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         int ret;
 128
 129         if (!req->src || !req->slen || req->slen > SCOMP_SCRATCH_SIZE)
 130                 return -EINVAL;
 131
 132         if (req->dst && !req->dlen)
 133                 return -EINVAL;
 134
 135         if (!req->dlen || req->dlen > SCOMP_SCRATCH_SIZE)
 136                 req->dlen = SCOMP_SCRATCH_SIZE;
 137
 138         scratch = raw_cpu_ptr(&scomp_scratch);
 139         spin_lock(&scratch->lock);
 140
 141         scatterwalk_map_and_copy(scratch->src, req->src, 0, req->slen, 0);
 142         if (dir)
 143                 ret = crypto_scomp_compress(scomp, scratch->src, req->slen,
 144                                             scratch->dst, &req->dlen, *ctx);
 145         else
 146                 ret = crypto_scomp_decompress(scomp, scratch->src, req->slen,
 147                                               scratch->dst, &req->dlen, *ctx);
 148         if (!ret) {
 149                 if (!req->dst) {
 150                         req->dst = sgl_alloc(req->dlen, GFP_ATOMIC, NULL);
 151                         if (!req->dst) {
 152                                 ret = -ENOMEM;
 153                                 goto out;
 154                         }
 155                 }
 156                 scatterwalk_map_and_copy(scratch->dst, req->dst, 0, req->dlen,
 157                                          1);
 158         }
 159 out:
 160         spin_unlock(&scratch->lock);
 161         return ret;
 162 }
 163
 164 static int scomp_acomp_compress(struct acomp_req *req)
 165 {
 166         return scomp_acomp_comp_decomp(req, 1);
 167 }
 168
 169 static int scomp_acomp_decompress(struct acomp_req *req)
 170 {
 171         return scomp_acomp_comp_decomp(req, 0);
 172 }
 173
 174 static void crypto_exit_scomp_ops_async(struct crypto_tfm *tfm)
 175 {
 176         struct crypto_scomp **ctx = crypto_tfm_ctx(tfm);
 177
 178         crypto_free_scomp(*ctx);
 179
 180         mutex_lock(&scomp_lock);
 181         if (!--scomp_scratch_users)
 182                 crypto_scomp_free_scratches();
 183         mutex_unlock(&scomp_lock);
 184 }
 185
 186 int crypto_init_scomp_ops_async(struct crypto_tfm *tfm)
 187 {
 188         struct crypto_alg *calg = tfm->__crt_alg;
 189         struct crypto_acomp *crt = __crypto_acomp_tfm(tfm);
 190         struct crypto_scomp **ctx = crypto_tfm_ctx(tfm);
 191         struct crypto_scomp *scomp;
 192
 193         if (!crypto_mod_get(calg))
 194                 return -EAGAIN;
 195
 196         scomp = crypto_create_tfm(calg, &crypto_scomp_type);
 197         if (IS_ERR(scomp)) {
 198                 crypto_mod_put(calg);
 199                 return PTR_ERR(scomp);
 200         }
 201
 202         *ctx = scomp;
 203         tfm->exit = crypto_exit_scomp_ops_async;
 204
 205         crt->compress = scomp_acomp_compress;
 206         crt->decompress = scomp_acomp_decompress;
 207         crt->dst_free = sgl_free;
 208         crt->reqsize = sizeof(void *);
 209
 210         return 0;
 211 }
 212
 213 struct acomp_req *crypto_acomp_scomp_alloc_ctx(struct acomp_req *req)
 214 {
 215         struct crypto_acomp *acomp = crypto_acomp_reqtfm(req);
 216         struct crypto_tfm *tfm = crypto_acomp_tfm(acomp);
 217         struct crypto_scomp **tfm_ctx = crypto_tfm_ctx(tfm);
 218         struct crypto_scomp *scomp = *tfm_ctx;
 219         void *ctx;
 220
 221         ctx = crypto_scomp_alloc_ctx(scomp);
 222         if (IS_ERR(ctx)) {
 223                 kfree(req);
 224                 return NULL;
 225         }
 226
 227         *req->__ctx = ctx;
 228
 229         return req;
 230 }
 231
 232 void crypto_acomp_scomp_free_ctx(struct acomp_req *req)
 233 {
 234         struct crypto_acomp *acomp = crypto_acomp_reqtfm(req);
 235         struct crypto_tfm *tfm = crypto_acomp_tfm(acomp);
 236         struct crypto_scomp **tfm_ctx = crypto_tfm_ctx(tfm);
 237         struct crypto_scomp *scomp = *tfm_ctx;
 238         void *ctx = *req->__ctx;
 239
 240         if (ctx)
 241                 crypto_scomp_free_ctx(scomp, ctx);
 242 }
 243
 244 static const struct crypto_type crypto_scomp_type = {
 245         .extsize = crypto_alg_extsize,
 246         .init_tfm = crypto_scomp_init_tfm,
 247 #ifdef CONFIG_PROC_FS
 248         .show = crypto_scomp_show,
 249 #endif
 250         .report = crypto_scomp_report,
 251         .maskclear = ~CRYPTO_ALG_TYPE_MASK,
 252         .maskset = CRYPTO_ALG_TYPE_MASK,
 253         .type = CRYPTO_ALG_TYPE_SCOMPRESS,
 254         .tfmsize = offsetof(struct crypto_scomp, base),
 255 };
 256
 257 int crypto_register_scomp(struct scomp_alg *alg)
 258 {
 259         struct crypto_alg *base = &alg->base;
 260
 261         base->cra_type = &crypto_scomp_type;
 262         base->cra_flags &= ~CRYPTO_ALG_TYPE_MASK;
 263         base->cra_flags |= CRYPTO_ALG_TYPE_SCOMPRESS;
 264
 265         return crypto_register_alg(base);
 266 }
 267 EXPORT_SYMBOL_GPL(crypto_register_scomp);
 268
 269 int crypto_unregister_scomp(struct scomp_alg *alg)
 270 {
 271         return crypto_unregister_alg(&alg->base);
 272 }
 273 EXPORT_SYMBOL_GPL(crypto_unregister_scomp);
 274
 275 int crypto_register_scomps(struct scomp_alg *algs, int count)
 276 {
 277         int i, ret;
 278
 279         for (i = 0; i < count; i++) {
 280                 ret = crypto_register_scomp(&algs[i]);
 281                 if (ret)
 282                         goto err;
 283         }
 284
 285         return 0;
 286
 287 err:
 288         for (--i; i >= 0; --i)
 289                 crypto_unregister_scomp(&algs[i]);
 290
 291         return ret;
 292 }
 293 EXPORT_SYMBOL_GPL(crypto_register_scomps);
 294
 295 void crypto_unregister_scomps(struct scomp_alg *algs, int count)
 296 {
 297         int i;
 298
 299         for (i = count - 1; i >= 0; --i)
 300                 crypto_unregister_scomp(&algs[i]);
 301 }
 302 EXPORT_SYMBOL_GPL(crypto_unregister_scomps);
 303
 304 MODULE_LICENSE("GPL");
 305 MODULE_DESCRIPTION("Synchronous compression type");