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784e7a2531
Signed-off-by: Laurent Vivier <lvivier@redhat.com> Reviewed-by: Stefano Brivio <sbrivio@redhat.com> Reviewed-by: David Gibson <david@gibson.dropbear.id.au> Acked-by: Michael S. Tsirkin <mst@redhat.com> Acked-by: Markus Armbruster <armbru@redhat.com> (QAPI schema) Signed-off-by: Jason Wang <jasowang@redhat.com>
624 lines
19 KiB
C
624 lines
19 KiB
C
/*
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* QEMU System Emulator
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*
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* Copyright (c) 2003-2008 Fabrice Bellard
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* Copyright (c) 2022 Red Hat, Inc.
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*
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* Permission is hereby granted, free of charge, to any person obtaining a copy
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* of this software and associated documentation files (the "Software"), to deal
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* in the Software without restriction, including without limitation the rights
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* to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
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* copies of the Software, and to permit persons to whom the Software is
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* furnished to do so, subject to the following conditions:
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*
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* The above copyright notice and this permission notice shall be included in
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* all copies or substantial portions of the Software.
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*
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* THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
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* IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
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* FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL
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* THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
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* LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
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* OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
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* THE SOFTWARE.
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*/
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#include "qemu/osdep.h"
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#include "net/net.h"
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#include "clients.h"
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#include "monitor/monitor.h"
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#include "qapi/error.h"
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#include "qemu/error-report.h"
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#include "qemu/option.h"
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#include "qemu/sockets.h"
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#include "qemu/iov.h"
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#include "qemu/main-loop.h"
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#include "qemu/cutils.h"
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typedef struct NetDgramState {
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NetClientState nc;
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int fd;
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SocketReadState rs;
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bool read_poll; /* waiting to receive data? */
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bool write_poll; /* waiting to transmit data? */
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/* contains destination iff connectionless */
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struct sockaddr *dest_addr;
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socklen_t dest_len;
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} NetDgramState;
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static void net_dgram_send(void *opaque);
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static void net_dgram_writable(void *opaque);
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static void net_dgram_update_fd_handler(NetDgramState *s)
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{
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qemu_set_fd_handler(s->fd,
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s->read_poll ? net_dgram_send : NULL,
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s->write_poll ? net_dgram_writable : NULL,
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s);
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}
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static void net_dgram_read_poll(NetDgramState *s, bool enable)
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{
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s->read_poll = enable;
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net_dgram_update_fd_handler(s);
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}
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static void net_dgram_write_poll(NetDgramState *s, bool enable)
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{
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s->write_poll = enable;
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net_dgram_update_fd_handler(s);
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}
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static void net_dgram_writable(void *opaque)
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{
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NetDgramState *s = opaque;
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net_dgram_write_poll(s, false);
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qemu_flush_queued_packets(&s->nc);
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}
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static ssize_t net_dgram_receive(NetClientState *nc,
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const uint8_t *buf, size_t size)
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{
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NetDgramState *s = DO_UPCAST(NetDgramState, nc, nc);
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ssize_t ret;
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do {
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if (s->dest_addr) {
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ret = sendto(s->fd, buf, size, 0, s->dest_addr, s->dest_len);
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} else {
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ret = send(s->fd, buf, size, 0);
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}
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} while (ret == -1 && errno == EINTR);
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if (ret == -1 && errno == EAGAIN) {
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net_dgram_write_poll(s, true);
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return 0;
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}
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return ret;
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}
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static void net_dgram_send_completed(NetClientState *nc, ssize_t len)
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{
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NetDgramState *s = DO_UPCAST(NetDgramState, nc, nc);
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if (!s->read_poll) {
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net_dgram_read_poll(s, true);
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}
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}
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static void net_dgram_rs_finalize(SocketReadState *rs)
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{
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NetDgramState *s = container_of(rs, NetDgramState, rs);
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if (qemu_send_packet_async(&s->nc, rs->buf,
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rs->packet_len,
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net_dgram_send_completed) == 0) {
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net_dgram_read_poll(s, false);
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}
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}
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static void net_dgram_send(void *opaque)
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{
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NetDgramState *s = opaque;
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int size;
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size = recv(s->fd, s->rs.buf, sizeof(s->rs.buf), 0);
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if (size < 0) {
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return;
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}
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if (size == 0) {
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/* end of connection */
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net_dgram_read_poll(s, false);
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net_dgram_write_poll(s, false);
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return;
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}
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if (qemu_send_packet_async(&s->nc, s->rs.buf, size,
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net_dgram_send_completed) == 0) {
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net_dgram_read_poll(s, false);
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}
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}
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static int net_dgram_mcast_create(struct sockaddr_in *mcastaddr,
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struct in_addr *localaddr,
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Error **errp)
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{
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struct ip_mreq imr;
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int fd;
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int val, ret;
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#ifdef __OpenBSD__
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unsigned char loop;
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#else
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int loop;
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#endif
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if (!IN_MULTICAST(ntohl(mcastaddr->sin_addr.s_addr))) {
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error_setg(errp, "specified mcastaddr %s (0x%08x) "
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"does not contain a multicast address",
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inet_ntoa(mcastaddr->sin_addr),
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(int)ntohl(mcastaddr->sin_addr.s_addr));
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return -1;
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}
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fd = qemu_socket(PF_INET, SOCK_DGRAM, 0);
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if (fd < 0) {
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error_setg_errno(errp, errno, "can't create datagram socket");
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return -1;
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}
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/*
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* Allow multiple sockets to bind the same multicast ip and port by setting
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* SO_REUSEADDR. This is the only situation where SO_REUSEADDR should be set
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* on windows. Use socket_set_fast_reuse otherwise as it sets SO_REUSEADDR
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* only on posix systems.
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*/
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val = 1;
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ret = setsockopt(fd, SOL_SOCKET, SO_REUSEADDR, &val, sizeof(val));
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if (ret < 0) {
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error_setg_errno(errp, errno, "can't set socket option SO_REUSEADDR");
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goto fail;
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}
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ret = bind(fd, (struct sockaddr *)mcastaddr, sizeof(*mcastaddr));
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if (ret < 0) {
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error_setg_errno(errp, errno, "can't bind ip=%s to socket",
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inet_ntoa(mcastaddr->sin_addr));
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goto fail;
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}
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/* Add host to multicast group */
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imr.imr_multiaddr = mcastaddr->sin_addr;
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if (localaddr) {
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imr.imr_interface = *localaddr;
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} else {
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imr.imr_interface.s_addr = htonl(INADDR_ANY);
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}
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ret = setsockopt(fd, IPPROTO_IP, IP_ADD_MEMBERSHIP,
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&imr, sizeof(struct ip_mreq));
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if (ret < 0) {
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error_setg_errno(errp, errno,
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"can't add socket to multicast group %s",
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inet_ntoa(imr.imr_multiaddr));
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goto fail;
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}
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/* Force mcast msgs to loopback (eg. several QEMUs in same host */
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loop = 1;
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ret = setsockopt(fd, IPPROTO_IP, IP_MULTICAST_LOOP,
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&loop, sizeof(loop));
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if (ret < 0) {
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error_setg_errno(errp, errno,
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"can't force multicast message to loopback");
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goto fail;
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}
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/* If a bind address is given, only send packets from that address */
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if (localaddr != NULL) {
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ret = setsockopt(fd, IPPROTO_IP, IP_MULTICAST_IF,
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localaddr, sizeof(*localaddr));
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if (ret < 0) {
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error_setg_errno(errp, errno,
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"can't set the default network send interface");
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goto fail;
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}
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}
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qemu_socket_set_nonblock(fd);
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return fd;
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fail:
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if (fd >= 0) {
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closesocket(fd);
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}
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return -1;
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}
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static void net_dgram_cleanup(NetClientState *nc)
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{
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NetDgramState *s = DO_UPCAST(NetDgramState, nc, nc);
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if (s->fd != -1) {
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net_dgram_read_poll(s, false);
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net_dgram_write_poll(s, false);
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close(s->fd);
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s->fd = -1;
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}
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g_free(s->dest_addr);
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s->dest_addr = NULL;
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s->dest_len = 0;
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}
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static NetClientInfo net_dgram_socket_info = {
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.type = NET_CLIENT_DRIVER_DGRAM,
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.size = sizeof(NetDgramState),
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.receive = net_dgram_receive,
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.cleanup = net_dgram_cleanup,
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};
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static NetDgramState *net_dgram_fd_init(NetClientState *peer,
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const char *model,
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const char *name,
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int fd,
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Error **errp)
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{
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NetClientState *nc;
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NetDgramState *s;
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nc = qemu_new_net_client(&net_dgram_socket_info, peer, model, name);
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s = DO_UPCAST(NetDgramState, nc, nc);
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s->fd = fd;
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net_socket_rs_init(&s->rs, net_dgram_rs_finalize, false);
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net_dgram_read_poll(s, true);
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return s;
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}
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static int net_dgram_mcast_init(NetClientState *peer,
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const char *model,
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const char *name,
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SocketAddress *remote,
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SocketAddress *local,
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Error **errp)
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{
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NetDgramState *s;
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int fd, ret;
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struct sockaddr_in *saddr;
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if (remote->type != SOCKET_ADDRESS_TYPE_INET) {
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error_setg(errp, "multicast only support inet type");
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return -1;
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}
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saddr = g_new(struct sockaddr_in, 1);
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if (convert_host_port(saddr, remote->u.inet.host, remote->u.inet.port,
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errp) < 0) {
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g_free(saddr);
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return -1;
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}
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if (!local) {
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fd = net_dgram_mcast_create(saddr, NULL, errp);
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if (fd < 0) {
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g_free(saddr);
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return -1;
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}
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} else {
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switch (local->type) {
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case SOCKET_ADDRESS_TYPE_INET: {
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struct in_addr localaddr;
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if (inet_aton(local->u.inet.host, &localaddr) == 0) {
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g_free(saddr);
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error_setg(errp, "localaddr '%s' is not a valid IPv4 address",
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local->u.inet.host);
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return -1;
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}
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fd = net_dgram_mcast_create(saddr, &localaddr, errp);
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if (fd < 0) {
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g_free(saddr);
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return -1;
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}
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break;
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}
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case SOCKET_ADDRESS_TYPE_FD: {
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int newfd;
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fd = monitor_fd_param(monitor_cur(), local->u.fd.str, errp);
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if (fd == -1) {
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g_free(saddr);
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return -1;
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}
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ret = qemu_socket_try_set_nonblock(fd);
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if (ret < 0) {
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g_free(saddr);
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error_setg_errno(errp, -ret, "%s: Can't use file descriptor %d",
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name, fd);
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return -1;
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}
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/*
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* fd passed: multicast: "learn" dest_addr address from bound
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* address and save it. Because this may be "shared" socket from a
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* "master" process, datagrams would be recv() by ONLY ONE process:
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* we must "clone" this dgram socket --jjo
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*/
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saddr = g_new(struct sockaddr_in, 1);
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if (convert_host_port(saddr, local->u.inet.host, local->u.inet.port,
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errp) < 0) {
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g_free(saddr);
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closesocket(fd);
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return -1;
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}
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/* must be bound */
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if (saddr->sin_addr.s_addr == 0) {
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error_setg(errp, "can't setup multicast destination address");
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g_free(saddr);
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closesocket(fd);
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return -1;
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}
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/* clone dgram socket */
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newfd = net_dgram_mcast_create(saddr, NULL, errp);
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if (newfd < 0) {
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g_free(saddr);
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closesocket(fd);
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return -1;
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}
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/* clone newfd to fd, close newfd */
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dup2(newfd, fd);
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close(newfd);
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break;
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}
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default:
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g_free(saddr);
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error_setg(errp, "only support inet or fd type for local");
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return -1;
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}
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}
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s = net_dgram_fd_init(peer, model, name, fd, errp);
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if (!s) {
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g_free(saddr);
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return -1;
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}
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g_assert(s->dest_addr == NULL);
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s->dest_addr = (struct sockaddr *)saddr;
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s->dest_len = sizeof(*saddr);
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if (!local) {
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qemu_set_info_str(&s->nc, "mcast=%s:%d",
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inet_ntoa(saddr->sin_addr),
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ntohs(saddr->sin_port));
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} else {
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switch (local->type) {
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case SOCKET_ADDRESS_TYPE_INET:
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qemu_set_info_str(&s->nc, "mcast=%s:%d",
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inet_ntoa(saddr->sin_addr),
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ntohs(saddr->sin_port));
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break;
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case SOCKET_ADDRESS_TYPE_FD:
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qemu_set_info_str(&s->nc, "fd=%d (cloned mcast=%s:%d)",
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fd, inet_ntoa(saddr->sin_addr),
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ntohs(saddr->sin_port));
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break;
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default:
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g_assert_not_reached();
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}
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}
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return 0;
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}
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int net_init_dgram(const Netdev *netdev, const char *name,
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NetClientState *peer, Error **errp)
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{
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NetDgramState *s;
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int fd, ret;
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SocketAddress *remote, *local;
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struct sockaddr *dest_addr;
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struct sockaddr_in laddr_in, raddr_in;
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struct sockaddr_un laddr_un, raddr_un;
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socklen_t dest_len;
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assert(netdev->type == NET_CLIENT_DRIVER_DGRAM);
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remote = netdev->u.dgram.remote;
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local = netdev->u.dgram.local;
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/* detect multicast address */
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if (remote && remote->type == SOCKET_ADDRESS_TYPE_INET) {
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struct sockaddr_in mcastaddr;
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if (convert_host_port(&mcastaddr, remote->u.inet.host,
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remote->u.inet.port, errp) < 0) {
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return -1;
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}
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if (IN_MULTICAST(ntohl(mcastaddr.sin_addr.s_addr))) {
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return net_dgram_mcast_init(peer, "dram", name, remote, local,
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errp);
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}
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}
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/* unicast address */
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if (!local) {
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error_setg(errp, "dgram requires local= parameter");
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return -1;
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}
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if (remote) {
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if (local->type == SOCKET_ADDRESS_TYPE_FD) {
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error_setg(errp, "don't set remote with local.fd");
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return -1;
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}
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if (remote->type != local->type) {
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error_setg(errp, "remote and local types must be the same");
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return -1;
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}
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} else {
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if (local->type != SOCKET_ADDRESS_TYPE_FD) {
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error_setg(errp,
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"type=inet or type=unix requires remote parameter");
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return -1;
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}
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}
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switch (local->type) {
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case SOCKET_ADDRESS_TYPE_INET:
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if (convert_host_port(&laddr_in, local->u.inet.host, local->u.inet.port,
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errp) < 0) {
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return -1;
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}
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if (convert_host_port(&raddr_in, remote->u.inet.host,
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remote->u.inet.port, errp) < 0) {
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return -1;
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}
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fd = qemu_socket(PF_INET, SOCK_DGRAM, 0);
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if (fd < 0) {
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error_setg_errno(errp, errno, "can't create datagram socket");
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return -1;
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}
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ret = socket_set_fast_reuse(fd);
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if (ret < 0) {
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error_setg_errno(errp, errno,
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"can't set socket option SO_REUSEADDR");
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closesocket(fd);
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return -1;
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}
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ret = bind(fd, (struct sockaddr *)&laddr_in, sizeof(laddr_in));
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if (ret < 0) {
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error_setg_errno(errp, errno, "can't bind ip=%s to socket",
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inet_ntoa(laddr_in.sin_addr));
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closesocket(fd);
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return -1;
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}
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qemu_socket_set_nonblock(fd);
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dest_len = sizeof(raddr_in);
|
|
dest_addr = g_malloc(dest_len);
|
|
memcpy(dest_addr, &raddr_in, dest_len);
|
|
break;
|
|
case SOCKET_ADDRESS_TYPE_UNIX:
|
|
ret = unlink(local->u.q_unix.path);
|
|
if (ret < 0 && errno != ENOENT) {
|
|
error_setg_errno(errp, errno, "failed to unlink socket %s",
|
|
local->u.q_unix.path);
|
|
return -1;
|
|
}
|
|
|
|
laddr_un.sun_family = PF_UNIX;
|
|
ret = snprintf(laddr_un.sun_path, sizeof(laddr_un.sun_path), "%s",
|
|
local->u.q_unix.path);
|
|
if (ret < 0 || ret >= sizeof(laddr_un.sun_path)) {
|
|
error_setg(errp, "UNIX socket path '%s' is too long",
|
|
local->u.q_unix.path);
|
|
error_append_hint(errp, "Path must be less than %zu bytes\n",
|
|
sizeof(laddr_un.sun_path));
|
|
}
|
|
|
|
raddr_un.sun_family = PF_UNIX;
|
|
ret = snprintf(raddr_un.sun_path, sizeof(raddr_un.sun_path), "%s",
|
|
remote->u.q_unix.path);
|
|
if (ret < 0 || ret >= sizeof(raddr_un.sun_path)) {
|
|
error_setg(errp, "UNIX socket path '%s' is too long",
|
|
remote->u.q_unix.path);
|
|
error_append_hint(errp, "Path must be less than %zu bytes\n",
|
|
sizeof(raddr_un.sun_path));
|
|
}
|
|
|
|
fd = qemu_socket(PF_UNIX, SOCK_DGRAM, 0);
|
|
if (fd < 0) {
|
|
error_setg_errno(errp, errno, "can't create datagram socket");
|
|
return -1;
|
|
}
|
|
|
|
ret = bind(fd, (struct sockaddr *)&laddr_un, sizeof(laddr_un));
|
|
if (ret < 0) {
|
|
error_setg_errno(errp, errno, "can't bind unix=%s to socket",
|
|
laddr_un.sun_path);
|
|
closesocket(fd);
|
|
return -1;
|
|
}
|
|
qemu_socket_set_nonblock(fd);
|
|
|
|
dest_len = sizeof(raddr_un);
|
|
dest_addr = g_malloc(dest_len);
|
|
memcpy(dest_addr, &raddr_un, dest_len);
|
|
break;
|
|
case SOCKET_ADDRESS_TYPE_FD:
|
|
fd = monitor_fd_param(monitor_cur(), local->u.fd.str, errp);
|
|
if (fd == -1) {
|
|
return -1;
|
|
}
|
|
ret = qemu_socket_try_set_nonblock(fd);
|
|
if (ret < 0) {
|
|
error_setg_errno(errp, -ret, "%s: Can't use file descriptor %d",
|
|
name, fd);
|
|
return -1;
|
|
}
|
|
dest_addr = NULL;
|
|
dest_len = 0;
|
|
break;
|
|
default:
|
|
error_setg(errp, "only support inet or fd type for local");
|
|
return -1;
|
|
}
|
|
|
|
s = net_dgram_fd_init(peer, "dgram", name, fd, errp);
|
|
if (!s) {
|
|
return -1;
|
|
}
|
|
|
|
if (remote) {
|
|
g_assert(s->dest_addr == NULL);
|
|
s->dest_addr = dest_addr;
|
|
s->dest_len = dest_len;
|
|
}
|
|
|
|
switch (local->type) {
|
|
case SOCKET_ADDRESS_TYPE_INET:
|
|
qemu_set_info_str(&s->nc, "udp=%s:%d/%s:%d",
|
|
inet_ntoa(laddr_in.sin_addr),
|
|
ntohs(laddr_in.sin_port),
|
|
inet_ntoa(raddr_in.sin_addr),
|
|
ntohs(raddr_in.sin_port));
|
|
break;
|
|
case SOCKET_ADDRESS_TYPE_UNIX:
|
|
qemu_set_info_str(&s->nc, "udp=%s:%s",
|
|
laddr_un.sun_path, raddr_un.sun_path);
|
|
break;
|
|
case SOCKET_ADDRESS_TYPE_FD: {
|
|
SocketAddress *sa;
|
|
SocketAddressType sa_type;
|
|
|
|
sa = socket_local_address(fd, errp);
|
|
if (sa) {
|
|
sa_type = sa->type;
|
|
qapi_free_SocketAddress(sa);
|
|
|
|
qemu_set_info_str(&s->nc, "fd=%d %s", fd,
|
|
SocketAddressType_str(sa_type));
|
|
} else {
|
|
qemu_set_info_str(&s->nc, "fd=%d", fd);
|
|
}
|
|
break;
|
|
}
|
|
default:
|
|
g_assert_not_reached();
|
|
}
|
|
|
|
return 0;
|
|
}
|