tjh.dev
Linux kernel mirror (for testing)
git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git
kernel
os
linux
crypto/krb5: Implement Kerberos crypto core
Provide core structures, an encoding-type registry and basic module and
config bits for a generic Kerberos crypto library.
Signed-off-by: David Howells <dhowells@redhat.com>
cc: Herbert Xu <herbert@gondor.apana.org.au>
cc: "David S. Miller" <davem@davemloft.net>
cc: Chuck Lever <chuck.lever@oracle.com>
cc: Marc Dionne <marc.dionne@auristor.com>
cc: Eric Dumazet <edumazet@google.com>
cc: Jakub Kicinski <kuba@kernel.org>
cc: Paolo Abeni <pabeni@redhat.com>
cc: Simon Horman <horms@kernel.org>
cc: linux-afs@lists.infradead.org
cc: linux-nfs@vger.kernel.org
cc: linux-crypto@vger.kernel.org
cc: netdev@vger.kernel.org
+234
+1
crypto/Kconfig
+1
crypto/Kconfig
+2
crypto/Makefile
+2
crypto/Makefile
+14
crypto/krb5/Kconfig
+14
crypto/krb5/Kconfig
···
1
+
config CRYPTO_KRB5
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tristate "Kerberos 5 crypto"
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select CRYPTO_MANAGER
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select CRYPTO_KRB5ENC
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select CRYPTO_AUTHENC
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select CRYPTO_SKCIPHER
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select CRYPTO_HASH_INFO
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select CRYPTO_SHA1
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select CRYPTO_CBC
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select CRYPTO_CTS
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select CRYPTO_AES
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help
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Provide a library for provision of Kerberos-5-based crypto. This is
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intended for network filesystems to use.
+9
crypto/krb5/Makefile
+9
crypto/krb5/Makefile
+112
crypto/krb5/internal.h
+112
crypto/krb5/internal.h
···
1
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/* SPDX-License-Identifier: GPL-2.0-or-later */
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/* Kerberos5 crypto internals
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*
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* Copyright (C) 2025 Red Hat, Inc. All Rights Reserved.
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* Written by David Howells (dhowells@redhat.com)
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*/
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+
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#include <crypto/krb5.h>
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/*
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* Profile used for key derivation and encryption.
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*/
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struct krb5_crypto_profile {
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/* Pseudo-random function */
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int (*calc_PRF)(const struct krb5_enctype *krb5,
16
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const struct krb5_buffer *protocol_key,
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const struct krb5_buffer *octet_string,
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struct krb5_buffer *result,
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gfp_t gfp);
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+
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/* Checksum key derivation */
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int (*calc_Kc)(const struct krb5_enctype *krb5,
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const struct krb5_buffer *TK,
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const struct krb5_buffer *usage_constant,
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struct krb5_buffer *Kc,
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gfp_t gfp);
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+
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/* Encryption key derivation */
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int (*calc_Ke)(const struct krb5_enctype *krb5,
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const struct krb5_buffer *TK,
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const struct krb5_buffer *usage_constant,
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struct krb5_buffer *Ke,
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gfp_t gfp);
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+
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/* Integrity key derivation */
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int (*calc_Ki)(const struct krb5_enctype *krb5,
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const struct krb5_buffer *TK,
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const struct krb5_buffer *usage_constant,
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struct krb5_buffer *Ki,
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gfp_t gfp);
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+
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/* Derive the keys needed for an encryption AEAD object. */
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int (*derive_encrypt_keys)(const struct krb5_enctype *krb5,
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const struct krb5_buffer *TK,
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unsigned int usage,
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struct krb5_buffer *setkey,
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gfp_t gfp);
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+
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/* Directly load the keys needed for an encryption AEAD object. */
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int (*load_encrypt_keys)(const struct krb5_enctype *krb5,
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const struct krb5_buffer *Ke,
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const struct krb5_buffer *Ki,
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struct krb5_buffer *setkey,
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gfp_t gfp);
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/* Derive the key needed for a checksum hash object. */
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int (*derive_checksum_key)(const struct krb5_enctype *krb5,
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const struct krb5_buffer *TK,
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unsigned int usage,
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struct krb5_buffer *setkey,
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gfp_t gfp);
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/* Directly load the keys needed for a checksum hash object. */
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int (*load_checksum_key)(const struct krb5_enctype *krb5,
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const struct krb5_buffer *Kc,
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struct krb5_buffer *setkey,
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gfp_t gfp);
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+
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/* Encrypt data in-place, inserting confounder and checksum. */
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ssize_t (*encrypt)(const struct krb5_enctype *krb5,
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struct crypto_aead *aead,
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struct scatterlist *sg, unsigned int nr_sg,
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size_t sg_len,
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size_t data_offset, size_t data_len,
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bool preconfounded);
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+
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/* Decrypt data in-place, removing confounder and checksum */
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int (*decrypt)(const struct krb5_enctype *krb5,
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struct crypto_aead *aead,
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struct scatterlist *sg, unsigned int nr_sg,
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size_t *_offset, size_t *_len);
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/* Generate a MIC on part of a packet, inserting the checksum */
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ssize_t (*get_mic)(const struct krb5_enctype *krb5,
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struct crypto_shash *shash,
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const struct krb5_buffer *metadata,
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struct scatterlist *sg, unsigned int nr_sg,
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size_t sg_len,
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size_t data_offset, size_t data_len);
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/* Verify the MIC on a piece of data, removing the checksum */
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int (*verify_mic)(const struct krb5_enctype *krb5,
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struct crypto_shash *shash,
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const struct krb5_buffer *metadata,
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struct scatterlist *sg, unsigned int nr_sg,
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size_t *_offset, size_t *_len);
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};
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/*
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* Crypto size/alignment rounding convenience macros.
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*/
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#define crypto_roundup(X) ((unsigned int)round_up((X), CRYPTO_MINALIGN))
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#define krb5_aead_size(TFM) \
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crypto_roundup(sizeof(struct aead_request) + crypto_aead_reqsize(TFM))
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#define krb5_aead_ivsize(TFM) \
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crypto_roundup(crypto_aead_ivsize(TFM))
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#define krb5_shash_size(TFM) \
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crypto_roundup(sizeof(struct shash_desc) + crypto_shash_descsize(TFM))
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#define krb5_digest_size(TFM) \
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crypto_roundup(crypto_shash_digestsize(TFM))
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#define round16(x) (((x) + 15) & ~15)
+42
crypto/krb5/krb5_api.c
+42
crypto/krb5/krb5_api.c
···
1
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// SPDX-License-Identifier: GPL-2.0-or-later
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/* Kerberos 5 crypto library.
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*
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* Copyright (C) 2025 Red Hat, Inc. All Rights Reserved.
5
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* Written by David Howells (dhowells@redhat.com)
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*/
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#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
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#include <linux/module.h>
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#include <linux/export.h>
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#include <linux/kernel.h>
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#include "internal.h"
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MODULE_DESCRIPTION("Kerberos 5 crypto");
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MODULE_AUTHOR("Red Hat, Inc.");
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MODULE_LICENSE("GPL");
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static const struct krb5_enctype *const krb5_supported_enctypes[] = {
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};
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/**
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* crypto_krb5_find_enctype - Find the handler for a Kerberos5 encryption type
24
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* @enctype: The standard Kerberos encryption type number
25
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*
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* Look up a Kerberos encryption type by number. If successful, returns a
27
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* pointer to the type tables; returns NULL otherwise.
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*/
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const struct krb5_enctype *crypto_krb5_find_enctype(u32 enctype)
30
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{
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const struct krb5_enctype *krb5;
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size_t i;
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for (i = 0; i < ARRAY_SIZE(krb5_supported_enctypes); i++) {
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krb5 = krb5_supported_enctypes[i];
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if (krb5->etype == enctype)
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return krb5;
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}
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return NULL;
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}
42
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EXPORT_SYMBOL(crypto_krb5_find_enctype);
+54
include/crypto/krb5.h
+54
include/crypto/krb5.h
···
8
8
#ifndef _CRYPTO_KRB5_H
9
9
#define _CRYPTO_KRB5_H
10
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#include <linux/crypto.h>
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#include <crypto/aead.h>
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struct crypto_shash;
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struct scatterlist;
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+
11
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/*
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* Per Kerberos v5 protocol spec crypto types from the wire. These get mapped
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* to linux kernel crypto routines.
···
53
47
#define KEY_USAGE_SEED_CHECKSUM (0x99)
54
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#define KEY_USAGE_SEED_ENCRYPTION (0xAA)
55
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#define KEY_USAGE_SEED_INTEGRITY (0x55)
50
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51
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/*
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* Mode of operation.
53
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*/
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enum krb5_crypto_mode {
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KRB5_CHECKSUM_MODE, /* Checksum only */
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KRB5_ENCRYPT_MODE, /* Fully encrypted, possibly with integrity checksum */
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};
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+
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struct krb5_buffer {
60
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unsigned int len;
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void *data;
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};
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+
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/*
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* Kerberos encoding type definition.
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*/
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struct krb5_enctype {
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int etype; /* Encryption (key) type */
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int ctype; /* Checksum type */
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const char *name; /* "Friendly" name */
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const char *encrypt_name; /* Crypto encrypt+checksum name */
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const char *cksum_name; /* Crypto checksum name */
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const char *hash_name; /* Crypto hash name */
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const char *derivation_enc; /* Cipher used in key derivation */
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u16 block_len; /* Length of encryption block */
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u16 conf_len; /* Length of confounder (normally == block_len) */
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u16 cksum_len; /* Length of checksum */
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u16 key_bytes; /* Length of raw key, in bytes */
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u16 key_len; /* Length of final key, in bytes */
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u16 hash_len; /* Length of hash in bytes */
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u16 prf_len; /* Length of PRF() result in bytes */
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u16 Kc_len; /* Length of Kc in bytes */
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u16 Ke_len; /* Length of Ke in bytes */
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+
u16 Ki_len; /* Length of Ki in bytes */
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bool keyed_cksum; /* T if a keyed cksum */
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+
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const struct krb5_crypto_profile *profile;
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+
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int (*random_to_key)(const struct krb5_enctype *krb5,
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const struct krb5_buffer *in,
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struct krb5_buffer *out); /* complete key generation */
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};
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+
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/*
95
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* krb5_api.c
96
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*/
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const struct krb5_enctype *crypto_krb5_find_enctype(u32 enctype);
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#endif /* _CRYPTO_KRB5_H */