audit.h

/* SPDX-License-Identifier: GPL-2.0-or-later */
/* audit.h -- Auditing support
 *
 * Copyright 2003-2004 Red Hat Inc., Durham, North Carolina.
 * All Rights Reserved.
 *
 * Written by Rickard E. (Rik) Faith <faith@redhat.com>
 */
#ifndef _LINUX_AUDIT_H_
#define _LINUX_AUDIT_H_

#include <linux/sched.h>
#include <linux/ptrace.h>
#include <linux/audit_arch.h>
#include <uapi/linux/audit.h>
#include <uapi/linux/netfilter/nf_tables.h>
#include <uapi/linux/fanotify.h>

#define AUDIT_INO_UNSET ((unsigned long)-1)
#define AUDIT_DEV_UNSET ((dev_t)-1)

struct audit_sig_info {
	uid_t		uid;
	pid_t		pid;
	char		ctx[];
};

struct audit_buffer;
struct audit_context;
struct inode;
struct netlink_skb_parms;
struct path;
struct linux_binprm;
struct mq_attr;
struct mqstat;
struct audit_watch;
struct audit_tree;
struct sk_buff;

struct audit_krule {
	u32			pflags;
	u32			flags;
	u32			listnr;
	u32			action;
	u32			mask[AUDIT_BITMASK_SIZE];
	u32			buflen; /* for data alloc on list rules */
	u32			field_count;
	char			*filterkey; /* ties events to rules */
	struct audit_field	*fields;
	struct audit_field	*arch_f; /* quick access to arch field */
	struct audit_field	*inode_f; /* quick access to an inode field */
	struct audit_watch	*watch;	/* associated watch */
	struct audit_tree	*tree;	/* associated watched tree */
	struct audit_fsnotify_mark	*exe;
	struct list_head	rlist;	/* entry in audit_{watch,tree}.rules list */
	struct list_head	list;	/* for AUDIT_LIST* purposes only */
	u64			prio;
};

/* Flag to indicate legacy AUDIT_LOGINUID unset usage */
#define AUDIT_LOGINUID_LEGACY		0x1

struct audit_field {
	u32				type;
	union {
		u32			val;
		kuid_t			uid;
		kgid_t			gid;
		struct {
			char		*lsm_str;
			void		*lsm_rule;
		};
	};
	u32				op;
};

enum audit_ntp_type {
	AUDIT_NTP_OFFSET,
	AUDIT_NTP_FREQ,
	AUDIT_NTP_STATUS,
	AUDIT_NTP_TAI,
	AUDIT_NTP_TICK,
	AUDIT_NTP_ADJUST,

	AUDIT_NTP_NVALS /* count */
};

#ifdef CONFIG_AUDITSYSCALL
struct audit_ntp_val {
	long long oldval, newval;
};

struct audit_ntp_data {
	struct audit_ntp_val vals[AUDIT_NTP_NVALS];
};
#else
struct audit_ntp_data {};
#endif

enum audit_nfcfgop {
	AUDIT_XT_OP_REGISTER,
	AUDIT_XT_OP_REPLACE,
	AUDIT_XT_OP_UNREGISTER,
	AUDIT_NFT_OP_TABLE_REGISTER,
	AUDIT_NFT_OP_TABLE_UNREGISTER,
	AUDIT_NFT_OP_CHAIN_REGISTER,
	AUDIT_NFT_OP_CHAIN_UNREGISTER,
	AUDIT_NFT_OP_RULE_REGISTER,
	AUDIT_NFT_OP_RULE_UNREGISTER,
	AUDIT_NFT_OP_SET_REGISTER,
	AUDIT_NFT_OP_SET_UNREGISTER,
	AUDIT_NFT_OP_SETELEM_REGISTER,
	AUDIT_NFT_OP_SETELEM_UNREGISTER,
	AUDIT_NFT_OP_GEN_REGISTER,
	AUDIT_NFT_OP_OBJ_REGISTER,
	AUDIT_NFT_OP_OBJ_UNREGISTER,
	AUDIT_NFT_OP_OBJ_RESET,
	AUDIT_NFT_OP_FLOWTABLE_REGISTER,
	AUDIT_NFT_OP_FLOWTABLE_UNREGISTER,
	AUDIT_NFT_OP_INVALID,
};

extern int __init audit_register_class(int class, unsigned *list);
extern int audit_classify_syscall(int abi, unsigned syscall);
extern int audit_classify_arch(int arch);
/* only for compat system calls */
extern unsigned compat_write_class[];
extern unsigned compat_read_class[];
extern unsigned compat_dir_class[];
extern unsigned compat_chattr_class[];
extern unsigned compat_signal_class[];

extern int audit_classify_compat_syscall(int abi, unsigned syscall);

/* audit_names->type values */
#define	AUDIT_TYPE_UNKNOWN	0	/* we don't know yet */
#define	AUDIT_TYPE_NORMAL	1	/* a "normal" audit record */
#define	AUDIT_TYPE_PARENT	2	/* a parent audit record */
#define	AUDIT_TYPE_CHILD_DELETE 3	/* a child being deleted */
#define	AUDIT_TYPE_CHILD_CREATE 4	/* a child being created */

/* maximized args number that audit_socketcall can process */
#define AUDITSC_ARGS		6

/* bit values for ->signal->audit_tty */
#define AUDIT_TTY_ENABLE	BIT(0)
#define AUDIT_TTY_LOG_PASSWD	BIT(1)

struct filename;

#define AUDIT_OFF	0
#define AUDIT_ON	1
#define AUDIT_LOCKED	2
#ifdef CONFIG_AUDIT
/* These are defined in audit.c */
				/* Public API */
extern __printf(4, 5)
void audit_log(struct audit_context *ctx, gfp_t gfp_mask, int type,
	       const char *fmt, ...);

extern struct audit_buffer *audit_log_start(struct audit_context *ctx, gfp_t gfp_mask, int type);
extern __printf(2, 3)
void audit_log_format(struct audit_buffer *ab, const char *fmt, ...);
extern void		    audit_log_end(struct audit_buffer *ab);
extern bool		    audit_string_contains_control(const char *string,
							  size_t len);
extern void		    audit_log_n_hex(struct audit_buffer *ab,
					  const unsigned char *buf,
					  size_t len);
extern void		    audit_log_n_string(struct audit_buffer *ab,
					       const char *buf,
					       size_t n);
extern void		    audit_log_n_untrustedstring(struct audit_buffer *ab,
							const char *string,
							size_t n);
extern void		    audit_log_untrustedstring(struct audit_buffer *ab,
						      const char *string);
extern void		    audit_log_d_path(struct audit_buffer *ab,
					     const char *prefix,
					     const struct path *path);
extern void		    audit_log_key(struct audit_buffer *ab,
					  char *key);
extern void		    audit_log_path_denied(int type,
						  const char *operation);
extern void		    audit_log_lost(const char *message);

extern int audit_log_task_context(struct audit_buffer *ab);
extern void audit_log_task_info(struct audit_buffer *ab);

extern int		    audit_update_lsm_rules(void);

				/* Private API (for audit.c only) */
extern int audit_rule_change(int type, int seq, void *data, size_t datasz);
extern int audit_list_rules_send(struct sk_buff *request_skb, int seq);

extern int audit_set_loginuid(kuid_t loginuid);

static inline kuid_t audit_get_loginuid(struct task_struct *tsk)
{
	return tsk->loginuid;
}

static inline unsigned int audit_get_sessionid(struct task_struct *tsk)
{
	return tsk->sessionid;
}

extern u32 audit_enabled;

extern int audit_signal_info(int sig, struct task_struct *t);

#else /* CONFIG_AUDIT */
static inline __printf(4, 5)
void audit_log(struct audit_context *ctx, gfp_t gfp_mask, int type,
	       const char *fmt, ...)
{ }
static inline struct audit_buffer *audit_log_start(struct audit_context *ctx,
						   gfp_t gfp_mask, int type)
{
	return NULL;
}
static inline __printf(2, 3)
void audit_log_format(struct audit_buffer *ab, const char *fmt, ...)
{ }
static inline void audit_log_end(struct audit_buffer *ab)
{ }
static inline void audit_log_n_hex(struct audit_buffer *ab,
				   const unsigned char *buf, size_t len)
{ }
static inline void audit_log_n_string(struct audit_buffer *ab,
				      const char *buf, size_t n)
{ }
static inline void  audit_log_n_untrustedstring(struct audit_buffer *ab,
						const char *string, size_t n)
{ }
static inline void audit_log_untrustedstring(struct audit_buffer *ab,
					     const char *string)
{ }
static inline void audit_log_d_path(struct audit_buffer *ab,
				    const char *prefix,
				    const struct path *path)
{ }
static inline void audit_log_key(struct audit_buffer *ab, char *key)
{ }
static inline void audit_log_path_denied(int type, const char *operation)
{ }
static inline int audit_log_task_context(struct audit_buffer *ab)
{
	return 0;
}
static inline void audit_log_task_info(struct audit_buffer *ab)
{ }

static inline kuid_t audit_get_loginuid(struct task_struct *tsk)
{
	return INVALID_UID;
}

static inline unsigned int audit_get_sessionid(struct task_struct *tsk)
{
	return AUDIT_SID_UNSET;
}

#define audit_enabled AUDIT_OFF

static inline int audit_signal_info(int sig, struct task_struct *t)
{
	return 0;
}

#endif /* CONFIG_AUDIT */

#ifdef CONFIG_AUDIT_COMPAT_GENERIC
#define audit_is_compat(arch)  (!((arch) & __AUDIT_ARCH_64BIT))
#else
#define audit_is_compat(arch)  false
#endif

#define AUDIT_INODE_PARENT	1	/* dentry represents the parent */
#define AUDIT_INODE_HIDDEN	2	/* audit record should be hidden */
#define AUDIT_INODE_NOEVAL	4	/* audit record incomplete */

#ifdef CONFIG_AUDITSYSCALL
#include <asm/syscall.h> /* for syscall_get_arch() */

/* These are defined in auditsc.c */
				/* Public API */
extern int  audit_alloc(struct task_struct *task);
extern void __audit_free(struct task_struct *task);
extern void __audit_uring_entry(u8 op);
extern void __audit_uring_exit(int success, long code);
extern void __audit_syscall_entry(int major, unsigned long a0, unsigned long a1,
				  unsigned long a2, unsigned long a3);
extern void __audit_syscall_exit(int ret_success, long ret_value);
extern struct filename *__audit_reusename(const __user char *uptr);
extern void __audit_getname(struct filename *name);
extern void __audit_inode(struct filename *name, const struct dentry *dentry,
				unsigned int flags);
extern void __audit_file(const struct file *);
extern void __audit_inode_child(struct inode *parent,
				const struct dentry *dentry,
				const unsigned char type);
extern void audit_seccomp(unsigned long syscall, long signr, int code);
extern void audit_seccomp_actions_logged(const char *names,
					 const char *old_names, int res);
extern void __audit_ptrace(struct task_struct *t);

static inline void audit_set_context(struct task_struct *task, struct audit_context *ctx)
{
	task->audit_context = ctx;
}

static inline struct audit_context *audit_context(void)
{
	return current->audit_context;
}

static inline bool audit_dummy_context(void)
{
	void *p = audit_context();
	return !p || *(int *)p;
}
static inline void audit_free(struct task_struct *task)
{
	if (unlikely(task->audit_context))
		__audit_free(task);
}
static inline void audit_uring_entry(u8 op)
{
	/*
	 * We intentionally check audit_context() before audit_enabled as most
	 * Linux systems (as of ~2021) rely on systemd which forces audit to
	 * be enabled regardless of the user's audit configuration.
	 */
	if (unlikely(audit_context() && audit_enabled))
		__audit_uring_entry(op);
}
static inline void audit_uring_exit(int success, long code)
{
	if (unlikely(audit_context()))
		__audit_uring_exit(success, code);
}
static inline void audit_syscall_entry(int major, unsigned long a0,
				       unsigned long a1, unsigned long a2,
				       unsigned long a3)
{
	if (unlikely(audit_context()))
		__audit_syscall_entry(major, a0, a1, a2, a3);
}
static inline void audit_syscall_exit(void *pt_regs)
{
	if (unlikely(audit_context())) {
		int success = is_syscall_success(pt_regs);
		long return_code = regs_return_value(pt_regs);

		__audit_syscall_exit(success, return_code);
	}
}
static inline struct filename *audit_reusename(const __user char *name)
{
	if (unlikely(!audit_dummy_context()))
		return __audit_reusename(name);
	return NULL;
}
static inline void audit_getname(struct filename *name)
{
	if (unlikely(!audit_dummy_context()))
		__audit_getname(name);
}
static inline void audit_inode(struct filename *name,
				const struct dentry *dentry,
				unsigned int aflags) {
	if (unlikely(!audit_dummy_context()))
		__audit_inode(name, dentry, aflags);
}
static inline void audit_file(struct file *file)
{
	if (unlikely(!audit_dummy_context()))
		__audit_file(file);
}
static inline void audit_inode_parent_hidden(struct filename *name,
						const struct dentry *dentry)
{
	if (unlikely(!audit_dummy_context()))
		__audit_inode(name, dentry,
				AUDIT_INODE_PARENT | AUDIT_INODE_HIDDEN);
}
static inline void audit_inode_child(struct inode *parent,
				     const struct dentry *dentry,
				     const unsigned char type) {
	if (unlikely(!audit_dummy_context()))
		__audit_inode_child(parent, dentry, type);
}
void audit_core_dumps(long signr);

static inline void audit_ptrace(struct task_struct *t)
{
	if (unlikely(!audit_dummy_context()))
		__audit_ptrace(t);
}

				/* Private API (for audit.c only) */
extern void __audit_ipc_obj(struct kern_ipc_perm *ipcp);
extern void __audit_ipc_set_perm(unsigned long qbytes, uid_t uid, gid_t gid, umode_t mode);
extern void __audit_bprm(struct linux_binprm *bprm);
extern int __audit_socketcall(int nargs, unsigned long *args);
extern int __audit_sockaddr(int len, void *addr);
extern void __audit_fd_pair(int fd1, int fd2);
extern void __audit_mq_open(int oflag, umode_t mode, struct mq_attr *attr);
extern void __audit_mq_sendrecv(mqd_t mqdes, size_t msg_len, unsigned int msg_prio, const struct timespec64 *abs_timeout);
extern void __audit_mq_notify(mqd_t mqdes, const struct sigevent *notification);
extern void __audit_mq_getsetattr(mqd_t mqdes, struct mq_attr *mqstat);
extern int __audit_log_bprm_fcaps(struct linux_binprm *bprm,
				  const struct cred *new,
				  const struct cred *old);
extern void __audit_log_capset(const struct cred *new, const struct cred *old);
extern void __audit_mmap_fd(int fd, int flags);
extern void __audit_openat2_how(struct open_how *how);
extern void __audit_log_kern_module(char *name);
extern void __audit_fanotify(u32 response, struct fanotify_response_info_audit_rule *friar);
extern void __audit_tk_injoffset(struct timespec64 offset);
extern void __audit_ntp_log(const struct audit_ntp_data *ad);
extern void __audit_log_nfcfg(const char *name, u8 af, unsigned int nentries,
			      enum audit_nfcfgop op, gfp_t gfp);

static inline void audit_ipc_obj(struct kern_ipc_perm *ipcp)
{
	if (unlikely(!audit_dummy_context()))
		__audit_ipc_obj(ipcp);
}
static inline void audit_fd_pair(int fd1, int fd2)
{
	if (unlikely(!audit_dummy_context()))
		__audit_fd_pair(fd1, fd2);
}
static inline void audit_ipc_set_perm(unsigned long qbytes, uid_t uid, gid_t gid, umode_t mode)
{
	if (unlikely(!audit_dummy_context()))
		__audit_ipc_set_perm(qbytes, uid, gid, mode);
}
static inline void audit_bprm(struct linux_binprm *bprm)
{
	if (unlikely(!audit_dummy_context()))
		__audit_bprm(bprm);
}
static inline int audit_socketcall(int nargs, unsigned long *args)
{
	if (unlikely(!audit_dummy_context()))
		return __audit_socketcall(nargs, args);
	return 0;
}

static inline int audit_socketcall_compat(int nargs, u32 *args)
{
	unsigned long a[AUDITSC_ARGS];
	int i;

	if (audit_dummy_context())
		return 0;

	for (i = 0; i < nargs; i++)
		a[i] = (unsigned long)args[i];
	return __audit_socketcall(nargs, a);
}

static inline int audit_sockaddr(int len, void *addr)
{
	if (unlikely(!audit_dummy_context()))
		return __audit_sockaddr(len, addr);
	return 0;
}
static inline void audit_mq_open(int oflag, umode_t mode, struct mq_attr *attr)
{
	if (unlikely(!audit_dummy_context()))
		__audit_mq_open(oflag, mode, attr);
}
static inline void audit_mq_sendrecv(mqd_t mqdes, size_t msg_len, unsigned int msg_prio, const struct timespec64 *abs_timeout)
{
	if (unlikely(!audit_dummy_context()))
		__audit_mq_sendrecv(mqdes, msg_len, msg_prio, abs_timeout);
}
static inline void audit_mq_notify(mqd_t mqdes, const struct sigevent *notification)
{
	if (unlikely(!audit_dummy_context()))
		__audit_mq_notify(mqdes, notification);
}
static inline void audit_mq_getsetattr(mqd_t mqdes, struct mq_attr *mqstat)
{
	if (unlikely(!audit_dummy_context()))
		__audit_mq_getsetattr(mqdes, mqstat);
}

static inline int audit_log_bprm_fcaps(struct linux_binprm *bprm,
				       const struct cred *new,
				       const struct cred *old)
{
	if (unlikely(!audit_dummy_context()))
		return __audit_log_bprm_fcaps(bprm, new, old);
	return 0;
}

static inline void audit_log_capset(const struct cred *new,
				   const struct cred *old)
{
	if (unlikely(!audit_dummy_context()))
		__audit_log_capset(new, old);
}

static inline void audit_mmap_fd(int fd, int flags)
{
	if (unlikely(!audit_dummy_context()))
		__audit_mmap_fd(fd, flags);
}

static inline void audit_openat2_how(struct open_how *how)
{
	if (unlikely(!audit_dummy_context()))
		__audit_openat2_how(how);
}

static inline void audit_log_kern_module(char *name)
{
	if (!audit_dummy_context())
		__audit_log_kern_module(name);
}

static inline void audit_fanotify(u32 response, struct fanotify_response_info_audit_rule *friar)
{
	if (!audit_dummy_context())
		__audit_fanotify(response, friar);
}

static inline void audit_tk_injoffset(struct timespec64 offset)
{
	/* ignore no-op events */
	if (offset.tv_sec == 0 && offset.tv_nsec == 0)
		return;

	if (!audit_dummy_context())
		__audit_tk_injoffset(offset);
}

static inline void audit_ntp_init(struct audit_ntp_data *ad)
{
	memset(ad, 0, sizeof(*ad));
}

static inline void audit_ntp_set_old(struct audit_ntp_data *ad,
				     enum audit_ntp_type type, long long val)
{
	ad->vals[type].oldval = val;
}

static inline void audit_ntp_set_new(struct audit_ntp_data *ad,
				     enum audit_ntp_type type, long long val)
{
	ad->vals[type].newval = val;
}

static inline void audit_ntp_log(const struct audit_ntp_data *ad)
{
	if (!audit_dummy_context())
		__audit_ntp_log(ad);
}

static inline void audit_log_nfcfg(const char *name, u8 af,
				   unsigned int nentries,
				   enum audit_nfcfgop op, gfp_t gfp)
{
	if (audit_enabled)
		__audit_log_nfcfg(name, af, nentries, op, gfp);
}

extern int audit_n_rules;
extern int audit_signals;
#else /* CONFIG_AUDITSYSCALL */
static inline int audit_alloc(struct task_struct *task)
{
	return 0;
}
static inline void audit_free(struct task_struct *task)
{ }
static inline void audit_uring_entry(u8 op)
{ }
static inline void audit_uring_exit(int success, long code)
{ }
static inline void audit_syscall_entry(int major, unsigned long a0,
				       unsigned long a1, unsigned long a2,
				       unsigned long a3)
{ }
static inline void audit_syscall_exit(void *pt_regs)
{ }
static inline bool audit_dummy_context(void)
{
	return true;
}
static inline void audit_set_context(struct task_struct *task, struct audit_context *ctx)
{ }
static inline struct audit_context *audit_context(void)
{
	return NULL;
}
static inline struct filename *audit_reusename(const __user char *name)
{
	return NULL;
}
static inline void audit_getname(struct filename *name)
{ }
static inline void audit_inode(struct filename *name,
				const struct dentry *dentry,
				unsigned int aflags)
{ }
static inline void audit_file(struct file *file)
{
}
static inline void audit_inode_parent_hidden(struct filename *name,
				const struct dentry *dentry)
{ }
static inline void audit_inode_child(struct inode *parent,
				     const struct dentry *dentry,
				     const unsigned char type)
{ }
static inline void audit_core_dumps(long signr)
{ }
static inline void audit_seccomp(unsigned long syscall, long signr, int code)
{ }
static inline void audit_seccomp_actions_logged(const char *names,
						const char *old_names, int res)
{ }
static inline void audit_ipc_obj(struct kern_ipc_perm *ipcp)
{ }
static inline void audit_ipc_set_perm(unsigned long qbytes, uid_t uid,
					gid_t gid, umode_t mode)
{ }
static inline void audit_bprm(struct linux_binprm *bprm)
{ }
static inline int audit_socketcall(int nargs, unsigned long *args)
{
	return 0;
}

static inline int audit_socketcall_compat(int nargs, u32 *args)
{
	return 0;
}

static inline void audit_fd_pair(int fd1, int fd2)
{ }
static inline int audit_sockaddr(int len, void *addr)
{
	return 0;
}
static inline void audit_mq_open(int oflag, umode_t mode, struct mq_attr *attr)
{ }
static inline void audit_mq_sendrecv(mqd_t mqdes, size_t msg_len,
				     unsigned int msg_prio,
				     const struct timespec64 *abs_timeout)
{ }
static inline void audit_mq_notify(mqd_t mqdes,
				   const struct sigevent *notification)
{ }
static inline void audit_mq_getsetattr(mqd_t mqdes, struct mq_attr *mqstat)
{ }
static inline int audit_log_bprm_fcaps(struct linux_binprm *bprm,
				       const struct cred *new,
				       const struct cred *old)
{
	return 0;
}
static inline void audit_log_capset(const struct cred *new,
				    const struct cred *old)
{ }
static inline void audit_mmap_fd(int fd, int flags)
{ }

static inline void audit_openat2_how(struct open_how *how)
{ }

static inline void audit_log_kern_module(char *name)
{
}

static inline void audit_fanotify(u32 response, struct fanotify_response_info_audit_rule *friar)
{ }

static inline void audit_tk_injoffset(struct timespec64 offset)
{ }

static inline void audit_ntp_init(struct audit_ntp_data *ad)
{ }

static inline void audit_ntp_set_old(struct audit_ntp_data *ad,
				     enum audit_ntp_type type, long long val)
{ }

static inline void audit_ntp_set_new(struct audit_ntp_data *ad,
				     enum audit_ntp_type type, long long val)
{ }

static inline void audit_ntp_log(const struct audit_ntp_data *ad)
{ }

static inline void audit_ptrace(struct task_struct *t)
{ }

static inline void audit_log_nfcfg(const char *name, u8 af,
				   unsigned int nentries,
				   enum audit_nfcfgop op, gfp_t gfp)
{ }

#define audit_n_rules 0
#define audit_signals 0
#endif /* CONFIG_AUDITSYSCALL */

static inline bool audit_loginuid_set(struct task_struct *tsk)
{
	return uid_valid(audit_get_loginuid(tsk));
}

#endif