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
13struct module;
14
15struct 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_ctxt)(struct svc_xprt *xprt, void *ctxt);
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_handshake)(struct svc_xprt *xprt);
31};
32
33struct 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 */
47struct svc_xpt_user {
48 struct list_head list;
49 void (*callback)(struct svc_xpt_user *);
50};
51
52struct svc_xprt {
53 struct svc_xprt_class *xpt_class;
54 const struct svc_xprt_ops *xpt_ops;
55 struct kref xpt_ref;
56 ktime_t xpt_qtime;
57 struct list_head xpt_list;
58 struct lwq_node xpt_ready;
59 unsigned long xpt_flags;
60
61 struct svc_serv *xpt_server; /* service for transport */
62 atomic_t xpt_reserved; /* space on outq that is rsvd */
63 atomic_t xpt_nr_rqsts; /* Number of requests */
64 struct mutex xpt_mutex; /* to serialize sending data */
65 spinlock_t xpt_lock; /* protects sk_deferred
66 * and xpt_auth_cache */
67 void *xpt_auth_cache;/* auth cache */
68 struct list_head xpt_deferred; /* deferred requests that need
69 * to be revisted */
70 struct sockaddr_storage xpt_local; /* local address */
71 size_t xpt_locallen; /* length of address */
72 struct sockaddr_storage xpt_remote; /* remote peer's address */
73 size_t xpt_remotelen; /* length of address */
74 char xpt_remotebuf[INET6_ADDRSTRLEN + 10];
75 struct list_head xpt_users; /* callbacks on free */
76
77 struct net *xpt_net;
78 netns_tracker ns_tracker;
79 const struct cred *xpt_cred;
80 struct rpc_xprt *xpt_bc_xprt; /* NFSv4.1 backchannel */
81 struct rpc_xprt_switch *xpt_bc_xps; /* NFSv4.1 backchannel */
82};
83
84/* flag bits for xpt_flags */
85enum {
86 XPT_BUSY, /* enqueued/receiving */
87 XPT_CONN, /* conn pending */
88 XPT_CLOSE, /* dead or dying */
89 XPT_DATA, /* data pending */
90 XPT_TEMP, /* connected transport */
91 XPT_DEAD, /* transport closed */
92 XPT_CHNGBUF, /* need to change snd/rcv buf sizes */
93 XPT_DEFERRED, /* deferred request pending */
94 XPT_OLD, /* used for xprt aging mark+sweep */
95 XPT_LISTENER, /* listening endpoint */
96 XPT_CACHE_AUTH, /* cache auth info */
97 XPT_LOCAL, /* connection from loopback interface */
98 XPT_KILL_TEMP, /* call xpo_kill_temp_xprt before closing */
99 XPT_CONG_CTRL, /* has congestion control */
100 XPT_HANDSHAKE, /* xprt requests a handshake */
101 XPT_TLS_SESSION, /* transport-layer security established */
102 XPT_PEER_AUTH, /* peer has been authenticated */
103 XPT_PEER_VALID, /* peer has presented a filehandle that
104 * it has access to. It is NOT counted
105 * in ->sv_tmpcnt.
106 */
107 XPT_RPCB_UNREG, /* transport that needs unregistering
108 * with rpcbind (TCP, UDP) on destroy
109 */
110};
111
112/*
113 * Maximum number of "tmp" connections - those without XPT_PEER_VALID -
114 * permitted on any service.
115 */
116#define XPT_MAX_TMP_CONN 64
117
118static inline void svc_xprt_set_valid(struct svc_xprt *xpt)
119{
120 if (test_bit(XPT_TEMP, &xpt->xpt_flags) &&
121 !test_and_set_bit(nr: XPT_PEER_VALID, addr: &xpt->xpt_flags)) {
122 struct svc_serv *serv = xpt->xpt_server;
123
124 spin_lock(lock: &serv->sv_lock);
125 serv->sv_tmpcnt -= 1;
126 spin_unlock(lock: &serv->sv_lock);
127 }
128}
129
130static inline void unregister_xpt_user(struct svc_xprt *xpt, struct svc_xpt_user *u)
131{
132 spin_lock(lock: &xpt->xpt_lock);
133 list_del_init(entry: &u->list);
134 spin_unlock(lock: &xpt->xpt_lock);
135}
136
137static inline int register_xpt_user(struct svc_xprt *xpt, struct svc_xpt_user *u)
138{
139 spin_lock(lock: &xpt->xpt_lock);
140 if (test_bit(XPT_CLOSE, &xpt->xpt_flags)) {
141 /*
142 * The connection is about to be deleted soon (or,
143 * worse, may already be deleted--in which case we've
144 * already notified the xpt_users).
145 */
146 spin_unlock(lock: &xpt->xpt_lock);
147 return -ENOTCONN;
148 }
149 list_add(new: &u->list, head: &xpt->xpt_users);
150 spin_unlock(lock: &xpt->xpt_lock);
151 return 0;
152}
153
154static inline bool svc_xprt_is_dead(const struct svc_xprt *xprt)
155{
156 return (test_bit(XPT_DEAD, &xprt->xpt_flags) != 0) ||
157 (test_bit(XPT_CLOSE, &xprt->xpt_flags) != 0);
158}
159
160int svc_reg_xprt_class(struct svc_xprt_class *);
161void svc_unreg_xprt_class(struct svc_xprt_class *);
162void svc_xprt_init(struct net *, struct svc_xprt_class *, struct svc_xprt *,
163 struct svc_serv *);
164int svc_xprt_create_from_sa(struct svc_serv *serv, const char *xprt_name,
165 struct net *net, struct sockaddr *sap,
166 int flags, const struct cred *cred);
167int svc_xprt_create(struct svc_serv *serv, const char *xprt_name,
168 struct net *net, const int family,
169 const unsigned short port, int flags,
170 const struct cred *cred);
171void svc_xprt_destroy_all(struct svc_serv *serv, struct net *net,
172 bool unregister);
173void svc_xprt_received(struct svc_xprt *xprt);
174void svc_xprt_enqueue(struct svc_xprt *xprt);
175void svc_xprt_put(struct svc_xprt *xprt);
176void svc_xprt_copy_addrs(struct svc_rqst *rqstp, struct svc_xprt *xprt);
177void svc_xprt_close(struct svc_xprt *xprt);
178int svc_port_is_privileged(struct sockaddr *sin);
179int svc_print_xprts(char *buf, int maxlen);
180struct svc_xprt *svc_find_listener(struct svc_serv *serv, const char *xcl_name,
181 struct net *net, const struct sockaddr *sa);
182struct svc_xprt *svc_find_xprt(struct svc_serv *serv, const char *xcl_name,
183 struct net *net, const sa_family_t af,
184 const unsigned short port);
185int svc_xprt_names(struct svc_serv *serv, char *buf, const int buflen);
186void svc_add_new_perm_xprt(struct svc_serv *serv, struct svc_xprt *xprt);
187void svc_age_temp_xprts_now(struct svc_serv *, struct sockaddr *);
188void svc_xprt_deferred_close(struct svc_xprt *xprt);
189
190static inline void svc_xprt_get(struct svc_xprt *xprt)
191{
192 kref_get(kref: &xprt->xpt_ref);
193}
194static inline void svc_xprt_set_local(struct svc_xprt *xprt,
195 const struct sockaddr *sa,
196 const size_t salen)
197{
198 memcpy(to: &xprt->xpt_local, from: sa, len: salen);
199 xprt->xpt_locallen = salen;
200}
201static inline void svc_xprt_set_remote(struct svc_xprt *xprt,
202 const struct sockaddr *sa,
203 const size_t salen)
204{
205 memcpy(to: &xprt->xpt_remote, from: sa, len: salen);
206 xprt->xpt_remotelen = salen;
207 snprintf(buf: xprt->xpt_remotebuf, size: sizeof(xprt->xpt_remotebuf) - 1,
208 fmt: "%pISpc", sa);
209}
210
211static inline unsigned short svc_addr_port(const struct sockaddr *sa)
212{
213 const struct sockaddr_in *sin = (const struct sockaddr_in *)sa;
214 const struct sockaddr_in6 *sin6 = (const struct sockaddr_in6 *)sa;
215
216 switch (sa->sa_family) {
217 case AF_INET:
218 return ntohs(sin->sin_port);
219 case AF_INET6:
220 return ntohs(sin6->sin6_port);
221 }
222
223 return 0;
224}
225
226static inline size_t svc_addr_len(const struct sockaddr *sa)
227{
228 switch (sa->sa_family) {
229 case AF_INET:
230 return sizeof(struct sockaddr_in);
231 case AF_INET6:
232 return sizeof(struct sockaddr_in6);
233 }
234 BUG();
235}
236
237static inline unsigned short svc_xprt_local_port(const struct svc_xprt *xprt)
238{
239 return svc_addr_port(sa: (const struct sockaddr *)&xprt->xpt_local);
240}
241
242static inline unsigned short svc_xprt_remote_port(const struct svc_xprt *xprt)
243{
244 return svc_addr_port(sa: (const struct sockaddr *)&xprt->xpt_remote);
245}
246
247static inline char *__svc_print_addr(const struct sockaddr *addr,
248 char *buf, const size_t len)
249{
250 const struct sockaddr_in *sin = (const struct sockaddr_in *)addr;
251 const struct sockaddr_in6 *sin6 = (const struct sockaddr_in6 *)addr;
252
253 switch (addr->sa_family) {
254 case AF_INET:
255 snprintf(buf, size: len, fmt: "%pI4, port=%u", &sin->sin_addr,
256 ntohs(sin->sin_port));
257 break;
258
259 case AF_INET6:
260 snprintf(buf, size: len, fmt: "%pI6, port=%u",
261 &sin6->sin6_addr,
262 ntohs(sin6->sin6_port));
263 break;
264
265 default:
266 snprintf(buf, size: len, fmt: "unknown address type: %d", addr->sa_family);
267 break;
268 }
269
270 return buf;
271}
272#endif /* SUNRPC_SVC_XPRT_H */
273