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18#include <linux/config.h>
19#include <linux/module.h>
20#include <linux/types.h>
21#include <linux/kernel.h>
22#include <linux/errno.h>
23#include <net/ip_masq.h>
24#include <net/ip_masq_mod.h>
25
26#include <linux/ip_masq.h>
27#ifdef CONFIG_KMOD
28#include <linux/kmod.h>
29#endif
30
31EXPORT_SYMBOL(register_ip_masq_mod);
32EXPORT_SYMBOL(unregister_ip_masq_mod);
33EXPORT_SYMBOL(ip_masq_mod_lkp_link);
34EXPORT_SYMBOL(ip_masq_mod_lkp_unlink);
35
36#ifdef __SMP__
37static spinlock_t masq_mod_lock = SPIN_LOCK_UNLOCKED;
38#endif
39
40
41
42
43struct ip_masq_mod * ip_masq_mod_reg_base = NULL;
44
45
46
47
48
49
50struct ip_masq_mod * ip_masq_mod_lkp_base = NULL;
51
52int ip_masq_mod_register_proc(struct ip_masq_mod *mmod)
53{
54#ifdef CONFIG_PROC_FS
55 int ret;
56
57 struct proc_dir_entry *ent = mmod->mmod_proc_ent;
58
59 if (!ent)
60 return 0;
61 if (!ent->name) {
62 ent->name = mmod->mmod_name;
63 ent->namelen = strlen (mmod->mmod_name);
64 }
65 ret = ip_masq_proc_register(ent);
66 if (ret) mmod->mmod_proc_ent = NULL;
67
68 return ret;
69#else
70 return 0;
71#endif
72}
73
74void ip_masq_mod_unregister_proc(struct ip_masq_mod *mmod)
75{
76#ifdef CONFIG_PROC_FS
77 struct proc_dir_entry *ent = mmod->mmod_proc_ent;
78 if (!ent)
79 return;
80 ip_masq_proc_unregister(ent);
81#endif
82}
83
84
85
86
87
88int ip_masq_mod_lkp_unlink(struct ip_masq_mod *mmod)
89{
90 struct ip_masq_mod **mmod_p;
91
92 write_lock_bh(&masq_mod_lock);
93
94 for (mmod_p = &ip_masq_mod_lkp_base; *mmod_p ; mmod_p = &(*mmod_p)->next)
95 if (mmod == (*mmod_p)) {
96 *mmod_p = mmod->next;
97 mmod->next = NULL;
98 write_unlock_bh(&masq_mod_lock);
99 return 0;
100 }
101
102 write_unlock_bh(&masq_mod_lock);
103 return -EINVAL;
104}
105
106int ip_masq_mod_lkp_link(struct ip_masq_mod *mmod)
107{
108 write_lock_bh(&masq_mod_lock);
109
110 mmod->next = ip_masq_mod_lkp_base;
111 ip_masq_mod_lkp_base=mmod;
112
113 write_unlock_bh(&masq_mod_lock);
114 return 0;
115}
116
117int register_ip_masq_mod(struct ip_masq_mod *mmod)
118{
119 if (!mmod) {
120 IP_MASQ_ERR("register_ip_masq_mod(): NULL arg\n");
121 return -EINVAL;
122 }
123 if (!mmod->mmod_name) {
124 IP_MASQ_ERR("register_ip_masq_mod(): NULL mmod_name\n");
125 return -EINVAL;
126 }
127 ip_masq_mod_register_proc(mmod);
128
129 mmod->next_reg = ip_masq_mod_reg_base;
130 ip_masq_mod_reg_base=mmod;
131
132 return 0;
133}
134
135int unregister_ip_masq_mod(struct ip_masq_mod *mmod)
136{
137 struct ip_masq_mod **mmod_p;
138
139 if (!mmod) {
140 IP_MASQ_ERR( "unregister_ip_masq_mod(): NULL arg\n");
141 return -EINVAL;
142 }
143
144
145
146
147 if (atomic_read(&mmod->refcnt)) {
148 IP_MASQ_ERR( "unregister_ip_masq_mod(): is in use by %d guys. failed\n",
149 atomic_read(&mmod->refcnt));
150 return -EINVAL;
151 }
152
153
154
155
156 if (mmod->next) {
157 IP_MASQ_WARNING("MASQ: unregistering \"%s\" while in lookup list.fixed.",
158 mmod->mmod_name);
159 ip_masq_mod_lkp_unlink(mmod);
160 }
161
162 for (mmod_p = &ip_masq_mod_reg_base; *mmod_p ; mmod_p = &(*mmod_p)->next_reg)
163 if (mmod == (*mmod_p)) {
164 ip_masq_mod_unregister_proc(mmod);
165 *mmod_p = mmod->next_reg;
166 return 0;
167 }
168
169 IP_MASQ_ERR("unregister_ip_masq_mod(%s): not linked \n", mmod->mmod_name);
170 return -EINVAL;
171}
172
173int ip_masq_mod_in_rule(const struct sk_buff *skb, const struct iphdr *iph)
174{
175 struct ip_masq_mod *mmod;
176 int ret = IP_MASQ_MOD_NOP;
177
178 for (mmod=ip_masq_mod_lkp_base;mmod;mmod=mmod->next) {
179 if (!mmod->mmod_in_rule) continue;
180 switch (ret=mmod->mmod_in_rule(skb, iph)) {
181 case IP_MASQ_MOD_NOP:
182 continue;
183 case IP_MASQ_MOD_ACCEPT:
184 case IP_MASQ_MOD_REJECT:
185 goto out;
186 }
187 }
188out:
189 return ret;
190}
191
192int ip_masq_mod_out_rule(const struct sk_buff *skb, const struct iphdr *iph)
193{
194 struct ip_masq_mod *mmod;
195 int ret = IP_MASQ_MOD_NOP;
196
197 for (mmod=ip_masq_mod_lkp_base;mmod;mmod=mmod->next) {
198 if (!mmod->mmod_out_rule) continue;
199 switch (ret=mmod->mmod_out_rule(skb, iph)) {
200 case IP_MASQ_MOD_NOP:
201 continue;
202 case IP_MASQ_MOD_ACCEPT:
203 case IP_MASQ_MOD_REJECT:
204 goto out;
205 }
206 }
207out:
208 return ret;
209}
210
211struct ip_masq * ip_masq_mod_in_create(const struct sk_buff *skb, const struct iphdr *iph, __u32 maddr)
212{
213 struct ip_masq_mod *mmod;
214 struct ip_masq *ms = NULL;
215
216 for (mmod=ip_masq_mod_lkp_base;mmod;mmod=mmod->next) {
217 if (!mmod->mmod_in_create) continue;
218 if ((ms=mmod->mmod_in_create(skb, iph, maddr))) {
219 goto out;
220 }
221 }
222out:
223 return ms;
224}
225
226struct ip_masq * ip_masq_mod_out_create(const struct sk_buff *skb, const struct iphdr *iph, __u32 maddr)
227{
228 struct ip_masq_mod *mmod;
229 struct ip_masq *ms = NULL;
230
231 for (mmod=ip_masq_mod_lkp_base;mmod;mmod=mmod->next) {
232 if (!mmod->mmod_out_create) continue;
233 if ((ms=mmod->mmod_out_create(skb, iph, maddr))) {
234 goto out;
235 }
236 }
237out:
238 return ms;
239}
240
241int ip_masq_mod_in_update(const struct sk_buff *skb, const struct iphdr *iph, struct ip_masq *ms)
242{
243 struct ip_masq_mod *mmod;
244 int ret = IP_MASQ_MOD_NOP;
245
246 for (mmod=ip_masq_mod_lkp_base;mmod;mmod=mmod->next) {
247 if (!mmod->mmod_in_update) continue;
248 switch (ret=mmod->mmod_in_update(skb, iph, ms)) {
249 case IP_MASQ_MOD_NOP:
250 continue;
251 case IP_MASQ_MOD_ACCEPT:
252 case IP_MASQ_MOD_REJECT:
253 goto out;
254 }
255 }
256out:
257 return ret;
258}
259
260int ip_masq_mod_out_update(const struct sk_buff *skb, const struct iphdr *iph, struct ip_masq *ms)
261{
262 struct ip_masq_mod *mmod;
263 int ret = IP_MASQ_MOD_NOP;
264
265 for (mmod=ip_masq_mod_lkp_base;mmod;mmod=mmod->next) {
266 if (!mmod->mmod_out_update) continue;
267 switch (ret=mmod->mmod_out_update(skb, iph, ms)) {
268 case IP_MASQ_MOD_NOP:
269 continue;
270 case IP_MASQ_MOD_ACCEPT:
271 case IP_MASQ_MOD_REJECT:
272 goto out;
273 }
274 }
275out:
276 return ret;
277}
278
279struct ip_masq_mod * ip_masq_mod_getbyname(const char *mmod_name)
280{
281 struct ip_masq_mod * mmod;
282
283 IP_MASQ_DEBUG(1, "searching mmod_name \"%s\"\n", mmod_name);
284
285 for (mmod=ip_masq_mod_reg_base; mmod ; mmod=mmod->next_reg) {
286 if (mmod->mmod_ctl && *(mmod_name)
287 && (strcmp(mmod_name, mmod->mmod_name)==0)) {
288
289 return mmod;
290 }
291 }
292 return NULL;
293}
294
295
296
297
298int ip_masq_mod_ctl(int optname, struct ip_masq_ctl *mctl, int optlen)
299{
300 struct ip_masq_mod * mmod;
301#ifdef CONFIG_KMOD
302 char kmod_name[IP_MASQ_TNAME_MAX+8];
303#endif
304
305 mctl->m_tname[IP_MASQ_TNAME_MAX-1] = 0;
306
307 mmod = ip_masq_mod_getbyname(mctl->m_tname);
308 if (mmod)
309 return mmod->mmod_ctl(optname, mctl, optlen);
310#ifdef CONFIG_KMOD
311 sprintf(kmod_name,"ip_masq_%s", mctl->m_tname);
312
313 IP_MASQ_DEBUG(1, "About to request \"%s\" module\n", kmod_name);
314
315
316
317
318 request_module(kmod_name);
319 mmod = ip_masq_mod_getbyname(mctl->m_tname);
320 if (mmod)
321 return mmod->mmod_ctl(optname, mctl, optlen);
322#endif
323 return ESRCH;
324}
325
