lib/krb5/store_fd.c

   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     return sp;
 132 }