Modify the S2K interface. Instead of being stateful in terms of the salt

and iteration count, force it to be passed to each call to derive_key.
So remove current_salt, set_iterations, new_random_salt, and change_salt
functions from S2K interface.

Update examples and test application to match.

While I was in there, change the passhash example to use 64 bit salts
and 128 bit PBKDF2 outputs.

2 files changed, 9 insertions, 6 deletions

diff --git a/src/s2k/pgps2k/pgp_s2k.cpp b/src/s2k/pgps2k/pgp_s2k.cpp
index 86394d84d..49ff6892c 100644
--- a/src/s2k/pgps2k/pgp_s2k.cpp
+++ b/src/s2k/pgps2k/pgp_s2k.cpp
@@ -14,9 +14,10 @@ namespace Botan {
 /*
 * Derive a key using the OpenPGP S2K algorithm
 */
-OctetString OpenPGP_S2K::derive(u32bit key_len, const std::string& passphrase,
-                                const byte salt_buf[], u32bit salt_size,
-                                u32bit iterations) const
+OctetString OpenPGP_S2K::derive_key(u32bit key_len,
+                                    const std::string& passphrase,
+                                    const byte salt_buf[], u32bit salt_size,
+                                    u32bit iterations) const
    {
    SecureVector<byte> key(key_len), hash_buf;
 
diff --git a/src/s2k/pgps2k/pgp_s2k.h b/src/s2k/pgps2k/pgp_s2k.h
index 00e95f7fa..7f25623f3 100644
--- a/src/s2k/pgps2k/pgp_s2k.h
+++ b/src/s2k/pgps2k/pgp_s2k.h
@@ -22,12 +22,14 @@ class BOTAN_DLL OpenPGP_S2K : public S2K
       std::string name() const;
       S2K* clone() const;
 
+      OctetString derive_key(u32bit output_len,
+                             const std::string& passphrase,
+                             const byte salt[], u32bit salt_len,
+                             u32bit iterations) const;
+
       OpenPGP_S2K(HashFunction* hash_in) : hash(hash_in) {}
       ~OpenPGP_S2K() { delete hash; }
    private:
-      OctetString derive(u32bit, const std::string&,
-                         const byte[], u32bit, u32bit) const;
-
       HashFunction* hash;
    };