commit files needed for zpm-fetchurl

[zpackage] / libtomcrypt / src / encauth / ocb / ocb_encrypt.c

diff --git a/libtomcrypt/src/encauth/ocb/ocb_encrypt.c b/libtomcrypt/src/encauth/ocb/ocb_encrypt.c
new file mode 100644 (file)
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+++ b/libtomcrypt/src/encauth/ocb/ocb_encrypt.c
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+/* 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.
+ */
+
+/**
+   @file ocb_encrypt.c
+   OCB implementation, encrypt data, by Tom St Denis
+*/
+#include "tomcrypt.h"
+
+#ifdef LTC_OCB_MODE
+
+/**
+   Encrypt a block of data with OCB.
+   @param ocb     The OCB state
+   @param pt      The plaintext (length of the block size of the block cipher)
+   @param ct      [out] The ciphertext (same size as the pt)
+   @return CRYPT_OK if successful
+*/
+int ocb_encrypt(ocb_state *ocb, const unsigned char *pt, unsigned char *ct)
+{
+   unsigned char Z[MAXBLOCKSIZE], tmp[MAXBLOCKSIZE];
+   int err, x;
+
+   LTC_ARGCHK(ocb != NULL);
+   LTC_ARGCHK(pt  != NULL);
+   LTC_ARGCHK(ct  != NULL);
+   if ((err = cipher_is_valid(ocb->cipher)) != CRYPT_OK) {
+      return err;
+   }
+   if (ocb->block_len != cipher_descriptor[ocb->cipher].block_length) {
+      return CRYPT_INVALID_ARG;
+   }
+
+   /* compute checksum */
+   for (x = 0; x < ocb->block_len; x++) {
+       ocb->checksum[x] ^= pt[x];
+   }
+
+   /* Get Z[i] value */
+   ocb_shift_xor(ocb, Z);
+
+   /* xor pt in, encrypt, xor Z out */
+   for (x = 0; x < ocb->block_len; x++) {
+       tmp[x] = pt[x] ^ Z[x];
+   }
+   if ((err = cipher_descriptor[ocb->cipher].ecb_encrypt(tmp, ct, &ocb->key)) != CRYPT_OK) {
+      return err;
+   }
+   for (x = 0; x < ocb->block_len; x++) {
+       ct[x] ^= Z[x];
+   }
+
+#ifdef LTC_CLEAN_STACK
+   zeromem(Z, sizeof(Z));
+   zeromem(tmp, sizeof(tmp));
+#endif
+   return CRYPT_OK;
+}
+
+#endif
+
+/* ref:         $Format:%D$ */
+/* git commit:  $Format:%H$ */
+/* commit time: $Format:%ai$ */