crypto/akcipher.c

   1 // SPDX-License-Identifier: GPL-2.0-or-later
   2 /*
   3  * Public Key Encryption
   4  *
   5  * Copyright (c) 2015, Intel Corporation
   6  * Authors: Tadeusz Struk <tadeusz.struk@intel.com>
   7  */
   8 #include <crypto/internal/akcipher.h>
   9 #include <linux/cryptouser.h>
  10 #include <linux/errno.h>
  11 #include <linux/kernel.h>
  12 #include <linux/module.h>
  13 #include <linux/scatterlist.h>
  14 #include <linux/seq_file.h>
  15 #include <linux/slab.h>
  16 #include <linux/string.h>
  17 #include <net/netlink.h>
  18
  19 #include "internal.h"
  20
  21 #define CRYPTO_ALG_TYPE_AHASH_MASK      0x0000000e
  22
  23 static int __maybe_unused crypto_akcipher_report(
  24         struct sk_buff *skb, struct crypto_alg *alg)
  25 {
  26         struct crypto_report_akcipher rakcipher;
  27
  28         memset(&rakcipher, 0, sizeof(rakcipher));
  29
  30         strscpy(rakcipher.type, "akcipher", sizeof(rakcipher.type));
  31
  32         return nla_put(skb, CRYPTOCFGA_REPORT_AKCIPHER,
  33                        sizeof(rakcipher), &rakcipher);
  34 }
  35
  36 static void crypto_akcipher_show(struct seq_file *m, struct crypto_alg *alg)
  37         __maybe_unused;
  38
  39 static void crypto_akcipher_show(struct seq_file *m, struct crypto_alg *alg)
  40 {
  41         seq_puts(m, "type         : akcipher\n");
  42 }
  43
  44 static void crypto_akcipher_exit_tfm(struct crypto_tfm *tfm)
  45 {
  46         struct crypto_akcipher *akcipher = __crypto_akcipher_tfm(tfm);
  47         struct akcipher_alg *alg = crypto_akcipher_alg(akcipher);
  48
  49         alg->exit(akcipher);
  50 }
  51
  52 static int crypto_akcipher_init_tfm(struct crypto_tfm *tfm)
  53 {
  54         struct crypto_akcipher *akcipher = __crypto_akcipher_tfm(tfm);
  55         struct akcipher_alg *alg = crypto_akcipher_alg(akcipher);
  56
  57         if (alg->exit)
  58                 akcipher->base.exit = crypto_akcipher_exit_tfm;
  59
  60         if (alg->init)
  61                 return alg->init(akcipher);
  62
  63         return 0;
  64 }
  65
  66 static void crypto_akcipher_free_instance(struct crypto_instance *inst)
  67 {
  68         struct akcipher_instance *akcipher = akcipher_instance(inst);
  69
  70         akcipher->free(akcipher);
  71 }
  72
  73 static int __maybe_unused crypto_akcipher_report_stat(
  74         struct sk_buff *skb, struct crypto_alg *alg)
  75 {
  76         struct akcipher_alg *akcipher = __crypto_akcipher_alg(alg);
  77         struct crypto_istat_akcipher *istat;
  78         struct crypto_stat_akcipher rakcipher;
  79
  80         istat = akcipher_get_stat(akcipher);
  81
  82         memset(&rakcipher, 0, sizeof(rakcipher));
  83
  84         strscpy(rakcipher.type, "akcipher", sizeof(rakcipher.type));
  85         rakcipher.stat_encrypt_cnt = atomic64_read(&istat->encrypt_cnt);
  86         rakcipher.stat_encrypt_tlen = atomic64_read(&istat->encrypt_tlen);
  87         rakcipher.stat_decrypt_cnt = atomic64_read(&istat->decrypt_cnt);
  88         rakcipher.stat_decrypt_tlen = atomic64_read(&istat->decrypt_tlen);
  89         rakcipher.stat_sign_cnt = atomic64_read(&istat->sign_cnt);
  90         rakcipher.stat_verify_cnt = atomic64_read(&istat->verify_cnt);
  91         rakcipher.stat_err_cnt = atomic64_read(&istat->err_cnt);
  92
  93         return nla_put(skb, CRYPTOCFGA_STAT_AKCIPHER,
  94                        sizeof(rakcipher), &rakcipher);
  95 }
  96
  97 static const struct crypto_type crypto_akcipher_type = {
  98         .extsize = crypto_alg_extsize,
  99         .init_tfm = crypto_akcipher_init_tfm,
 100         .free = crypto_akcipher_free_instance,
 101 #ifdef CONFIG_PROC_FS
 102         .show = crypto_akcipher_show,
 103 #endif
 104 #if IS_ENABLED(CONFIG_CRYPTO_USER)
 105         .report = crypto_akcipher_report,
 106 #endif
 107 #ifdef CONFIG_CRYPTO_STATS
 108         .report_stat = crypto_akcipher_report_stat,
 109 #endif
 110         .maskclear = ~CRYPTO_ALG_TYPE_MASK,
 111         .maskset = CRYPTO_ALG_TYPE_AHASH_MASK,
 112         .type = CRYPTO_ALG_TYPE_AKCIPHER,
 113         .tfmsize = offsetof(struct crypto_akcipher, base),
 114 };
 115
 116 int crypto_grab_akcipher(struct crypto_akcipher_spawn *spawn,
 117                          struct crypto_instance *inst,
 118                          const char *name, u32 type, u32 mask)
 119 {
 120         spawn->base.frontend = &crypto_akcipher_type;
 121         return crypto_grab_spawn(&spawn->base, inst, name, type, mask);
 122 }
 123 EXPORT_SYMBOL_GPL(crypto_grab_akcipher);
 124
 125 struct crypto_akcipher *crypto_alloc_akcipher(const char *alg_name, u32 type,
 126                                               u32 mask)
 127 {
 128         return crypto_alloc_tfm(alg_name, &crypto_akcipher_type, type, mask);
 129 }
 130 EXPORT_SYMBOL_GPL(crypto_alloc_akcipher);
 131
 132 static void akcipher_prepare_alg(struct akcipher_alg *alg)
 133 {
 134         struct crypto_istat_akcipher *istat = akcipher_get_stat(alg);
 135         struct crypto_alg *base = &alg->base;
 136
 137         base->cra_type = &crypto_akcipher_type;
 138         base->cra_flags &= ~CRYPTO_ALG_TYPE_MASK;
 139         base->cra_flags |= CRYPTO_ALG_TYPE_AKCIPHER;
 140
 141         if (IS_ENABLED(CONFIG_CRYPTO_STATS))
 142                 memset(istat, 0, sizeof(*istat));
 143 }
 144
 145 static int akcipher_default_op(struct akcipher_request *req)
 146 {
 147         return -ENOSYS;
 148 }
 149
 150 static int akcipher_default_set_key(struct crypto_akcipher *tfm,
 151                                      const void *key, unsigned int keylen)
 152 {
 153         return -ENOSYS;
 154 }
 155
 156 int crypto_register_akcipher(struct akcipher_alg *alg)
 157 {
 158         struct crypto_alg *base = &alg->base;
 159
 160         if (!alg->sign)
 161                 alg->sign = akcipher_default_op;
 162         if (!alg->verify)
 163                 alg->verify = akcipher_default_op;
 164         if (!alg->encrypt)
 165                 alg->encrypt = akcipher_default_op;
 166         if (!alg->decrypt)
 167                 alg->decrypt = akcipher_default_op;
 168         if (!alg->set_priv_key)
 169                 alg->set_priv_key = akcipher_default_set_key;
 170
 171         akcipher_prepare_alg(alg);
 172         return crypto_register_alg(base);
 173 }
 174 EXPORT_SYMBOL_GPL(crypto_register_akcipher);
 175
 176 void crypto_unregister_akcipher(struct akcipher_alg *alg)
 177 {
 178         crypto_unregister_alg(&alg->base);
 179 }
 180 EXPORT_SYMBOL_GPL(crypto_unregister_akcipher);
 181
 182 int akcipher_register_instance(struct crypto_template *tmpl,
 183                                struct akcipher_instance *inst)
 184 {
 185         if (WARN_ON(!inst->free))
 186                 return -EINVAL;
 187         akcipher_prepare_alg(&inst->alg);
 188         return crypto_register_instance(tmpl, akcipher_crypto_instance(inst));
 189 }
 190 EXPORT_SYMBOL_GPL(akcipher_register_instance);
 191
 192 int crypto_akcipher_sync_prep(struct crypto_akcipher_sync_data *data)
 193 {
 194         unsigned int reqsize = crypto_akcipher_reqsize(data->tfm);
 195         struct akcipher_request *req;
 196         struct scatterlist *sg;
 197         unsigned int mlen;
 198         unsigned int len;
 199         u8 *buf;
 200
 201         if (data->dst)
 202                 mlen = max(data->slen, data->dlen);
 203         else
 204                 mlen = data->slen + data->dlen;
 205
 206         len = sizeof(*req) + reqsize + mlen;
 207         if (len < mlen)
 208                 return -EOVERFLOW;
 209
 210         req = kzalloc(len, GFP_KERNEL);
 211         if (!req)
 212                 return -ENOMEM;
 213
 214         data->req = req;
 215         akcipher_request_set_tfm(req, data->tfm);
 216
 217         buf = (u8 *)(req + 1) + reqsize;
 218         data->buf = buf;
 219         memcpy(buf, data->src, data->slen);
 220
 221         sg = &data->sg;
 222         sg_init_one(sg, buf, mlen);
 223         akcipher_request_set_crypt(req, sg, data->dst ? sg : NULL,
 224                                    data->slen, data->dlen);
 225
 226         crypto_init_wait(&data->cwait);
 227         akcipher_request_set_callback(req, CRYPTO_TFM_REQ_MAY_SLEEP,
 228                                       crypto_req_done, &data->cwait);
 229
 230         return 0;
 231 }
 232 EXPORT_SYMBOL_GPL(crypto_akcipher_sync_prep);
 233
 234 int crypto_akcipher_sync_post(struct crypto_akcipher_sync_data *data, int err)
 235 {
 236         err = crypto_wait_req(err, &data->cwait);
 237         if (data->dst)
 238                 memcpy(data->dst, data->buf, data->dlen);
 239         data->dlen = data->req->dst_len;
 240         kfree_sensitive(data->req);
 241         return err;
 242 }
 243 EXPORT_SYMBOL_GPL(crypto_akcipher_sync_post);
 244
 245 int crypto_akcipher_sync_encrypt(struct crypto_akcipher *tfm,
 246                                  const void *src, unsigned int slen,
 247                                  void *dst, unsigned int dlen)
 248 {
 249         struct crypto_akcipher_sync_data data = {
 250                 .tfm = tfm,
 251                 .src = src,
 252                 .dst = dst,
 253                 .slen = slen,
 254                 .dlen = dlen,
 255         };
 256
 257         return crypto_akcipher_sync_prep(&data) ?:
 258                crypto_akcipher_sync_post(&data,
 259                                          crypto_akcipher_encrypt(data.req));
 260 }
 261 EXPORT_SYMBOL_GPL(crypto_akcipher_sync_encrypt);
 262
 263 int crypto_akcipher_sync_decrypt(struct crypto_akcipher *tfm,
 264                                  const void *src, unsigned int slen,
 265                                  void *dst, unsigned int dlen)
 266 {
 267         struct crypto_akcipher_sync_data data = {
 268                 .tfm = tfm,
 269                 .src = src,
 270                 .dst = dst,
 271                 .slen = slen,
 272                 .dlen = dlen,
 273         };
 274
 275         return crypto_akcipher_sync_prep(&data) ?:
 276                crypto_akcipher_sync_post(&data,
 277                                          crypto_akcipher_decrypt(data.req)) ?:
 278                data.dlen;
 279 }
 280 EXPORT_SYMBOL_GPL(crypto_akcipher_sync_decrypt);
 281
 282 static void crypto_exit_akcipher_ops_sig(struct crypto_tfm *tfm)
 283 {
 284         struct crypto_akcipher **ctx = crypto_tfm_ctx(tfm);
 285
 286         crypto_free_akcipher(*ctx);
 287 }
 288
 289 int crypto_init_akcipher_ops_sig(struct crypto_tfm *tfm)
 290 {
 291         struct crypto_akcipher **ctx = crypto_tfm_ctx(tfm);
 292         struct crypto_alg *calg = tfm->__crt_alg;
 293         struct crypto_akcipher *akcipher;
 294
 295         if (!crypto_mod_get(calg))
 296                 return -EAGAIN;
 297
 298         akcipher = crypto_create_tfm(calg, &crypto_akcipher_type);
 299         if (IS_ERR(akcipher)) {
 300                 crypto_mod_put(calg);
 301                 return PTR_ERR(akcipher);
 302         }
 303
 304         *ctx = akcipher;
 305         tfm->exit = crypto_exit_akcipher_ops_sig;
 306
 307         return 0;
 308 }
 309 EXPORT_SYMBOL_GPL(crypto_init_akcipher_ops_sig);
 310
 311 MODULE_LICENSE("GPL");
 312 MODULE_DESCRIPTION("Generic public key cipher type");