diff --git a/include/polarssl/aes.h b/include/polarssl/aes.h
index 4b97568..7404e4e 100644
--- a/include/polarssl/aes.h
+++ b/include/polarssl/aes.h
@@ -32,8 +32,8 @@
 #define AES_ENCRYPT     1
 #define AES_DECRYPT     0
 
-#define POLARSSL_ERR_AES_INVALID_KEY_LENGTH                 -0x0800
-#define POLARSSL_ERR_AES_INVALID_INPUT_LENGTH               -0x0810
+#define POLARSSL_ERR_AES_INVALID_KEY_LENGTH                -0x0020  /**< Invalid key length. */
+#define POLARSSL_ERR_AES_INVALID_INPUT_LENGTH              -0x0022  /**< Invalid data input length. */
 
 /**
  * \brief          AES context structure
diff --git a/include/polarssl/base64.h b/include/polarssl/base64.h
index 27ba685..9071155 100644
--- a/include/polarssl/base64.h
+++ b/include/polarssl/base64.h
@@ -29,8 +29,8 @@
 
 #include <string.h>
 
-#define POLARSSL_ERR_BASE64_BUFFER_TOO_SMALL               0x0010
-#define POLARSSL_ERR_BASE64_INVALID_CHARACTER              0x0012
+#define POLARSSL_ERR_BASE64_BUFFER_TOO_SMALL               -0x0010  /**< Output buffer too small. */
+#define POLARSSL_ERR_BASE64_INVALID_CHARACTER              -0x0012  /**< Invalid character in input. */
 
 #ifdef __cplusplus
 extern "C" {
diff --git a/include/polarssl/bignum.h b/include/polarssl/bignum.h
index 3800967..96b0391 100644
--- a/include/polarssl/bignum.h
+++ b/include/polarssl/bignum.h
@@ -30,13 +30,13 @@
 #include <stdio.h>
 #include <string.h>
 
-#define POLARSSL_ERR_MPI_FILE_IO_ERROR                     0x0002
-#define POLARSSL_ERR_MPI_BAD_INPUT_DATA                    0x0004
-#define POLARSSL_ERR_MPI_INVALID_CHARACTER                 0x0006
-#define POLARSSL_ERR_MPI_BUFFER_TOO_SMALL                  0x0008
-#define POLARSSL_ERR_MPI_NEGATIVE_VALUE                    0x000A
-#define POLARSSL_ERR_MPI_DIVISION_BY_ZERO                  0x000C
-#define POLARSSL_ERR_MPI_NOT_ACCEPTABLE                    0x000E
+#define POLARSSL_ERR_MPI_FILE_IO_ERROR                     -0x0002  /**< An error occurred while reading from or writing to a file. */
+#define POLARSSL_ERR_MPI_BAD_INPUT_DATA                    -0x0004  /**< Bad input parameters to function. */
+#define POLARSSL_ERR_MPI_INVALID_CHARACTER                 -0x0006  /**< There is an invalid character in the digit string. */
+#define POLARSSL_ERR_MPI_BUFFER_TOO_SMALL                  -0x0008  /**< The output buffer is too small to write too. */
+#define POLARSSL_ERR_MPI_NEGATIVE_VALUE                    -0x000A  /**< The input arguments are negative or result in illegal output. */
+#define POLARSSL_ERR_MPI_DIVISION_BY_ZERO                  -0x000C  /**< The input argument for division is zero, which is not allowed. */
+#define POLARSSL_ERR_MPI_NOT_ACCEPTABLE                    -0x000E  /**< The input arguments are not acceptable. */
 
 #define MPI_CHK(f) if( ( ret = f ) != 0 ) goto cleanup
 
diff --git a/include/polarssl/camellia.h b/include/polarssl/camellia.h
index 4884fdc..0dcb830 100644
--- a/include/polarssl/camellia.h
+++ b/include/polarssl/camellia.h
@@ -39,8 +39,8 @@
 #define CAMELLIA_ENCRYPT     1
 #define CAMELLIA_DECRYPT     0
 
-#define POLARSSL_ERR_CAMELLIA_INVALID_KEY_LENGTH            -0x0a00
-#define POLARSSL_ERR_CAMELLIA_INVALID_INPUT_LENGTH          -0x0a10
+#define POLARSSL_ERR_CAMELLIA_INVALID_KEY_LENGTH           -0x0024  /**< Invalid key length. */
+#define POLARSSL_ERR_CAMELLIA_INVALID_INPUT_LENGTH         -0x0026  /**< Invalid data input length. */
 
 /**
  * \brief          CAMELLIA context structure
diff --git a/include/polarssl/config.h b/include/polarssl/config.h
index cf3eb9a..d063e83 100644
--- a/include/polarssl/config.h
+++ b/include/polarssl/config.h
@@ -324,6 +324,18 @@
 #define POLARSSL_DHM_C
 
 /**
+ * \def POLARSSL_ERROR_C
+ *
+ * Enable error code to error string conversion.
+ *
+ * Module:  library/error.c
+ * Caller:
+ *
+ * This module enables err_strerror().
+ */
+#define POLARSSL_ERROR_C
+
+/**
  * \def POLARSSL_HAVEGE_C
  *
  * Enable the HAVEGE random generator.
diff --git a/include/polarssl/des.h b/include/polarssl/des.h
index f9e8e60..5606afb 100644
--- a/include/polarssl/des.h
+++ b/include/polarssl/des.h
@@ -32,7 +32,7 @@
 #define DES_ENCRYPT     1
 #define DES_DECRYPT     0
 
-#define POLARSSL_ERR_DES_INVALID_INPUT_LENGTH               -0x0C00
+#define POLARSSL_ERR_DES_INVALID_INPUT_LENGTH              -0x0032  /**< The data input has an invalid length. */
 
 #define DES_KEY_SIZE    8
 
diff --git a/include/polarssl/dhm.h b/include/polarssl/dhm.h
index 4a479d6..94ad015 100644
--- a/include/polarssl/dhm.h
+++ b/include/polarssl/dhm.h
@@ -32,12 +32,12 @@
 /*
  * DHM Error codes
  */
-#define POLARSSL_ERR_DHM_BAD_INPUT_DATA                    0x0480
-#define POLARSSL_ERR_DHM_READ_PARAMS_FAILED                0x0490
-#define POLARSSL_ERR_DHM_MAKE_PARAMS_FAILED                0x04A0
-#define POLARSSL_ERR_DHM_READ_PUBLIC_FAILED                0x04B0
-#define POLARSSL_ERR_DHM_MAKE_PUBLIC_FAILED                0x04C0
-#define POLARSSL_ERR_DHM_CALC_SECRET_FAILED                0x04D0
+#define POLARSSL_ERR_DHM_BAD_INPUT_DATA                    -0x3080  /**< Bad input parameters to function. */
+#define POLARSSL_ERR_DHM_READ_PARAMS_FAILED                -0x3100  /**< Reading of the DHM parameters failed. */
+#define POLARSSL_ERR_DHM_MAKE_PARAMS_FAILED                -0x3180  /**< Making of the DHM parameters failed. */
+#define POLARSSL_ERR_DHM_READ_PUBLIC_FAILED                -0x3200  /**< Reading of the public values failed. */
+#define POLARSSL_ERR_DHM_MAKE_PUBLIC_FAILED                -0x3280  /**< Makeing of the public value failed. */
+#define POLARSSL_ERR_DHM_CALC_SECRET_FAILED                -0x3300  /**< Calculation of the DHM secret failed. */
 
 /**
  * \brief          DHM context structure
diff --git a/include/polarssl/error.h b/include/polarssl/error.h
new file mode 100644
index 0000000..b9a73af
--- /dev/null
+++ b/include/polarssl/error.h
@@ -0,0 +1,85 @@
+/**
+ * \file error.h
+ *
+ * \brief Error to string translation
+ *
+ *  Copyright (C) 2006-2010, 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_ERROR_H
+#define POLARSSL_ERROR_H
+
+/**
+ * Error code layout.
+ *
+ * Currently we try to keep all error codes within the negative space of 16
+ * bytes signed integers to support all platforms (-0x0000 - -0x8000). In
+ * addition we'd like to give two layers of information on the error if
+ * possible.
+ *
+ * For that purpose the error codes are segmented in the following manner:
+ *
+ * 16 bit error code bit-segmentation
+ *
+ * 1 bit  - Intentionally not used
+ * 3 bits - High level module ID
+ * 5 bits - Module-dependent error code
+ * 6 bits - Low level module errors
+ * 1 bit  - Intentionally not used
+ *
+ * Low-level module errors (0x007E-0x0002)
+ *
+ * Module   Nr  Codes assigned 
+ * MPI       7  0x0002-0x000E
+ * BASE64    2  0x0010-0x0012
+ * ASN1      5  0x0014-0x001C
+ * AES       2  0x0020-0x0022
+ * CAMELLIA  2  0x0024-0x0026
+ * XTEA      1  0x0028-0x0028
+ * PADLOCK   1  0x0030-0x0030
+ * DES       1  0x0032-0x0032
+ * NET      10  0x0040-0x0052
+ *
+ * High-level module nr (3 bits - 0x1...-0x8...)
+ * Name     ID  Nr of Errors
+ * PEM      1   8
+ * X509     2   20
+ * DHM      3   6
+ * RSA      4   9
+ * MD       5   1
+ * CIPER    6   1
+ * SSL      7   27
+ *
+ * Module dependent error code (5 bits 0x.08.-0x.F8.)
+ */
+
+/**
+ * \brief Translate a PolarSSL error code into a string representation,
+ *        Result is truncated if necessary and always includes a terminating
+ *        null byte.
+ *
+ * \param errnum    error code
+ * \param buffer    buffer to place representation in
+ * \param buflen    length of the buffer
+ */
+void error_strerror( int errnum, char *buffer, size_t buflen );
+
+#endif /* error.h */
diff --git a/include/polarssl/md.h b/include/polarssl/md.h
index 57a0d6a..7914d88 100644
--- a/include/polarssl/md.h
+++ b/include/polarssl/md.h
@@ -36,7 +36,7 @@
 #define inline _inline
 #endif
 
-#define POLARSSL_ERR_MD_FEATURE_UNAVAILABLE                     -0x0830
+#define POLARSSL_ERR_MD_FEATURE_UNAVAILABLE                -0x5080  /**< The selected feature is not available. */
 
 typedef enum {
     POLARSSL_MD_NONE=0,
diff --git a/include/polarssl/net.h b/include/polarssl/net.h
index 3fa2161..d828a3e 100644
--- a/include/polarssl/net.h
+++ b/include/polarssl/net.h
@@ -29,16 +29,16 @@
 
 #include <string.h>
 
-#define POLARSSL_ERR_NET_UNKNOWN_HOST                      -0x0F00
-#define POLARSSL_ERR_NET_SOCKET_FAILED                     -0x0F10
-#define POLARSSL_ERR_NET_CONNECT_FAILED                    -0x0F20
-#define POLARSSL_ERR_NET_BIND_FAILED                       -0x0F30
-#define POLARSSL_ERR_NET_LISTEN_FAILED                     -0x0F40
-#define POLARSSL_ERR_NET_ACCEPT_FAILED                     -0x0F50
-#define POLARSSL_ERR_NET_RECV_FAILED                       -0x0F60
-#define POLARSSL_ERR_NET_SEND_FAILED                       -0x0F70
-#define POLARSSL_ERR_NET_CONN_RESET                        -0x0F80
-#define POLARSSL_ERR_NET_TRY_AGAIN                         -0x0F90
+#define POLARSSL_ERR_NET_UNKNOWN_HOST                      -0x0040  /**< Failed to get an IP address for the given hostname. */
+#define POLARSSL_ERR_NET_SOCKET_FAILED                     -0x0042  /**< Failed to open a socket. */
+#define POLARSSL_ERR_NET_CONNECT_FAILED                    -0x0044  /**< The connection to the given server / port failed. */
+#define POLARSSL_ERR_NET_BIND_FAILED                       -0x0046  /**< Binding of the socket failed. */
+#define POLARSSL_ERR_NET_LISTEN_FAILED                     -0x0048  /**< Could not listen on the socket. */
+#define POLARSSL_ERR_NET_ACCEPT_FAILED                     -0x004A  /**< Could not accept the incoming connection. */
+#define POLARSSL_ERR_NET_RECV_FAILED                       -0x004C  /**< Reading information from the socket failed. */
+#define POLARSSL_ERR_NET_SEND_FAILED                       -0x004E  /**< Sending information through the socket failed. */
+#define POLARSSL_ERR_NET_CONN_RESET                        -0x0050  /**< Connection was reset by peer. */
+#define POLARSSL_ERR_NET_TRY_AGAIN                         -0x0052  /**< Connection was busy, try again. */
 
 #ifdef __cplusplus
 extern "C" {
diff --git a/include/polarssl/padlock.h b/include/polarssl/padlock.h
index 722c9b2..6a0bda2 100644
--- a/include/polarssl/padlock.h
+++ b/include/polarssl/padlock.h
@@ -42,7 +42,7 @@
 
 #define PADLOCK_ALIGN16(x) (unsigned long *) (16 + ((long) x & ~15))
 
-#define POLARSSL_ERR_PADLOCK_DATA_MISALIGNED                    -0x08E0
+#define POLARSSL_ERR_PADLOCK_DATA_MISALIGNED               -0x0030  /**< Input data should be aligned. */
 
 #ifdef __cplusplus
 extern "C" {
diff --git a/include/polarssl/pem.h b/include/polarssl/pem.h
index 509ed11..1505401 100644
--- a/include/polarssl/pem.h
+++ b/include/polarssl/pem.h
@@ -35,14 +35,14 @@
  * PEM data.
  * \{
  */
-#define POLARSSL_ERR_PEM_NO_HEADER_PRESENT                 -0x0500  /**< No PEM header found. */
-#define POLARSSL_ERR_PEM_INVALID_DATA                      -0x0520  /**< PEM string is not as expected. */
-#define POLARSSL_ERR_PEM_MALLOC_FAILED                     -0x0540  /**< Failed to allocate memory. */
-#define POLARSSL_ERR_PEM_INVALID_ENC_IV                    -0x0560  /**< RSA IV is not in hex-format. */
-#define POLARSSL_ERR_PEM_UNKNOWN_ENC_ALG                   -0x0580  /**< Unsupported key encryption algorithm. */
-#define POLARSSL_ERR_PEM_PASSWORD_REQUIRED                 -0x05A0  /**< Private key password can't be empty. */
-#define POLARSSL_ERR_PEM_PASSWORD_MISMATCH                 -0x05C0  /**< Given private key password does not allow for correct decryption. */
-#define POLARSSL_ERR_PEM_FEATURE_UNAVAILABLE               -0x05E0  /**< Unavailable feature, e.g. hashing/encryption combination. */
+#define POLARSSL_ERR_PEM_NO_HEADER_PRESENT                 -0x1080  /**< No PEM header found. */
+#define POLARSSL_ERR_PEM_INVALID_DATA                      -0x1100  /**< PEM string is not as expected. */
+#define POLARSSL_ERR_PEM_MALLOC_FAILED                     -0x1180  /**< Failed to allocate memory. */
+#define POLARSSL_ERR_PEM_INVALID_ENC_IV                    -0x1200  /**< RSA IV is not in hex-format. */
+#define POLARSSL_ERR_PEM_UNKNOWN_ENC_ALG                   -0x1280  /**< Unsupported key encryption algorithm. */
+#define POLARSSL_ERR_PEM_PASSWORD_REQUIRED                 -0x1300  /**< Private key password can't be empty. */
+#define POLARSSL_ERR_PEM_PASSWORD_MISMATCH                 -0x1380  /**< Given private key password does not allow for correct decryption. */
+#define POLARSSL_ERR_PEM_FEATURE_UNAVAILABLE               -0x1400  /**< Unavailable feature, e.g. hashing/encryption combination. */
 /* \} name */
 
 /**
diff --git a/include/polarssl/rsa.h b/include/polarssl/rsa.h
index cb2420a..441c998 100644
--- a/include/polarssl/rsa.h
+++ b/include/polarssl/rsa.h
@@ -32,15 +32,15 @@
 /*
  * RSA Error codes
  */
-#define POLARSSL_ERR_RSA_BAD_INPUT_DATA                    -0x0400
-#define POLARSSL_ERR_RSA_INVALID_PADDING                   -0x0410
-#define POLARSSL_ERR_RSA_KEY_GEN_FAILED                    -0x0420
-#define POLARSSL_ERR_RSA_KEY_CHECK_FAILED                  -0x0430
-#define POLARSSL_ERR_RSA_PUBLIC_FAILED                     -0x0440
-#define POLARSSL_ERR_RSA_PRIVATE_FAILED                    -0x0450
-#define POLARSSL_ERR_RSA_VERIFY_FAILED                     -0x0460
-#define POLARSSL_ERR_RSA_OUTPUT_TOO_LARGE                  -0x0470
-#define POLARSSL_ERR_RSA_RNG_FAILED                        -0x0480
+#define POLARSSL_ERR_RSA_BAD_INPUT_DATA                    -0x4080  /**< Bad input parameters to function. */
+#define POLARSSL_ERR_RSA_INVALID_PADDING                   -0x4100  /**< Input data contains invalid padding and is rejected. */
+#define POLARSSL_ERR_RSA_KEY_GEN_FAILED                    -0x4180  /**< Something failed during generation of a key. */
+#define POLARSSL_ERR_RSA_KEY_CHECK_FAILED                  -0x4200  /**< Key failed to pass the libraries validity check. */
+#define POLARSSL_ERR_RSA_PUBLIC_FAILED                     -0x4280  /**< The public key operation failed. */
+#define POLARSSL_ERR_RSA_PRIVATE_FAILED                    -0x4300  /**< The private key operation failed. */
+#define POLARSSL_ERR_RSA_VERIFY_FAILED                     -0x4380  /**< The PKCS#1 verification failed. */
+#define POLARSSL_ERR_RSA_OUTPUT_TOO_LARGE                  -0x4400  /**< The output buffer for decryption is not large enough. */
+#define POLARSSL_ERR_RSA_RNG_FAILED                        -0x4480  /**< The random generator failed to generate non-zeros. */
 
 /*
  * PKCS#1 constants
diff --git a/include/polarssl/ssl.h b/include/polarssl/ssl.h
index 15b595f..af9ec11 100644
--- a/include/polarssl/ssl.h
+++ b/include/polarssl/ssl.h
@@ -48,33 +48,35 @@
 /*
  * SSL Error codes
  */
-#define POLARSSL_ERR_SSL_FEATURE_UNAVAILABLE               -0x1000
-#define POLARSSL_ERR_SSL_BAD_INPUT_DATA                    -0x1800
-#define POLARSSL_ERR_SSL_INVALID_MAC                       -0x2000
-#define POLARSSL_ERR_SSL_INVALID_RECORD                    -0x2800
-#define POLARSSL_ERR_SSL_INVALID_MODULUS_SIZE              -0x3000
-#define POLARSSL_ERR_SSL_UNKNOWN_CIPHER                    -0x3800
-#define POLARSSL_ERR_SSL_NO_CIPHER_CHOSEN                  -0x4000
-#define POLARSSL_ERR_SSL_NO_SESSION_FOUND                  -0x4800
-#define POLARSSL_ERR_SSL_NO_CLIENT_CERTIFICATE             -0x5000
-#define POLARSSL_ERR_SSL_CERTIFICATE_TOO_LARGE             -0x5800
-#define POLARSSL_ERR_SSL_CERTIFICATE_REQUIRED              -0x6000
-#define POLARSSL_ERR_SSL_PRIVATE_KEY_REQUIRED              -0x6800
-#define POLARSSL_ERR_SSL_CA_CHAIN_REQUIRED                 -0x7000
-#define POLARSSL_ERR_SSL_UNEXPECTED_MESSAGE                -0x7800
-#define POLARSSL_ERR_SSL_FATAL_ALERT_MESSAGE               -0x8000
-#define POLARSSL_ERR_SSL_PEER_VERIFY_FAILED                -0x8800
-#define POLARSSL_ERR_SSL_PEER_CLOSE_NOTIFY                 -0x9000
-#define POLARSSL_ERR_SSL_BAD_HS_CLIENT_HELLO               -0x9800
-#define POLARSSL_ERR_SSL_BAD_HS_SERVER_HELLO               -0xA000
-#define POLARSSL_ERR_SSL_BAD_HS_CERTIFICATE                -0xA800
-#define POLARSSL_ERR_SSL_BAD_HS_CERTIFICATE_REQUEST        -0xB000
-#define POLARSSL_ERR_SSL_BAD_HS_SERVER_KEY_EXCHANGE        -0xB800
-#define POLARSSL_ERR_SSL_BAD_HS_SERVER_HELLO_DONE          -0xC000
-#define POLARSSL_ERR_SSL_BAD_HS_CLIENT_KEY_EXCHANGE        -0xC800
-#define POLARSSL_ERR_SSL_BAD_HS_CERTIFICATE_VERIFY         -0xD000
-#define POLARSSL_ERR_SSL_BAD_HS_CHANGE_CIPHER_SPEC         -0xD800
-#define POLARSSL_ERR_SSL_BAD_HS_FINISHED                   -0xE000
+#define POLARSSL_ERR_SSL_FEATURE_UNAVAILABLE               -0x7080  /**< The requested feature is not available. */
+#define POLARSSL_ERR_SSL_BAD_INPUT_DATA                    -0x7100  /**< Bad input parameters to function. */
+#define POLARSSL_ERR_SSL_INVALID_MAC                       -0x7180  /**< Verification of the message MAC failed. */
+#define POLARSSL_ERR_SSL_INVALID_RECORD                    -0x7200  /**< An invalid SSL record was received. */
+#define POLARSSL_ERR_SSL_INVALID_MODULUS_SIZE              -0x7280  /**< An invalid modulus size was received. */
+#define POLARSSL_ERR_SSL_UNKNOWN_CIPHER                    -0x7300  /**< An unknown cipher was received. */
+#define POLARSSL_ERR_SSL_NO_CIPHER_CHOSEN                  -0x7380  /**< The server has no ciphersuites in common with the client. */
+#define POLARSSL_ERR_SSL_NO_SESSION_FOUND                  -0x7400  /**< No session to recover was found. */
+#define POLARSSL_ERR_SSL_NO_CLIENT_CERTIFICATE             -0x7480  /**< No client certification received from the client, but required by the authentication mode. */
+#define POLARSSL_ERR_SSL_CERTIFICATE_TOO_LARGE             -0x7500  /**< Our own certificate(s) is/are too large to send in an SSL message.*/
+#define POLARSSL_ERR_SSL_CERTIFICATE_REQUIRED              -0x7580  /**< The own certificate is not set, but needed by the server. */
+#define POLARSSL_ERR_SSL_PRIVATE_KEY_REQUIRED              -0x7600  /**< The own private key is not set, but needed. */
+#define POLARSSL_ERR_SSL_CA_CHAIN_REQUIRED                 -0x7680  /**< No CA Chain is set, but required to operate. */
+#define POLARSSL_ERR_SSL_UNEXPECTED_MESSAGE                -0x7700  /**< An unexpected message was received from our peer. */
+#define POLARSSL_ERR_SSL_FATAL_ALERT_MESSAGE               -0x7780  /**< A fatal alert message was received from our peer. */
+#define POLARSSL_ERR_SSL_PEER_VERIFY_FAILED                -0x7800  /**< Verification of our peer failed. */
+#define POLARSSL_ERR_SSL_PEER_CLOSE_NOTIFY                 -0x7880  /**< The peer notified us that the connection is going to be closed. */
+#define POLARSSL_ERR_SSL_BAD_HS_CLIENT_HELLO               -0x7900  /**< Processing of the ClientHello handshake message failed. */
+#define POLARSSL_ERR_SSL_BAD_HS_SERVER_HELLO               -0x7980  /**< Processing of the ServerHello handshake message failed. */
+#define POLARSSL_ERR_SSL_BAD_HS_CERTIFICATE                -0x7A00  /**< Processing of the Certificate handshake message failed. */
+#define POLARSSL_ERR_SSL_BAD_HS_CERTIFICATE_REQUEST        -0x7A80  /**< Processing of the CertificateRequest handshake message failed. */
+#define POLARSSL_ERR_SSL_BAD_HS_SERVER_KEY_EXCHANGE        -0x7B00  /**< Processing of the ServerKeyExchange handshake message failed. */
+#define POLARSSL_ERR_SSL_BAD_HS_SERVER_HELLO_DONE          -0x7B80  /**< Processing of the ServerHelloDone handshake message failed. */
+#define POLARSSL_ERR_SSL_BAD_HS_CLIENT_KEY_EXCHANGE        -0x7C00  /**< Processing of the ClientKeyExchange handshake message failed. */
+#define POLARSSL_ERR_SSL_BAD_HS_CLIENT_KEY_EXCHANGE_DHM_RP -0x7C80  /**< Processing of the ClientKeyExchange handshake message failed in DHM Read Public. */
+#define POLARSSL_ERR_SSL_BAD_HS_CLIENT_KEY_EXCHANGE_DHM_CS -0x7D00  /**< Processing of the ClientKeyExchange handshake message failed in DHM Calculate Secret. */
+#define POLARSSL_ERR_SSL_BAD_HS_CERTIFICATE_VERIFY         -0x7D80  /**< Processing of the CertificateVerify handshake message failed. */
+#define POLARSSL_ERR_SSL_BAD_HS_CHANGE_CIPHER_SPEC         -0x7E00  /**< Processing of the ChangeCipherSpec handshake message failed. */
+#define POLARSSL_ERR_SSL_BAD_HS_FINISHED                   -0x7E80  /**< Processing of the Finished handshake message failed. */
 
 /*
  * Various constants
diff --git a/include/polarssl/x509.h b/include/polarssl/x509.h
index 731c186..9ce98f4 100644
--- a/include/polarssl/x509.h
+++ b/include/polarssl/x509.h
@@ -42,37 +42,37 @@
  * ASN1 is a standard to specify data structures.
  * \{
  */
-#define POLARSSL_ERR_ASN1_OUT_OF_DATA                      0x0014   /**< Out of data when parsing an ASN1 data structure. */
-#define POLARSSL_ERR_ASN1_UNEXPECTED_TAG                   0x0016   /**< ASN1 tag was of an unexpected value. */
-#define POLARSSL_ERR_ASN1_INVALID_LENGTH                   0x0018   /**< Error when trying to determine the length or invalid length. */
-#define POLARSSL_ERR_ASN1_LENGTH_MISMATCH                  0x001A   /**< Actual length differs from expected length. */
-#define POLARSSL_ERR_ASN1_INVALID_DATA                     0x001C   /**< Data is invalid. (not used) */
+#define POLARSSL_ERR_ASN1_OUT_OF_DATA                      -0x0014  /**< Out of data when parsing an ASN1 data structure. */
+#define POLARSSL_ERR_ASN1_UNEXPECTED_TAG                   -0x0016  /**< ASN1 tag was of an unexpected value. */
+#define POLARSSL_ERR_ASN1_INVALID_LENGTH                   -0x0018  /**< Error when trying to determine the length or invalid length. */
+#define POLARSSL_ERR_ASN1_LENGTH_MISMATCH                  -0x001A  /**< Actual length differs from expected length. */
+#define POLARSSL_ERR_ASN1_INVALID_DATA                     -0x001C  /**< Data is invalid. (not used) */
 /* \} name */
 
 /** 
  * \name X509 Error codes
  * \{
  */
-#define POLARSSL_ERR_X509_FEATURE_UNAVAILABLE              -0x0020  /**< Unavailable feature, e.g. RSA hashing/encryption combination. */
-#define POLARSSL_ERR_X509_CERT_INVALID_PEM                 -0x0040  /**< The PEM-encoded certificate contains invalid elements, e.g. invalid character. */ 
-#define POLARSSL_ERR_X509_CERT_INVALID_FORMAT              -0x0060  /**< The certificate format is invalid, e.g. different type expected. */
-#define POLARSSL_ERR_X509_CERT_INVALID_VERSION             -0x0080  /**< The certificate version element is invalid. */
-#define POLARSSL_ERR_X509_CERT_INVALID_SERIAL              -0x00A0  /**< The serial tag or value is invalid. */
-#define POLARSSL_ERR_X509_CERT_INVALID_ALG                 -0x00C0  /**< The algorithm tag or value is invalid. */
-#define POLARSSL_ERR_X509_CERT_INVALID_NAME                -0x00E0  /**< The name tag or value is invalid. */
-#define POLARSSL_ERR_X509_CERT_INVALID_DATE                -0x0100  /**< The date tag or value is invalid. */
-#define POLARSSL_ERR_X509_CERT_INVALID_PUBKEY              -0x0120  /**< The pubkey tag or value is invalid (only RSA is supported). */
-#define POLARSSL_ERR_X509_CERT_INVALID_SIGNATURE           -0x0140  /**< The signature tag or value invalid. */
-#define POLARSSL_ERR_X509_CERT_INVALID_EXTENSIONS          -0x0160  /**< The extension tag or value is invalid. */
-#define POLARSSL_ERR_X509_CERT_UNKNOWN_VERSION             -0x0180  /**< Certificate or CRL has an unsupported version number. */
-#define POLARSSL_ERR_X509_CERT_UNKNOWN_SIG_ALG             -0x01A0  /**< Signature algorithm (oid) is unsupported. */
-#define POLARSSL_ERR_X509_CERT_UNKNOWN_PK_ALG              -0x01C0  /**< Public key algorithm is unsupported (only RSA is supported). */
-#define POLARSSL_ERR_X509_CERT_SIG_MISMATCH                -0x01E0  /**< Certificate signature algorithms do not match. (see \c ::x509_cert sig_oid) */
-#define POLARSSL_ERR_X509_CERT_VERIFY_FAILED               -0x0200  /**< Certificate verification failed, e.g. CRL, CA or signature check failed. */
-#define POLARSSL_ERR_X509_KEY_INVALID_VERSION              -0x0240  /**< Unsupported RSA key version */
-#define POLARSSL_ERR_X509_KEY_INVALID_FORMAT               -0x0260  /**< Invalid RSA key tag or value. */
-#define POLARSSL_ERR_X509_POINT_ERROR                      -0x0300  /**< Not used. */
-#define POLARSSL_ERR_X509_VALUE_TO_LENGTH                  -0x0320  /**< Not used. */
+#define POLARSSL_ERR_X509_FEATURE_UNAVAILABLE              -0x2080  /**< Unavailable feature, e.g. RSA hashing/encryption combination. */
+#define POLARSSL_ERR_X509_CERT_INVALID_PEM                 -0x2100  /**< The PEM-encoded certificate contains invalid elements, e.g. invalid character. */ 
+#define POLARSSL_ERR_X509_CERT_INVALID_FORMAT              -0x2180  /**< The certificate format is invalid, e.g. different type expected. */
+#define POLARSSL_ERR_X509_CERT_INVALID_VERSION             -0x2200  /**< The certificate version element is invalid. */
+#define POLARSSL_ERR_X509_CERT_INVALID_SERIAL              -0x2280  /**< The serial tag or value is invalid. */
+#define POLARSSL_ERR_X509_CERT_INVALID_ALG                 -0x2300  /**< The algorithm tag or value is invalid. */
+#define POLARSSL_ERR_X509_CERT_INVALID_NAME                -0x2380  /**< The name tag or value is invalid. */
+#define POLARSSL_ERR_X509_CERT_INVALID_DATE                -0x2400  /**< The date tag or value is invalid. */
+#define POLARSSL_ERR_X509_CERT_INVALID_PUBKEY              -0x2480  /**< The pubkey tag or value is invalid (only RSA is supported). */
+#define POLARSSL_ERR_X509_CERT_INVALID_SIGNATURE           -0x2500  /**< The signature tag or value invalid. */
+#define POLARSSL_ERR_X509_CERT_INVALID_EXTENSIONS          -0x2580  /**< The extension tag or value is invalid. */
+#define POLARSSL_ERR_X509_CERT_UNKNOWN_VERSION             -0x2600  /**< Certificate or CRL has an unsupported version number. */
+#define POLARSSL_ERR_X509_CERT_UNKNOWN_SIG_ALG             -0x2680  /**< Signature algorithm (oid) is unsupported. */
+#define POLARSSL_ERR_X509_CERT_UNKNOWN_PK_ALG              -0x2700  /**< Public key algorithm is unsupported (only RSA is supported). */
+#define POLARSSL_ERR_X509_CERT_SIG_MISMATCH                -0x2780  /**< Certificate signature algorithms do not match. (see \c ::x509_cert sig_oid) */
+#define POLARSSL_ERR_X509_CERT_VERIFY_FAILED               -0x2800  /**< Certificate verification failed, e.g. CRL, CA or signature check failed. */
+#define POLARSSL_ERR_X509_KEY_INVALID_VERSION              -0x2880  /**< Unsupported RSA key version */
+#define POLARSSL_ERR_X509_KEY_INVALID_FORMAT               -0x2900  /**< Invalid RSA key tag or value. */
+#define POLARSSL_ERR_X509_POINT_ERROR                      -0x2980  /**< Not used. */
+#define POLARSSL_ERR_X509_VALUE_TO_LENGTH                  -0x2A00  /**< Not used. */
 /* \} name */
 
 
diff --git a/include/polarssl/xtea.h b/include/polarssl/xtea.h
index 8f41d5d..e2adb87 100644
--- a/include/polarssl/xtea.h
+++ b/include/polarssl/xtea.h
@@ -39,7 +39,7 @@
 #define XTEA_ENCRYPT     1
 #define XTEA_DECRYPT     0
 
-#define POLARSSL_ERR_XTEA_INVALID_INPUT_LENGTH               -0x0820
+#define POLARSSL_ERR_XTEA_INVALID_INPUT_LENGTH             -0x0028  /**< The data input has an invalid length. */
 
 /**
  * \brief          XTEA context structure