Mikko Herranen | 28db8e3 | 2007-11-26 22:24:11 +0800 | [diff] [blame] | 1 | /* |
| 2 | * GCM: Galois/Counter Mode. |
| 3 | * |
| 4 | * Copyright (c) 2007 Nokia Siemens Networks - Mikko Herranen <mh1@iki.fi> |
| 5 | * |
| 6 | * This program is free software; you can redistribute it and/or modify it |
| 7 | * under the terms of the GNU General Public License version 2 as published |
| 8 | * by the Free Software Foundation. |
| 9 | */ |
| 10 | |
| 11 | #include <crypto/algapi.h> |
| 12 | #include <crypto/gf128mul.h> |
| 13 | #include <linux/err.h> |
| 14 | #include <linux/init.h> |
| 15 | #include <linux/kernel.h> |
| 16 | #include <linux/module.h> |
| 17 | #include <linux/slab.h> |
| 18 | |
| 19 | #include "scatterwalk.h" |
| 20 | |
| 21 | struct gcm_instance_ctx { |
| 22 | struct crypto_spawn ctr; |
| 23 | }; |
| 24 | |
| 25 | struct crypto_gcm_ctx { |
| 26 | struct crypto_ablkcipher *ctr; |
| 27 | struct gf128mul_4k *gf128; |
| 28 | }; |
| 29 | |
| 30 | struct crypto_gcm_ghash_ctx { |
| 31 | u32 bytes; |
| 32 | u32 flags; |
| 33 | struct gf128mul_4k *gf128; |
| 34 | u8 buffer[16]; |
| 35 | }; |
| 36 | |
| 37 | struct crypto_gcm_req_priv_ctx { |
| 38 | u8 auth_tag[16]; |
Herbert Xu | 6160b28 | 2007-12-04 19:17:50 +1100 | [diff] [blame] | 39 | u8 iauth_tag[16]; |
Mikko Herranen | 28db8e3 | 2007-11-26 22:24:11 +0800 | [diff] [blame] | 40 | u8 counter[16]; |
| 41 | struct crypto_gcm_ghash_ctx ghash; |
| 42 | }; |
| 43 | |
| 44 | static void crypto_gcm_ghash_init(struct crypto_gcm_ghash_ctx *ctx, u32 flags, |
| 45 | struct gf128mul_4k *gf128) |
| 46 | { |
| 47 | ctx->bytes = 0; |
| 48 | ctx->flags = flags; |
| 49 | ctx->gf128 = gf128; |
| 50 | memset(ctx->buffer, 0, 16); |
| 51 | } |
| 52 | |
| 53 | static void crypto_gcm_ghash_update(struct crypto_gcm_ghash_ctx *ctx, |
| 54 | const u8 *src, unsigned int srclen) |
| 55 | { |
| 56 | u8 *dst = ctx->buffer; |
| 57 | |
| 58 | if (ctx->bytes) { |
| 59 | int n = min(srclen, ctx->bytes); |
| 60 | u8 *pos = dst + (16 - ctx->bytes); |
| 61 | |
| 62 | ctx->bytes -= n; |
| 63 | srclen -= n; |
| 64 | |
| 65 | while (n--) |
| 66 | *pos++ ^= *src++; |
| 67 | |
| 68 | if (!ctx->bytes) |
| 69 | gf128mul_4k_lle((be128 *)dst, ctx->gf128); |
| 70 | } |
| 71 | |
| 72 | while (srclen >= 16) { |
| 73 | crypto_xor(dst, src, 16); |
| 74 | gf128mul_4k_lle((be128 *)dst, ctx->gf128); |
| 75 | src += 16; |
| 76 | srclen -= 16; |
| 77 | } |
| 78 | |
| 79 | if (srclen) { |
| 80 | ctx->bytes = 16 - srclen; |
| 81 | while (srclen--) |
| 82 | *dst++ ^= *src++; |
| 83 | } |
| 84 | } |
| 85 | |
| 86 | static void crypto_gcm_ghash_update_sg(struct crypto_gcm_ghash_ctx *ctx, |
| 87 | struct scatterlist *sg, int len) |
| 88 | { |
| 89 | struct scatter_walk walk; |
| 90 | u8 *src; |
| 91 | int n; |
| 92 | |
Herbert Xu | 6160b28 | 2007-12-04 19:17:50 +1100 | [diff] [blame] | 93 | if (!len) |
| 94 | return; |
| 95 | |
Mikko Herranen | 28db8e3 | 2007-11-26 22:24:11 +0800 | [diff] [blame] | 96 | scatterwalk_start(&walk, sg); |
| 97 | |
| 98 | while (len) { |
| 99 | n = scatterwalk_clamp(&walk, len); |
| 100 | |
| 101 | if (!n) { |
| 102 | scatterwalk_start(&walk, sg_next(walk.sg)); |
| 103 | n = scatterwalk_clamp(&walk, len); |
| 104 | } |
| 105 | |
| 106 | src = scatterwalk_map(&walk, 0); |
| 107 | |
| 108 | crypto_gcm_ghash_update(ctx, src, n); |
| 109 | len -= n; |
| 110 | |
| 111 | scatterwalk_unmap(src, 0); |
| 112 | scatterwalk_advance(&walk, n); |
| 113 | scatterwalk_done(&walk, 0, len); |
| 114 | if (len) |
| 115 | crypto_yield(ctx->flags); |
| 116 | } |
| 117 | } |
| 118 | |
| 119 | static void crypto_gcm_ghash_flush(struct crypto_gcm_ghash_ctx *ctx) |
| 120 | { |
| 121 | u8 *dst = ctx->buffer; |
| 122 | |
| 123 | if (ctx->bytes) { |
| 124 | u8 *tmp = dst + (16 - ctx->bytes); |
| 125 | |
| 126 | while (ctx->bytes--) |
| 127 | *tmp++ ^= 0; |
| 128 | |
| 129 | gf128mul_4k_lle((be128 *)dst, ctx->gf128); |
| 130 | } |
| 131 | |
| 132 | ctx->bytes = 0; |
| 133 | } |
| 134 | |
| 135 | static void crypto_gcm_ghash_final_xor(struct crypto_gcm_ghash_ctx *ctx, |
| 136 | unsigned int authlen, |
| 137 | unsigned int cryptlen, u8 *dst) |
| 138 | { |
| 139 | u8 *buf = ctx->buffer; |
| 140 | u128 lengths; |
| 141 | |
| 142 | lengths.a = cpu_to_be64(authlen * 8); |
| 143 | lengths.b = cpu_to_be64(cryptlen * 8); |
| 144 | |
| 145 | crypto_gcm_ghash_flush(ctx); |
| 146 | crypto_xor(buf, (u8 *)&lengths, 16); |
| 147 | gf128mul_4k_lle((be128 *)buf, ctx->gf128); |
| 148 | crypto_xor(dst, buf, 16); |
| 149 | } |
| 150 | |
| 151 | static inline void crypto_gcm_set_counter(u8 *counterblock, u32 value) |
| 152 | { |
| 153 | *((u32 *)&counterblock[12]) = cpu_to_be32(value); |
| 154 | } |
| 155 | |
| 156 | static int crypto_gcm_encrypt_counter(struct crypto_aead *aead, u8 *block, |
| 157 | u32 value, const u8 *iv) |
| 158 | { |
| 159 | struct crypto_gcm_ctx *ctx = crypto_aead_ctx(aead); |
| 160 | struct crypto_ablkcipher *ctr = ctx->ctr; |
| 161 | struct ablkcipher_request req; |
| 162 | struct scatterlist sg; |
| 163 | u8 counterblock[16]; |
| 164 | |
| 165 | if (iv == NULL) |
| 166 | memset(counterblock, 0, 12); |
| 167 | else |
| 168 | memcpy(counterblock, iv, 12); |
| 169 | |
| 170 | crypto_gcm_set_counter(counterblock, value); |
| 171 | |
| 172 | sg_init_one(&sg, block, 16); |
| 173 | ablkcipher_request_set_tfm(&req, ctr); |
| 174 | ablkcipher_request_set_crypt(&req, &sg, &sg, 16, counterblock); |
| 175 | ablkcipher_request_set_callback(&req, 0, NULL, NULL); |
| 176 | memset(block, 0, 16); |
| 177 | return crypto_ablkcipher_encrypt(&req); |
| 178 | } |
| 179 | |
| 180 | static int crypto_gcm_setkey(struct crypto_aead *aead, const u8 *key, |
| 181 | unsigned int keylen) |
| 182 | { |
| 183 | struct crypto_gcm_ctx *ctx = crypto_aead_ctx(aead); |
| 184 | struct crypto_ablkcipher *ctr = ctx->ctr; |
| 185 | int alignmask = crypto_ablkcipher_alignmask(ctr); |
| 186 | u8 alignbuf[16+alignmask]; |
| 187 | u8 *hash = (u8 *)ALIGN((unsigned long)alignbuf, alignmask+1); |
| 188 | int err = 0; |
| 189 | |
| 190 | crypto_ablkcipher_clear_flags(ctr, CRYPTO_TFM_REQ_MASK); |
| 191 | crypto_ablkcipher_set_flags(ctr, crypto_aead_get_flags(aead) & |
| 192 | CRYPTO_TFM_REQ_MASK); |
| 193 | |
| 194 | err = crypto_ablkcipher_setkey(ctr, key, keylen); |
| 195 | if (err) |
| 196 | goto out; |
| 197 | |
| 198 | crypto_aead_set_flags(aead, crypto_ablkcipher_get_flags(ctr) & |
| 199 | CRYPTO_TFM_RES_MASK); |
| 200 | |
| 201 | err = crypto_gcm_encrypt_counter(aead, hash, -1, NULL); |
| 202 | if (err) |
| 203 | goto out; |
| 204 | |
| 205 | if (ctx->gf128 != NULL) |
| 206 | gf128mul_free_4k(ctx->gf128); |
| 207 | |
| 208 | ctx->gf128 = gf128mul_init_4k_lle((be128 *)hash); |
| 209 | |
| 210 | if (ctx->gf128 == NULL) |
| 211 | err = -ENOMEM; |
| 212 | |
| 213 | out: |
| 214 | return err; |
| 215 | } |
| 216 | |
| 217 | static int crypto_gcm_init_crypt(struct ablkcipher_request *ablk_req, |
Herbert Xu | 6160b28 | 2007-12-04 19:17:50 +1100 | [diff] [blame] | 218 | struct aead_request *req, |
| 219 | unsigned int cryptlen, |
| 220 | void (*done)(struct crypto_async_request *, |
| 221 | int)) |
Mikko Herranen | 28db8e3 | 2007-11-26 22:24:11 +0800 | [diff] [blame] | 222 | { |
| 223 | struct crypto_aead *aead = crypto_aead_reqtfm(req); |
| 224 | struct crypto_gcm_ctx *ctx = crypto_aead_ctx(aead); |
| 225 | struct crypto_gcm_req_priv_ctx *pctx = aead_request_ctx(req); |
| 226 | u32 flags = req->base.tfm->crt_flags; |
| 227 | u8 *auth_tag = pctx->auth_tag; |
| 228 | u8 *counter = pctx->counter; |
| 229 | struct crypto_gcm_ghash_ctx *ghash = &pctx->ghash; |
| 230 | int err = 0; |
| 231 | |
| 232 | ablkcipher_request_set_tfm(ablk_req, ctx->ctr); |
| 233 | ablkcipher_request_set_callback(ablk_req, aead_request_flags(req), |
| 234 | done, req); |
| 235 | ablkcipher_request_set_crypt(ablk_req, req->src, req->dst, |
Herbert Xu | 6160b28 | 2007-12-04 19:17:50 +1100 | [diff] [blame] | 236 | cryptlen, counter); |
Mikko Herranen | 28db8e3 | 2007-11-26 22:24:11 +0800 | [diff] [blame] | 237 | |
| 238 | err = crypto_gcm_encrypt_counter(aead, auth_tag, 0, req->iv); |
| 239 | if (err) |
| 240 | goto out; |
| 241 | |
| 242 | memcpy(counter, req->iv, 12); |
| 243 | crypto_gcm_set_counter(counter, 1); |
| 244 | |
| 245 | crypto_gcm_ghash_init(ghash, flags, ctx->gf128); |
| 246 | |
Herbert Xu | 6160b28 | 2007-12-04 19:17:50 +1100 | [diff] [blame] | 247 | crypto_gcm_ghash_update_sg(ghash, req->assoc, req->assoclen); |
| 248 | crypto_gcm_ghash_flush(ghash); |
Mikko Herranen | 28db8e3 | 2007-11-26 22:24:11 +0800 | [diff] [blame] | 249 | |
| 250 | out: |
| 251 | return err; |
| 252 | } |
| 253 | |
Herbert Xu | 6160b28 | 2007-12-04 19:17:50 +1100 | [diff] [blame] | 254 | static int crypto_gcm_hash(struct aead_request *req) |
Mikko Herranen | 28db8e3 | 2007-11-26 22:24:11 +0800 | [diff] [blame] | 255 | { |
Herbert Xu | 6160b28 | 2007-12-04 19:17:50 +1100 | [diff] [blame] | 256 | struct crypto_aead *aead = crypto_aead_reqtfm(req); |
Mikko Herranen | 28db8e3 | 2007-11-26 22:24:11 +0800 | [diff] [blame] | 257 | struct crypto_gcm_req_priv_ctx *pctx = aead_request_ctx(req); |
| 258 | u8 *auth_tag = pctx->auth_tag; |
| 259 | struct crypto_gcm_ghash_ctx *ghash = &pctx->ghash; |
| 260 | |
| 261 | crypto_gcm_ghash_update_sg(ghash, req->dst, req->cryptlen); |
| 262 | crypto_gcm_ghash_final_xor(ghash, req->assoclen, req->cryptlen, |
| 263 | auth_tag); |
| 264 | |
Herbert Xu | 6160b28 | 2007-12-04 19:17:50 +1100 | [diff] [blame] | 265 | scatterwalk_map_and_copy(auth_tag, req->dst, req->cryptlen, |
| 266 | crypto_aead_authsize(aead), 1); |
| 267 | return 0; |
| 268 | } |
| 269 | |
| 270 | static void crypto_gcm_encrypt_done(struct crypto_async_request *areq, int err) |
| 271 | { |
| 272 | struct aead_request *req = areq->data; |
| 273 | |
| 274 | if (!err) |
| 275 | err = crypto_gcm_hash(req); |
| 276 | |
Mikko Herranen | 28db8e3 | 2007-11-26 22:24:11 +0800 | [diff] [blame] | 277 | aead_request_complete(req, err); |
| 278 | } |
| 279 | |
| 280 | static int crypto_gcm_encrypt(struct aead_request *req) |
| 281 | { |
| 282 | struct ablkcipher_request abreq; |
Mikko Herranen | 28db8e3 | 2007-11-26 22:24:11 +0800 | [diff] [blame] | 283 | int err = 0; |
| 284 | |
Herbert Xu | 6160b28 | 2007-12-04 19:17:50 +1100 | [diff] [blame] | 285 | err = crypto_gcm_init_crypt(&abreq, req, req->cryptlen, |
| 286 | crypto_gcm_encrypt_done); |
Mikko Herranen | 28db8e3 | 2007-11-26 22:24:11 +0800 | [diff] [blame] | 287 | if (err) |
| 288 | return err; |
| 289 | |
| 290 | if (req->cryptlen) { |
| 291 | err = crypto_ablkcipher_encrypt(&abreq); |
| 292 | if (err) |
| 293 | return err; |
Mikko Herranen | 28db8e3 | 2007-11-26 22:24:11 +0800 | [diff] [blame] | 294 | } |
| 295 | |
Herbert Xu | 6160b28 | 2007-12-04 19:17:50 +1100 | [diff] [blame] | 296 | return crypto_gcm_hash(req); |
Mikko Herranen | 28db8e3 | 2007-11-26 22:24:11 +0800 | [diff] [blame] | 297 | } |
| 298 | |
| 299 | static void crypto_gcm_decrypt_done(struct crypto_async_request *areq, int err) |
| 300 | { |
| 301 | aead_request_complete(areq->data, err); |
| 302 | } |
| 303 | |
| 304 | static int crypto_gcm_decrypt(struct aead_request *req) |
| 305 | { |
| 306 | struct ablkcipher_request abreq; |
Herbert Xu | 6160b28 | 2007-12-04 19:17:50 +1100 | [diff] [blame] | 307 | struct crypto_aead *aead = crypto_aead_reqtfm(req); |
Mikko Herranen | 28db8e3 | 2007-11-26 22:24:11 +0800 | [diff] [blame] | 308 | struct crypto_gcm_req_priv_ctx *pctx = aead_request_ctx(req); |
| 309 | u8 *auth_tag = pctx->auth_tag; |
Herbert Xu | 6160b28 | 2007-12-04 19:17:50 +1100 | [diff] [blame] | 310 | u8 *iauth_tag = pctx->iauth_tag; |
Mikko Herranen | 28db8e3 | 2007-11-26 22:24:11 +0800 | [diff] [blame] | 311 | struct crypto_gcm_ghash_ctx *ghash = &pctx->ghash; |
Herbert Xu | 6160b28 | 2007-12-04 19:17:50 +1100 | [diff] [blame] | 312 | unsigned int cryptlen = req->cryptlen; |
| 313 | unsigned int authsize = crypto_aead_authsize(aead); |
Mikko Herranen | 28db8e3 | 2007-11-26 22:24:11 +0800 | [diff] [blame] | 314 | int err; |
| 315 | |
Herbert Xu | 6160b28 | 2007-12-04 19:17:50 +1100 | [diff] [blame] | 316 | if (cryptlen < authsize) |
Mikko Herranen | 28db8e3 | 2007-11-26 22:24:11 +0800 | [diff] [blame] | 317 | return -EINVAL; |
Herbert Xu | 6160b28 | 2007-12-04 19:17:50 +1100 | [diff] [blame] | 318 | cryptlen -= authsize; |
Mikko Herranen | 28db8e3 | 2007-11-26 22:24:11 +0800 | [diff] [blame] | 319 | |
Herbert Xu | 6160b28 | 2007-12-04 19:17:50 +1100 | [diff] [blame] | 320 | err = crypto_gcm_init_crypt(&abreq, req, cryptlen, |
| 321 | crypto_gcm_decrypt_done); |
Mikko Herranen | 28db8e3 | 2007-11-26 22:24:11 +0800 | [diff] [blame] | 322 | if (err) |
| 323 | return err; |
| 324 | |
Herbert Xu | 6160b28 | 2007-12-04 19:17:50 +1100 | [diff] [blame] | 325 | crypto_gcm_ghash_update_sg(ghash, req->src, cryptlen); |
| 326 | crypto_gcm_ghash_final_xor(ghash, req->assoclen, cryptlen, auth_tag); |
Mikko Herranen | 28db8e3 | 2007-11-26 22:24:11 +0800 | [diff] [blame] | 327 | |
Herbert Xu | 6160b28 | 2007-12-04 19:17:50 +1100 | [diff] [blame] | 328 | scatterwalk_map_and_copy(iauth_tag, req->src, cryptlen, authsize, 0); |
| 329 | if (memcmp(iauth_tag, auth_tag, authsize)) |
Herbert Xu | fe70f5d | 2007-12-04 20:07:27 +1100 | [diff] [blame^] | 330 | return -EBADMSG; |
Mikko Herranen | 28db8e3 | 2007-11-26 22:24:11 +0800 | [diff] [blame] | 331 | |
| 332 | return crypto_ablkcipher_decrypt(&abreq); |
| 333 | } |
| 334 | |
| 335 | static int crypto_gcm_init_tfm(struct crypto_tfm *tfm) |
| 336 | { |
| 337 | struct crypto_instance *inst = (void *)tfm->__crt_alg; |
| 338 | struct gcm_instance_ctx *ictx = crypto_instance_ctx(inst); |
| 339 | struct crypto_gcm_ctx *ctx = crypto_tfm_ctx(tfm); |
| 340 | struct crypto_ablkcipher *ctr; |
| 341 | unsigned long align; |
| 342 | int err; |
| 343 | |
| 344 | ctr = crypto_spawn_ablkcipher(&ictx->ctr); |
| 345 | err = PTR_ERR(ctr); |
| 346 | if (IS_ERR(ctr)) |
| 347 | return err; |
| 348 | |
| 349 | ctx->ctr = ctr; |
| 350 | ctx->gf128 = NULL; |
| 351 | |
| 352 | align = max_t(unsigned long, crypto_ablkcipher_alignmask(ctr), |
| 353 | __alignof__(u32) - 1); |
| 354 | align &= ~(crypto_tfm_ctx_alignment() - 1); |
| 355 | tfm->crt_aead.reqsize = align + sizeof(struct crypto_gcm_req_priv_ctx); |
| 356 | |
| 357 | return 0; |
| 358 | } |
| 359 | |
| 360 | static void crypto_gcm_exit_tfm(struct crypto_tfm *tfm) |
| 361 | { |
| 362 | struct crypto_gcm_ctx *ctx = crypto_tfm_ctx(tfm); |
| 363 | |
| 364 | if (ctx->gf128 != NULL) |
| 365 | gf128mul_free_4k(ctx->gf128); |
| 366 | |
| 367 | crypto_free_ablkcipher(ctx->ctr); |
| 368 | } |
| 369 | |
| 370 | static struct crypto_instance *crypto_gcm_alloc(struct rtattr **tb) |
| 371 | { |
| 372 | struct crypto_instance *inst; |
| 373 | struct crypto_alg *ctr; |
| 374 | struct crypto_alg *cipher; |
| 375 | struct gcm_instance_ctx *ctx; |
| 376 | int err; |
| 377 | char ctr_name[CRYPTO_MAX_ALG_NAME]; |
| 378 | |
| 379 | err = crypto_check_attr_type(tb, CRYPTO_ALG_TYPE_AEAD); |
| 380 | if (err) |
| 381 | return ERR_PTR(err); |
| 382 | |
| 383 | cipher = crypto_attr_alg(tb[1], CRYPTO_ALG_TYPE_CIPHER, |
| 384 | CRYPTO_ALG_TYPE_MASK); |
| 385 | |
| 386 | inst = ERR_PTR(PTR_ERR(cipher)); |
| 387 | if (IS_ERR(cipher)) |
| 388 | return inst; |
| 389 | |
| 390 | inst = ERR_PTR(ENAMETOOLONG); |
| 391 | if (snprintf( |
| 392 | ctr_name, CRYPTO_MAX_ALG_NAME, |
| 393 | "ctr(%s,0,16,4)", cipher->cra_name) >= CRYPTO_MAX_ALG_NAME) |
| 394 | return inst; |
| 395 | |
| 396 | ctr = crypto_alg_mod_lookup(ctr_name, CRYPTO_ALG_TYPE_BLKCIPHER, |
| 397 | CRYPTO_ALG_TYPE_MASK); |
| 398 | |
| 399 | if (IS_ERR(ctr)) |
| 400 | return ERR_PTR(PTR_ERR(ctr)); |
| 401 | |
| 402 | if (cipher->cra_blocksize != 16) |
| 403 | goto out_put_ctr; |
| 404 | |
| 405 | inst = kzalloc(sizeof(*inst) + sizeof(*ctx), GFP_KERNEL); |
| 406 | err = -ENOMEM; |
| 407 | if (!inst) |
| 408 | goto out_put_ctr; |
| 409 | |
| 410 | err = -ENAMETOOLONG; |
| 411 | if (snprintf(inst->alg.cra_name, CRYPTO_MAX_ALG_NAME, |
| 412 | "gcm(%s)", cipher->cra_name) >= CRYPTO_MAX_ALG_NAME || |
| 413 | snprintf(inst->alg.cra_driver_name, CRYPTO_MAX_ALG_NAME, |
| 414 | "gcm(%s)", cipher->cra_driver_name) >= CRYPTO_MAX_ALG_NAME) |
| 415 | goto err_free_inst; |
| 416 | |
| 417 | |
| 418 | ctx = crypto_instance_ctx(inst); |
| 419 | err = crypto_init_spawn(&ctx->ctr, ctr, inst, CRYPTO_ALG_TYPE_MASK); |
| 420 | if (err) |
| 421 | goto err_free_inst; |
| 422 | |
| 423 | inst->alg.cra_flags = CRYPTO_ALG_TYPE_AEAD | CRYPTO_ALG_ASYNC; |
| 424 | inst->alg.cra_priority = ctr->cra_priority; |
| 425 | inst->alg.cra_blocksize = 16; |
| 426 | inst->alg.cra_alignmask = __alignof__(u32) - 1; |
| 427 | inst->alg.cra_type = &crypto_aead_type; |
| 428 | inst->alg.cra_aead.ivsize = 12; |
Herbert Xu | 7ba683a | 2007-12-02 18:49:21 +1100 | [diff] [blame] | 429 | inst->alg.cra_aead.maxauthsize = 16; |
Mikko Herranen | 28db8e3 | 2007-11-26 22:24:11 +0800 | [diff] [blame] | 430 | inst->alg.cra_ctxsize = sizeof(struct crypto_gcm_ctx); |
| 431 | inst->alg.cra_init = crypto_gcm_init_tfm; |
| 432 | inst->alg.cra_exit = crypto_gcm_exit_tfm; |
| 433 | inst->alg.cra_aead.setkey = crypto_gcm_setkey; |
| 434 | inst->alg.cra_aead.encrypt = crypto_gcm_encrypt; |
| 435 | inst->alg.cra_aead.decrypt = crypto_gcm_decrypt; |
| 436 | |
| 437 | out: |
| 438 | crypto_mod_put(ctr); |
| 439 | return inst; |
| 440 | err_free_inst: |
| 441 | kfree(inst); |
| 442 | out_put_ctr: |
| 443 | inst = ERR_PTR(err); |
| 444 | goto out; |
| 445 | } |
| 446 | |
| 447 | static void crypto_gcm_free(struct crypto_instance *inst) |
| 448 | { |
| 449 | struct gcm_instance_ctx *ctx = crypto_instance_ctx(inst); |
| 450 | |
| 451 | crypto_drop_spawn(&ctx->ctr); |
| 452 | kfree(inst); |
| 453 | } |
| 454 | |
| 455 | static struct crypto_template crypto_gcm_tmpl = { |
| 456 | .name = "gcm", |
| 457 | .alloc = crypto_gcm_alloc, |
| 458 | .free = crypto_gcm_free, |
| 459 | .module = THIS_MODULE, |
| 460 | }; |
| 461 | |
| 462 | static int __init crypto_gcm_module_init(void) |
| 463 | { |
| 464 | return crypto_register_template(&crypto_gcm_tmpl); |
| 465 | } |
| 466 | |
| 467 | static void __exit crypto_gcm_module_exit(void) |
| 468 | { |
| 469 | crypto_unregister_template(&crypto_gcm_tmpl); |
| 470 | } |
| 471 | |
| 472 | module_init(crypto_gcm_module_init); |
| 473 | module_exit(crypto_gcm_module_exit); |
| 474 | |
| 475 | MODULE_LICENSE("GPL"); |
| 476 | MODULE_DESCRIPTION("Galois/Counter Mode"); |
| 477 | MODULE_AUTHOR("Mikko Herranen <mh1@iki.fi>"); |