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Diffstat (limited to 'libtomcrypt/src/encauth/gcm/gcm_memory.c')
-rw-r--r--libtomcrypt/src/encauth/gcm/gcm_memory.c109
1 files changed, 109 insertions, 0 deletions
diff --git a/libtomcrypt/src/encauth/gcm/gcm_memory.c b/libtomcrypt/src/encauth/gcm/gcm_memory.c
new file mode 100644
index 0000000..ddec010
--- /dev/null
+++ b/libtomcrypt/src/encauth/gcm/gcm_memory.c
@@ -0,0 +1,109 @@
+/* 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
+ */
+
+/**
+ @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)
+{
+ void *orig;
+ gcm_state *gcm;
+ int err;
+
+ if ((err = cipher_is_valid(cipher)) != CRYPT_OK) {
+ return err;
+ }
+
+ if (cipher_descriptor[cipher].accel_gcm_memory != NULL) {
+ return
+ cipher_descriptor[cipher].accel_gcm_memory
+ (key, keylen,
+ IV, IVlen,
+ adata, adatalen,
+ pt, ptlen,
+ ct,
+ tag, taglen,
+ direction);
+ }
+
+
+
+#ifndef GCM_TABLES_SSE2
+ orig = gcm = XMALLOC(sizeof(*gcm));
+#else
+ orig = gcm = XMALLOC(sizeof(*gcm) + 16);
+#endif
+ if (gcm == NULL) {
+ return CRYPT_MEM;
+ }
+
+ /* Force GCM to be on a multiple of 16 so we can use 128-bit aligned operations
+ * note that we only modify gcm and keep orig intact. This code is not portable
+ * but again it's only for SSE2 anyways, so who cares?
+ */
+#ifdef GCM_TABLES_SSE2
+ if ((unsigned long)gcm & 15) {
+ gcm = (gcm_state *)((unsigned long)gcm + (16 - ((unsigned long)gcm & 15)));
+ }
+#endif
+
+ 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(orig);
+ return err;
+}
+#endif
+
+
+/* $Source: /cvs/libtom/libtomcrypt/src/encauth/gcm/gcm_memory.c,v $ */
+/* $Revision: 1.23 $ */
+/* $Date: 2006/09/07 10:00:57 $ */