qemu/net/socket.c
Daniel P. Berrange e79cd40680 net: fix sending of data with -net socket, listen backend
The use of -net socket,listen was broken in the following
commit

  commit 16a3df403b
  Author: Zhang Chen <zhangchen.fnst@cn.fujitsu.com>
  Date:   Fri May 13 15:35:19 2016 +0800

    net/net: Add SocketReadState for reuse codes

    This function is from net/socket.c, move it to net.c and net.h.
    Add SocketReadState to make others reuse net_fill_rstate().
    suggestion from jason.

This refactored the state out of NetSocketState into a
separate SocketReadState. This refactoring requires
that a callback is provided to be triggered upon
completion of a packet receive from the guest.

The patch only registered this callback in the codepaths
hit by -net socket,connect, not -net socket,listen. So
as a result packets sent by the guest in the latter case
get dropped on the floor.

This bug is hidden because net_fill_rstate() silently
does nothing if the callback is not set.

This patch adds in the middle callback registration
and also adds an assert so that QEMU aborts if there
are any other codepaths hit which are missing the
callback.

Signed-off-by: Daniel P. Berrange <berrange@redhat.com>
Reviewed-by: Zhang Chen <zhangchen.fnst@cn.fujitsu.com>
Signed-off-by: Jason Wang <jasowang@redhat.com>
2016-11-15 15:36:21 +08:00

756 lines
21 KiB
C

/*
* QEMU System Emulator
*
* Copyright (c) 2003-2008 Fabrice Bellard
*
* Permission is hereby granted, free of charge, to any person obtaining a copy
* of this software and associated documentation files (the "Software"), to deal
* in the Software without restriction, including without limitation the rights
* to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
* copies of the Software, and to permit persons to whom the Software is
* furnished to do so, subject to the following conditions:
*
* The above copyright notice and this permission notice shall be included in
* all copies or substantial portions of the Software.
*
* THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
* IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
* FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL
* THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
* LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
* OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
* THE SOFTWARE.
*/
#include "qemu/osdep.h"
#include "net/net.h"
#include "clients.h"
#include "monitor/monitor.h"
#include "qapi/error.h"
#include "qemu-common.h"
#include "qemu/error-report.h"
#include "qemu/option.h"
#include "qemu/sockets.h"
#include "qemu/iov.h"
#include "qemu/main-loop.h"
typedef struct NetSocketState {
NetClientState nc;
int listen_fd;
int fd;
SocketReadState rs;
unsigned int send_index; /* number of bytes sent (only SOCK_STREAM) */
struct sockaddr_in dgram_dst; /* contains inet host and port destination iff connectionless (SOCK_DGRAM) */
IOHandler *send_fn; /* differs between SOCK_STREAM/SOCK_DGRAM */
bool read_poll; /* waiting to receive data? */
bool write_poll; /* waiting to transmit data? */
} NetSocketState;
static void net_socket_accept(void *opaque);
static void net_socket_writable(void *opaque);
static void net_socket_update_fd_handler(NetSocketState *s)
{
qemu_set_fd_handler(s->fd,
s->read_poll ? s->send_fn : NULL,
s->write_poll ? net_socket_writable : NULL,
s);
}
static void net_socket_read_poll(NetSocketState *s, bool enable)
{
s->read_poll = enable;
net_socket_update_fd_handler(s);
}
static void net_socket_write_poll(NetSocketState *s, bool enable)
{
s->write_poll = enable;
net_socket_update_fd_handler(s);
}
static void net_socket_writable(void *opaque)
{
NetSocketState *s = opaque;
net_socket_write_poll(s, false);
qemu_flush_queued_packets(&s->nc);
}
static ssize_t net_socket_receive(NetClientState *nc, const uint8_t *buf, size_t size)
{
NetSocketState *s = DO_UPCAST(NetSocketState, nc, nc);
uint32_t len = htonl(size);
struct iovec iov[] = {
{
.iov_base = &len,
.iov_len = sizeof(len),
}, {
.iov_base = (void *)buf,
.iov_len = size,
},
};
size_t remaining;
ssize_t ret;
remaining = iov_size(iov, 2) - s->send_index;
ret = iov_send(s->fd, iov, 2, s->send_index, remaining);
if (ret == -1 && errno == EAGAIN) {
ret = 0; /* handled further down */
}
if (ret == -1) {
s->send_index = 0;
return -errno;
}
if (ret < (ssize_t)remaining) {
s->send_index += ret;
net_socket_write_poll(s, true);
return 0;
}
s->send_index = 0;
return size;
}
static ssize_t net_socket_receive_dgram(NetClientState *nc, const uint8_t *buf, size_t size)
{
NetSocketState *s = DO_UPCAST(NetSocketState, nc, nc);
ssize_t ret;
do {
ret = qemu_sendto(s->fd, buf, size, 0,
(struct sockaddr *)&s->dgram_dst,
sizeof(s->dgram_dst));
} while (ret == -1 && errno == EINTR);
if (ret == -1 && errno == EAGAIN) {
net_socket_write_poll(s, true);
return 0;
}
return ret;
}
static void net_socket_send_completed(NetClientState *nc, ssize_t len)
{
NetSocketState *s = DO_UPCAST(NetSocketState, nc, nc);
if (!s->read_poll) {
net_socket_read_poll(s, true);
}
}
static void net_socket_rs_finalize(SocketReadState *rs)
{
NetSocketState *s = container_of(rs, NetSocketState, rs);
if (qemu_send_packet_async(&s->nc, rs->buf,
rs->packet_len,
net_socket_send_completed) == 0) {
net_socket_read_poll(s, false);
}
}
static void net_socket_send(void *opaque)
{
NetSocketState *s = opaque;
int size;
int ret;
uint8_t buf1[NET_BUFSIZE];
const uint8_t *buf;
size = qemu_recv(s->fd, buf1, sizeof(buf1), 0);
if (size < 0) {
if (errno != EWOULDBLOCK)
goto eoc;
} else if (size == 0) {
/* end of connection */
eoc:
net_socket_read_poll(s, false);
net_socket_write_poll(s, false);
if (s->listen_fd != -1) {
qemu_set_fd_handler(s->listen_fd, net_socket_accept, NULL, s);
}
closesocket(s->fd);
s->fd = -1;
net_socket_rs_init(&s->rs, net_socket_rs_finalize);
s->nc.link_down = true;
memset(s->nc.info_str, 0, sizeof(s->nc.info_str));
return;
}
buf = buf1;
ret = net_fill_rstate(&s->rs, buf, size);
if (ret == -1) {
goto eoc;
}
}
static void net_socket_send_dgram(void *opaque)
{
NetSocketState *s = opaque;
int size;
size = qemu_recv(s->fd, s->rs.buf, sizeof(s->rs.buf), 0);
if (size < 0)
return;
if (size == 0) {
/* end of connection */
net_socket_read_poll(s, false);
net_socket_write_poll(s, false);
return;
}
if (qemu_send_packet_async(&s->nc, s->rs.buf, size,
net_socket_send_completed) == 0) {
net_socket_read_poll(s, false);
}
}
static int net_socket_mcast_create(struct sockaddr_in *mcastaddr, struct in_addr *localaddr)
{
struct ip_mreq imr;
int fd;
int val, ret;
#ifdef __OpenBSD__
unsigned char loop;
#else
int loop;
#endif
if (!IN_MULTICAST(ntohl(mcastaddr->sin_addr.s_addr))) {
fprintf(stderr, "qemu: error: specified mcastaddr \"%s\" (0x%08x) "
"does not contain a multicast address\n",
inet_ntoa(mcastaddr->sin_addr),
(int)ntohl(mcastaddr->sin_addr.s_addr));
return -1;
}
fd = qemu_socket(PF_INET, SOCK_DGRAM, 0);
if (fd < 0) {
perror("socket(PF_INET, SOCK_DGRAM)");
return -1;
}
/* Allow multiple sockets to bind the same multicast ip and port by setting
* SO_REUSEADDR. This is the only situation where SO_REUSEADDR should be set
* on windows. Use socket_set_fast_reuse otherwise as it sets SO_REUSEADDR
* only on posix systems.
*/
val = 1;
ret = qemu_setsockopt(fd, SOL_SOCKET, SO_REUSEADDR, &val, sizeof(val));
if (ret < 0) {
perror("setsockopt(SOL_SOCKET, SO_REUSEADDR)");
goto fail;
}
ret = bind(fd, (struct sockaddr *)mcastaddr, sizeof(*mcastaddr));
if (ret < 0) {
perror("bind");
goto fail;
}
/* Add host to multicast group */
imr.imr_multiaddr = mcastaddr->sin_addr;
if (localaddr) {
imr.imr_interface = *localaddr;
} else {
imr.imr_interface.s_addr = htonl(INADDR_ANY);
}
ret = qemu_setsockopt(fd, IPPROTO_IP, IP_ADD_MEMBERSHIP,
&imr, sizeof(struct ip_mreq));
if (ret < 0) {
perror("setsockopt(IP_ADD_MEMBERSHIP)");
goto fail;
}
/* Force mcast msgs to loopback (eg. several QEMUs in same host */
loop = 1;
ret = qemu_setsockopt(fd, IPPROTO_IP, IP_MULTICAST_LOOP,
&loop, sizeof(loop));
if (ret < 0) {
perror("setsockopt(SOL_IP, IP_MULTICAST_LOOP)");
goto fail;
}
/* If a bind address is given, only send packets from that address */
if (localaddr != NULL) {
ret = qemu_setsockopt(fd, IPPROTO_IP, IP_MULTICAST_IF,
localaddr, sizeof(*localaddr));
if (ret < 0) {
perror("setsockopt(IP_MULTICAST_IF)");
goto fail;
}
}
qemu_set_nonblock(fd);
return fd;
fail:
if (fd >= 0)
closesocket(fd);
return -1;
}
static void net_socket_cleanup(NetClientState *nc)
{
NetSocketState *s = DO_UPCAST(NetSocketState, nc, nc);
if (s->fd != -1) {
net_socket_read_poll(s, false);
net_socket_write_poll(s, false);
close(s->fd);
s->fd = -1;
}
if (s->listen_fd != -1) {
qemu_set_fd_handler(s->listen_fd, NULL, NULL, NULL);
closesocket(s->listen_fd);
s->listen_fd = -1;
}
}
static NetClientInfo net_dgram_socket_info = {
.type = NET_CLIENT_DRIVER_SOCKET,
.size = sizeof(NetSocketState),
.receive = net_socket_receive_dgram,
.cleanup = net_socket_cleanup,
};
static NetSocketState *net_socket_fd_init_dgram(NetClientState *peer,
const char *model,
const char *name,
int fd, int is_connected)
{
struct sockaddr_in saddr;
int newfd;
socklen_t saddr_len = sizeof(saddr);
NetClientState *nc;
NetSocketState *s;
/* fd passed: multicast: "learn" dgram_dst address from bound address and save it
* Because this may be "shared" socket from a "master" process, datagrams would be recv()
* by ONLY ONE process: we must "clone" this dgram socket --jjo
*/
if (is_connected) {
if (getsockname(fd, (struct sockaddr *) &saddr, &saddr_len) == 0) {
/* must be bound */
if (saddr.sin_addr.s_addr == 0) {
fprintf(stderr, "qemu: error: init_dgram: fd=%d unbound, "
"cannot setup multicast dst addr\n", fd);
goto err;
}
/* clone dgram socket */
newfd = net_socket_mcast_create(&saddr, NULL);
if (newfd < 0) {
/* error already reported by net_socket_mcast_create() */
goto err;
}
/* clone newfd to fd, close newfd */
dup2(newfd, fd);
close(newfd);
} else {
fprintf(stderr,
"qemu: error: init_dgram: fd=%d failed getsockname(): %s\n",
fd, strerror(errno));
goto err;
}
}
nc = qemu_new_net_client(&net_dgram_socket_info, peer, model, name);
s = DO_UPCAST(NetSocketState, nc, nc);
s->fd = fd;
s->listen_fd = -1;
s->send_fn = net_socket_send_dgram;
net_socket_rs_init(&s->rs, net_socket_rs_finalize);
net_socket_read_poll(s, true);
/* mcast: save bound address as dst */
if (is_connected) {
s->dgram_dst = saddr;
snprintf(nc->info_str, sizeof(nc->info_str),
"socket: fd=%d (cloned mcast=%s:%d)",
fd, inet_ntoa(saddr.sin_addr), ntohs(saddr.sin_port));
} else {
snprintf(nc->info_str, sizeof(nc->info_str),
"socket: fd=%d", fd);
}
return s;
err:
closesocket(fd);
return NULL;
}
static void net_socket_connect(void *opaque)
{
NetSocketState *s = opaque;
s->send_fn = net_socket_send;
net_socket_read_poll(s, true);
}
static NetClientInfo net_socket_info = {
.type = NET_CLIENT_DRIVER_SOCKET,
.size = sizeof(NetSocketState),
.receive = net_socket_receive,
.cleanup = net_socket_cleanup,
};
static NetSocketState *net_socket_fd_init_stream(NetClientState *peer,
const char *model,
const char *name,
int fd, int is_connected)
{
NetClientState *nc;
NetSocketState *s;
nc = qemu_new_net_client(&net_socket_info, peer, model, name);
snprintf(nc->info_str, sizeof(nc->info_str), "socket: fd=%d", fd);
s = DO_UPCAST(NetSocketState, nc, nc);
s->fd = fd;
s->listen_fd = -1;
net_socket_rs_init(&s->rs, net_socket_rs_finalize);
/* Disable Nagle algorithm on TCP sockets to reduce latency */
socket_set_nodelay(fd);
if (is_connected) {
net_socket_connect(s);
} else {
qemu_set_fd_handler(s->fd, NULL, net_socket_connect, s);
}
return s;
}
static NetSocketState *net_socket_fd_init(NetClientState *peer,
const char *model, const char *name,
int fd, int is_connected)
{
int so_type = -1, optlen=sizeof(so_type);
if(getsockopt(fd, SOL_SOCKET, SO_TYPE, (char *)&so_type,
(socklen_t *)&optlen)< 0) {
fprintf(stderr, "qemu: error: getsockopt(SO_TYPE) for fd=%d failed\n",
fd);
closesocket(fd);
return NULL;
}
switch(so_type) {
case SOCK_DGRAM:
return net_socket_fd_init_dgram(peer, model, name, fd, is_connected);
case SOCK_STREAM:
return net_socket_fd_init_stream(peer, model, name, fd, is_connected);
default:
/* who knows ... this could be a eg. a pty, do warn and continue as stream */
fprintf(stderr, "qemu: warning: socket type=%d for fd=%d is not SOCK_DGRAM or SOCK_STREAM\n", so_type, fd);
return net_socket_fd_init_stream(peer, model, name, fd, is_connected);
}
return NULL;
}
static void net_socket_accept(void *opaque)
{
NetSocketState *s = opaque;
struct sockaddr_in saddr;
socklen_t len;
int fd;
for(;;) {
len = sizeof(saddr);
fd = qemu_accept(s->listen_fd, (struct sockaddr *)&saddr, &len);
if (fd < 0 && errno != EINTR) {
return;
} else if (fd >= 0) {
qemu_set_fd_handler(s->listen_fd, NULL, NULL, NULL);
break;
}
}
s->fd = fd;
s->nc.link_down = false;
net_socket_connect(s);
snprintf(s->nc.info_str, sizeof(s->nc.info_str),
"socket: connection from %s:%d",
inet_ntoa(saddr.sin_addr), ntohs(saddr.sin_port));
}
static int net_socket_listen_init(NetClientState *peer,
const char *model,
const char *name,
const char *host_str)
{
NetClientState *nc;
NetSocketState *s;
SocketAddress *saddr;
int ret;
Error *local_error = NULL;
saddr = socket_parse(host_str, &local_error);
if (saddr == NULL) {
error_report_err(local_error);
return -1;
}
ret = socket_listen(saddr, &local_error);
if (ret < 0) {
qapi_free_SocketAddress(saddr);
error_report_err(local_error);
return -1;
}
nc = qemu_new_net_client(&net_socket_info, peer, model, name);
s = DO_UPCAST(NetSocketState, nc, nc);
s->fd = -1;
s->listen_fd = ret;
s->nc.link_down = true;
net_socket_rs_init(&s->rs, net_socket_rs_finalize);
qemu_set_fd_handler(s->listen_fd, net_socket_accept, NULL, s);
qapi_free_SocketAddress(saddr);
return 0;
}
typedef struct {
NetClientState *peer;
SocketAddress *saddr;
char *model;
char *name;
} socket_connect_data;
static void socket_connect_data_free(socket_connect_data *c)
{
qapi_free_SocketAddress(c->saddr);
g_free(c->model);
g_free(c->name);
g_free(c);
}
static void net_socket_connected(int fd, Error *err, void *opaque)
{
socket_connect_data *c = opaque;
NetSocketState *s;
char *addr_str = NULL;
Error *local_error = NULL;
addr_str = socket_address_to_string(c->saddr, &local_error);
if (addr_str == NULL) {
error_report_err(local_error);
closesocket(fd);
goto end;
}
s = net_socket_fd_init(c->peer, c->model, c->name, fd, true);
if (!s) {
closesocket(fd);
goto end;
}
snprintf(s->nc.info_str, sizeof(s->nc.info_str),
"socket: connect to %s", addr_str);
end:
g_free(addr_str);
socket_connect_data_free(c);
}
static int net_socket_connect_init(NetClientState *peer,
const char *model,
const char *name,
const char *host_str)
{
socket_connect_data *c = g_new0(socket_connect_data, 1);
int fd = -1;
Error *local_error = NULL;
c->peer = peer;
c->model = g_strdup(model);
c->name = g_strdup(name);
c->saddr = socket_parse(host_str, &local_error);
if (c->saddr == NULL) {
goto err;
}
fd = socket_connect(c->saddr, &local_error, net_socket_connected, c);
if (fd < 0) {
goto err;
}
return 0;
err:
error_report_err(local_error);
socket_connect_data_free(c);
return -1;
}
static int net_socket_mcast_init(NetClientState *peer,
const char *model,
const char *name,
const char *host_str,
const char *localaddr_str)
{
NetSocketState *s;
int fd;
struct sockaddr_in saddr;
struct in_addr localaddr, *param_localaddr;
if (parse_host_port(&saddr, host_str) < 0)
return -1;
if (localaddr_str != NULL) {
if (inet_aton(localaddr_str, &localaddr) == 0)
return -1;
param_localaddr = &localaddr;
} else {
param_localaddr = NULL;
}
fd = net_socket_mcast_create(&saddr, param_localaddr);
if (fd < 0)
return -1;
s = net_socket_fd_init(peer, model, name, fd, 0);
if (!s)
return -1;
s->dgram_dst = saddr;
snprintf(s->nc.info_str, sizeof(s->nc.info_str),
"socket: mcast=%s:%d",
inet_ntoa(saddr.sin_addr), ntohs(saddr.sin_port));
return 0;
}
static int net_socket_udp_init(NetClientState *peer,
const char *model,
const char *name,
const char *rhost,
const char *lhost)
{
NetSocketState *s;
int fd, ret;
struct sockaddr_in laddr, raddr;
if (parse_host_port(&laddr, lhost) < 0) {
return -1;
}
if (parse_host_port(&raddr, rhost) < 0) {
return -1;
}
fd = qemu_socket(PF_INET, SOCK_DGRAM, 0);
if (fd < 0) {
perror("socket(PF_INET, SOCK_DGRAM)");
return -1;
}
ret = socket_set_fast_reuse(fd);
if (ret < 0) {
closesocket(fd);
return -1;
}
ret = bind(fd, (struct sockaddr *)&laddr, sizeof(laddr));
if (ret < 0) {
perror("bind");
closesocket(fd);
return -1;
}
qemu_set_nonblock(fd);
s = net_socket_fd_init(peer, model, name, fd, 0);
if (!s) {
return -1;
}
s->dgram_dst = raddr;
snprintf(s->nc.info_str, sizeof(s->nc.info_str),
"socket: udp=%s:%d",
inet_ntoa(raddr.sin_addr), ntohs(raddr.sin_port));
return 0;
}
int net_init_socket(const Netdev *netdev, const char *name,
NetClientState *peer, Error **errp)
{
/* FIXME error_setg(errp, ...) on failure */
Error *err = NULL;
const NetdevSocketOptions *sock;
assert(netdev->type == NET_CLIENT_DRIVER_SOCKET);
sock = &netdev->u.socket;
if (sock->has_fd + sock->has_listen + sock->has_connect + sock->has_mcast +
sock->has_udp != 1) {
error_report("exactly one of fd=, listen=, connect=, mcast= or udp="
" is required");
return -1;
}
if (sock->has_localaddr && !sock->has_mcast && !sock->has_udp) {
error_report("localaddr= is only valid with mcast= or udp=");
return -1;
}
if (sock->has_fd) {
int fd;
fd = monitor_fd_param(cur_mon, sock->fd, &err);
if (fd == -1) {
error_report_err(err);
return -1;
}
qemu_set_nonblock(fd);
if (!net_socket_fd_init(peer, "socket", name, fd, 1)) {
return -1;
}
return 0;
}
if (sock->has_listen) {
if (net_socket_listen_init(peer, "socket", name, sock->listen) == -1) {
return -1;
}
return 0;
}
if (sock->has_connect) {
if (net_socket_connect_init(peer, "socket", name, sock->connect) ==
-1) {
return -1;
}
return 0;
}
if (sock->has_mcast) {
/* if sock->localaddr is missing, it has been initialized to "all bits
* zero" */
if (net_socket_mcast_init(peer, "socket", name, sock->mcast,
sock->localaddr) == -1) {
return -1;
}
return 0;
}
assert(sock->has_udp);
if (!sock->has_localaddr) {
error_report("localaddr= is mandatory with udp=");
return -1;
}
if (net_socket_udp_init(peer, "socket", name, sock->udp, sock->localaddr) ==
-1) {
return -1;
}
return 0;
}