X-Git-Url: https://pd.if.org/git/?a=blobdiff_plain;f=libtomcrypt%2Fsrc%2Fmodes%2Fcfb%2Fcfb_start.c;fp=libtomcrypt%2Fsrc%2Fmodes%2Fcfb%2Fcfb_start.c;h=e49b119b6021041330022c9a557d5692218c2e13;hb=66bc25938679f1d6a1d1200f329093d82a5e99b4;hp=0000000000000000000000000000000000000000;hpb=a52ee0733f420ca20224049260d6fc5cf7d8f621;p=zpackage diff --git a/libtomcrypt/src/modes/cfb/cfb_start.c b/libtomcrypt/src/modes/cfb/cfb_start.c new file mode 100644 index 0000000..e49b119 --- /dev/null +++ b/libtomcrypt/src/modes/cfb/cfb_start.c @@ -0,0 +1,63 @@ +/* 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. + */ +#include "tomcrypt.h" + +/** + @file cfb_start.c + CFB implementation, start chain, Tom St Denis +*/ + + +#ifdef LTC_CFB_MODE + +/** + Initialize a CFB context + @param cipher The index of the cipher desired + @param IV The initialization vector + @param key The secret key + @param keylen The length of the secret key (octets) + @param num_rounds Number of rounds in the cipher desired (0 for default) + @param cfb The CFB state to initialize + @return CRYPT_OK if successful +*/ +int cfb_start(int cipher, const unsigned char *IV, const unsigned char *key, + int keylen, int num_rounds, symmetric_CFB *cfb) +{ + int x, err; + + LTC_ARGCHK(IV != NULL); + LTC_ARGCHK(key != NULL); + LTC_ARGCHK(cfb != NULL); + + if ((err = cipher_is_valid(cipher)) != CRYPT_OK) { + return err; + } + + + /* copy data */ + cfb->cipher = cipher; + cfb->blocklen = cipher_descriptor[cipher].block_length; + for (x = 0; x < cfb->blocklen; x++) + cfb->IV[x] = IV[x]; + + /* init the cipher */ + if ((err = cipher_descriptor[cipher].setup(key, keylen, num_rounds, &cfb->key)) != CRYPT_OK) { + return err; + } + + /* encrypt the IV */ + cfb->padlen = 0; + return cipher_descriptor[cfb->cipher].ecb_encrypt(cfb->IV, cfb->IV, &cfb->key); +} + +#endif + +/* ref: $Format:%D$ */ +/* git commit: $Format:%H$ */ +/* commit time: $Format:%ai$ */