/* SPDX-License-Identifier: GPL-2.0+ */
/*
 * Module signature handling.
 *
 * Copyright (C) 2012 Red Hat, Inc. All Rights Reserved.
 * Written by David Howells ([email protected])
 */

#ifndef _LINUX_MODULE_SIGNATURE_H
#define _LINUX_MODULE_SIGNATURE_H

#include <linux/types.h>

/* In stripped ARM and x86-64 modules, ~ is surprisingly rare. */
#define MODULE_SIG_STRING "~Module signature appended~\n"

enum pkey_id_type {
    PKEY_ID_PGP,        /* OpenPGP generated key ID */
    PKEY_ID_X509,        /* X.509 arbitrary subjectKeyIdentifier */
    PKEY_ID_PKCS7,        /* Signature in PKCS#7 message */
};

/*
 * Module signature information block.
 *
 * The constituents of the signature section are, in order:
 *
 *    - Signer's name
 *    - Key identifier
 *    - Signature data
 *    - Information block
 */
struct module_signature {
    u8    algo;        /* Public-key crypto algorithm [0] */
    u8    hash;        /* Digest algorithm [0] */
    u8    id_type;    /* Key identifier type [PKEY_ID_PKCS7] */
    u8    signer_len;    /* Length of signer's name [0] */
    u8    key_id_len;    /* Length of key identifier [0] */
    u8    __pad[3];
    __be32    sig_len;    /* Length of signature data */
};

int mod_check_sig(const struct module_signature *ms, size_t file_len,
          const char *name);

#endif /* _LINUX_MODULE_SIGNATURE_H */