pem.h

00001 /**
00002  * \file pem.h
00003  *
00004  * \brief Privacy Enhanced Mail (PEM) decoding
00005  *
00006  *  Copyright (C) 2006-2013, Brainspark B.V.
00007  *
00008  *  This file is part of PolarSSL (http://www.polarssl.org)
00009  *  Lead Maintainer: Paul Bakker <polarssl_maintainer at polarssl.org>
00010  *
00011  *  All rights reserved.
00012  *
00013  *  This program is free software; you can redistribute it and/or modify
00014  *  it under the terms of the GNU General Public License as published by
00015  *  the Free Software Foundation; either version 2 of the License, or
00016  *  (at your option) any later version.
00017  *
00018  *  This program is distributed in the hope that it will be useful,
00019  *  but WITHOUT ANY WARRANTY; without even the implied warranty of
00020  *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
00021  *  GNU General Public License for more details.
00022  *
00023  *  You should have received a copy of the GNU General Public License along
00024  *  with this program; if not, write to the Free Software Foundation, Inc.,
00025  *  51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
00026  */
00027 #ifndef POLARSSL_PEM_H
00028 #define POLARSSL_PEM_H
00029 
00030 #include <string.h>
00031 
00032 /**
00033  * \name PEM Error codes
00034  * These error codes are returned in case of errors reading the
00035  * PEM data.
00036  * \{
00037  */
00038 #define POLARSSL_ERR_PEM_NO_HEADER_FOOTER_PRESENT          -0x1080  /**< No PEM header or footer found. */
00039 #define POLARSSL_ERR_PEM_INVALID_DATA                      -0x1100  /**< PEM string is not as expected. */
00040 #define POLARSSL_ERR_PEM_MALLOC_FAILED                     -0x1180  /**< Failed to allocate memory. */
00041 #define POLARSSL_ERR_PEM_INVALID_ENC_IV                    -0x1200  /**< RSA IV is not in hex-format. */
00042 #define POLARSSL_ERR_PEM_UNKNOWN_ENC_ALG                   -0x1280  /**< Unsupported key encryption algorithm. */
00043 #define POLARSSL_ERR_PEM_PASSWORD_REQUIRED                 -0x1300  /**< Private key password can't be empty. */
00044 #define POLARSSL_ERR_PEM_PASSWORD_MISMATCH                 -0x1380  /**< Given private key password does not allow for correct decryption. */
00045 #define POLARSSL_ERR_PEM_FEATURE_UNAVAILABLE               -0x1400  /**< Unavailable feature, e.g. hashing/encryption combination. */
00046 #define POLARSSL_ERR_PEM_BAD_INPUT_DATA                    -0x1480  /**< Bad input parameters to function. */
00047 /* \} name */
00048 
00049 #ifdef __cplusplus
00050 extern "C" {
00051 #endif
00052 
00053 #if defined(POLARSSL_PEM_PARSE_C)
00054 /**
00055  * \brief       PEM context structure
00056  */
00057 typedef struct
00058 {
00059     unsigned char *buf ;     /*!< buffer for decoded data             */
00060     size_t buflen ;          /*!< length of the buffer                */
00061     unsigned char *info ;    /*!< buffer for extra header information */
00062 }
00063 pem_context;
00064 
00065 /**
00066  * \brief       PEM context setup
00067  *
00068  * \param ctx   context to be initialized
00069  */
00070 void pem_init( pem_context *ctx );
00071 
00072 /**
00073  * \brief       Read a buffer for PEM information and store the resulting
00074  *              data into the specified context buffers.
00075  *
00076  * \param ctx       context to use
00077  * \param header    header string to seek and expect
00078  * \param footer    footer string to seek and expect
00079  * \param data      source data to look in
00080  * \param pwd       password for decryption (can be NULL)
00081  * \param pwdlen    length of password
00082  * \param use_len   destination for total length used (set after header is
00083  *                  correctly read, so unless you get
00084  *                  POLARSSL_ERR_PEM_BAD_INPUT_DATA or
00085  *                  POLARSSL_ERR_PEM_NO_HEADER_FOOTER_PRESENT, use_len is
00086  *                  the length to skip)
00087  *
00088  * \note            Attempts to check password correctness by verifying if
00089  *                  the decrypted text starts with an ASN.1 sequence of
00090  *                  appropriate length
00091  *
00092  * \return          0 on success, or a specific PEM error code
00093  */
00094 int pem_read_buffer( pem_context *ctx, const char *header, const char *footer,
00095                      const unsigned char *data,
00096                      const unsigned char *pwd,
00097                      size_t pwdlen, size_t *use_len );
00098 
00099 /**
00100  * \brief       PEM context memory freeing
00101  *
00102  * \param ctx   context to be freed
00103  */
00104 void pem_free( pem_context *ctx );
00105 #endif /* POLARSSL_PEM_PARSE_C */
00106 
00107 #if defined(POLARSSL_PEM_WRITE_C)
00108 /**
00109  * \brief           Write a buffer of PEM information from a DER encoded
00110  *                  buffer.
00111  *
00112  * \param header    header string to write
00113  * \param footer    footer string to write
00114  * \param der_data  DER data to write
00115  * \param der_len   length of the DER data
00116  * \param buf       buffer to write to
00117  * \param buf_len   length of output buffer
00118  * \param olen      total length written / required (if buf_len is not enough)
00119  *
00120  * \return          0 on success, or a specific PEM or BASE64 error code. On
00121  *                  POLARSSL_ERR_BASE64_BUFFER_TOO_SMALL olen is the required
00122  *                  size.
00123  */
00124 int pem_write_buffer( const char *header, const char *footer,
00125                       const unsigned char *der_data, size_t der_len,
00126                       unsigned char *buf, size_t buf_len, size_t *olen );
00127 #endif /* POLARSSL_PEM_WRITE_C */
00128 
00129 #ifdef __cplusplus
00130 }
00131 #endif
00132 
00133 #endif /* pem.h */
00134 
00135