Parsing of PKCS#8 encrypted private key files added and PKCS#12 basis

PKCS#8 encrypted key file support has been added to x509parse_key() with
support for some PCKS#12 PBE functions (pbeWithSHAAnd128BitRC4,
pbeWithSHAAnd3-KeyTripleDES-CBC and pbeWithSHAAnd2-KeyTripleDES-CBC)
diff --git a/include/polarssl/config.h b/include/polarssl/config.h
index 145b99b..579b5d6 100644
--- a/include/polarssl/config.h
+++ b/include/polarssl/config.h
@@ -722,6 +722,22 @@
  */
 
 /**
+ * \def POLARSSL_PKCS12_C
+ *
+ * Enable PKCS#12 PBE functions
+ * Adds algorithms for parsing PKCS#8 encrypted private keys
+ *
+ * Module:  library/pkcs12.c
+ * Caller:  library/x509parse.c
+ *
+ * Requires: POLARSSL_ASN1_PARSE_C
+ * Can use:  POLARSSL_SHA1_C, POLARSSL_DES_C, POLARSSL_ARC4_C
+ *
+ * This module enables PKCS#12 functions.
+ */
+#define POLARSSL_PKCS12_C
+
+/**
  * \def POLARSSL_RSA_C
  *
  * Enable the RSA public-key cryptosystem.
diff --git a/include/polarssl/error.h b/include/polarssl/error.h
index 73ebe89..1f7469c 100644
--- a/include/polarssl/error.h
+++ b/include/polarssl/error.h
@@ -74,6 +74,7 @@
  * High-level module nr (3 bits - 0x1...-0x8...)
  * Name     ID  Nr of Errors
  * PEM      1   9
+ * PKCS#12  1   3 (Started from top)
  * X509     2   21
  * DHM      3   6
  * RSA      4   9
diff --git a/include/polarssl/pkcs12.h b/include/polarssl/pkcs12.h
new file mode 100644
index 0000000..2a28c71
--- /dev/null
+++ b/include/polarssl/pkcs12.h
@@ -0,0 +1,139 @@
+/**
+ * \file pkcs12.h
+ *
+ * \brief PKCS#12 Personal Information Exchange Syntax
+ *
+ *  Copyright (C) 2006-2013, Brainspark B.V.
+ *
+ *  This file is part of PolarSSL (http://www.polarssl.org)
+ *  Lead Maintainer: Paul Bakker <polarssl_maintainer at polarssl.org>
+ *
+ *  All rights reserved.
+ *
+ *  This program is free software; you can redistribute it and/or modify
+ *  it under the terms of the GNU General Public License as published by
+ *  the Free Software Foundation; either version 2 of the License, or
+ *  (at your option) any later version.
+ *
+ *  This program is distributed in the hope that it will be useful,
+ *  but WITHOUT ANY WARRANTY; without even the implied warranty of
+ *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ *  GNU General Public License for more details.
+ *
+ *  You should have received a copy of the GNU General Public License along
+ *  with this program; if not, write to the Free Software Foundation, Inc.,
+ *  51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
+ */
+#ifndef POLARSSL_PKCS12_H
+#define POLARSSL_PKCS12_H
+
+#include <string.h>
+
+#include "md.h"
+#include "asn1.h"
+
+#define POLARSSL_ERR_PKCS12_BAD_INPUT_DATA                 -0x1F80  /**< Bad input parameters to function. */
+#define POLARSSL_ERR_PKCS12_FEATURE_UNAVAILABLE            -0x1F00  /**< Feature not available, e.g. unsupported encryption scheme. */
+#define POLARSSL_ERR_PKCS12_PBE_INVALID_FORMAT             -0x1E80  /**< PBE ASN.1 data not as expected. */
+
+#define PKCS12_DERIVE_KEY       1   /*< encryption/decryption key */
+#define PKCS12_DERIVE_IV        2   /*< initialization vector     */
+#define PKCS12_DERIVE_MAC_KEY   3   /*< integrity / MAC key       */
+
+#define PKCS12_PBE_ENCRYPT      1
+#define PKCS12_PBE_DECRYPT      2
+
+/*
+ * PKCS#12 PBE types
+ */
+#define OID_PKCS12               "\x2a\x86\x48\x86\xf7\x0d\x01\x0c"
+#define OID_PKCS12_PBE_SHA1_RC4_128         OID_PKCS12 "\x01\x01"
+#define OID_PKCS12_PBE_SHA1_DES3_EDE_CBC    OID_PKCS12 "\x01\x03"
+#define OID_PKCS12_PBE_SHA1_DES2_EDE_CBC    OID_PKCS12 "\x01\x04"
+
+#ifdef __cplusplus
+extern "C" {
+#endif
+
+/**
+ * \brief            PKCS12 Password Based function (encryption / decryption)
+ *                   for pbeWithSHAAnd128BitRC4
+ *
+ * \param pbe_params an ASN1 buffer containing the pkcs-12PbeParams structure
+ * \param mode       either PKCS12_PBE_ENCRYPT or PKCS12_PBE_DECRYPT
+ * \param pwd        the password used (may be NULL if no password is used)
+ * \param pwdlen     length of the password (may be 0)
+ * \param input      the input data
+ * \param len        data length
+ * \param output     the output buffer
+ */
+int pkcs12_pbe_sha1_rc4_128( asn1_buf *pbe_params, int mode,
+                             const unsigned char *pwd,  size_t pwdlen,
+                             const unsigned char *input, size_t len,
+                             unsigned char *output );
+
+/**
+ * \brief            PKCS12 Password Based function (encryption / decryption)
+ *                   for pbeWithSHAAnd3-KeyTripleDES-CBC
+ *
+ * \param pbe_params an ASN1 buffer containing the pkcs-12PbeParams structure
+ * \param mode       either PKCS12_PBE_ENCRYPT or PKCS12_PBE_DECRYPT
+ * \param pwd        the password used (may be NULL if no password is used)
+ * \param pwdlen     length of the password (may be 0)
+ * \param input      the input data
+ * \param len        data length
+ * \param output     the output buffer
+ */
+int pkcs12_pbe_sha1_des3_ede_cbc( asn1_buf *pbe_params, int mode,
+                                  const unsigned char *pwd,  size_t pwdlen,
+                                  const unsigned char *input, size_t len,
+                                  unsigned char *output );
+
+/**
+ * \brief            PKCS12 Password Based function (encryption / decryption)
+ *                   for pbeWithSHAAnd2-KeyTripleDES-CBC
+ *
+ * \param pbe_params an ASN1 buffer containing the pkcs-12PbeParams structure
+ * \param mode       either PKCS12_PBE_ENCRYPT or PKCS12_PBE_DECRYPT
+ * \param pwd        the password used (may be NULL if no password is used)
+ * \param pwdlen     length of the password (may be 0)
+ * \param input      the input data
+ * \param len        data length
+ * \param output     the output buffer
+ */
+int pkcs12_pbe_sha1_des2_ede_cbc( asn1_buf *pbe_params, int mode,
+                                  const unsigned char *pwd,  size_t pwdlen,
+                                  const unsigned char *input, size_t len,
+                                  unsigned char *output );
+
+/**
+ * \brief            The PKCS#12 derivation function uses a password and a salt
+ *                   to produce pseudo-random bits for a particular "purpose".
+ *
+ *                   Depending on the given id, this function can produce an
+ *                   encryption/decryption key, an nitialization vector or an
+ *                   integrity key.
+ *
+ * \param data       buffer to store the derived data in
+ * \param datalen    length to fill
+ * \param pwd        password to use (may be NULL if no password is used)
+ * \param pwdlen     length of the password (may be 0)
+ * \param salt       salt buffer to use
+ * \param saltlen    length of the salt
+ * \param md         md type to use during the derivation
+ * \param id         id that describes the purpose (can be PKCS12_DERIVE_KEY,
+ *                   PKCS12_DERIVE_IV or PKCS12_DERIVE_MAC_KEY)
+ * \param iterations number of iterations
+ *
+ * \return          0 if successful, or a MD, BIGNUM type error.
+ */
+int pkcs12_derivation( unsigned char *data, size_t datalen,
+                       const unsigned char *pwd, size_t pwdlen,
+                       const unsigned char *salt, size_t saltlen,
+                       md_type_t md, int id, int iterations );
+
+#ifdef __cplusplus
+}
+#endif
+
+#endif /* pkcs12.h */