1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
|
/* $Id: getrawsock.c $ */
/** @file
* Obtain raw-sockets from a server when debugging unprivileged.
*/
/*
* Copyright (C) 2013-2023 Oracle and/or its affiliates.
*
* This file is part of VirtualBox base platform packages, as
* available from https://www.virtualbox.org.
*
* This program is free software; you can redistribute it and/or
* modify it under the terms of the GNU General Public License
* as published by the Free Software Foundation, in version 3 of the
* License.
*
* This program is distributed in the hope that it will be useful, but
* WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
* General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* along with this program; if not, see <https://www.gnu.org/licenses>.
*
* SPDX-License-Identifier: GPL-3.0-only
*/
#include <sys/types.h>
#include <sys/socket.h>
#include <sys/un.h>
#include <netinet/in.h>
#include <errno.h>
#include <pwd.h>
#include <signal.h>
#include <stdio.h>
#include <string.h>
#include <unistd.h>
/* XXX: this should be in a header, but isn't. naughty me. :( */
int getrawsock(int type);
int
getrawsock(int type)
{
struct sockaddr_un sux; /* because solaris */
struct passwd *pw;
size_t pathlen;
int rawsock, server;
struct msghdr mh;
struct iovec iov[1];
char buf[1];
struct cmsghdr *cmh;
char cmsg[CMSG_SPACE(sizeof(int))];
ssize_t nread, nsent;
int status;
server = -1;
rawsock = -1;
memset(&sux, 0, sizeof(sux));
sux.sun_family = AF_UNIX;
if (geteuid() == 0) {
return -1;
}
if (type == AF_INET) {
buf[0] = '4';
}
else if (type == AF_INET6) {
buf[0] = '6';
}
else {
return -1;
}
errno = 0;
pw = getpwuid(getuid());
if (pw == NULL) {
perror("getpwuid");
return -1;
}
pathlen = snprintf(sux.sun_path, sizeof(sux.sun_path),
"/tmp/.vbox-%s-aux/mkrawsock", pw->pw_name);
if (pathlen > sizeof(sux.sun_path)) {
fprintf(stderr, "socket pathname truncated\n");
return -1;
}
server = socket(PF_UNIX, SOCK_STREAM, 0);
if (server < 0) {
perror("socket");
return -1;
}
status = connect(server, (struct sockaddr *)&sux,
(sizeof(sux) - sizeof(sux.sun_path)
+ strlen(sux.sun_path) + 1));
if (status < 0) {
perror(sux.sun_path);
goto out;
}
nsent = send(server, buf, 1, 0);
if (nsent != 1) {
if (nsent < 0) {
perror("send");
}
else {
fprintf(stderr, "failed to contact mkrawsock\n");
}
goto out;
}
buf[0] = '\0';
iov[0].iov_base = buf;
iov[0].iov_len = 1;
memset(&mh, 0, sizeof(mh));
mh.msg_iov = iov;
mh.msg_iovlen = 1;
mh.msg_control = cmsg;
mh.msg_controllen = sizeof(cmsg);
nread = recvmsg(server, &mh, 0);
if (nread != 1) {
if (nread < 0) {
perror("recvmsg");
}
else {
fprintf(stderr, "EOF from mkrawsock\n");
}
goto out;
}
if ((type == AF_INET && buf[0] != '4')
|| (type == AF_INET6 && buf[0] != '6')
|| mh.msg_controllen == 0)
{
goto out;
}
for (cmh = CMSG_FIRSTHDR(&mh); cmh != NULL; cmh = CMSG_NXTHDR(&mh, cmh)) {
if ((cmh->cmsg_level == SOL_SOCKET)
&& (cmh->cmsg_type == SCM_RIGHTS)
&& (cmh->cmsg_len == CMSG_LEN(sizeof(rawsock))))
{
rawsock = *((int *)CMSG_DATA(cmh));
break;
}
}
out:
if (server != -1) {
close(server);
}
if (rawsock != -1) {
printf("%s: got ICMPv%c socket %d\n",
__func__, type == AF_INET ? '4' : '6', rawsock);
}
return rawsock;
}
|
