diff options
Diffstat (limited to 'src/encauth/gcm/gcm_memory.c')
-rw-r--r-- | src/encauth/gcm/gcm_memory.c | 93 |
1 files changed, 93 insertions, 0 deletions
diff --git a/src/encauth/gcm/gcm_memory.c b/src/encauth/gcm/gcm_memory.c new file mode 100644 index 0000000..ee10d3f --- /dev/null +++ b/src/encauth/gcm/gcm_memory.c @@ -0,0 +1,93 @@ +/* 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.org + */ + +/** + @file gcm_memory.c + GCM implementation, process a packet, by Tom St Denis +*/ +#include "tomcrypt.h" + +#ifdef GCM_MODE + +/** + Process an entire GCM packet in one call. + @param cipher Index of cipher to use + @param key The secret key + @param keylen The length of the secret key + @param IV The initial vector + @param IVlen The length of the initial vector + @param adata The additional authentication data (header) + @param adatalen The length of the adata + @param pt The plaintext + @param ptlen The length of the plaintext (ciphertext length is the same) + @param ct The ciphertext + @param tag [out] The MAC tag + @param taglen [in/out] The MAC tag length + @param direction Encrypt or Decrypt mode (GCM_ENCRYPT or GCM_DECRYPT) + @return CRYPT_OK on success + */ +int gcm_memory( int cipher, + const unsigned char *key, unsigned long keylen, + const unsigned char *IV, unsigned long IVlen, + const unsigned char *adata, unsigned long adatalen, + unsigned char *pt, unsigned long ptlen, + unsigned char *ct, + unsigned char *tag, unsigned long *taglen, + int direction) +{ + gcm_state *gcm; + int err; + + if ((err = cipher_is_valid(cipher)) != CRYPT_OK) { + return err; + } + + if (cipher_descriptor[cipher].accel_gcm_memory != NULL) { + cipher_descriptor[cipher].accel_gcm_memory + (key, keylen, + IV, IVlen, + adata, adatalen, + pt, ptlen, + ct, + tag, taglen, + direction); + return CRYPT_OK; + } + + + gcm = XMALLOC(sizeof(*gcm)); + if (gcm == NULL) { + return CRYPT_MEM; + } + + if ((err = gcm_init(gcm, cipher, key, keylen)) != CRYPT_OK) { + goto LTC_ERR; + } + if ((err = gcm_add_iv(gcm, IV, IVlen)) != CRYPT_OK) { + goto LTC_ERR; + } + if ((err = gcm_add_aad(gcm, adata, adatalen)) != CRYPT_OK) { + goto LTC_ERR; + } + if ((err = gcm_process(gcm, pt, ptlen, ct, direction)) != CRYPT_OK) { + goto LTC_ERR; + } + err = gcm_done(gcm, tag, taglen); +LTC_ERR: + XFREE(gcm); + return err; +} +#endif + + +/* $Source: /cvs/libtom/libtomcrypt/src/encauth/gcm/gcm_memory.c,v $ */ +/* $Revision: 1.19 $ */ +/* $Date: 2005/05/05 14:35:58 $ */ |