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git.proxmox.com Git - ovs.git/blob - lib/netlink-socket.c
719f6589d9eeae8b82b1062620c53b32a52926c5
2 * Copyright (c) 2008, 2009, 2010, 2011 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.
18 #include "netlink-socket.h"
23 #include <sys/types.h>
26 #include "dynamic-string.h"
30 #include "netlink-protocol.h"
32 #include "poll-loop.h"
33 #include "socket-util.h"
37 VLOG_DEFINE_THIS_MODULE(netlink_socket
);
39 COVERAGE_DEFINE(netlink_overflow
);
40 COVERAGE_DEFINE(netlink_received
);
41 COVERAGE_DEFINE(netlink_recv_jumbo
);
42 COVERAGE_DEFINE(netlink_send
);
43 COVERAGE_DEFINE(netlink_sent
);
45 /* Linux header file confusion causes this to be undefined. */
47 #define SOL_NETLINK 270
50 /* A single (bad) Netlink message can in theory dump out many, many log
51 * messages, so the burst size is set quite high here to avoid missing useful
52 * information. Also, at high logging levels we log *all* Netlink messages. */
53 static struct vlog_rate_limit rl
= VLOG_RATE_LIMIT_INIT(60, 600);
55 static void log_nlmsg(const char *function
, int error
,
56 const void *message
, size_t size
, int protocol
);
58 /* Netlink sockets. */
69 static int alloc_pid(uint32_t *);
70 static void free_pid(uint32_t);
71 static int nl_sock_cow__(struct nl_sock
*);
73 /* Creates a new netlink socket for the given netlink 'protocol'
74 * (NETLINK_ROUTE, NETLINK_GENERIC, ...). Returns 0 and sets '*sockp' to the
75 * new socket if successful, otherwise returns a positive errno value. */
77 nl_sock_create(int protocol
, struct nl_sock
**sockp
)
80 struct sockaddr_nl local
, remote
;
84 sock
= malloc(sizeof *sock
);
89 sock
->fd
= socket(AF_NETLINK
, SOCK_RAW
, protocol
);
91 VLOG_ERR("fcntl: %s", strerror(errno
));
94 sock
->protocol
= protocol
;
95 sock
->any_groups
= false;
98 retval
= alloc_pid(&sock
->pid
);
103 /* Bind local address as our selected pid. */
104 memset(&local
, 0, sizeof local
);
105 local
.nl_family
= AF_NETLINK
;
106 local
.nl_pid
= sock
->pid
;
107 if (bind(sock
->fd
, (struct sockaddr
*) &local
, sizeof local
) < 0) {
108 VLOG_ERR("bind(%"PRIu32
"): %s", sock
->pid
, strerror(errno
));
112 /* Bind remote address as the kernel (pid 0). */
113 memset(&remote
, 0, sizeof remote
);
114 remote
.nl_family
= AF_NETLINK
;
116 if (connect(sock
->fd
, (struct sockaddr
*) &remote
, sizeof remote
) < 0) {
117 VLOG_ERR("connect(0): %s", strerror(errno
));
140 /* Creates a new netlink socket for the same protocol as 'src'. Returns 0 and
141 * sets '*sockp' to the new socket if successful, otherwise returns a positive
144 nl_sock_clone(const struct nl_sock
*src
, struct nl_sock
**sockp
)
146 return nl_sock_create(src
->protocol
, sockp
);
149 /* Destroys netlink socket 'sock'. */
151 nl_sock_destroy(struct nl_sock
*sock
)
164 /* Tries to add 'sock' as a listener for 'multicast_group'. Returns 0 if
165 * successful, otherwise a positive errno value.
167 * Multicast group numbers are always positive.
169 * It is not an error to attempt to join a multicast group to which a socket
170 * already belongs. */
172 nl_sock_join_mcgroup(struct nl_sock
*sock
, unsigned int multicast_group
)
174 int error
= nl_sock_cow__(sock
);
178 if (setsockopt(sock
->fd
, SOL_NETLINK
, NETLINK_ADD_MEMBERSHIP
,
179 &multicast_group
, sizeof multicast_group
) < 0) {
180 VLOG_WARN("could not join multicast group %u (%s)",
181 multicast_group
, strerror(errno
));
184 sock
->any_groups
= true;
188 /* Tries to make 'sock' stop listening to 'multicast_group'. Returns 0 if
189 * successful, otherwise a positive errno value.
191 * Multicast group numbers are always positive.
193 * It is not an error to attempt to leave a multicast group to which a socket
196 * On success, reading from 'sock' will still return any messages that were
197 * received on 'multicast_group' before the group was left. */
199 nl_sock_leave_mcgroup(struct nl_sock
*sock
, unsigned int multicast_group
)
202 if (setsockopt(sock
->fd
, SOL_NETLINK
, NETLINK_DROP_MEMBERSHIP
,
203 &multicast_group
, sizeof multicast_group
) < 0) {
204 VLOG_WARN("could not leave multicast group %u (%s)",
205 multicast_group
, strerror(errno
));
212 nl_sock_send__(struct nl_sock
*sock
, const struct ofpbuf
*msg
, bool wait
)
214 struct nlmsghdr
*nlmsg
= nl_msg_nlmsghdr(msg
);
217 nlmsg
->nlmsg_len
= msg
->size
;
218 nlmsg
->nlmsg_pid
= sock
->pid
;
221 retval
= send(sock
->fd
, msg
->data
, msg
->size
, wait
? 0 : MSG_DONTWAIT
);
222 error
= retval
< 0 ? errno
: 0;
223 } while (error
== EINTR
);
224 log_nlmsg(__func__
, error
, msg
->data
, msg
->size
, sock
->protocol
);
226 COVERAGE_INC(netlink_sent
);
231 /* Tries to send 'msg', which must contain a Netlink message, to the kernel on
232 * 'sock'. nlmsg_len in 'msg' will be finalized to match msg->size, and
233 * nlmsg_pid will be set to 'sock''s pid, before the message is sent.
235 * Returns 0 if successful, otherwise a positive errno value. If
236 * 'wait' is true, then the send will wait until buffer space is ready;
237 * otherwise, returns EAGAIN if the 'sock' send buffer is full. */
239 nl_sock_send(struct nl_sock
*sock
, const struct ofpbuf
*msg
, bool wait
)
241 int error
= nl_sock_cow__(sock
);
245 return nl_sock_send__(sock
, msg
, wait
);
248 /* This stress option is useful for testing that OVS properly tolerates
249 * -ENOBUFS on NetLink sockets. Such errors are unavoidable because they can
250 * occur if the kernel cannot temporarily allocate enough GFP_ATOMIC memory to
251 * reply to a request. They can also occur if messages arrive on a multicast
252 * channel faster than OVS can process them. */
254 netlink_overflow
, "simulate netlink socket receive buffer overflow",
258 nl_sock_recv__(struct nl_sock
*sock
, struct ofpbuf
**bufp
, bool wait
)
260 /* We can't accurately predict the size of the data to be received. Most
261 * received data will fit in a 2 kB buffer, so we allocate that much space.
262 * In case the data is actually bigger than that, we make available enough
263 * additional space to allow Netlink messages to be up to 64 kB long (a
264 * reasonable figure since that's the maximum length of a Netlink
266 enum { MAX_SIZE
= 65536 };
267 enum { HEAD_SIZE
= 2048 };
268 enum { TAIL_SIZE
= MAX_SIZE
- HEAD_SIZE
};
270 struct nlmsghdr
*nlmsghdr
;
271 uint8_t tail
[TAIL_SIZE
];
279 buf
= ofpbuf_new(HEAD_SIZE
);
280 iov
[0].iov_base
= buf
->data
;
281 iov
[0].iov_len
= HEAD_SIZE
;
282 iov
[1].iov_base
= tail
;
283 iov
[1].iov_len
= TAIL_SIZE
;
285 memset(&msg
, 0, sizeof msg
);
290 retval
= recvmsg(sock
->fd
, &msg
, wait
? 0 : MSG_DONTWAIT
);
291 } while (retval
< 0 && errno
== EINTR
);
295 if (error
== ENOBUFS
) {
296 /* Socket receive buffer overflow dropped one or more messages that
297 * the kernel tried to send to us. */
298 COVERAGE_INC(netlink_overflow
);
304 if (msg
.msg_flags
& MSG_TRUNC
) {
305 VLOG_ERR_RL(&rl
, "truncated message (longer than %d bytes)", MAX_SIZE
);
310 ofpbuf_put_uninit(buf
, MIN(retval
, HEAD_SIZE
));
311 if (retval
> HEAD_SIZE
) {
312 COVERAGE_INC(netlink_recv_jumbo
);
313 ofpbuf_put(buf
, tail
, retval
- HEAD_SIZE
);
316 nlmsghdr
= buf
->data
;
317 if (retval
< sizeof *nlmsghdr
318 || nlmsghdr
->nlmsg_len
< sizeof *nlmsghdr
319 || nlmsghdr
->nlmsg_len
> retval
) {
320 VLOG_ERR_RL(&rl
, "received invalid nlmsg (%zd bytes < %d)",
321 retval
, NLMSG_HDRLEN
);
326 if (STRESS(netlink_overflow
)) {
332 log_nlmsg(__func__
, 0, buf
->data
, buf
->size
, sock
->protocol
);
333 COVERAGE_INC(netlink_received
);
338 /* Tries to receive a netlink message from the kernel on 'sock'. If
339 * successful, stores the received message into '*bufp' and returns 0. The
340 * caller is responsible for destroying the message with ofpbuf_delete(). On
341 * failure, returns a positive errno value and stores a null pointer into
344 * If 'wait' is true, nl_sock_recv waits for a message to be ready; otherwise,
345 * returns EAGAIN if the 'sock' receive buffer is empty. */
347 nl_sock_recv(struct nl_sock
*sock
, struct ofpbuf
**bufp
, bool wait
)
349 int error
= nl_sock_cow__(sock
);
353 return nl_sock_recv__(sock
, bufp
, wait
);
356 /* Sends 'request' to the kernel via 'sock' and waits for a response. If
357 * successful, returns 0. On failure, returns a positive errno value.
359 * If 'replyp' is nonnull, then on success '*replyp' is set to the kernel's
360 * reply, which the caller is responsible for freeing with ofpbuf_delete(), and
361 * on failure '*replyp' is set to NULL. If 'replyp' is null, then the kernel's
362 * reply, if any, is discarded.
364 * nlmsg_len in 'msg' will be finalized to match msg->size, and nlmsg_pid will
365 * be set to 'sock''s pid, before the message is sent. NLM_F_ACK will be set
368 * The caller is responsible for destroying 'request'.
370 * Bare Netlink is an unreliable transport protocol. This function layers
371 * reliable delivery and reply semantics on top of bare Netlink.
373 * In Netlink, sending a request to the kernel is reliable enough, because the
374 * kernel will tell us if the message cannot be queued (and we will in that
375 * case put it on the transmit queue and wait until it can be delivered).
377 * Receiving the reply is the real problem: if the socket buffer is full when
378 * the kernel tries to send the reply, the reply will be dropped. However, the
379 * kernel sets a flag that a reply has been dropped. The next call to recv
380 * then returns ENOBUFS. We can then re-send the request.
384 * 1. Netlink depends on sequence numbers to match up requests and
385 * replies. The sender of a request supplies a sequence number, and
386 * the reply echos back that sequence number.
388 * This is fine, but (1) some kernel netlink implementations are
389 * broken, in that they fail to echo sequence numbers and (2) this
390 * function will drop packets with non-matching sequence numbers, so
391 * that only a single request can be usefully transacted at a time.
393 * 2. Resending the request causes it to be re-executed, so the request
394 * needs to be idempotent.
397 nl_sock_transact(struct nl_sock
*sock
,
398 const struct ofpbuf
*request
, struct ofpbuf
**replyp
)
400 uint32_t seq
= nl_msg_nlmsghdr(request
)->nlmsg_seq
;
401 struct nlmsghdr
*nlmsghdr
;
402 struct ofpbuf
*reply
;
409 /* Ensure that we get a reply even if this message doesn't ordinarily call
411 nl_msg_nlmsghdr(request
)->nlmsg_flags
|= NLM_F_ACK
;
414 retval
= nl_sock_send(sock
, request
, true);
420 retval
= nl_sock_recv(sock
, &reply
, true);
422 if (retval
== ENOBUFS
) {
423 COVERAGE_INC(netlink_overflow
);
424 VLOG_DBG_RL(&rl
, "receive buffer overflow, resending request");
430 nlmsghdr
= nl_msg_nlmsghdr(reply
);
431 if (seq
!= nlmsghdr
->nlmsg_seq
) {
432 VLOG_DBG_RL(&rl
, "ignoring seq %#"PRIx32
" != expected %#"PRIx32
,
433 nl_msg_nlmsghdr(reply
)->nlmsg_seq
, seq
);
434 ofpbuf_delete(reply
);
438 /* If the reply is an error, discard the reply and return the error code.
440 * Except: if the reply is just an acknowledgement (error code of 0), and
441 * the caller is interested in the reply (replyp != NULL), pass the reply
442 * up to the caller. Otherwise the caller will get a return value of 0
443 * and null '*replyp', which makes unwary callers likely to segfault. */
444 if (nl_msg_nlmsgerr(reply
, &retval
) && (retval
|| !replyp
)) {
445 ofpbuf_delete(reply
);
447 VLOG_DBG_RL(&rl
, "received NAK error=%d (%s)",
448 retval
, strerror(retval
));
450 return retval
!= EAGAIN
? retval
: EPROTO
;
456 ofpbuf_delete(reply
);
461 /* Drain all the messages currently in 'sock''s receive queue. */
463 nl_sock_drain(struct nl_sock
*sock
)
465 int error
= nl_sock_cow__(sock
);
469 return drain_rcvbuf(sock
->fd
);
472 /* The client is attempting some operation on 'sock'. If 'sock' has an ongoing
473 * dump operation, then replace 'sock''s fd with a new socket and hand 'sock''s
474 * old fd over to the dump. */
476 nl_sock_cow__(struct nl_sock
*sock
)
478 struct nl_sock
*copy
;
487 error
= nl_sock_clone(sock
, ©
);
497 sock
->pid
= copy
->pid
;
500 sock
->dump
->sock
= copy
;
506 /* Starts a Netlink "dump" operation, by sending 'request' to the kernel via
507 * 'sock', and initializes 'dump' to reflect the state of the operation.
509 * nlmsg_len in 'msg' will be finalized to match msg->size, and nlmsg_pid will
510 * be set to 'sock''s pid, before the message is sent. NLM_F_DUMP and
511 * NLM_F_ACK will be set in nlmsg_flags.
513 * This Netlink socket library is designed to ensure that the dump is reliable
514 * and that it will not interfere with other operations on 'sock', including
515 * destroying or sending and receiving messages on 'sock'. One corner case is
518 * - If 'sock' has been used to send a request (e.g. with nl_sock_send())
519 * whose response has not yet been received (e.g. with nl_sock_recv()).
520 * This is unusual: usually nl_sock_transact() is used to send a message
521 * and receive its reply all in one go.
523 * This function provides no status indication. An error status for the entire
524 * dump operation is provided when it is completed by calling nl_dump_done().
526 * The caller is responsible for destroying 'request'.
528 * The new 'dump' is independent of 'sock'. 'sock' and 'dump' may be destroyed
532 nl_dump_start(struct nl_dump
*dump
,
533 struct nl_sock
*sock
, const struct ofpbuf
*request
)
535 struct nlmsghdr
*nlmsghdr
= nl_msg_nlmsghdr(request
);
536 nlmsghdr
->nlmsg_flags
|= NLM_F_DUMP
| NLM_F_ACK
;
537 dump
->seq
= nlmsghdr
->nlmsg_seq
;
539 if (sock
->any_groups
|| sock
->dump
) {
540 /* 'sock' might belong to some multicast group, or it already has an
541 * onoging dump. Clone the socket to avoid possibly intermixing
542 * multicast messages or previous dump results with our results. */
543 dump
->status
= nl_sock_clone(sock
, &dump
->sock
);
552 dump
->status
= nl_sock_send__(sock
, request
, true);
555 /* Helper function for nl_dump_next(). */
557 nl_dump_recv(struct nl_dump
*dump
, struct ofpbuf
**bufferp
)
559 struct nlmsghdr
*nlmsghdr
;
560 struct ofpbuf
*buffer
;
563 retval
= nl_sock_recv__(dump
->sock
, bufferp
, true);
565 return retval
== EINTR
? EAGAIN
: retval
;
569 nlmsghdr
= nl_msg_nlmsghdr(buffer
);
570 if (dump
->seq
!= nlmsghdr
->nlmsg_seq
) {
571 VLOG_DBG_RL(&rl
, "ignoring seq %#"PRIx32
" != expected %#"PRIx32
,
572 nlmsghdr
->nlmsg_seq
, dump
->seq
);
576 if (nl_msg_nlmsgerr(buffer
, &retval
)) {
577 VLOG_INFO_RL(&rl
, "netlink dump request error (%s)",
579 return retval
&& retval
!= EAGAIN
? retval
: EPROTO
;
585 /* Attempts to retrieve another reply from 'dump', which must have been
586 * initialized with nl_dump_start().
588 * If successful, returns true and points 'reply->data' and 'reply->size' to
589 * the message that was retrieved. The caller must not modify 'reply' (because
590 * it points into the middle of a larger buffer).
592 * On failure, returns false and sets 'reply->data' to NULL and 'reply->size'
593 * to 0. Failure might indicate an actual error or merely the end of replies.
594 * An error status for the entire dump operation is provided when it is
595 * completed by calling nl_dump_done().
598 nl_dump_next(struct nl_dump
*dump
, struct ofpbuf
*reply
)
600 struct nlmsghdr
*nlmsghdr
;
608 if (dump
->buffer
&& !dump
->buffer
->size
) {
609 ofpbuf_delete(dump
->buffer
);
612 while (!dump
->buffer
) {
613 int retval
= nl_dump_recv(dump
, &dump
->buffer
);
615 ofpbuf_delete(dump
->buffer
);
617 if (retval
!= EAGAIN
) {
618 dump
->status
= retval
;
624 nlmsghdr
= nl_msg_next(dump
->buffer
, reply
);
626 VLOG_WARN_RL(&rl
, "netlink dump reply contains message fragment");
627 dump
->status
= EPROTO
;
629 } else if (nlmsghdr
->nlmsg_type
== NLMSG_DONE
) {
637 /* Completes Netlink dump operation 'dump', which must have been initialized
638 * with nl_dump_start(). Returns 0 if the dump operation was error-free,
639 * otherwise a positive errno value describing the problem. */
641 nl_dump_done(struct nl_dump
*dump
)
643 /* Drain any remaining messages that the client didn't read. Otherwise the
644 * kernel will continue to queue them up and waste buffer space. */
645 while (!dump
->status
) {
647 if (!nl_dump_next(dump
, &reply
)) {
648 assert(dump
->status
);
653 if (dump
->sock
->dump
) {
654 dump
->sock
->dump
= NULL
;
656 nl_sock_destroy(dump
->sock
);
659 ofpbuf_delete(dump
->buffer
);
660 return dump
->status
== EOF
? 0 : dump
->status
;
663 /* Causes poll_block() to wake up when any of the specified 'events' (which is
664 * a OR'd combination of POLLIN, POLLOUT, etc.) occur on 'sock'. */
666 nl_sock_wait(const struct nl_sock
*sock
, short int events
)
668 poll_fd_wait(sock
->fd
, events
);
674 struct hmap_node hmap_node
;
679 static struct hmap genl_families
= HMAP_INITIALIZER(&genl_families
);
681 static const struct nl_policy family_policy
[CTRL_ATTR_MAX
+ 1] = {
682 [CTRL_ATTR_FAMILY_ID
] = {.type
= NL_A_U16
},
685 static struct genl_family
*
686 find_genl_family_by_id(uint16_t id
)
688 struct genl_family
*family
;
690 HMAP_FOR_EACH_IN_BUCKET (family
, hmap_node
, hash_int(id
, 0),
692 if (family
->id
== id
) {
700 define_genl_family(uint16_t id
, const char *name
)
702 struct genl_family
*family
= find_genl_family_by_id(id
);
705 if (!strcmp(family
->name
, name
)) {
710 family
= xmalloc(sizeof *family
);
712 hmap_insert(&genl_families
, &family
->hmap_node
, hash_int(id
, 0));
714 family
->name
= xstrdup(name
);
718 genl_family_to_name(uint16_t id
)
720 if (id
== GENL_ID_CTRL
) {
723 struct genl_family
*family
= find_genl_family_by_id(id
);
724 return family
? family
->name
: "unknown";
728 static int do_lookup_genl_family(const char *name
)
730 struct nl_sock
*sock
;
731 struct ofpbuf request
, *reply
;
732 struct nlattr
*attrs
[ARRAY_SIZE(family_policy
)];
735 retval
= nl_sock_create(NETLINK_GENERIC
, &sock
);
740 ofpbuf_init(&request
, 0);
741 nl_msg_put_genlmsghdr(&request
, 0, GENL_ID_CTRL
, NLM_F_REQUEST
,
742 CTRL_CMD_GETFAMILY
, 1);
743 nl_msg_put_string(&request
, CTRL_ATTR_FAMILY_NAME
, name
);
744 retval
= nl_sock_transact(sock
, &request
, &reply
);
745 ofpbuf_uninit(&request
);
747 nl_sock_destroy(sock
);
751 if (!nl_policy_parse(reply
, NLMSG_HDRLEN
+ GENL_HDRLEN
,
752 family_policy
, attrs
, ARRAY_SIZE(family_policy
))) {
753 nl_sock_destroy(sock
);
754 ofpbuf_delete(reply
);
758 retval
= nl_attr_get_u16(attrs
[CTRL_ATTR_FAMILY_ID
]);
762 define_genl_family(retval
, name
);
764 nl_sock_destroy(sock
);
765 ofpbuf_delete(reply
);
770 /* If '*number' is 0, translates the given Generic Netlink family 'name' to a
771 * number and stores it in '*number'. If successful, returns 0 and the caller
772 * may use '*number' as the family number. On failure, returns a positive
773 * errno value and '*number' caches the errno value. */
775 nl_lookup_genl_family(const char *name
, int *number
)
778 *number
= do_lookup_genl_family(name
);
779 assert(*number
!= 0);
781 return *number
> 0 ? 0 : -*number
;
786 * Every Netlink socket must be bound to a unique 32-bit PID. By convention,
787 * programs that have a single Netlink socket use their Unix process ID as PID,
788 * and programs with multiple Netlink sockets add a unique per-socket
789 * identifier in the bits above the Unix process ID.
791 * The kernel has Netlink PID 0.
794 /* Parameters for how many bits in the PID should come from the Unix process ID
795 * and how many unique per-socket. */
796 #define SOCKET_BITS 10
797 #define MAX_SOCKETS (1u << SOCKET_BITS)
799 #define PROCESS_BITS (32 - SOCKET_BITS)
800 #define MAX_PROCESSES (1u << PROCESS_BITS)
801 #define PROCESS_MASK ((uint32_t) (MAX_PROCESSES - 1))
803 /* Bit vector of unused socket identifiers. */
804 static uint32_t avail_sockets
[ROUND_UP(MAX_SOCKETS
, 32)];
806 /* Allocates and returns a new Netlink PID. */
808 alloc_pid(uint32_t *pid
)
812 for (i
= 0; i
< MAX_SOCKETS
; i
++) {
813 if ((avail_sockets
[i
/ 32] & (1u << (i
% 32))) == 0) {
814 avail_sockets
[i
/ 32] |= 1u << (i
% 32);
815 *pid
= (getpid() & PROCESS_MASK
) | (i
<< PROCESS_BITS
);
819 VLOG_ERR("netlink pid space exhausted");
823 /* Makes the specified 'pid' available for reuse. */
825 free_pid(uint32_t pid
)
827 int sock
= pid
>> PROCESS_BITS
;
828 assert(avail_sockets
[sock
/ 32] & (1u << (sock
% 32)));
829 avail_sockets
[sock
/ 32] &= ~(1u << (sock
% 32));
833 nlmsghdr_to_string(const struct nlmsghdr
*h
, int protocol
, struct ds
*ds
)
839 static const struct nlmsg_flag flags
[] = {
840 { NLM_F_REQUEST
, "REQUEST" },
841 { NLM_F_MULTI
, "MULTI" },
842 { NLM_F_ACK
, "ACK" },
843 { NLM_F_ECHO
, "ECHO" },
844 { NLM_F_DUMP
, "DUMP" },
845 { NLM_F_ROOT
, "ROOT" },
846 { NLM_F_MATCH
, "MATCH" },
847 { NLM_F_ATOMIC
, "ATOMIC" },
849 const struct nlmsg_flag
*flag
;
852 ds_put_format(ds
, "nl(len:%"PRIu32
", type=%"PRIu16
,
853 h
->nlmsg_len
, h
->nlmsg_type
);
854 if (h
->nlmsg_type
== NLMSG_NOOP
) {
855 ds_put_cstr(ds
, "(no-op)");
856 } else if (h
->nlmsg_type
== NLMSG_ERROR
) {
857 ds_put_cstr(ds
, "(error)");
858 } else if (h
->nlmsg_type
== NLMSG_DONE
) {
859 ds_put_cstr(ds
, "(done)");
860 } else if (h
->nlmsg_type
== NLMSG_OVERRUN
) {
861 ds_put_cstr(ds
, "(overrun)");
862 } else if (h
->nlmsg_type
< NLMSG_MIN_TYPE
) {
863 ds_put_cstr(ds
, "(reserved)");
864 } else if (protocol
== NETLINK_GENERIC
) {
865 ds_put_format(ds
, "(%s)", genl_family_to_name(h
->nlmsg_type
));
867 ds_put_cstr(ds
, "(family-defined)");
869 ds_put_format(ds
, ", flags=%"PRIx16
, h
->nlmsg_flags
);
870 flags_left
= h
->nlmsg_flags
;
871 for (flag
= flags
; flag
< &flags
[ARRAY_SIZE(flags
)]; flag
++) {
872 if ((flags_left
& flag
->bits
) == flag
->bits
) {
873 ds_put_format(ds
, "[%s]", flag
->name
);
874 flags_left
&= ~flag
->bits
;
878 ds_put_format(ds
, "[OTHER:%"PRIx16
"]", flags_left
);
880 ds_put_format(ds
, ", seq=%"PRIx32
", pid=%"PRIu32
"(%d:%d))",
881 h
->nlmsg_seq
, h
->nlmsg_pid
,
882 (int) (h
->nlmsg_pid
& PROCESS_MASK
),
883 (int) (h
->nlmsg_pid
>> PROCESS_BITS
));
887 nlmsg_to_string(const struct ofpbuf
*buffer
, int protocol
)
889 struct ds ds
= DS_EMPTY_INITIALIZER
;
890 const struct nlmsghdr
*h
= ofpbuf_at(buffer
, 0, NLMSG_HDRLEN
);
892 nlmsghdr_to_string(h
, protocol
, &ds
);
893 if (h
->nlmsg_type
== NLMSG_ERROR
) {
894 const struct nlmsgerr
*e
;
895 e
= ofpbuf_at(buffer
, NLMSG_HDRLEN
,
896 NLMSG_ALIGN(sizeof(struct nlmsgerr
)));
898 ds_put_format(&ds
, " error(%d", e
->error
);
900 ds_put_format(&ds
, "(%s)", strerror(-e
->error
));
902 ds_put_cstr(&ds
, ", in-reply-to(");
903 nlmsghdr_to_string(&e
->msg
, protocol
, &ds
);
904 ds_put_cstr(&ds
, "))");
906 ds_put_cstr(&ds
, " error(truncated)");
908 } else if (h
->nlmsg_type
== NLMSG_DONE
) {
909 int *error
= ofpbuf_at(buffer
, NLMSG_HDRLEN
, sizeof *error
);
911 ds_put_format(&ds
, " done(%d", *error
);
913 ds_put_format(&ds
, "(%s)", strerror(-*error
));
915 ds_put_cstr(&ds
, ")");
917 ds_put_cstr(&ds
, " done(truncated)");
919 } else if (protocol
== NETLINK_GENERIC
) {
920 struct genlmsghdr
*genl
= nl_msg_genlmsghdr(buffer
);
922 ds_put_format(&ds
, ",genl(cmd=%"PRIu8
",version=%"PRIu8
")",
923 genl
->cmd
, genl
->version
);
927 ds_put_cstr(&ds
, "nl(truncated)");
933 log_nlmsg(const char *function
, int error
,
934 const void *message
, size_t size
, int protocol
)
936 struct ofpbuf buffer
;
939 if (!VLOG_IS_DBG_ENABLED()) {
943 ofpbuf_use_const(&buffer
, message
, size
);
944 nlmsg
= nlmsg_to_string(&buffer
, protocol
);
945 VLOG_DBG_RL(&rl
, "%s (%s): %s", function
, strerror(error
), nlmsg
);