diff --git a/include/polarssl/asn1.h b/include/polarssl/asn1.h
index 893292d..8c7579d 100644
--- a/include/polarssl/asn1.h
+++ b/include/polarssl/asn1.h
@@ -93,6 +93,11 @@
 /** Returns the size of the binary string, without the trailing \\0 */
 #define OID_SIZE(x) (sizeof(x) - 1)
 
+/** Compares two asn1_buf structures for the same OID */
+#define OID_CMP(oid_str, oid_buf)                                   \
+        ( ( OID_SIZE(oid_str) == (oid_buf)->len ) &&                \
+          memcmp( (oid_str), (oid_buf)->p, (oid_buf)->len) == 0 )
+
 #ifdef __cplusplus
 extern "C" {
 #endif
diff --git a/include/polarssl/config.h b/include/polarssl/config.h
index 40ea455..5d27db7 100644
--- a/include/polarssl/config.h
+++ b/include/polarssl/config.h
@@ -710,6 +710,20 @@
 #define POLARSSL_NET_C
 
 /**
+ * \def POLARSSL_OID_C
+ *
+ * Enable the OID database
+ *
+ * Module:  library/oid.c
+ * Caller:  library/rsa.c
+ *          library/x509parse.c
+ *          library/x509write.c
+ *
+ * This modules translates between OIDs and internal values.
+ */
+#define POLARSSL_OID_C
+
+/**
  * \def POLARSSL_PADLOCK_C
  *
  * Enable VIA Padlock support on x86.
@@ -775,7 +789,7 @@
  *          library/ssl_tls.c
  *          library/x509.c
  *
- * Requires: POLARSSL_BIGNUM_C
+ * Requires: POLARSSL_BIGNUM_C, POLARSSL_OID_C
  *
  * This module is required for SSL/TLS and MD5-signed certificates.
  */
@@ -911,7 +925,8 @@
  *          library/ssl_srv.c
  *          library/ssl_tls.c
  *
- * Requires: POLARSSL_ASN1_PARSE_C, POLARSSL_BIGNUM_C, POLARSSL_RSA_C
+ * Requires: POLARSSL_ASN1_PARSE_C, POLARSSL_BIGNUM_C, POLARSSL_OID_C,
+ *           POLARSSL_RSA_C
  *
  * This module is required for X.509 certificate parsing.
  */
@@ -924,7 +939,7 @@
  *
  * Module:  library/x509write.c
  *
- * Requires: POLARSSL_BIGNUM_C, POLARSSL_RSA_C
+ * Requires: POLARSSL_BIGNUM_C, POLARSSL_OID_C, POLARSSL_RSA_C
  *
  * This module is required for X.509 certificate request writing.
  */
diff --git a/include/polarssl/error.h b/include/polarssl/error.h
index 32dc0a7..a084243 100644
--- a/include/polarssl/error.h
+++ b/include/polarssl/error.h
@@ -55,6 +55,7 @@
  * CAMELLIA  2  0x0024-0x0026
  * XTEA      1  0x0028-0x0028
  * BASE64    2  0x002A-0x002C
+ * OID       1  0x002E-0x002E
  * PADLOCK   1  0x0030-0x0030
  * DES       1  0x0032-0x0032
  * CTR_DBRG  3  0x0034-0x003A
diff --git a/include/polarssl/oid.h b/include/polarssl/oid.h
new file mode 100644
index 0000000..8b45f4f
--- /dev/null
+++ b/include/polarssl/oid.h
@@ -0,0 +1,298 @@
+/**
+ * \file oid.h
+ *
+ * \brief Object Identifier (OID) database
+ *
+ *  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_OID_H
+#define POLARSSL_OID_H
+
+#include <string.h>
+#include "asn1.h"
+#include "md.h"
+#include "x509.h"
+
+#define POLARSSL_ERR_OID_NOT_FOUND                         -0x002E  /**< OID is not found. */
+
+/*
+ * Top level OID tuples
+ */
+#define OID_ISO_MEMBER_BODIES           "\x2a"          /* {iso(1) member-body(2)} */
+#define OID_ISO_IDENTIFIED_ORG          "\x2b"          /* {iso(1) identified-organization(3)} */
+#define OID_ISO_CCITT_DS                "\x55"          /* {joint-iso-ccitt(2) ds(5)} */
+#define OID_ISO_ITU_COUNTRY             "\x60"          /* {joint-iso-itu-t(2) country(16)} */
+
+/*
+ * ISO Member bodies OID parts
+ */
+#define OID_COUNTRY_US                  "\x86\x48"      /* {us(840)} */
+#define OID_ORG_RSA_DATA_SECURITY       "\x86\xf7\x0d"  /* {rsadsi(113549)} */
+#define OID_RSA_COMPANY                 OID_ISO_MEMBER_BODIES OID_COUNTRY_US    \
+                                        OID_ORG_RSA_DATA_SECURITY /* {iso(1) member-body(2) us(840) rsadsi(113549)} */
+
+/*
+ * ISO Identified organization OID parts
+ */
+#define OID_ORG_DOD                     "\x06"          /* {dod(6)} */
+#define OID_OIW_SECSIG_SHA1             "\x0e\x03\x02\x1a"
+
+/*
+ * ISO ITU OID parts
+ */
+#define OID_ORGANIZATION                "\x01"          /* {organization(1)} */
+#define OID_ISO_ITU_US_ORG              OID_ISO_ITU_COUNTRY OID_COUNTRY_US OID_ORGANIZATION /* {joint-iso-itu-t(2) country(16) us(840) organization(1)} */
+
+#define OID_ORG_GOV                     "\x65"          /* {gov(101)} */
+#define OID_GOV                         OID_ISO_ITU_US_ORG OID_ORG_GOV /* {joint-iso-itu-t(2) country(16) us(840) organization(1) gov(101)} */
+
+#define OID_ORG_NETSCAPE                "\x86\xF8\x42"  /* {netscape(113730)} */
+#define OID_NETSCAPE                    OID_ISO_ITU_US_ORG OID_ORG_NETSCAPE /* Netscape OID {joint-iso-itu-t(2) country(16) us(840) organization(1) netscape(113730)} */
+
+/* ISO arc for standard certificate and CRL extensions */
+#define OID_ID_CE                       OID_ISO_CCITT_DS "\x1D" /**< id-ce OBJECT IDENTIFIER  ::=  {joint-iso-ccitt(2) ds(5) 29} */
+
+/**
+ * Private Internet Extensions
+ * { iso(1) identified-organization(3) dod(6) internet(1)
+ *                      security(5) mechanisms(5) pkix(7) }
+ */
+#define OID_PKIX                        OID_ISO_IDENTIFIED_ORG OID_ORG_DOD "\x01\x05\x05\x07"
+
+/*
+ * Arc for standard naming attributes
+ */
+#define OID_AT                          OID_ISO_CCITT_DS "\x04" /**< id-at OBJECT IDENTIFIER ::= {joint-iso-ccitt(2) ds(5) 4} */
+#define OID_AT_CN                       OID_AT "\x03" /**< id-at-commonName AttributeType:= {id-at 3} */
+#define OID_AT_COUNTRY                  OID_AT "\x06" /**< id-at-countryName AttributeType:= {id-at 6} */
+#define OID_AT_LOCALITY                 OID_AT "\x07" /**< id-at-locality AttributeType:= {id-at 7} */
+#define OID_AT_STATE                    OID_AT "\x08" /**< id-at-state AttributeType:= {id-at 8} */
+#define OID_AT_ORGANIZATION             OID_AT "\x0A" /**< id-at-organizationName AttributeType:= {id-at 10} */
+#define OID_AT_ORG_UNIT                 OID_AT "\x0B" /**< id-at-organizationalUnitName AttributeType:= {id-at 11} */
+
+/*
+ * OIDs for standard certificate extensions
+ */
+#define OID_AUTHORITY_KEY_IDENTIFIER    OID_ID_CE "\x23" /**< id-ce-authorityKeyIdentifier OBJECT IDENTIFIER ::=  { id-ce 35 } */
+#define OID_SUBJECT_KEY_IDENTIFIER      OID_ID_CE "\x0E" /**< id-ce-subjectKeyIdentifier OBJECT IDENTIFIER ::=  { id-ce 14 } */
+#define OID_KEY_USAGE                   OID_ID_CE "\x0F" /**< id-ce-keyUsage OBJECT IDENTIFIER ::=  { id-ce 15 } */
+#define OID_CERTIFICATE_POLICIES        OID_ID_CE "\x20" /**< id-ce-certificatePolicies OBJECT IDENTIFIER ::=  { id-ce 32 } */
+#define OID_POLICY_MAPPINGS             OID_ID_CE "\x21" /**< id-ce-policyMappings OBJECT IDENTIFIER ::=  { id-ce 33 } */
+#define OID_SUBJECT_ALT_NAME            OID_ID_CE "\x11" /**< id-ce-subjectAltName OBJECT IDENTIFIER ::=  { id-ce 17 } */
+#define OID_ISSUER_ALT_NAME             OID_ID_CE "\x12" /**< id-ce-issuerAltName OBJECT IDENTIFIER ::=  { id-ce 18 } */
+#define OID_SUBJECT_DIRECTORY_ATTRS     OID_ID_CE "\x09" /**< id-ce-subjectDirectoryAttributes OBJECT IDENTIFIER ::=  { id-ce 9 } */
+#define OID_BASIC_CONSTRAINTS           OID_ID_CE "\x13" /**< id-ce-basicConstraints OBJECT IDENTIFIER ::=  { id-ce 19 } */
+#define OID_NAME_CONSTRAINTS            OID_ID_CE "\x1E" /**< id-ce-nameConstraints OBJECT IDENTIFIER ::=  { id-ce 30 } */
+#define OID_POLICY_CONSTRAINTS          OID_ID_CE "\x24" /**< id-ce-policyConstraints OBJECT IDENTIFIER ::=  { id-ce 36 } */
+#define OID_EXTENDED_KEY_USAGE          OID_ID_CE "\x25" /**< id-ce-extKeyUsage OBJECT IDENTIFIER ::= { id-ce 37 } */
+#define OID_CRL_DISTRIBUTION_POINTS     OID_ID_CE "\x1F" /**< id-ce-cRLDistributionPoints OBJECT IDENTIFIER ::=  { id-ce 31 } */
+#define OID_INIHIBIT_ANYPOLICY          OID_ID_CE "\x36" /**< id-ce-inhibitAnyPolicy OBJECT IDENTIFIER ::=  { id-ce 54 } */
+#define OID_FRESHEST_CRL                OID_ID_CE "\x2E" /**< id-ce-freshestCRL OBJECT IDENTIFIER ::=  { id-ce 46 } */
+
+/*
+ * Netscape certificate extensions
+ */
+#define OID_NS_CERT                 OID_NETSCAPE "\x01"
+#define OID_NS_CERT_TYPE            OID_NS_CERT  "\x01"
+#define OID_NS_BASE_URL             OID_NS_CERT  "\x02"
+#define OID_NS_REVOCATION_URL       OID_NS_CERT  "\x03"
+#define OID_NS_CA_REVOCATION_URL    OID_NS_CERT  "\x04"
+#define OID_NS_RENEWAL_URL          OID_NS_CERT  "\x07"
+#define OID_NS_CA_POLICY_URL        OID_NS_CERT  "\x08"
+#define OID_NS_SSL_SERVER_NAME      OID_NS_CERT  "\x0C"
+#define OID_NS_COMMENT              OID_NS_CERT  "\x0D"
+#define OID_NS_DATA_TYPE            OID_NETSCAPE "\x02"
+#define OID_NS_CERT_SEQUENCE        OID_NS_DATA_TYPE "\x05"
+
+/*
+ * OIDs for CRL extensions
+ */
+#define OID_PRIVATE_KEY_USAGE_PERIOD    OID_ID_CE "\x10"
+#define OID_CRL_NUMBER                  OID_ID_CE "\x14" /**< id-ce-cRLNumber OBJECT IDENTIFIER ::= { id-ce 20 } */
+
+/*
+ * X.509 v3 Extended key usage OIDs
+ */
+#define OID_ANY_EXTENDED_KEY_USAGE      OID_EXTENDED_KEY_USAGE "\x00" /**< anyExtendedKeyUsage OBJECT IDENTIFIER ::= { id-ce-extKeyUsage 0 } */
+
+#define OID_KP                          OID_PKIX "\x03" /**< id-kp OBJECT IDENTIFIER ::= { id-pkix 3 } */
+#define OID_SERVER_AUTH                 OID_KP "\x01" /**< id-kp-serverAuth OBJECT IDENTIFIER ::= { id-kp 1 } */
+#define OID_CLIENT_AUTH                 OID_KP "\x02" /**< id-kp-clientAuth OBJECT IDENTIFIER ::= { id-kp 2 } */
+#define OID_CODE_SIGNING                OID_KP "\x03" /**< id-kp-codeSigning OBJECT IDENTIFIER ::= { id-kp 3 } */
+#define OID_EMAIL_PROTECTION            OID_KP "\x04" /**< id-kp-emailProtection OBJECT IDENTIFIER ::= { id-kp 4 } */
+#define OID_TIME_STAMPING               OID_KP "\x08" /**< id-kp-timeStamping OBJECT IDENTIFIER ::= { id-kp 8 } */
+#define OID_OCSP_SIGNING                OID_KP "\x09" /**< id-kp-OCSPSigning OBJECT IDENTIFIER ::= { id-kp 9 } */
+
+#define OID_PKCS                OID_RSA_COMPANY "\x01" /**< pkcs OBJECT IDENTIFIER ::= { iso(1) member-body(2) us(840) rsadsi(113549) 1 } */
+#define OID_PKCS1               OID_PKCS "\x01" /**< pkcs-1 OBJECT IDENTIFIER ::= { iso(1) member-body(2) us(840) rsadsi(113549) pkcs(1) 1 } */
+#define OID_PKCS9               OID_PKCS "\x09" /**< pkcs-9 OBJECT IDENTIFIER ::= { iso(1) member-body(2) us(840) rsadsi(113549) pkcs(1) 9 } */
+
+#define OID_PKCS1_RSA           OID_PKCS1 "\x01" /**< rsaEncryption OBJECT IDENTIFIER ::= { pkcs-1 1 } */
+#define OID_PKCS1_MD2           OID_PKCS1 "\x02" /**< md2WithRSAEncryption ::= { pkcs-1 2 } */
+#define OID_PKCS1_MD4           OID_PKCS1 "\x03" /**< md4WithRSAEncryption ::= { pkcs-1 3 } */
+#define OID_PKCS1_MD5           OID_PKCS1 "\x04" /**< md5WithRSAEncryption ::= { pkcs-1 4 } */
+#define OID_PKCS1_SHA1          OID_PKCS1 "\x05" /**< sha1WithRSAEncryption ::= { pkcs-1 5 } */
+#define OID_PKCS1_SHA224        OID_PKCS1 "\x0e" /**< sha224WithRSAEncryption ::= { pkcs-1 14 } */
+#define OID_PKCS1_SHA256        OID_PKCS1 "\x0b" /**< sha256WithRSAEncryption ::= { pkcs-1 11 } */
+#define OID_PKCS1_SHA384        OID_PKCS1 "\x0c" /**< sha384WithRSAEncryption ::= { pkcs-1 12 } */
+#define OID_PKCS1_SHA512        OID_PKCS1 "\x0d" /**< sha512WithRSAEncryption ::= { pkcs-1 13 } */
+
+#define OID_RSA_SHA_OBS         "\x2B\x0E\x03\x02\x1D"
+
+#define OID_PKCS9_EMAIL         OID_PKCS9 "\x01" /**< emailAddress AttributeType ::= { pkcs-9 1 } */
+
+#define OID_DIGEST_ALG_MD2              OID_RSA_COMPANY "\x02\x02" /**< id-md2 OBJECT IDENTIFIER ::= { iso(1) member-body(2) us(840) rsadsi(113549) digestAlgorithm(2) 2 } */
+#define OID_DIGEST_ALG_MD4              OID_RSA_COMPANY "\x02\x04" /**< id-md4 OBJECT IDENTIFIER ::= { iso(1) member-body(2) us(840) rsadsi(113549) digestAlgorithm(2) 4 } */
+#define OID_DIGEST_ALG_MD5              OID_RSA_COMPANY "\x02\x05" /**< id-md5 OBJECT IDENTIFIER ::= { iso(1) member-body(2) us(840) rsadsi(113549) digestAlgorithm(2) 5 } */
+#define OID_DIGEST_ALG_SHA1             OID_ISO_IDENTIFIED_ORG OID_OIW_SECSIG_SHA1 /**< id-sha1 OBJECT IDENTIFIER ::= { iso(1) identified-organization(3) oiw(14) secsig(3) algorithms(2) 26 } */
+#define OID_DIGEST_ALG_SHA224           OID_GOV "\x03\x04\x02\x04" /**< id-sha224 OBJECT IDENTIFIER ::= { joint-iso-itu-t(2) country(16) us(840) organization(1) gov(101) csor(3) nistalgorithm(4) hashalgs(2) 4 } */
+#define OID_DIGEST_ALG_SHA256           OID_GOV "\x03\x04\x02\x01" /**< id-sha256 OBJECT IDENTIFIER ::= { joint-iso-itu-t(2) country(16) us(840) organization(1) gov(101) csor(3) nistalgorithm(4) hashalgs(2) 1 } */
+
+#define OID_DIGEST_ALG_SHA384           OID_GOV "\x03\x04\x02\x02" /**< id-sha384 OBJECT IDENTIFIER ::= { joint-iso-itu-t(2) country(16) us(840) organization(1) gov(101) csor(3) nistalgorithm(4) hashalgs(2) 2 } */
+
+#define OID_DIGEST_ALG_SHA512           OID_GOV "\x03\x04\x02\x03" /**< id-sha512 OBJECT IDENTIFIER ::= { joint-iso-itu-t(2) country(16) us(840) organization(1) gov(101) csor(3) nistalgorithm(4) hashalgs(2) 3 } */
+
+#ifdef __cplusplus
+extern "C" {
+#endif
+
+/**
+ * \brief Base OID descriptor structure
+ */
+typedef struct {
+    const char *asn1;               /*!< OID ASN.1 representation       */
+    const char *name;               /*!< official name (e.g. from RFC)  */
+    const char *description;        /*!< human friendly description     */
+} oid_descriptor_t;
+
+/**
+ * \brief           Translate an ASN.1 OID into its numeric representation
+ *                  (e.g. "\x2A\x86\x48\x86\xF7\x0D" into "1.2.840.113549")
+ *
+ * \param buf       buffer to put representation in
+ * \param size      size of the buffer
+ * \param oid       OID to translate
+ *
+ * \return          POLARSSL_ERR_DEBUG_BUF_TOO_SMALL or actual length used
+ */
+int oid_get_numeric_string( char *buf, size_t size, const asn1_buf *oid );
+
+/**
+ * \brief          Translate an X.509 extension OID into local values
+ *
+ * \param oid      OID to use
+ * \param ext_type place to store the extension type
+ *
+ * \return         0 if successful, or POLARSSL_ERR_OID_NOT_FOUND
+ */
+int oid_get_x509_ext_type( const asn1_buf *oid, int *ext_type );
+
+/**
+ * \brief          Translate an X.509 attribute type OID into the short name
+ *                 (e.g. the OID for an X520 Common Name into "CN")
+ *
+ * \param oid      OID to use
+ * \param short_name    place to store the string pointer
+ *
+ * \return         0 if successful, or POLARSSL_ERR_OID_NOT_FOUND
+ */
+int oid_get_attr_short_name( const asn1_buf *oid, const char **short_name );
+
+/**
+ * \brief          Translate PublicKeyAlgorithm OID into pk_type
+ *
+ * \param oid      OID to use
+ * \param pk_alg   place to store public key algorithm
+ *
+ * \return         0 if successful, or POLARSSL_ERR_OID_NOT_FOUND
+ */
+int oid_get_pk_alg( const asn1_buf *oid, pk_type_t *pk_alg );
+
+/**
+ * \brief          Translate SignatureAlgorithm OID into md_type and pk_type
+ *
+ * \param oid      OID to use
+ * \param md_alg   place to store message digest algorithm
+ * \param pk_alg   place to store public key algorithm
+ *
+ * \return         0 if successful, or POLARSSL_ERR_OID_NOT_FOUND
+ */
+int oid_get_sig_alg( const asn1_buf *oid,
+                     md_type_t *md_alg, pk_type_t *pk_alg );
+
+/**
+ * \brief          Translate SignatureAlgorithm OID into description
+ *
+ * \param oid      OID to use
+ * \param desc     place to store string pointer
+ *
+ * \return         0 if successful, or POLARSSL_ERR_OID_NOT_FOUND
+ */
+int oid_get_sig_alg_desc( const asn1_buf *oid, const char **desc );
+
+/**
+ * \brief          Translate md_type and pk_type into SignatureAlgorithm OID
+ *
+ * \param md_alg   message digest algorithm
+ * \param pk_alg   public key algorithm
+ * \param oid      place to store ASN.1 OID string pointer
+ *
+ * \return         0 if successful, or POLARSSL_ERR_OID_NOT_FOUND
+ */
+int oid_get_oid_by_sig_alg( pk_type_t pk_alg, md_type_t md_alg,
+                            const char **oid_str );
+
+/**
+ * \brief          Translate hash algorithm OID into md_type
+ *
+ * \param oid      OID to use
+ * \param md_alg   place to store message digest algorithm
+ *
+ * \return         0 if successful, or POLARSSL_ERR_OID_NOT_FOUND
+ */
+int oid_get_md_alg( const asn1_buf *oid, md_type_t *md_alg );
+
+/**
+ * \brief          Translate Extended Key Usage OID into description
+ *
+ * \param oid      OID to use
+ * \param desc     place to store string pointer
+ *
+ * \return         0 if successful, or POLARSSL_ERR_OID_NOT_FOUND
+ */
+int oid_get_extended_key_usage( const asn1_buf *oid, const char **desc );
+
+/**
+ * \brief          Translate md_type into hash algorithm OID
+ *
+ * \param md_alg   message digest algorithm
+ * \param oid      place to store ASN.1 OID string pointer
+ *
+ * \return         0 if successful, or POLARSSL_ERR_OID_NOT_FOUND
+ */
+int oid_get_oid_by_md( md_type_t md_alg, const char **oid_str );
+
+#ifdef __cplusplus
+}
+#endif
+
+#endif /* oid.h */
diff --git a/include/polarssl/rsa.h b/include/polarssl/rsa.h
index f9a0220..8342eec 100644
--- a/include/polarssl/rsa.h
+++ b/include/polarssl/rsa.h
@@ -28,6 +28,7 @@
 #define POLARSSL_RSA_H
 
 #include "bignum.h"
+#include "md.h"
 
 /*
  * RSA Error codes
@@ -43,18 +44,8 @@
 #define POLARSSL_ERR_RSA_RNG_FAILED                        -0x4480  /**< The random generator failed to generate non-zeros. */
 
 /*
- * PKCS#1 constants
+ * RSA constants
  */
-#define SIG_RSA_RAW     0
-#define SIG_RSA_MD2     2
-#define SIG_RSA_MD4     3
-#define SIG_RSA_MD5     4
-#define SIG_RSA_SHA1    5
-#define SIG_RSA_SHA224 14
-#define SIG_RSA_SHA256 11
-#define SIG_RSA_SHA384 12
-#define SIG_RSA_SHA512 13
-
 #define RSA_PUBLIC      0
 #define RSA_PRIVATE     1
 
@@ -64,71 +55,6 @@
 #define RSA_SIGN        1
 #define RSA_CRYPT       2
 
-#define ASN1_STR_CONSTRUCTED_SEQUENCE   "\x30"
-#define ASN1_STR_NULL                   "\x05"
-#define ASN1_STR_OID                    "\x06"
-#define ASN1_STR_OCTET_STRING           "\x04"
-
-#define OID_DIGEST_ALG_MDX              "\x2A\x86\x48\x86\xF7\x0D\x02\x00"
-#define OID_HASH_ALG_SHA1               "\x2b\x0e\x03\x02\x1a"
-#define OID_HASH_ALG_SHA2X              "\x60\x86\x48\x01\x65\x03\x04\x02\x00"
-
-#define OID_ISO_MEMBER_BODIES           "\x2a"
-#define OID_ISO_IDENTIFIED_ORG          "\x2b"
-
-/*
- * ISO Member bodies OID parts
- */
-#define OID_COUNTRY_US                  "\x86\x48"
-#define OID_RSA_DATA_SECURITY           "\x86\xf7\x0d"
-
-/*
- * ISO Identified organization OID parts
- */
-#define OID_OIW_SECSIG_SHA1             "\x0e\x03\x02\x1a"
-
-/*
- * DigestInfo ::= SEQUENCE {
- *   digestAlgorithm DigestAlgorithmIdentifier,
- *   digest Digest }
- *
- * DigestAlgorithmIdentifier ::= AlgorithmIdentifier
- *
- * Digest ::= OCTET STRING
- */
-#define ASN1_HASH_MDX                           \
-(                                               \
-    ASN1_STR_CONSTRUCTED_SEQUENCE "\x20"        \
-      ASN1_STR_CONSTRUCTED_SEQUENCE "\x0C"      \
-        ASN1_STR_OID "\x08"                     \
-      OID_DIGEST_ALG_MDX                        \
-    ASN1_STR_NULL "\x00"                        \
-      ASN1_STR_OCTET_STRING "\x10"              \
-)
-
-#define ASN1_HASH_SHA1                          \
-    ASN1_STR_CONSTRUCTED_SEQUENCE "\x21"        \
-      ASN1_STR_CONSTRUCTED_SEQUENCE "\x09"      \
-        ASN1_STR_OID "\x05"                     \
-      OID_HASH_ALG_SHA1                         \
-        ASN1_STR_NULL "\x00"                    \
-      ASN1_STR_OCTET_STRING "\x14"
-
-#define ASN1_HASH_SHA1_ALT                      \
-    ASN1_STR_CONSTRUCTED_SEQUENCE "\x1F"        \
-      ASN1_STR_CONSTRUCTED_SEQUENCE "\x07"      \
-        ASN1_STR_OID "\x05"                     \
-      OID_HASH_ALG_SHA1                         \
-      ASN1_STR_OCTET_STRING "\x14"
-
-#define ASN1_HASH_SHA2X                         \
-    ASN1_STR_CONSTRUCTED_SEQUENCE "\x11"        \
-      ASN1_STR_CONSTRUCTED_SEQUENCE "\x0d"      \
-        ASN1_STR_OID "\x09"                     \
-      OID_HASH_ALG_SHA2X                        \
-        ASN1_STR_NULL "\x00"                    \
-      ASN1_STR_OCTET_STRING "\x00"
-
 /**
  * \brief          RSA context structure
  */
@@ -410,8 +336,8 @@
  * \param f_rng    RNG function (Needed for PKCS#1 v2.1 encoding)
  * \param p_rng    RNG parameter
  * \param mode     RSA_PUBLIC or RSA_PRIVATE
- * \param hash_id  SIG_RSA_RAW, SIG_RSA_MD{2,4,5} or SIG_RSA_SHA{1,224,256,384,512}
- * \param hashlen  message digest length (for SIG_RSA_RAW only)
+ * \param md_alg   a POLARSSL_MD_* (use POLARSSL_MD_NONE for signing raw data)
+ * \param hashlen  message digest length (for POLARSSL_MD_NONE only)
  * \param hash     buffer holding the message digest
  * \param sig      buffer that will hold the ciphertext
  *
@@ -431,7 +357,7 @@
                     int (*f_rng)(void *, unsigned char *, size_t),
                     void *p_rng,
                     int mode,
-                    int hash_id,
+                    md_type_t md_alg,
                     unsigned int hashlen,
                     const unsigned char *hash,
                     unsigned char *sig );
@@ -441,8 +367,8 @@
  *
  * \param ctx      RSA context
  * \param mode     RSA_PUBLIC or RSA_PRIVATE
- * \param hash_id  SIG_RSA_RAW, SIG_RSA_MD{2,4,5} or SIG_RSA_SHA{1,224,256,384,512}
- * \param hashlen  message digest length (for SIG_RSA_RAW only)
+ * \param md_alg   a POLARSSL_MD_* (use POLARSSL_MD_NONE for signing raw data)
+ * \param hashlen  message digest length (for POLARSSL_MD_NONE only)
  * \param hash     buffer holding the message digest
  * \param sig      buffer that will hold the ciphertext
  *
@@ -454,7 +380,7 @@
  */
 int rsa_rsassa_pkcs1_v15_sign( rsa_context *ctx,
                                int mode,
-                               int hash_id,
+                               md_type_t md_alg,
                                unsigned int hashlen,
                                const unsigned char *hash,
                                unsigned char *sig );
@@ -466,8 +392,8 @@
  * \param f_rng    RNG function (Needed for PKCS#1 v2.1 encoding)
  * \param p_rng    RNG parameter
  * \param mode     RSA_PUBLIC or RSA_PRIVATE
- * \param hash_id  SIG_RSA_RAW, SIG_RSA_MD{2,4,5} or SIG_RSA_SHA{1,224,256,384,512}
- * \param hashlen  message digest length (for SIG_RSA_RAW only)
+ * \param md_alg   a POLARSSL_MD_* (use POLARSSL_MD_NONE for signing raw data)
+ * \param hashlen  message digest length (for POLARSSL_MD_NONE only)
  * \param hash     buffer holding the message digest
  * \param sig      buffer that will hold the ciphertext
  *
@@ -487,7 +413,7 @@
                          int (*f_rng)(void *, unsigned char *, size_t),
                          void *p_rng,
                          int mode,
-                         int hash_id,
+                         md_type_t md_alg,
                          unsigned int hashlen,
                          const unsigned char *hash,
                          unsigned char *sig );
@@ -499,8 +425,8 @@
  *
  * \param ctx      points to an RSA public key
  * \param mode     RSA_PUBLIC or RSA_PRIVATE
- * \param hash_id  SIG_RSA_RAW, SIG_RSA_MD{2,4,5} or SIG_RSA_SHA{1,224,256,384,512}
- * \param hashlen  message digest length (for SIG_RSA_RAW only)
+ * \param md_alg   a POLARSSL_MD_* (use POLARSSL_MD_NONE for signing raw data)
+ * \param hashlen  message digest length (for POLARSSL_MD_NONE only)
  * \param hash     buffer holding the message digest
  * \param sig      buffer holding the ciphertext
  *
@@ -518,7 +444,7 @@
  */
 int rsa_pkcs1_verify( rsa_context *ctx,
                       int mode,
-                      int hash_id,
+                      md_type_t md_alg,
                       unsigned int hashlen,
                       const unsigned char *hash,
                       unsigned char *sig );
@@ -528,8 +454,8 @@
  *
  * \param ctx      points to an RSA public key
  * \param mode     RSA_PUBLIC or RSA_PRIVATE
- * \param hash_id  SIG_RSA_RAW, SIG_RSA_MD{2,4,5} or SIG_RSA_SHA{1,224,256,384,512}
- * \param hashlen  message digest length (for SIG_RSA_RAW only)
+ * \param md_alg   a POLARSSL_MD_* (use POLARSSL_MD_NONE for signing raw data)
+ * \param hashlen  message digest length (for POLARSSL_MD_NONE only)
  * \param hash     buffer holding the message digest
  * \param sig      buffer holding the ciphertext
  *
@@ -541,7 +467,7 @@
  */
 int rsa_rsassa_pkcs1_v15_verify( rsa_context *ctx,
                                  int mode,
-                                 int hash_id,
+                                 md_type_t md_alg,
                                  unsigned int hashlen,
                                  const unsigned char *hash,
                                  unsigned char *sig );
@@ -552,8 +478,8 @@
  *
  * \param ctx      points to an RSA public key
  * \param mode     RSA_PUBLIC or RSA_PRIVATE
- * \param hash_id  SIG_RSA_RAW, SIG_RSA_MD{2,4,5} or SIG_RSA_SHA{1,224,256,384,512}
- * \param hashlen  message digest length (for SIG_RSA_RAW only)
+ * \param md_alg   a POLARSSL_MD_* (use POLARSSL_MD_NONE for signing raw data)
+ * \param hashlen  message digest length (for POLARSSL_MD_NONE only)
  * \param hash     buffer holding the message digest
  * \param sig      buffer holding the ciphertext
  *
@@ -571,7 +497,7 @@
  */
 int rsa_rsassa_pss_verify( rsa_context *ctx,
                            int mode,
-                           int hash_id,
+                           md_type_t md_alg,
                            unsigned int hashlen,
                            const unsigned char *hash,
                            unsigned char *sig );
diff --git a/include/polarssl/x509.h b/include/polarssl/x509.h
index 87151c9..fe43795 100644
--- a/include/polarssl/x509.h
+++ b/include/polarssl/x509.h
@@ -30,6 +30,7 @@
 #include "asn1.h"
 #include "rsa.h"
 #include "dhm.h"
+#include "md.h"
 
 /** 
  * \addtogroup x509_module
@@ -64,7 +65,6 @@
 #define POLARSSL_ERR_X509_FILE_IO_ERROR                    -0x2B00  /**< Read/write of file failed. */
 /* \} name */
 
-
 /**
  * \name X509 Verify codes
  * \{
@@ -82,69 +82,6 @@
 /* \} addtogroup x509_module */
 
 /*
- * various object identifiers
- */
-#define X520_COMMON_NAME                3
-#define X520_COUNTRY                    6
-#define X520_LOCALITY                   7
-#define X520_STATE                      8
-#define X520_ORGANIZATION              10
-#define X520_ORG_UNIT                  11
-#define PKCS9_EMAIL                     1
-
-#define X509_OUTPUT_DER              0x01
-#define X509_OUTPUT_PEM              0x02
-#define PEM_LINE_LENGTH                72
-#define X509_ISSUER                  0x01
-#define X509_SUBJECT                 0x02
-
-#define OID_X520                "\x55\x04"
-#define OID_CN                  OID_X520 "\x03"
-#define OID_COUNTRY             OID_X520 "\x06"
-#define OID_LOCALITY            OID_X520 "\x07"
-#define OID_STATE               OID_X520 "\x08"
-#define OID_ORGANIZATION        OID_X520 "\x0A"
-#define OID_ORG_UNIT            OID_X520 "\x0B"
-
-#define OID_PKCS1               "\x2A\x86\x48\x86\xF7\x0D\x01\x01"
-#define OID_PKCS1_RSA           OID_PKCS1 "\x01"
-#define OID_PKCS1_SHA1          OID_PKCS1 "\x05"
-
-#define OID_RSA_SHA_OBS         "\x2B\x0E\x03\x02\x1D"
-
-#define OID_PKCS9               "\x2A\x86\x48\x86\xF7\x0D\x01\x09"
-#define OID_PKCS9_EMAIL         OID_PKCS9 "\x01"
-
-/** ISO arc for standard certificate and CRL extensions */
-#define OID_ID_CE               "\x55\x1D" /**< id-ce OBJECT IDENTIFIER  ::=  {joint-iso-ccitt(2) ds(5) 29} */
-
-/**
- * Private Internet Extensions
- * { iso(1) identified-organization(3) dod(6) internet(1)
- *                      security(5) mechanisms(5) pkix(7) }
- */
-#define OID_PKIX                "\x2B\x06\x01\x05\x05\x07"
-
-/*
- * OIDs for standard certificate extensions
- */
-#define OID_AUTHORITY_KEY_IDENTIFIER    OID_ID_CE "\x23" /**< id-ce-authorityKeyIdentifier OBJECT IDENTIFIER ::=  { id-ce 35 } */
-#define OID_SUBJECT_KEY_IDENTIFIER      OID_ID_CE "\x0E" /**< id-ce-subjectKeyIdentifier OBJECT IDENTIFIER ::=  { id-ce 14 } */
-#define OID_KEY_USAGE                   OID_ID_CE "\x0F" /**< id-ce-keyUsage OBJECT IDENTIFIER ::=  { id-ce 15 } */
-#define OID_CERTIFICATE_POLICIES        OID_ID_CE "\x20" /**< id-ce-certificatePolicies OBJECT IDENTIFIER ::=  { id-ce 32 } */
-#define OID_POLICY_MAPPINGS             OID_ID_CE "\x21" /**< id-ce-policyMappings OBJECT IDENTIFIER ::=  { id-ce 33 } */
-#define OID_SUBJECT_ALT_NAME            OID_ID_CE "\x11" /**< id-ce-subjectAltName OBJECT IDENTIFIER ::=  { id-ce 17 } */
-#define OID_ISSUER_ALT_NAME             OID_ID_CE "\x12" /**< id-ce-issuerAltName OBJECT IDENTIFIER ::=  { id-ce 18 } */
-#define OID_SUBJECT_DIRECTORY_ATTRS     OID_ID_CE "\x09" /**< id-ce-subjectDirectoryAttributes OBJECT IDENTIFIER ::=  { id-ce 9 } */
-#define OID_BASIC_CONSTRAINTS           OID_ID_CE "\x13" /**< id-ce-basicConstraints OBJECT IDENTIFIER ::=  { id-ce 19 } */
-#define OID_NAME_CONSTRAINTS            OID_ID_CE "\x1E" /**< id-ce-nameConstraints OBJECT IDENTIFIER ::=  { id-ce 30 } */
-#define OID_POLICY_CONSTRAINTS          OID_ID_CE "\x24" /**< id-ce-policyConstraints OBJECT IDENTIFIER ::=  { id-ce 36 } */
-#define OID_EXTENDED_KEY_USAGE          OID_ID_CE "\x25" /**< id-ce-extKeyUsage OBJECT IDENTIFIER ::= { id-ce 37 } */
-#define OID_CRL_DISTRIBUTION_POINTS     OID_ID_CE "\x1F" /**< id-ce-cRLDistributionPoints OBJECT IDENTIFIER ::=  { id-ce 31 } */
-#define OID_INIHIBIT_ANYPOLICY          OID_ID_CE "\x36" /**< id-ce-inhibitAnyPolicy OBJECT IDENTIFIER ::=  { id-ce 54 } */
-#define OID_FRESHEST_CRL                OID_ID_CE "\x2E" /**< id-ce-freshestCRL OBJECT IDENTIFIER ::=  { id-ce 46 } */
-
-/*
  * X.509 v3 Key Usage Extension flags
  */
 #define KU_DIGITAL_SIGNATURE            (0x80)  /* bit 0 */
@@ -156,48 +93,6 @@
 #define KU_CRL_SIGN                     (0x02)  /* bit 6 */
 
 /*
- * X.509 v3 Extended key usage OIDs
- */
-#define OID_ANY_EXTENDED_KEY_USAGE      OID_EXTENDED_KEY_USAGE "\x00" /**< anyExtendedKeyUsage OBJECT IDENTIFIER ::= { id-ce-extKeyUsage 0 } */
-
-#define OID_KP                          OID_PKIX "\x03" /**< id-kp OBJECT IDENTIFIER ::= { id-pkix 3 } */
-#define OID_SERVER_AUTH                 OID_KP "\x01" /**< id-kp-serverAuth OBJECT IDENTIFIER ::= { id-kp 1 } */
-#define OID_CLIENT_AUTH                 OID_KP "\x02" /**< id-kp-clientAuth OBJECT IDENTIFIER ::= { id-kp 2 } */
-#define OID_CODE_SIGNING                OID_KP "\x03" /**< id-kp-codeSigning OBJECT IDENTIFIER ::= { id-kp 3 } */
-#define OID_EMAIL_PROTECTION            OID_KP "\x04" /**< id-kp-emailProtection OBJECT IDENTIFIER ::= { id-kp 4 } */
-#define OID_TIME_STAMPING               OID_KP "\x08" /**< id-kp-timeStamping OBJECT IDENTIFIER ::= { id-kp 8 } */
-#define OID_OCSP_SIGNING                OID_KP "\x09" /**< id-kp-OCSPSigning OBJECT IDENTIFIER ::= { id-kp 9 } */
-
-#define STRING_SERVER_AUTH              "TLS Web Server Authentication"
-#define STRING_CLIENT_AUTH              "TLS Web Client Authentication"
-#define STRING_CODE_SIGNING             "Code Signing"
-#define STRING_EMAIL_PROTECTION         "E-mail Protection"
-#define STRING_TIME_STAMPING            "Time Stamping"
-#define STRING_OCSP_SIGNING             "OCSP Signing"
-
-/*
- * OIDs for CRL extensions
- */
-#define OID_PRIVATE_KEY_USAGE_PERIOD    OID_ID_CE "\x10"
-#define OID_CRL_NUMBER                  OID_ID_CE "\x14" /**< id-ce-cRLNumber OBJECT IDENTIFIER ::= { id-ce 20 } */
-
-/*
- * Netscape certificate extensions
- */
-#define OID_NETSCAPE                "\x60\x86\x48\x01\x86\xF8\x42" /**< Netscape OID */
-#define OID_NS_CERT                 OID_NETSCAPE "\x01"
-#define OID_NS_CERT_TYPE            OID_NS_CERT  "\x01"
-#define OID_NS_BASE_URL             OID_NS_CERT  "\x02"
-#define OID_NS_REVOCATION_URL       OID_NS_CERT  "\x03"
-#define OID_NS_CA_REVOCATION_URL    OID_NS_CERT  "\x04"
-#define OID_NS_RENEWAL_URL          OID_NS_CERT  "\x07"
-#define OID_NS_CA_POLICY_URL        OID_NS_CERT  "\x08"
-#define OID_NS_SSL_SERVER_NAME      OID_NS_CERT  "\x0C"
-#define OID_NS_COMMENT              OID_NS_CERT  "\x0D"
-#define OID_NS_DATA_TYPE            OID_NETSCAPE "\x02"
-#define OID_NS_CERT_SEQUENCE        OID_NS_DATA_TYPE "\x05"
-
-/*
  * Netscape certificate types
  * (http://www.mozilla.org/projects/security/pki/nss/tech-notes/tn3.html)
  */
@@ -211,6 +106,9 @@
 #define NS_CERT_TYPE_EMAIL_CA           (0x02)  /* bit 6 */
 #define NS_CERT_TYPE_OBJECT_SIGNING_CA  (0x01)  /* bit 7 */
 
+/*
+ * X.509 extension types
+ */
 #define EXT_AUTHORITY_KEY_IDENTIFIER    (1 << 0)
 #define EXT_SUBJECT_KEY_IDENTIFIER      (1 << 1)
 #define EXT_KEY_USAGE                   (1 << 2)
@@ -236,6 +134,12 @@
 #define X509_FORMAT_DER                 1
 #define X509_FORMAT_PEM                 2
 
+typedef enum {
+    POLARSSL_PK_NONE=0,
+    POLARSSL_PK_RSA,
+    POLARSSL_PK_ECDSA,
+} pk_type_t;
+
 /** 
  * \addtogroup x509_module
  * \{ */
@@ -321,7 +225,8 @@
 
     x509_buf sig_oid2;          /**< Signature algorithm. Must match sig_oid1. */
     x509_buf sig;               /**< Signature: hash of the tbs part signed with the private key. */
-    int sig_alg;                /**< Internal representation of the signature algorithm, e.g. SIG_RSA_MD2 */
+    md_type_t sig_md;           /**< Internal representation of the MD algorithm of the signature algorithm, e.g. POLARSSL_MD_SHA256 */
+    pk_type_t sig_pk            /**< Internal representation of the Public Key algorithm of the signature algorithm, e.g. POLARSSL_PK_RSA */;
 
     struct _x509_cert *next;    /**< Next certificate in the CA-chain. */ 
 }
@@ -370,7 +275,8 @@
 
     x509_buf sig_oid2;
     x509_buf sig;
-    int sig_alg;
+    md_type_t sig_md;           /**< Internal representation of the MD algorithm of the signature algorithm, e.g. POLARSSL_MD_SHA256 */
+    pk_type_t sig_pk            /**< Internal representation of the Public Key algorithm of the signature algorithm, e.g. POLARSSL_PK_RSA */;
 
     struct _x509_crl *next; 
 }
diff --git a/include/polarssl/x509write.h b/include/polarssl/x509write.h
index 8ce3d86..9d43efb 100644
--- a/include/polarssl/x509write.h
+++ b/include/polarssl/x509write.h
@@ -41,6 +41,6 @@
 int x509_write_pubkey_der( unsigned char *buf, size_t size, rsa_context *rsa );
 int x509_write_key_der( unsigned char *buf, size_t size, rsa_context *rsa );
 int x509_write_cert_req( unsigned char *buf, size_t size, rsa_context *rsa,
-                         x509_req_name *req_name, int hash_id );
+                         x509_req_name *req_name, md_type_t md_alg );
 
 #endif /* POLARSSL_X509_WRITE_H */