libipt_CLUSTERIP.c revision c340f6c3020d10975241662d449046eb4ca7a020
1/* Shared library add-on to iptables to add CLUSTERIP target support.
2 * (C) 2003 by Harald Welte <laforge@gnumonks.org>
3 *
4 * Development of this code was funded by SuSE AG, http://www.suse.com/
5 */
6#include <stdio.h>
7#include <string.h>
8#include <stdlib.h>
9#include <getopt.h>
10
11#if defined(__GLIBC__) && __GLIBC__ == 2
12#include <net/ethernet.h>
13#else
14#include <linux/if_ether.h>
15#endif
16
17#include <iptables.h>
18#include <linux/netfilter_ipv4/ip_tables.h>
19#include <linux/netfilter_ipv4/ipt_CLUSTERIP.h>
20
21static void
22help(void)
23{
24	printf(
25"CLUSTERIP target v%s options:\n"
26"  --new			 Create a new ClusterIP\n"
27"  --hashmode <mode>		 Specify hashing mode\n"
28"					sourceip\n"
29"					sourceip-sourceport\n"
30"					sourceip-sourceport-destport\n"
31"  --clustermac <mac>		 Set clusterIP MAC address\n"
32"  --total-nodes <num>		 Set number of total nodes in cluster\n"
33"  --local-node <num>		 Set the local node number\n"
34"  --hash-init\n"
35"\n",
36IPTABLES_VERSION);
37}
38
39static struct option opts[] = {
40	{ "new", 0, 0, '1' },
41	{ "hashmode", 1, 0, '2' },
42	{ "clustermac", 1, 0, '3' },
43	{ "total-nodes", 1, 0, '4' },
44	{ "local-node", 1, 0, '5' },
45	{ 0 }
46};
47
48static void
49init(struct ipt_entry_target *t, unsigned int *nfcache)
50{
51}
52
53static void
54parse_mac(const char *mac, char *macbuf)
55{
56	unsigned int i = 0;
57
58	if (strlen(mac) != ETH_ALEN*3-1)
59		exit_error(PARAMETER_PROBLEM, "Bad mac address `%s'", mac);
60
61	for (i = 0; i < ETH_ALEN; i++) {
62		long number;
63		char *end;
64
65		number = strtol(mac + i*3, &end, 16);
66
67		if (end == mac + i*3 + 2
68		    && number >= 0
69		    && number <= 255)
70			macbuf[i] = number;
71		else
72			exit_error(PARAMETER_PROBLEM,
73				   "Bad mac address `%s'", mac);
74	}
75}
76
77#define	PARAM_NEW	0x0001
78#define PARAM_HMODE	0x0002
79#define PARAM_MAC	0x0004
80#define PARAM_TOTALNODE	0x0008
81#define PARAM_LOCALNODE	0x0010
82
83static int
84parse(int c, char **argv, int invert, unsigned int *flags,
85      const struct ipt_entry *entry,
86      struct ipt_entry_target **target)
87{
88	struct ipt_clusterip_tgt_info *cipinfo
89		= (struct ipt_clusterip_tgt_info *)(*target)->data;
90
91	switch (c) {
92		unsigned int num;
93	case '1':
94		cipinfo->flags |= CLUSTERIP_FLAG_NEW;
95		if (*flags & PARAM_NEW)
96			exit_error(PARAMETER_PROBLEM, "Can only specify `--new' once\n");
97		*flags |= PARAM_NEW;
98		break;
99	case '2':
100		if (!(*flags & PARAM_NEW))
101			exit_error(PARAMETER_PROBLEM, "Can only specify hashmode combined with `--new'\n");
102		if (*flags & PARAM_HMODE)
103			exit_error(PARAMETER_PROBLEM, "Can only specify hashmode once\n");
104		if (!strcmp(optarg, "sourceip"))
105			cipinfo->hash_mode = CLUSTERIP_HASHMODE_SIP;
106		else if (!strcmp(optarg, "sourceip-sourceport"))
107			cipinfo->hash_mode = CLUSTERIP_HASHMODE_SIP_SPT;
108		else if (!strcmp(optarg, "sourceip-sourceport-destport"))
109			cipinfo->hash_mode = CLUSTERIP_HASHMODE_SIP_SPT_DPT;
110		else
111			exit_error(PARAMETER_PROBLEM, "Unknown hashmode `%s'\n",
112				   optarg);
113		*flags |= PARAM_HMODE;
114		break;
115	case '3':
116		if (!(*flags & PARAM_NEW))
117			exit_error(PARAMETER_PROBLEM, "Can only specify MAC combined with `--new'\n");
118		if (*flags & PARAM_MAC)
119			exit_error(PARAMETER_PROBLEM, "Can only specify MAC once\n");
120		parse_mac(optarg, cipinfo->clustermac);
121		*flags |= PARAM_MAC;
122		break;
123	case '4':
124		if (!(*flags & PARAM_NEW))
125			exit_error(PARAMETER_PROBLEM, "Can only specify node number combined with `--new'\n");
126		if (*flags & PARAM_TOTALNODE)
127			exit_error(PARAMETER_PROBLEM, "Can only specify total node number once\n");
128		if (string_to_number(optarg, 1, CLUSTERIP_MAX_NODES, &num) < 0)
129			exit_error(PARAMETER_PROBLEM, "Unable to parse `%s'\n", optarg);
130		cipinfo->num_total_nodes = (u_int16_t)num;
131		*flags |= PARAM_TOTALNODE;
132		break;
133	case '5':
134		if (!(*flags & PARAM_NEW))
135			exit_error(PARAMETER_PROBLEM, "Can only specify node number combined with `--new'\n");
136		if (*flags & PARAM_LOCALNODE)
137			exit_error(PARAMETER_PROBLEM, "Can only specify local node number once\n");
138		if (string_to_number(optarg, 1, CLUSTERIP_MAX_NODES, &num) < 0)
139			exit_error(PARAMETER_PROBLEM, "Unable to parse `%s'\n", optarg);
140		cipinfo->num_local_nodes = 1;
141		cipinfo->local_nodes[0] = (u_int16_t)num;
142		*flags |= PARAM_LOCALNODE;
143		break;
144	default:
145		return 0;
146	}
147
148	return 1;
149}
150
151static void
152final_check(unsigned int flags)
153{
154	if (flags == 0)
155		return;
156
157	if (flags == (PARAM_NEW|PARAM_HMODE|PARAM_MAC|PARAM_TOTALNODE|PARAM_LOCALNODE))
158		return;
159
160	exit_error(PARAMETER_PROBLEM, "CLUSTERIP target: Invalid parameter combination\n");
161}
162
163static char *hashmode2str(enum clusterip_hashmode mode)
164{
165	char *retstr;
166	switch (mode) {
167		case CLUSTERIP_HASHMODE_SIP:
168			retstr = "sourceip";
169			break;
170		case CLUSTERIP_HASHMODE_SIP_SPT:
171			retstr = "sourceip-sourceport";
172			break;
173		case CLUSTERIP_HASHMODE_SIP_SPT_DPT:
174			retstr = "sourceip-sourceport-destport";
175			break;
176		default:
177			retstr = "unknown-error";
178			break;
179	}
180	return retstr;
181}
182
183static char *mac2str(u_int8_t mac[ETH_ALEN])
184{
185	static char buf[ETH_ALEN*3];
186	sprintf(buf, "%02X:%02X:%02X:%02X:%02X:%02X",
187		mac[0], mac[1], mac[2], mac[3], mac[4], mac[5]);
188	return buf;
189}
190
191
192/* Prints out the targinfo. */
193static void
194print(const struct ipt_ip *ip,
195      const struct ipt_entry_target *target,
196      int numeric)
197{
198	const struct ipt_clusterip_tgt_info *cipinfo =
199		(const struct ipt_clusterip_tgt_info *)target->data;
200
201	if (!cipinfo->flags & CLUSTERIP_FLAG_NEW) {
202		printf("CLUSTERIP");
203		return;
204	}
205
206	printf("CLUSTERIP hashmode=%s clustermac=%s total_nodes=%u local_node=%u ",
207		hashmode2str(cipinfo->hash_mode),
208		mac2str(cipinfo->clustermac),
209		cipinfo->num_total_nodes,
210		cipinfo->local_nodes[0]);
211}
212
213/* Saves the union ipt_targinfo in parsable form to stdout. */
214static void
215save(const struct ipt_ip *ip, const struct ipt_entry_target *target)
216{
217	/*
218	const struct ipt_connmark_target_info *markinfo =
219		(const struct ipt_connmark_target_info *)target->data;
220
221	switch (markinfo->mode) {
222	case IPT_CONNMARK_SET:
223	    printf("--set-mark 0x%lx ", markinfo->mark);
224	    break;
225	case IPT_CONNMARK_SAVE:
226	    printf("--save-mark ");
227	    break;
228	case IPT_CONNMARK_RESTORE:
229	    printf("--restore-mark ");
230	    break;
231	default:
232	    printf("ERROR: UNKNOWN CONNMARK MODE ");
233	    break;
234	}
235	*/
236}
237
238static
239struct iptables_target clusterip
240= { NULL,
241    "CLUSTERIP",
242    IPTABLES_VERSION,
243    IPT_ALIGN(sizeof(struct ipt_clusterip_tgt_info)),
244    IPT_ALIGN(sizeof(struct ipt_clusterip_tgt_info)),
245    &help,
246    &init,
247    &parse,
248    &final_check,
249    &print,
250    &save,
251    opts
252};
253
254void _init(void)
255{
256	register_target(&clusterip);
257}
258