summaryrefslogtreecommitdiff
path: root/usr.sbin/snmpd/util.c
blob: 26a83bec45990e49ab14e9039a9d85c3a41cdba1 (plain)
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
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
/*	$OpenBSD: util.c,v 1.10 2020/06/30 17:11:49 martijn Exp $	*/
/*
 * Copyright (c) 2014 Bret Stephen Lambert <blambert@openbsd.org>
 *
 * Permission to use, copy, modify, and distribute this software for any
 * purpose with or without fee is hereby granted, provided that the above
 * copyright notice and this permission notice appear in all copies.
 *
 * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
 * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
 * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
 * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
 * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
 * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
 * OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
 */

#include <sys/types.h>
#include <sys/queue.h>
#include <sys/socket.h>

#include <net/if.h>

#include <ber.h>
#include <stdio.h>
#include <string.h>
#include <netdb.h>
#include <event.h>

#include "snmp.h"
#include "snmpd.h"

ssize_t
sendtofrom(int s, void *buf, size_t len, int flags, struct sockaddr *to,
    socklen_t tolen, struct sockaddr *from, socklen_t fromlen)
{
	struct iovec		 iov;
	struct msghdr		 msg;
	struct cmsghdr		*cmsg;
	struct in6_pktinfo	*pkt6;
	struct sockaddr_in	*in;
	struct sockaddr_in6	*in6;
	union {
		struct cmsghdr	hdr;
		char		inbuf[CMSG_SPACE(sizeof(struct in_addr))];
		char		in6buf[CMSG_SPACE(sizeof(struct in6_pktinfo))];
	} cmsgbuf;

	bzero(&msg, sizeof(msg));
	bzero(&cmsgbuf, sizeof(cmsgbuf));

	iov.iov_base = buf;
	iov.iov_len = len;
	msg.msg_iov = &iov;
	msg.msg_iovlen = 1;
	msg.msg_name = to;
	msg.msg_namelen = tolen;
	msg.msg_control = &cmsgbuf;
	msg.msg_controllen = sizeof(cmsgbuf);

	cmsg = CMSG_FIRSTHDR(&msg);
	switch (to->sa_family) {
	case AF_INET:
		msg.msg_controllen = sizeof(cmsgbuf.inbuf);
		cmsg->cmsg_len = CMSG_LEN(sizeof(struct in_addr));
		cmsg->cmsg_level = IPPROTO_IP;
		cmsg->cmsg_type = IP_SENDSRCADDR;
		in = (struct sockaddr_in *)from;
		memcpy(CMSG_DATA(cmsg), &in->sin_addr, sizeof(struct in_addr));
		break;
	case AF_INET6:
		msg.msg_controllen = sizeof(cmsgbuf.in6buf);
		cmsg->cmsg_len = CMSG_LEN(sizeof(struct in6_pktinfo));
		cmsg->cmsg_level = IPPROTO_IPV6;
		cmsg->cmsg_type = IPV6_PKTINFO;
		in6 = (struct sockaddr_in6 *)from;
		pkt6 = (struct in6_pktinfo *)CMSG_DATA(cmsg);
		pkt6->ipi6_addr = in6->sin6_addr;
		break;
	}

	return sendmsg(s, &msg, flags);
}

ssize_t
recvfromto(int s, void *buf, size_t len, int flags, struct sockaddr *from,
    socklen_t *fromlen, struct sockaddr *to, socklen_t *tolen)
{
	struct iovec		 iov;
	struct msghdr		 msg;
	struct cmsghdr		*cmsg;
	struct in6_pktinfo	*pkt6;
	struct sockaddr_in	*in;
	struct sockaddr_in6	*in6;
	ssize_t			 ret;
	union {
		struct cmsghdr hdr;
		char	buf[CMSG_SPACE(sizeof(struct sockaddr_storage))];
	} cmsgbuf;

	bzero(&msg, sizeof(msg));
	bzero(&cmsgbuf.buf, sizeof(cmsgbuf.buf));

	iov.iov_base = buf;
	iov.iov_len = len;
	msg.msg_iov = &iov;
	msg.msg_iovlen = 1;
	msg.msg_name = from;
	msg.msg_namelen = *fromlen;
	msg.msg_control = &cmsgbuf.buf;
	msg.msg_controllen = sizeof(cmsgbuf.buf);

	if ((ret = recvmsg(s, &msg, flags)) == -1)
		return (-1);

	*fromlen = from->sa_len;
	*tolen = 0;

	if (getsockname(s, to, tolen) != 0)
		*tolen = 0;

	for (cmsg = CMSG_FIRSTHDR(&msg); cmsg != NULL;
	    cmsg = CMSG_NXTHDR(&msg, cmsg)) {
		switch (from->sa_family) {
		case AF_INET:
			if (cmsg->cmsg_level == IPPROTO_IP &&
			    cmsg->cmsg_type == IP_RECVDSTADDR) {
				in = (struct sockaddr_in *)to;
				in->sin_family = AF_INET;
				in->sin_len = *tolen = sizeof(*in);
				memcpy(&in->sin_addr, CMSG_DATA(cmsg),
				    sizeof(struct in_addr));
			}
			break;
		case AF_INET6:
			if (cmsg->cmsg_level == IPPROTO_IPV6 &&
			    cmsg->cmsg_type == IPV6_PKTINFO) {
				in6 = (struct sockaddr_in6 *)to;
				in6->sin6_family = AF_INET6;
				in6->sin6_len = *tolen = sizeof(*in6);
				pkt6 = (struct in6_pktinfo *)CMSG_DATA(cmsg);
				memcpy(&in6->sin6_addr, &pkt6->ipi6_addr,
				    sizeof(struct in6_addr));
				if (IN6_IS_ADDR_LINKLOCAL(&in6->sin6_addr))
					in6->sin6_scope_id =
					    pkt6->ipi6_ifindex;
			}
			break;
		}
	}

	return (ret);
}

void
print_debug(const char *emsg, ...)
{
	va_list	 ap;

	if (log_getverbose() > 2) {
		va_start(ap, emsg);
		vfprintf(stderr, emsg, ap);
		va_end(ap);
	}
}

void
print_verbose(const char *emsg, ...)
{
	va_list	 ap;

	if (log_getverbose()) {
		va_start(ap, emsg);
		vfprintf(stderr, emsg, ap);
		va_end(ap);
	}
}

const char *
log_in6addr(const struct in6_addr *addr)
{
	static char		buf[NI_MAXHOST];
	struct sockaddr_in6	sa_in6;
	u_int16_t		tmp16;

	bzero(&sa_in6, sizeof(sa_in6));
	sa_in6.sin6_len = sizeof(sa_in6);
	sa_in6.sin6_family = AF_INET6;
	memcpy(&sa_in6.sin6_addr, addr, sizeof(sa_in6.sin6_addr));

	/* XXX thanks, KAME, for this ugliness... adopted from route/show.c */
	if (IN6_IS_ADDR_LINKLOCAL(&sa_in6.sin6_addr) ||
	    IN6_IS_ADDR_MC_LINKLOCAL(&sa_in6.sin6_addr)) {
		memcpy(&tmp16, &sa_in6.sin6_addr.s6_addr[2], sizeof(tmp16));
		sa_in6.sin6_scope_id = ntohs(tmp16);
		sa_in6.sin6_addr.s6_addr[2] = 0;
		sa_in6.sin6_addr.s6_addr[3] = 0;
	}

	return (print_host((struct sockaddr_storage *)&sa_in6, buf,
	    NI_MAXHOST));
}

const char *
print_host(struct sockaddr_storage *ss, char *buf, size_t len)
{
	if (getnameinfo((struct sockaddr *)ss, ss->ss_len,
	    buf, len, NULL, 0, NI_NUMERICHOST) != 0) {
		buf[0] = '\0';
		return (NULL);
	}
	return (buf);
}