Orange Pi5 kernel

// SPDX-License-Identifier: GPL-2.0-or-later
/*
 * Cryptographic API.
 *
 * HMAC: Keyed-Hashing for Message Authentication (RFC2104).
 *
 * Copyright (c) 2002 James Morris <jmorris@intercode.com.au>
 * Copyright (c) 2006 Herbert Xu <herbert@gondor.apana.org.au>
 *
 * The HMAC implementation is derived from USAGI.
 * Copyright (c) 2002 Kazunori Miyazawa <miyazawa@linux-ipv6.org> / USAGI
 */
 
#include <crypto/hmac.h>
#include <crypto/internal/hash.h>
#include <crypto/scatterwalk.h>
#include <linux/err.h>
#include <linux/init.h>
#include <linux/kernel.h>
#include <linux/module.h>
#include <linux/scatterlist.h>
#include <linux/string.h>
 
struct hmac_ctx {
<------>struct crypto_shash *hash;
};
 
static inline void *align_ptr(void *p, unsigned int align)
{
<------>return (void *)ALIGN((unsigned long)p, align);
}
 
static inline struct hmac_ctx *hmac_ctx(struct crypto_shash *tfm)
{
<------>return align_ptr(crypto_shash_ctx_aligned(tfm) +
<------><------><------> crypto_shash_statesize(tfm) * 2,
<------><------><------> crypto_tfm_ctx_alignment());
}
 
static int hmac_setkey(struct crypto_shash *parent,
<------><------>       const u8 *inkey, unsigned int keylen)
{
<------>int bs = crypto_shash_blocksize(parent);
<------>int ds = crypto_shash_digestsize(parent);
<------>int ss = crypto_shash_statesize(parent);
<------>char *ipad = crypto_shash_ctx_aligned(parent);
<------>char *opad = ipad + ss;
<------>struct hmac_ctx *ctx = align_ptr(opad + ss,
<------><------><------><------><------> crypto_tfm_ctx_alignment());
<------>struct crypto_shash *hash = ctx->hash;
<------>SHASH_DESC_ON_STACK(shash, hash);
<------>unsigned int i;
 
<------>shash->tfm = hash;
 
<------>if (keylen > bs) {
<------><------>int err;
 
<------><------>err = crypto_shash_digest(shash, inkey, keylen, ipad);
<------><------>if (err)
<------><------><------>return err;
 
<------><------>keylen = ds;
<------>} else
<------><------>memcpy(ipad, inkey, keylen);
 
<------>memset(ipad + keylen, 0, bs - keylen);
<------>memcpy(opad, ipad, bs);
 
<------>for (i = 0; i < bs; i++) {
<------><------>ipad[i] ^= HMAC_IPAD_VALUE;
<------><------>opad[i] ^= HMAC_OPAD_VALUE;
<------>}
 
<------>return crypto_shash_init(shash) ?:
<------>       crypto_shash_update(shash, ipad, bs) ?:
<------>       crypto_shash_export(shash, ipad) ?:
<------>       crypto_shash_init(shash) ?:
<------>       crypto_shash_update(shash, opad, bs) ?:
<------>       crypto_shash_export(shash, opad);
}
 
static int hmac_export(struct shash_desc *pdesc, void *out)
{
<------>struct shash_desc *desc = shash_desc_ctx(pdesc);
 
<------>return crypto_shash_export(desc, out);
}
 
static int hmac_import(struct shash_desc *pdesc, const void *in)
{
<------>struct shash_desc *desc = shash_desc_ctx(pdesc);
<------>struct hmac_ctx *ctx = hmac_ctx(pdesc->tfm);
 
<------>desc->tfm = ctx->hash;
 
<------>return crypto_shash_import(desc, in);
}
 
static int hmac_init(struct shash_desc *pdesc)
{
<------>return hmac_import(pdesc, crypto_shash_ctx_aligned(pdesc->tfm));
}
 
static int hmac_update(struct shash_desc *pdesc,
<------><------>       const u8 *data, unsigned int nbytes)
{
<------>struct shash_desc *desc = shash_desc_ctx(pdesc);
 
<------>return crypto_shash_update(desc, data, nbytes);
}
 
static int hmac_final(struct shash_desc *pdesc, u8 *out)
{
<------>struct crypto_shash *parent = pdesc->tfm;
<------>int ds = crypto_shash_digestsize(parent);
<------>int ss = crypto_shash_statesize(parent);
<------>char *opad = crypto_shash_ctx_aligned(parent) + ss;
<------>struct shash_desc *desc = shash_desc_ctx(pdesc);
 
<------>return crypto_shash_final(desc, out) ?:
<------>       crypto_shash_import(desc, opad) ?:
<------>       crypto_shash_finup(desc, out, ds, out);
}
 
static int hmac_finup(struct shash_desc *pdesc, const u8 *data,
<------><------>      unsigned int nbytes, u8 *out)
{
 
<------>struct crypto_shash *parent = pdesc->tfm;
<------>int ds = crypto_shash_digestsize(parent);
<------>int ss = crypto_shash_statesize(parent);
<------>char *opad = crypto_shash_ctx_aligned(parent) + ss;
<------>struct shash_desc *desc = shash_desc_ctx(pdesc);
 
<------>return crypto_shash_finup(desc, data, nbytes, out) ?:
<------>       crypto_shash_import(desc, opad) ?:
<------>       crypto_shash_finup(desc, out, ds, out);
}
 
static int hmac_init_tfm(struct crypto_shash *parent)
{
<------>struct crypto_shash *hash;
<------>struct shash_instance *inst = shash_alg_instance(parent);
<------>struct crypto_shash_spawn *spawn = shash_instance_ctx(inst);
<------>struct hmac_ctx *ctx = hmac_ctx(parent);
 
<------>hash = crypto_spawn_shash(spawn);
<------>if (IS_ERR(hash))
<------><------>return PTR_ERR(hash);
 
<------>parent->descsize = sizeof(struct shash_desc) +
<------><------><------>   crypto_shash_descsize(hash);
 
<------>ctx->hash = hash;
<------>return 0;
}
 
static void hmac_exit_tfm(struct crypto_shash *parent)
{
<------>struct hmac_ctx *ctx = hmac_ctx(parent);
<------>crypto_free_shash(ctx->hash);
}
 
static int hmac_create(struct crypto_template *tmpl, struct rtattr **tb)
{
<------>struct shash_instance *inst;
<------>struct crypto_shash_spawn *spawn;
<------>struct crypto_alg *alg;
<------>struct shash_alg *salg;
<------>u32 mask;
<------>int err;
<------>int ds;
<------>int ss;
 
<------>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_shash(spawn, shash_crypto_instance(inst),
<------><------><------><------>crypto_attr_alg_name(tb[1]), 0, mask);
<------>if (err)
<------><------>goto err_free_inst;
<------>salg = crypto_spawn_shash_alg(spawn);
<------>alg = &salg->base;
 
<------>/* The underlying hash algorithm must not require a key */
<------>err = -EINVAL;
<------>if (crypto_shash_alg_needs_key(salg))
<------><------>goto err_free_inst;
 
<------>ds = salg->digestsize;
<------>ss = salg->statesize;
<------>if (ds > alg->cra_blocksize ||
<------>    ss < alg->cra_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_alignmask = alg->cra_alignmask;
 
<------>ss = ALIGN(ss, alg->cra_alignmask + 1);
<------>inst->alg.digestsize = ds;
<------>inst->alg.statesize = ss;
 
<------>inst->alg.base.cra_ctxsize = sizeof(struct hmac_ctx) +
<------><------><------><------>     ALIGN(ss * 2, crypto_tfm_ctx_alignment());
 
<------>inst->alg.init = hmac_init;
<------>inst->alg.update = hmac_update;
<------>inst->alg.final = hmac_final;
<------>inst->alg.finup = hmac_finup;
<------>inst->alg.export = hmac_export;
<------>inst->alg.import = hmac_import;
<------>inst->alg.setkey = hmac_setkey;
<------>inst->alg.init_tfm = hmac_init_tfm;
<------>inst->alg.exit_tfm = hmac_exit_tfm;
 
<------>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 hmac_tmpl = {
<------>.name = "hmac",
<------>.create = hmac_create,
<------>.module = THIS_MODULE,
};
 
static int __init hmac_module_init(void)
{
<------>return crypto_register_template(&hmac_tmpl);
}
 
static void __exit hmac_module_exit(void)
{
<------>crypto_unregister_template(&hmac_tmpl);
}
 
subsys_initcall(hmac_module_init);
module_exit(hmac_module_exit);
 
MODULE_LICENSE("GPL");
MODULE_DESCRIPTION("HMAC hash algorithm");
MODULE_ALIAS_CRYPTO("hmac");