2); + + size_t written = hex_decode(bin.data(), + input, + input_length, + ignore_ws); + + bin.resize(written); + return bin; + } + +std::vector<uint8_t> hex_decode(const std::string& input, + bool ignore_ws) + { + return hex_decode(input.data(), input.size(), ignore_ws); + } + +} |