ceph/src/spdk/include/spdk/base64.h

   1 /*-
   2  *   BSD LICENSE
   3  *
   4  *   Copyright (c) Intel Corporation.
   5  *   All rights reserved.
   6  *
   7  *   Redistribution and use in source and binary forms, with or without
   8  *   modification, are permitted provided that the following conditions
   9  *   are met:
  10  *
  11  *     * Redistributions of source code must retain the above copyright
  12  *       notice, this list of conditions and the following disclaimer.
  13  *     * Redistributions in binary form must reproduce the above copyright
  14  *       notice, this list of conditions and the following disclaimer in
  15  *       the documentation and/or other materials provided with the
  16  *       distribution.
  17  *     * Neither the name of Intel Corporation nor the names of its
  18  *       contributors may be used to endorse or promote products derived
  19  *       from this software without specific prior written permission.
  20  *
  21  *   THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
  22  *   "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
  23  *   LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
  24  *   A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
  25  *   OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
  26  *   SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
  27  *   LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
  28  *   DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
  29  *   THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
  30  *   (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
  31  *   OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
  32  */
  33
  34 /**
  35  * \file
  36  * Base64 utility functions
  37  */
  38
  39 #ifndef SPDK_BASE64_H
  40 #define SPDK_BASE64_H
  41
  42 #include "spdk/stdinc.h"
  43
  44 #ifdef __cplusplus
  45 extern "C" {
  46 #endif
  47
  48 /**
  49  * Following the Base64 part in RFC4648:
  50  * https://tools.ietf.org/html/rfc4648.html
  51  */
  52
  53 /**
  54  * Calculate strlen of encoded Base64 string based on raw buffer length.
  55  *
  56  * \param raw_len Length of raw buffer.
  57  * \return Encoded Base64 string length, excluding the terminating null byte ('\0').
  58  */
  59 static inline size_t spdk_base64_get_encoded_strlen(size_t raw_len)
  60 {
  61         return (raw_len + 2) / 3 * 4;
  62 }
  63
  64 /**
  65  * Calculate length of raw buffer based on strlen of encoded Base64.
  66  *
  67  * \param encoded_strlen Length of enocded Base64 string, excluding terminating null byte ('\0').
  68  * \return Length of raw buffer.
  69  */
  70 static inline size_t spdk_base64_get_decoded_len(size_t encoded_strlen)
  71 {
  72         /* text_strlen and raw_len should be (4n,3n), (4n+2, 3n+1) or (4n+3, 3n+2) */
  73         return encoded_strlen / 4 * 3 + ((encoded_strlen % 4 + 1) / 2);
  74 }
  75
  76 /**
  77  * Base 64 Encoding with Standard Base64 Alphabet defined in RFC4684.
  78  *
  79  * \param dst Buffer address of encoded Base64 string. Its length should be enough
  80  * to contain Base64 string and the terminating null byte ('\0'), so it needs to be at
  81  * least as long as 1 + spdk_base64_get_encoded_strlen(src_len).
  82  * \param src Raw data buffer to be encoded.
  83  * \param src_len Length of raw data buffer.
  84  *
  85  * \return 0 on success.
  86  * \return -EINVAL if dst or src is NULL, or binary_len <= 0.
  87  */
  88 int spdk_base64_encode(char *dst, const void *src, size_t src_len);
  89
  90 /**
  91  * Base 64 Encoding with URL and Filename Safe Alphabet.
  92  *
  93  * \param dst Buffer address of encoded Base64 string. Its length should be enough
  94  * to contain Base64 string and the terminating null byte ('\0'), so it needs to be at
  95  * least as long as 1 + spdk_base64_get_encoded_strlen(src_len).
  96  * \param src Raw data buffer to be encoded.
  97  * \param src_len Length of raw data buffer.
  98  *
  99  * \return 0 on success.
 100  * \return -EINVAL if dst or src is NULL, or binary_len <= 0.
 101  */
 102 int spdk_base64_urlsafe_encode(char *dst, const void *src, size_t src_len);
 103
 104 /**
 105  * Base 64 Decoding with Standard Base64 Alphabet defined in RFC4684.
 106  *
 107  * \param dst Buffer address of decoded raw data. Its length should be enough
 108  * to contain decoded raw data, so it needs to be at least as long as
 109  * spdk_base64_get_decoded_len(encoded_strlen).
 110  * \param dst_len Output parameter for the length of actual decoded raw data.
 111  * If NULL, the actual decoded length won't be returned.
 112  * \param src Data buffer for base64 string to be decoded.
 113  *
 114  * \return 0 on success.
 115  * \return -EINVAL if dst or src is NULL, or content of src is illegal.
 116  */
 117 int spdk_base64_decode(void *dst, size_t *dst_len, const char *src);
 118
 119 /**
 120  * Base 64 Decoding with URL and Filename Safe Alphabet.
 121  *
 122  * \param dst Buffer address of decoded raw data. Its length should be enough
 123  * to contain decoded raw data, so it needs to be at least as long as
 124  * spdk_base64_get_decoded_len(encoded_strlen).
 125  * \param dst_len Output parameter for the length of actual decoded raw data.
 126  * If NULL, the actual decoded length won't be returned.
 127  * \param src Data buffer for base64 string to be decoded.
 128  *
 129  * \return 0 on success.
 130  * \return -EINVAL if dst or src is NULL, or content of src is illegal.
 131  */
 132 int spdk_base64_urlsafe_decode(void *dst, size_t *dst_len, const char *src);
 133
 134 #ifdef __cplusplus
 135 }
 136 #endif
 137
 138 #endif /* SPDK_BASE64_H */