1 /* 2 * Copyright (c) 1997 - 2000, 2002 Kungliga Tekniska H�gskolan 3 * (Royal Institute of Technology, Stockholm, Sweden). 4 * All rights reserved. 5 * 6 * Redistribution and use in source and binary forms, with or without 7 * modification, are permitted provided that the following conditions 8 * are met: 9 * 10 * 1. Redistributions of source code must retain the above copyright 11 * notice, this list of conditions and the following disclaimer. 12 * 13 * 2. Redistributions in binary form must reproduce the above copyright 14 * notice, this list of conditions and the following disclaimer in the 15 * documentation and/or other materials provided with the distribution. 16 * 17 * 3. Neither the name of the Institute nor the names of its contributors 18 * may be used to endorse or promote products derived from this software 19 * without specific prior written permission. 20 * 21 * THIS SOFTWARE IS PROVIDED BY THE INSTITUTE AND CONTRIBUTORS ``AS IS'' AND 22 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 23 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 24 * ARE DISCLAIMED. IN NO EVENT SHALL THE INSTITUTE OR CONTRIBUTORS BE LIABLE 25 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 26 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 27 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 28 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 29 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 30 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 31 * SUCH DAMAGE. 32 */ 33 34 #include "krb5_locl.h" 35 #include "store-int.h" 36 37 RCSID("$Id: store_mem.c 20307 2007-04-11 11:16:28Z lha $"); 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 > 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 > 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(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 krb5_storage * KRB5_LIB_FUNCTION 97 krb5_storage_from_mem(void *buf, size_t len) 98 { 99 krb5_storage *sp = malloc(sizeof(krb5_storage)); 100 mem_storage *s; 101 if(sp == NULL) 102 return NULL; 103 s = malloc(sizeof(*s)); 104 if(s == NULL) { 105 free(sp); 106 return NULL; 107 } 108 sp->data = s; 109 sp->flags = 0; 110 sp->eof_code = HEIM_ERR_EOF; 111 s->base = buf; 112 s->size = len; 113 s->ptr = buf; 114 sp->fetch = mem_fetch; 115 sp->store = mem_store; 116 sp->seek = mem_seek; 117 sp->free = NULL; 118 return sp; 119 } 120 121 krb5_storage * KRB5_LIB_FUNCTION 122 krb5_storage_from_data(krb5_data *data) 123 { 124 return krb5_storage_from_mem(data->data, data->length); 125 } 126 127 krb5_storage * KRB5_LIB_FUNCTION 128 krb5_storage_from_readonly_mem(const 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 = rk_UNCONST(buf); 143 s->size = len; 144 s->ptr = rk_UNCONST(buf); 145 sp->fetch = mem_fetch; 146 sp->store = mem_no_store; 147 sp->seek = mem_seek; 148 sp->free = NULL; 149 return sp; 150 } 151