xref: /freebsd/crypto/heimdal/lib/krb5/store_fd.c (revision f39bffc62c1395bde25d152c7f68fdf7cbaab414)
1 /*
2  * Copyright (c) 1997 - 2004 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 fd_storage {
38     int fd;
39 } fd_storage;
40 
41 #define FD(S) (((fd_storage*)(S)->data)->fd)
42 
43 static ssize_t
44 fd_fetch(krb5_storage * sp, void *data, size_t size)
45 {
46     return net_read(FD(sp), data, size);
47 }
48 
49 static ssize_t
50 fd_store(krb5_storage * sp, const void *data, size_t size)
51 {
52     return net_write(FD(sp), data, size);
53 }
54 
55 static off_t
56 fd_seek(krb5_storage * sp, off_t offset, int whence)
57 {
58     return lseek(FD(sp), offset, whence);
59 }
60 
61 static int
62 fd_trunc(krb5_storage * sp, off_t offset)
63 {
64     if (ftruncate(FD(sp), offset) == -1)
65 	return errno;
66     return 0;
67 }
68 
69 static void
70 fd_free(krb5_storage * sp)
71 {
72     close(FD(sp));
73 }
74 
75 /**
76  *
77  *
78  * @return A krb5_storage on success, or NULL on out of memory error.
79  *
80  * @ingroup krb5_storage
81  *
82  * @sa krb5_storage_emem()
83  * @sa krb5_storage_from_mem()
84  * @sa krb5_storage_from_readonly_mem()
85  * @sa krb5_storage_from_data()
86  */
87 
88 KRB5_LIB_FUNCTION krb5_storage * KRB5_LIB_CALL
89 krb5_storage_from_fd(krb5_socket_t fd_in)
90 {
91     krb5_storage *sp;
92     int fd;
93 
94 #ifdef SOCKET_IS_NOT_AN_FD
95 #ifdef _MSC_VER
96     if (_get_osfhandle(fd_in) != -1) {
97 	fd = dup(fd_in);
98     } else {
99 	fd = _open_osfhandle(fd_in, 0);
100     }
101 #else
102 #error Dont know how to deal with fd that may or may not be a socket.
103 #endif
104 #else  /* SOCKET_IS_NOT_AN_FD */
105     fd = dup(fd_in);
106 #endif
107 
108     if (fd < 0)
109 	return NULL;
110 
111     sp = malloc(sizeof(krb5_storage));
112     if (sp == NULL) {
113 	close(fd);
114 	return NULL;
115     }
116 
117     sp->data = malloc(sizeof(fd_storage));
118     if (sp->data == NULL) {
119 	close(fd);
120 	free(sp);
121 	return NULL;
122     }
123     sp->flags = 0;
124     sp->eof_code = HEIM_ERR_EOF;
125     FD(sp) = fd;
126     sp->fetch = fd_fetch;
127     sp->store = fd_store;
128     sp->seek = fd_seek;
129     sp->trunc = fd_trunc;
130     sp->free = fd_free;
131     sp->max_alloc = UINT_MAX/8;
132     return sp;
133 }
134