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Diffstat (limited to 'security/integrity/ima/ima.h')
| -rw-r--r-- | security/integrity/ima/ima.h | 445 |
1 files changed, 445 insertions, 0 deletions
diff --git a/security/integrity/ima/ima.h b/security/integrity/ima/ima.h new file mode 100644 index 000000000..6ebefec61 --- /dev/null +++ b/security/integrity/ima/ima.h @@ -0,0 +1,445 @@ +/* SPDX-License-Identifier: GPL-2.0-only */ +/* + * Copyright (C) 2005,2006,2007,2008 IBM Corporation + * + * Authors: + * Reiner Sailer <sailer@watson.ibm.com> + * Mimi Zohar <zohar@us.ibm.com> + * + * File: ima.h + * internal Integrity Measurement Architecture (IMA) definitions + */ + +#ifndef __LINUX_IMA_H +#define __LINUX_IMA_H + +#include <linux/types.h> +#include <linux/crypto.h> +#include <linux/fs.h> +#include <linux/security.h> +#include <linux/hash.h> +#include <linux/tpm.h> +#include <linux/audit.h> +#include <crypto/hash_info.h> + +#include "../integrity.h" + +#ifdef CONFIG_HAVE_IMA_KEXEC +#include <asm/ima.h> +#endif + +enum ima_show_type { IMA_SHOW_BINARY, IMA_SHOW_BINARY_NO_FIELD_LEN, + IMA_SHOW_BINARY_OLD_STRING_FMT, IMA_SHOW_ASCII }; +enum tpm_pcrs { TPM_PCR0 = 0, TPM_PCR8 = 8, TPM_PCR10 = 10 }; + +/* digest size for IMA, fits SHA1 or MD5 */ +#define IMA_DIGEST_SIZE SHA1_DIGEST_SIZE +#define IMA_EVENT_NAME_LEN_MAX 255 + +#define IMA_HASH_BITS 10 +#define IMA_MEASURE_HTABLE_SIZE (1 << IMA_HASH_BITS) + +#define IMA_TEMPLATE_FIELD_ID_MAX_LEN 16 +#define IMA_TEMPLATE_NUM_FIELDS_MAX 15 + +#define IMA_TEMPLATE_IMA_NAME "ima" +#define IMA_TEMPLATE_IMA_FMT "d|n" + +#define NR_BANKS(chip) ((chip != NULL) ? chip->nr_allocated_banks : 0) + +/* current content of the policy */ +extern int ima_policy_flag; + +/* set during initialization */ +extern int ima_hash_algo; +extern int ima_sha1_idx __ro_after_init; +extern int ima_hash_algo_idx __ro_after_init; +extern int ima_extra_slots __ro_after_init; +extern int ima_appraise; +extern struct tpm_chip *ima_tpm_chip; +extern const char boot_aggregate_name[]; + +/* IMA event related data */ +struct ima_event_data { + struct integrity_iint_cache *iint; + struct file *file; + const unsigned char *filename; + struct evm_ima_xattr_data *xattr_value; + int xattr_len; + const struct modsig *modsig; + const char *violation; + const void *buf; + int buf_len; +}; + +/* IMA template field data definition */ +struct ima_field_data { + u8 *data; + u32 len; +}; + +/* IMA template field definition */ +struct ima_template_field { + const char field_id[IMA_TEMPLATE_FIELD_ID_MAX_LEN]; + int (*field_init)(struct ima_event_data *event_data, + struct ima_field_data *field_data); + void (*field_show)(struct seq_file *m, enum ima_show_type show, + struct ima_field_data *field_data); +}; + +/* IMA template descriptor definition */ +struct ima_template_desc { + struct list_head list; + char *name; + char *fmt; + int num_fields; + const struct ima_template_field **fields; +}; + +struct ima_template_entry { + int pcr; + struct tpm_digest *digests; + struct ima_template_desc *template_desc; /* template descriptor */ + u32 template_data_len; + struct ima_field_data template_data[]; /* template related data */ +}; + +struct ima_queue_entry { + struct hlist_node hnext; /* place in hash collision list */ + struct list_head later; /* place in ima_measurements list */ + struct ima_template_entry *entry; +}; +extern struct list_head ima_measurements; /* list of all measurements */ + +/* Some details preceding the binary serialized measurement list */ +struct ima_kexec_hdr { + u16 version; + u16 _reserved0; + u32 _reserved1; + u64 buffer_size; + u64 count; +}; + +extern const int read_idmap[]; + +#ifdef CONFIG_HAVE_IMA_KEXEC +void ima_load_kexec_buffer(void); +#else +static inline void ima_load_kexec_buffer(void) {} +#endif /* CONFIG_HAVE_IMA_KEXEC */ + +/* + * The default binary_runtime_measurements list format is defined as the + * platform native format. The canonical format is defined as little-endian. + */ +extern bool ima_canonical_fmt; + +/* Internal IMA function definitions */ +int ima_init(void); +int ima_fs_init(void); +int ima_add_template_entry(struct ima_template_entry *entry, int violation, + const char *op, struct inode *inode, + const unsigned char *filename); +int ima_calc_file_hash(struct file *file, struct ima_digest_data *hash); +int ima_calc_buffer_hash(const void *buf, loff_t len, + struct ima_digest_data *hash); +int ima_calc_field_array_hash(struct ima_field_data *field_data, + struct ima_template_entry *entry); +int ima_calc_boot_aggregate(struct ima_digest_data *hash); +void ima_add_violation(struct file *file, const unsigned char *filename, + struct integrity_iint_cache *iint, + const char *op, const char *cause); +int ima_init_crypto(void); +void ima_putc(struct seq_file *m, void *data, int datalen); +void ima_print_digest(struct seq_file *m, u8 *digest, u32 size); +int template_desc_init_fields(const char *template_fmt, + const struct ima_template_field ***fields, + int *num_fields); +struct ima_template_desc *ima_template_desc_current(void); +struct ima_template_desc *lookup_template_desc(const char *name); +bool ima_template_has_modsig(const struct ima_template_desc *ima_template); +int ima_restore_measurement_entry(struct ima_template_entry *entry); +int ima_restore_measurement_list(loff_t bufsize, void *buf); +int ima_measurements_show(struct seq_file *m, void *v); +unsigned long ima_get_binary_runtime_size(void); +int ima_init_template(void); +void ima_init_template_list(void); +int __init ima_init_digests(void); +int ima_lsm_policy_change(struct notifier_block *nb, unsigned long event, + void *lsm_data); + +/* + * used to protect h_table and sha_table + */ +extern spinlock_t ima_queue_lock; + +struct ima_h_table { + atomic_long_t len; /* number of stored measurements in the list */ + atomic_long_t violations; + struct hlist_head queue[IMA_MEASURE_HTABLE_SIZE]; +}; +extern struct ima_h_table ima_htable; + +static inline unsigned int ima_hash_key(u8 *digest) +{ + /* there is no point in taking a hash of part of a digest */ + return (digest[0] | digest[1] << 8) % IMA_MEASURE_HTABLE_SIZE; +} + +#define __ima_hooks(hook) \ + hook(NONE, none) \ + hook(FILE_CHECK, file) \ + hook(MMAP_CHECK, mmap) \ + hook(BPRM_CHECK, bprm) \ + hook(CREDS_CHECK, creds) \ + hook(POST_SETATTR, post_setattr) \ + hook(MODULE_CHECK, module) \ + hook(FIRMWARE_CHECK, firmware) \ + hook(KEXEC_KERNEL_CHECK, kexec_kernel) \ + hook(KEXEC_INITRAMFS_CHECK, kexec_initramfs) \ + hook(POLICY_CHECK, policy) \ + hook(KEXEC_CMDLINE, kexec_cmdline) \ + hook(KEY_CHECK, key) \ + hook(MAX_CHECK, none) + +#define __ima_hook_enumify(ENUM, str) ENUM, +#define __ima_stringify(arg) (#arg) +#define __ima_hook_measuring_stringify(ENUM, str) \ + (__ima_stringify(measuring_ ##str)), + +enum ima_hooks { + __ima_hooks(__ima_hook_enumify) +}; + +static const char * const ima_hooks_measure_str[] = { + __ima_hooks(__ima_hook_measuring_stringify) +}; + +static inline const char *func_measure_str(enum ima_hooks func) +{ + if (func >= MAX_CHECK) + return ima_hooks_measure_str[NONE]; + + return ima_hooks_measure_str[func]; +} + +extern const char *const func_tokens[]; + +struct modsig; + +#ifdef CONFIG_IMA_QUEUE_EARLY_BOOT_KEYS +/* + * To track keys that need to be measured. + */ +struct ima_key_entry { + struct list_head list; + void *payload; + size_t payload_len; + char *keyring_name; +}; +void ima_init_key_queue(void); +bool ima_should_queue_key(void); +bool ima_queue_key(struct key *keyring, const void *payload, + size_t payload_len); +void ima_process_queued_keys(void); +#else +static inline void ima_init_key_queue(void) {} +static inline bool ima_should_queue_key(void) { return false; } +static inline bool ima_queue_key(struct key *keyring, + const void *payload, + size_t payload_len) { return false; } +static inline void ima_process_queued_keys(void) {} +#endif /* CONFIG_IMA_QUEUE_EARLY_BOOT_KEYS */ + +/* LIM API function definitions */ +int ima_get_action(struct inode *inode, const struct cred *cred, u32 secid, + int mask, enum ima_hooks func, int *pcr, + struct ima_template_desc **template_desc, + const char *keyring); +int ima_must_measure(struct inode *inode, int mask, enum ima_hooks func); +int ima_collect_measurement(struct integrity_iint_cache *iint, + struct file *file, void *buf, loff_t size, + enum hash_algo algo, struct modsig *modsig); +void ima_store_measurement(struct integrity_iint_cache *iint, struct file *file, + const unsigned char *filename, + struct evm_ima_xattr_data *xattr_value, + int xattr_len, const struct modsig *modsig, int pcr, + struct ima_template_desc *template_desc); +void process_buffer_measurement(struct inode *inode, const void *buf, int size, + const char *eventname, enum ima_hooks func, + int pcr, const char *keyring); +void ima_audit_measurement(struct integrity_iint_cache *iint, + const unsigned char *filename); +int ima_alloc_init_template(struct ima_event_data *event_data, + struct ima_template_entry **entry, + struct ima_template_desc *template_desc); +int ima_store_template(struct ima_template_entry *entry, int violation, + struct inode *inode, + const unsigned char *filename, int pcr); +void ima_free_template_entry(struct ima_template_entry *entry); +const char *ima_d_path(const struct path *path, char **pathbuf, char *filename); + +/* IMA policy related functions */ +int ima_match_policy(struct inode *inode, const struct cred *cred, u32 secid, + enum ima_hooks func, int mask, int flags, int *pcr, + struct ima_template_desc **template_desc, + const char *keyring); +void ima_init_policy(void); +void ima_update_policy(void); +void ima_update_policy_flag(void); +ssize_t ima_parse_add_rule(char *); +void ima_delete_rules(void); +int ima_check_policy(void); +void *ima_policy_start(struct seq_file *m, loff_t *pos); +void *ima_policy_next(struct seq_file *m, void *v, loff_t *pos); +void ima_policy_stop(struct seq_file *m, void *v); +int ima_policy_show(struct seq_file *m, void *v); + +/* Appraise integrity measurements */ +#define IMA_APPRAISE_ENFORCE 0x01 +#define IMA_APPRAISE_FIX 0x02 +#define IMA_APPRAISE_LOG 0x04 +#define IMA_APPRAISE_MODULES 0x08 +#define IMA_APPRAISE_FIRMWARE 0x10 +#define IMA_APPRAISE_POLICY 0x20 +#define IMA_APPRAISE_KEXEC 0x40 + +#ifdef CONFIG_IMA_APPRAISE +int ima_check_blacklist(struct integrity_iint_cache *iint, + const struct modsig *modsig, int pcr); +int ima_appraise_measurement(enum ima_hooks func, + struct integrity_iint_cache *iint, + struct file *file, const unsigned char *filename, + struct evm_ima_xattr_data *xattr_value, + int xattr_len, const struct modsig *modsig); +int ima_must_appraise(struct inode *inode, int mask, enum ima_hooks func); +void ima_update_xattr(struct integrity_iint_cache *iint, struct file *file); +enum integrity_status ima_get_cache_status(struct integrity_iint_cache *iint, + enum ima_hooks func); +enum hash_algo ima_get_hash_algo(struct evm_ima_xattr_data *xattr_value, + int xattr_len); +int ima_read_xattr(struct dentry *dentry, + struct evm_ima_xattr_data **xattr_value); + +#else +static inline int ima_check_blacklist(struct integrity_iint_cache *iint, + const struct modsig *modsig, int pcr) +{ + return 0; +} + +static inline int ima_appraise_measurement(enum ima_hooks func, + struct integrity_iint_cache *iint, + struct file *file, + const unsigned char *filename, + struct evm_ima_xattr_data *xattr_value, + int xattr_len, + const struct modsig *modsig) +{ + return INTEGRITY_UNKNOWN; +} + +static inline int ima_must_appraise(struct inode *inode, int mask, + enum ima_hooks func) +{ + return 0; +} + +static inline void ima_update_xattr(struct integrity_iint_cache *iint, + struct file *file) +{ +} + +static inline enum integrity_status ima_get_cache_status(struct integrity_iint_cache + *iint, + enum ima_hooks func) +{ + return INTEGRITY_UNKNOWN; +} + +static inline enum hash_algo +ima_get_hash_algo(struct evm_ima_xattr_data *xattr_value, int xattr_len) +{ + return ima_hash_algo; +} + +static inline int ima_read_xattr(struct dentry *dentry, + struct evm_ima_xattr_data **xattr_value) +{ + return 0; +} + +#endif /* CONFIG_IMA_APPRAISE */ + +#ifdef CONFIG_IMA_APPRAISE_MODSIG +int ima_read_modsig(enum ima_hooks func, const void *buf, loff_t buf_len, + struct modsig **modsig); +void ima_collect_modsig(struct modsig *modsig, const void *buf, loff_t size); +int ima_get_modsig_digest(const struct modsig *modsig, enum hash_algo *algo, + const u8 **digest, u32 *digest_size); +int ima_get_raw_modsig(const struct modsig *modsig, const void **data, + u32 *data_len); +void ima_free_modsig(struct modsig *modsig); +#else +static inline int ima_read_modsig(enum ima_hooks func, const void *buf, + loff_t buf_len, struct modsig **modsig) +{ + return -EOPNOTSUPP; +} + +static inline void ima_collect_modsig(struct modsig *modsig, const void *buf, + loff_t size) +{ +} + +static inline int ima_get_modsig_digest(const struct modsig *modsig, + enum hash_algo *algo, const u8 **digest, + u32 *digest_size) +{ + return -EOPNOTSUPP; +} + +static inline int ima_get_raw_modsig(const struct modsig *modsig, + const void **data, u32 *data_len) +{ + return -EOPNOTSUPP; +} + +static inline void ima_free_modsig(struct modsig *modsig) +{ +} +#endif /* CONFIG_IMA_APPRAISE_MODSIG */ + +/* LSM based policy rules require audit */ +#ifdef CONFIG_IMA_LSM_RULES + +#define ima_filter_rule_init security_audit_rule_init +#define ima_filter_rule_free security_audit_rule_free +#define ima_filter_rule_match security_audit_rule_match + +#else + +static inline int ima_filter_rule_init(u32 field, u32 op, char *rulestr, + void **lsmrule) +{ + return -EINVAL; +} + +static inline void ima_filter_rule_free(void *lsmrule) +{ +} + +static inline int ima_filter_rule_match(u32 secid, u32 field, u32 op, + void *lsmrule) +{ + return -EINVAL; +} +#endif /* CONFIG_IMA_LSM_RULES */ + +#ifdef CONFIG_IMA_READ_POLICY +#define POLICY_FILE_FLAGS (S_IWUSR | S_IRUSR) +#else +#define POLICY_FILE_FLAGS S_IWUSR +#endif /* CONFIG_IMA_READ_POLICY */ + +#endif /* __LINUX_IMA_H */ |