freebsd-dev/crypto/heimdal/lib/krb5/store_mem.c

120 lines
3.5 KiB
C

/*
* Copyright (c) 1997 - 2000, 2002 Kungliga Tekniska Högskolan
* (Royal Institute of Technology, Stockholm, Sweden).
* All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
*
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
*
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
*
* 3. Neither the name of the Institute nor the names of its contributors
* may be used to endorse or promote products derived from this software
* without specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY THE INSTITUTE AND CONTRIBUTORS ``AS IS'' AND
* ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
* ARE DISCLAIMED. IN NO EVENT SHALL THE INSTITUTE OR CONTRIBUTORS BE LIABLE
* FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
* DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
* OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
* HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
* LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
* OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
* SUCH DAMAGE.
*/
#include "krb5_locl.h"
#include "store-int.h"
RCSID("$Id: store_mem.c,v 1.11 2002/04/18 14:00:44 joda Exp $");
typedef struct mem_storage{
unsigned char *base;
size_t size;
unsigned char *ptr;
}mem_storage;
static ssize_t
mem_fetch(krb5_storage *sp, void *data, size_t size)
{
mem_storage *s = (mem_storage*)sp->data;
if(size > s->base + s->size - s->ptr)
size = s->base + s->size - s->ptr;
memmove(data, s->ptr, size);
sp->seek(sp, size, SEEK_CUR);
return size;
}
static ssize_t
mem_store(krb5_storage *sp, const void *data, size_t size)
{
mem_storage *s = (mem_storage*)sp->data;
if(size > s->base + s->size - s->ptr)
size = s->base + s->size - s->ptr;
memmove(s->ptr, data, size);
sp->seek(sp, size, SEEK_CUR);
return size;
}
static off_t
mem_seek(krb5_storage *sp, off_t offset, int whence)
{
mem_storage *s = (mem_storage*)sp->data;
switch(whence){
case SEEK_SET:
if(offset > s->size)
offset = s->size;
if(offset < 0)
offset = 0;
s->ptr = s->base + offset;
break;
case SEEK_CUR:
return sp->seek(sp, s->ptr - s->base + offset, SEEK_SET);
case SEEK_END:
return sp->seek(sp, s->size + offset, SEEK_SET);
default:
errno = EINVAL;
return -1;
}
return s->ptr - s->base;
}
krb5_storage *
krb5_storage_from_mem(void *buf, size_t len)
{
krb5_storage *sp = malloc(sizeof(krb5_storage));
mem_storage *s;
if(sp == NULL)
return NULL;
s = malloc(sizeof(*s));
if(s == NULL) {
free(sp);
return NULL;
}
sp->data = s;
sp->flags = 0;
sp->eof_code = HEIM_ERR_EOF;
s->base = buf;
s->size = len;
s->ptr = buf;
sp->fetch = mem_fetch;
sp->store = mem_store;
sp->seek = mem_seek;
sp->free = NULL;
return sp;
}
krb5_storage *
krb5_storage_from_data(krb5_data *data)
{
return krb5_storage_from_mem(data->data, data->length);
}