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