/* SPDX-License-Identifier: GPL-2.0 */


#ifndef LINUX_LOCKD_LOCKD_H
#define LINUX_LOCKD_LOCKD_H



#include <linux/in.h>
#include <linux/in6.h>
#include <net/ipv6.h>
#include <linux/fs.h>
#include <linux/kref.h>
#include <linux/refcount.h>
#include <linux/utsname.h>
#include <linux/lockd/bind.h>
#include <linux/lockd/xdr.h>
#ifdef CONFIG_LOCKD_V4
#include <linux/lockd/xdr4.h>
#endif
#include <linux/lockd/debug.h>
#include <linux/sunrpc/svc.h>


#define LOCKD_VERSION		"0.5"


#define LOCKD_DFLT_TIMEO	10


struct nlm_host {
	struct hlist_node	h_hash;		
	struct sockaddr_storage	h_addr;		
	size_t			h_addrlen;
	struct sockaddr_storage	h_srcaddr;	
	size_t			h_srcaddrlen;
	struct rpc_clnt		*h_rpcclnt;	
	char			*h_name;		
	u32			h_version;	
	unsigned short		h_proto;	
	unsigned short		h_reclaiming : 1,
				h_server     : 1, 
				h_noresvport : 1,
				h_inuse      : 1;
	wait_queue_head_t	h_gracewait;	
	struct rw_semaphore	h_rwsem;	
	u32			h_state;	
	u32			h_nsmstate;	
	u32			h_pidcount;	
	refcount_t		h_count;	
	struct mutex		h_mutex;	
	unsigned long		h_nextrebind;	
	unsigned long		h_expires;	
	struct list_head	h_lockowners;	
	spinlock_t		h_lock;
	struct list_head	h_granted;	
	struct list_head	h_reclaim;	
	struct nsm_handle	*h_nsmhandle;	
	char			*h_addrbuf;	
	struct net		*net;		
	const struct cred	*h_cred;
	char			nodename[UNX_MAXNODENAME + 1];
	const struct nlmclnt_operations	*h_nlmclnt_ops;	
};


#define NSM_ADDRBUF		((8 * 4 + 7) + (1 + 10) + 1)

struct nsm_handle {
	struct list_head	sm_link;
	refcount_t		sm_count;
	char			*sm_mon_name;
	char			*sm_name;
	struct sockaddr_storage	sm_addr;
	size_t			sm_addrlen;
	unsigned int		sm_monitored : 1,
				sm_sticky : 1;	
	struct nsm_private	sm_priv;
	char			sm_addrbuf[NSM_ADDRBUF];
};


static inline struct sockaddr_in *nlm_addr_in(const struct nlm_host *host)
{
	return (struct sockaddr_in *)&host->h_addr;
}

static inline struct sockaddr *nlm_addr(const struct nlm_host *host)
{
	return (struct sockaddr *)&host->h_addr;
}

static inline struct sockaddr_in *nlm_srcaddr_in(const struct nlm_host *host)
{
	return (struct sockaddr_in *)&host->h_srcaddr;
}

static inline struct sockaddr *nlm_srcaddr(const struct nlm_host *host)
{
	return (struct sockaddr *)&host->h_srcaddr;
}


struct nlm_lockowner {
	struct list_head list;
	refcount_t count;

	struct nlm_host *host;
	fl_owner_t owner;
	uint32_t pid;
};

struct nlm_wait;


#define NLMCLNT_OHSIZE		((__NEW_UTS_LEN) + 10u)
struct nlm_rqst {
	refcount_t		a_count;
	unsigned int		a_flags;	
	struct nlm_host *	a_host;		
	struct nlm_args		a_args;		
	struct nlm_res		a_res;		
	struct nlm_block *	a_block;
	unsigned int		a_retries;	
	u8			a_owner[NLMCLNT_OHSIZE];
	void *	a_callback_data; 
};


struct nlm_file {
	struct hlist_node	f_list;		
	struct nfs_fh		f_handle;	
	struct file *		f_file[2];	
	struct nlm_share *	f_shares;	
	struct list_head	f_blocks;	
	unsigned int		f_locks;	
	unsigned int		f_count;	
	struct mutex		f_mutex;	
};


#define NLM_NEVER		(~(unsigned long) 0)

#define NLM_TIMEOUT		(7 * HZ)

struct nlm_block {
	struct kref		b_count;	
	struct list_head	b_list;		
	struct list_head	b_flist;	
	struct nlm_rqst	*	b_call;		
	struct svc_serv *	b_daemon;	
	struct nlm_host *	b_host;		
	unsigned long		b_when;		
	unsigned int		b_id;		
	unsigned char		b_granted;	
	struct nlm_file *	b_file;		
	struct cache_req *	b_cache_req;	
	struct cache_deferred_req * b_deferred_req;
	unsigned int		b_flags;	
#define B_QUEUED		1	
#define B_GOT_CALLBACK		2	
#define B_TIMED_OUT		4	
};


extern const struct rpc_program	nlm_program;
extern const struct svc_procedure nlmsvc_procedures[];
#ifdef CONFIG_LOCKD_V4
extern const struct svc_procedure nlmsvc_procedures4[];
#endif
extern int			nlmsvc_grace_period;
extern unsigned long		nlmsvc_timeout;
extern bool			nsm_use_hostnames;
extern u32			nsm_local_state;


struct nlm_rqst * nlm_alloc_call(struct nlm_host *host);
int		  nlm_async_call(struct nlm_rqst *, u32, const struct rpc_call_ops *);
int		  nlm_async_reply(struct nlm_rqst *, u32, const struct rpc_call_ops *);
void		  nlmclnt_release_call(struct nlm_rqst *);
struct nlm_wait * nlmclnt_prepare_block(struct nlm_host *host, struct file_lock *fl);
void		  nlmclnt_finish_block(struct nlm_wait *block);
int		  nlmclnt_block(struct nlm_wait *block, struct nlm_rqst *req, long timeout);
__be32		  nlmclnt_grant(const struct sockaddr *addr,
				const struct nlm_lock *lock);
void		  nlmclnt_recovery(struct nlm_host *);
int		  nlmclnt_reclaim(struct nlm_host *, struct file_lock *,
				  struct nlm_rqst *);
void		  nlmclnt_next_cookie(struct nlm_cookie *);


struct nlm_host  *nlmclnt_lookup_host(const struct sockaddr *sap,
					const size_t salen,
					const unsigned short protocol,
					const u32 version,
					const char *hostname,
					int noresvport,
					struct net *net,
					const struct cred *cred);
void		  nlmclnt_release_host(struct nlm_host *);
struct nlm_host  *nlmsvc_lookup_host(const struct svc_rqst *rqstp,
					const char *hostname,
					const size_t hostname_len);
void		  nlmsvc_release_host(struct nlm_host *);
struct rpc_clnt * nlm_bind_host(struct nlm_host *);
void		  nlm_rebind_host(struct nlm_host *);
struct nlm_host * nlm_get_host(struct nlm_host *);
void		  nlm_shutdown_hosts(void);
void		  nlm_shutdown_hosts_net(struct net *net);
void		  nlm_host_rebooted(const struct net *net,
					const struct nlm_reboot *);


int		  nsm_monitor(const struct nlm_host *host);
void		  nsm_unmonitor(const struct nlm_host *host);

struct nsm_handle *nsm_get_handle(const struct net *net,
					const struct sockaddr *sap,
					const size_t salen,
					const char *hostname,
					const size_t hostname_len);
struct nsm_handle *nsm_reboot_lookup(const struct net *net,
					const struct nlm_reboot *info);
void		  nsm_release(struct nsm_handle *nsm);


typedef int	  (*nlm_host_match_fn_t)(void *cur, struct nlm_host *ref);


int		  lock_to_openmode(struct file_lock *);
__be32		  nlmsvc_lock(struct svc_rqst *, struct nlm_file *,
			      struct nlm_host *, struct nlm_lock *, int,
			      struct nlm_cookie *, int);
__be32		  nlmsvc_unlock(struct net *net, struct nlm_file *, struct nlm_lock *);
__be32		  nlmsvc_testlock(struct svc_rqst *, struct nlm_file *,
			struct nlm_host *, struct nlm_lock *,
			struct nlm_lock *, struct nlm_cookie *);
__be32		  nlmsvc_cancel_blocked(struct net *net, struct nlm_file *, struct nlm_lock *);
unsigned long	  nlmsvc_retry_blocked(void);
void		  nlmsvc_traverse_blocks(struct nlm_host *, struct nlm_file *,
					nlm_host_match_fn_t match);
void		  nlmsvc_grant_reply(struct nlm_cookie *, __be32);
void		  nlmsvc_release_call(struct nlm_rqst *);
void		  nlmsvc_locks_init_private(struct file_lock *, struct nlm_host *, pid_t);


__be32		  nlm_lookup_file(struct svc_rqst *, struct nlm_file **,
					struct nlm_lock *);
void		  nlm_release_file(struct nlm_file *);
void		  nlmsvc_put_lockowner(struct nlm_lockowner *);
void		  nlmsvc_release_lockowner(struct nlm_lock *);
void		  nlmsvc_mark_resources(struct net *);
void		  nlmsvc_free_host_resources(struct nlm_host *);
void		  nlmsvc_invalidate_all(void);


int           nlmsvc_unlock_all_by_sb(struct super_block *sb);
int           nlmsvc_unlock_all_by_ip(struct sockaddr *server_addr);

static inline struct file *nlmsvc_file_file(struct nlm_file *file)
{
	return file->f_file[O_RDONLY] ?
	       file->f_file[O_RDONLY] : file->f_file[O_WRONLY];
}

static inline struct inode *nlmsvc_file_inode(struct nlm_file *file)
{
	return locks_inode(nlmsvc_file_file(file));
}

static inline int __nlm_privileged_request4(const struct sockaddr *sap)
{
	const struct sockaddr_in *sin = (struct sockaddr_in *)sap;

	if (ntohs(sin->sin_port) > 1023)
		return 0;

	return ipv4_is_loopback(sin->sin_addr.s_addr);
}

#if IS_ENABLED(CONFIG_IPV6)
static inline int __nlm_privileged_request6(const struct sockaddr *sap)
{
	const struct sockaddr_in6 *sin6 = (struct sockaddr_in6 *)sap;

	if (ntohs(sin6->sin6_port) > 1023)
		return 0;

	if (ipv6_addr_type(&sin6->sin6_addr) & IPV6_ADDR_MAPPED)
		return ipv4_is_loopback(sin6->sin6_addr.s6_addr32[3]);

	return ipv6_addr_type(&sin6->sin6_addr) & IPV6_ADDR_LOOPBACK;
}
#else	
static inline int __nlm_privileged_request6(const struct sockaddr *sap)
{
	return 0;
}
#endif	


static inline int nlm_privileged_requester(const struct svc_rqst *rqstp)
{
	const struct sockaddr *sap = svc_addr(rqstp);

	switch (sap->sa_family) {
	case AF_INET:
		return __nlm_privileged_request4(sap);
	case AF_INET6:
		return __nlm_privileged_request6(sap);
	default:
		return 0;
	}
}


static inline int nlm_compare_locks(const struct file_lock *fl1,
				    const struct file_lock *fl2)
{
	return locks_inode(fl1->fl_file) == locks_inode(fl2->fl_file)
	     && fl1->fl_pid   == fl2->fl_pid
	     && fl1->fl_owner == fl2->fl_owner
	     && fl1->fl_start == fl2->fl_start
	     && fl1->fl_end   == fl2->fl_end
	     &&(fl1->fl_type  == fl2->fl_type || fl2->fl_type == F_UNLCK);
}

extern const struct lock_manager_operations nlmsvc_lock_operations;

#endif 
