1 /* ----------------------------------------------------------------------- *
2 *
3 * Copyright 2007-2008 H. Peter Anvin - All Rights Reserved
4 *
5 * Permission is hereby granted, free of charge, to any person
6 * obtaining a copy of this software and associated documentation
7 * files (the "Software"), to deal in the Software without
8 * restriction, including without limitation the rights to use,
9 * copy, modify, merge, publish, distribute, sublicense, and/or
10 * sell copies of the Software, and to permit persons to whom
11 * the Software is furnished to do so, subject to the following
12 * conditions:
13 *
14 * The above copyright notice and this permission notice shall
15 * be included in all copies or substantial portions of the Software.
16 *
17 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
18 * EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES
19 * OF MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
20 * NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT
21 * HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY,
22 * WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
23 * FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR
24 * OTHER DEALINGS IN THE SOFTWARE.
25 *
26 * ----------------------------------------------------------------------- */
27
28 /*
29 * pxe_get_cached.c
30 *
31 * PXE call "get cached info"
32 */
33
34 #include <stdlib.h>
35 #include <stdint.h>
36 #include <string.h>
37 #include <com32.h>
38
39 #include <syslinux/pxe.h>
40
41 /* Returns the status code from PXE (0 on success),
42 or -1 on invocation failure */
pxe_get_cached_info(int level,void ** buf,size_t * len)43 int pxe_get_cached_info(int level, void **buf, size_t * len)
44 {
45 const int max_dhcp_packet = 2048;
46 t_PXENV_GET_CACHED_INFO *gci;
47 void *bbuf, *nbuf;
48 int err;
49
50 gci = lmalloc(sizeof *gci + max_dhcp_packet);
51 if (!gci)
52 return -1;
53
54 bbuf = &gci[1];
55
56 gci->Status = PXENV_STATUS_FAILURE;
57 gci->PacketType = level;
58 gci->BufferSize = gci->BufferLimit = max_dhcp_packet;
59 gci->Buffer.seg = SEG(bbuf);
60 gci->Buffer.offs = OFFS(bbuf);
61
62 err = pxe_call(PXENV_GET_CACHED_INFO, gci);
63
64 if (err) {
65 err = -1;
66 goto exit;
67 }
68
69 if (gci->Status) {
70 err = gci->Status;
71 goto exit;
72 }
73
74 nbuf = malloc(gci->BufferSize);
75 if (!nbuf) {
76 err = -1;
77 goto exit;
78 }
79
80 memcpy(nbuf, bbuf, gci->BufferSize);
81
82 *buf = nbuf;
83 *len = gci->BufferSize;
84 err = 0;
85
86 exit:
87 lfree(gci);
88 return err;
89 }
90