// SPDX-License-Identifier: GPL-2.0-or-later /* * Copyright (C)2006 USAGI/WIDE Project * * Author: * Kazunori Miyazawa */ #include #include #include #include #include static u_int32_t ks[12] = {0x01010101, 0x01010101, 0x01010101, 0x01010101, 0x02020202, 0x02020202, 0x02020202, 0x02020202, 0x03030303, 0x03030303, 0x03030303, 0x03030303}; /* * +------------------------ * | * +------------------------ * | xcbc_tfm_ctx * +------------------------ * | consts (block size * 2) * +------------------------ */ struct xcbc_tfm_ctx { struct crypto_cipher *child; u8 consts[]; }; /* * +------------------------ * | * +------------------------ * | xcbc_desc_ctx * +------------------------ * | odds (block size) * +------------------------ * | prev (block size) * +------------------------ */ struct xcbc_desc_ctx { unsigned int len; u8 odds[]; }; #define XCBC_BLOCKSIZE 16 static int crypto_xcbc_digest_setkey(struct crypto_shash *parent, const u8 *inkey, unsigned int keylen) { struct xcbc_tfm_ctx *ctx = crypto_shash_ctx(parent); u8 *consts = ctx->consts; int err = 0; u8 key1[XCBC_BLOCKSIZE]; int bs = sizeof(key1); if ((err = crypto_cipher_setkey(ctx->child, inkey, keylen))) return err; crypto_cipher_encrypt_one(ctx->child, consts, (u8 *)ks + bs); crypto_cipher_encrypt_one(ctx->child, consts + bs, (u8 *)ks + bs * 2); crypto_cipher_encrypt_one(ctx->child, key1, (u8 *)ks); return crypto_cipher_setkey(ctx->child, key1, bs); } static int crypto_xcbc_digest_init(struct shash_desc *pdesc) { struct xcbc_desc_ctx *ctx = shash_desc_ctx(pdesc); int bs = crypto_shash_blocksize(pdesc->tfm); u8 *prev = &ctx->odds[bs]; ctx->len = 0; memset(prev, 0, bs); return 0; } static int crypto_xcbc_digest_update(struct shash_desc *pdesc, const u8 *p, unsigned int len) { struct crypto_shash *parent = pdesc->tfm; struct xcbc_tfm_ctx *tctx = crypto_shash_ctx(parent); struct xcbc_desc_ctx *ctx = shash_desc_ctx(pdesc); struct crypto_cipher *tfm = tctx->child; int bs = crypto_shash_blocksize(parent); u8 *odds = ctx->odds; u8 *prev = odds + bs; /* checking the data can fill the block */ if ((ctx->len + len) <= bs) { memcpy(odds + ctx->len, p, len); ctx->len += len; return 0; } /* filling odds with new data and encrypting it */ memcpy(odds + ctx->len, p, bs - ctx->len); len -= bs - ctx->len; p += bs - ctx->len; crypto_xor(prev, odds, bs); crypto_cipher_encrypt_one(tfm, prev, prev); /* clearing the length */ ctx->len = 0; /* encrypting the rest of data */ while (len > bs) { crypto_xor(prev, p, bs); crypto_cipher_encrypt_one(tfm, prev, prev); p += bs; len -= bs; } /* keeping the surplus of blocksize */ if (len) { memcpy(odds, p, len); ctx->len = len; } return 0; } static int crypto_xcbc_digest_final(struct shash_desc *pdesc, u8 *out) { struct crypto_shash *parent = pdesc->tfm; struct xcbc_tfm_ctx *tctx = crypto_shash_ctx(parent); struct xcbc_desc_ctx *ctx = shash_desc_ctx(pdesc); struct crypto_cipher *tfm = tctx->child; int bs = crypto_shash_blocksize(parent); u8 *odds = ctx->odds; u8 *prev = odds + bs; unsigned int offset = 0; if (ctx->len != bs) { unsigned int rlen; u8 *p = odds + ctx->len; *p = 0x80; p++; rlen = bs - ctx->len -1; if (rlen) memset(p, 0, rlen); offset += bs; } crypto_xor(prev, odds, bs); crypto_xor(prev, &tctx->consts[offset], bs); crypto_cipher_encrypt_one(tfm, out, prev); return 0; } static int xcbc_init_tfm(struct crypto_tfm *tfm) { struct crypto_cipher *cipher; struct crypto_instance *inst = (void *)tfm->__crt_alg; struct crypto_cipher_spawn *spawn = crypto_instance_ctx(inst); struct xcbc_tfm_ctx *ctx = crypto_tfm_ctx(tfm); cipher = crypto_spawn_cipher(spawn); if (IS_ERR(cipher)) return PTR_ERR(cipher); ctx->child = cipher; return 0; }; static void xcbc_exit_tfm(struct crypto_tfm *tfm) { struct xcbc_tfm_ctx *ctx = crypto_tfm_ctx(tfm); crypto_free_cipher(ctx->child); } static int xcbc_create(struct crypto_template *tmpl, struct rtattr **tb) { struct shash_instance *inst; struct crypto_cipher_spawn *spawn; struct crypto_alg *alg; u32 mask; int err; err = crypto_check_attr_type(tb, CRYPTO_ALG_TYPE_SHASH, &mask); if (err) return err; inst = kzalloc(sizeof(*inst) + sizeof(*spawn), GFP_KERNEL); if (!inst) return -ENOMEM; spawn = shash_instance_ctx(inst); err = crypto_grab_cipher(spawn, shash_crypto_instance(inst), crypto_attr_alg_name(tb[1]), 0, mask); if (err) goto err_free_inst; alg = crypto_spawn_cipher_alg(spawn); err = -EINVAL; if (alg->cra_blocksize != XCBC_BLOCKSIZE) goto err_free_inst; err = crypto_inst_setname(shash_crypto_instance(inst), tmpl->name, alg); if (err) goto err_free_inst; inst->alg.base.cra_priority = alg->cra_priority; inst->alg.base.cra_blocksize = alg->cra_blocksize; inst->alg.base.cra_ctxsize = sizeof(struct xcbc_tfm_ctx) + alg->cra_blocksize * 2; inst->alg.digestsize = alg->cra_blocksize; inst->alg.descsize = sizeof(struct xcbc_desc_ctx) + alg->cra_blocksize * 2; inst->alg.base.cra_init = xcbc_init_tfm; inst->alg.base.cra_exit = xcbc_exit_tfm; inst->alg.init = crypto_xcbc_digest_init; inst->alg.update = crypto_xcbc_digest_update; inst->alg.final = crypto_xcbc_digest_final; inst->alg.setkey = crypto_xcbc_digest_setkey; inst->free = shash_free_singlespawn_instance; err = shash_register_instance(tmpl, inst); if (err) { err_free_inst: shash_free_singlespawn_instance(inst); } return err; } static struct crypto_template crypto_xcbc_tmpl = { .name = "xcbc", .create = xcbc_create, .module = THIS_MODULE, }; static int __init crypto_xcbc_module_init(void) { return crypto_register_template(&crypto_xcbc_tmpl); } static void __exit crypto_xcbc_module_exit(void) { crypto_unregister_template(&crypto_xcbc_tmpl); } subsys_initcall(crypto_xcbc_module_init); module_exit(crypto_xcbc_module_exit); MODULE_LICENSE("GPL"); MODULE_DESCRIPTION("XCBC keyed hash algorithm"); MODULE_ALIAS_CRYPTO("xcbc"); MODULE_IMPORT_NS(CRYPTO_INTERNAL);