1/** 2 * @copyright 3 * ==================================================================== 4 * Licensed to the Apache Software Foundation (ASF) under one 5 * or more contributor license agreements. See the NOTICE file 6 * distributed with this work for additional information 7 * regarding copyright ownership. The ASF licenses this file 8 * to you under the Apache License, Version 2.0 (the 9 * "License"); you may not use this file except in compliance 10 * with the License. You may obtain a copy of the License at 11 * 12 * http://www.apache.org/licenses/LICENSE-2.0 13 * 14 * Unless required by applicable law or agreed to in writing, 15 * software distributed under the License is distributed on an 16 * "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY 17 * KIND, either express or implied. See the License for the 18 * specific language governing permissions and limitations 19 * under the License. 20 * ==================================================================== 21 * @endcopyright 22 * 23 * @file svn_checksum.h 24 * @brief Subversion checksum routines 25 */ 26 27#ifndef SVN_CHECKSUM_H 28#define SVN_CHECKSUM_H 29 30#include <apr.h> /* for apr_size_t */ 31#include <apr_pools.h> /* for apr_pool_t */ 32 33#include "svn_types.h" /* for svn_boolean_t, svn_error_t */ 34 35#ifdef __cplusplus 36extern "C" { 37#endif /* __cplusplus */ 38 39 40/** 41 * Various types of checksums. 42 * 43 * @since New in 1.6. 44 */ 45typedef enum svn_checksum_kind_t 46{ 47 /** The checksum is (or should be set to) an MD5 checksum. */ 48 svn_checksum_md5, 49 50 /** The checksum is (or should be set to) a SHA1 checksum. */ 51 svn_checksum_sha1, 52 53 /** The checksum is (or should be set to) a FNV-1a 32 bit checksum, 54 * in big endian byte order. 55 * @since New in 1.9. */ 56 svn_checksum_fnv1a_32, 57 58 /** The checksum is (or should be set to) a modified FNV-1a 32 bit, 59 * in big endian byte order. 60 * @since New in 1.9. */ 61 svn_checksum_fnv1a_32x4 62} svn_checksum_kind_t; 63 64/** 65 * A generic checksum representation. 66 * 67 * @since New in 1.6. 68 */ 69typedef struct svn_checksum_t 70{ 71 /** The bytes of the checksum. */ 72 const unsigned char *digest; 73 74 /** The type of the checksum. This should never be changed by consumers 75 of the APIs. */ 76 svn_checksum_kind_t kind; 77} svn_checksum_t; 78 79/** 80 * Opaque type for creating checksums of data. 81 */ 82typedef struct svn_checksum_ctx_t svn_checksum_ctx_t; 83 84/** Return a new checksum structure of type @a kind, initialized to the all- 85 * zeros value, allocated in @a pool. 86 * 87 * @since New in 1.6. 88 */ 89svn_checksum_t * 90svn_checksum_create(svn_checksum_kind_t kind, 91 apr_pool_t *pool); 92 93/** Set @a checksum->digest to all zeros, which, by convention, matches 94 * all other checksums. 95 * 96 * @since New in 1.6. 97 */ 98svn_error_t * 99svn_checksum_clear(svn_checksum_t *checksum); 100 101/** Compare checksums @a checksum1 and @a checksum2. If their kinds do not 102 * match or if neither is all zeros, and their content does not match, then 103 * return FALSE; else return TRUE. 104 * 105 * @since New in 1.6. 106 */ 107svn_boolean_t 108svn_checksum_match(const svn_checksum_t *checksum1, 109 const svn_checksum_t *checksum2); 110 111 112/** 113 * Return a deep copy of @a checksum, allocated in @a pool. If @a 114 * checksum is NULL then NULL is returned. 115 * 116 * @since New in 1.6. 117 */ 118svn_checksum_t * 119svn_checksum_dup(const svn_checksum_t *checksum, 120 apr_pool_t *pool); 121 122 123/** Return the hex representation of @a checksum, allocating the string 124 * in @a pool. 125 * 126 * @since New in 1.6. 127 */ 128const char * 129svn_checksum_to_cstring_display(const svn_checksum_t *checksum, 130 apr_pool_t *pool); 131 132 133/** Return the hex representation of @a checksum, allocating the 134 * string in @a pool. If @a checksum->digest is all zeros (that is, 135 * 0, not '0') then return NULL. In 1.7+, @a checksum may be NULL 136 * and NULL will be returned in that case. 137 * 138 * @since New in 1.6. 139 * @note Passing NULL for @a checksum in 1.6 will cause a segfault. 140 */ 141const char * 142svn_checksum_to_cstring(const svn_checksum_t *checksum, 143 apr_pool_t *pool); 144 145 146/** Return a serialized representation of @a checksum, allocated in 147 * @a result_pool. Temporary allocations are performed in @a scratch_pool. 148 * 149 * Note that @a checksum may not be NULL. 150 * 151 * @since New in 1.7. 152 */ 153const char * 154svn_checksum_serialize(const svn_checksum_t *checksum, 155 apr_pool_t *result_pool, 156 apr_pool_t *scratch_pool); 157 158 159/** Return @a checksum from the serialized format at @a data. The checksum 160 * will be allocated in @a result_pool, with any temporary allocations 161 * performed in @a scratch_pool. 162 * 163 * @since New in 1.7. 164 */ 165svn_error_t * 166svn_checksum_deserialize(const svn_checksum_t **checksum, 167 const char *data, 168 apr_pool_t *result_pool, 169 apr_pool_t *scratch_pool); 170 171 172/** Parse the hex representation @a hex of a checksum of kind @a kind and 173 * set @a *checksum to the result, allocating in @a pool. 174 * 175 * If @a hex is @c NULL or is the all-zeros checksum, then set @a *checksum 176 * to @c NULL. 177 * 178 * @since New in 1.6. 179 */ 180/* ### TODO: When revving this, make it set @a *checksum to a non-NULL struct 181 * ### when @a hex is the all-zeroes checksum. See 182 * ### http://mail-archives.apache.org/mod_mbox/subversion-dev/201609.mbox/%3c00cd26ab-bdb3-67b4-ca6b-063266493874%40apache.org%3e 183 */ 184svn_error_t * 185svn_checksum_parse_hex(svn_checksum_t **checksum, 186 svn_checksum_kind_t kind, 187 const char *hex, 188 apr_pool_t *pool); 189 190/** 191 * Return in @a *checksum the checksum of type @a kind for the bytes beginning 192 * at @a data, and going for @a len. @a *checksum is allocated in @a pool. 193 * 194 * @since New in 1.6. 195 */ 196svn_error_t * 197svn_checksum(svn_checksum_t **checksum, 198 svn_checksum_kind_t kind, 199 const void *data, 200 apr_size_t len, 201 apr_pool_t *pool); 202 203 204/** 205 * Return in @a pool a newly allocated checksum populated with the checksum 206 * of type @a kind for the empty string. 207 * 208 * @since New in 1.6. 209 */ 210svn_checksum_t * 211svn_checksum_empty_checksum(svn_checksum_kind_t kind, 212 apr_pool_t *pool); 213 214 215/** 216 * Create a new @c svn_checksum_ctx_t structure, allocated from @a pool for 217 * calculating checksums of type @a kind. @see svn_checksum_final() 218 * 219 * @since New in 1.6. 220 */ 221svn_checksum_ctx_t * 222svn_checksum_ctx_create(svn_checksum_kind_t kind, 223 apr_pool_t *pool); 224 225/** 226 * Reset an existing checksum @a ctx to initial state. 227 * @see svn_checksum_ctx_create() 228 * 229 * @since New in 1.10. 230 */ 231svn_error_t * 232svn_checksum_ctx_reset(svn_checksum_ctx_t *ctx); 233 234/** 235 * Update the checksum represented by @a ctx, with @a len bytes starting at 236 * @a data. 237 * 238 * @since New in 1.6. 239 */ 240svn_error_t * 241svn_checksum_update(svn_checksum_ctx_t *ctx, 242 const void *data, 243 apr_size_t len); 244 245 246/** 247 * Finalize the checksum used when creating @a ctx, and put the resultant 248 * checksum in @a *checksum, allocated in @a pool. 249 * 250 * @since New in 1.6. 251 */ 252svn_error_t * 253svn_checksum_final(svn_checksum_t **checksum, 254 const svn_checksum_ctx_t *ctx, 255 apr_pool_t *pool); 256 257 258/** 259 * Return the digest size of @a checksum. 260 * 261 * @since New in 1.6. 262 */ 263apr_size_t 264svn_checksum_size(const svn_checksum_t *checksum); 265 266/** 267 * Return @c TRUE iff @a checksum matches the checksum for the empty 268 * string. 269 * 270 * @since New in 1.8. 271 */ 272svn_boolean_t 273svn_checksum_is_empty_checksum(svn_checksum_t *checksum); 274 275 276/** 277 * Return an error of type #SVN_ERR_CHECKSUM_MISMATCH for @a actual and 278 * @a expected checksums which do not match. Use @a fmt, and the following 279 * parameters to populate the error message. 280 * 281 * @note This function does not actually check for the mismatch, it just 282 * constructs the error. 283 * 284 * @a scratch_pool is used for temporary allocations; the returned error 285 * will be allocated in its own pool (as is typical). 286 * 287 * @since New in 1.7. 288 */ 289svn_error_t * 290svn_checksum_mismatch_err(const svn_checksum_t *expected, 291 const svn_checksum_t *actual, 292 apr_pool_t *scratch_pool, 293 const char *fmt, 294 ...) 295 __attribute__ ((format(printf, 4, 5))); 296 297#ifdef __cplusplus 298} 299#endif /* __cplusplus */ 300 301#endif /* SVN_CHECKSUM_H */ 302