diff options
Diffstat (limited to 'comm/third_party/botan/src/lib/codec/base32/base32.cpp')
-rw-r--r-- | comm/third_party/botan/src/lib/codec/base32/base32.cpp | 233 |
1 files changed, 233 insertions, 0 deletions
diff --git a/comm/third_party/botan/src/lib/codec/base32/base32.cpp b/comm/third_party/botan/src/lib/codec/base32/base32.cpp new file mode 100644 index 0000000000..224dae9916 --- /dev/null +++ b/comm/third_party/botan/src/lib/codec/base32/base32.cpp @@ -0,0 +1,233 @@ +/* +* Base32 Encoding and Decoding +* (C) 2018 Erwan Chaussy +* (C) 2018,2020 Jack Lloyd +* +* Botan is released under the Simplified BSD License (see license.txt) +*/ + +#include <botan/base32.h> +#include <botan/internal/codec_base.h> +#include <botan/internal/rounding.h> +#include <botan/internal/ct_utils.h> + +namespace Botan { + +namespace { + +class Base32 final + { + public: + static inline std::string name() noexcept + { + return "base32"; + } + + static inline size_t encoding_bytes_in() noexcept + { + return m_encoding_bytes_in; + } + static inline size_t encoding_bytes_out() noexcept + { + return m_encoding_bytes_out; + } + + static inline size_t decoding_bytes_in() noexcept + { + return m_encoding_bytes_out; + } + static inline size_t decoding_bytes_out() noexcept + { + return m_encoding_bytes_in; + } + + static inline size_t bits_consumed() noexcept + { + return m_encoding_bits; + } + static inline size_t remaining_bits_before_padding() noexcept + { + return m_remaining_bits_before_padding; + } + + static inline size_t encode_max_output(size_t input_length) + { + return (round_up(input_length, m_encoding_bytes_in) / m_encoding_bytes_in) * m_encoding_bytes_out; + } + static inline size_t decode_max_output(size_t input_length) + { + return (round_up(input_length, m_encoding_bytes_out) * m_encoding_bytes_in) / m_encoding_bytes_out; + } + + static void encode(char out[8], const uint8_t in[5]) noexcept; + + static uint8_t lookup_binary_value(char input) noexcept; + + static bool check_bad_char(uint8_t bin, char input, bool ignore_ws); + + static void decode(uint8_t* out_ptr, const uint8_t decode_buf[8]) + { + out_ptr[0] = (decode_buf[0] << 3) | (decode_buf[1] >> 2); + out_ptr[1] = (decode_buf[1] << 6) | (decode_buf[2] << 1) | (decode_buf[3] >> 4); + out_ptr[2] = (decode_buf[3] << 4) | (decode_buf[4] >> 1); + out_ptr[3] = (decode_buf[4] << 7) | (decode_buf[5] << 2) | (decode_buf[6] >> 3); + out_ptr[4] = (decode_buf[6] << 5) | decode_buf[7]; + } + + static inline size_t bytes_to_remove(size_t final_truncate) + { + return final_truncate ? (final_truncate / 2) + 1 : 0; + } + + private: + static const size_t m_encoding_bits = 5; + static const size_t m_remaining_bits_before_padding = 6; + + static const size_t m_encoding_bytes_in = 5; + static const size_t m_encoding_bytes_out = 8; + }; + +namespace { + +char lookup_base32_char(uint8_t x) + { + BOTAN_DEBUG_ASSERT(x < 32); + + const auto in_AZ = CT::Mask<uint8_t>::is_lt(x, 26); + + const char c_AZ = 'A' + x; + const char c_27 = '2' + (x - 26); + + return in_AZ.select(c_AZ, c_27); + } + +} + +//static +void Base32::encode(char out[8], const uint8_t in[5]) noexcept + { + const uint8_t b0 = (in[0] & 0xF8) >> 3; + const uint8_t b1 = ((in[0] & 0x07) << 2) | (in[1] >> 6); + const uint8_t b2 = ((in[1] & 0x3E) >> 1); + const uint8_t b3 = ((in[1] & 0x01) << 4) | (in[2] >> 4); + const uint8_t b4 = ((in[2] & 0x0F) << 1) | (in[3] >> 7); + const uint8_t b5 = ((in[3] & 0x7C) >> 2); + const uint8_t b6 = ((in[3] & 0x03) << 3) | (in[4] >> 5); + const uint8_t b7 = in[4] & 0x1F; + + out[0] = lookup_base32_char(b0); + out[1] = lookup_base32_char(b1); + out[2] = lookup_base32_char(b2); + out[3] = lookup_base32_char(b3); + out[4] = lookup_base32_char(b4); + out[5] = lookup_base32_char(b5); + out[6] = lookup_base32_char(b6); + out[7] = lookup_base32_char(b7); + } + +//static +uint8_t Base32::lookup_binary_value(char input) noexcept + { + 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('Z')); + const auto is_decimal = CT::Mask<uint8_t>::is_within_range(c, uint8_t('2'), uint8_t('7')); + + const auto is_equal = CT::Mask<uint8_t>::is_equal(c, uint8_t('=')); + 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'); + const uint8_t c_decim = c - uint8_t('2') + 26; + + uint8_t ret = 0xFF; // default value + + ret = is_alpha_upper.select(c_upper, ret); + ret = is_decimal.select(c_decim, ret); + ret = is_equal.select(0x81, ret); + ret = is_whitespace.select(0x80, ret); + + return ret; + } + +//static +bool Base32::check_bad_char(uint8_t bin, char input, bool ignore_ws) + { + if(bin <= 0x1F) + { + return true; + } + else if(!(bin == 0x81 || (bin == 0x80 && ignore_ws))) + { + std::string bad_char(1, input); + if(bad_char == "\t") + { bad_char = "\\t"; } + else if(bad_char == "\n") + { bad_char = "\\n"; } + else if(bad_char == "\r") + { bad_char = "\\r"; } + + throw Invalid_Argument( + std::string("base32_decode: invalid base32 character '") + + bad_char + "'"); + } + return false; + } + +} + +size_t base32_encode(char out[], + const uint8_t in[], + size_t input_length, + size_t& input_consumed, + bool final_inputs) + { + return base_encode(Base32(), out, in, input_length, input_consumed, final_inputs); + } + +std::string base32_encode(const uint8_t input[], + size_t input_length) + { + return base_encode_to_string(Base32(), input, input_length); + } + +size_t base32_decode(uint8_t out[], + const char in[], + size_t input_length, + size_t& input_consumed, + bool final_inputs, + bool ignore_ws) + { + return base_decode(Base32(), out, in, input_length, input_consumed, final_inputs, ignore_ws); + } + +size_t base32_decode(uint8_t output[], + const char input[], + size_t input_length, + bool ignore_ws) + { + return base_decode_full(Base32(), output, input, input_length, ignore_ws); + } + +size_t base32_decode(uint8_t output[], + const std::string& input, + bool ignore_ws) + { + return base32_decode(output, input.data(), input.length(), ignore_ws); + } + +secure_vector<uint8_t> base32_decode(const char input[], + size_t input_length, + bool ignore_ws) + { + return base_decode_to_vec<secure_vector<uint8_t>>(Base32(), input, input_length, ignore_ws); + } + +secure_vector<uint8_t> base32_decode(const std::string& input, + bool ignore_ws) + { + return base32_decode(input.data(), input.size(), ignore_ws); + } + +} |