summaryrefslogtreecommitdiff
path: root/ctdb/common/system_common.c
blob: 899f3b56bebc6927089da675997c30362a4d1dc2 (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
/* 
   ctdb system specific code to manage raw sockets on linux

   Copyright (C) Ronnie Sahlberg  2007
   Copyright (C) Andrew Tridgell  2007

   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; either version 3 of the License, or
   (at your option) any later version.
   
   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 <http://www.gnu.org/licenses/>.
*/

#include "includes.h"
#include "system/network.h"

#include "ctdb_private.h"

/*
  uint16 checksum for n bytes
 */
uint32_t uint16_checksum(uint16_t *data, size_t n)
{
	uint32_t sum=0;
	while (n>=2) {
		sum += (uint32_t)ntohs(*data);
		data++;
		n -= 2;
	}
	if (n == 1) {
		sum += (uint32_t)ntohs(*(uint8_t *)data);
	}
	return sum;
}

/*
  see if we currently have an interface with the given IP

  we try to bind to it, and if that fails then we don't have that IP
  on an interface
 */
bool ctdb_sys_have_ip(ctdb_sock_addr *_addr)
{
	int s;
	int ret;
	ctdb_sock_addr __addr = *_addr;
	ctdb_sock_addr *addr = &__addr;
	socklen_t addrlen = 0;

	switch (addr->sa.sa_family) {
	case AF_INET:
		addr->ip.sin_port = 0;
		addrlen = sizeof(struct sockaddr_in);
		break;
	case AF_INET6:
		addr->ip6.sin6_port = 0;
		addrlen = sizeof(struct sockaddr_in6);
		break;
	}

	s = socket(addr->sa.sa_family, SOCK_STREAM, IPPROTO_TCP);
	if (s == -1) {
		return false;
	}

	ret = bind(s, (struct sockaddr *)addr, addrlen);

	close(s);
	return ret == 0;
}


/* find which interface an ip address is currently assigned to */
char *ctdb_sys_find_ifname(ctdb_sock_addr *addr)
{
	int s;
	int size;
	struct ifconf ifc;
	char *ptr;

	s = socket(AF_INET, SOCK_RAW, htons(IPPROTO_RAW));
	if (s == -1) {
		DEBUG(DEBUG_CRIT,(__location__ " failed to open raw socket (%s)\n",
			 strerror(errno)));
		return NULL;
	}


	size = sizeof(struct ifreq);
	ifc.ifc_buf = NULL;
	ifc.ifc_len = size;

	while(ifc.ifc_len > (size - sizeof(struct ifreq))) {
		size *= 2;

		free(ifc.ifc_buf);	
		ifc.ifc_len = size;
		ifc.ifc_buf = malloc(size);
		memset(ifc.ifc_buf, 0, size);
		if (ioctl(s, SIOCGIFCONF, (caddr_t)&ifc) < 0) {
			DEBUG(DEBUG_CRIT,("Failed to read ifc buffer from socket\n"));
			free(ifc.ifc_buf);	
			close(s);
			return NULL;
		}
	}

	for (ptr =(char *)ifc.ifc_buf; ptr < ((char *)ifc.ifc_buf) + ifc.ifc_len; ) {
		char *ifname;
		struct ifreq *ifr;

		ifr = (struct ifreq *)ptr;

#ifdef HAVE_SOCKADDR_LEN
		if (ifr->ifr_addr.sa_len > sizeof(struct sockaddr)) {
			ptr += sizeof(ifr->ifr_name) + ifr->ifr_addr.sa_len;
		} else {
			ptr += sizeof(ifr->ifr_name) + sizeof(struct sockaddr);
		}
#else
		ptr += sizeof(struct ifreq);
#endif

		if (ifr->ifr_addr.sa_family != addr->sa.sa_family) {
			continue;
		}

		switch (addr->sa.sa_family) {
		case AF_INET:


			if (memcmp(&addr->ip.sin_addr, &((struct sockaddr_in *)&ifr->ifr_addr)->sin_addr, sizeof(addr->ip.sin_addr))) {
				continue;
			}
			break;
		case AF_INET6:
			if (memcmp(&addr->ip6.sin6_addr, &((struct sockaddr_in6 *)&ifr->ifr_addr)->sin6_addr, sizeof(addr->ip6.sin6_addr))) {
				continue;
			}
			break;
		}

		ifname = strdup(ifr->ifr_name);
		free(ifc.ifc_buf);	
		close(s);
		return ifname;
	}


	free(ifc.ifc_buf);	
	close(s);

	return NULL;
}