1 /* $FreeBSD$ */
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 #if !defined(__sgi) && !defined(__hpux) && !defined(__osf__) && !defined(linux) && !defined(_AIX51)
22 #include <kvm.h>
23 #endif
24 #include <fcntl.h>
25 #include <sys/socket.h>
26 #include <sys/ioctl.h>
27 #include <netinet/in.h>
28 #include <arpa/inet.h>
29 #include <netinet/in_systm.h>
30 #include <netinet/ip.h>
31 #include <net/if.h>
32 #if defined(linux) || defined(__osf__) || defined(__sgi) || defined(__hpux)
33 # include <stdlib.h>
34 #endif
35
36 #include "kmem.h"
37
38 #ifndef __STDC__
39 # define const
40 #endif
41
42 #if !defined(lint)
43 static const char sccsid[] = "@(#)kmem.c 1.4 1/12/96 (C) 1992 Darren Reed";
44 static const char rcsid[] = "@(#)$Id$";
45 #endif
46
47
48
49 #if !defined(__sgi) && !defined(__hpux) && !defined(__osf__) && \
50 !defined(linux) && !defined(_AIX51)
51 /*
52 * For all platforms where there is a libkvm and a kvm_t, we use that...
53 */
54 static kvm_t *kvm_f = NULL;
55
56 #else
57 /*
58 *...and for the others (HP-UX, IRIX, Tru64), we have to provide our own.
59 */
60
61 typedef int * kvm_t;
62
63 static kvm_t kvm_f = NULL;
64 static char *kvm_errstr = NULL;
65
66 kvm_t kvm_open __P((char *, char *, char *, int, char *));
67 int kvm_read __P((kvm_t, u_long, char *, size_t));
68
kvm_open(kernel,core,swap,mode,errstr)69 kvm_t kvm_open(kernel, core, swap, mode, errstr)
70 char *kernel, *core, *swap;
71 int mode;
72 char *errstr;
73 {
74 kvm_t k;
75 int fd;
76
77 kvm_errstr = errstr;
78
79 if (core == NULL)
80 core = "/dev/kmem";
81
82 fd = open(core, mode);
83 if (fd == -1)
84 return NULL;
85 k = malloc(sizeof(*k));
86 if (k == NULL)
87 return NULL;
88 *k = fd;
89 return k;
90 }
91
kvm_read(kvm,pos,buffer,size)92 int kvm_read(kvm, pos, buffer, size)
93 kvm_t kvm;
94 u_long pos;
95 char *buffer;
96 size_t size;
97 {
98 int r = 0, left;
99 char *bufp;
100
101 if (lseek(*kvm, pos, 0) == -1) {
102 if (kvm_errstr != NULL) {
103 fprintf(stderr, "%s", kvm_errstr);
104 perror("lseek");
105 }
106 return -1;
107 }
108
109 for (bufp = buffer, left = size; left > 0; bufp += r, left -= r) {
110 r = read(*kvm, bufp, left);
111 #ifdef __osf__
112 /*
113 * Tru64 returns "0" for successful operation, not the number
114 * of bytes read.
115 */
116 if (r == 0)
117 r = left;
118 #endif
119 if (r <= 0)
120 return -1;
121 }
122 return r;
123 }
124 #endif /* !defined(__sgi) && !defined(__hpux) && !defined(__osf__) */
125
openkmem(kern,core)126 int openkmem(kern, core)
127 char *kern, *core;
128 {
129 kvm_f = kvm_open(kern, core, NULL, O_RDONLY, NULL);
130 if (kvm_f == NULL)
131 {
132 perror("openkmem:open");
133 return -1;
134 }
135 return kvm_f != NULL;
136 }
137
kmemcpy(buf,pos,n)138 int kmemcpy(buf, pos, n)
139 register char *buf;
140 long pos;
141 register int n;
142 {
143 register int r;
144
145 if (!n)
146 return 0;
147
148 if (kvm_f == NULL)
149 if (openkmem(NULL, NULL) == -1)
150 return -1;
151
152 while ((r = kvm_read(kvm_f, pos, buf, n)) < n)
153 if (r <= 0)
154 {
155 fprintf(stderr, "pos=0x%lx ", (u_long)pos);
156 perror("kmemcpy:read");
157 return -1;
158 }
159 else
160 {
161 buf += r;
162 pos += r;
163 n -= r;
164 }
165 return 0;
166 }
167
kstrncpy(buf,pos,n)168 int kstrncpy(buf, pos, n)
169 register char *buf;
170 long pos;
171 register int n;
172 {
173 register int r;
174
175 if (!n)
176 return 0;
177
178 if (kvm_f == NULL)
179 if (openkmem(NULL, NULL) == -1)
180 return -1;
181
182 while (n > 0)
183 {
184 r = kvm_read(kvm_f, pos, buf, 1);
185 if (r <= 0)
186 {
187 fprintf(stderr, "pos=0x%lx ", (u_long)pos);
188 perror("kmemcpy:read");
189 return -1;
190 }
191 else
192 {
193 if (*buf == '\0')
194 break;
195 buf++;
196 pos++;
197 n--;
198 }
199 }
200 return 0;
201 }
202