version 0.3.33

[fms.git] / libs / libtomcrypt / pk / rsa / rsa_sign_hash.c

diff --git a/libs/libtomcrypt/pk/rsa/rsa_sign_hash.c b/libs/libtomcrypt/pk/rsa/rsa_sign_hash.c
new file mode 100644 (file)
index 0000000..f10a97a
--- /dev/null
+++ b/libs/libtomcrypt/pk/rsa/rsa_sign_hash.c
@@ -0,0 +1,134 @@
+/* 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 rsa_sign_hash.c
+  RSA PKCS #1 v1.5 and v2 PSS sign hash, Tom St Denis and Andreas Lange
+*/
+
+#ifdef MRSA
+
+/**
+  PKCS #1 pad then sign
+  @param in        The hash to sign
+  @param inlen     The length of the hash to sign (octets)
+  @param out       [out] The signature
+  @param outlen    [in/out] The max size and resulting size of the signature
+  @param padding   Type of padding (LTC_PKCS_1_PSS or LTC_PKCS_1_V1_5)
+  @param prng      An active PRNG state
+  @param prng_idx  The index of the PRNG desired
+  @param hash_idx  The index of the hash desired
+  @param saltlen   The length of the salt desired (octets)
+  @param key       The private RSA key to use
+  @return CRYPT_OK if successful
+*/
+int rsa_sign_hash_ex(const unsigned char *in,       unsigned long  inlen,
+                           unsigned char *out,      unsigned long *outlen,
+                           int            padding,
+                           prng_state    *prng,     int            prng_idx,
+                           int            hash_idx, unsigned long  saltlen,
+                           rsa_key *key)
+{
+   unsigned long modulus_bitlen, modulus_bytelen, x, y;
+   int           err;
+
+   LTC_ARGCHK(in       != NULL);
+   LTC_ARGCHK(out      != NULL);
+   LTC_ARGCHK(outlen   != NULL);
+   LTC_ARGCHK(key      != NULL);
+
+   /* valid padding? */
+   if ((padding != LTC_PKCS_1_V1_5) && (padding != LTC_PKCS_1_PSS)) {
+     return CRYPT_PK_INVALID_PADDING;
+   }
+
+   if (padding == LTC_PKCS_1_PSS) {
+     /* valid prng and hash ? */
+     if ((err = prng_is_valid(prng_idx)) != CRYPT_OK) {
+        return err;
+     }
+     if ((err = hash_is_valid(hash_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) {
+     *outlen = modulus_bytelen;
+     return CRYPT_BUFFER_OVERFLOW;
+  }
+
+  if (padding == LTC_PKCS_1_PSS) {
+    /* PSS pad the key */
+    x = *outlen;
+    if ((err = pkcs_1_pss_encode(in, inlen, saltlen, prng, prng_idx,
+                                 hash_idx, modulus_bitlen, out, &x)) != CRYPT_OK) {
+       return err;
+    }
+  } else {
+    /* PKCS #1 v1.5 pad the hash */
+    unsigned char *tmpin;
+    ltc_asn1_list digestinfo[2], siginfo[2];
+
+    /* not all hashes have OIDs... so sad */
+    if (hash_descriptor[hash_idx].OIDlen == 0) {
+       return CRYPT_INVALID_ARG;
+    }
+
+    /* construct the SEQUENCE 
+      SEQUENCE {
+         SEQUENCE {hashoid OID
+                   blah    NULL
+         }
+         hash    OCTET STRING 
+      }
+   */
+    LTC_SET_ASN1(digestinfo, 0, LTC_ASN1_OBJECT_IDENTIFIER, hash_descriptor[hash_idx].OID, hash_descriptor[hash_idx].OIDlen);
+    LTC_SET_ASN1(digestinfo, 1, LTC_ASN1_NULL,              NULL,                          0);
+    LTC_SET_ASN1(siginfo,    0, LTC_ASN1_SEQUENCE,          digestinfo,                    2);
+    LTC_SET_ASN1(siginfo,    1, LTC_ASN1_OCTET_STRING,      in,                            inlen);
+
+    /* allocate memory for the encoding */
+    y = mp_unsigned_bin_size(key->N);
+    tmpin = XMALLOC(y);
+    if (tmpin == NULL) {
+       return CRYPT_MEM;
+    }
+
+    if ((err = der_encode_sequence(siginfo, 2, tmpin, &y)) != CRYPT_OK) {
+       XFREE(tmpin);
+       return err;
+    }
+
+    x = *outlen;
+    if ((err = pkcs_1_v1_5_encode(tmpin, y, LTC_PKCS_1_EMSA,
+                                  modulus_bitlen, NULL, 0,
+                                  out, &x)) != CRYPT_OK) {
+      XFREE(tmpin);
+      return err;
+    }
+    XFREE(tmpin);
+  }
+
+  /* RSA encode it */
+  return ltc_mp.rsa_me(out, x, out, outlen, PK_PRIVATE, key);
+}
+
+#endif /* MRSA */
+
+/* $Source: /cvs/libtom/libtomcrypt/src/pk/rsa/rsa_sign_hash.c,v $ */
+/* $Revision: 1.9 $ */
+/* $Date: 2006/11/09 23:15:39 $ */