1 files changed, 47 insertions, 0 deletions
diff --git a/libtomcrypt/src/pk/rsa/rsa_sign_saltlen_get.c b/libtomcrypt/src/pk/rsa/rsa_sign_saltlen_get.c
new file mode 100644
index 0000000..b217f94
--- /dev/null
+++ b/libtomcrypt/src/pk/rsa/rsa_sign_saltlen_get.c
@@ -0,0 +1,47 @@
+/* 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.
+ */
+#include "tomcrypt.h"
+
+/**
+  @file rsa_sign_saltlen_get.c
+  Retrieve the maximum size of the salt, Steffen Jaeckel.
+*/
+
+#ifdef LTC_MRSA
+
+/**
+  Retrieve the maximum possible size of the salt when creating a PKCS#1 PSS signature.
+  @param padding    Type of padding (LTC_PKCS_1_PSS only)
+  @param hash_idx   The index of the desired hash
+  @param key        The RSA key
+  @return The maximum salt length in bytes or INT_MAX on error.
+*/
+int rsa_sign_saltlen_get_max_ex(int padding, int hash_idx, rsa_key *key)
+{
+  int ret = INT_MAX;
+  LTC_ARGCHK(key != NULL);
+
+  if ((hash_is_valid(hash_idx) == CRYPT_OK) &&
+      (padding == LTC_PKCS_1_PSS))
+  {
+    ret = rsa_get_size(key);
+    if (ret < INT_MAX)
+    {
+      ret -= (hash_descriptor[hash_idx].hashsize + 2);
+    } /* if */
+  } /* if */
+
+  return ret;
+}
+
+#endif
+
+/* ref:         $Format:%D$ */
+/* git commit:  $Format:%H$ */
+/* commit time: $Format:%ai$ */