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(size: 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(v: &pd->appcnt, i: 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(objp: 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(objp: 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(p: 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, len: sizeof(_iph), buffer: &_iph);
224 if (ih == NULL)
225 sprintf(buf, fmt: "TRUNCATED");
226 else if (ih->frag_off & htons(IP_OFFSET))
227 sprintf(buf, fmt: "%pI4->%pI4 frag", &ih->saddr, &ih->daddr);
228 else {
229 __be16 _ports[2], *pptr;
230
231 pptr = skb_header_pointer(skb, offset: offset + ih->ihl*4,
232 len: sizeof(_ports), buffer: _ports);
233 if (pptr == NULL)
234 sprintf(buf, fmt: "TRUNCATED %pI4->%pI4",
235 &ih->saddr, &ih->daddr);
236 else
237 sprintf(buf, fmt: "%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, len: sizeof(_iph), buffer: &_iph);
256 if (ih == NULL)
257 sprintf(buf, fmt: "TRUNCATED");
258 else if (ih->nexthdr == IPPROTO_FRAGMENT)
259 sprintf(buf, fmt: "%pI6c->%pI6c frag", &ih->saddr, &ih->daddr);
260 else {
261 __be16 _ports[2], *pptr;
262
263 pptr = skb_header_pointer(skb, offset: offset + sizeof(struct ipv6hdr),
264 len: sizeof(_ports), buffer: _ports);
265 if (pptr == NULL)
266 sprintf(buf, fmt: "TRUNCATED %pI6c->%pI6c",
267 &ih->saddr, &ih->daddr);
268 else
269 sprintf(buf, fmt: "%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, pp: 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

source code of linux/net/netfilter/ipvs/ip_vs_proto.c