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 <linux/errno.h>
   9 #include <linux/kernel.h>
  10 #include <linux/module.h>
  11 #include <linux/seq_file.h>
  12 #include <linux/slab.h>
  13 #include <linux/string.h>
  14 #include <linux/crypto.h>
  15 #include <linux/compiler.h>
  16 #include <crypto/algapi.h>
  17 #include <linux/cryptouser.h>
  18 #include <net/netlink.h>
  19 #include <crypto/akcipher.h>
  20 #include <crypto/internal/akcipher.h>
  21 #include "internal.h"
  22
  23 #ifdef CONFIG_NET
  24 static int crypto_akcipher_report(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 #else
  36 static int crypto_akcipher_report(struct sk_buff *skb, struct crypto_alg *alg)
  37 {
  38         return -ENOSYS;
  39 }
  40 #endif
  41
  42 static void crypto_akcipher_show(struct seq_file *m, struct crypto_alg *alg)
  43         __maybe_unused;
  44
  45 static void crypto_akcipher_show(struct seq_file *m, struct crypto_alg *alg)
  46 {
  47         seq_puts(m, "type         : akcipher\n");
  48 }
  49
  50 static void crypto_akcipher_exit_tfm(struct crypto_tfm *tfm)
  51 {
  52         struct crypto_akcipher *akcipher = __crypto_akcipher_tfm(tfm);
  53         struct akcipher_alg *alg = crypto_akcipher_alg(akcipher);
  54
  55         alg->exit(akcipher);
  56 }
  57
  58 static int crypto_akcipher_init_tfm(struct crypto_tfm *tfm)
  59 {
  60         struct crypto_akcipher *akcipher = __crypto_akcipher_tfm(tfm);
  61         struct akcipher_alg *alg = crypto_akcipher_alg(akcipher);
  62
  63         if (alg->exit)
  64                 akcipher->base.exit = crypto_akcipher_exit_tfm;
  65
  66         if (alg->init)
  67                 return alg->init(akcipher);
  68
  69         return 0;
  70 }
  71
  72 static void crypto_akcipher_free_instance(struct crypto_instance *inst)
  73 {
  74         struct akcipher_instance *akcipher = akcipher_instance(inst);
  75
  76         akcipher->free(akcipher);
  77 }
  78
  79 static const struct crypto_type crypto_akcipher_type = {
  80         .extsize = crypto_alg_extsize,
  81         .init_tfm = crypto_akcipher_init_tfm,
  82         .free = crypto_akcipher_free_instance,
  83 #ifdef CONFIG_PROC_FS
  84         .show = crypto_akcipher_show,
  85 #endif
  86         .report = crypto_akcipher_report,
  87         .maskclear = ~CRYPTO_ALG_TYPE_MASK,
  88         .maskset = CRYPTO_ALG_TYPE_MASK,
  89         .type = CRYPTO_ALG_TYPE_AKCIPHER,
  90         .tfmsize = offsetof(struct crypto_akcipher, base),
  91 };
  92
  93 int crypto_grab_akcipher(struct crypto_akcipher_spawn *spawn, const char *name,
  94                          u32 type, u32 mask)
  95 {
  96         spawn->base.frontend = &crypto_akcipher_type;
  97         return crypto_grab_spawn(&spawn->base, name, type, mask);
  98 }
  99 EXPORT_SYMBOL_GPL(crypto_grab_akcipher);
 100
 101 struct crypto_akcipher *crypto_alloc_akcipher(const char *alg_name, u32 type,
 102                                               u32 mask)
 103 {
 104         return crypto_alloc_tfm(alg_name, &crypto_akcipher_type, type, mask);
 105 }
 106 EXPORT_SYMBOL_GPL(crypto_alloc_akcipher);
 107
 108 static void akcipher_prepare_alg(struct akcipher_alg *alg)
 109 {
 110         struct crypto_alg *base = &alg->base;
 111
 112         base->cra_type = &crypto_akcipher_type;
 113         base->cra_flags &= ~CRYPTO_ALG_TYPE_MASK;
 114         base->cra_flags |= CRYPTO_ALG_TYPE_AKCIPHER;
 115 }
 116
 117 static int akcipher_default_op(struct akcipher_request *req)
 118 {
 119         return -ENOSYS;
 120 }
 121
 122 int crypto_register_akcipher(struct akcipher_alg *alg)
 123 {
 124         struct crypto_alg *base = &alg->base;
 125
 126         if (!alg->sign)
 127                 alg->sign = akcipher_default_op;
 128         if (!alg->verify)
 129                 alg->verify = akcipher_default_op;
 130         if (!alg->encrypt)
 131                 alg->encrypt = akcipher_default_op;
 132         if (!alg->decrypt)
 133                 alg->decrypt = akcipher_default_op;
 134
 135         akcipher_prepare_alg(alg);
 136         return crypto_register_alg(base);
 137 }
 138 EXPORT_SYMBOL_GPL(crypto_register_akcipher);
 139
 140 void crypto_unregister_akcipher(struct akcipher_alg *alg)
 141 {
 142         crypto_unregister_alg(&alg->base);
 143 }
 144 EXPORT_SYMBOL_GPL(crypto_unregister_akcipher);
 145
 146 int akcipher_register_instance(struct crypto_template *tmpl,
 147                                struct akcipher_instance *inst)
 148 {
 149         akcipher_prepare_alg(&inst->alg);
 150         return crypto_register_instance(tmpl, akcipher_crypto_instance(inst));
 151 }
 152 EXPORT_SYMBOL_GPL(akcipher_register_instance);
 153
 154 MODULE_LICENSE("GPL");
 155 MODULE_DESCRIPTION("Generic public key cipher type");