Commit c4e961ec authored by AKASHI Takahiro's avatar AKASHI Takahiro Committed by Tom Rini

lib: crypto: add public key utility

Imported from linux kernel v5.3:
 asymmetric-type.h with changes marked as __UBOOT__
 asymmetric_type.c with changes marked as __UBOOT__
 public_key.h with changes marked as __UBOOT__
 public_key.c with changes marked as __UBOOT__
Signed-off-by: default avatarAKASHI Takahiro <takahiro.akashi@linaro.org>
parent a9b45e6e
/* SPDX-License-Identifier: GPL-2.0-or-later */
/* Asymmetric public-key algorithm definitions
*
* See Documentation/crypto/asymmetric-keys.txt
*
* Copyright (C) 2012 Red Hat, Inc. All Rights Reserved.
* Written by David Howells (dhowells@redhat.com)
*/
#ifndef _LINUX_PUBLIC_KEY_H
#define _LINUX_PUBLIC_KEY_H
#ifdef __UBOOT__
#include <linux/types.h>
#else
#include <linux/keyctl.h>
#endif
#include <linux/oid_registry.h>
/*
* Cryptographic data for the public-key subtype of the asymmetric key type.
*
* Note that this may include private part of the key as well as the public
* part.
*/
struct public_key {
void *key;
u32 keylen;
enum OID algo;
void *params;
u32 paramlen;
bool key_is_private;
const char *id_type;
const char *pkey_algo;
};
extern void public_key_free(struct public_key *key);
/*
* Public key cryptography signature data
*/
struct public_key_signature {
struct asymmetric_key_id *auth_ids[2];
u8 *s; /* Signature */
u32 s_size; /* Number of bytes in signature */
u8 *digest;
u8 digest_size; /* Number of bytes in digest */
const char *pkey_algo;
const char *hash_algo;
const char *encoding;
};
extern void public_key_signature_free(struct public_key_signature *sig);
#ifndef __UBOOT__
extern struct asymmetric_key_subtype public_key_subtype;
struct key;
struct key_type;
union key_payload;
extern int restrict_link_by_signature(struct key *dest_keyring,
const struct key_type *type,
const union key_payload *payload,
struct key *trust_keyring);
extern int restrict_link_by_key_or_keyring(struct key *dest_keyring,
const struct key_type *type,
const union key_payload *payload,
struct key *trusted);
extern int restrict_link_by_key_or_keyring_chain(struct key *trust_keyring,
const struct key_type *type,
const union key_payload *payload,
struct key *trusted);
extern int query_asymmetric_key(const struct kernel_pkey_params *,
struct kernel_pkey_query *);
extern int encrypt_blob(struct kernel_pkey_params *, const void *, void *);
extern int decrypt_blob(struct kernel_pkey_params *, const void *, void *);
extern int create_signature(struct kernel_pkey_params *, const void *, void *);
extern int verify_signature(const struct key *,
const struct public_key_signature *);
int public_key_verify_signature(const struct public_key *pkey,
const struct public_key_signature *sig);
#endif /* !__UBOOT__ */
#endif /* _LINUX_PUBLIC_KEY_H */
/* SPDX-License-Identifier: GPL-2.0-or-later */
/* Asymmetric Public-key cryptography key type interface
*
* See Documentation/crypto/asymmetric-keys.txt
*
* Copyright (C) 2012 Red Hat, Inc. All Rights Reserved.
* Written by David Howells (dhowells@redhat.com)
*/
#ifndef _KEYS_ASYMMETRIC_TYPE_H
#define _KEYS_ASYMMETRIC_TYPE_H
#ifndef __UBOOT__
#include <linux/key-type.h>
#include <linux/verification.h>
extern struct key_type key_type_asymmetric;
/*
* The key payload is four words. The asymmetric-type key uses them as
* follows:
*/
enum asymmetric_payload_bits {
asym_crypto, /* The data representing the key */
asym_subtype, /* Pointer to an asymmetric_key_subtype struct */
asym_key_ids, /* Pointer to an asymmetric_key_ids struct */
asym_auth /* The key's authorisation (signature, parent key ID) */
};
#endif /* !__UBOOT__ */
/*
* Identifiers for an asymmetric key ID. We have three ways of looking up a
* key derived from an X.509 certificate:
*
* (1) Serial Number & Issuer. Non-optional. This is the only valid way to
* map a PKCS#7 signature to an X.509 certificate.
*
* (2) Issuer & Subject Unique IDs. Optional. These were the original way to
* match X.509 certificates, but have fallen into disuse in favour of (3).
*
* (3) Auth & Subject Key Identifiers. Optional. SKIDs are only provided on
* CA keys that are intended to sign other keys, so don't appear in end
* user certificates unless forced.
*
* We could also support an PGP key identifier, which is just a SHA1 sum of the
* public key and certain parameters, but since we don't support PGP keys at
* the moment, we shall ignore those.
*
* What we actually do is provide a place where binary identifiers can be
* stashed and then compare against them when checking for an id match.
*/
struct asymmetric_key_id {
unsigned short len;
unsigned char data[];
};
struct asymmetric_key_ids {
void *id[2];
};
extern bool asymmetric_key_id_same(const struct asymmetric_key_id *kid1,
const struct asymmetric_key_id *kid2);
extern bool asymmetric_key_id_partial(const struct asymmetric_key_id *kid1,
const struct asymmetric_key_id *kid2);
extern struct asymmetric_key_id *asymmetric_key_generate_id(const void *val_1,
size_t len_1,
const void *val_2,
size_t len_2);
#ifndef __UBOOT__
static inline
const struct asymmetric_key_ids *asymmetric_key_ids(const struct key *key)
{
return key->payload.data[asym_key_ids];
}
extern struct key *find_asymmetric_key(struct key *keyring,
const struct asymmetric_key_id *id_0,
const struct asymmetric_key_id *id_1,
bool partial);
#endif
/*
* The payload is at the discretion of the subtype.
*/
#endif /* _KEYS_ASYMMETRIC_TYPE_H */
menuconfig ASYMMETRIC_KEY_TYPE
bool "Asymmetric (public-key cryptographic) key Support"
help
This option provides support for a key type that holds the data for
the asymmetric keys used for public key cryptographic operations such
as encryption, decryption, signature generation and signature
verification.
if ASYMMETRIC_KEY_TYPE
config ASYMMETRIC_PUBLIC_KEY_SUBTYPE
bool "Asymmetric public-key crypto algorithm subtype"
help
This option provides support for asymmetric public key type handling.
If signature generation and/or verification are to be used,
appropriate hash algorithms (such as SHA-1) must be available.
ENOPKG will be reported if the requisite algorithm is unavailable.
endif # ASYMMETRIC_KEY_TYPE
# SPDX-License-Identifier: GPL-2.0+
#
# Makefile for asymmetric cryptographic keys
#
obj-$(CONFIG_ASYMMETRIC_KEY_TYPE) += asymmetric_keys.o
asymmetric_keys-y := asymmetric_type.o
obj-$(CONFIG_ASYMMETRIC_PUBLIC_KEY_SUBTYPE) += public_key.o
This diff is collapsed.
// SPDX-License-Identifier: GPL-2.0-or-later
/* In-software asymmetric public-key crypto subtype
*
* See Documentation/crypto/asymmetric-keys.txt
*
* Copyright (C) 2012 Red Hat, Inc. All Rights Reserved.
* Written by David Howells (dhowells@redhat.com)
*/
#define pr_fmt(fmt) "PKEY: "fmt
#ifdef __UBOOT__
#include <linux/compat.h>
#else
#include <linux/module.h>
#include <linux/export.h>
#endif
#include <linux/kernel.h>
#ifndef __UBOOT__
#include <linux/slab.h>
#include <linux/seq_file.h>
#include <linux/scatterlist.h>
#include <keys/asymmetric-subtype.h>
#endif
#include <crypto/public_key.h>
#ifndef __UBOOT__
#include <crypto/akcipher.h>
#endif
MODULE_DESCRIPTION("In-software asymmetric public-key subtype");
MODULE_AUTHOR("Red Hat, Inc.");
MODULE_LICENSE("GPL");
#ifndef __UBOOT__
/*
* Provide a part of a description of the key for /proc/keys.
*/
static void public_key_describe(const struct key *asymmetric_key,
struct seq_file *m)
{
struct public_key *key = asymmetric_key->payload.data[asym_crypto];
if (key)
seq_printf(m, "%s.%s", key->id_type, key->pkey_algo);
}
#endif
/*
* Destroy a public key algorithm key.
*/
void public_key_free(struct public_key *key)
{
if (key) {
kfree(key->key);
kfree(key->params);
kfree(key);
}
}
EXPORT_SYMBOL_GPL(public_key_free);
#ifdef __UBOOT__
/*
* from <linux>/crypto/asymmetric_keys/signature.c
*
* Destroy a public key signature.
*/
void public_key_signature_free(struct public_key_signature *sig)
{
int i;
if (sig) {
for (i = 0; i < ARRAY_SIZE(sig->auth_ids); i++)
free(sig->auth_ids[i]);
free(sig->s);
free(sig->digest);
free(sig);
}
}
EXPORT_SYMBOL_GPL(public_key_signature_free);
#else
/*
* Destroy a public key algorithm key.
*/
static void public_key_destroy(void *payload0, void *payload3)
{
public_key_free(payload0);
public_key_signature_free(payload3);
}
/*
* Determine the crypto algorithm name.
*/
static
int software_key_determine_akcipher(const char *encoding,
const char *hash_algo,
const struct public_key *pkey,
char alg_name[CRYPTO_MAX_ALG_NAME])
{
int n;
if (strcmp(encoding, "pkcs1") == 0) {
/* The data wangled by the RSA algorithm is typically padded
* and encoded in some manner, such as EMSA-PKCS1-1_5 [RFC3447
* sec 8.2].
*/
if (!hash_algo)
n = snprintf(alg_name, CRYPTO_MAX_ALG_NAME,
"pkcs1pad(%s)",
pkey->pkey_algo);
else
n = snprintf(alg_name, CRYPTO_MAX_ALG_NAME,
"pkcs1pad(%s,%s)",
pkey->pkey_algo, hash_algo);
return n >= CRYPTO_MAX_ALG_NAME ? -EINVAL : 0;
}
if (strcmp(encoding, "raw") == 0) {
strcpy(alg_name, pkey->pkey_algo);
return 0;
}
return -ENOPKG;
}
static u8 *pkey_pack_u32(u8 *dst, u32 val)
{
memcpy(dst, &val, sizeof(val));
return dst + sizeof(val);
}
/*
* Query information about a key.
*/
static int software_key_query(const struct kernel_pkey_params *params,
struct kernel_pkey_query *info)
{
struct crypto_akcipher *tfm;
struct public_key *pkey = params->key->payload.data[asym_crypto];
char alg_name[CRYPTO_MAX_ALG_NAME];
u8 *key, *ptr;
int ret, len;
ret = software_key_determine_akcipher(params->encoding,
params->hash_algo,
pkey, alg_name);
if (ret < 0)
return ret;
tfm = crypto_alloc_akcipher(alg_name, 0, 0);
if (IS_ERR(tfm))
return PTR_ERR(tfm);
key = kmalloc(pkey->keylen + sizeof(u32) * 2 + pkey->paramlen,
GFP_KERNEL);
if (!key)
goto error_free_tfm;
memcpy(key, pkey->key, pkey->keylen);
ptr = key + pkey->keylen;
ptr = pkey_pack_u32(ptr, pkey->algo);
ptr = pkey_pack_u32(ptr, pkey->paramlen);
memcpy(ptr, pkey->params, pkey->paramlen);
if (pkey->key_is_private)
ret = crypto_akcipher_set_priv_key(tfm, key, pkey->keylen);
else
ret = crypto_akcipher_set_pub_key(tfm, key, pkey->keylen);
if (ret < 0)
goto error_free_key;
len = crypto_akcipher_maxsize(tfm);
info->key_size = len * 8;
info->max_data_size = len;
info->max_sig_size = len;
info->max_enc_size = len;
info->max_dec_size = len;
info->supported_ops = (KEYCTL_SUPPORTS_ENCRYPT |
KEYCTL_SUPPORTS_VERIFY);
if (pkey->key_is_private)
info->supported_ops |= (KEYCTL_SUPPORTS_DECRYPT |
KEYCTL_SUPPORTS_SIGN);
ret = 0;
error_free_key:
kfree(key);
error_free_tfm:
crypto_free_akcipher(tfm);
pr_devel("<==%s() = %d\n", __func__, ret);
return ret;
}
/*
* Do encryption, decryption and signing ops.
*/
static int software_key_eds_op(struct kernel_pkey_params *params,
const void *in, void *out)
{
const struct public_key *pkey = params->key->payload.data[asym_crypto];
struct akcipher_request *req;
struct crypto_akcipher *tfm;
struct crypto_wait cwait;
struct scatterlist in_sg, out_sg;
char alg_name[CRYPTO_MAX_ALG_NAME];
char *key, *ptr;
int ret;
pr_devel("==>%s()\n", __func__);
ret = software_key_determine_akcipher(params->encoding,
params->hash_algo,
pkey, alg_name);
if (ret < 0)
return ret;
tfm = crypto_alloc_akcipher(alg_name, 0, 0);
if (IS_ERR(tfm))
return PTR_ERR(tfm);
req = akcipher_request_alloc(tfm, GFP_KERNEL);
if (!req)
goto error_free_tfm;
key = kmalloc(pkey->keylen + sizeof(u32) * 2 + pkey->paramlen,
GFP_KERNEL);
if (!key)
goto error_free_req;
memcpy(key, pkey->key, pkey->keylen);
ptr = key + pkey->keylen;
ptr = pkey_pack_u32(ptr, pkey->algo);
ptr = pkey_pack_u32(ptr, pkey->paramlen);
memcpy(ptr, pkey->params, pkey->paramlen);
if (pkey->key_is_private)
ret = crypto_akcipher_set_priv_key(tfm, key, pkey->keylen);
else
ret = crypto_akcipher_set_pub_key(tfm, key, pkey->keylen);
if (ret)
goto error_free_key;
sg_init_one(&in_sg, in, params->in_len);
sg_init_one(&out_sg, out, params->out_len);
akcipher_request_set_crypt(req, &in_sg, &out_sg, params->in_len,
params->out_len);
crypto_init_wait(&cwait);
akcipher_request_set_callback(req, CRYPTO_TFM_REQ_MAY_BACKLOG |
CRYPTO_TFM_REQ_MAY_SLEEP,
crypto_req_done, &cwait);
/* Perform the encryption calculation. */
switch (params->op) {
case kernel_pkey_encrypt:
ret = crypto_akcipher_encrypt(req);
break;
case kernel_pkey_decrypt:
ret = crypto_akcipher_decrypt(req);
break;
case kernel_pkey_sign:
ret = crypto_akcipher_sign(req);
break;
default:
BUG();
}
ret = crypto_wait_req(ret, &cwait);
if (ret == 0)
ret = req->dst_len;
error_free_key:
kfree(key);
error_free_req:
akcipher_request_free(req);
error_free_tfm:
crypto_free_akcipher(tfm);
pr_devel("<==%s() = %d\n", __func__, ret);
return ret;
}
/*
* Verify a signature using a public key.
*/
int public_key_verify_signature(const struct public_key *pkey,
const struct public_key_signature *sig)
{
struct crypto_wait cwait;
struct crypto_akcipher *tfm;
struct akcipher_request *req;
struct scatterlist src_sg[2];
char alg_name[CRYPTO_MAX_ALG_NAME];
char *key, *ptr;
int ret;
pr_devel("==>%s()\n", __func__);
BUG_ON(!pkey);
BUG_ON(!sig);
BUG_ON(!sig->s);
ret = software_key_determine_akcipher(sig->encoding,
sig->hash_algo,
pkey, alg_name);
if (ret < 0)
return ret;
tfm = crypto_alloc_akcipher(alg_name, 0, 0);
if (IS_ERR(tfm))
return PTR_ERR(tfm);
ret = -ENOMEM;
req = akcipher_request_alloc(tfm, GFP_KERNEL);
if (!req)
goto error_free_tfm;
key = kmalloc(pkey->keylen + sizeof(u32) * 2 + pkey->paramlen,
GFP_KERNEL);
if (!key)
goto error_free_req;
memcpy(key, pkey->key, pkey->keylen);
ptr = key + pkey->keylen;
ptr = pkey_pack_u32(ptr, pkey->algo);
ptr = pkey_pack_u32(ptr, pkey->paramlen);
memcpy(ptr, pkey->params, pkey->paramlen);
if (pkey->key_is_private)
ret = crypto_akcipher_set_priv_key(tfm, key, pkey->keylen);
else
ret = crypto_akcipher_set_pub_key(tfm, key, pkey->keylen);
if (ret)
goto error_free_key;
sg_init_table(src_sg, 2);
sg_set_buf(&src_sg[0], sig->s, sig->s_size);
sg_set_buf(&src_sg[1], sig->digest, sig->digest_size);
akcipher_request_set_crypt(req, src_sg, NULL, sig->s_size,
sig->digest_size);
crypto_init_wait(&cwait);
akcipher_request_set_callback(req, CRYPTO_TFM_REQ_MAY_BACKLOG |
CRYPTO_TFM_REQ_MAY_SLEEP,
crypto_req_done, &cwait);
ret = crypto_wait_req(crypto_akcipher_verify(req), &cwait);
error_free_key:
kfree(key);
error_free_req:
akcipher_request_free(req);
error_free_tfm:
crypto_free_akcipher(tfm);
pr_devel("<==%s() = %d\n", __func__, ret);
if (WARN_ON_ONCE(ret > 0))
ret = -EINVAL;
return ret;
}
EXPORT_SYMBOL_GPL(public_key_verify_signature);
static int public_key_verify_signature_2(const struct key *key,
const struct public_key_signature *sig)
{
const struct public_key *pk = key->payload.data[asym_crypto];
return public_key_verify_signature(pk, sig);
}
/*
* Public key algorithm asymmetric key subtype
*/
struct asymmetric_key_subtype public_key_subtype = {
.owner = THIS_MODULE,
.name = "public_key",
.name_len = sizeof("public_key") - 1,
.describe = public_key_describe,
.destroy = public_key_destroy,
.query = software_key_query,
.eds_op = software_key_eds_op,
.verify_signature = public_key_verify_signature_2,
};
EXPORT_SYMBOL_GPL(public_key_subtype);
#endif /* !__UBOOT__ */
Markdown is supported
0%
or
You are about to add 0 people to the discussion. Proceed with caution.
Finish editing this message first!
Please register or to comment