X-Git-Url: https://git.cryptolib.org/?a=blobdiff_plain;f=cast5.h;h=aa81ca19a8fb0f5308ccd440363796f937c87938;hb=a15d02c94b1ce1fc9861e654e96e0ee369fe08e9;hp=717c5d7b7a9e1ac7059e115d1b8016581f7bbff0;hpb=2e7bb1f5e50ed450e1b3ab16283783ff64b66218;p=avr-crypto-lib.git diff --git a/cast5.h b/cast5.h index 717c5d7..aa81ca1 100644 --- a/cast5.h +++ b/cast5.h @@ -24,6 +24,16 @@ * Description: Implementation of the CAST5 (aka CAST-128) cipher algorithm as described in RFC 2144 * */ + +/** + * \file cast5.h + * \author Daniel Otte + * \date 2006-07-26 + * \license GPL + * \brief Implementation of the CAST5 (aka CAST-128) cipher algorithm as described in RFC 2144 + * + */ + #ifndef CAST5_H_ #define CAST5_H_ @@ -40,7 +50,13 @@ #endif #endif - +/** \typedef cast5_ctx_t + * \brief CAST-5 context + * + * A variable of this type may hold a keyschedule for the CAST-5 cipher. + * This context is regulary generated by the + * cast5_init(uint8_t* key, uint8_t keylength_b, cast5_ctx_t* s) funtion. + */ typedef struct cast5_ctx_st{ uint32_t mask[16]; uint8_t rotl[8]; /* 4 bit from every rotation key is stored here */ @@ -48,9 +64,39 @@ typedef struct cast5_ctx_st{ bool shortkey; } cast5_ctx_t; -void cast5_init(uint8_t* key, uint8_t keylength_b, cast5_ctx_t* s); -void cast5_enc(void* block, cast5_ctx_t *s); -void cast5_dec(void* block, cast5_ctx_t *s); + +/** \fn void cast5_init(void* key, uint8_t keylength_b, cast5_ctx_t* s); + * \brief generate keyschedule/contex for CAST-5 + * + * This function generates the keyschedule from the supplied key for the + * CAST-5 cipher and stores it in a supplied ::cast5_ctx_t context. + * \param key pointer to the key + * \param keylength_b length of the key in bits (maximum 128 bits) + * \param s pointer to the context + */ +void cast5_init(void* key, uint8_t keylength_b, cast5_ctx_t* s); + +/** \fn void cast5_enc(void* block, const cast5_ctx_t *s); + * \brief encrypt a block with the CAST-5 algorithm + * + * This function encrypts a block of 64 bits (8 bytes) with the CAST-5 algorithm. + * It uses a keyschedule as generated by the + * cast5_init(void* key, uint8_t keylength_b, cast5_ctx_t* s) function. + * \param block pointer to the block which gets encrypted + * \param s pointer to the keyschedule/context + */ +void cast5_enc(void* block, const cast5_ctx_t *s); + +/** \fn void cast5_dec(void* block, const cast5_ctx_t *s); + * \brief decrypt a block with the CAST-5 algorithm + * + * This function decrypts a block of 64 bits (8 bytes) with the CAST-5 algorithm. + * It uses a keyschedule as generated by the + * cast5_init(void* key, uint8_t keylength_b, cast5_ctx_t* s) function. + * \param block pointer to the block which gets decrypted + * \param s pointer to the keyschedule/context + */ +void cast5_dec(void* block, const cast5_ctx_t *s);