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_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
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 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 */
85 enum {
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 };
108
109 /*
110 * Maximum number of "tmp" connections - those without XPT_PEER_VALID -
111 * permitted on any service.
112 */
113 #define XPT_MAX_TMP_CONN 64
114
svc_xprt_set_valid(struct svc_xprt * xpt)115 static inline void svc_xprt_set_valid(struct svc_xprt *xpt)
116 {
117 if (test_bit(XPT_TEMP, &xpt->xpt_flags) &&
118 !test_and_set_bit(XPT_PEER_VALID, &xpt->xpt_flags)) {
119 struct svc_serv *serv = xpt->xpt_server;
120
121 spin_lock(&serv->sv_lock);
122 serv->sv_tmpcnt -= 1;
123 spin_unlock(&serv->sv_lock);
124 }
125 }
126
unregister_xpt_user(struct svc_xprt * xpt,struct svc_xpt_user * u)127 static inline void unregister_xpt_user(struct svc_xprt *xpt, struct svc_xpt_user *u)
128 {
129 spin_lock(&xpt->xpt_lock);
130 list_del_init(&u->list);
131 spin_unlock(&xpt->xpt_lock);
132 }
133
register_xpt_user(struct svc_xprt * xpt,struct svc_xpt_user * u)134 static inline int register_xpt_user(struct svc_xprt *xpt, struct svc_xpt_user *u)
135 {
136 spin_lock(&xpt->xpt_lock);
137 if (test_bit(XPT_CLOSE, &xpt->xpt_flags)) {
138 /*
139 * The connection is about to be deleted soon (or,
140 * worse, may already be deleted--in which case we've
141 * already notified the xpt_users).
142 */
143 spin_unlock(&xpt->xpt_lock);
144 return -ENOTCONN;
145 }
146 list_add(&u->list, &xpt->xpt_users);
147 spin_unlock(&xpt->xpt_lock);
148 return 0;
149 }
150
svc_xprt_is_dead(const struct svc_xprt * xprt)151 static inline bool svc_xprt_is_dead(const struct svc_xprt *xprt)
152 {
153 return (test_bit(XPT_DEAD, &xprt->xpt_flags) != 0) ||
154 (test_bit(XPT_CLOSE, &xprt->xpt_flags) != 0);
155 }
156
157 int svc_reg_xprt_class(struct svc_xprt_class *);
158 void svc_unreg_xprt_class(struct svc_xprt_class *);
159 void svc_xprt_init(struct net *, struct svc_xprt_class *, struct svc_xprt *,
160 struct svc_serv *);
161 int svc_xprt_create_from_sa(struct svc_serv *serv, const char *xprt_name,
162 struct net *net, struct sockaddr *sap,
163 int flags, const struct cred *cred);
164 int svc_xprt_create(struct svc_serv *serv, const char *xprt_name,
165 struct net *net, const int family,
166 const unsigned short port, int flags,
167 const struct cred *cred);
168 void svc_xprt_destroy_all(struct svc_serv *serv, struct net *net,
169 bool unregister);
170 void svc_xprt_received(struct svc_xprt *xprt);
171 void svc_xprt_enqueue(struct svc_xprt *xprt);
172 void svc_xprt_put(struct svc_xprt *xprt);
173 void svc_xprt_copy_addrs(struct svc_rqst *rqstp, struct svc_xprt *xprt);
174 void svc_xprt_close(struct svc_xprt *xprt);
175 int svc_port_is_privileged(struct sockaddr *sin);
176 int svc_print_xprts(char *buf, int maxlen);
177 struct svc_xprt *svc_find_listener(struct svc_serv *serv, const char *xcl_name,
178 struct net *net, const struct sockaddr *sa);
179 struct svc_xprt *svc_find_xprt(struct svc_serv *serv, const char *xcl_name,
180 struct net *net, const sa_family_t af,
181 const unsigned short port);
182 int svc_xprt_names(struct svc_serv *serv, char *buf, const int buflen);
183 void svc_add_new_perm_xprt(struct svc_serv *serv, struct svc_xprt *xprt);
184 void svc_age_temp_xprts_now(struct svc_serv *, struct sockaddr *);
185 void svc_xprt_deferred_close(struct svc_xprt *xprt);
186
svc_xprt_get(struct svc_xprt * xprt)187 static inline void svc_xprt_get(struct svc_xprt *xprt)
188 {
189 kref_get(&xprt->xpt_ref);
190 }
svc_xprt_set_local(struct svc_xprt * xprt,const struct sockaddr * sa,const size_t salen)191 static inline void svc_xprt_set_local(struct svc_xprt *xprt,
192 const struct sockaddr *sa,
193 const size_t salen)
194 {
195 memcpy(&xprt->xpt_local, sa, salen);
196 xprt->xpt_locallen = salen;
197 }
svc_xprt_set_remote(struct svc_xprt * xprt,const struct sockaddr * sa,const size_t salen)198 static inline void svc_xprt_set_remote(struct svc_xprt *xprt,
199 const struct sockaddr *sa,
200 const size_t salen)
201 {
202 memcpy(&xprt->xpt_remote, sa, salen);
203 xprt->xpt_remotelen = salen;
204 snprintf(xprt->xpt_remotebuf, sizeof(xprt->xpt_remotebuf) - 1,
205 "%pISpc", sa);
206 }
207
svc_addr_port(const struct sockaddr * sa)208 static inline unsigned short svc_addr_port(const struct sockaddr *sa)
209 {
210 const struct sockaddr_in *sin = (const struct sockaddr_in *)sa;
211 const struct sockaddr_in6 *sin6 = (const struct sockaddr_in6 *)sa;
212
213 switch (sa->sa_family) {
214 case AF_INET:
215 return ntohs(sin->sin_port);
216 case AF_INET6:
217 return ntohs(sin6->sin6_port);
218 }
219
220 return 0;
221 }
222
svc_addr_len(const struct sockaddr * sa)223 static inline size_t svc_addr_len(const struct sockaddr *sa)
224 {
225 switch (sa->sa_family) {
226 case AF_INET:
227 return sizeof(struct sockaddr_in);
228 case AF_INET6:
229 return sizeof(struct sockaddr_in6);
230 }
231 BUG();
232 }
233
svc_xprt_local_port(const struct svc_xprt * xprt)234 static inline unsigned short svc_xprt_local_port(const struct svc_xprt *xprt)
235 {
236 return svc_addr_port((const struct sockaddr *)&xprt->xpt_local);
237 }
238
svc_xprt_remote_port(const struct svc_xprt * xprt)239 static inline unsigned short svc_xprt_remote_port(const struct svc_xprt *xprt)
240 {
241 return svc_addr_port((const struct sockaddr *)&xprt->xpt_remote);
242 }
243
__svc_print_addr(const struct sockaddr * addr,char * buf,const size_t len)244 static inline char *__svc_print_addr(const struct sockaddr *addr,
245 char *buf, const size_t len)
246 {
247 const struct sockaddr_in *sin = (const struct sockaddr_in *)addr;
248 const struct sockaddr_in6 *sin6 = (const struct sockaddr_in6 *)addr;
249
250 switch (addr->sa_family) {
251 case AF_INET:
252 snprintf(buf, len, "%pI4, port=%u", &sin->sin_addr,
253 ntohs(sin->sin_port));
254 break;
255
256 case AF_INET6:
257 snprintf(buf, len, "%pI6, port=%u",
258 &sin6->sin6_addr,
259 ntohs(sin6->sin6_port));
260 break;
261
262 default:
263 snprintf(buf, len, "unknown address type: %d", addr->sa_family);
264 break;
265 }
266
267 return buf;
268 }
269 #endif /* SUNRPC_SVC_XPRT_H */
270