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 const struct crypto_type crypto_akcipher_type = { 74 .extsize = crypto_alg_extsize, 75 .init_tfm = crypto_akcipher_init_tfm, 76 .free = crypto_akcipher_free_instance, 77 #ifdef CONFIG_PROC_FS 78 .show = crypto_akcipher_show, 79 #endif 80 #if IS_ENABLED(CONFIG_CRYPTO_USER) 81 .report = crypto_akcipher_report, 82 #endif 83 .maskclear = ~CRYPTO_ALG_TYPE_MASK, 84 .maskset = CRYPTO_ALG_TYPE_AHASH_MASK, 85 .type = CRYPTO_ALG_TYPE_AKCIPHER, 86 .tfmsize = offsetof(struct crypto_akcipher, base), 87 }; 88 89 int crypto_grab_akcipher(struct crypto_akcipher_spawn *spawn, 90 struct crypto_instance *inst, 91 const char *name, u32 type, u32 mask) 92 { 93 spawn->base.frontend = &crypto_akcipher_type; 94 return crypto_grab_spawn(&spawn->base, inst, name, type, mask); 95 } 96 EXPORT_SYMBOL_GPL(crypto_grab_akcipher); 97 98 struct crypto_akcipher *crypto_alloc_akcipher(const char *alg_name, u32 type, 99 u32 mask) 100 { 101 return crypto_alloc_tfm(alg_name, &crypto_akcipher_type, type, mask); 102 } 103 EXPORT_SYMBOL_GPL(crypto_alloc_akcipher); 104 105 static void akcipher_prepare_alg(struct akcipher_alg *alg) 106 { 107 struct crypto_alg *base = &alg->base; 108 109 base->cra_type = &crypto_akcipher_type; 110 base->cra_flags &= ~CRYPTO_ALG_TYPE_MASK; 111 base->cra_flags |= CRYPTO_ALG_TYPE_AKCIPHER; 112 } 113 114 static int akcipher_default_op(struct akcipher_request *req) 115 { 116 return -ENOSYS; 117 } 118 119 static int akcipher_default_set_key(struct crypto_akcipher *tfm, 120 const void *key, unsigned int keylen) 121 { 122 return -ENOSYS; 123 } 124 125 int crypto_register_akcipher(struct akcipher_alg *alg) 126 { 127 struct crypto_alg *base = &alg->base; 128 129 if (!alg->sign) 130 alg->sign = akcipher_default_op; 131 if (!alg->verify) 132 alg->verify = akcipher_default_op; 133 if (!alg->encrypt) 134 alg->encrypt = akcipher_default_op; 135 if (!alg->decrypt) 136 alg->decrypt = akcipher_default_op; 137 if (!alg->set_priv_key) 138 alg->set_priv_key = akcipher_default_set_key; 139 140 akcipher_prepare_alg(alg); 141 return crypto_register_alg(base); 142 } 143 EXPORT_SYMBOL_GPL(crypto_register_akcipher); 144 145 void crypto_unregister_akcipher(struct akcipher_alg *alg) 146 { 147 crypto_unregister_alg(&alg->base); 148 } 149 EXPORT_SYMBOL_GPL(crypto_unregister_akcipher); 150 151 int akcipher_register_instance(struct crypto_template *tmpl, 152 struct akcipher_instance *inst) 153 { 154 if (WARN_ON(!inst->free)) 155 return -EINVAL; 156 akcipher_prepare_alg(&inst->alg); 157 return crypto_register_instance(tmpl, akcipher_crypto_instance(inst)); 158 } 159 EXPORT_SYMBOL_GPL(akcipher_register_instance); 160 161 int crypto_akcipher_sync_prep(struct crypto_akcipher_sync_data *data) 162 { 163 unsigned int reqsize = crypto_akcipher_reqsize(data->tfm); 164 struct akcipher_request *req; 165 struct scatterlist *sg; 166 unsigned int mlen; 167 unsigned int len; 168 u8 *buf; 169 170 if (data->dst) 171 mlen = max(data->slen, data->dlen); 172 else 173 mlen = data->slen + data->dlen; 174 175 len = sizeof(*req) + reqsize + mlen; 176 if (len < mlen) 177 return -EOVERFLOW; 178 179 req = kzalloc(len, GFP_KERNEL); 180 if (!req) 181 return -ENOMEM; 182 183 data->req = req; 184 akcipher_request_set_tfm(req, data->tfm); 185 186 buf = (u8 *)(req + 1) + reqsize; 187 data->buf = buf; 188 memcpy(buf, data->src, data->slen); 189 190 sg = &data->sg; 191 sg_init_one(sg, buf, mlen); 192 akcipher_request_set_crypt(req, sg, data->dst ? sg : NULL, 193 data->slen, data->dlen); 194 195 crypto_init_wait(&data->cwait); 196 akcipher_request_set_callback(req, CRYPTO_TFM_REQ_MAY_SLEEP, 197 crypto_req_done, &data->cwait); 198 199 return 0; 200 } 201 EXPORT_SYMBOL_GPL(crypto_akcipher_sync_prep); 202 203 int crypto_akcipher_sync_post(struct crypto_akcipher_sync_data *data, int err) 204 { 205 err = crypto_wait_req(err, &data->cwait); 206 if (data->dst) 207 memcpy(data->dst, data->buf, data->dlen); 208 data->dlen = data->req->dst_len; 209 kfree_sensitive(data->req); 210 return err; 211 } 212 EXPORT_SYMBOL_GPL(crypto_akcipher_sync_post); 213 214 int crypto_akcipher_sync_encrypt(struct crypto_akcipher *tfm, 215 const void *src, unsigned int slen, 216 void *dst, unsigned int dlen) 217 { 218 struct crypto_akcipher_sync_data data = { 219 .tfm = tfm, 220 .src = src, 221 .dst = dst, 222 .slen = slen, 223 .dlen = dlen, 224 }; 225 226 return crypto_akcipher_sync_prep(&data) ?: 227 crypto_akcipher_sync_post(&data, 228 crypto_akcipher_encrypt(data.req)); 229 } 230 EXPORT_SYMBOL_GPL(crypto_akcipher_sync_encrypt); 231 232 int crypto_akcipher_sync_decrypt(struct crypto_akcipher *tfm, 233 const void *src, unsigned int slen, 234 void *dst, unsigned int dlen) 235 { 236 struct crypto_akcipher_sync_data data = { 237 .tfm = tfm, 238 .src = src, 239 .dst = dst, 240 .slen = slen, 241 .dlen = dlen, 242 }; 243 244 return crypto_akcipher_sync_prep(&data) ?: 245 crypto_akcipher_sync_post(&data, 246 crypto_akcipher_decrypt(data.req)) ?: 247 data.dlen; 248 } 249 EXPORT_SYMBOL_GPL(crypto_akcipher_sync_decrypt); 250 251 static void crypto_exit_akcipher_ops_sig(struct crypto_tfm *tfm) 252 { 253 struct crypto_akcipher **ctx = crypto_tfm_ctx(tfm); 254 255 crypto_free_akcipher(*ctx); 256 } 257 258 int crypto_init_akcipher_ops_sig(struct crypto_tfm *tfm) 259 { 260 struct crypto_akcipher **ctx = crypto_tfm_ctx(tfm); 261 struct crypto_alg *calg = tfm->__crt_alg; 262 struct crypto_akcipher *akcipher; 263 264 if (!crypto_mod_get(calg)) 265 return -EAGAIN; 266 267 akcipher = crypto_create_tfm(calg, &crypto_akcipher_type); 268 if (IS_ERR(akcipher)) { 269 crypto_mod_put(calg); 270 return PTR_ERR(akcipher); 271 } 272 273 *ctx = akcipher; 274 tfm->exit = crypto_exit_akcipher_ops_sig; 275 276 return 0; 277 } 278 EXPORT_SYMBOL_GPL(crypto_init_akcipher_ops_sig); 279 280 MODULE_LICENSE("GPL"); 281 MODULE_DESCRIPTION("Generic public key cipher type"); 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