1 // SPDX-License-Identifier: GPL-2.0-or-later 1 // SPDX-License-Identifier: GPL-2.0-or-later
2 /* 2 /*
3 * IP Payload Compression Protocol (IPComp) - 3 * IP Payload Compression Protocol (IPComp) - RFC3173.
4 * 4 *
5 * Copyright (c) 2003 James Morris <jmorris@in 5 * Copyright (c) 2003 James Morris <jmorris@intercode.com.au>
6 * Copyright (c) 2003-2008 Herbert Xu <herbert 6 * Copyright (c) 2003-2008 Herbert Xu <herbert@gondor.apana.org.au>
7 * 7 *
8 * Todo: 8 * Todo:
9 * - Tunable compression parameters. 9 * - Tunable compression parameters.
10 * - Compression stats. 10 * - Compression stats.
11 * - Adaptive compression. 11 * - Adaptive compression.
12 */ 12 */
13 13
14 #include <linux/crypto.h> 14 #include <linux/crypto.h>
15 #include <linux/err.h> 15 #include <linux/err.h>
16 #include <linux/list.h> 16 #include <linux/list.h>
17 #include <linux/module.h> 17 #include <linux/module.h>
18 #include <linux/mutex.h> 18 #include <linux/mutex.h>
19 #include <linux/percpu.h> 19 #include <linux/percpu.h>
20 #include <linux/slab.h> 20 #include <linux/slab.h>
21 #include <linux/smp.h> 21 #include <linux/smp.h>
22 #include <linux/vmalloc.h> 22 #include <linux/vmalloc.h>
23 #include <net/ip.h> 23 #include <net/ip.h>
24 #include <net/ipcomp.h> 24 #include <net/ipcomp.h>
25 #include <net/xfrm.h> 25 #include <net/xfrm.h>
26 26
27 struct ipcomp_tfms { 27 struct ipcomp_tfms {
28 struct list_head list; 28 struct list_head list;
29 struct crypto_comp * __percpu *tfms; 29 struct crypto_comp * __percpu *tfms;
30 int users; 30 int users;
31 }; 31 };
32 32
33 static DEFINE_MUTEX(ipcomp_resource_mutex); 33 static DEFINE_MUTEX(ipcomp_resource_mutex);
34 static void * __percpu *ipcomp_scratches; 34 static void * __percpu *ipcomp_scratches;
35 static int ipcomp_scratch_users; 35 static int ipcomp_scratch_users;
36 static LIST_HEAD(ipcomp_tfms_list); 36 static LIST_HEAD(ipcomp_tfms_list);
37 37
38 static int ipcomp_decompress(struct xfrm_state 38 static int ipcomp_decompress(struct xfrm_state *x, struct sk_buff *skb)
39 { 39 {
40 struct ipcomp_data *ipcd = x->data; 40 struct ipcomp_data *ipcd = x->data;
41 const int plen = skb->len; 41 const int plen = skb->len;
42 int dlen = IPCOMP_SCRATCH_SIZE; 42 int dlen = IPCOMP_SCRATCH_SIZE;
43 const u8 *start = skb->data; 43 const u8 *start = skb->data;
44 u8 *scratch = *this_cpu_ptr(ipcomp_scr 44 u8 *scratch = *this_cpu_ptr(ipcomp_scratches);
45 struct crypto_comp *tfm = *this_cpu_pt 45 struct crypto_comp *tfm = *this_cpu_ptr(ipcd->tfms);
46 int err = crypto_comp_decompress(tfm, 46 int err = crypto_comp_decompress(tfm, start, plen, scratch, &dlen);
47 int len; 47 int len;
48 48
49 if (err) 49 if (err)
50 return err; 50 return err;
51 51
52 if (dlen < (plen + sizeof(struct ip_co 52 if (dlen < (plen + sizeof(struct ip_comp_hdr)))
53 return -EINVAL; 53 return -EINVAL;
54 54
55 len = dlen - plen; 55 len = dlen - plen;
56 if (len > skb_tailroom(skb)) 56 if (len > skb_tailroom(skb))
57 len = skb_tailroom(skb); 57 len = skb_tailroom(skb);
58 58
59 __skb_put(skb, len); 59 __skb_put(skb, len);
60 60
61 len += plen; 61 len += plen;
62 skb_copy_to_linear_data(skb, scratch, 62 skb_copy_to_linear_data(skb, scratch, len);
63 63
64 while ((scratch += len, dlen -= len) > 64 while ((scratch += len, dlen -= len) > 0) {
65 skb_frag_t *frag; 65 skb_frag_t *frag;
66 struct page *page; 66 struct page *page;
67 67
68 if (WARN_ON(skb_shinfo(skb)->n 68 if (WARN_ON(skb_shinfo(skb)->nr_frags >= MAX_SKB_FRAGS))
69 return -EMSGSIZE; 69 return -EMSGSIZE;
70 70
71 frag = skb_shinfo(skb)->frags 71 frag = skb_shinfo(skb)->frags + skb_shinfo(skb)->nr_frags;
72 page = alloc_page(GFP_ATOMIC); 72 page = alloc_page(GFP_ATOMIC);
73 73
74 if (!page) 74 if (!page)
75 return -ENOMEM; 75 return -ENOMEM;
76 76
77 len = PAGE_SIZE; 77 len = PAGE_SIZE;
78 if (dlen < len) 78 if (dlen < len)
79 len = dlen; 79 len = dlen;
80 80
81 skb_frag_fill_page_desc(frag, 81 skb_frag_fill_page_desc(frag, page, 0, len);
82 memcpy(skb_frag_address(frag), 82 memcpy(skb_frag_address(frag), scratch, len);
83 83
84 skb->truesize += len; 84 skb->truesize += len;
85 skb->data_len += len; 85 skb->data_len += len;
86 skb->len += len; 86 skb->len += len;
87 87
88 skb_shinfo(skb)->nr_frags++; 88 skb_shinfo(skb)->nr_frags++;
89 } 89 }
90 90
91 return 0; 91 return 0;
92 } 92 }
93 93
94 int ipcomp_input(struct xfrm_state *x, struct 94 int ipcomp_input(struct xfrm_state *x, struct sk_buff *skb)
95 { 95 {
96 int nexthdr; 96 int nexthdr;
97 int err = -ENOMEM; 97 int err = -ENOMEM;
98 struct ip_comp_hdr *ipch; 98 struct ip_comp_hdr *ipch;
99 99
100 if (skb_linearize_cow(skb)) 100 if (skb_linearize_cow(skb))
101 goto out; 101 goto out;
102 102
103 skb->ip_summed = CHECKSUM_NONE; 103 skb->ip_summed = CHECKSUM_NONE;
104 104
105 /* Remove ipcomp header and decompress 105 /* Remove ipcomp header and decompress original payload */
106 ipch = (void *)skb->data; 106 ipch = (void *)skb->data;
107 nexthdr = ipch->nexthdr; 107 nexthdr = ipch->nexthdr;
108 108
109 skb->transport_header = skb->network_h 109 skb->transport_header = skb->network_header + sizeof(*ipch);
110 __skb_pull(skb, sizeof(*ipch)); 110 __skb_pull(skb, sizeof(*ipch));
111 err = ipcomp_decompress(x, skb); 111 err = ipcomp_decompress(x, skb);
112 if (err) 112 if (err)
113 goto out; 113 goto out;
114 114
115 err = nexthdr; 115 err = nexthdr;
116 116
117 out: 117 out:
118 return err; 118 return err;
119 } 119 }
120 EXPORT_SYMBOL_GPL(ipcomp_input); 120 EXPORT_SYMBOL_GPL(ipcomp_input);
121 121
122 static int ipcomp_compress(struct xfrm_state * 122 static int ipcomp_compress(struct xfrm_state *x, struct sk_buff *skb)
123 { 123 {
124 struct ipcomp_data *ipcd = x->data; 124 struct ipcomp_data *ipcd = x->data;
125 const int plen = skb->len; 125 const int plen = skb->len;
126 int dlen = IPCOMP_SCRATCH_SIZE; 126 int dlen = IPCOMP_SCRATCH_SIZE;
127 u8 *start = skb->data; 127 u8 *start = skb->data;
128 struct crypto_comp *tfm; 128 struct crypto_comp *tfm;
129 u8 *scratch; 129 u8 *scratch;
130 int err; 130 int err;
131 131
132 local_bh_disable(); 132 local_bh_disable();
133 scratch = *this_cpu_ptr(ipcomp_scratch 133 scratch = *this_cpu_ptr(ipcomp_scratches);
134 tfm = *this_cpu_ptr(ipcd->tfms); 134 tfm = *this_cpu_ptr(ipcd->tfms);
135 err = crypto_comp_compress(tfm, start, 135 err = crypto_comp_compress(tfm, start, plen, scratch, &dlen);
136 if (err) 136 if (err)
137 goto out; 137 goto out;
138 138
139 if ((dlen + sizeof(struct ip_comp_hdr) 139 if ((dlen + sizeof(struct ip_comp_hdr)) >= plen) {
140 err = -EMSGSIZE; 140 err = -EMSGSIZE;
141 goto out; 141 goto out;
142 } 142 }
143 143
144 memcpy(start + sizeof(struct ip_comp_h 144 memcpy(start + sizeof(struct ip_comp_hdr), scratch, dlen);
145 local_bh_enable(); 145 local_bh_enable();
146 146
147 pskb_trim(skb, dlen + sizeof(struct ip 147 pskb_trim(skb, dlen + sizeof(struct ip_comp_hdr));
148 return 0; 148 return 0;
149 149
150 out: 150 out:
151 local_bh_enable(); 151 local_bh_enable();
152 return err; 152 return err;
153 } 153 }
154 154
155 int ipcomp_output(struct xfrm_state *x, struct 155 int ipcomp_output(struct xfrm_state *x, struct sk_buff *skb)
156 { 156 {
157 int err; 157 int err;
158 struct ip_comp_hdr *ipch; 158 struct ip_comp_hdr *ipch;
159 struct ipcomp_data *ipcd = x->data; 159 struct ipcomp_data *ipcd = x->data;
160 160
161 if (skb->len < ipcd->threshold) { 161 if (skb->len < ipcd->threshold) {
162 /* Don't bother compressing */ 162 /* Don't bother compressing */
163 goto out_ok; 163 goto out_ok;
164 } 164 }
165 165
166 if (skb_linearize_cow(skb)) 166 if (skb_linearize_cow(skb))
167 goto out_ok; 167 goto out_ok;
168 168
169 err = ipcomp_compress(x, skb); 169 err = ipcomp_compress(x, skb);
170 170
171 if (err) { 171 if (err) {
172 goto out_ok; 172 goto out_ok;
173 } 173 }
174 174
175 /* Install ipcomp header, convert into 175 /* Install ipcomp header, convert into ipcomp datagram. */
176 ipch = ip_comp_hdr(skb); 176 ipch = ip_comp_hdr(skb);
177 ipch->nexthdr = *skb_mac_header(skb); 177 ipch->nexthdr = *skb_mac_header(skb);
178 ipch->flags = 0; 178 ipch->flags = 0;
179 ipch->cpi = htons((u16 )ntohl(x->id.sp 179 ipch->cpi = htons((u16 )ntohl(x->id.spi));
180 *skb_mac_header(skb) = IPPROTO_COMP; 180 *skb_mac_header(skb) = IPPROTO_COMP;
181 out_ok: 181 out_ok:
182 skb_push(skb, -skb_network_offset(skb) 182 skb_push(skb, -skb_network_offset(skb));
183 return 0; 183 return 0;
184 } 184 }
185 EXPORT_SYMBOL_GPL(ipcomp_output); 185 EXPORT_SYMBOL_GPL(ipcomp_output);
186 186
187 static void ipcomp_free_scratches(void) 187 static void ipcomp_free_scratches(void)
188 { 188 {
189 int i; 189 int i;
190 void * __percpu *scratches; 190 void * __percpu *scratches;
191 191
192 if (--ipcomp_scratch_users) 192 if (--ipcomp_scratch_users)
193 return; 193 return;
194 194
195 scratches = ipcomp_scratches; 195 scratches = ipcomp_scratches;
196 if (!scratches) 196 if (!scratches)
197 return; 197 return;
198 198
199 for_each_possible_cpu(i) 199 for_each_possible_cpu(i)
200 vfree(*per_cpu_ptr(scratches, 200 vfree(*per_cpu_ptr(scratches, i));
201 201
202 free_percpu(scratches); 202 free_percpu(scratches);
203 ipcomp_scratches = NULL; 203 ipcomp_scratches = NULL;
204 } 204 }
205 205
206 static void * __percpu *ipcomp_alloc_scratches 206 static void * __percpu *ipcomp_alloc_scratches(void)
207 { 207 {
208 void * __percpu *scratches; 208 void * __percpu *scratches;
209 int i; 209 int i;
210 210
211 if (ipcomp_scratch_users++) 211 if (ipcomp_scratch_users++)
212 return ipcomp_scratches; 212 return ipcomp_scratches;
213 213
214 scratches = alloc_percpu(void *); 214 scratches = alloc_percpu(void *);
215 if (!scratches) 215 if (!scratches)
216 return NULL; 216 return NULL;
217 217
218 ipcomp_scratches = scratches; 218 ipcomp_scratches = scratches;
219 219
220 for_each_possible_cpu(i) { 220 for_each_possible_cpu(i) {
221 void *scratch; 221 void *scratch;
222 222
223 scratch = vmalloc_node(IPCOMP_ 223 scratch = vmalloc_node(IPCOMP_SCRATCH_SIZE, cpu_to_node(i));
224 if (!scratch) 224 if (!scratch)
225 return NULL; 225 return NULL;
226 *per_cpu_ptr(scratches, i) = s 226 *per_cpu_ptr(scratches, i) = scratch;
227 } 227 }
228 228
229 return scratches; 229 return scratches;
230 } 230 }
231 231
232 static void ipcomp_free_tfms(struct crypto_com 232 static void ipcomp_free_tfms(struct crypto_comp * __percpu *tfms)
233 { 233 {
234 struct ipcomp_tfms *pos; 234 struct ipcomp_tfms *pos;
235 int cpu; 235 int cpu;
236 236
237 list_for_each_entry(pos, &ipcomp_tfms_ 237 list_for_each_entry(pos, &ipcomp_tfms_list, list) {
238 if (pos->tfms == tfms) 238 if (pos->tfms == tfms)
239 break; 239 break;
240 } 240 }
241 241
242 WARN_ON(list_entry_is_head(pos, &ipcom 242 WARN_ON(list_entry_is_head(pos, &ipcomp_tfms_list, list));
243 243
244 if (--pos->users) 244 if (--pos->users)
245 return; 245 return;
246 246
247 list_del(&pos->list); 247 list_del(&pos->list);
248 kfree(pos); 248 kfree(pos);
249 249
250 if (!tfms) 250 if (!tfms)
251 return; 251 return;
252 252
253 for_each_possible_cpu(cpu) { 253 for_each_possible_cpu(cpu) {
254 struct crypto_comp *tfm = *per 254 struct crypto_comp *tfm = *per_cpu_ptr(tfms, cpu);
255 crypto_free_comp(tfm); 255 crypto_free_comp(tfm);
256 } 256 }
257 free_percpu(tfms); 257 free_percpu(tfms);
258 } 258 }
259 259
260 static struct crypto_comp * __percpu *ipcomp_a 260 static struct crypto_comp * __percpu *ipcomp_alloc_tfms(const char *alg_name)
261 { 261 {
262 struct ipcomp_tfms *pos; 262 struct ipcomp_tfms *pos;
263 struct crypto_comp * __percpu *tfms; 263 struct crypto_comp * __percpu *tfms;
264 int cpu; 264 int cpu;
265 265
266 266
267 list_for_each_entry(pos, &ipcomp_tfms_ 267 list_for_each_entry(pos, &ipcomp_tfms_list, list) {
268 struct crypto_comp *tfm; 268 struct crypto_comp *tfm;
269 269
270 /* This can be any valid CPU I 270 /* This can be any valid CPU ID so we don't need locking. */
271 tfm = this_cpu_read(*pos->tfms 271 tfm = this_cpu_read(*pos->tfms);
272 272
273 if (!strcmp(crypto_comp_name(t 273 if (!strcmp(crypto_comp_name(tfm), alg_name)) {
274 pos->users++; 274 pos->users++;
275 return pos->tfms; 275 return pos->tfms;
276 } 276 }
277 } 277 }
278 278
279 pos = kmalloc(sizeof(*pos), GFP_KERNEL 279 pos = kmalloc(sizeof(*pos), GFP_KERNEL);
280 if (!pos) 280 if (!pos)
281 return NULL; 281 return NULL;
282 282
283 pos->users = 1; 283 pos->users = 1;
284 INIT_LIST_HEAD(&pos->list); 284 INIT_LIST_HEAD(&pos->list);
285 list_add(&pos->list, &ipcomp_tfms_list 285 list_add(&pos->list, &ipcomp_tfms_list);
286 286
287 pos->tfms = tfms = alloc_percpu(struct 287 pos->tfms = tfms = alloc_percpu(struct crypto_comp *);
288 if (!tfms) 288 if (!tfms)
289 goto error; 289 goto error;
290 290
291 for_each_possible_cpu(cpu) { 291 for_each_possible_cpu(cpu) {
292 struct crypto_comp *tfm = cryp 292 struct crypto_comp *tfm = crypto_alloc_comp(alg_name, 0,
293 293 CRYPTO_ALG_ASYNC);
294 if (IS_ERR(tfm)) 294 if (IS_ERR(tfm))
295 goto error; 295 goto error;
296 *per_cpu_ptr(tfms, cpu) = tfm; 296 *per_cpu_ptr(tfms, cpu) = tfm;
297 } 297 }
298 298
299 return tfms; 299 return tfms;
300 300
301 error: 301 error:
302 ipcomp_free_tfms(tfms); 302 ipcomp_free_tfms(tfms);
303 return NULL; 303 return NULL;
304 } 304 }
305 305
306 static void ipcomp_free_data(struct ipcomp_dat 306 static void ipcomp_free_data(struct ipcomp_data *ipcd)
307 { 307 {
308 if (ipcd->tfms) 308 if (ipcd->tfms)
309 ipcomp_free_tfms(ipcd->tfms); 309 ipcomp_free_tfms(ipcd->tfms);
310 ipcomp_free_scratches(); 310 ipcomp_free_scratches();
311 } 311 }
312 312
313 void ipcomp_destroy(struct xfrm_state *x) 313 void ipcomp_destroy(struct xfrm_state *x)
314 { 314 {
315 struct ipcomp_data *ipcd = x->data; 315 struct ipcomp_data *ipcd = x->data;
316 if (!ipcd) 316 if (!ipcd)
317 return; 317 return;
318 xfrm_state_delete_tunnel(x); 318 xfrm_state_delete_tunnel(x);
319 mutex_lock(&ipcomp_resource_mutex); 319 mutex_lock(&ipcomp_resource_mutex);
320 ipcomp_free_data(ipcd); 320 ipcomp_free_data(ipcd);
321 mutex_unlock(&ipcomp_resource_mutex); 321 mutex_unlock(&ipcomp_resource_mutex);
322 kfree(ipcd); 322 kfree(ipcd);
323 } 323 }
324 EXPORT_SYMBOL_GPL(ipcomp_destroy); 324 EXPORT_SYMBOL_GPL(ipcomp_destroy);
325 325
326 int ipcomp_init_state(struct xfrm_state *x, st 326 int ipcomp_init_state(struct xfrm_state *x, struct netlink_ext_ack *extack)
327 { 327 {
328 int err; 328 int err;
329 struct ipcomp_data *ipcd; 329 struct ipcomp_data *ipcd;
330 struct xfrm_algo_desc *calg_desc; 330 struct xfrm_algo_desc *calg_desc;
331 331
332 err = -EINVAL; 332 err = -EINVAL;
333 if (!x->calg) { 333 if (!x->calg) {
334 NL_SET_ERR_MSG(extack, "Missin 334 NL_SET_ERR_MSG(extack, "Missing required compression algorithm");
335 goto out; 335 goto out;
336 } 336 }
337 337
338 if (x->encap) { 338 if (x->encap) {
339 NL_SET_ERR_MSG(extack, "IPComp 339 NL_SET_ERR_MSG(extack, "IPComp is not compatible with encapsulation");
340 goto out; 340 goto out;
341 } 341 }
342 342
343 err = -ENOMEM; 343 err = -ENOMEM;
344 ipcd = kzalloc(sizeof(*ipcd), GFP_KERN 344 ipcd = kzalloc(sizeof(*ipcd), GFP_KERNEL);
345 if (!ipcd) 345 if (!ipcd)
346 goto out; 346 goto out;
347 347
348 mutex_lock(&ipcomp_resource_mutex); 348 mutex_lock(&ipcomp_resource_mutex);
349 if (!ipcomp_alloc_scratches()) 349 if (!ipcomp_alloc_scratches())
350 goto error; 350 goto error;
351 351
352 ipcd->tfms = ipcomp_alloc_tfms(x->calg 352 ipcd->tfms = ipcomp_alloc_tfms(x->calg->alg_name);
353 if (!ipcd->tfms) 353 if (!ipcd->tfms)
354 goto error; 354 goto error;
355 mutex_unlock(&ipcomp_resource_mutex); 355 mutex_unlock(&ipcomp_resource_mutex);
356 356
357 calg_desc = xfrm_calg_get_byname(x->ca 357 calg_desc = xfrm_calg_get_byname(x->calg->alg_name, 0);
358 BUG_ON(!calg_desc); 358 BUG_ON(!calg_desc);
359 ipcd->threshold = calg_desc->uinfo.com 359 ipcd->threshold = calg_desc->uinfo.comp.threshold;
360 x->data = ipcd; 360 x->data = ipcd;
361 err = 0; 361 err = 0;
362 out: 362 out:
363 return err; 363 return err;
364 364
365 error: 365 error:
366 ipcomp_free_data(ipcd); 366 ipcomp_free_data(ipcd);
367 mutex_unlock(&ipcomp_resource_mutex); 367 mutex_unlock(&ipcomp_resource_mutex);
368 kfree(ipcd); 368 kfree(ipcd);
369 goto out; 369 goto out;
370 } 370 }
371 EXPORT_SYMBOL_GPL(ipcomp_init_state); 371 EXPORT_SYMBOL_GPL(ipcomp_init_state);
372 372
373 MODULE_LICENSE("GPL"); 373 MODULE_LICENSE("GPL");
374 MODULE_DESCRIPTION("IP Payload Compression Pro 374 MODULE_DESCRIPTION("IP Payload Compression Protocol (IPComp) - RFC3173");
375 MODULE_AUTHOR("James Morris <jmorris@intercode 375 MODULE_AUTHOR("James Morris <jmorris@intercode.com.au>");
376 376
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