diff options
Diffstat (limited to 'libtomcrypt/src/mac/f9/f9_done.c')
-rw-r--r-- | libtomcrypt/src/mac/f9/f9_done.c | 77 |
1 files changed, 77 insertions, 0 deletions
diff --git a/libtomcrypt/src/mac/f9/f9_done.c b/libtomcrypt/src/mac/f9/f9_done.c new file mode 100644 index 0000000..1794ecc --- /dev/null +++ b/libtomcrypt/src/mac/f9/f9_done.c @@ -0,0 +1,77 @@ +/* LibTomCrypt, modular cryptographic library -- Tom St Denis + * + * LibTomCrypt is a library that provides various cryptographic + * algorithms in a highly modular and flexible manner. + * + * The library is free for all purposes without any express + * guarantee it works. + * + * Tom St Denis, tomstdenis@gmail.com, http://libtomcrypt.com + */ +#include "tomcrypt.h" + +/** + @file f9_done.c + f9 Support, terminate the state +*/ + +#ifdef LTC_F9_MODE + +/** Terminate the f9-MAC state + @param f9 f9 state to terminate + @param out [out] Destination for the MAC tag + @param outlen [in/out] Destination size and final tag size + Return CRYPT_OK on success +*/ +int f9_done(f9_state *f9, unsigned char *out, unsigned long *outlen) +{ + int err, x; + LTC_ARGCHK(f9 != NULL); + LTC_ARGCHK(out != NULL); + + /* check structure */ + if ((err = cipher_is_valid(f9->cipher)) != CRYPT_OK) { + return err; + } + + if ((f9->blocksize > cipher_descriptor[f9->cipher].block_length) || (f9->blocksize < 0) || + (f9->buflen > f9->blocksize) || (f9->buflen < 0)) { + return CRYPT_INVALID_ARG; + } + + if (f9->buflen != 0) { + /* encrypt */ + cipher_descriptor[f9->cipher].ecb_encrypt(f9->IV, f9->IV, &f9->key); + f9->buflen = 0; + for (x = 0; x < f9->blocksize; x++) { + f9->ACC[x] ^= f9->IV[x]; + } + } + + /* schedule modified key */ + if ((err = cipher_descriptor[f9->cipher].setup(f9->akey, f9->keylen, 0, &f9->key)) != CRYPT_OK) { + return err; + } + + /* encrypt the ACC */ + cipher_descriptor[f9->cipher].ecb_encrypt(f9->ACC, f9->ACC, &f9->key); + cipher_descriptor[f9->cipher].done(&f9->key); + + /* extract tag */ + for (x = 0; x < f9->blocksize && (unsigned long)x < *outlen; x++) { + out[x] = f9->ACC[x]; + } + *outlen = x; + +#ifdef LTC_CLEAN_STACK + zeromem(f9, sizeof(*f9)); +#endif + return CRYPT_OK; +} + +#endif + +/* $Source: /cvs/libtom/libtomcrypt/src/mac/f9/f9_done.c,v $ */ +/* $Revision: 1.5 $ */ +/* $Date: 2006/11/09 01:53:32 $ */ + |