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,v 1.11 2002/04/18 14:00:44 joda Exp $"); 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 off_t 68 mem_seek(krb5_storage *sp, off_t offset, int whence) 69 { 70 mem_storage *s = (mem_storage*)sp->data; 71 switch(whence){ 72 case SEEK_SET: 73 if(offset > s->size) 74 offset = s->size; 75 if(offset < 0) 76 offset = 0; 77 s->ptr = s->base + offset; 78 break; 79 case SEEK_CUR: 80 return sp->seek(sp, s->ptr - s->base + offset, SEEK_SET); 81 case SEEK_END: 82 return sp->seek(sp, s->size + offset, SEEK_SET); 83 default: 84 errno = EINVAL; 85 return -1; 86 } 87 return s->ptr - s->base; 88 } 89 90 krb5_storage * 91 krb5_storage_from_mem(void *buf, size_t len) 92 { 93 krb5_storage *sp = malloc(sizeof(krb5_storage)); 94 mem_storage *s; 95 if(sp == NULL) 96 return NULL; 97 s = malloc(sizeof(*s)); 98 if(s == NULL) { 99 free(sp); 100 return NULL; 101 } 102 sp->data = s; 103 sp->flags = 0; 104 sp->eof_code = HEIM_ERR_EOF; 105 s->base = buf; 106 s->size = len; 107 s->ptr = buf; 108 sp->fetch = mem_fetch; 109 sp->store = mem_store; 110 sp->seek = mem_seek; 111 sp->free = NULL; 112 return sp; 113 } 114 115 krb5_storage * 116 krb5_storage_from_data(krb5_data *data) 117 { 118 return krb5_storage_from_mem(data->data, data->length); 119 } 120