Add PKCS#8 private/public key processing tool

This tool works similar to 'openssl pkey' in that it allows to
read a private key from file and output the private or
corresponding public key to file. It also allows changing a
private key passphrase this way. This tool comes in handy when
replacing use of openssl in scripts.

The syntax is:

botan pkcs8 --in=private.pem --out=key_out.pem [--pubout] [--passin=] [--passout=] [--pbe=]

1 files changed, 66 insertions, 0 deletions

diff --git a/src/cmd/pkcs8.cpp b/src/cmd/pkcs8.cpp
new file mode 100644
index 000000000..88f6543de
--- /dev/null
+++ b/src/cmd/pkcs8.cpp
@@ -0,0 +1,66 @@
+/*
+* (C) 2015 René Korthaus
+*
+* Botan is released under the Simplified BSD License (see license.txt)
+*/
+
+#include "apps.h"
+#include <iostream>
+#include <fstream>
+#include <string>
+#include <memory>
+#include <chrono>
+#include <botan/pk_keys.h>
+#include <botan/pkcs8.h>
+#include <botan/x509_key.h>
+
+using namespace Botan;
+
+namespace {
+
+int pkcs8(int argc, char* argv[])
+   {
+   BOTAN_UNUSED(argc);
+   OptionParser opts("in=|out=|passin=|passout=|pbe=|pubout");
+   opts.parse(argv);
+
+   const std::string passin = opts.value_or_else("passin", "");
+   const std::string passout = opts.value_or_else("passout", "");
+   const std::string pbe = opts.value_or_else("pbe", "");
+       
+   try
+      {
+      std::ofstream out_key(opts.value("out"));
+         
+      if (!out_key)
+         {
+         std::cout << "Couldn't write key" << std::endl;
+         return 1;
+         }
+
+      AutoSeeded_RNG rng;
+      std::unique_ptr<Private_Key> key(PKCS8::load_key(opts.value("in"), rng, passin));
+                
+      if(opts.is_set("pubout"))
+         {
+         out_key << X509::PEM_encode(*key);
+         }
+         else
+         {
+         if(passout.empty())
+            out_key << PKCS8::PEM_encode(*key);
+         else
+            out_key << PKCS8::PEM_encode(*key, rng, passout, std::chrono::milliseconds(300), pbe);
+         }
+       }
+   catch(std::exception& e)
+      {
+      std::cout << "Exception caught: " << e.what() << std::endl;
+      }
+
+   return 0;
+   }
+
+REGISTER_APP(pkcs8);
+
+}