diff options
author | lloyd <[email protected]> | 2008-09-28 19:29:24 +0000 |
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committer | lloyd <[email protected]> | 2008-09-28 19:29:24 +0000 |
commit | 9bcfe627321ddc81691b835dffaa6324ac4684a4 (patch) | |
tree | fe5e8ae9813b853549558b59833022e87e83981b /src/pk_pad/eme1 | |
parent | 9822a701516396b7de4e41339faecd48ff8dc8ff (diff) |
Move all modules into src/ directory
Diffstat (limited to 'src/pk_pad/eme1')
-rw-r--r-- | src/pk_pad/eme1/eme1.cpp | 95 | ||||
-rw-r--r-- | src/pk_pad/eme1/eme1.h | 35 | ||||
-rw-r--r-- | src/pk_pad/eme1/modinfo.txt | 10 |
3 files changed, 140 insertions, 0 deletions
diff --git a/src/pk_pad/eme1/eme1.cpp b/src/pk_pad/eme1/eme1.cpp new file mode 100644 index 000000000..2ca10c166 --- /dev/null +++ b/src/pk_pad/eme1/eme1.cpp @@ -0,0 +1,95 @@ +/************************************************* +* EME1 Source File * +* (C) 1999-2007 Jack Lloyd * +*************************************************/ + +#include <botan/eme1.h> +#include <botan/lookup.h> +#include <memory> + +namespace Botan { + +/************************************************* +* EME1 Pad Operation * +*************************************************/ +SecureVector<byte> EME1::pad(const byte in[], u32bit in_length, + u32bit key_length, + RandomNumberGenerator& rng) const + { + key_length /= 8; + + if(in_length > key_length - 2*HASH_LENGTH - 1) + throw Exception("EME1: Input is too large"); + + SecureVector<byte> out(key_length); + + out.clear(); + + rng.randomize(out, HASH_LENGTH); + + out.copy(HASH_LENGTH, Phash, Phash.size()); + out[out.size() - in_length - 1] = 0x01; + out.copy(out.size() - in_length, in, in_length); + mgf->mask(out, HASH_LENGTH, out + HASH_LENGTH, out.size() - HASH_LENGTH); + mgf->mask(out + HASH_LENGTH, out.size() - HASH_LENGTH, out, HASH_LENGTH); + + return out; + } + +/************************************************* +* EME1 Unpad Operation * +*************************************************/ +SecureVector<byte> EME1::unpad(const byte in[], u32bit in_length, + u32bit key_length) const + { + key_length /= 8; + if(in_length > key_length) + throw Decoding_Error("Invalid EME1 encoding"); + + SecureVector<byte> tmp(key_length); + tmp.copy(key_length - in_length, in, in_length); + + mgf->mask(tmp + HASH_LENGTH, tmp.size() - HASH_LENGTH, tmp, HASH_LENGTH); + mgf->mask(tmp, HASH_LENGTH, tmp + HASH_LENGTH, tmp.size() - HASH_LENGTH); + + for(u32bit j = 0; j != Phash.size(); ++j) + if(tmp[j+HASH_LENGTH] != Phash[j]) + throw Decoding_Error("Invalid EME1 encoding"); + + for(u32bit j = HASH_LENGTH + Phash.size(); j != tmp.size(); ++j) + { + if(tmp[j] && tmp[j] != 0x01) + throw Decoding_Error("Invalid EME1 encoding"); + if(tmp[j] && tmp[j] == 0x01) + { + SecureVector<byte> retval(tmp + j + 1, tmp.size() - j - 1); + return retval; + } + } + throw Decoding_Error("Invalid EME1 encoding"); + } + +/************************************************* +* Return the max input size for a given key size * +*************************************************/ +u32bit EME1::maximum_input_size(u32bit keybits) const + { + if(keybits / 8 > 2*HASH_LENGTH + 1) + return ((keybits / 8) - 2*HASH_LENGTH - 1); + else + return 0; + } + +/************************************************* +* EME1 Constructor * +*************************************************/ +EME1::EME1(const std::string& hash_name, const std::string& mgf_name, + const std::string& P) : + HASH_LENGTH(output_length_of(hash_name)) + { + mgf = get_mgf(mgf_name + "(" + hash_name + ")"); + std::auto_ptr<HashFunction> hash(get_hash(hash_name)); + Phash = hash->process(P); + } + +} diff --git a/src/pk_pad/eme1/eme1.h b/src/pk_pad/eme1/eme1.h new file mode 100644 index 000000000..2a0ac92c4 --- /dev/null +++ b/src/pk_pad/eme1/eme1.h @@ -0,0 +1,35 @@ +/************************************************* +* EME1 Header File * +* (C) 1999-2007 Jack Lloyd * +*************************************************/ + +#ifndef BOTAN_EME1_H__ +#define BOTAN_EME1_H__ + +#include <botan/pk_util.h> + +namespace Botan { + +/************************************************* +* EME1 * +*************************************************/ +class BOTAN_DLL EME1 : public EME + { + public: + u32bit maximum_input_size(u32bit) const; + + EME1(const std::string&, const std::string&, const std::string& = ""); + ~EME1() { delete mgf; } + private: + SecureVector<byte> pad(const byte[], u32bit, u32bit, + RandomNumberGenerator&) const; + SecureVector<byte> unpad(const byte[], u32bit, u32bit) const; + + const u32bit HASH_LENGTH; + SecureVector<byte> Phash; + MGF* mgf; + }; + +} + +#endif diff --git a/src/pk_pad/eme1/modinfo.txt b/src/pk_pad/eme1/modinfo.txt new file mode 100644 index 000000000..5383d59b6 --- /dev/null +++ b/src/pk_pad/eme1/modinfo.txt @@ -0,0 +1,10 @@ +realname "EME1" + +define EME1 + +load_on auto + +<add> +eme1.h +eme1.cpp +</add> |