X-Git-Url: http://git.silcnet.org/gitweb/?a=blobdiff_plain;f=lib%2Fsilccrypt%2Fsilccipher.h;h=a0503c899105d6ffa06c1f3c72fde2f8e332a2af;hb=e7b6c157b80152bf9fb9266e6bdd93f9fb0db776;hp=3afede61ea8c486e5a4175c601005046d3149d87;hpb=8fd8212bcd16f2b53fbedff2a9b9a4e8c15b9695;p=silc.git diff --git a/lib/silccrypt/silccipher.h b/lib/silccrypt/silccipher.h index 3afede61..a0503c89 100644 --- a/lib/silccrypt/silccipher.h +++ b/lib/silccrypt/silccipher.h @@ -17,9 +17,6 @@ */ -#ifndef SILCCIPHER_H -#define SILCCIPHER_H - /****h* silccrypt/SILC Cipher Interface * * DESCRIPTION @@ -30,11 +27,17 @@ * ***/ +#ifndef SILCCIPHER_H +#define SILCCIPHER_H + +/* Forward declarations */ +typedef struct SilcCipherObjectStruct SilcCipherObject; + /****s* silccrypt/SilcCipherAPI/SilcCipher * * NAME * - * typedef struct { ... } SilcCipher; + * typedef struct SilcCipherStruct *SilcCipher; * * DESCRIPTION * @@ -46,70 +49,6 @@ ***/ typedef struct SilcCipherStruct *SilcCipher; -/* The default SILC Cipher object to represent any cipher in SILC. */ -typedef struct { - char *name; - SilcBool (*set_key)(void *, const unsigned char *, SilcUInt32, SilcBool); - void (*set_iv)(void *, const unsigned char *); - SilcBool (*encrypt)(void *, const unsigned char *, unsigned char *, - SilcUInt32, unsigned char *); - SilcBool (*decrypt)(void *, const unsigned char *, unsigned char *, - SilcUInt32, unsigned char *); - SilcUInt32 (*context_len)(); - unsigned int key_len : 10; - unsigned int block_len : 8; - unsigned int iv_len : 8; - unsigned int mode : 6; -} SilcCipherObject; - -#define SILC_CIPHER_MAX_IV_SIZE 16 - -/* Marks for all ciphers in silc. This can be used in silc_cipher_unregister - to unregister all ciphers at once. */ -#define SILC_ALL_CIPHERS ((SilcCipherObject *)1) - -/* Static list of ciphers for silc_cipher_register_default(). */ -extern DLLAPI const SilcCipherObject silc_default_ciphers[]; - -/* Default cipher in the SILC protocol */ -#define SILC_DEFAULT_CIPHER "aes-256-cbc" - -/* Macros */ - -/* Function names in SILC Crypto modules. The name of the cipher - is appended into these names and used to the get correct symbol out - of the module. All SILC Crypto API compliant modules must support - these function names (use macros below to assure this). */ -#define SILC_CIPHER_SIM_SET_KEY "set_key" -#define SILC_CIPHER_SIM_ENCRYPT "encrypt" -#define SILC_CIPHER_SIM_DECRYPT "decrypt" -#define SILC_CIPHER_SIM_CONTEXT_LEN "context_len" - -/* These macros can be used to implement the SILC Crypto API and to avoid - errors in the API these macros should be used always. */ -#define SILC_CIPHER_API_SET_KEY(cipher) \ -SilcBool silc_##cipher##_set_key(void *context, \ - const unsigned char *key, \ - SilcUInt32 keylen, \ - SilcBool encryption) -#define SILC_CIPHER_API_SET_IV(cipher) \ -void silc_##cipher##_set_iv(void *context, \ - const unsigned char *iv) -#define SILC_CIPHER_API_ENCRYPT(cipher) \ -SilcBool silc_##cipher##_encrypt(void *context, \ - const unsigned char *src, \ - unsigned char *dst, \ - SilcUInt32 len, \ - unsigned char *iv) -#define SILC_CIPHER_API_DECRYPT(cipher) \ -SilcBool silc_##cipher##_decrypt(void *context, \ - const unsigned char *src, \ - unsigned char *dst, \ - SilcUInt32 len, \ - unsigned char *iv) -#define SILC_CIPHER_API_CONTEXT_LEN(cipher) \ -SilcUInt32 silc_##cipher##_context_len() - /****d* silccrypt/SilcCipherAPI/SilcCipherMode * * NAME @@ -118,7 +57,48 @@ SilcUInt32 silc_##cipher##_context_len() * * DESCRIPTION * - * Cipher modes. + * Cipher modes. Notes about cipher modes and implementation: + * + * SILC_CIPHER_MODE_CBC + * + * The Cipher-block Chaining mode. The CBC is mode is a standard CBC + * mode. The plaintext length must be multiple by the cipher block size. + * If it isn't the plaintext must be padded. + * + * SILC_CIPHER_MODE_CTR + * + * The Counter mode. The CTR is normal counter mode. The CTR mode does + * not require the plaintext length to be multiple by the cipher block + * size. If the last plaintext block is shorter the remaining bits of + * the key stream are used next time silc_cipher_encrypt is called. If + * silc_cipher_set_iv is called it will reset the counter for a new block + * (discarding any remaining bits from previous key stream). The counter + * mode expects MSB first ordered counter. Note also, the counter is + * incremented when silc_cipher_encrypt is called for the first time, + * before encrypting. + * + * SILC_CIPHER_MODE_CFB + * + * The Cipher Feedback mode. The CFB mode is normal cipher feedback mode. + * The CFB mode does not require the plaintext length to be multiple by + * the cipher block size. If the last plaintext block is shorter the + * remaining bits of the stream are used next time silc_cipher_encrypt is + * called. If silc_cipher_set_iv is called it will reset the feedback + * for a new block (discarding any remaining bits from previous stream). + * + * SILC_CIPHER_MODE_OFB + * + * The Output Feedback mode. + * + * SILC_CIPHER_MODE_ECB + * + * The Electronic Codebook mode. This mode does not provide sufficient + * security and should not be used. + * + * Each mode modifies the IV (initialization vector) of the cipher when + * silc_cipher_encrypt or silc_cipher_decrypt is called. The IV may be + * set/reset by calling silc_cipher_set_iv and the current IV can be + * retrieved by calling silc_cipher_get_iv. * * SOURCE */ @@ -131,6 +111,18 @@ typedef enum { } SilcCipherMode; /***/ +#define SILC_CIPHER_MAX_IV_SIZE 16 /* Maximum IV size */ +#define SILC_DEFAULT_CIPHER "aes-256-cbc" /* Default cipher */ + +/* Marks for all ciphers in silc. This can be used in silc_cipher_unregister + to unregister all ciphers at once. */ +#define SILC_ALL_CIPHERS ((SilcCipherObject *)1) + +#include "silccipher_i.h" + +/* Static list of ciphers for silc_cipher_register_default(). */ +extern DLLAPI const SilcCipherObject silc_default_ciphers[]; + /* Prototypes */ /****f* silccrypt/SilcCipherAPI/silc_cipher_register @@ -194,7 +186,7 @@ SilcBool silc_cipher_unregister_all(void); * * SYNOPSIS * - * SilcBool silc_cipher_alloc(const unsigned char *name, + * SilcBool silc_cipher_alloc(const char *name, * SilcCipher *new_cipher); * * DESCRIPTION @@ -218,19 +210,8 @@ SilcBool silc_cipher_unregister_all(void); * * Notes about modes: * - * The CTR is normal counter mode. The CTR mode does not require the - * plaintext length to be multiple by the cipher block size. If the last - * plaintext block is shorter the remaining bits of the key stream are - * used next time silc_cipher_encrypt is called. If silc_cipher_set_iv - * is called it will reset the counter for a new block (discarding any - * remaining bits from previous key stream). - * - * The CBC is mode is a standard CBC mode. The plaintext length must be - * multiple by the cipher block size. If it isn't the plaintext must be - * padded. - * ***/ -SilcBool silc_cipher_alloc(const unsigned char *name, SilcCipher *new_cipher); +SilcBool silc_cipher_alloc(const char *name, SilcCipher *new_cipher); /****f* silccrypt/SilcCipherAPI/silc_cipher_free * @@ -249,27 +230,31 @@ void silc_cipher_free(SilcCipher cipher); * * SYNOPSIS * - * SilcBool silc_cipher_is_supported(const unsigned char *name); + * SilcBool silc_cipher_is_supported(const char *name); * * DESCRIPTION * * Returns TRUE if cipher `name' is supported. * ***/ -SilcBool silc_cipher_is_supported(const unsigned char *name); +SilcBool silc_cipher_is_supported(const char *name); /****f* silccrypt/SilcCipherAPI/silc_cipher_get_supported * * SYNOPSIS * - * char *silc_cipher_get_supported(void); + * char *silc_cipher_get_supported(SilcBool only_registered); * * DESCRIPTION * - * Returns comma separated list of supported ciphers. + * Returns comma separated list of supported ciphers. If `only_registered' + * is TRUE only ciphers explicitly registered with silc_cipher_register + * are returned. If FALSE, then all registered and default builtin + * ciphers are returned. However, if there are no registered ciphers + * and `only_registered' is TRUE, the builtin ciphers are returned. * ***/ -char *silc_cipher_get_supported(void); +char *silc_cipher_get_supported(SilcBool only_registered); /****f* silccrypt/SilcCipherAPI/silc_cipher_encrypt * @@ -336,13 +321,16 @@ SilcBool silc_cipher_set_key(SilcCipher cipher, const unsigned char *key, * * DESCRIPTION * - * Sets the IV (initial vector) for the cipher. The `iv' must be + * Sets the IV (initialization vector) for the cipher. The `iv' must be * the size of the block size of the cipher. If `iv' is NULL this * does not do anything. * * If the encryption mode is CTR (Counter mode) this also resets the * the counter for a new block. This is done also if `iv' is NULL. * + * If the encryption mode is CFB (cipher feedback) this also resets the + * the feedback stream for a new block. This is done also if `iv' is NULL. + * ***/ void silc_cipher_set_iv(SilcCipher cipher, const unsigned char *iv);