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author | lloyd <[email protected]> | 2014-01-10 03:41:59 +0000 |
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committer | lloyd <[email protected]> | 2014-01-10 03:41:59 +0000 |
commit | 6894dca64c04936d07048c0e8cbf7e25858548c3 (patch) | |
tree | 5d572bfde9fe667dab14e3f04b5285a85d8acd95 /src/lib/algo_base/key_spec.h | |
parent | 9efa3be92442afb3d0b69890a36c7f122df18eda (diff) |
Move lib into src
Diffstat (limited to 'src/lib/algo_base/key_spec.h')
-rw-r--r-- | src/lib/algo_base/key_spec.h | 95 |
1 files changed, 95 insertions, 0 deletions
diff --git a/src/lib/algo_base/key_spec.h b/src/lib/algo_base/key_spec.h new file mode 100644 index 000000000..15881c1a6 --- /dev/null +++ b/src/lib/algo_base/key_spec.h @@ -0,0 +1,95 @@ +/* +* Symmetric Key Length Specification +* (C) 2010 Jack Lloyd +* +* Distributed under the terms of the Botan license +*/ + +#ifndef BOTAN_KEY_LEN_SPECIFICATION_H__ +#define BOTAN_KEY_LEN_SPECIFICATION_H__ + +#include <botan/types.h> + +namespace Botan { + +/** +* Represents the length requirements on an algorithm key +*/ +class BOTAN_DLL Key_Length_Specification + { + public: + /** + * Constructor for fixed length keys + * @param keylen the supported key length + */ + Key_Length_Specification(size_t keylen) : + min_keylen(keylen), + max_keylen(keylen), + keylen_mod(1) + { + } + + /** + * Constructor for variable length keys + * @param min_k the smallest supported key length + * @param max_k the largest supported key length + * @param k_mod the number of bytes the key must be a multiple of + */ + Key_Length_Specification(size_t min_k, + size_t max_k, + size_t k_mod = 1) : + min_keylen(min_k), + max_keylen(max_k ? max_k : min_k), + keylen_mod(k_mod) + { + } + + /** + * @param length is a key length in bytes + * @return true iff this length is a valid length for this algo + */ + bool valid_keylength(size_t length) const + { + return ((length >= min_keylen) && + (length <= max_keylen) && + (length % keylen_mod == 0)); + } + + /** + * @return minimum key length in bytes + */ + size_t minimum_keylength() const + { + return min_keylen; + } + + /** + * @return maximum key length in bytes + */ + size_t maximum_keylength() const + { + return max_keylen; + } + + /** + * @return key length multiple in bytes + */ + size_t keylength_multiple() const + { + return keylen_mod; + } + + Key_Length_Specification multiple(size_t n) const + { + return Key_Length_Specification(n * min_keylen, + n * max_keylen, + n * keylen_mod); + } + + private: + size_t min_keylen, max_keylen, keylen_mod; + }; + +} + +#endif |