Remove global state dependency from pbes1

1 files changed, 38 insertions, 2 deletions

diff --git a/src/pbe/get_pbe.cpp b/src/pbe/get_pbe.cpp
index 103e64a0c..d5960f283 100644
--- a/src/pbe/get_pbe.cpp
+++ b/src/pbe/get_pbe.cpp
@@ -6,6 +6,8 @@
 #include <botan/get_pbe.h>
 #include <botan/oids.h>
 #include <botan/scan_name.h>
+#include <botan/parsing.h>
+#include <botan/libstate.h>
 
 #if defined(BOTAN_HAS_PBE_PKCS_V15)
   #include <botan/pbes1.h>
@@ -17,6 +19,40 @@
 
 namespace Botan {
 
+namespace {
+
+PBE* make_pbe_pkcs15(const std::string& cipher,
+                     const std::string& digest,
+                     Cipher_Dir direction)
+   {
+   std::vector<std::string> cipher_spec = split_on(cipher, '/');
+   if(cipher_spec.size() != 2)
+      throw Invalid_Argument("PBE-PKCS5 v1.5: Invalid cipher spec " + cipher);
+
+   const std::string cipher_algo = global_state().deref_alias(cipher_spec[0]);
+   const std::string cipher_mode = cipher_spec[1];
+
+   if(cipher_mode != "CBC")
+      throw Invalid_Argument("PBE-PKCS5 v1.5: Invalid cipher " + cipher);
+
+   Algorithm_Factory& af = global_state().algorithm_factory();
+
+   const BlockCipher* block_cipher = af.make_block_cipher(cipher_algo);
+   if(!block_cipher)
+      throw Algorithm_Not_Found(cipher_algo);
+
+   const HashFunction* hash_function = af.make_hash_function(digest);
+   if(!hash_function)
+      throw Algorithm_Not_Found(digest);
+
+   return new PBE_PKCS5v15(block_cipher->clone(),
+                           hash_function->clone(),
+                           direction);
+
+   }
+
+}
+
 /*************************************************
 * Get an encryption PBE, set new parameters      *
 *************************************************/
@@ -33,7 +69,7 @@ PBE* get_pbe(const std::string& pbe_name)
 
 #if defined(BOTAN_HAS_PBE_PKCS_V15)
    if(pbe == "PBE-PKCS5v15")
-      return new PBE_PKCS5v15(digest, cipher, ENCRYPTION);
+      return make_pbe_pkcs15(cipher, digest, ENCRYPTION);
 #endif
 
 #if defined(BOTAN_HAS_PBE_PKCS_V20)
@@ -60,7 +96,7 @@ PBE* get_pbe(const OID& pbe_oid, DataSource& params)
       const std::string digest = request.arg(0);
       const std::string cipher = request.arg(1);
 
-      PBE* pbe = new PBE_PKCS5v15(digest, cipher, DECRYPTION);
+      PBE* pbe = make_pbe_pkcs15(cipher, digest, DECRYPTION);
       pbe->decode_params(params);
       return pbe;
       }