1// SPDX-License-Identifier: GPL-2.0-or-later
2/*
3 * ip_vs_proto.c: transport protocol load balancing support for IPVS
4 *
5 * Authors:     Wensong Zhang <wensong@linuxvirtualserver.org>
6 *              Julian Anastasov <ja@ssi.bg>
7 *
8 * Changes:
9 */
10
11#define KMSG_COMPONENT "IPVS"
12#define pr_fmt(fmt) KMSG_COMPONENT ": " fmt
13
14#include <linux/module.h>
15#include <linux/kernel.h>
16#include <linux/skbuff.h>
17#include <linux/gfp.h>
18#include <linux/in.h>
19#include <linux/ip.h>
20#include <net/protocol.h>
21#include <net/tcp.h>
22#include <net/udp.h>
23#include <linux/stat.h>
24#include <linux/proc_fs.h>
25
26#include <net/ip_vs.h>
27
28
29/*
30 * IPVS protocols can only be registered/unregistered when the ipvs
31 * module is loaded/unloaded, so no lock is needed in accessing the
32 * ipvs protocol table.
33 */
34
35#define IP_VS_PROTO_TAB_SIZE		32	/* must be power of 2 */
36#define IP_VS_PROTO_HASH(proto)		((proto) & (IP_VS_PROTO_TAB_SIZE-1))
37
38static struct ip_vs_protocol *ip_vs_proto_table[IP_VS_PROTO_TAB_SIZE];
39
40/* States for conn templates: NONE or words separated with ",", max 15 chars */
41static const char *ip_vs_ctpl_state_name_table[IP_VS_CTPL_S_LAST] = {
42	[IP_VS_CTPL_S_NONE]			= "NONE",
43	[IP_VS_CTPL_S_ASSURED]			= "ASSURED",
44};
45
46/*
47 *	register an ipvs protocol
48 */
49static int __used __init register_ip_vs_protocol(struct ip_vs_protocol *pp)
50{
51	unsigned int hash = IP_VS_PROTO_HASH(pp->protocol);
52
53	pp->next = ip_vs_proto_table[hash];
54	ip_vs_proto_table[hash] = pp;
55
56	if (pp->init != NULL)
57		pp->init(pp);
58
59	return 0;
60}
61
62/*
63 *	register an ipvs protocols netns related data
64 */
65static int
66register_ip_vs_proto_netns(struct netns_ipvs *ipvs, struct ip_vs_protocol *pp)
67{
68	unsigned int hash = IP_VS_PROTO_HASH(pp->protocol);
69	struct ip_vs_proto_data *pd =
70			kzalloc(sizeof(struct ip_vs_proto_data), GFP_KERNEL);
71
72	if (!pd)
73		return -ENOMEM;
74
75	pd->pp = pp;	/* For speed issues */
76	pd->next = ipvs->proto_data_table[hash];
77	ipvs->proto_data_table[hash] = pd;
78	atomic_set(&pd->appcnt, 0);	/* Init app counter */
79
80	if (pp->init_netns != NULL) {
81		int ret = pp->init_netns(ipvs, pd);
82		if (ret) {
83			/* unlink an free proto data */
84			ipvs->proto_data_table[hash] = pd->next;
85			kfree(pd);
86			return ret;
87		}
88	}
89
90	return 0;
91}
92
93/*
94 *	unregister an ipvs protocol
95 */
96static int unregister_ip_vs_protocol(struct ip_vs_protocol *pp)
97{
98	struct ip_vs_protocol **pp_p;
99	unsigned int hash = IP_VS_PROTO_HASH(pp->protocol);
100
101	pp_p = &ip_vs_proto_table[hash];
102	for (; *pp_p; pp_p = &(*pp_p)->next) {
103		if (*pp_p == pp) {
104			*pp_p = pp->next;
105			if (pp->exit != NULL)
106				pp->exit(pp);
107			return 0;
108		}
109	}
110
111	return -ESRCH;
112}
113
114/*
115 *	unregister an ipvs protocols netns data
116 */
117static int
118unregister_ip_vs_proto_netns(struct netns_ipvs *ipvs, struct ip_vs_proto_data *pd)
119{
120	struct ip_vs_proto_data **pd_p;
121	unsigned int hash = IP_VS_PROTO_HASH(pd->pp->protocol);
122
123	pd_p = &ipvs->proto_data_table[hash];
124	for (; *pd_p; pd_p = &(*pd_p)->next) {
125		if (*pd_p == pd) {
126			*pd_p = pd->next;
127			if (pd->pp->exit_netns != NULL)
128				pd->pp->exit_netns(ipvs, pd);
129			kfree(pd);
130			return 0;
131		}
132	}
133
134	return -ESRCH;
135}
136
137/*
138 *	get ip_vs_protocol object by its proto.
139 */
140struct ip_vs_protocol * ip_vs_proto_get(unsigned short proto)
141{
142	struct ip_vs_protocol *pp;
143	unsigned int hash = IP_VS_PROTO_HASH(proto);
144
145	for (pp = ip_vs_proto_table[hash]; pp; pp = pp->next) {
146		if (pp->protocol == proto)
147			return pp;
148	}
149
150	return NULL;
151}
152EXPORT_SYMBOL(ip_vs_proto_get);
153
154/*
155 *	get ip_vs_protocol object data by netns and proto
156 */
157struct ip_vs_proto_data *
158ip_vs_proto_data_get(struct netns_ipvs *ipvs, unsigned short proto)
159{
160	struct ip_vs_proto_data *pd;
161	unsigned int hash = IP_VS_PROTO_HASH(proto);
162
163	for (pd = ipvs->proto_data_table[hash]; pd; pd = pd->next) {
164		if (pd->pp->protocol == proto)
165			return pd;
166	}
167
168	return NULL;
169}
170EXPORT_SYMBOL(ip_vs_proto_data_get);
171
172/*
173 *	Propagate event for state change to all protocols
174 */
175void ip_vs_protocol_timeout_change(struct netns_ipvs *ipvs, int flags)
176{
177	struct ip_vs_proto_data *pd;
178	int i;
179
180	for (i = 0; i < IP_VS_PROTO_TAB_SIZE; i++) {
181		for (pd = ipvs->proto_data_table[i]; pd; pd = pd->next) {
182			if (pd->pp->timeout_change)
183				pd->pp->timeout_change(pd, flags);
184		}
185	}
186}
187
188
189int *
190ip_vs_create_timeout_table(int *table, int size)
191{
192	return kmemdup(table, size, GFP_KERNEL);
193}
194
195
196const char *ip_vs_state_name(const struct ip_vs_conn *cp)
197{
198	unsigned int state = cp->state;
199	struct ip_vs_protocol *pp;
200
201	if (cp->flags & IP_VS_CONN_F_TEMPLATE) {
202
203		if (state >= IP_VS_CTPL_S_LAST)
204			return "ERR!";
205		return ip_vs_ctpl_state_name_table[state] ? : "?";
206	}
207	pp = ip_vs_proto_get(cp->protocol);
208	if (pp == NULL || pp->state_name == NULL)
209		return (cp->protocol == IPPROTO_IP) ? "NONE" : "ERR!";
210	return pp->state_name(state);
211}
212
213
214static void
215ip_vs_tcpudp_debug_packet_v4(struct ip_vs_protocol *pp,
216			     const struct sk_buff *skb,
217			     int offset,
218			     const char *msg)
219{
220	char buf[128];
221	struct iphdr _iph, *ih;
222
223	ih = skb_header_pointer(skb, offset, sizeof(_iph), &_iph);
224	if (ih == NULL)
225		sprintf(buf, "TRUNCATED");
226	else if (ih->frag_off & htons(IP_OFFSET))
227		sprintf(buf, "%pI4->%pI4 frag", &ih->saddr, &ih->daddr);
228	else {
229		__be16 _ports[2], *pptr;
230
231		pptr = skb_header_pointer(skb, offset + ih->ihl*4,
232					  sizeof(_ports), _ports);
233		if (pptr == NULL)
234			sprintf(buf, "TRUNCATED %pI4->%pI4",
235				&ih->saddr, &ih->daddr);
236		else
237			sprintf(buf, "%pI4:%u->%pI4:%u",
238				&ih->saddr, ntohs(pptr[0]),
239				&ih->daddr, ntohs(pptr[1]));
240	}
241
242	pr_debug("%s: %s %s\n", msg, pp->name, buf);
243}
244
245#ifdef CONFIG_IP_VS_IPV6
246static void
247ip_vs_tcpudp_debug_packet_v6(struct ip_vs_protocol *pp,
248			     const struct sk_buff *skb,
249			     int offset,
250			     const char *msg)
251{
252	char buf[192];
253	struct ipv6hdr _iph, *ih;
254
255	ih = skb_header_pointer(skb, offset, sizeof(_iph), &_iph);
256	if (ih == NULL)
257		sprintf(buf, "TRUNCATED");
258	else if (ih->nexthdr == IPPROTO_FRAGMENT)
259		sprintf(buf, "%pI6c->%pI6c frag", &ih->saddr, &ih->daddr);
260	else {
261		__be16 _ports[2], *pptr;
262
263		pptr = skb_header_pointer(skb, offset + sizeof(struct ipv6hdr),
264					  sizeof(_ports), _ports);
265		if (pptr == NULL)
266			sprintf(buf, "TRUNCATED %pI6c->%pI6c",
267				&ih->saddr, &ih->daddr);
268		else
269			sprintf(buf, "%pI6c:%u->%pI6c:%u",
270				&ih->saddr, ntohs(pptr[0]),
271				&ih->daddr, ntohs(pptr[1]));
272	}
273
274	pr_debug("%s: %s %s\n", msg, pp->name, buf);
275}
276#endif
277
278
279void
280ip_vs_tcpudp_debug_packet(int af, struct ip_vs_protocol *pp,
281			  const struct sk_buff *skb,
282			  int offset,
283			  const char *msg)
284{
285#ifdef CONFIG_IP_VS_IPV6
286	if (af == AF_INET6)
287		ip_vs_tcpudp_debug_packet_v6(pp, skb, offset, msg);
288	else
289#endif
290		ip_vs_tcpudp_debug_packet_v4(pp, skb, offset, msg);
291}
292
293/*
294 * per network name-space init
295 */
296int __net_init ip_vs_protocol_net_init(struct netns_ipvs *ipvs)
297{
298	int i, ret;
299	static struct ip_vs_protocol *protos[] = {
300#ifdef CONFIG_IP_VS_PROTO_TCP
301        &ip_vs_protocol_tcp,
302#endif
303#ifdef CONFIG_IP_VS_PROTO_UDP
304	&ip_vs_protocol_udp,
305#endif
306#ifdef CONFIG_IP_VS_PROTO_SCTP
307	&ip_vs_protocol_sctp,
308#endif
309#ifdef CONFIG_IP_VS_PROTO_AH
310	&ip_vs_protocol_ah,
311#endif
312#ifdef CONFIG_IP_VS_PROTO_ESP
313	&ip_vs_protocol_esp,
314#endif
315	};
316
317	for (i = 0; i < ARRAY_SIZE(protos); i++) {
318		ret = register_ip_vs_proto_netns(ipvs, protos[i]);
319		if (ret < 0)
320			goto cleanup;
321	}
322	return 0;
323
324cleanup:
325	ip_vs_protocol_net_cleanup(ipvs);
326	return ret;
327}
328
329void __net_exit ip_vs_protocol_net_cleanup(struct netns_ipvs *ipvs)
330{
331	struct ip_vs_proto_data *pd;
332	int i;
333
334	/* unregister all the ipvs proto data for this netns */
335	for (i = 0; i < IP_VS_PROTO_TAB_SIZE; i++) {
336		while ((pd = ipvs->proto_data_table[i]) != NULL)
337			unregister_ip_vs_proto_netns(ipvs, pd);
338	}
339}
340
341int __init ip_vs_protocol_init(void)
342{
343	char protocols[64];
344#define REGISTER_PROTOCOL(p)			\
345	do {					\
346		register_ip_vs_protocol(p);	\
347		strcat(protocols, ", ");	\
348		strcat(protocols, (p)->name);	\
349	} while (0)
350
351	protocols[0] = '\0';
352	protocols[2] = '\0';
353#ifdef CONFIG_IP_VS_PROTO_TCP
354	REGISTER_PROTOCOL(&ip_vs_protocol_tcp);
355#endif
356#ifdef CONFIG_IP_VS_PROTO_UDP
357	REGISTER_PROTOCOL(&ip_vs_protocol_udp);
358#endif
359#ifdef CONFIG_IP_VS_PROTO_SCTP
360	REGISTER_PROTOCOL(&ip_vs_protocol_sctp);
361#endif
362#ifdef CONFIG_IP_VS_PROTO_AH
363	REGISTER_PROTOCOL(&ip_vs_protocol_ah);
364#endif
365#ifdef CONFIG_IP_VS_PROTO_ESP
366	REGISTER_PROTOCOL(&ip_vs_protocol_esp);
367#endif
368	pr_info("Registered protocols (%s)\n", &protocols[2]);
369
370	return 0;
371}
372
373
374void ip_vs_protocol_cleanup(void)
375{
376	struct ip_vs_protocol *pp;
377	int i;
378
379	/* unregister all the ipvs protocols */
380	for (i = 0; i < IP_VS_PROTO_TAB_SIZE; i++) {
381		while ((pp = ip_vs_proto_table[i]) != NULL)
382			unregister_ip_vs_protocol(pp);
383	}
384}
385