--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/src/pk/rsa/rsa_v15_encrypt_key.c	Fri May 06 13:23:02 2005 +0000
@@ -0,0 +1,68 @@
+/* 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 rsa_v15_encrypt_key.c
+  RSA PKCS v1.5 Encryption, Tom St Denis
+*/  
+
+#ifdef MRSA
+
+/** 
+   PKCS #1 v1.5 pad then encrypt
+   @param in          The plaintext
+   @param inlen       The length of the plaintext (octets)
+   @param out         [out] The ciphertext
+   @param outlen      [in/out] The max size and resulting size of the ciphertext 
+   @param prng        An active PRNG
+   @param prng_idx    The index of the desired PRNG
+   @param key         The public RSA key
+   @return CRYPT_OK if successful
+*/   
+int rsa_v15_encrypt_key(const unsigned char *in,    unsigned long  inlen,
+                              unsigned char *out,   unsigned long *outlen,
+                              prng_state    *prng,  int            prng_idx, 
+                              rsa_key       *key)
+{
+  unsigned long modulus_bitlen, modulus_bytelen, x;
+  int           err;
+  
+  LTC_ARGCHK(in     != NULL);
+  LTC_ARGCHK(out    != NULL);
+  LTC_ARGCHK(outlen != NULL);
+  LTC_ARGCHK(key    != NULL);
+  
+  /* valid prng? */
+  if ((err = prng_is_valid(prng_idx)) != CRYPT_OK) {
+     return err;
+  }
+  
+  /* get modulus len in bits */
+  modulus_bitlen = mp_count_bits(&(key->N));
+
+  /* outlen must be at least the size of the modulus */
+  modulus_bytelen = mp_unsigned_bin_size(&(key->N));
+  if (modulus_bytelen > *outlen) {
+     return CRYPT_BUFFER_OVERFLOW;
+  }
+  
+  /* pad it */
+  x = *outlen;
+  if ((err = pkcs_1_v15_es_encode(in, inlen, modulus_bitlen, prng, prng_idx, out, &x)) != CRYPT_OK) {
+     return err;
+  }
+  
+  /* encrypt it */
+  return rsa_exptmod(out, x, out, outlen, PK_PUBLIC, key);
+}
+
+#endif