1  /* SPDX-License-Identifier: GPL-2.0 */
2  /*
3   * linux/include/linux/sunrpc/svc_xprt.h
4   *
5   * RPC server transport I/O
6   */
7  
8  #ifndef SUNRPC_SVC_XPRT_H
9  #define SUNRPC_SVC_XPRT_H
10  
11  #include <linux/sunrpc/svc.h>
12  
13  struct module;
14  
15  struct svc_xprt_ops {
16  	struct svc_xprt	*(*xpo_create)(struct svc_serv *,
17  				       struct net *net,
18  				       struct sockaddr *, int,
19  				       int);
20  	struct svc_xprt	*(*xpo_accept)(struct svc_xprt *);
21  	int		(*xpo_has_wspace)(struct svc_xprt *);
22  	int		(*xpo_recvfrom)(struct svc_rqst *);
23  	int		(*xpo_sendto)(struct svc_rqst *);
24  	int		(*xpo_result_payload)(struct svc_rqst *, unsigned int,
25  					      unsigned int);
26  	void		(*xpo_release_rqst)(struct svc_rqst *);
27  	void		(*xpo_detach)(struct svc_xprt *);
28  	void		(*xpo_free)(struct svc_xprt *);
29  	void		(*xpo_kill_temp_xprt)(struct svc_xprt *);
30  	void		(*xpo_start_tls)(struct svc_xprt *);
31  };
32  
33  struct svc_xprt_class {
34  	const char		*xcl_name;
35  	struct module		*xcl_owner;
36  	const struct svc_xprt_ops *xcl_ops;
37  	struct list_head	xcl_list;
38  	u32			xcl_max_payload;
39  	int			xcl_ident;
40  };
41  
42  /*
43   * This is embedded in an object that wants a callback before deleting
44   * an xprt; intended for use by NFSv4.1, which needs to know when a
45   * client's tcp connection (and hence possibly a backchannel) goes away.
46   */
47  struct svc_xpt_user {
48  	struct list_head list;
49  	void (*callback)(struct svc_xpt_user *);
50  };
51  
52  struct svc_xprt {
53  	struct svc_xprt_class	*xpt_class;
54  	const struct svc_xprt_ops *xpt_ops;
55  	struct kref		xpt_ref;
56  	struct list_head	xpt_list;
57  	struct list_head	xpt_ready;
58  	unsigned long		xpt_flags;
59  #define	XPT_BUSY	0		/* enqueued/receiving */
60  #define	XPT_CONN	1		/* conn pending */
61  #define	XPT_CLOSE	2		/* dead or dying */
62  #define	XPT_DATA	3		/* data pending */
63  #define	XPT_TEMP	4		/* connected transport */
64  #define	XPT_DEAD	6		/* transport closed */
65  #define	XPT_CHNGBUF	7		/* need to change snd/rcv buf sizes */
66  #define	XPT_DEFERRED	8		/* deferred request pending */
67  #define	XPT_OLD		9		/* used for xprt aging mark+sweep */
68  #define XPT_LISTENER	10		/* listening endpoint */
69  #define XPT_CACHE_AUTH	11		/* cache auth info */
70  #define XPT_LOCAL	12		/* connection from loopback interface */
71  #define XPT_KILL_TEMP   13		/* call xpo_kill_temp_xprt before closing */
72  #define XPT_CONG_CTRL	14		/* has congestion control */
73  
74  	struct svc_serv		*xpt_server;	/* service for transport */
75  	atomic_t    	    	xpt_reserved;	/* space on outq that is rsvd */
76  	atomic_t		xpt_nr_rqsts;	/* Number of requests */
77  	struct mutex		xpt_mutex;	/* to serialize sending data */
78  	spinlock_t		xpt_lock;	/* protects sk_deferred
79  						 * and xpt_auth_cache */
80  	void			*xpt_auth_cache;/* auth cache */
81  	struct list_head	xpt_deferred;	/* deferred requests that need
82  						 * to be revisted */
83  	struct sockaddr_storage	xpt_local;	/* local address */
84  	size_t			xpt_locallen;	/* length of address */
85  	struct sockaddr_storage	xpt_remote;	/* remote peer's address */
86  	size_t			xpt_remotelen;	/* length of address */
87  	char			xpt_remotebuf[INET6_ADDRSTRLEN + 10];
88  	struct list_head	xpt_users;	/* callbacks on free */
89  
90  	struct net		*xpt_net;
91  	netns_tracker		ns_tracker;
92  	const struct cred	*xpt_cred;
93  	struct rpc_xprt		*xpt_bc_xprt;	/* NFSv4.1 backchannel */
94  	struct rpc_xprt_switch	*xpt_bc_xps;	/* NFSv4.1 backchannel */
95  };
96  
unregister_xpt_user(struct svc_xprt * xpt,struct svc_xpt_user * u)97  static inline void unregister_xpt_user(struct svc_xprt *xpt, struct svc_xpt_user *u)
98  {
99  	spin_lock(&xpt->xpt_lock);
100  	list_del_init(&u->list);
101  	spin_unlock(&xpt->xpt_lock);
102  }
103  
register_xpt_user(struct svc_xprt * xpt,struct svc_xpt_user * u)104  static inline int register_xpt_user(struct svc_xprt *xpt, struct svc_xpt_user *u)
105  {
106  	spin_lock(&xpt->xpt_lock);
107  	if (test_bit(XPT_CLOSE, &xpt->xpt_flags)) {
108  		/*
109  		 * The connection is about to be deleted soon (or,
110  		 * worse, may already be deleted--in which case we've
111  		 * already notified the xpt_users).
112  		 */
113  		spin_unlock(&xpt->xpt_lock);
114  		return -ENOTCONN;
115  	}
116  	list_add(&u->list, &xpt->xpt_users);
117  	spin_unlock(&xpt->xpt_lock);
118  	return 0;
119  }
120  
svc_xprt_is_dead(const struct svc_xprt * xprt)121  static inline bool svc_xprt_is_dead(const struct svc_xprt *xprt)
122  {
123  	return (test_bit(XPT_DEAD, &xprt->xpt_flags) != 0) ||
124  		(test_bit(XPT_CLOSE, &xprt->xpt_flags) != 0);
125  }
126  
127  int	svc_reg_xprt_class(struct svc_xprt_class *);
128  void	svc_unreg_xprt_class(struct svc_xprt_class *);
129  void	svc_xprt_init(struct net *, struct svc_xprt_class *, struct svc_xprt *,
130  		      struct svc_serv *);
131  int	svc_xprt_create(struct svc_serv *serv, const char *xprt_name,
132  			struct net *net, const int family,
133  			const unsigned short port, int flags,
134  			const struct cred *cred);
135  void	svc_xprt_destroy_all(struct svc_serv *serv, struct net *net);
136  void	svc_xprt_received(struct svc_xprt *xprt);
137  void	svc_xprt_enqueue(struct svc_xprt *xprt);
138  void	svc_xprt_put(struct svc_xprt *xprt);
139  void	svc_xprt_copy_addrs(struct svc_rqst *rqstp, struct svc_xprt *xprt);
140  void	svc_xprt_close(struct svc_xprt *xprt);
141  int	svc_port_is_privileged(struct sockaddr *sin);
142  int	svc_print_xprts(char *buf, int maxlen);
143  struct	svc_xprt *svc_find_xprt(struct svc_serv *serv, const char *xcl_name,
144  			struct net *net, const sa_family_t af,
145  			const unsigned short port);
146  int	svc_xprt_names(struct svc_serv *serv, char *buf, const int buflen);
147  void	svc_add_new_perm_xprt(struct svc_serv *serv, struct svc_xprt *xprt);
148  void	svc_age_temp_xprts_now(struct svc_serv *, struct sockaddr *);
149  void	svc_xprt_deferred_close(struct svc_xprt *xprt);
150  
svc_xprt_get(struct svc_xprt * xprt)151  static inline void svc_xprt_get(struct svc_xprt *xprt)
152  {
153  	kref_get(&xprt->xpt_ref);
154  }
svc_xprt_set_local(struct svc_xprt * xprt,const struct sockaddr * sa,const size_t salen)155  static inline void svc_xprt_set_local(struct svc_xprt *xprt,
156  				      const struct sockaddr *sa,
157  				      const size_t salen)
158  {
159  	memcpy(&xprt->xpt_local, sa, salen);
160  	xprt->xpt_locallen = salen;
161  }
svc_xprt_set_remote(struct svc_xprt * xprt,const struct sockaddr * sa,const size_t salen)162  static inline void svc_xprt_set_remote(struct svc_xprt *xprt,
163  				       const struct sockaddr *sa,
164  				       const size_t salen)
165  {
166  	memcpy(&xprt->xpt_remote, sa, salen);
167  	xprt->xpt_remotelen = salen;
168  	snprintf(xprt->xpt_remotebuf, sizeof(xprt->xpt_remotebuf) - 1,
169  		 "%pISpc", sa);
170  }
171  
svc_addr_port(const struct sockaddr * sa)172  static inline unsigned short svc_addr_port(const struct sockaddr *sa)
173  {
174  	const struct sockaddr_in *sin = (const struct sockaddr_in *)sa;
175  	const struct sockaddr_in6 *sin6 = (const struct sockaddr_in6 *)sa;
176  
177  	switch (sa->sa_family) {
178  	case AF_INET:
179  		return ntohs(sin->sin_port);
180  	case AF_INET6:
181  		return ntohs(sin6->sin6_port);
182  	}
183  
184  	return 0;
185  }
186  
svc_addr_len(const struct sockaddr * sa)187  static inline size_t svc_addr_len(const struct sockaddr *sa)
188  {
189  	switch (sa->sa_family) {
190  	case AF_INET:
191  		return sizeof(struct sockaddr_in);
192  	case AF_INET6:
193  		return sizeof(struct sockaddr_in6);
194  	}
195  	BUG();
196  }
197  
svc_xprt_local_port(const struct svc_xprt * xprt)198  static inline unsigned short svc_xprt_local_port(const struct svc_xprt *xprt)
199  {
200  	return svc_addr_port((const struct sockaddr *)&xprt->xpt_local);
201  }
202  
svc_xprt_remote_port(const struct svc_xprt * xprt)203  static inline unsigned short svc_xprt_remote_port(const struct svc_xprt *xprt)
204  {
205  	return svc_addr_port((const struct sockaddr *)&xprt->xpt_remote);
206  }
207  
__svc_print_addr(const struct sockaddr * addr,char * buf,const size_t len)208  static inline char *__svc_print_addr(const struct sockaddr *addr,
209  				     char *buf, const size_t len)
210  {
211  	const struct sockaddr_in *sin = (const struct sockaddr_in *)addr;
212  	const struct sockaddr_in6 *sin6 = (const struct sockaddr_in6 *)addr;
213  
214  	switch (addr->sa_family) {
215  	case AF_INET:
216  		snprintf(buf, len, "%pI4, port=%u", &sin->sin_addr,
217  			ntohs(sin->sin_port));
218  		break;
219  
220  	case AF_INET6:
221  		snprintf(buf, len, "%pI6, port=%u",
222  			 &sin6->sin6_addr,
223  			ntohs(sin6->sin6_port));
224  		break;
225  
226  	default:
227  		snprintf(buf, len, "unknown address type: %d", addr->sa_family);
228  		break;
229  	}
230  
231  	return buf;
232  }
233  #endif /* SUNRPC_SVC_XPRT_H */
234