1/* /////////////////////////////////////////////////////////////////////////////
2 * File:        b64/b64.h
3 *
4 * Purpose:     Header file for the b64 library
5 *
6 * Created:     18th October 2004
7 * Updated:     2nd August 2006
8 *
9 * Thanks:      To Adam McLaurin, for ideas regarding the SecBase64Decode2() and SecBase64Encode2().
10 *
11 * Home:        http://synesis.com.au/software/
12 *
13 * Copyright (c) 2004-2006, Matthew Wilson and Synesis Software
14 * All rights reserved.
15 *
16 * Redistribution and use in source and binary forms, with or without
17 * modification, are permitted provided that the following conditions are met:
18 *
19 * - Redistributions of source code must retain the above copyright notice, this
20 *   list of conditions and the following disclaimer.
21 * - Redistributions in binary form must reproduce the above copyright notice,
22 *   this list of conditions and the following disclaimer in the documentation
23 *   and/or other materials provided with the distribution.
24 * - Neither the name(s) of Matthew Wilson and Synesis Software nor the names of
25 *   any contributors may be used to endorse or promote products derived from
26 *   this software without specific prior written permission.
27 *
28 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
29 * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
30 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
31 * ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE
32 * LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
33 * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
34 * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
35 * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
36 * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
37 * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
38 * POSSIBILITY OF SUCH DAMAGE.
39 *
40 * ////////////////////////////////////////////////////////////////////////// */
41
42
43/** \file b64/b64.h
44 *
45 * \brief [C/C++] Header file for the b64 library.
46 */
47
48#ifndef _SEC_BASE64_H_
49#define _SEC_BASE64_H_
50
51#include <stdint.h>
52#include <stddef.h>
53
54#ifdef __cplusplus
55extern "C" {
56#endif /* __cplusplus */
57
58/* /////////////////////////////////////////////////////////////////////////////
59 * Enumerations
60 */
61
62/** \brief Return codes (from SecBase64Encode2() / SecBase64Decode2())
63 */
64enum
65{
66    kSecB64_R_OK                   =   0,   /*!< operation was successful. */
67    kSecB64_R_INSUFFICIENT_BUFFER  =   1,   /*!< The given translation buffer was not of sufficient size. */
68    kSecB64_R_TRUNCATED_INPUT      =   2,   /*!< The input did not represent a fully formed stream of octet couplings. */
69    kSecB64_R_DATA_ERROR           =   3   /*!< invalid data. */
70};
71
72typedef uint32_t SecBase64Result;
73
74/** \brief Coding behaviour modification flags (for SecBase64Encode2() / SecBase64Decode2())
75 */
76enum
77{
78        kSecB64_F_LINE_LEN_USE_PARAM    =   0x0000  /*!< Uses the lineLen parameter to SecBase64Encode2(). Ignored by SecBase64Decode2(). */
79    ,   kSecB64_F_LINE_LEN_INFINITE     =   0x0001  /*!< Ignores the lineLen parameter to SecBase64Encode2(). Line length is infinite. Ignored by SecBase64Decode2(). */
80    ,   kSecB64_F_LINE_LEN_64           =   0x0002  /*!< Ignores the lineLen parameter to SecBase64Encode2(). Line length is 64. Ignored by SecBase64Decode2(). */
81    ,   kSecB64_F_LINE_LEN_76           =   0x0003  /*!< Ignores the lineLen parameter to SecBase64Encode2(). Line length is 76. Ignored by SecBase64Decode2(). */
82    ,   kSecB64_F_LINE_LEN_MASK         =   0x000f  /*!< Mask for testing line length flags to SecBase64Encode2(). Ignored by SecBase64Encode2(). */
83    ,   kSecB64_F_STOP_ON_NOTHING       =   0x0000  /*!< Decoding ignores all invalid characters in the input data. Ignored by SecBase64Encode2(). */
84    ,   kSecB64_F_STOP_ON_UNKNOWN_CHAR  =   0x0100  /*!< Causes decoding to break if any non-Base-64 [a-zA-Z0-9=+/], non-whitespace character is encountered. Ignored by SecBase64Encode2(). */
85    ,   kSecB64_F_STOP_ON_UNEXPECTED_WS =   0x0200  /*!< Causes decoding to break if any unexpected whitespace is encountered. Ignored by SecBase64Encode2(). */
86    ,   kSecB64_F_STOP_ON_BAD_CHAR      =   0x0300  /*!< Causes decoding to break if any non-Base-64 [a-zA-Z0-9=+/] character is encountered. Ignored by SecBase64Encode2(). */
87};
88
89typedef uint32_t SecBase64Flags;
90
91/* /////////////////////////////////////////////////////////////////////////////
92 * Functions
93 */
94
95#if 0
96static inline size_t SecBase64EncodedSize(size_t srcSize, size_t lineLen) {
97    size_t total = (((srcSize) + 2) / 3) * 4;
98    size_t lineLen = (lineLen);
99    if (lineLen > 0) {
100        size_t numLines = (total + (lineLen - 1)) / lineLen;
101        total += 2 * (numLines - 1);
102    }
103    return total;
104}
105#endif
106
107/** \brief Encodes a block of binary data into base64
108 *
109 * \param src Pointer to the block to be encoded. May not be NULL, except when
110 *   \c dest is NULL, in which case it is ignored.
111 * \param srcSize Length of block to be encoded
112 * \param dest Pointer to the buffer into which the result is to be written. May
113 *   be NULL, in which case the function returns the required length
114 * \param destLen Length of the buffer into which the result is to be written. Must
115 *   be at least as large as that indicated by the return value from
116 * \c SecBase64Encode()(NULL, srcSize, NULL, 0).
117 *
118 * \return 0 if the size of the buffer was insufficient, or the length of the
119 * converted buffer was longer than \c destLen
120 *
121 * \note The function returns the required length if \c dest is NULL
122 *
123 * \note The function returns the required length if \c dest is NULL. The returned size
124 *   might be larger than the actual required size, but will never be smaller.
125 *
126 * \note Threading: The function is fully re-entrant.
127 */
128size_t SecBase64Encode(void const *src, size_t srcSize, char *dest, size_t destLen);
129
130/** \brief Encodes a block of binary data into base64
131 *
132 * \param src Pointer to the block to be encoded. May not be NULL, except when
133 *   \c dest is NULL, in which case it is ignored.
134 * \param srcSize Length of block to be encoded
135 * \param dest Pointer to the buffer into which the result is to be written. May
136 *   be NULL, in which case the function returns the required length
137 * \param destLen Length of the buffer into which the result is to be written. Must
138 *   be at least as large as that indicated by the return value from
139 *   \c SecBase64Encode()(NULL, srcSize, NULL, 0).
140 * \param flags A combination of the SecBase64Flags enumeration, that moderate the
141 *   behaviour of the function
142 * \param lineLen If the flags parameter contains kSecB64_F_LINE_LEN_USE_PARAM, then
143 *   this parameter represents the length of the lines into which the encoded form is split,
144 *   with a hard line break ('\\r\\n'). If this value is 0, then the line is not
145 *   split. If it is <0, then the RFC-1113 recommended line length of 64 is used
146 * \param rc The return code representing the status of the operation. May be NULL.
147 *
148 * \return 0 if the size of the buffer was insufficient, or the length of the
149 *   converted buffer was longer than \c destLen
150 *
151 * \note The function returns the required length if \c dest is NULL. The returned size
152 *   might be larger than the actual required size, but will never be smaller.
153 *
154 * \note Threading: The function is fully re-entrant.
155 */
156size_t SecBase64Encode2( void const  *src
157                ,   size_t      srcSize
158                ,   char        *dest
159                ,   size_t      destLen
160                ,   unsigned    flags
161                ,   int         lineLen /* = 0 */
162                ,   SecBase64Result      *rc     /* = NULL */);
163
164/** \brief Decodes a sequence of base64 into a block of binary data
165 *
166 * \param src Pointer to the base64 block to be decoded. May not be NULL, except when
167 *   \c dest is NULL, in which case it is ignored. If \c dest is NULL, and \c src is
168 *   <b>not</b> NULL, then the returned value is calculated exactly, otherwise a value
169 *   is returned that is guaranteed to be large enough to hold the decoded block.
170 *
171 * \param srcLen Length of block to be encoded. Must be an integral of 4, the base64
172 *   encoding quantum, otherwise the base64 block is assumed to be invalid
173 * \param dest Pointer to the buffer into which the result is to be written. May
174 *   be NULL, in which case the function returns the required length
175 * \param destSize Length of the buffer into which the result is to be written. Must
176 *   be at least as large as that indicated by the return value from
177 *   \c SecBase64Decode(src, srcSize, NULL, 0), even in the case where the encoded form
178 *   contains a number of characters that will be ignored, resulting in a lower total
179 *   length of converted form.
180 *
181 * \return 0 if the size of the buffer was insufficient, or the length of the
182 *   converted buffer was longer than \c destSize
183 *
184 * \note The function returns the required length if \c dest is NULL. The returned size
185 *   might be larger than the actual required size, but will never be smaller.
186 *
187 * \note \anchor anchor__4_characters The behaviour of both
188 * \link b64::SecBase64Encode2 SecBase64Encode2()\endlink
189 * and
190 * \link b64::SecBase64Decode2 SecBase64Decode2()\endlink
191 * are undefined if the line length is not a multiple of 4.
192 *
193 * \note Threading: The function is fully re-entrant.
194 */
195size_t SecBase64Decode(char const *src, size_t srcLen, void *dest, size_t destSize);
196
197/** \brief Decodes a sequence of base64 into a block of binary data
198 *
199 * \param src Pointer to the base64 block to be decoded. May not be NULL, except when
200 * \c dest is NULL, in which case it is ignored. If \c dest is NULL, and \c src is
201 * <b>not</b> NULL, then the returned value is calculated exactly, otherwise a value
202 * is returned that is guaranteed to be large enough to hold the decoded block.
203 *
204 * \param srcLen Length of block to be encoded. Must be an integral of 4, the base64
205 *   encoding quantum, otherwise the base64 block is assumed to be invalid
206 * \param dest Pointer to the buffer into which the result is to be written. May
207 *   be NULL, in which case the function returns the required length
208 * \param destSize Length of the buffer into which the result is to be written. Must
209 *   be at least as large as that indicated by the return value from
210 *   \c SecBase64Decode(src, srcSize, NULL, 0), even in the case where the encoded form
211 *   contains a number of characters that will be ignored, resulting in a lower total
212 *   length of converted form.
213 * \param flags A combination of the SecBase64Flags enumeration, that moderate the
214 *   behaviour of the function.
215 * \param rc The return code representing the status of the operation. May be NULL.
216 * \param badChar If the flags parameter does not contain kSecB64_F_STOP_ON_NOTHING, this
217 *   parameter specifies the address of a pointer that will be set to point to any
218 *   character in the sequence that stops the parsing, as dictated by the flags
219 *   parameter. May be NULL.
220 *
221 * \return 0 if the size of the buffer was insufficient, or the length of the
222 * converted buffer was longer than \c destSize, or a bad character stopped parsing.
223 *
224 * \note The function returns the required length if \c dest is NULL. The returned size
225 *   might be larger than the actual required size, but will never be smaller.
226 *
227 * \note The behaviour of both
228 * \link b64::SecBase64Encode2 SecBase64Encode2()\endlink
229 * and
230 * \link b64::SecBase64Decode2 SecBase64Decode2()\endlink
231 * are undefined if the line length is not a multiple of 4.
232 *
233 * \note Threading: The function is fully re-entrant.
234 */
235size_t SecBase64Decode2( char const  *src
236                ,   size_t      srcLen
237                ,   void        *dest
238                ,   size_t      destSize
239                ,   unsigned    flags
240                ,   char const  **badChar   /* = NULL */
241                ,   SecBase64Result      *rc         /* = NULL */);
242
243#ifdef __cplusplus
244}
245#endif /* __cplusplus */
246
247#endif /* _SEC_BASE64_H_ */
248