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author | lloyd <[email protected]> | 2015-02-05 07:44:25 +0000 |
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committer | lloyd <[email protected]> | 2015-02-05 07:44:25 +0000 |
commit | cb0f83ae63c4555cbdd0607e3a5f6e9260c0d19c (patch) | |
tree | 4981027a25fa8074177b97c3a3ca7431f3337deb /src/lib/hash/checksum/adler32/adler32.cpp | |
parent | 2c14faf0aa1cfe0f8d70af1938dcad5b4d6d3b59 (diff) |
Clean up root dir, remove some unneeded dependencies
Diffstat (limited to 'src/lib/hash/checksum/adler32/adler32.cpp')
-rw-r--r-- | src/lib/hash/checksum/adler32/adler32.cpp | 83 |
1 files changed, 83 insertions, 0 deletions
diff --git a/src/lib/hash/checksum/adler32/adler32.cpp b/src/lib/hash/checksum/adler32/adler32.cpp new file mode 100644 index 000000000..f2385c5b8 --- /dev/null +++ b/src/lib/hash/checksum/adler32/adler32.cpp @@ -0,0 +1,83 @@ +/* +* Adler32 +* (C) 1999-2007 Jack Lloyd +* +* Botan is released under the Simplified BSD License (see license.txt) +*/ + +#include <botan/internal/hash_utils.h> +#include <botan/adler32.h> + +namespace Botan { + +BOTAN_REGISTER_HASH_NOARGS(Adler32); + +namespace { + +void adler32_update(const byte input[], size_t length, + u16bit& S1, u16bit& S2) + { + u32bit S1x = S1; + u32bit S2x = S2; + + while(length >= 16) + { + S1x += input[ 0]; S2x += S1x; + S1x += input[ 1]; S2x += S1x; + S1x += input[ 2]; S2x += S1x; + S1x += input[ 3]; S2x += S1x; + S1x += input[ 4]; S2x += S1x; + S1x += input[ 5]; S2x += S1x; + S1x += input[ 6]; S2x += S1x; + S1x += input[ 7]; S2x += S1x; + S1x += input[ 8]; S2x += S1x; + S1x += input[ 9]; S2x += S1x; + S1x += input[10]; S2x += S1x; + S1x += input[11]; S2x += S1x; + S1x += input[12]; S2x += S1x; + S1x += input[13]; S2x += S1x; + S1x += input[14]; S2x += S1x; + S1x += input[15]; S2x += S1x; + input += 16; + length -= 16; + } + + for(size_t j = 0; j != length; ++j) + { + S1x += input[j]; + S2x += S1x; + } + + S1 = S1x % 65521; + S2 = S2x % 65521; + } + +} + +/* +* Update an Adler32 Checksum +*/ +void Adler32::add_data(const byte input[], size_t length) + { + const size_t PROCESS_AMOUNT = 5552; + + while(length >= PROCESS_AMOUNT) + { + adler32_update(input, PROCESS_AMOUNT, S1, S2); + input += PROCESS_AMOUNT; + length -= PROCESS_AMOUNT; + } + + adler32_update(input, length, S1, S2); + } + +/* +* Finalize an Adler32 Checksum +*/ +void Adler32::final_result(byte output[]) + { + store_be(output, S2, S1); + clear(); + } + +} |