linux/crypto/asymmetric_keys/x509_parser.h
Lukas Wunner 5c6ca9d936 X.509: Introduce scope-based x509_certificate allocation
Add a DEFINE_FREE() clause for x509_certificate structs and use it in
x509_cert_parse() and x509_key_preparse().  These are the only functions
where scope-based x509_certificate allocation currently makes sense.
A third user will be introduced with the forthcoming SPDM library
(Security Protocol and Data Model) for PCI device authentication.

Unlike most other DEFINE_FREE() clauses, this one checks for IS_ERR()
instead of NULL before calling x509_free_certificate() at end of scope.
That's because the "constructor" of x509_certificate structs,
x509_cert_parse(), returns a valid pointer or an ERR_PTR(), but never
NULL.

Comparing the Assembler output before/after has shown they are identical,
save for the fact that gcc-12 always generates two return paths when
__cleanup() is used, one for the success case and one for the error case.

In x509_cert_parse(), add a hint for the compiler that kzalloc() never
returns an ERR_PTR().  Otherwise the compiler adds a gratuitous IS_ERR()
check on return.  Introduce an assume() macro for this which can be
re-used elsewhere in the kernel to provide hints for the compiler.

Suggested-by: Jonathan Cameron <Jonathan.Cameron@Huawei.com>
Link: https://lore.kernel.org/all/20231003153937.000034ca@Huawei.com/
Link: https://lwn.net/Articles/934679/
Signed-off-by: Lukas Wunner <lukas@wunner.de>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
2024-04-12 15:07:53 +08:00

60 lines
2.2 KiB
C

/* SPDX-License-Identifier: GPL-2.0-or-later */
/* X.509 certificate parser internal definitions
*
* Copyright (C) 2012 Red Hat, Inc. All Rights Reserved.
* Written by David Howells (dhowells@redhat.com)
*/
#include <linux/cleanup.h>
#include <linux/time.h>
#include <crypto/public_key.h>
#include <keys/asymmetric-type.h>
struct x509_certificate {
struct x509_certificate *next;
struct x509_certificate *signer; /* Certificate that signed this one */
struct public_key *pub; /* Public key details */
struct public_key_signature *sig; /* Signature parameters */
char *issuer; /* Name of certificate issuer */
char *subject; /* Name of certificate subject */
struct asymmetric_key_id *id; /* Issuer + Serial number */
struct asymmetric_key_id *skid; /* Subject + subjectKeyId (optional) */
time64_t valid_from;
time64_t valid_to;
const void *tbs; /* Signed data */
unsigned tbs_size; /* Size of signed data */
unsigned raw_sig_size; /* Size of signature */
const void *raw_sig; /* Signature data */
const void *raw_serial; /* Raw serial number in ASN.1 */
unsigned raw_serial_size;
unsigned raw_issuer_size;
const void *raw_issuer; /* Raw issuer name in ASN.1 */
const void *raw_subject; /* Raw subject name in ASN.1 */
unsigned raw_subject_size;
unsigned raw_skid_size;
const void *raw_skid; /* Raw subjectKeyId in ASN.1 */
unsigned index;
bool seen; /* Infinite recursion prevention */
bool verified;
bool self_signed; /* T if self-signed (check unsupported_sig too) */
bool unsupported_sig; /* T if signature uses unsupported crypto */
bool blacklisted;
};
/*
* x509_cert_parser.c
*/
extern void x509_free_certificate(struct x509_certificate *cert);
DEFINE_FREE(x509_free_certificate, struct x509_certificate *,
if (!IS_ERR(_T)) x509_free_certificate(_T))
extern struct x509_certificate *x509_cert_parse(const void *data, size_t datalen);
extern int x509_decode_time(time64_t *_t, size_t hdrlen,
unsigned char tag,
const unsigned char *value, size_t vlen);
/*
* x509_public_key.c
*/
extern int x509_get_sig_params(struct x509_certificate *cert);
extern int x509_check_for_self_signed(struct x509_certificate *cert);