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[zpackage] / libtomcrypt / src / modes / cbc / cbc_encrypt.c
diff --git a/libtomcrypt/src/modes/cbc/cbc_encrypt.c b/libtomcrypt/src/modes/cbc/cbc_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.
+ */
+#include "tomcrypt.h"
+
+/**
+   @file cbc_encrypt.c
+   CBC implementation, encrypt block, Tom St Denis
+*/
+
+
+#ifdef LTC_CBC_MODE
+
+/**
+  CBC encrypt
+  @param pt     Plaintext
+  @param ct     [out] Ciphertext
+  @param len    The number of bytes to process (must be multiple of block length)
+  @param cbc    CBC state
+  @return CRYPT_OK if successful
+*/
+int cbc_encrypt(const unsigned char *pt, unsigned char *ct, unsigned long len, symmetric_CBC *cbc)
+{
+   int x, err;
+
+   LTC_ARGCHK(pt != NULL);
+   LTC_ARGCHK(ct != NULL);
+   LTC_ARGCHK(cbc != NULL);
+
+   if ((err = cipher_is_valid(cbc->cipher)) != CRYPT_OK) {
+       return err;
+   }
+
+   /* is blocklen valid? */
+   if (cbc->blocklen < 1 || cbc->blocklen > (int)sizeof(cbc->IV)) {
+      return CRYPT_INVALID_ARG;
+   }
+
+   if (len % cbc->blocklen) {
+      return CRYPT_INVALID_ARG;
+   }
+#ifdef LTC_FAST
+   if (cbc->blocklen % sizeof(LTC_FAST_TYPE)) {
+      return CRYPT_INVALID_ARG;
+   }
+#endif
+
+   if (cipher_descriptor[cbc->cipher].accel_cbc_encrypt != NULL) {
+      return cipher_descriptor[cbc->cipher].accel_cbc_encrypt(pt, ct, len / cbc->blocklen, cbc->IV, &cbc->key);
+   } else {
+      while (len) {
+         /* xor IV against plaintext */
+         #if defined(LTC_FAST)
+         for (x = 0; x < cbc->blocklen; x += sizeof(LTC_FAST_TYPE)) {
+            *(LTC_FAST_TYPE_PTR_CAST((unsigned char *)cbc->IV + x)) ^= *(LTC_FAST_TYPE_PTR_CAST((unsigned char *)pt + x));
+         }
+    #else
+         for (x = 0; x < cbc->blocklen; x++) {
+            cbc->IV[x] ^= pt[x];
+         }
+    #endif
+
+         /* encrypt */
+         if ((err = cipher_descriptor[cbc->cipher].ecb_encrypt(cbc->IV, ct, &cbc->key)) != CRYPT_OK) {
+            return err;
+         }
+
+         /* store IV [ciphertext] for a future block */
+         #if defined(LTC_FAST)
+         for (x = 0; x < cbc->blocklen; x += sizeof(LTC_FAST_TYPE)) {
+            *(LTC_FAST_TYPE_PTR_CAST((unsigned char *)cbc->IV + x)) = *(LTC_FAST_TYPE_PTR_CAST((unsigned char *)ct + x));
+         }
+    #else
+         for (x = 0; x < cbc->blocklen; x++) {
+            cbc->IV[x] = ct[x];
+         }
+    #endif
+
+         ct  += cbc->blocklen;
+         pt  += cbc->blocklen;
+         len -= cbc->blocklen;
+      }
+   }
+   return CRYPT_OK;
+}
+
+#endif
+
+/* ref:         $Format:%D$ */
+/* git commit:  $Format:%H$ */
+/* commit time: $Format:%ai$ */