kmem.c revision 369186 
1/*	$FreeBSD: stable/11/contrib/ipfilter/lib/kmem.c 369186 2021-01-31 04:32:46Z cy $	*/
2
3/*
4 * Copyright (C) 2012 by Darren Reed.
5 *
6 * See the IPFILTER.LICENCE file for details on licencing.
7 */
8/*
9 * kmemcpy() - copies n bytes from kernel memory into user buffer.
10 * returns 0 on success, -1 on error.
11 */
12
13#include <stdio.h>
14#include <sys/param.h>
15#include <sys/types.h>
16#include <sys/uio.h>
17#include <unistd.h>
18#include <string.h>
19#include <fcntl.h>
20#include <sys/file.h>
21#include <kvm.h>
22#include <fcntl.h>
23#include <sys/socket.h>
24#include <sys/ioctl.h>
25#include <netinet/in.h>
26#include <arpa/inet.h>
27#include <netinet/in_systm.h>
28#include <netinet/ip.h>
29#include <net/if.h>
30
31#include "kmem.h"
32
33#if !defined(lint)
34static const char sccsid[] = "@(#)kmem.c	1.4 1/12/96 (C) 1992 Darren Reed";
35static const char rcsid[] = "@(#)$Id$";
36#endif
37
38
39
40static	kvm_t	*kvm_f = NULL;
41
42
43int	openkmem(kern, core)
44	char	*kern, *core;
45{
46	kvm_f = kvm_open(kern, core, NULL, O_RDONLY, NULL);
47	if (kvm_f == NULL)
48	    {
49		perror("openkmem:open");
50		return -1;
51	    }
52	return kvm_f != NULL;
53}
54
55int	kmemcpy(buf, pos, n)
56	register char	*buf;
57	long	pos;
58	register int	n;
59{
60	register int	r;
61
62	if (!n)
63		return 0;
64
65	if (kvm_f == NULL)
66		if (openkmem(NULL, NULL) == -1)
67			return -1;
68
69	while ((r = kvm_read(kvm_f, pos, buf, n)) < n)
70		if (r <= 0)
71		    {
72			fprintf(stderr, "pos=0x%lx ", (u_long)pos);
73			perror("kmemcpy:read");
74			return -1;
75		    }
76		else
77		    {
78			buf += r;
79			pos += r;
80			n -= r;
81		    }
82	return 0;
83}
84
85int	kstrncpy(buf, pos, n)
86	register char	*buf;
87	long	pos;
88	register int	n;
89{
90	register int	r;
91
92	if (!n)
93		return 0;
94
95	if (kvm_f == NULL)
96		if (openkmem(NULL, NULL) == -1)
97			return -1;
98
99	while (n > 0)
100	    {
101		r = kvm_read(kvm_f, pos, buf, 1);
102		if (r <= 0)
103		    {
104			fprintf(stderr, "pos=0x%lx ", (u_long)pos);
105			perror("kmemcpy:read");
106			return -1;
107		    }
108		else
109		    {
110			if (*buf == '\0')
111				break;
112			buf++;
113			pos++;
114			n--;
115		    }
116	    }
117	return 0;
118}
119