lib/vconn-provider.h

   1 /*
   2  * Copyright (c) 2008, 2009, 2010, 2012, 2013 Nicira, Inc.
   3  *
   4  * Licensed under the Apache License, Version 2.0 (the "License");
   5  * you may not use this file except in compliance with the License.
   6  * You may obtain a copy of the License at:
   7  *
   8  *     http://www.apache.org/licenses/LICENSE-2.0
   9  *
  10  * Unless required by applicable law or agreed to in writing, software
  11  * distributed under the License is distributed on an "AS IS" BASIS,
  12  * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
  13  * See the License for the specific language governing permissions and
  14  * limitations under the License.
  15  */
  16
  17 #ifndef VCONN_PROVIDER_H
  18 #define VCONN_PROVIDER_H 1
  19
  20 /* Provider interface to vconns, which provide a virtual connection to an
  21  * OpenFlow device. */
  22
  23 #include "vconn.h"
  24 #include "util.h"
  25 #include "openflow/openflow-common.h"
  26 \f
  27 /* Active virtual connection to an OpenFlow device. */
  28
  29 /* Active virtual connection to an OpenFlow device.
  30  *
  31  * This structure should be treated as opaque by vconn implementations. */
  32 struct vconn {
  33     struct vconn_class *class;
  34     int state;
  35     int error;
  36
  37     /* OpenFlow versions. */
  38     uint32_t allowed_versions;  /* Bitmap of versions we will accept. */
  39     uint32_t peer_versions;     /* Peer's bitmap of versions it will accept. */
  40     enum ofp_version version;   /* Negotiated version (or 0). */
  41     bool recv_any_version;      /* True to receive a message of any version. */
  42
  43     ovs_be32 remote_ip;
  44     ovs_be16 remote_port;
  45     ovs_be32 local_ip;
  46     ovs_be16 local_port;
  47
  48     char *name;
  49 };
  50
  51 void vconn_init(struct vconn *, struct vconn_class *, int connect_status,
  52                 const char *name, uint32_t allowed_versions);
  53 void vconn_free_data(struct vconn *vconn);
  54 void vconn_set_remote_ip(struct vconn *, ovs_be32 remote_ip);
  55 void vconn_set_remote_port(struct vconn *, ovs_be16 remote_port);
  56 void vconn_set_local_ip(struct vconn *, ovs_be32 local_ip);
  57 void vconn_set_local_port(struct vconn *, ovs_be16 local_port);
  58 static inline void vconn_assert_class(const struct vconn *vconn,
  59                                       const struct vconn_class *class)
  60 {
  61     ovs_assert(vconn->class == class);
  62 }
  63
  64 struct vconn_class {
  65     /* Prefix for connection names, e.g. "nl", "tcp". */
  66     const char *name;
  67
  68     /* Attempts to connect to an OpenFlow device.  'name' is the full
  69      * connection name provided by the user, e.g. "tcp:1.2.3.4".  This name is
  70      * useful for error messages but must not be modified.
  71      *
  72      * 'allowed_verions' is the OpenFlow versions that may be
  73      * negotiated for a connection.
  74      *
  75      * 'suffix' is a copy of 'name' following the colon and may be modified.
  76      * 'dscp' is the DSCP value that the new connection should use in the IP
  77      * packets it sends.
  78      *
  79      * Returns 0 if successful, otherwise a positive errno value.  If
  80      * successful, stores a pointer to the new connection in '*vconnp'.
  81      *
  82      * The open function must not block waiting for a connection to complete.
  83      * If the connection cannot be completed immediately, it should return
  84      * EAGAIN (not EINPROGRESS, as returned by the connect system call) and
  85      * continue the connection in the background. */
  86     int (*open)(const char *name, uint32_t allowed_versions,
  87                 char *suffix, struct vconn **vconnp, uint8_t dscp);
  88
  89     /* Closes 'vconn' and frees associated memory. */
  90     void (*close)(struct vconn *vconn);
  91
  92     /* Tries to complete the connection on 'vconn'.  If 'vconn''s connection is
  93      * complete, returns 0 if the connection was successful or a positive errno
  94      * value if it failed.  If the connection is still in progress, returns
  95      * EAGAIN.
  96      *
  97      * The connect function must not block waiting for the connection to
  98      * complete; instead, it should return EAGAIN immediately. */
  99     int (*connect)(struct vconn *vconn);
 100
 101     /* Tries to receive an OpenFlow message from 'vconn'.  If successful,
 102      * stores the received message into '*msgp' and returns 0.  The caller is
 103      * responsible for destroying the message with ofpbuf_delete().  On
 104      * failure, returns a positive errno value and stores a null pointer into
 105      * '*msgp'.
 106      *
 107      * If the connection has been closed in the normal fashion, returns EOF.
 108      *
 109      * The recv function must not block waiting for a packet to arrive.  If no
 110      * packets have been received, it should return EAGAIN. */
 111     int (*recv)(struct vconn *vconn, struct ofpbuf **msgp);
 112
 113     /* Tries to queue 'msg' for transmission on 'vconn'.  If successful,
 114      * returns 0, in which case ownership of 'msg' is transferred to the vconn.
 115      * Success does not guarantee that 'msg' has been or ever will be delivered
 116      * to the peer, only that it has been queued for transmission.
 117      *
 118      * Returns a positive errno value on failure, in which case the caller
 119      * retains ownership of 'msg'.
 120      *
 121      * The send function must not block.  If 'msg' cannot be immediately
 122      * accepted for transmission, it should return EAGAIN. */
 123     int (*send)(struct vconn *vconn, struct ofpbuf *msg);
 124
 125     /* Allows 'vconn' to perform maintenance activities, such as flushing
 126      * output buffers.
 127      *
 128      * May be null if 'vconn' doesn't have anything to do here. */
 129     void (*run)(struct vconn *vconn);
 130
 131     /* Arranges for the poll loop to wake up when 'vconn' needs to perform
 132      * maintenance activities.
 133      *
 134      * May be null if 'vconn' doesn't have anything to do here. */
 135     void (*run_wait)(struct vconn *vconn);
 136
 137     /* Arranges for the poll loop to wake up when 'vconn' is ready to take an
 138      * action of the given 'type'. */
 139     void (*wait)(struct vconn *vconn, enum vconn_wait_type type);
 140 };
 141 \f
 142 /* Passive virtual connection to an OpenFlow device.
 143  *
 144  * This structure should be treated as opaque by vconn implementations. */
 145 struct pvconn {
 146     struct pvconn_class *class;
 147     char *name;
 148     uint32_t allowed_versions;
 149 };
 150
 151 void pvconn_init(struct pvconn *pvconn, struct pvconn_class *class,
 152                  const char *name, uint32_t allowed_versions);
 153 static inline void pvconn_assert_class(const struct pvconn *pvconn,
 154                                        const struct pvconn_class *class)
 155 {
 156     ovs_assert(pvconn->class == class);
 157 }
 158
 159 struct pvconn_class {
 160     /* Prefix for connection names, e.g. "ptcp", "pssl". */
 161     const char *name;
 162
 163     /* Attempts to start listening for OpenFlow connections.  'name' is the
 164      * full connection name provided by the user, e.g. "ptcp:1234".  This name
 165      * is useful for error messages but must not be modified.
 166      *
 167      * 'allowed_versions' is the OpenFlow protocol versions that may
 168      * be negotiated for a session.
 169      *
 170      * 'suffix' is a copy of 'name' following the colon and may be modified.
 171      * 'dscp' is the DSCP value that the new connection should use in the IP
 172      * packets it sends.
 173      *
 174      * Returns 0 if successful, otherwise a positive errno value.  If
 175      * successful, stores a pointer to the new connection in '*pvconnp'.
 176      *
 177      * The listen function must not block.  If the connection cannot be
 178      * completed immediately, it should return EAGAIN (not EINPROGRESS, as
 179      * returned by the connect system call) and continue the connection in the
 180      * background. */
 181     int (*listen)(const char *name, uint32_t allowed_versions,
 182                   char *suffix, struct pvconn **pvconnp, uint8_t dscp);
 183
 184     /* Closes 'pvconn' and frees associated memory. */
 185     void (*close)(struct pvconn *pvconn);
 186
 187     /* Tries to accept a new connection on 'pvconn'.  If successful, stores the
 188      * new connection in '*new_vconnp' and returns 0.  Otherwise, returns a
 189      * positive errno value.
 190      *
 191      * The accept function must not block waiting for a connection.  If no
 192      * connection is ready to be accepted, it should return EAGAIN. */
 193     int (*accept)(struct pvconn *pvconn, struct vconn **new_vconnp);
 194
 195     /* Arranges for the poll loop to wake up when a connection is ready to be
 196      * accepted on 'pvconn'. */
 197     void (*wait)(struct pvconn *pvconn);
 198 };
 199
 200 /* Active and passive vconn classes. */
 201 extern struct vconn_class tcp_vconn_class;
 202 extern struct pvconn_class ptcp_pvconn_class;
 203 extern struct vconn_class unix_vconn_class;
 204 extern struct pvconn_class punix_pvconn_class;
 205 #ifdef HAVE_OPENSSL
 206 extern struct vconn_class ssl_vconn_class;
 207 extern struct pvconn_class pssl_pvconn_class;
 208 #endif
 209
 210 #endif /* vconn-provider.h */