1 /* $NetBSD: store_mem.c,v 1.1.1.2 2014/04/24 12:45:51 pettai Exp $ */ 2 3 /* 4 * Copyright (c) 1997 - 2000, 2002 Kungliga Tekniska Högskolan 5 * (Royal Institute of Technology, Stockholm, Sweden). 6 * All rights reserved. 7 * 8 * Redistribution and use in source and binary forms, with or without 9 * modification, are permitted provided that the following conditions 10 * are met: 11 * 12 * 1. Redistributions of source code must retain the above copyright 13 * notice, this list of conditions and the following disclaimer. 14 * 15 * 2. Redistributions in binary form must reproduce the above copyright 16 * notice, this list of conditions and the following disclaimer in the 17 * documentation and/or other materials provided with the distribution. 18 * 19 * 3. Neither the name of the Institute nor the names of its contributors 20 * may be used to endorse or promote products derived from this software 21 * without specific prior written permission. 22 * 23 * THIS SOFTWARE IS PROVIDED BY THE INSTITUTE AND CONTRIBUTORS ``AS IS'' AND 24 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 25 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 26 * ARE DISCLAIMED. IN NO EVENT SHALL THE INSTITUTE OR CONTRIBUTORS BE LIABLE 27 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 28 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 29 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 30 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 31 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 32 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 33 * SUCH DAMAGE. 34 */ 35 36 #include "krb5_locl.h" 37 #include "store-int.h" 38 39 typedef struct mem_storage{ 40 unsigned char *base; 41 size_t size; 42 unsigned char *ptr; 43 }mem_storage; 44 45 static ssize_t 46 mem_fetch(krb5_storage *sp, void *data, size_t size) 47 { 48 mem_storage *s = (mem_storage*)sp->data; 49 if(size > (size_t)(s->base + s->size - s->ptr)) 50 size = s->base + s->size - s->ptr; 51 memmove(data, s->ptr, size); 52 sp->seek(sp, size, SEEK_CUR); 53 return size; 54 } 55 56 static ssize_t 57 mem_store(krb5_storage *sp, const void *data, size_t size) 58 { 59 mem_storage *s = (mem_storage*)sp->data; 60 if(size > (size_t)(s->base + s->size - s->ptr)) 61 size = s->base + s->size - s->ptr; 62 memmove(s->ptr, data, size); 63 sp->seek(sp, size, SEEK_CUR); 64 return size; 65 } 66 67 static ssize_t 68 mem_no_store(krb5_storage *sp, const void *data, size_t size) 69 { 70 return -1; 71 } 72 73 static off_t 74 mem_seek(krb5_storage *sp, off_t offset, int whence) 75 { 76 mem_storage *s = (mem_storage*)sp->data; 77 switch(whence){ 78 case SEEK_SET: 79 if((size_t)offset > s->size) 80 offset = s->size; 81 if(offset < 0) 82 offset = 0; 83 s->ptr = s->base + offset; 84 break; 85 case SEEK_CUR: 86 return sp->seek(sp, s->ptr - s->base + offset, SEEK_SET); 87 case SEEK_END: 88 return sp->seek(sp, s->size + offset, SEEK_SET); 89 default: 90 errno = EINVAL; 91 return -1; 92 } 93 return s->ptr - s->base; 94 } 95 96 static int 97 mem_trunc(krb5_storage *sp, off_t offset) 98 { 99 mem_storage *s = (mem_storage*)sp->data; 100 if((size_t)offset > s->size) 101 return ERANGE; 102 s->size = offset; 103 if ((s->ptr - s->base) > offset) 104 s->ptr = s->base + offset; 105 return 0; 106 } 107 108 static int 109 mem_no_trunc(krb5_storage *sp, off_t offset) 110 { 111 return EINVAL; 112 } 113 114 /** 115 * Create a fixed size memory storage block 116 * 117 * @return A krb5_storage on success, or NULL on out of memory error. 118 * 119 * @ingroup krb5_storage 120 * 121 * @sa krb5_storage_mem() 122 * @sa krb5_storage_from_readonly_mem() 123 * @sa krb5_storage_from_data() 124 * @sa krb5_storage_from_fd() 125 */ 126 127 KRB5_LIB_FUNCTION krb5_storage * KRB5_LIB_CALL 128 krb5_storage_from_mem(void *buf, size_t len) 129 { 130 krb5_storage *sp = malloc(sizeof(krb5_storage)); 131 mem_storage *s; 132 if(sp == NULL) 133 return NULL; 134 s = malloc(sizeof(*s)); 135 if(s == NULL) { 136 free(sp); 137 return NULL; 138 } 139 sp->data = s; 140 sp->flags = 0; 141 sp->eof_code = HEIM_ERR_EOF; 142 s->base = buf; 143 s->size = len; 144 s->ptr = buf; 145 sp->fetch = mem_fetch; 146 sp->store = mem_store; 147 sp->seek = mem_seek; 148 sp->trunc = mem_trunc; 149 sp->free = NULL; 150 sp->max_alloc = UINT_MAX/8; 151 return sp; 152 } 153 154 /** 155 * Create a fixed size memory storage block 156 * 157 * @return A krb5_storage on success, or NULL on out of memory error. 158 * 159 * @ingroup krb5_storage 160 * 161 * @sa krb5_storage_mem() 162 * @sa krb5_storage_from_mem() 163 * @sa krb5_storage_from_readonly_mem() 164 * @sa krb5_storage_from_fd() 165 */ 166 167 KRB5_LIB_FUNCTION krb5_storage * KRB5_LIB_CALL 168 krb5_storage_from_data(krb5_data *data) 169 { 170 return krb5_storage_from_mem(data->data, data->length); 171 } 172 173 /** 174 * Create a fixed size memory storage block that is read only 175 * 176 * @return A krb5_storage on success, or NULL on out of memory error. 177 * 178 * @ingroup krb5_storage 179 * 180 * @sa krb5_storage_mem() 181 * @sa krb5_storage_from_mem() 182 * @sa krb5_storage_from_data() 183 * @sa krb5_storage_from_fd() 184 */ 185 186 KRB5_LIB_FUNCTION krb5_storage * KRB5_LIB_CALL 187 krb5_storage_from_readonly_mem(const void *buf, size_t len) 188 { 189 krb5_storage *sp = malloc(sizeof(krb5_storage)); 190 mem_storage *s; 191 if(sp == NULL) 192 return NULL; 193 s = malloc(sizeof(*s)); 194 if(s == NULL) { 195 free(sp); 196 return NULL; 197 } 198 sp->data = s; 199 sp->flags = 0; 200 sp->eof_code = HEIM_ERR_EOF; 201 s->base = rk_UNCONST(buf); 202 s->size = len; 203 s->ptr = rk_UNCONST(buf); 204 sp->fetch = mem_fetch; 205 sp->store = mem_no_store; 206 sp->seek = mem_seek; 207 sp->trunc = mem_no_trunc; 208 sp->free = NULL; 209 sp->max_alloc = UINT_MAX/8; 210 return sp; 211 } 212