1 /*
2 * Synchronous Compression operations
3 *
4 * Copyright 2015 LG Electronics Inc.
5 * Copyright (c) 2016, Intel Corporation
6 * Author: Giovanni Cabiddu <giovanni.cabiddu@intel.com>
7 *
8 * This program is free software; you can redistribute it and/or modify it
9 * under the terms of the GNU General Public License as published by the Free
10 * Software Foundation; either version 2 of the License, or (at your option)
11 * any later version.
12 *
13 */
14 #include <linux/errno.h>
15 #include <linux/kernel.h>
16 #include <linux/module.h>
17 #include <linux/seq_file.h>
18 #include <linux/slab.h>
19 #include <linux/string.h>
20 #include <linux/crypto.h>
21 #include <linux/compiler.h>
22 #include <linux/vmalloc.h>
23 #include <crypto/algapi.h>
24 #include <linux/cryptouser.h>
25 #include <net/netlink.h>
26 #include <linux/scatterlist.h>
27 #include <crypto/scatterwalk.h>
28 #include <crypto/internal/acompress.h>
29 #include <crypto/internal/scompress.h>
30 #include "internal.h"
31
32 static const struct crypto_type crypto_scomp_type;
33 static void * __percpu *scomp_src_scratches;
34 static void * __percpu *scomp_dst_scratches;
35 static int scomp_scratch_users;
36 static DEFINE_MUTEX(scomp_lock);
37
38 #ifdef CONFIG_NET
39 static int crypto_scomp_report(struct sk_buff *skb, struct crypto_alg *alg)
40 {
41 struct crypto_report_comp rscomp;
42
43 strncpy(rscomp.type, "scomp", sizeof(rscomp.type));
44
45 if (nla_put(skb, CRYPTOCFGA_REPORT_COMPRESS,
46 sizeof(struct crypto_report_comp), &rscomp))
47 goto nla_put_failure;
48 return 0;
49
50 nla_put_failure:
51 return -EMSGSIZE;
52 }
53 #else
54 static int crypto_scomp_report(struct sk_buff *skb, struct crypto_alg *alg)
55 {
56 return -ENOSYS;
57 }
58 #endif
59
60 static void crypto_scomp_show(struct seq_file *m, struct crypto_alg *alg)
61 __maybe_unused;
62
63 static void crypto_scomp_show(struct seq_file *m, struct crypto_alg *alg)
64 {
65 seq_puts(m, "type : scomp\n");
66 }
67
68 static int crypto_scomp_init_tfm(struct crypto_tfm *tfm)
69 {
70 return 0;
71 }
72
73 static void crypto_scomp_free_scratches(void * __percpu *scratches)
74 {
75 int i;
76
77 if (!scratches)
78 return;
79
80 for_each_possible_cpu(i)
81 vfree(*per_cpu_ptr(scratches, i));
82
83 free_percpu(scratches);
84 }
85
86 static void * __percpu *crypto_scomp_alloc_scratches(void)
87 {
88 void * __percpu *scratches;
89 int i;
90
91 scratches = alloc_percpu(void *);
92 if (!scratches)
93 return NULL;
94
95 for_each_possible_cpu(i) {
96 void *scratch;
97
98 scratch = vmalloc_node(SCOMP_SCRATCH_SIZE, cpu_to_node(i));
99 if (!scratch)
100 goto error;
101 *per_cpu_ptr(scratches, i) = scratch;
102 }
103
104 return scratches;
105
106 error:
107 crypto_scomp_free_scratches(scratches);
108 return NULL;
109 }
110
111 static void crypto_scomp_free_all_scratches(void)
112 {
113 if (!--scomp_scratch_users) {
114 crypto_scomp_free_scratches(scomp_src_scratches);
115 crypto_scomp_free_scratches(scomp_dst_scratches);
116 scomp_src_scratches = NULL;
117 scomp_dst_scratches = NULL;
118 }
119 }
120
121 static int crypto_scomp_alloc_all_scratches(void)
122 {
123 if (!scomp_scratch_users++) {
124 scomp_src_scratches = crypto_scomp_alloc_scratches();
125 if (!scomp_src_scratches)
126 return -ENOMEM;
127 scomp_dst_scratches = crypto_scomp_alloc_scratches();
128 if (!scomp_dst_scratches)
129 return -ENOMEM;
130 }
131 return 0;
132 }
133
134 static void crypto_scomp_sg_free(struct scatterlist *sgl)
135 {
136 int i, n;
137 struct page *page;
138
139 if (!sgl)
140 return;
141
142 n = sg_nents(sgl);
143 for_each_sg(sgl, sgl, n, i) {
144 page = sg_page(sgl);
145 if (page)
146 __free_page(page);
147 }
148
149 kfree(sgl);
150 }
151
152 static struct scatterlist *crypto_scomp_sg_alloc(size_t size, gfp_t gfp)
153 {
154 struct scatterlist *sgl;
155 struct page *page;
156 int i, n;
157
158 n = ((size - 1) >> PAGE_SHIFT) + 1;
159
160 sgl = kmalloc_array(n, sizeof(struct scatterlist), gfp);
161 if (!sgl)
162 return NULL;
163
164 sg_init_table(sgl, n);
165
166 for (i = 0; i < n; i++) {
167 page = alloc_page(gfp);
168 if (!page)
169 goto err;
170 sg_set_page(sgl + i, page, PAGE_SIZE, 0);
171 }
172
173 return sgl;
174
175 err:
176 sg_mark_end(sgl + i);
177 crypto_scomp_sg_free(sgl);
178 return NULL;
179 }
180
181 static int scomp_acomp_comp_decomp(struct acomp_req *req, int dir)
182 {
183 struct crypto_acomp *tfm = crypto_acomp_reqtfm(req);
184 void **tfm_ctx = acomp_tfm_ctx(tfm);
185 struct crypto_scomp *scomp = *tfm_ctx;
186 void **ctx = acomp_request_ctx(req);
187 const int cpu = get_cpu();
188 u8 *scratch_src = *per_cpu_ptr(scomp_src_scratches, cpu);
189 u8 *scratch_dst = *per_cpu_ptr(scomp_dst_scratches, cpu);
190 int ret;
191
192 if (!req->src || !req->slen || req->slen > SCOMP_SCRATCH_SIZE) {
193 ret = -EINVAL;
194 goto out;
195 }
196
197 if (req->dst && !req->dlen) {
198 ret = -EINVAL;
199 goto out;
200 }
201
202 if (!req->dlen || req->dlen > SCOMP_SCRATCH_SIZE)
203 req->dlen = SCOMP_SCRATCH_SIZE;
204
205 scatterwalk_map_and_copy(scratch_src, req->src, 0, req->slen, 0);
206 if (dir)
207 ret = crypto_scomp_compress(scomp, scratch_src, req->slen,
208 scratch_dst, &req->dlen, *ctx);
209 else
210 ret = crypto_scomp_decompress(scomp, scratch_src, req->slen,
211 scratch_dst, &req->dlen, *ctx);
212 if (!ret) {
213 if (!req->dst) {
214 req->dst = crypto_scomp_sg_alloc(req->dlen, GFP_ATOMIC);
215 if (!req->dst)
216 goto out;
217 }
218 scatterwalk_map_and_copy(scratch_dst, req->dst, 0, req->dlen,
219 1);
220 }
221 out:
222 put_cpu();
223 return ret;
224 }
225
226 static int scomp_acomp_compress(struct acomp_req *req)
227 {
228 return scomp_acomp_comp_decomp(req, 1);
229 }
230
231 static int scomp_acomp_decompress(struct acomp_req *req)
232 {
233 return scomp_acomp_comp_decomp(req, 0);
234 }
235
236 static void crypto_exit_scomp_ops_async(struct crypto_tfm *tfm)
237 {
238 struct crypto_scomp **ctx = crypto_tfm_ctx(tfm);
239
240 crypto_free_scomp(*ctx);
241 }
242
243 int crypto_init_scomp_ops_async(struct crypto_tfm *tfm)
244 {
245 struct crypto_alg *calg = tfm->__crt_alg;
246 struct crypto_acomp *crt = __crypto_acomp_tfm(tfm);
247 struct crypto_scomp **ctx = crypto_tfm_ctx(tfm);
248 struct crypto_scomp *scomp;
249
250 if (!crypto_mod_get(calg))
251 return -EAGAIN;
252
253 scomp = crypto_create_tfm(calg, &crypto_scomp_type);
254 if (IS_ERR(scomp)) {
255 crypto_mod_put(calg);
256 return PTR_ERR(scomp);
257 }
258
259 *ctx = scomp;
260 tfm->exit = crypto_exit_scomp_ops_async;
261
262 crt->compress = scomp_acomp_compress;
263 crt->decompress = scomp_acomp_decompress;
264 crt->dst_free = crypto_scomp_sg_free;
265 crt->reqsize = sizeof(void *);
266
267 return 0;
268 }
269
270 struct acomp_req *crypto_acomp_scomp_alloc_ctx(struct acomp_req *req)
271 {
272 struct crypto_acomp *acomp = crypto_acomp_reqtfm(req);
273 struct crypto_tfm *tfm = crypto_acomp_tfm(acomp);
274 struct crypto_scomp **tfm_ctx = crypto_tfm_ctx(tfm);
275 struct crypto_scomp *scomp = *tfm_ctx;
276 void *ctx;
277
278 ctx = crypto_scomp_alloc_ctx(scomp);
279 if (IS_ERR(ctx)) {
280 kfree(req);
281 return NULL;
282 }
283
284 *req->__ctx = ctx;
285
286 return req;
287 }
288
289 void crypto_acomp_scomp_free_ctx(struct acomp_req *req)
290 {
291 struct crypto_acomp *acomp = crypto_acomp_reqtfm(req);
292 struct crypto_tfm *tfm = crypto_acomp_tfm(acomp);
293 struct crypto_scomp **tfm_ctx = crypto_tfm_ctx(tfm);
294 struct crypto_scomp *scomp = *tfm_ctx;
295 void *ctx = *req->__ctx;
296
297 if (ctx)
298 crypto_scomp_free_ctx(scomp, ctx);
299 }
300
301 static const struct crypto_type crypto_scomp_type = {
302 .extsize = crypto_alg_extsize,
303 .init_tfm = crypto_scomp_init_tfm,
304 #ifdef CONFIG_PROC_FS
305 .show = crypto_scomp_show,
306 #endif
307 .report = crypto_scomp_report,
308 .maskclear = ~CRYPTO_ALG_TYPE_MASK,
309 .maskset = CRYPTO_ALG_TYPE_MASK,
310 .type = CRYPTO_ALG_TYPE_SCOMPRESS,
311 .tfmsize = offsetof(struct crypto_scomp, base),
312 };
313
314 int crypto_register_scomp(struct scomp_alg *alg)
315 {
316 struct crypto_alg *base = &alg->base;
317 int ret = -ENOMEM;
318
319 mutex_lock(&scomp_lock);
320 if (crypto_scomp_alloc_all_scratches())
321 goto error;
322
323 base->cra_type = &crypto_scomp_type;
324 base->cra_flags &= ~CRYPTO_ALG_TYPE_MASK;
325 base->cra_flags |= CRYPTO_ALG_TYPE_SCOMPRESS;
326
327 ret = crypto_register_alg(base);
328 if (ret)
329 goto error;
330
331 mutex_unlock(&scomp_lock);
332 return ret;
333
334 error:
335 crypto_scomp_free_all_scratches();
336 mutex_unlock(&scomp_lock);
337 return ret;
338 }
339 EXPORT_SYMBOL_GPL(crypto_register_scomp);
340
341 int crypto_unregister_scomp(struct scomp_alg *alg)
342 {
343 int ret;
344
345 mutex_lock(&scomp_lock);
346 ret = crypto_unregister_alg(&alg->base);
347 crypto_scomp_free_all_scratches();
348 mutex_unlock(&scomp_lock);
349
350 return ret;
351 }
352 EXPORT_SYMBOL_GPL(crypto_unregister_scomp);
353
354 int crypto_register_scomps(struct scomp_alg *algs, int count)
355 {
356 int i, ret;
357
358 for (i = 0; i < count; i++) {
359 ret = crypto_register_scomp(&algs[i]);
360 if (ret)
361 goto err;
362 }
363
364 return 0;
365
366 err:
367 for (--i; i >= 0; --i)
368 crypto_unregister_scomp(&algs[i]);
369
370 return ret;
371 }
372 EXPORT_SYMBOL_GPL(crypto_register_scomps);
373
374 void crypto_unregister_scomps(struct scomp_alg *algs, int count)
375 {
376 int i;
377
378 for (i = count - 1; i >= 0; --i)
379 crypto_unregister_scomp(&algs[i]);
380 }
381 EXPORT_SYMBOL_GPL(crypto_unregister_scomps);
382
383 MODULE_LICENSE("GPL");
384 MODULE_DESCRIPTION("Synchronous compression type");
385
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