1 /** 2 * \file pem.h 3 * 4 * \brief Privacy Enhanced Mail (PEM) decoding 5 */ 6 /* 7 * Copyright The Mbed TLS Contributors 8 * SPDX-License-Identifier: Apache-2.0 OR GPL-2.0-or-later 9 * 10 * This file is provided under the Apache License 2.0, or the 11 * GNU General Public License v2.0 or later. 12 * 13 * ********** 14 * Apache License 2.0: 15 * 16 * Licensed under the Apache License, Version 2.0 (the "License"); you may 17 * not use this file except in compliance with the License. 18 * You may obtain a copy of the License at 19 * 20 * http://www.apache.org/licenses/LICENSE-2.0 21 * 22 * Unless required by applicable law or agreed to in writing, software 23 * distributed under the License is distributed on an "AS IS" BASIS, WITHOUT 24 * WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. 25 * See the License for the specific language governing permissions and 26 * limitations under the License. 27 * 28 * ********** 29 * 30 * ********** 31 * GNU General Public License v2.0 or later: 32 * 33 * This program is free software; you can redistribute it and/or modify 34 * it under the terms of the GNU General Public License as published by 35 * the Free Software Foundation; either version 2 of the License, or 36 * (at your option) any later version. 37 * 38 * This program is distributed in the hope that it will be useful, 39 * but WITHOUT ANY WARRANTY; without even the implied warranty of 40 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the 41 * GNU General Public License for more details. 42 * 43 * You should have received a copy of the GNU General Public License along 44 * with this program; if not, write to the Free Software Foundation, Inc., 45 * 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA. 46 * 47 * ********** 48 */ 49 #ifndef MBEDTLS_PEM_H 50 #define MBEDTLS_PEM_H 51 52 #if !defined(MBEDTLS_CONFIG_FILE) 53 #include "config.h" 54 #else 55 #include MBEDTLS_CONFIG_FILE 56 #endif 57 58 #include <stddef.h> 59 60 /** 61 * \name PEM Error codes 62 * These error codes are returned in case of errors reading the 63 * PEM data. 64 * \{ 65 */ 66 #define MBEDTLS_ERR_PEM_NO_HEADER_FOOTER_PRESENT -0x1080 /**< No PEM header or footer found. */ 67 #define MBEDTLS_ERR_PEM_INVALID_DATA -0x1100 /**< PEM string is not as expected. */ 68 #define MBEDTLS_ERR_PEM_ALLOC_FAILED -0x1180 /**< Failed to allocate memory. */ 69 #define MBEDTLS_ERR_PEM_INVALID_ENC_IV -0x1200 /**< RSA IV is not in hex-format. */ 70 #define MBEDTLS_ERR_PEM_UNKNOWN_ENC_ALG -0x1280 /**< Unsupported key encryption algorithm. */ 71 #define MBEDTLS_ERR_PEM_PASSWORD_REQUIRED -0x1300 /**< Private key password can't be empty. */ 72 #define MBEDTLS_ERR_PEM_PASSWORD_MISMATCH -0x1380 /**< Given private key password does not allow for correct decryption. */ 73 #define MBEDTLS_ERR_PEM_FEATURE_UNAVAILABLE -0x1400 /**< Unavailable feature, e.g. hashing/encryption combination. */ 74 #define MBEDTLS_ERR_PEM_BAD_INPUT_DATA -0x1480 /**< Bad input parameters to function. */ 75 /* \} name */ 76 77 #ifdef __cplusplus 78 extern "C" { 79 #endif 80 81 #if defined(MBEDTLS_PEM_PARSE_C) 82 /** 83 * \brief PEM context structure 84 */ 85 typedef struct mbedtls_pem_context 86 { 87 unsigned char *buf; /*!< buffer for decoded data */ 88 size_t buflen; /*!< length of the buffer */ 89 unsigned char *info; /*!< buffer for extra header information */ 90 } 91 mbedtls_pem_context; 92 93 /** 94 * \brief PEM context setup 95 * 96 * \param ctx context to be initialized 97 */ 98 void mbedtls_pem_init( mbedtls_pem_context *ctx ); 99 100 /** 101 * \brief Read a buffer for PEM information and store the resulting 102 * data into the specified context buffers. 103 * 104 * \param ctx context to use 105 * \param header header string to seek and expect 106 * \param footer footer string to seek and expect 107 * \param data source data to look in (must be nul-terminated) 108 * \param pwd password for decryption (can be NULL) 109 * \param pwdlen length of password 110 * \param use_len destination for total length used (set after header is 111 * correctly read, so unless you get 112 * MBEDTLS_ERR_PEM_BAD_INPUT_DATA or 113 * MBEDTLS_ERR_PEM_NO_HEADER_FOOTER_PRESENT, use_len is 114 * the length to skip) 115 * 116 * \note Attempts to check password correctness by verifying if 117 * the decrypted text starts with an ASN.1 sequence of 118 * appropriate length 119 * 120 * \return 0 on success, or a specific PEM error code 121 */ 122 int mbedtls_pem_read_buffer( mbedtls_pem_context *ctx, const char *header, const char *footer, 123 const unsigned char *data, 124 const unsigned char *pwd, 125 size_t pwdlen, size_t *use_len ); 126 127 /** 128 * \brief PEM context memory freeing 129 * 130 * \param ctx context to be freed 131 */ 132 void mbedtls_pem_free( mbedtls_pem_context *ctx ); 133 #endif /* MBEDTLS_PEM_PARSE_C */ 134 135 #if defined(MBEDTLS_PEM_WRITE_C) 136 /** 137 * \brief Write a buffer of PEM information from a DER encoded 138 * buffer. 139 * 140 * \param header The header string to write. 141 * \param footer The footer string to write. 142 * \param der_data The DER data to encode. 143 * \param der_len The length of the DER data \p der_data in Bytes. 144 * \param buf The buffer to write to. 145 * \param buf_len The length of the output buffer \p buf in Bytes. 146 * \param olen The address at which to store the total length written 147 * or required (if \p buf_len is not enough). 148 * 149 * \note You may pass \c NULL for \p buf and \c 0 for \p buf_len 150 * to request the length of the resulting PEM buffer in 151 * `*olen`. 152 * 153 * \note This function may be called with overlapping \p der_data 154 * and \p buf buffers. 155 * 156 * \return \c 0 on success. 157 * \return #MBEDTLS_ERR_BASE64_BUFFER_TOO_SMALL if \p buf isn't large 158 * enough to hold the PEM buffer. In this case, `*olen` holds 159 * the required minimum size of \p buf. 160 * \return Another PEM or BASE64 error code on other kinds of failure. 161 */ 162 int mbedtls_pem_write_buffer( const char *header, const char *footer, 163 const unsigned char *der_data, size_t der_len, 164 unsigned char *buf, size_t buf_len, size_t *olen ); 165 #endif /* MBEDTLS_PEM_WRITE_C */ 166 167 #ifdef __cplusplus 168 } 169 #endif 170 171 #endif /* pem.h */ 172