1 files changed, 83 insertions, 0 deletions
diff --git a/libtomcrypt/src/mac/omac/omac_file.c b/libtomcrypt/src/mac/omac/omac_file.c
new file mode 100644
index 0000000..7117ae3
--- /dev/null
+++ b/libtomcrypt/src/mac/omac/omac_file.c
@@ -0,0 +1,83 @@
+/* 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
+ */
+#include "tomcrypt.h"
+
+/** 
+  @file omac_file.c
+  OMAC1 support, process a file, Tom St Denis
+*/
+
+#ifdef LTC_OMAC
+
+/**
+   OMAC a file
+   @param cipher   The index of the cipher desired
+   @param key      The secret key
+   @param keylen   The length of the secret key (octets)
+   @param filename The name of the file you wish to OMAC
+   @param out      [out] Where the authentication tag is to be stored
+   @param outlen   [in/out] The max size and resulting size of the authentication tag
+   @return CRYPT_OK if successful, CRYPT_NOP if file support has been disabled
+*/
+int omac_file(int cipher, 
+              const unsigned char *key, unsigned long keylen,
+              const char *filename, 
+                    unsigned char *out, unsigned long *outlen)
+{
+#ifdef LTC_NO_FILE
+   return CRYPT_NOP;
+#else
+   int err, x;
+   omac_state omac;
+   FILE *in;
+   unsigned char buf[512];
+
+   LTC_ARGCHK(key      != NULL);
+   LTC_ARGCHK(filename != NULL);
+   LTC_ARGCHK(out      != NULL);
+   LTC_ARGCHK(outlen   != NULL);
+
+   in = fopen(filename, "rb");
+   if (in == NULL) {
+      return CRYPT_FILE_NOTFOUND;
+   }
+
+   if ((err = omac_init(&omac, cipher, key, keylen)) != CRYPT_OK) {
+      fclose(in);
+      return err;
+   }
+
+   do {
+      x = fread(buf, 1, sizeof(buf), in);
+      if ((err = omac_process(&omac, buf, x)) != CRYPT_OK) {
+         fclose(in);
+         return err;
+      }
+   } while (x == sizeof(buf));
+   fclose(in);
+
+   if ((err = omac_done(&omac, out, outlen)) != CRYPT_OK) {
+      return err;
+   }
+
+#ifdef LTC_CLEAN_STACK
+   zeromem(buf, sizeof(buf));
+#endif
+
+   return CRYPT_OK;
+#endif
+}
+
+#endif
+
+/* $Source: /cvs/libtom/libtomcrypt/src/mac/omac/omac_file.c,v $ */
+/* $Revision: 1.5 $ */
+/* $Date: 2006/11/03 00:39:49 $ */