diff libtomcrypt/src/pk/pkcs1/pkcs_1_i2osp.c @ 285:1b9e69c058d2

propagate from branch 'au.asn.ucc.matt.ltc.dropbear' (head 20dccfc09627970a312d77fb41dc2970b62689c3) to branch 'au.asn.ucc.matt.dropbear' (head fdf4a7a3b97ae5046139915de7e40399cceb2c01)
author Matt Johnston <matt@ucc.asn.au>
date Wed, 08 Mar 2006 13:23:58 +0000
parents
children 0cbe8f6dbf9e
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--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/libtomcrypt/src/pk/pkcs1/pkcs_1_i2osp.c	Wed Mar 08 13:23:58 2006 +0000
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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.
+ *
+ * Tom St Denis, [email protected], http://libtomcrypt.org
+ */
+#include "tomcrypt.h"
+
+/** 
+  @file pkcs_1_i2osp.c
+  Integer to Octet I2OSP, Tom St Denis 
+*/
+
+#ifdef PKCS_1
+
+/* always stores the same # of bytes, pads with leading zero bytes
+   as required
+ */
+
+/**
+   PKCS #1 Integer to binary
+   @param n             The integer to store
+   @param modulus_len   The length of the RSA modulus
+   @param out           [out] The destination for the integer
+   @return CRYPT_OK if successful
+*/
+int pkcs_1_i2osp(mp_int *n, unsigned long modulus_len, unsigned char *out)
+{
+   int err;
+   unsigned long size;
+
+   size = mp_unsigned_bin_size(n);
+
+   if (size > modulus_len) {
+      return CRYPT_BUFFER_OVERFLOW;
+   }
+
+   /* store it */
+   zeromem(out, modulus_len);
+   if ((err = mp_to_unsigned_bin(n, out+(modulus_len-size))) != MP_OKAY) {
+      return mpi_to_ltc_error(err);
+   }
+   return CRYPT_OK;
+}
+
+#endif /* PKCS_1 */
+
+
+/* $Source: /cvs/libtom/libtomcrypt/src/pk/pkcs1/pkcs_1_i2osp.c,v $ */
+/* $Revision: 1.3 $ */
+/* $Date: 2005/05/05 14:35:59 $ */