1 /*
2 * Copyright (c) 1997 - 2000, 2002 Kungliga Tekniska Högskolan
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 typedef struct mem_storage{
38 unsigned char *base;
39 size_t size;
40 unsigned char *ptr;
41 }mem_storage;
42
43 static ssize_t
mem_fetch(krb5_storage * sp,void * data,size_t size)44 mem_fetch(krb5_storage *sp, void *data, size_t size)
45 {
46 mem_storage *s = (mem_storage*)sp->data;
47 if(size > (size_t)(s->base + s->size - s->ptr))
48 size = s->base + s->size - s->ptr;
49 memmove(data, s->ptr, size);
50 sp->seek(sp, size, SEEK_CUR);
51 return size;
52 }
53
54 static ssize_t
mem_store(krb5_storage * sp,const void * data,size_t size)55 mem_store(krb5_storage *sp, const void *data, size_t size)
56 {
57 mem_storage *s = (mem_storage*)sp->data;
58 if(size > (size_t)(s->base + s->size - s->ptr))
59 size = s->base + s->size - s->ptr;
60 memmove(s->ptr, data, size);
61 sp->seek(sp, size, SEEK_CUR);
62 return size;
63 }
64
65 static ssize_t
mem_no_store(krb5_storage * sp,const void * data,size_t size)66 mem_no_store(krb5_storage *sp, const void *data, size_t size)
67 {
68 return -1;
69 }
70
71 static off_t
mem_seek(krb5_storage * sp,off_t offset,int whence)72 mem_seek(krb5_storage *sp, off_t offset, int whence)
73 {
74 mem_storage *s = (mem_storage*)sp->data;
75 switch(whence){
76 case SEEK_SET:
77 if((size_t)offset > s->size)
78 offset = s->size;
79 if(offset < 0)
80 offset = 0;
81 s->ptr = s->base + offset;
82 break;
83 case SEEK_CUR:
84 return sp->seek(sp, s->ptr - s->base + offset, SEEK_SET);
85 case SEEK_END:
86 return sp->seek(sp, s->size + offset, SEEK_SET);
87 default:
88 errno = EINVAL;
89 return -1;
90 }
91 return s->ptr - s->base;
92 }
93
94 static int
mem_trunc(krb5_storage * sp,off_t offset)95 mem_trunc(krb5_storage *sp, off_t offset)
96 {
97 mem_storage *s = (mem_storage*)sp->data;
98 if((size_t)offset > s->size)
99 return ERANGE;
100 s->size = offset;
101 if ((s->ptr - s->base) > offset)
102 s->ptr = s->base + offset;
103 return 0;
104 }
105
106 static int
mem_no_trunc(krb5_storage * sp,off_t offset)107 mem_no_trunc(krb5_storage *sp, off_t offset)
108 {
109 return EINVAL;
110 }
111
112 /**
113 * Create a fixed size memory storage block
114 *
115 * @return A krb5_storage on success, or NULL on out of memory error.
116 *
117 * @ingroup krb5_storage
118 *
119 * @sa krb5_storage_mem()
120 * @sa krb5_storage_from_readonly_mem()
121 * @sa krb5_storage_from_data()
122 * @sa krb5_storage_from_fd()
123 */
124
125 KRB5_LIB_FUNCTION krb5_storage * KRB5_LIB_CALL
krb5_storage_from_mem(void * buf,size_t len)126 krb5_storage_from_mem(void *buf, size_t len)
127 {
128 krb5_storage *sp = malloc(sizeof(krb5_storage));
129 mem_storage *s;
130 if(sp == NULL)
131 return NULL;
132 s = malloc(sizeof(*s));
133 if(s == NULL) {
134 free(sp);
135 return NULL;
136 }
137 sp->data = s;
138 sp->flags = 0;
139 sp->eof_code = HEIM_ERR_EOF;
140 s->base = buf;
141 s->size = len;
142 s->ptr = buf;
143 sp->fetch = mem_fetch;
144 sp->store = mem_store;
145 sp->seek = mem_seek;
146 sp->trunc = mem_trunc;
147 sp->free = NULL;
148 sp->max_alloc = UINT_MAX/8;
149 return sp;
150 }
151
152 /**
153 * Create a fixed size memory storage block
154 *
155 * @return A krb5_storage on success, or NULL on out of memory error.
156 *
157 * @ingroup krb5_storage
158 *
159 * @sa krb5_storage_mem()
160 * @sa krb5_storage_from_mem()
161 * @sa krb5_storage_from_readonly_mem()
162 * @sa krb5_storage_from_fd()
163 */
164
165 KRB5_LIB_FUNCTION krb5_storage * KRB5_LIB_CALL
krb5_storage_from_data(krb5_data * data)166 krb5_storage_from_data(krb5_data *data)
167 {
168 return krb5_storage_from_mem(data->data, data->length);
169 }
170
171 /**
172 * Create a fixed size memory storage block that is read only
173 *
174 * @return A krb5_storage on success, or NULL on out of memory error.
175 *
176 * @ingroup krb5_storage
177 *
178 * @sa krb5_storage_mem()
179 * @sa krb5_storage_from_mem()
180 * @sa krb5_storage_from_data()
181 * @sa krb5_storage_from_fd()
182 */
183
184 KRB5_LIB_FUNCTION krb5_storage * KRB5_LIB_CALL
krb5_storage_from_readonly_mem(const void * buf,size_t len)185 krb5_storage_from_readonly_mem(const void *buf, size_t len)
186 {
187 krb5_storage *sp = malloc(sizeof(krb5_storage));
188 mem_storage *s;
189 if(sp == NULL)
190 return NULL;
191 s = malloc(sizeof(*s));
192 if(s == NULL) {
193 free(sp);
194 return NULL;
195 }
196 sp->data = s;
197 sp->flags = 0;
198 sp->eof_code = HEIM_ERR_EOF;
199 s->base = rk_UNCONST(buf);
200 s->size = len;
201 s->ptr = rk_UNCONST(buf);
202 sp->fetch = mem_fetch;
203 sp->store = mem_no_store;
204 sp->seek = mem_seek;
205 sp->trunc = mem_no_trunc;
206 sp->free = NULL;
207 sp->max_alloc = UINT_MAX/8;
208 return sp;
209 }
210