2 * Copyright (c) 2009, 2010 Nicira Networks.
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:
8 * http://www.apache.org/licenses/LICENSE-2.0
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.
17 #ifndef NETDEV_PROVIDER_H
18 #define NETDEV_PROVIDER_H 1
20 /* Generic interface to network devices. */
33 /* A network device (e.g. an Ethernet device).
35 * This structure should be treated as opaque by network device
38 char *name; /* Name of network device. */
39 const struct netdev_class *class; /* Functions to control this device. */
40 int ref_cnt; /* Times this devices was opened. */
41 struct shash_node *node; /* Pointer to element in global map. */
42 struct arg *args; /* Argument list from last config. */
43 int n_args; /* Number of arguments in 'args'. */
46 void netdev_dev_init(struct netdev_dev *, const char *name,
47 const struct netdev_class *);
48 void netdev_dev_uninit(struct netdev_dev *, bool destroy);
49 const char *netdev_dev_get_type(const struct netdev_dev *);
50 const char *netdev_dev_get_name(const struct netdev_dev *);
51 struct netdev_dev *netdev_dev_from_name(const char *name);
52 void netdev_dev_get_devices(const struct netdev_class *,
53 struct shash *device_list);
55 static inline void netdev_dev_assert_class(const struct netdev_dev *netdev_dev,
56 const struct netdev_class *class)
58 assert(netdev_dev->class == class);
61 /* A instance of an open network device.
63 * This structure should be treated as opaque by network device
66 struct netdev_dev *netdev_dev; /* Parent netdev_dev. */
67 struct list node; /* Element in global list. */
69 enum netdev_flags save_flags; /* Initial device flags. */
70 enum netdev_flags changed_flags; /* Flags that we changed. */
73 void netdev_init(struct netdev *, struct netdev_dev *);
74 void netdev_uninit(struct netdev *, bool close);
75 struct netdev_dev *netdev_get_dev(const struct netdev *);
77 static inline void netdev_assert_class(const struct netdev *netdev,
78 const struct netdev_class *class)
80 netdev_dev_assert_class(netdev_get_dev(netdev), class);
83 /* A network device notifier.
85 * Network device implementations should use netdev_notifier_init() to
86 * initialize this structure, but they may freely read its members after
88 struct netdev_notifier {
89 struct netdev *netdev;
90 void (*cb)(struct netdev_notifier *);
93 void netdev_notifier_init(struct netdev_notifier *, struct netdev *,
94 void (*cb)(struct netdev_notifier *), void *aux);
96 /* Network device class structure, to be defined by each implementation of a
99 * These functions return 0 if successful or a positive errno value on failure,
100 * except where otherwise noted. */
101 struct netdev_class {
102 /* Type of netdevs in this class, e.g. "system", "tap", "gre", etc.
104 * One of the providers should supply a "system" type, since this is
105 * the type assumed if no type is specified when opening a netdev.
106 * The "system" type corresponds to an existing network device on
110 /* Called only once, at program startup. Returning an error from this
111 * function will prevent any network device in this class from being
114 * This function may be set to null if a network device class needs no
115 * initialization at program startup. */
118 /* Performs periodic work needed by netdevs of this class. May be null if
119 * no periodic work is necessary. */
122 /* Arranges for poll_block() to wake up if the "run" member function needs
123 * to be called. May be null if nothing is needed here. */
126 /* Attempts to create a network device of 'type' with 'name'.
127 * 'type' corresponds to the 'type' field used in the netdev_class
128 * structure. On success sets 'netdev_devp' to the newly created device. */
129 int (*create)(const char *name, const char *type, const struct shash *args,
130 struct netdev_dev **netdev_devp);
132 /* Destroys 'netdev_dev'.
134 * Netdev devices maintain a reference count that is incremented on
135 * netdev_open() and decremented on netdev_close(). If 'netdev_dev'
136 * has a non-zero reference count, then this function will not be
138 void (*destroy)(struct netdev_dev *netdev_dev);
140 /* Reconfigures the device 'netdev_dev' with 'args'.
142 * If this netdev class does not support reconfiguring a netdev
143 * device, this may be a null pointer.
145 int (*reconfigure)(struct netdev_dev *netdev_dev, const struct shash *args);
147 /* Attempts to open a network device. On success, sets 'netdevp'
148 * to the new network device.
150 * 'ethertype' may be a 16-bit Ethernet protocol value in host byte order
151 * to capture frames of that type received on the device. It may also be
152 * one of the 'enum netdev_pseudo_ethertype' values to receive frames in
153 * one of those categories. */
154 int (*open)(struct netdev_dev *netdev_dev, int ethertype,
155 struct netdev **netdevp);
157 /* Closes 'netdev'. */
158 void (*close)(struct netdev *netdev);
160 /* Enumerates the names of all network devices of this class.
162 * The caller has already initialized 'all_names' and might already have
163 * added some names to it. This function should not disturb any existing
164 * names in 'all_names'.
166 * If this netdev class does not support enumeration, this may be a null
168 int (*enumerate)(struct svec *all_names);
170 /* Attempts to receive a packet from 'netdev' into the 'size' bytes in
171 * 'buffer'. If successful, returns the number of bytes in the received
172 * packet, otherwise a negative errno value. Returns -EAGAIN immediately
173 * if no packet is ready to be received. */
174 int (*recv)(struct netdev *netdev, void *buffer, size_t size);
176 /* Registers with the poll loop to wake up from the next call to
177 * poll_block() when a packet is ready to be received with netdev_recv() on
179 void (*recv_wait)(struct netdev *netdev);
181 /* Discards all packets waiting to be received from 'netdev'. */
182 int (*drain)(struct netdev *netdev);
184 /* Sends the 'size'-byte packet in 'buffer' on 'netdev'. Returns 0 if
185 * successful, otherwise a positive errno value. Returns EAGAIN without
186 * blocking if the packet cannot be queued immediately. Returns EMSGSIZE
187 * if a partial packet was transmitted or if the packet is too big or too
188 * small to transmit on the device.
190 * The caller retains ownership of 'buffer' in all cases.
192 * The network device is expected to maintain a packet transmission queue,
193 * so that the caller does not ordinarily have to do additional queuing of
195 int (*send)(struct netdev *netdev, const void *buffer, size_t size);
197 /* Registers with the poll loop to wake up from the next call to
198 * poll_block() when the packet transmission queue for 'netdev' has
199 * sufficient room to transmit a packet with netdev_send().
201 * The network device is expected to maintain a packet transmission queue,
202 * so that the caller does not ordinarily have to do additional queuing of
203 * packets. Thus, this function is unlikely to ever be useful. */
204 void (*send_wait)(struct netdev *netdev);
206 /* Sets 'netdev''s Ethernet address to 'mac' */
207 int (*set_etheraddr)(struct netdev *netdev, const uint8_t mac[6]);
209 /* Retrieves 'netdev''s Ethernet address into 'mac'. */
210 int (*get_etheraddr)(const struct netdev *netdev, uint8_t mac[6]);
212 /* Retrieves 'netdev''s MTU into '*mtup'.
214 * The MTU is the maximum size of transmitted (and received) packets, in
215 * bytes, not including the hardware header; thus, this is typically 1500
216 * bytes for Ethernet devices.*/
217 int (*get_mtu)(const struct netdev *netdev, int *mtup);
219 /* Returns the ifindex of 'netdev', if successful, as a positive number.
220 * On failure, returns a negative errno value.
222 * The desired semantics of the ifindex value are a combination of those
223 * specified by POSIX for if_nametoindex() and by SNMP for ifIndex. An
224 * ifindex value should be unique within a host and remain stable at least
225 * until reboot. SNMP says an ifindex "ranges between 1 and the value of
226 * ifNumber" but many systems do not follow this rule anyhow. */
227 int (*get_ifindex)(const struct netdev *netdev);
229 /* Sets 'carrier' to true if carrier is active (link light is on) on
231 int (*get_carrier)(const struct netdev *netdev, bool *carrier);
233 /* Retrieves current device stats for 'netdev' into 'stats'.
235 * A network device that supports some statistics but not others, it should
236 * set the values of the unsupported statistics to all-1-bits
238 int (*get_stats)(const struct netdev *netdev, struct netdev_stats *);
240 /* Stores the features supported by 'netdev' into each of '*current',
241 * '*advertised', '*supported', and '*peer'. Each value is a bitmap of
242 * "enum ofp_port_features" bits, in host byte order. */
243 int (*get_features)(struct netdev *netdev,
244 uint32_t *current, uint32_t *advertised,
245 uint32_t *supported, uint32_t *peer);
247 /* Set the features advertised by 'netdev' to 'advertise', which is a
248 * bitmap of "enum ofp_port_features" bits, in host byte order.
250 * This function may be set to null for a network device that does not
251 * support configuring advertisements. */
252 int (*set_advertisements)(struct netdev *netdev, uint32_t advertise);
254 /* If 'netdev' is a VLAN network device (e.g. one created with vconfig(8)),
255 * sets '*vlan_vid' to the VLAN VID associated with that device and returns
258 * Returns ENOENT if 'netdev' is a network device that is not a
261 * This function should be set to null if it doesn't make any sense for
262 * your network device (it probably doesn't). */
263 int (*get_vlan_vid)(const struct netdev *netdev, int *vlan_vid);
265 /* Attempts to set input rate limiting (policing) policy, such that up to
266 * 'kbits_rate' kbps of traffic is accepted, with a maximum accumulative
267 * burst size of 'kbits' kb.
269 * This function may be set to null if policing is not supported. */
270 int (*set_policing)(struct netdev *netdev, unsigned int kbits_rate,
271 unsigned int kbits_burst);
273 /* If 'netdev' has an assigned IPv4 address, sets '*address' to that
274 * address and '*netmask' to the associated netmask.
276 * The following error values have well-defined meanings:
278 * - EADDRNOTAVAIL: 'netdev' has no assigned IPv4 address.
280 * - EOPNOTSUPP: No IPv4 network stack attached to 'netdev'.
282 * This function may be set to null if it would always return EOPNOTSUPP
284 int (*get_in4)(const struct netdev *netdev, struct in_addr *address,
285 struct in_addr *netmask);
287 /* Assigns 'addr' as 'netdev''s IPv4 address and 'mask' as its netmask. If
288 * 'addr' is INADDR_ANY, 'netdev''s IPv4 address is cleared.
290 * This function may be set to null if it would always return EOPNOTSUPP
292 int (*set_in4)(struct netdev *netdev, struct in_addr addr,
293 struct in_addr mask);
295 /* If 'netdev' has an assigned IPv6 address, sets '*in6' to that address.
297 * The following error values have well-defined meanings:
299 * - EADDRNOTAVAIL: 'netdev' has no assigned IPv6 address.
301 * - EOPNOTSUPP: No IPv6 network stack attached to 'netdev'.
303 * This function may be set to null if it would always return EOPNOTSUPP
305 int (*get_in6)(const struct netdev *netdev, struct in6_addr *in6);
307 /* Adds 'router' as a default IP gateway for the TCP/IP stack that
308 * corresponds to 'netdev'.
310 * This function may be set to null if it would always return EOPNOTSUPP
312 int (*add_router)(struct netdev *netdev, struct in_addr router);
314 /* Looks up the next hop for 'host'. If succesful, stores the next hop
315 * gateway's address (0 if 'host' is on a directly connected network) in
316 * '*next_hop' and a copy of the name of the device to reach 'host' in
317 * '*netdev_name', and returns 0. The caller is responsible for freeing
318 * '*netdev_name' (by calling free()).
320 * This function may be set to null if it would always return EOPNOTSUPP
322 int (*get_next_hop)(const struct in_addr *host, struct in_addr *next_hop,
325 /* Looks up the ARP table entry for 'ip' on 'netdev' and stores the
326 * corresponding MAC address in 'mac'. A return value of ENXIO, in
327 * particular, indicates that there is no ARP table entry for 'ip' on
330 * This function may be set to null if it would always return EOPNOTSUPP
332 int (*arp_lookup)(const struct netdev *netdev, uint32_t ip, uint8_t mac[6]);
334 /* Retrieves the current set of flags on 'netdev' into '*old_flags'.
335 * Then, turns off the flags that are set to 1 in 'off' and turns on the
336 * flags that are set to 1 in 'on'. (No bit will be set to 1 in both 'off'
337 * and 'on'; that is, off & on == 0.)
339 * This function may be invoked from a signal handler. Therefore, it
340 * should not do anything that is not signal-safe (such as logging). */
341 int (*update_flags)(struct netdev *netdev, enum netdev_flags off,
342 enum netdev_flags on, enum netdev_flags *old_flags);
344 /* Arranges for 'cb' to be called whenever one of the attributes of
345 * 'netdev' changes and sets '*notifierp' to a newly created
346 * netdev_notifier that represents this arrangement. The created notifier
347 * will have its 'netdev', 'cb', and 'aux' members set to the values of the
348 * corresponding parameters. */
349 int (*poll_add)(struct netdev *netdev,
350 void (*cb)(struct netdev_notifier *notifier), void *aux,
351 struct netdev_notifier **notifierp);
353 /* Cancels poll notification for 'notifier'. */
354 void (*poll_remove)(struct netdev_notifier *notifier);
357 extern const struct netdev_class netdev_linux_class;
358 extern const struct netdev_class netdev_tap_class;
359 extern const struct netdev_class netdev_gre_class;
361 #endif /* netdev.h */