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Diffstat (limited to 'security/integrity/integrity.h')
| -rw-r--r-- | security/integrity/integrity.h | 281 |
1 files changed, 281 insertions, 0 deletions
diff --git a/security/integrity/integrity.h b/security/integrity/integrity.h new file mode 100644 index 000000000..0c581c03c --- /dev/null +++ b/security/integrity/integrity.h @@ -0,0 +1,281 @@ +/* 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_KEYS +int 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); +#else +static 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_MODSIG +int ima_modsig_verify(struct key *keyring, const struct modsig *modsig); +#else +static inline int ima_modsig_verify(struct key *keyring, + const struct modsig *modsig) +{ + return -EOPNOTSUPP; +} +#endif + +#ifdef CONFIG_IMA_LOAD_X509 +void __init ima_load_x509(void); +#else +static inline void ima_load_x509(void) +{ +} +#endif + +#ifdef CONFIG_EVM_LOAD_X509 +void __init evm_load_x509(void); +#else +static 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); +} + +#else +static 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_KEYRING +void __init add_to_platform_keyring(const char *source, const void *data, + size_t len); +#else +static inline void __init add_to_platform_keyring(const char *source, + const void *data, size_t len) +{ +} +#endif + +#ifdef CONFIG_INTEGRITY_MACHINE_KEYRING +void __init add_to_machine_keyring(const char *source, const void *data, size_t len); +bool __init imputed_trust_enabled(void); +#else +static 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 |
