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 */
43int 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
86exit:
87    lfree(gci);
88    return err;
89}
90