diff src/pk/rsa/rsa_decrypt_key.c @ 380:d5faf4814ddb libtomcrypt-orig libtomcrypt-1.16

Update to LibTomCrypt 1.16
author Matt Johnston <matt@ucc.asn.au>
date Thu, 11 Jan 2007 02:22:00 +0000
parents 59400faa4b44
children
line wrap: on
line diff
--- a/src/pk/rsa/rsa_decrypt_key.c	Wed Mar 08 12:58:00 2006 +0000
+++ b/src/pk/rsa/rsa_decrypt_key.c	Thu Jan 11 02:22:00 2007 +0000
@@ -6,19 +6,19 @@
  * The library is free for all purposes without any express
  * guarantee it works.
  *
- * Tom St Denis, [email protected], http://libtomcrypt.org
+ * Tom St Denis, [email protected], http://libtomcrypt.com
  */
 #include "tomcrypt.h"
 
 /**
   @file rsa_decrypt_key.c
-  RSA PKCS #1 OAEP Decryption, Tom St Denis
-*/  
+  RSA PKCS #1 Decryption, Tom St Denis and Andreas Lange
+*/
 
 #ifdef MRSA
 
 /**
-   (PKCS #1 v2.0) decrypt then OAEP depad  
+   PKCS #1 decrypt then v1.5 or OAEP depad
    @param in          The ciphertext
    @param inlen       The length of the ciphertext (octets)
    @param out         [out] The plaintext
@@ -26,20 +26,21 @@
    @param lparam      The system "lparam" value
    @param lparamlen   The length of the lparam value (octets)
    @param hash_idx    The index of the hash desired
+   @param padding     Type of padding (LTC_PKCS_1_OAEP or LTC_PKCS_1_V1_5)
    @param stat        [out] Result of the decryption, 1==valid, 0==invalid
    @param key         The corresponding private RSA key
    @return CRYPT_OK if succcessul (even if invalid)
 */
-int rsa_decrypt_key(const unsigned char *in,       unsigned long  inlen,
-                          unsigned char *out,      unsigned long *outlen, 
-                    const unsigned char *lparam,   unsigned long  lparamlen,
-                          int            hash_idx, int           *stat,
-                          rsa_key       *key)
+int rsa_decrypt_key_ex(const unsigned char *in,       unsigned long  inlen,
+                             unsigned char *out,      unsigned long *outlen,
+                       const unsigned char *lparam,   unsigned long  lparamlen,
+                             int            hash_idx, int            padding,
+                             int           *stat,     rsa_key       *key)
 {
   unsigned long modulus_bitlen, modulus_bytelen, x;
   int           err;
   unsigned char *tmp;
-  
+
   LTC_ARGCHK(out    != NULL);
   LTC_ARGCHK(outlen != NULL);
   LTC_ARGCHK(key    != NULL);
@@ -48,16 +49,25 @@
   /* default to invalid */
   *stat = 0;
 
-  /* valid hash ? */
-  if ((err = hash_is_valid(hash_idx)) != CRYPT_OK) {
-     return err;
+  /* valid padding? */
+
+  if ((padding != LTC_PKCS_1_V1_5) &&
+      (padding != LTC_PKCS_1_OAEP)) {
+    return CRYPT_PK_INVALID_PADDING;
   }
-  
+
+  if (padding == LTC_PKCS_1_OAEP) {
+    /* valid hash ? */
+    if ((err = hash_is_valid(hash_idx)) != CRYPT_OK) {
+       return err;
+    }
+  }
+
   /* get modulus len in bits */
-  modulus_bitlen = mp_count_bits(&(key->N));
+  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));
+  modulus_bytelen = mp_unsigned_bin_size( (key->N));
   if (modulus_bytelen != inlen) {
      return CRYPT_INVALID_PACKET;
   }
@@ -70,24 +80,26 @@
 
   /* rsa decode the packet */
   x = inlen;
-  if ((err = rsa_exptmod(in, inlen, tmp, &x, PK_PRIVATE, key)) != CRYPT_OK) {
+  if ((err = ltc_mp.rsa_me(in, inlen, tmp, &x, PK_PRIVATE, key)) != CRYPT_OK) {
      XFREE(tmp);
      return err;
   }
 
-  /* now OAEP decode the packet */
-  err = pkcs_1_oaep_decode(tmp, x, lparam, lparamlen, modulus_bitlen, hash_idx,
-                           out, outlen, stat);
+  if (padding == LTC_PKCS_1_OAEP) {
+    /* now OAEP decode the packet */
+    err = pkcs_1_oaep_decode(tmp, x, lparam, lparamlen, modulus_bitlen, hash_idx,
+                             out, outlen, stat);
+  } else {
+    /* now PKCS #1 v1.5 depad the packet */
+    err = pkcs_1_v1_5_decode(tmp, x, LTC_PKCS_1_EME, modulus_bitlen, out, outlen, stat);
+  }
+
   XFREE(tmp);
   return err;
 }
 
 #endif /* MRSA */
 
-
-
-
-
 /* $Source: /cvs/libtom/libtomcrypt/src/pk/rsa/rsa_decrypt_key.c,v $ */
-/* $Revision: 1.3 $ */
-/* $Date: 2005/05/05 14:35:59 $ */
+/* $Revision: 1.8 $ */
+/* $Date: 2006/11/01 09:18:22 $ */