crypto/scompress.c

   1 // SPDX-License-Identifier: GPL-2.0-or-later
   2 /*
   3  * Synchronous Compression operations
   4  *
   5  * Copyright 2015 LG Electronics Inc.
   6  * Copyright (c) 2016, Intel Corporation
   7  * Author: Giovanni Cabiddu <giovanni.cabiddu@intel.com>
   8  */
   9
  10 #include <crypto/internal/acompress.h>
  11 #include <crypto/internal/scompress.h>
  12 #include <crypto/scatterwalk.h>
  13 #include <linux/cryptouser.h>
  14 #include <linux/err.h>
  15 #include <linux/kernel.h>
  16 #include <linux/module.h>
  17 #include <linux/scatterlist.h>
  18 #include <linux/seq_file.h>
  19 #include <linux/slab.h>
  20 #include <linux/string.h>
  21 #include <linux/vmalloc.h>
  22 #include <net/netlink.h>
  23
  24 #include "compress.h"
  25
  26 struct scomp_scratch {
  27         spinlock_t      lock;
  28         void            *src;
  29         void            *dst;
  30 };
  31
  32 static DEFINE_PER_CPU(struct scomp_scratch, scomp_scratch) = {
  33         .lock = __SPIN_LOCK_UNLOCKED(scomp_scratch.lock),
  34 };
  35
  36 static const struct crypto_type crypto_scomp_type;
  37 static int scomp_scratch_users;
  38 static DEFINE_MUTEX(scomp_lock);
  39
  40 static int __maybe_unused crypto_scomp_report(
  41         struct sk_buff *skb, struct crypto_alg *alg)
  42 {
  43         struct crypto_report_comp rscomp;
  44
  45         memset(&rscomp, 0, sizeof(rscomp));
  46
  47         strscpy(rscomp.type, "scomp", sizeof(rscomp.type));
  48
  49         return nla_put(skb, CRYPTOCFGA_REPORT_COMPRESS,
  50                        sizeof(rscomp), &rscomp);
  51 }
  52
  53 static void crypto_scomp_show(struct seq_file *m, struct crypto_alg *alg)
  54         __maybe_unused;
  55
  56 static void crypto_scomp_show(struct seq_file *m, struct crypto_alg *alg)
  57 {
  58         seq_puts(m, "type         : scomp\n");
  59 }
  60
  61 static void crypto_scomp_free_scratches(void)
  62 {
  63         struct scomp_scratch *scratch;
  64         int i;
  65
  66         for_each_possible_cpu(i) {
  67                 scratch = per_cpu_ptr(&scomp_scratch, i);
  68
  69                 vfree(scratch->src);
  70                 vfree(scratch->dst);
  71                 scratch->src = NULL;
  72                 scratch->dst = NULL;
  73         }
  74 }
  75
  76 static int crypto_scomp_alloc_scratches(void)
  77 {
  78         struct scomp_scratch *scratch;
  79         int i;
  80
  81         for_each_possible_cpu(i) {
  82                 void *mem;
  83
  84                 scratch = per_cpu_ptr(&scomp_scratch, i);
  85
  86                 mem = vmalloc_node(SCOMP_SCRATCH_SIZE, cpu_to_node(i));
  87                 if (!mem)
  88                         goto error;
  89                 scratch->src = mem;
  90                 mem = vmalloc_node(SCOMP_SCRATCH_SIZE, cpu_to_node(i));
  91                 if (!mem)
  92                         goto error;
  93                 scratch->dst = mem;
  94         }
  95         return 0;
  96 error:
  97         crypto_scomp_free_scratches();
  98         return -ENOMEM;
  99 }
 100
 101 static int crypto_scomp_init_tfm(struct crypto_tfm *tfm)
 102 {
 103         int ret = 0;
 104
 105         mutex_lock(&scomp_lock);
 106         if (!scomp_scratch_users++)
 107                 ret = crypto_scomp_alloc_scratches();
 108         mutex_unlock(&scomp_lock);
 109
 110         return ret;
 111 }
 112
 113 static int scomp_acomp_comp_decomp(struct acomp_req *req, int dir)
 114 {
 115         struct crypto_acomp *tfm = crypto_acomp_reqtfm(req);
 116         void **tfm_ctx = acomp_tfm_ctx(tfm);
 117         struct crypto_scomp *scomp = *tfm_ctx;
 118         void **ctx = acomp_request_ctx(req);
 119         struct scomp_scratch *scratch;
 120         unsigned int dlen;
 121         int ret;
 122
 123         if (!req->src || !req->slen || req->slen > SCOMP_SCRATCH_SIZE)
 124                 return -EINVAL;
 125
 126         if (req->dst && !req->dlen)
 127                 return -EINVAL;
 128
 129         if (!req->dlen || req->dlen > SCOMP_SCRATCH_SIZE)
 130                 req->dlen = SCOMP_SCRATCH_SIZE;
 131
 132         dlen = req->dlen;
 133
 134         scratch = raw_cpu_ptr(&scomp_scratch);
 135         spin_lock(&scratch->lock);
 136
 137         scatterwalk_map_and_copy(scratch->src, req->src, 0, req->slen, 0);
 138         if (dir)
 139                 ret = crypto_scomp_compress(scomp, scratch->src, req->slen,
 140                                             scratch->dst, &req->dlen, *ctx);
 141         else
 142                 ret = crypto_scomp_decompress(scomp, scratch->src, req->slen,
 143                                               scratch->dst, &req->dlen, *ctx);
 144         if (!ret) {
 145                 if (!req->dst) {
 146                         req->dst = sgl_alloc(req->dlen, GFP_ATOMIC, NULL);
 147                         if (!req->dst) {
 148                                 ret = -ENOMEM;
 149                                 goto out;
 150                         }
 151                 } else if (req->dlen > dlen) {
 152                         ret = -ENOSPC;
 153                         goto out;
 154                 }
 155                 scatterwalk_map_and_copy(scratch->dst, req->dst, 0, req->dlen,
 156                                          1);
 157         }
 158 out:
 159         spin_unlock(&scratch->lock);
 160         return ret;
 161 }
 162
 163 static int scomp_acomp_compress(struct acomp_req *req)
 164 {
 165         return scomp_acomp_comp_decomp(req, 1);
 166 }
 167
 168 static int scomp_acomp_decompress(struct acomp_req *req)
 169 {
 170         return scomp_acomp_comp_decomp(req, 0);
 171 }
 172
 173 static void crypto_exit_scomp_ops_async(struct crypto_tfm *tfm)
 174 {
 175         struct crypto_scomp **ctx = crypto_tfm_ctx(tfm);
 176
 177         crypto_free_scomp(*ctx);
 178
 179         mutex_lock(&scomp_lock);
 180         if (!--scomp_scratch_users)
 181                 crypto_scomp_free_scratches();
 182         mutex_unlock(&scomp_lock);
 183 }
 184
 185 int crypto_init_scomp_ops_async(struct crypto_tfm *tfm)
 186 {
 187         struct crypto_alg *calg = tfm->__crt_alg;
 188         struct crypto_acomp *crt = __crypto_acomp_tfm(tfm);
 189         struct crypto_scomp **ctx = crypto_tfm_ctx(tfm);
 190         struct crypto_scomp *scomp;
 191
 192         if (!crypto_mod_get(calg))
 193                 return -EAGAIN;
 194
 195         scomp = crypto_create_tfm(calg, &crypto_scomp_type);
 196         if (IS_ERR(scomp)) {
 197                 crypto_mod_put(calg);
 198                 return PTR_ERR(scomp);
 199         }
 200
 201         *ctx = scomp;
 202         tfm->exit = crypto_exit_scomp_ops_async;
 203
 204         crt->compress = scomp_acomp_compress;
 205         crt->decompress = scomp_acomp_decompress;
 206         crt->dst_free = sgl_free;
 207         crt->reqsize = sizeof(void *);
 208
 209         return 0;
 210 }
 211
 212 struct acomp_req *crypto_acomp_scomp_alloc_ctx(struct acomp_req *req)
 213 {
 214         struct crypto_acomp *acomp = crypto_acomp_reqtfm(req);
 215         struct crypto_tfm *tfm = crypto_acomp_tfm(acomp);
 216         struct crypto_scomp **tfm_ctx = crypto_tfm_ctx(tfm);
 217         struct crypto_scomp *scomp = *tfm_ctx;
 218         void *ctx;
 219
 220         ctx = crypto_scomp_alloc_ctx(scomp);
 221         if (IS_ERR(ctx)) {
 222                 kfree(req);
 223                 return NULL;
 224         }
 225
 226         *req->__ctx = ctx;
 227
 228         return req;
 229 }
 230
 231 void crypto_acomp_scomp_free_ctx(struct acomp_req *req)
 232 {
 233         struct crypto_acomp *acomp = crypto_acomp_reqtfm(req);
 234         struct crypto_tfm *tfm = crypto_acomp_tfm(acomp);
 235         struct crypto_scomp **tfm_ctx = crypto_tfm_ctx(tfm);
 236         struct crypto_scomp *scomp = *tfm_ctx;
 237         void *ctx = *req->__ctx;
 238
 239         if (ctx)
 240                 crypto_scomp_free_ctx(scomp, ctx);
 241 }
 242
 243 static const struct crypto_type crypto_scomp_type = {
 244         .extsize = crypto_alg_extsize,
 245         .init_tfm = crypto_scomp_init_tfm,
 246 #ifdef CONFIG_PROC_FS
 247         .show = crypto_scomp_show,
 248 #endif
 249 #if IS_ENABLED(CONFIG_CRYPTO_USER)
 250         .report = crypto_scomp_report,
 251 #endif
 252 #ifdef CONFIG_CRYPTO_STATS
 253         .report_stat = crypto_acomp_report_stat,
 254 #endif
 255         .maskclear = ~CRYPTO_ALG_TYPE_MASK,
 256         .maskset = CRYPTO_ALG_TYPE_MASK,
 257         .type = CRYPTO_ALG_TYPE_SCOMPRESS,
 258         .tfmsize = offsetof(struct crypto_scomp, base),
 259 };
 260
 261 int crypto_register_scomp(struct scomp_alg *alg)
 262 {
 263         struct crypto_alg *base = &alg->calg.base;
 264
 265         comp_prepare_alg(&alg->calg);
 266
 267         base->cra_type = &crypto_scomp_type;
 268         base->cra_flags |= CRYPTO_ALG_TYPE_SCOMPRESS;
 269
 270         return crypto_register_alg(base);
 271 }
 272 EXPORT_SYMBOL_GPL(crypto_register_scomp);
 273
 274 void crypto_unregister_scomp(struct scomp_alg *alg)
 275 {
 276         crypto_unregister_alg(&alg->base);
 277 }
 278 EXPORT_SYMBOL_GPL(crypto_unregister_scomp);
 279
 280 int crypto_register_scomps(struct scomp_alg *algs, int count)
 281 {
 282         int i, ret;
 283
 284         for (i = 0; i < count; i++) {
 285                 ret = crypto_register_scomp(&algs[i]);
 286                 if (ret)
 287                         goto err;
 288         }
 289
 290         return 0;
 291
 292 err:
 293         for (--i; i >= 0; --i)
 294                 crypto_unregister_scomp(&algs[i]);
 295
 296         return ret;
 297 }
 298 EXPORT_SYMBOL_GPL(crypto_register_scomps);
 299
 300 void crypto_unregister_scomps(struct scomp_alg *algs, int count)
 301 {
 302         int i;
 303
 304         for (i = count - 1; i >= 0; --i)
 305                 crypto_unregister_scomp(&algs[i]);
 306 }
 307 EXPORT_SYMBOL_GPL(crypto_unregister_scomps);
 308
 309 MODULE_LICENSE("GPL");
 310 MODULE_DESCRIPTION("Synchronous compression type");