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/* SPDX-License-Identifier: GPL-2.0-only *//* * Copyright (C) 2009-2010 IBM Corporation * * Authors: * Mimi Zohar <zohar@us.ibm.com> */ #ifdef pr_fmt#undef pr_fmt#endif #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt #include <linux/types.h>#include <linux/integrity.h>#include <linux/secure_boot.h>#include <crypto/sha1.h>#include <crypto/hash.h>#include <linux/key.h>#include <linux/audit.h>#include <linux/lsm_hooks.h> enum evm_ima_xattr_type {	IMA_XATTR_DIGEST = 0x01,	EVM_XATTR_HMAC,	EVM_IMA_XATTR_DIGSIG,	IMA_XATTR_DIGEST_NG,	EVM_XATTR_PORTABLE_DIGSIG,	IMA_VERITY_DIGSIG,	IMA_XATTR_LAST}; struct evm_ima_xattr_data {	/* New members must be added within the __struct_group() macro below. */	__struct_group(evm_ima_xattr_data_hdr, hdr, __packed,		u8 type;	);	u8 data[];} __packed;static_assert(offsetof(struct evm_ima_xattr_data, data) == sizeof(struct evm_ima_xattr_data_hdr),	      "struct member likely outside of __struct_group()"); /* Only used in the EVM HMAC code. */struct evm_xattr {	struct evm_ima_xattr_data_hdr data;	u8 digest[SHA1_DIGEST_SIZE];} __packed; #define IMA_MAX_DIGEST_SIZE	HASH_MAX_DIGESTSIZE struct ima_digest_data {	/* New members must be added within the __struct_group() macro below. */	__struct_group(ima_digest_data_hdr, hdr, __packed,	u8 algo;	u8 length;	union {		struct {			u8 unused;			u8 type;		} sha1;		struct {			u8 type;			u8 algo;		} ng;		u8 data[2];	} xattr;	);	u8 digest[];} __packed;static_assert(offsetof(struct ima_digest_data, digest) == sizeof(struct ima_digest_data_hdr),	      "struct member likely outside of __struct_group()"); /* * Instead of wrapping the ima_digest_data struct inside a local structure * with the maximum hash size, define ima_max_digest_data struct. */struct ima_max_digest_data {	struct ima_digest_data_hdr hdr;	u8 digest[HASH_MAX_DIGESTSIZE];} __packed; /* * signature header format v2 - for using with asymmetric keys * * The signature_v2_hdr struct includes a signature format version * to simplify defining new signature formats. * * signature format: * version 2: regular file data hash based signature * version 3: struct ima_file_id data based signature */struct signature_v2_hdr {	uint8_t type;		/* xattr type */	uint8_t version;	/* signature format version */	uint8_t	hash_algo;	/* Digest algorithm [enum hash_algo] */	__be32 keyid;		/* IMA key identifier - not X509/PGP specific */	__be16 sig_size;	/* signature size */	uint8_t sig[];		/* signature payload */} __packed; /* * IMA signature version 3 disambiguates the data that is signed, by * indirectly signing the hash of the ima_file_id structure data, * containing either the fsverity_descriptor struct digest or, in the * future, the regular IMA file hash. * * (The hash of the ima_file_id structure is only of the portion used.) */struct ima_file_id {	__u8 hash_type;		/* xattr type [enum evm_ima_xattr_type] */	__u8 hash_algorithm;	/* Digest algorithm [enum hash_algo] */	__u8 hash[HASH_MAX_DIGESTSIZE];} __packed; int integrity_kernel_read(struct file *file, loff_t offset,			  void *addr, unsigned long count);int __init integrity_fs_init(void);void __init integrity_fs_fini(void); #define INTEGRITY_KEYRING_EVM		0#define INTEGRITY_KEYRING_IMA		1#define INTEGRITY_KEYRING_PLATFORM	2#define INTEGRITY_KEYRING_MACHINE	3#define INTEGRITY_KEYRING_MAX		4 extern struct dentry *integrity_dir; struct modsig; #ifdef CONFIG_INTEGRITY_SIGNATURE int integrity_digsig_verify(const unsigned int id, const char *sig, int siglen,			    const char *digest, int digestlen, u8 algo);int integrity_modsig_verify(unsigned int id, const struct modsig *modsig); int __init integrity_init_keyring(const unsigned int id);int __init integrity_load_x509(const unsigned int id, const char *path);int __init integrity_load_cert(const unsigned int id, const char *source,			       const void *data, size_t len, key_perm_t perm);#else static inline int integrity_digsig_verify(const unsigned int id,					  const char *sig, int siglen,					  const char *digest, int digestlen,					  u8 algo){	return -EOPNOTSUPP;} static inline int integrity_modsig_verify(unsigned int id,					  const struct modsig *modsig){	return -EOPNOTSUPP;} static inline int integrity_init_keyring(const unsigned int id){	return 0;} static inline int __init integrity_load_cert(const unsigned int id,					     const char *source,					     const void *data, size_t len,					     key_perm_t perm){	return 0;}#endif /* CONFIG_INTEGRITY_SIGNATURE */ #ifdef CONFIG_INTEGRITY_ASYMMETRIC_KEYSint asymmetric_verify(struct key *keyring, const char *sig,		      int siglen, const char *data, int datalen);int asymmetric_verify_v3(struct key *keyring, const char *sig,			 int siglen, const char *data, int datalen, u8 algo);#elsestatic inline int asymmetric_verify(struct key *keyring, const char *sig,				    int siglen, const char *data, int datalen){	return -EOPNOTSUPP;} static inline int asymmetric_verify_v3(struct key *keyring,				       const char *sig, int siglen,				       const char *data, int datalen, u8 algo){	return -EOPNOTSUPP;}#endif #ifdef CONFIG_IMA_APPRAISE_MODSIGint ima_modsig_verify(struct key *keyring, const struct modsig *modsig);#elsestatic inline int ima_modsig_verify(struct key *keyring,				    const struct modsig *modsig){	return -EOPNOTSUPP;}#endif #ifdef CONFIG_IMA_LOAD_X509void __init ima_load_x509(void);#elsestatic inline void ima_load_x509(void){}#endif #ifdef CONFIG_EVM_LOAD_X509void __init evm_load_x509(void);#elsestatic inline void evm_load_x509(void){}#endif #ifdef CONFIG_INTEGRITY_AUDIT/* declarations */void integrity_audit_msg(int audit_msgno, struct inode *inode,			 const unsigned char *fname, const char *op,			 const char *cause, int result, int info); void integrity_audit_message(int audit_msgno, struct inode *inode,			     const unsigned char *fname, const char *op,			     const char *cause, int result, int info,			     int errno); static inline struct audit_buffer *integrity_audit_log_start(struct audit_context *ctx, gfp_t gfp_mask, int type){	return audit_log_start(ctx, gfp_mask, type);} #elsestatic inline void integrity_audit_msg(int audit_msgno, struct inode *inode,				       const unsigned char *fname,				       const char *op, const char *cause,				       int result, int info){} static inline void integrity_audit_message(int audit_msgno,					   struct inode *inode,					   const unsigned char *fname,					   const char *op, const char *cause,					   int result, int info, int errno){} static inline struct audit_buffer *integrity_audit_log_start(struct audit_context *ctx, gfp_t gfp_mask, int type){	return NULL;} #endif #ifdef CONFIG_INTEGRITY_PLATFORM_KEYRINGvoid __init add_to_platform_keyring(const char *source, const void *data,				    size_t len);#elsestatic inline void __init add_to_platform_keyring(const char *source,						  const void *data, size_t len){}#endif #ifdef CONFIG_INTEGRITY_MACHINE_KEYRINGvoid __init add_to_machine_keyring(const char *source, const void *data, size_t len);bool __init imputed_trust_enabled(void);#elsestatic inline void __init add_to_machine_keyring(const char *source,						  const void *data, size_t len){} static inline bool __init imputed_trust_enabled(void){	return false;}#endif