qemu-e2k/chardev/char-socket.c

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/*
* 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 "chardev/char.h"
#include "io/channel-socket.h"
#include "io/channel-tls.h"
#include "io/channel-websock.h"
#include "io/net-listener.h"
#include "qemu/error-report.h"
#include "qemu/option.h"
#include "qapi/error.h"
#include "qapi/clone-visitor.h"
#include "qapi/qapi-visit-sockets.h"
#include "chardev/char-io.h"
/***********************************************************/
/* TCP Net console */
#define TCP_MAX_FDS 16
typedef struct {
char buf[21];
size_t buflen;
} TCPChardevTelnetInit;
typedef enum {
TCP_CHARDEV_STATE_DISCONNECTED,
TCP_CHARDEV_STATE_CONNECTING,
TCP_CHARDEV_STATE_CONNECTED,
} TCPChardevState;
typedef struct {
Chardev parent;
QIOChannel *ioc; /* Client I/O channel */
QIOChannelSocket *sioc; /* Client master channel */
QIONetListener *listener;
chardev/char-socket: add POLLHUP handler The following behavior was observed for QEMU configured by libvirt to use guest agent as usual for the guests without virtio-serial driver (Windows or the guest remaining in BIOS stage). In QEMU on first connect to listen character device socket the listen socket is removed from poll just after the accept(). virtio_serial_guest_ready() returns 0 and the descriptor of the connected Unix socket is removed from poll and it will not be present in poll() until the guest will initialize the driver and change the state of the serial to "guest connected". In libvirt connect() to guest agent is performed on restart and is run under VM state lock. Connect() is blocking and can wait forever. In this case libvirt can not perform ANY operation on that VM. The bug can be easily reproduced this way: Terminal 1: qemu-system-x86_64 -m 512 -device pci-serial,chardev=serial1 -chardev socket,id=serial1,path=/tmp/console.sock,server,nowait (virtio-serial and isa-serial also fit) Terminal 2: minicom -D unix\#/tmp/console.sock (type something and press enter) C-a x (to exit) Do 3 times: minicom -D unix\#/tmp/console.sock C-a x It needs 4 connections, because the first one is accepted by QEMU, then two are queued by the kernel, and the 4th blocks. The problem is that QEMU doesn't add a read watcher after succesful read until the guest device wants to acquire recieved data, so I propose to install a separate pullhup watcher regardless of whether the device waits for data or not. Signed-off-by: Klim Kireev <klim.kireev@virtuozzo.com> Message-Id: <20180125135129.9305-1-klim.kireev@virtuozzo.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2018-01-25 14:51:29 +01:00
GSource *hup_source;
QCryptoTLSCreds *tls_creds;
char *tls_authz;
TCPChardevState state;
int max_size;
int do_telnetopt;
int do_nodelay;
int *read_msgfds;
size_t read_msgfds_num;
int *write_msgfds;
size_t write_msgfds_num;
SocketAddress *addr;
bool is_listen;
bool is_telnet;
bool is_tn3270;
GSource *telnet_source;
TCPChardevTelnetInit *telnet_init;
bool is_websock;
GSource *reconnect_timer;
int64_t reconnect_time;
bool connect_err_reported;
chardev: fix race with client connections in tcp_chr_wait_connected When the 'reconnect' option is given for a client connection, the qmp_chardev_open_socket_client method will run an asynchronous connection attempt. The QIOChannel socket executes this is a single use background thread, so the connection will succeed immediately (assuming the server is listening). The chardev, however, won't get the result from this background thread until the main loop starts running and processes idle callbacks. Thus when tcp_chr_wait_connected is run s->ioc will be NULL, but the state will be TCP_CHARDEV_STATE_CONNECTING, and there may already be an established connection that will be associated with the chardev by the pending idle callback. tcp_chr_wait_connected doesn't check the state, only s->ioc, so attempts to establish another connection synchronously. If the server allows multiple connections this is unhelpful but not a fatal problem as the duplicate connection will get ignored by the tcp_chr_new_client method when it sees the state is already connected. If the server only supports a single connection, however, the tcp_chr_wait_connected method will hang forever because the server will not accept its synchronous connection attempt until the first connection is closed. To deal with this tcp_chr_wait_connected needs to synchronize with the completion of the background connection task. To do this it needs to create the QIOTask directly and use the qio_task_wait_thread method. This will cancel the pending idle callback and directly dispatch the task completion callback, allowing the connection to be associated with the chardev. If the background connection failed, it can still attempt a new synchronous connection. Signed-off-by: Daniel P. Berrangé <berrange@redhat.com> Message-Id: <20190211182442.8542-15-berrange@redhat.com> Signed-off-by: Marc-André Lureau <marcandre.lureau@redhat.com>
2019-02-11 19:24:40 +01:00
QIOTask *connect_task;
} SocketChardev;
#define SOCKET_CHARDEV(obj) \
OBJECT_CHECK(SocketChardev, (obj), TYPE_CHARDEV_SOCKET)
static gboolean socket_reconnect_timeout(gpointer opaque);
static void tcp_chr_telnet_init(Chardev *chr);
static void tcp_chr_change_state(SocketChardev *s, TCPChardevState state)
{
switch (state) {
case TCP_CHARDEV_STATE_DISCONNECTED:
break;
case TCP_CHARDEV_STATE_CONNECTING:
assert(s->state == TCP_CHARDEV_STATE_DISCONNECTED);
break;
case TCP_CHARDEV_STATE_CONNECTED:
assert(s->state == TCP_CHARDEV_STATE_CONNECTING);
break;
}
s->state = state;
}
static void tcp_chr_reconn_timer_cancel(SocketChardev *s)
{
if (s->reconnect_timer) {
g_source_destroy(s->reconnect_timer);
g_source_unref(s->reconnect_timer);
s->reconnect_timer = NULL;
}
}
static void qemu_chr_socket_restart_timer(Chardev *chr)
{
SocketChardev *s = SOCKET_CHARDEV(chr);
char *name;
assert(s->state == TCP_CHARDEV_STATE_DISCONNECTED);
chardev: fix race with client connections in tcp_chr_wait_connected When the 'reconnect' option is given for a client connection, the qmp_chardev_open_socket_client method will run an asynchronous connection attempt. The QIOChannel socket executes this is a single use background thread, so the connection will succeed immediately (assuming the server is listening). The chardev, however, won't get the result from this background thread until the main loop starts running and processes idle callbacks. Thus when tcp_chr_wait_connected is run s->ioc will be NULL, but the state will be TCP_CHARDEV_STATE_CONNECTING, and there may already be an established connection that will be associated with the chardev by the pending idle callback. tcp_chr_wait_connected doesn't check the state, only s->ioc, so attempts to establish another connection synchronously. If the server allows multiple connections this is unhelpful but not a fatal problem as the duplicate connection will get ignored by the tcp_chr_new_client method when it sees the state is already connected. If the server only supports a single connection, however, the tcp_chr_wait_connected method will hang forever because the server will not accept its synchronous connection attempt until the first connection is closed. To deal with this tcp_chr_wait_connected needs to synchronize with the completion of the background connection task. To do this it needs to create the QIOTask directly and use the qio_task_wait_thread method. This will cancel the pending idle callback and directly dispatch the task completion callback, allowing the connection to be associated with the chardev. If the background connection failed, it can still attempt a new synchronous connection. Signed-off-by: Daniel P. Berrangé <berrange@redhat.com> Message-Id: <20190211182442.8542-15-berrange@redhat.com> Signed-off-by: Marc-André Lureau <marcandre.lureau@redhat.com>
2019-02-11 19:24:40 +01:00
assert(!s->reconnect_timer);
name = g_strdup_printf("chardev-socket-reconnect-%s", chr->label);
s->reconnect_timer = qemu_chr_timeout_add_ms(chr,
s->reconnect_time * 1000,
socket_reconnect_timeout,
chr);
g_source_set_name(s->reconnect_timer, name);
g_free(name);
}
static void check_report_connect_error(Chardev *chr,
Error *err)
{
SocketChardev *s = SOCKET_CHARDEV(chr);
if (!s->connect_err_reported) {
error_report("Unable to connect character device %s: %s",
chr->label, error_get_pretty(err));
s->connect_err_reported = true;
}
qemu_chr_socket_restart_timer(chr);
}
static void tcp_chr_accept(QIONetListener *listener,
QIOChannelSocket *cioc,
void *opaque);
static int tcp_chr_read_poll(void *opaque);
static void tcp_chr_disconnect(Chardev *chr);
/* Called with chr_write_lock held. */
static int tcp_chr_write(Chardev *chr, const uint8_t *buf, int len)
{
SocketChardev *s = SOCKET_CHARDEV(chr);
if (s->state == TCP_CHARDEV_STATE_CONNECTED) {
int ret = io_channel_send_full(s->ioc, buf, len,
s->write_msgfds,
s->write_msgfds_num);
/* free the written msgfds in any cases
* other than ret < 0 && errno == EAGAIN
*/
if (!(ret < 0 && EAGAIN == errno)
&& s->write_msgfds_num) {
g_free(s->write_msgfds);
s->write_msgfds = 0;
s->write_msgfds_num = 0;
}
if (ret < 0 && errno != EAGAIN) {
if (tcp_chr_read_poll(chr) <= 0) {
tcp_chr_disconnect(chr);
return len;
} /* else let the read handler finish it properly */
}
return ret;
} else {
/* XXX: indicate an error ? */
return len;
}
}
static int tcp_chr_read_poll(void *opaque)
{
Chardev *chr = CHARDEV(opaque);
SocketChardev *s = SOCKET_CHARDEV(opaque);
if (s->state != TCP_CHARDEV_STATE_CONNECTED) {
return 0;
}
s->max_size = qemu_chr_be_can_write(chr);
return s->max_size;
}
static void tcp_chr_process_IAC_bytes(Chardev *chr,
SocketChardev *s,
uint8_t *buf, int *size)
{
/* Handle any telnet or tn3270 client's basic IAC options.
* For telnet options, it satisfies char by char mode with no echo.
* For tn3270 options, it satisfies binary mode with EOR.
* All IAC options will be removed from the buf and the do_opt
* pointer will be used to track the state of the width of the
* IAC information.
*
* RFC854: "All TELNET commands consist of at least a two byte sequence.
* The commands dealing with option negotiation are three byte sequences,
* the third byte being the code for the option referenced."
* "IAC BREAK", "IAC IP", "IAC NOP" and the double IAC are two bytes.
* "IAC SB", "IAC SE" and "IAC EOR" are saved to split up data boundary
* for tn3270.
* NOP, Break and Interrupt Process(IP) might be encountered during a TN3270
* session, and NOP and IP need to be done later.
*/
int i;
int j = 0;
for (i = 0; i < *size; i++) {
if (s->do_telnetopt > 1) {
if ((unsigned char)buf[i] == IAC && s->do_telnetopt == 2) {
/* Double IAC means send an IAC */
if (j != i) {
buf[j] = buf[i];
}
j++;
s->do_telnetopt = 1;
} else {
if ((unsigned char)buf[i] == IAC_BREAK
&& s->do_telnetopt == 2) {
/* Handle IAC break commands by sending a serial break */
qemu_chr_be_event(chr, CHR_EVENT_BREAK);
s->do_telnetopt++;
} else if (s->is_tn3270 && ((unsigned char)buf[i] == IAC_EOR
|| (unsigned char)buf[i] == IAC_SB
|| (unsigned char)buf[i] == IAC_SE)
&& s->do_telnetopt == 2) {
buf[j++] = IAC;
buf[j++] = buf[i];
s->do_telnetopt++;
} else if (s->is_tn3270 && ((unsigned char)buf[i] == IAC_IP
|| (unsigned char)buf[i] == IAC_NOP)
&& s->do_telnetopt == 2) {
/* TODO: IP and NOP need to be implemented later. */
s->do_telnetopt++;
}
s->do_telnetopt++;
}
if (s->do_telnetopt >= 4) {
s->do_telnetopt = 1;
}
} else {
if ((unsigned char)buf[i] == IAC) {
s->do_telnetopt = 2;
} else {
if (j != i) {
buf[j] = buf[i];
}
j++;
}
}
}
*size = j;
}
static int tcp_get_msgfds(Chardev *chr, int *fds, int num)
{
SocketChardev *s = SOCKET_CHARDEV(chr);
int to_copy = (s->read_msgfds_num < num) ? s->read_msgfds_num : num;
assert(num <= TCP_MAX_FDS);
if (to_copy) {
int i;
memcpy(fds, s->read_msgfds, to_copy * sizeof(int));
/* Close unused fds */
for (i = to_copy; i < s->read_msgfds_num; i++) {
close(s->read_msgfds[i]);
}
g_free(s->read_msgfds);
s->read_msgfds = 0;
s->read_msgfds_num = 0;
}
return to_copy;
}
static int tcp_set_msgfds(Chardev *chr, int *fds, int num)
{
SocketChardev *s = SOCKET_CHARDEV(chr);
/* clear old pending fd array */
g_free(s->write_msgfds);
s->write_msgfds = NULL;
s->write_msgfds_num = 0;
if ((s->state != TCP_CHARDEV_STATE_CONNECTED) ||
!qio_channel_has_feature(s->ioc,
QIO_CHANNEL_FEATURE_FD_PASS)) {
return -1;
}
if (num) {
s->write_msgfds = g_new(int, num);
memcpy(s->write_msgfds, fds, num * sizeof(int));
}
s->write_msgfds_num = num;
return 0;
}
static ssize_t tcp_chr_recv(Chardev *chr, char *buf, size_t len)
{
SocketChardev *s = SOCKET_CHARDEV(chr);
struct iovec iov = { .iov_base = buf, .iov_len = len };
int ret;
size_t i;
int *msgfds = NULL;
size_t msgfds_num = 0;
if (qio_channel_has_feature(s->ioc, QIO_CHANNEL_FEATURE_FD_PASS)) {
ret = qio_channel_readv_full(s->ioc, &iov, 1,
&msgfds, &msgfds_num,
NULL);
} else {
ret = qio_channel_readv_full(s->ioc, &iov, 1,
NULL, NULL,
NULL);
}
if (ret == QIO_CHANNEL_ERR_BLOCK) {
errno = EAGAIN;
ret = -1;
} else if (ret == -1) {
errno = EIO;
}
if (msgfds_num) {
/* close and clean read_msgfds */
for (i = 0; i < s->read_msgfds_num; i++) {
close(s->read_msgfds[i]);
}
if (s->read_msgfds_num) {
g_free(s->read_msgfds);
}
s->read_msgfds = msgfds;
s->read_msgfds_num = msgfds_num;
}
for (i = 0; i < s->read_msgfds_num; i++) {
int fd = s->read_msgfds[i];
if (fd < 0) {
continue;
}
/* O_NONBLOCK is preserved across SCM_RIGHTS so reset it */
qemu_set_block(fd);
#ifndef MSG_CMSG_CLOEXEC
qemu_set_cloexec(fd);
#endif
}
return ret;
}
static GSource *tcp_chr_add_watch(Chardev *chr, GIOCondition cond)
{
SocketChardev *s = SOCKET_CHARDEV(chr);
return qio_channel_create_watch(s->ioc, cond);
}
static void remove_hup_source(SocketChardev *s)
{
if (s->hup_source != NULL) {
g_source_destroy(s->hup_source);
g_source_unref(s->hup_source);
s->hup_source = NULL;
}
}
static void tcp_chr_free_connection(Chardev *chr)
{
SocketChardev *s = SOCKET_CHARDEV(chr);
int i;
if (s->read_msgfds_num) {
for (i = 0; i < s->read_msgfds_num; i++) {
close(s->read_msgfds[i]);
}
g_free(s->read_msgfds);
s->read_msgfds = NULL;
s->read_msgfds_num = 0;
}
remove_hup_source(s);
chardev/char-socket: add POLLHUP handler The following behavior was observed for QEMU configured by libvirt to use guest agent as usual for the guests without virtio-serial driver (Windows or the guest remaining in BIOS stage). In QEMU on first connect to listen character device socket the listen socket is removed from poll just after the accept(). virtio_serial_guest_ready() returns 0 and the descriptor of the connected Unix socket is removed from poll and it will not be present in poll() until the guest will initialize the driver and change the state of the serial to "guest connected". In libvirt connect() to guest agent is performed on restart and is run under VM state lock. Connect() is blocking and can wait forever. In this case libvirt can not perform ANY operation on that VM. The bug can be easily reproduced this way: Terminal 1: qemu-system-x86_64 -m 512 -device pci-serial,chardev=serial1 -chardev socket,id=serial1,path=/tmp/console.sock,server,nowait (virtio-serial and isa-serial also fit) Terminal 2: minicom -D unix\#/tmp/console.sock (type something and press enter) C-a x (to exit) Do 3 times: minicom -D unix\#/tmp/console.sock C-a x It needs 4 connections, because the first one is accepted by QEMU, then two are queued by the kernel, and the 4th blocks. The problem is that QEMU doesn't add a read watcher after succesful read until the guest device wants to acquire recieved data, so I propose to install a separate pullhup watcher regardless of whether the device waits for data or not. Signed-off-by: Klim Kireev <klim.kireev@virtuozzo.com> Message-Id: <20180125135129.9305-1-klim.kireev@virtuozzo.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2018-01-25 14:51:29 +01:00
tcp_set_msgfds(chr, NULL, 0);
remove_fd_in_watch(chr);
object_unref(OBJECT(s->sioc));
s->sioc = NULL;
object_unref(OBJECT(s->ioc));
s->ioc = NULL;
g_free(chr->filename);
chr->filename = NULL;
tcp_chr_change_state(s, TCP_CHARDEV_STATE_DISCONNECTED);
}
static const char *qemu_chr_socket_protocol(SocketChardev *s)
{
if (s->is_telnet) {
return "telnet";
}
return s->is_websock ? "websocket" : "tcp";
}
static char *qemu_chr_socket_address(SocketChardev *s, const char *prefix)
{
switch (s->addr->type) {
case SOCKET_ADDRESS_TYPE_INET:
return g_strdup_printf("%s%s:%s:%s%s", prefix,
qemu_chr_socket_protocol(s),
s->addr->u.inet.host,
s->addr->u.inet.port,
s->is_listen ? ",server" : "");
break;
case SOCKET_ADDRESS_TYPE_UNIX:
return g_strdup_printf("%sunix:%s%s", prefix,
s->addr->u.q_unix.path,
s->is_listen ? ",server" : "");
break;
case SOCKET_ADDRESS_TYPE_FD:
return g_strdup_printf("%sfd:%s%s", prefix, s->addr->u.fd.str,
s->is_listen ? ",server" : "");
break;
case SOCKET_ADDRESS_TYPE_VSOCK:
return g_strdup_printf("%svsock:%s:%s", prefix,
s->addr->u.vsock.cid,
s->addr->u.vsock.port);
default:
abort();
}
}
static void update_disconnected_filename(SocketChardev *s)
{
Chardev *chr = CHARDEV(s);
g_free(chr->filename);
if (s->addr) {
chr->filename = qemu_chr_socket_address(s, "disconnected:");
} else {
chr->filename = g_strdup("disconnected:socket");
}
}
/* NB may be called even if tcp_chr_connect has not been
* reached, due to TLS or telnet initialization failure,
* so can *not* assume s->state == TCP_CHARDEV_STATE_CONNECTED
*/
static void tcp_chr_disconnect(Chardev *chr)
{
SocketChardev *s = SOCKET_CHARDEV(chr);
bool emit_close = s->state == TCP_CHARDEV_STATE_CONNECTED;
tcp_chr_free_connection(chr);
if (s->listener) {
qio_net_listener_set_client_func_full(s->listener, tcp_chr_accept,
chr, NULL, chr->gcontext);
}
update_disconnected_filename(s);
if (emit_close) {
qemu_chr_be_event(chr, CHR_EVENT_CLOSED);
}
if (s->reconnect_time) {
qemu_chr_socket_restart_timer(chr);
}
}
static gboolean tcp_chr_read(QIOChannel *chan, GIOCondition cond, void *opaque)
{
Chardev *chr = CHARDEV(opaque);
SocketChardev *s = SOCKET_CHARDEV(opaque);
uint8_t buf[CHR_READ_BUF_LEN];
int len, size;
if ((s->state != TCP_CHARDEV_STATE_CONNECTED) ||
s->max_size <= 0) {
return TRUE;
}
len = sizeof(buf);
if (len > s->max_size) {
len = s->max_size;
}
size = tcp_chr_recv(chr, (void *)buf, len);
if (size == 0 || (size == -1 && errno != EAGAIN)) {
/* connection closed */
tcp_chr_disconnect(chr);
} else if (size > 0) {
if (s->do_telnetopt) {
tcp_chr_process_IAC_bytes(chr, s, buf, &size);
}
if (size > 0) {
qemu_chr_be_write(chr, buf, size);
}
}
return TRUE;
}
chardev/char-socket: add POLLHUP handler The following behavior was observed for QEMU configured by libvirt to use guest agent as usual for the guests without virtio-serial driver (Windows or the guest remaining in BIOS stage). In QEMU on first connect to listen character device socket the listen socket is removed from poll just after the accept(). virtio_serial_guest_ready() returns 0 and the descriptor of the connected Unix socket is removed from poll and it will not be present in poll() until the guest will initialize the driver and change the state of the serial to "guest connected". In libvirt connect() to guest agent is performed on restart and is run under VM state lock. Connect() is blocking and can wait forever. In this case libvirt can not perform ANY operation on that VM. The bug can be easily reproduced this way: Terminal 1: qemu-system-x86_64 -m 512 -device pci-serial,chardev=serial1 -chardev socket,id=serial1,path=/tmp/console.sock,server,nowait (virtio-serial and isa-serial also fit) Terminal 2: minicom -D unix\#/tmp/console.sock (type something and press enter) C-a x (to exit) Do 3 times: minicom -D unix\#/tmp/console.sock C-a x It needs 4 connections, because the first one is accepted by QEMU, then two are queued by the kernel, and the 4th blocks. The problem is that QEMU doesn't add a read watcher after succesful read until the guest device wants to acquire recieved data, so I propose to install a separate pullhup watcher regardless of whether the device waits for data or not. Signed-off-by: Klim Kireev <klim.kireev@virtuozzo.com> Message-Id: <20180125135129.9305-1-klim.kireev@virtuozzo.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2018-01-25 14:51:29 +01:00
static gboolean tcp_chr_hup(QIOChannel *channel,
GIOCondition cond,
void *opaque)
{
Chardev *chr = CHARDEV(opaque);
tcp_chr_disconnect(chr);
return G_SOURCE_REMOVE;
}
static int tcp_chr_sync_read(Chardev *chr, const uint8_t *buf, int len)
{
SocketChardev *s = SOCKET_CHARDEV(chr);
int size;
if (s->state != TCP_CHARDEV_STATE_CONNECTED) {
return 0;
}
qio_channel_set_blocking(s->ioc, true, NULL);
size = tcp_chr_recv(chr, (void *) buf, len);
qio_channel_set_blocking(s->ioc, false, NULL);
if (size == 0) {
/* connection closed */
tcp_chr_disconnect(chr);
}
return size;
}
static char *qemu_chr_compute_filename(SocketChardev *s)
{
struct sockaddr_storage *ss = &s->sioc->localAddr;
struct sockaddr_storage *ps = &s->sioc->remoteAddr;
socklen_t ss_len = s->sioc->localAddrLen;
socklen_t ps_len = s->sioc->remoteAddrLen;
char shost[NI_MAXHOST], sserv[NI_MAXSERV];
char phost[NI_MAXHOST], pserv[NI_MAXSERV];
const char *left = "", *right = "";
switch (ss->ss_family) {
#ifndef _WIN32
case AF_UNIX:
return g_strdup_printf("unix:%s%s",
((struct sockaddr_un *)(ss))->sun_path,
s->is_listen ? ",server" : "");
#endif
case AF_INET6:
left = "[";
right = "]";
/* fall through */
case AF_INET:
getnameinfo((struct sockaddr *) ss, ss_len, shost, sizeof(shost),
sserv, sizeof(sserv), NI_NUMERICHOST | NI_NUMERICSERV);
getnameinfo((struct sockaddr *) ps, ps_len, phost, sizeof(phost),
pserv, sizeof(pserv), NI_NUMERICHOST | NI_NUMERICSERV);
return g_strdup_printf("%s:%s%s%s:%s%s <-> %s%s%s:%s",
qemu_chr_socket_protocol(s),
left, shost, right, sserv,
s->is_listen ? ",server" : "",
left, phost, right, pserv);
default:
return g_strdup_printf("unknown");
}
}
static void update_ioc_handlers(SocketChardev *s)
{
Chardev *chr = CHARDEV(s);
if (s->state != TCP_CHARDEV_STATE_CONNECTED) {
return;
}
remove_fd_in_watch(chr);
chr->gsource = io_add_watch_poll(chr, s->ioc,
tcp_chr_read_poll,
tcp_chr_read, chr,
chr->gcontext);
remove_hup_source(s);
s->hup_source = qio_channel_create_watch(s->ioc, G_IO_HUP);
g_source_set_callback(s->hup_source, (GSourceFunc)tcp_chr_hup,
chr, NULL);
g_source_attach(s->hup_source, chr->gcontext);
}
static void tcp_chr_connect(void *opaque)
{
Chardev *chr = CHARDEV(opaque);
SocketChardev *s = SOCKET_CHARDEV(opaque);
g_free(chr->filename);
chr->filename = qemu_chr_compute_filename(s);
tcp_chr_change_state(s, TCP_CHARDEV_STATE_CONNECTED);
update_ioc_handlers(s);
qemu_chr_be_event(chr, CHR_EVENT_OPENED);
}
static void tcp_chr_telnet_destroy(SocketChardev *s)
{
if (s->telnet_source) {
g_source_destroy(s->telnet_source);
g_source_unref(s->telnet_source);
s->telnet_source = NULL;
}
}
static void tcp_chr_update_read_handler(Chardev *chr)
{
SocketChardev *s = SOCKET_CHARDEV(chr);
if (s->listener && s->state == TCP_CHARDEV_STATE_DISCONNECTED) {
/*
* It's possible that chardev context is changed in
* qemu_chr_be_update_read_handlers(). Reset it for QIO net
* listener if there is.
*/
qio_net_listener_set_client_func_full(s->listener, tcp_chr_accept,
chr, NULL, chr->gcontext);
}
if (s->telnet_source) {
tcp_chr_telnet_init(CHARDEV(s));
}
update_ioc_handlers(s);
}
static gboolean tcp_chr_telnet_init_io(QIOChannel *ioc,
GIOCondition cond G_GNUC_UNUSED,
gpointer user_data)
{
SocketChardev *s = user_data;
Chardev *chr = CHARDEV(s);
TCPChardevTelnetInit *init = s->telnet_init;
ssize_t ret;
assert(init);
ret = qio_channel_write(ioc, init->buf, init->buflen, NULL);
if (ret < 0) {
if (ret == QIO_CHANNEL_ERR_BLOCK) {
ret = 0;
} else {
tcp_chr_disconnect(chr);
goto end;
}
}
init->buflen -= ret;
if (init->buflen == 0) {
tcp_chr_connect(chr);
goto end;
}
memmove(init->buf, init->buf + ret, init->buflen);
return G_SOURCE_CONTINUE;
end:
g_free(s->telnet_init);
s->telnet_init = NULL;
g_source_unref(s->telnet_source);
s->telnet_source = NULL;
return G_SOURCE_REMOVE;
}
static void tcp_chr_telnet_init(Chardev *chr)
{
SocketChardev *s = SOCKET_CHARDEV(chr);
TCPChardevTelnetInit *init;
size_t n = 0;
/* Destroy existing task */
tcp_chr_telnet_destroy(s);
if (s->telnet_init) {
/* We are possibly during a handshake already */
goto cont;
}
s->telnet_init = g_new0(TCPChardevTelnetInit, 1);
init = s->telnet_init;
#define IACSET(x, a, b, c) \
do { \
x[n++] = a; \
x[n++] = b; \
x[n++] = c; \
} while (0)
if (!s->is_tn3270) {
init->buflen = 12;
/* Prep the telnet negotion to put telnet in binary,
* no echo, single char mode */
IACSET(init->buf, 0xff, 0xfb, 0x01); /* IAC WILL ECHO */
IACSET(init->buf, 0xff, 0xfb, 0x03); /* IAC WILL Suppress go ahead */
IACSET(init->buf, 0xff, 0xfb, 0x00); /* IAC WILL Binary */
IACSET(init->buf, 0xff, 0xfd, 0x00); /* IAC DO Binary */
} else {
init->buflen = 21;
/* Prep the TN3270 negotion based on RFC1576 */
IACSET(init->buf, 0xff, 0xfd, 0x19); /* IAC DO EOR */
IACSET(init->buf, 0xff, 0xfb, 0x19); /* IAC WILL EOR */
IACSET(init->buf, 0xff, 0xfd, 0x00); /* IAC DO BINARY */
IACSET(init->buf, 0xff, 0xfb, 0x00); /* IAC WILL BINARY */
IACSET(init->buf, 0xff, 0xfd, 0x18); /* IAC DO TERMINAL TYPE */
IACSET(init->buf, 0xff, 0xfa, 0x18); /* IAC SB TERMINAL TYPE */
IACSET(init->buf, 0x01, 0xff, 0xf0); /* SEND IAC SE */
}
#undef IACSET
cont:
s->telnet_source = qio_channel_add_watch_source(s->ioc, G_IO_OUT,
tcp_chr_telnet_init_io,
s, NULL,
chr->gcontext);
}
static void tcp_chr_websock_handshake(QIOTask *task, gpointer user_data)
{
Chardev *chr = user_data;
SocketChardev *s = user_data;
if (qio_task_propagate_error(task, NULL)) {
tcp_chr_disconnect(chr);
} else {
if (s->do_telnetopt) {
tcp_chr_telnet_init(chr);
} else {
tcp_chr_connect(chr);
}
}
}
static void tcp_chr_websock_init(Chardev *chr)
{
SocketChardev *s = SOCKET_CHARDEV(chr);
QIOChannelWebsock *wioc = NULL;
gchar *name;
wioc = qio_channel_websock_new_server(s->ioc);
name = g_strdup_printf("chardev-websocket-server-%s", chr->label);
qio_channel_set_name(QIO_CHANNEL(wioc), name);
g_free(name);
object_unref(OBJECT(s->ioc));
s->ioc = QIO_CHANNEL(wioc);
qio_channel_websock_handshake(wioc, tcp_chr_websock_handshake, chr, NULL);
}
static void tcp_chr_tls_handshake(QIOTask *task,
gpointer user_data)
{
Chardev *chr = user_data;
SocketChardev *s = user_data;
if (qio_task_propagate_error(task, NULL)) {
tcp_chr_disconnect(chr);
} else {
if (s->is_websock) {
tcp_chr_websock_init(chr);
} else if (s->do_telnetopt) {
tcp_chr_telnet_init(chr);
} else {
tcp_chr_connect(chr);
}
}
}
static void tcp_chr_tls_init(Chardev *chr)
{
SocketChardev *s = SOCKET_CHARDEV(chr);
QIOChannelTLS *tioc;
Error *err = NULL;
gchar *name;
if (s->is_listen) {
tioc = qio_channel_tls_new_server(
s->ioc, s->tls_creds,
s->tls_authz,
&err);
} else {
tioc = qio_channel_tls_new_client(
s->ioc, s->tls_creds,
s->addr->u.inet.host,
&err);
}
if (tioc == NULL) {
error_free(err);
tcp_chr_disconnect(chr);
return;
}
name = g_strdup_printf("chardev-tls-%s-%s",
s->is_listen ? "server" : "client",
chr->label);
qio_channel_set_name(QIO_CHANNEL(tioc), name);
g_free(name);
object_unref(OBJECT(s->ioc));
s->ioc = QIO_CHANNEL(tioc);
qio_channel_tls_handshake(tioc,
tcp_chr_tls_handshake,
chr,
NULL,
chr->gcontext);
}
static void tcp_chr_set_client_ioc_name(Chardev *chr,
QIOChannelSocket *sioc)
{
SocketChardev *s = SOCKET_CHARDEV(chr);
char *name;
name = g_strdup_printf("chardev-tcp-%s-%s",
s->is_listen ? "server" : "client",
chr->label);
qio_channel_set_name(QIO_CHANNEL(sioc), name);
g_free(name);
}
static int tcp_chr_new_client(Chardev *chr, QIOChannelSocket *sioc)
{
SocketChardev *s = SOCKET_CHARDEV(chr);
if (s->state != TCP_CHARDEV_STATE_CONNECTING) {
return -1;
}
s->ioc = QIO_CHANNEL(sioc);
object_ref(OBJECT(sioc));
s->sioc = sioc;
object_ref(OBJECT(sioc));
qio_channel_set_blocking(s->ioc, false, NULL);
if (s->do_nodelay) {
qio_channel_set_delay(s->ioc, false);
}
if (s->listener) {
qio_net_listener_set_client_func_full(s->listener, NULL, NULL,
NULL, chr->gcontext);
}
if (s->tls_creds) {
tcp_chr_tls_init(chr);
} else if (s->is_websock) {
tcp_chr_websock_init(chr);
} else if (s->do_telnetopt) {
tcp_chr_telnet_init(chr);
} else {
tcp_chr_connect(chr);
}
return 0;
}
static int tcp_chr_add_client(Chardev *chr, int fd)
{
int ret;
QIOChannelSocket *sioc;
SocketChardev *s = SOCKET_CHARDEV(chr);
if (s->state != TCP_CHARDEV_STATE_DISCONNECTED) {
return -1;
}
sioc = qio_channel_socket_new_fd(fd, NULL);
if (!sioc) {
return -1;
}
tcp_chr_change_state(s, TCP_CHARDEV_STATE_CONNECTING);
tcp_chr_set_client_ioc_name(chr, sioc);
ret = tcp_chr_new_client(chr, sioc);
object_unref(OBJECT(sioc));
return ret;
}
static void tcp_chr_accept(QIONetListener *listener,
QIOChannelSocket *cioc,
void *opaque)
{
Chardev *chr = CHARDEV(opaque);
SocketChardev *s = SOCKET_CHARDEV(chr);
tcp_chr_change_state(s, TCP_CHARDEV_STATE_CONNECTING);
tcp_chr_set_client_ioc_name(chr, cioc);
tcp_chr_new_client(chr, cioc);
}
static int tcp_chr_connect_client_sync(Chardev *chr, Error **errp)
{
SocketChardev *s = SOCKET_CHARDEV(chr);
QIOChannelSocket *sioc = qio_channel_socket_new();
tcp_chr_change_state(s, TCP_CHARDEV_STATE_CONNECTING);
tcp_chr_set_client_ioc_name(chr, sioc);
if (qio_channel_socket_connect_sync(sioc, s->addr, errp) < 0) {
tcp_chr_change_state(s, TCP_CHARDEV_STATE_DISCONNECTED);
object_unref(OBJECT(sioc));
return -1;
}
tcp_chr_new_client(chr, sioc);
object_unref(OBJECT(sioc));
return 0;
}
static void tcp_chr_accept_server_sync(Chardev *chr)
{
SocketChardev *s = SOCKET_CHARDEV(chr);
QIOChannelSocket *sioc;
info_report("QEMU waiting for connection on: %s",
chr->filename);
tcp_chr_change_state(s, TCP_CHARDEV_STATE_CONNECTING);
sioc = qio_net_listener_wait_client(s->listener);
tcp_chr_set_client_ioc_name(chr, sioc);
tcp_chr_new_client(chr, sioc);
object_unref(OBJECT(sioc));
}
static int tcp_chr_wait_connected(Chardev *chr, Error **errp)
{
SocketChardev *s = SOCKET_CHARDEV(chr);
chardev: disallow TLS/telnet/websocket with tcp_chr_wait_connected In the previous commit commit 1dc8a6695c731abb7461c637b2512c3670d82be4 Author: Marc-André Lureau <marcandre.lureau@redhat.com> Date: Tue Aug 16 12:33:32 2016 +0400 char: fix waiting for TLS and telnet connection the tcp_chr_wait_connected() method was changed to check for a non-NULL 's->ioc' as a sign that there is already a connection present, as opposed to checking the "connected" flag to supposedly fix handling of TLS/telnet connections. The original code would repeatedly call tcp_chr_wait_connected creating many connections as 'connected' would never become true. The changed code would still repeatedly call tcp_chr_wait_connected busy waiting because s->ioc is set but the chardev will never see CHR_EVENT_OPENED. IOW, the code is still broken with TLS/telnet, but in a different way. Checking for a non-NULL 's->ioc' does not mean that a CHR_EVENT_OPENED will be ready for a TLS/telnet connection. These protocols (and the websocket protocol) all require the main loop to be running in order to complete the protocol handshake before emitting CHR_EVENT_OPENED. The tcp_chr_wait_connected() method is only used during early startup before a main loop is running, so TLS/telnet/websock connections can never complete initialization. Making this work would require changing tcp_chr_wait_connected to run a main loop. This is quite complex since we must not allow GSource's that other parts of QEMU have registered to run yet. The current callers of tcp_chr_wait_connected do not require use of the TLS/telnet/websocket protocols, so the simplest option is to just forbid this combination completely for now. Reviewed-by: Marc-André Lureau <marcandre.lureau@redhat.com> Signed-off-by: Daniel P. Berrangé <berrange@redhat.com> Message-Id: <20190211182442.8542-14-berrange@redhat.com> Signed-off-by: Marc-André Lureau <marcandre.lureau@redhat.com>
2019-02-11 19:24:39 +01:00
const char *opts[] = { "telnet", "tn3270", "websock", "tls-creds" };
bool optset[] = { s->is_telnet, s->is_tn3270, s->is_websock, s->tls_creds };
size_t i;
QEMU_BUILD_BUG_ON(G_N_ELEMENTS(opts) != G_N_ELEMENTS(optset));
for (i = 0; i < G_N_ELEMENTS(opts); i++) {
if (optset[i]) {
error_setg(errp,
"'%s' option is incompatible with waiting for "
"connection completion", opts[i]);
return -1;
}
}
chardev: fix race with client connections in tcp_chr_wait_connected When the 'reconnect' option is given for a client connection, the qmp_chardev_open_socket_client method will run an asynchronous connection attempt. The QIOChannel socket executes this is a single use background thread, so the connection will succeed immediately (assuming the server is listening). The chardev, however, won't get the result from this background thread until the main loop starts running and processes idle callbacks. Thus when tcp_chr_wait_connected is run s->ioc will be NULL, but the state will be TCP_CHARDEV_STATE_CONNECTING, and there may already be an established connection that will be associated with the chardev by the pending idle callback. tcp_chr_wait_connected doesn't check the state, only s->ioc, so attempts to establish another connection synchronously. If the server allows multiple connections this is unhelpful but not a fatal problem as the duplicate connection will get ignored by the tcp_chr_new_client method when it sees the state is already connected. If the server only supports a single connection, however, the tcp_chr_wait_connected method will hang forever because the server will not accept its synchronous connection attempt until the first connection is closed. To deal with this tcp_chr_wait_connected needs to synchronize with the completion of the background connection task. To do this it needs to create the QIOTask directly and use the qio_task_wait_thread method. This will cancel the pending idle callback and directly dispatch the task completion callback, allowing the connection to be associated with the chardev. If the background connection failed, it can still attempt a new synchronous connection. Signed-off-by: Daniel P. Berrangé <berrange@redhat.com> Message-Id: <20190211182442.8542-15-berrange@redhat.com> Signed-off-by: Marc-André Lureau <marcandre.lureau@redhat.com>
2019-02-11 19:24:40 +01:00
tcp_chr_reconn_timer_cancel(s);
/*
* We expect states to be as follows:
*
* - server
* - wait -> CONNECTED
* - nowait -> DISCONNECTED
* - client
* - reconnect == 0 -> CONNECTED
* - reconnect != 0 -> CONNECTING
*
*/
if (s->state == TCP_CHARDEV_STATE_CONNECTING) {
if (!s->connect_task) {
error_setg(errp,
"Unexpected 'connecting' state without connect task "
"while waiting for connection completion");
return -1;
}
/*
* tcp_chr_wait_connected should only ever be run from the
* main loop thread associated with chr->gcontext, otherwise
* qio_task_wait_thread has a dangerous race condition with
* free'ing of the s->connect_task object.
*
* Acquiring the main context doesn't 100% prove we're in
* the main loop thread, but it does at least guarantee
* that the main loop won't be executed by another thread
* avoiding the race condition with the task idle callback.
*/
g_main_context_acquire(chr->gcontext);
qio_task_wait_thread(s->connect_task);
g_main_context_release(chr->gcontext);
/*
* The completion callback (qemu_chr_socket_connected) for
* s->connect_task should have set this to NULL by the time
* qio_task_wait_thread has returned.
*/
assert(!s->connect_task);
/*
* NB we are *not* guaranteed to have "s->state == ..CONNECTED"
* at this point as this first connect may be failed, so
* allow the next loop to run regardless.
*/
}
while (s->state != TCP_CHARDEV_STATE_CONNECTED) {
if (s->is_listen) {
tcp_chr_accept_server_sync(chr);
} else {
Error *err = NULL;
if (tcp_chr_connect_client_sync(chr, &err) < 0) {
if (s->reconnect_time) {
error_free(err);
g_usleep(s->reconnect_time * 1000ULL * 1000ULL);
} else {
error_propagate(errp, err);
return -1;
}
}
}
}
return 0;
}
static void char_socket_finalize(Object *obj)
{
Chardev *chr = CHARDEV(obj);
SocketChardev *s = SOCKET_CHARDEV(obj);
tcp_chr_free_connection(chr);
tcp_chr_reconn_timer_cancel(s);
qapi_free_SocketAddress(s->addr);
tcp_chr_telnet_destroy(s);
g_free(s->telnet_init);
if (s->listener) {
qio_net_listener_set_client_func_full(s->listener, NULL, NULL,
NULL, chr->gcontext);
object_unref(OBJECT(s->listener));
}
if (s->tls_creds) {
object_unref(OBJECT(s->tls_creds));
}
g_free(s->tls_authz);
qemu_chr_be_event(chr, CHR_EVENT_CLOSED);
}
static void qemu_chr_socket_connected(QIOTask *task, void *opaque)
{
QIOChannelSocket *sioc = QIO_CHANNEL_SOCKET(qio_task_get_source(task));
Chardev *chr = CHARDEV(opaque);
SocketChardev *s = SOCKET_CHARDEV(chr);
Error *err = NULL;
chardev: fix race with client connections in tcp_chr_wait_connected When the 'reconnect' option is given for a client connection, the qmp_chardev_open_socket_client method will run an asynchronous connection attempt. The QIOChannel socket executes this is a single use background thread, so the connection will succeed immediately (assuming the server is listening). The chardev, however, won't get the result from this background thread until the main loop starts running and processes idle callbacks. Thus when tcp_chr_wait_connected is run s->ioc will be NULL, but the state will be TCP_CHARDEV_STATE_CONNECTING, and there may already be an established connection that will be associated with the chardev by the pending idle callback. tcp_chr_wait_connected doesn't check the state, only s->ioc, so attempts to establish another connection synchronously. If the server allows multiple connections this is unhelpful but not a fatal problem as the duplicate connection will get ignored by the tcp_chr_new_client method when it sees the state is already connected. If the server only supports a single connection, however, the tcp_chr_wait_connected method will hang forever because the server will not accept its synchronous connection attempt until the first connection is closed. To deal with this tcp_chr_wait_connected needs to synchronize with the completion of the background connection task. To do this it needs to create the QIOTask directly and use the qio_task_wait_thread method. This will cancel the pending idle callback and directly dispatch the task completion callback, allowing the connection to be associated with the chardev. If the background connection failed, it can still attempt a new synchronous connection. Signed-off-by: Daniel P. Berrangé <berrange@redhat.com> Message-Id: <20190211182442.8542-15-berrange@redhat.com> Signed-off-by: Marc-André Lureau <marcandre.lureau@redhat.com>
2019-02-11 19:24:40 +01:00
s->connect_task = NULL;
if (qio_task_propagate_error(task, &err)) {
tcp_chr_change_state(s, TCP_CHARDEV_STATE_DISCONNECTED);
check_report_connect_error(chr, err);
error_free(err);
goto cleanup;
}
s->connect_err_reported = false;
tcp_chr_new_client(chr, sioc);
cleanup:
object_unref(OBJECT(sioc));
}
chardev: fix race with client connections in tcp_chr_wait_connected When the 'reconnect' option is given for a client connection, the qmp_chardev_open_socket_client method will run an asynchronous connection attempt. The QIOChannel socket executes this is a single use background thread, so the connection will succeed immediately (assuming the server is listening). The chardev, however, won't get the result from this background thread until the main loop starts running and processes idle callbacks. Thus when tcp_chr_wait_connected is run s->ioc will be NULL, but the state will be TCP_CHARDEV_STATE_CONNECTING, and there may already be an established connection that will be associated with the chardev by the pending idle callback. tcp_chr_wait_connected doesn't check the state, only s->ioc, so attempts to establish another connection synchronously. If the server allows multiple connections this is unhelpful but not a fatal problem as the duplicate connection will get ignored by the tcp_chr_new_client method when it sees the state is already connected. If the server only supports a single connection, however, the tcp_chr_wait_connected method will hang forever because the server will not accept its synchronous connection attempt until the first connection is closed. To deal with this tcp_chr_wait_connected needs to synchronize with the completion of the background connection task. To do this it needs to create the QIOTask directly and use the qio_task_wait_thread method. This will cancel the pending idle callback and directly dispatch the task completion callback, allowing the connection to be associated with the chardev. If the background connection failed, it can still attempt a new synchronous connection. Signed-off-by: Daniel P. Berrangé <berrange@redhat.com> Message-Id: <20190211182442.8542-15-berrange@redhat.com> Signed-off-by: Marc-André Lureau <marcandre.lureau@redhat.com>
2019-02-11 19:24:40 +01:00
static void tcp_chr_connect_client_task(QIOTask *task,
gpointer opaque)
{
QIOChannelSocket *ioc = QIO_CHANNEL_SOCKET(qio_task_get_source(task));
SocketAddress *addr = opaque;
Error *err = NULL;
qio_channel_socket_connect_sync(ioc, addr, &err);
qio_task_set_error(task, err);
}
static void tcp_chr_connect_client_async(Chardev *chr)
{
SocketChardev *s = SOCKET_CHARDEV(chr);
QIOChannelSocket *sioc;
tcp_chr_change_state(s, TCP_CHARDEV_STATE_CONNECTING);
sioc = qio_channel_socket_new();
tcp_chr_set_client_ioc_name(chr, sioc);
chardev: fix race with client connections in tcp_chr_wait_connected When the 'reconnect' option is given for a client connection, the qmp_chardev_open_socket_client method will run an asynchronous connection attempt. The QIOChannel socket executes this is a single use background thread, so the connection will succeed immediately (assuming the server is listening). The chardev, however, won't get the result from this background thread until the main loop starts running and processes idle callbacks. Thus when tcp_chr_wait_connected is run s->ioc will be NULL, but the state will be TCP_CHARDEV_STATE_CONNECTING, and there may already be an established connection that will be associated with the chardev by the pending idle callback. tcp_chr_wait_connected doesn't check the state, only s->ioc, so attempts to establish another connection synchronously. If the server allows multiple connections this is unhelpful but not a fatal problem as the duplicate connection will get ignored by the tcp_chr_new_client method when it sees the state is already connected. If the server only supports a single connection, however, the tcp_chr_wait_connected method will hang forever because the server will not accept its synchronous connection attempt until the first connection is closed. To deal with this tcp_chr_wait_connected needs to synchronize with the completion of the background connection task. To do this it needs to create the QIOTask directly and use the qio_task_wait_thread method. This will cancel the pending idle callback and directly dispatch the task completion callback, allowing the connection to be associated with the chardev. If the background connection failed, it can still attempt a new synchronous connection. Signed-off-by: Daniel P. Berrangé <berrange@redhat.com> Message-Id: <20190211182442.8542-15-berrange@redhat.com> Signed-off-by: Marc-André Lureau <marcandre.lureau@redhat.com>
2019-02-11 19:24:40 +01:00
/*
* Normally code would use the qio_channel_socket_connect_async
* method which uses a QIOTask + qio_task_set_error internally
* to avoid blocking. The tcp_chr_wait_connected method, however,
* needs a way to synchronize with completion of the background
* connect task which can't be done with the QIOChannelSocket
* async APIs. Thus we must use QIOTask directly to implement
* the non-blocking concept locally.
*/
s->connect_task = qio_task_new(OBJECT(sioc),
qemu_chr_socket_connected,
chr, NULL);
qio_task_run_in_thread(s->connect_task,
tcp_chr_connect_client_task,
s->addr,
NULL,
chr->gcontext);
}
static gboolean socket_reconnect_timeout(gpointer opaque)
{
Chardev *chr = CHARDEV(opaque);
SocketChardev *s = SOCKET_CHARDEV(opaque);
g_source_unref(s->reconnect_timer);
s->reconnect_timer = NULL;
if (chr->be_open) {
return false;
}
tcp_chr_connect_client_async(chr);
return false;
}
static int qmp_chardev_open_socket_server(Chardev *chr,
bool is_telnet,
bool is_waitconnect,
Error **errp)
{
SocketChardev *s = SOCKET_CHARDEV(chr);
char *name;
if (is_telnet) {
s->do_telnetopt = 1;
}
s->listener = qio_net_listener_new();
name = g_strdup_printf("chardev-tcp-listener-%s", chr->label);
qio_net_listener_set_name(s->listener, name);
g_free(name);
if (qio_net_listener_open_sync(s->listener, s->addr, errp) < 0) {
object_unref(OBJECT(s->listener));
s->listener = NULL;
return -1;
}
qapi_free_SocketAddress(s->addr);
s->addr = socket_local_address(s->listener->sioc[0]->fd, errp);
update_disconnected_filename(s);
if (is_waitconnect) {
tcp_chr_accept_server_sync(chr);
} else {
qio_net_listener_set_client_func_full(s->listener,
tcp_chr_accept,
chr, NULL,
chr->gcontext);
}
return 0;
}
static int qmp_chardev_open_socket_client(Chardev *chr,
int64_t reconnect,
Error **errp)
{
SocketChardev *s = SOCKET_CHARDEV(chr);
if (reconnect > 0) {
s->reconnect_time = reconnect;
tcp_chr_connect_client_async(chr);
return 0;
} else {
return tcp_chr_connect_client_sync(chr, errp);
}
}
static bool qmp_chardev_validate_socket(ChardevSocket *sock,
SocketAddress *addr,
Error **errp)
{
/* Validate any options which have a dependency on address type */
switch (addr->type) {
case SOCKET_ADDRESS_TYPE_FD:
if (sock->has_reconnect) {
error_setg(errp,
"'reconnect' option is incompatible with "
"'fd' address type");
return false;
}
if (sock->has_tls_creds &&
!(sock->has_server && sock->server)) {
error_setg(errp,
"'tls_creds' option is incompatible with "
"'fd' address type as client");
return false;
}
break;
case SOCKET_ADDRESS_TYPE_UNIX:
if (sock->has_tls_creds) {
error_setg(errp,
"'tls_creds' option is incompatible with "
"'unix' address type");
return false;
}
break;
case SOCKET_ADDRESS_TYPE_INET:
break;
case SOCKET_ADDRESS_TYPE_VSOCK:
if (sock->has_tls_creds) {
error_setg(errp,
"'tls_creds' option is incompatible with "
"'vsock' address type");
return false;
}
default:
break;
}
if (sock->has_tls_authz && !sock->has_tls_creds) {
error_setg(errp, "'tls_authz' option requires 'tls_creds' option");
return false;
}
/* Validate any options which have a dependancy on client vs server */
if (!sock->has_server || sock->server) {
if (sock->has_reconnect) {
error_setg(errp,
"'reconnect' option is incompatible with "
"socket in server listen mode");
return false;
}
} else {
if (sock->has_websocket && sock->websocket) {
error_setg(errp, "%s", "Websocket client is not implemented");
return false;
}
if (sock->has_wait) {
error_setg(errp, "%s",
"'wait' option is incompatible with "
"socket in client connect mode");
return false;
}
}
return true;
}
static void qmp_chardev_open_socket(Chardev *chr,
ChardevBackend *backend,
bool *be_opened,
Error **errp)
{
SocketChardev *s = SOCKET_CHARDEV(chr);
ChardevSocket *sock = backend->u.socket.data;
bool do_nodelay = sock->has_nodelay ? sock->nodelay : false;
bool is_listen = sock->has_server ? sock->server : true;
bool is_telnet = sock->has_telnet ? sock->telnet : false;
bool is_tn3270 = sock->has_tn3270 ? sock->tn3270 : false;
bool is_waitconnect = sock->has_wait ? sock->wait : false;
bool is_websock = sock->has_websocket ? sock->websocket : false;
int64_t reconnect = sock->has_reconnect ? sock->reconnect : 0;
SocketAddress *addr;
s->is_listen = is_listen;
s->is_telnet = is_telnet;
s->is_tn3270 = is_tn3270;
s->is_websock = is_websock;
s->do_nodelay = do_nodelay;
if (sock->tls_creds) {
Object *creds;
creds = object_resolve_path_component(
object_get_objects_root(), sock->tls_creds);
if (!creds) {
error_setg(errp, "No TLS credentials with id '%s'",
sock->tls_creds);
return;
}
s->tls_creds = (QCryptoTLSCreds *)
object_dynamic_cast(creds,
TYPE_QCRYPTO_TLS_CREDS);
if (!s->tls_creds) {
error_setg(errp, "Object with id '%s' is not TLS credentials",
sock->tls_creds);
return;
}
object_ref(OBJECT(s->tls_creds));
if (is_listen) {
if (s->tls_creds->endpoint != QCRYPTO_TLS_CREDS_ENDPOINT_SERVER) {
error_setg(errp, "%s",
"Expected TLS credentials for server endpoint");
return;
}
} else {
if (s->tls_creds->endpoint != QCRYPTO_TLS_CREDS_ENDPOINT_CLIENT) {
error_setg(errp, "%s",
"Expected TLS credentials for client endpoint");
return;
}
}
}
s->tls_authz = g_strdup(sock->tls_authz);
s->addr = addr = socket_address_flatten(sock->addr);
if (!qmp_chardev_validate_socket(sock, addr, errp)) {
return;
}
qemu_chr_set_feature(chr, QEMU_CHAR_FEATURE_RECONNECTABLE);
/* TODO SOCKET_ADDRESS_FD where fd has AF_UNIX */
if (addr->type == SOCKET_ADDRESS_TYPE_UNIX) {
qemu_chr_set_feature(chr, QEMU_CHAR_FEATURE_FD_PASS);
}
/* be isn't opened until we get a connection */
*be_opened = false;
update_disconnected_filename(s);
if (s->is_listen) {
if (qmp_chardev_open_socket_server(chr, is_telnet || is_tn3270,
is_waitconnect, errp) < 0) {
return;
}
} else {
if (qmp_chardev_open_socket_client(chr, reconnect, errp) < 0) {
return;
}
}
}
static void qemu_chr_parse_socket(QemuOpts *opts, ChardevBackend *backend,
Error **errp)
{
const char *path = qemu_opt_get(opts, "path");
const char *host = qemu_opt_get(opts, "host");
const char *port = qemu_opt_get(opts, "port");
char: allow passing pre-opened socket file descriptor at startup When starting QEMU management apps will usually setup a monitor socket, and then open it immediately after startup. If not using QEMU's own -daemonize arg, this process can be troublesome to handle correctly. The mgmt app will need to repeatedly call connect() until it succeeds, because it does not know when QEMU has created the listener socket. If can't retry connect() forever though, because an error might have caused QEMU to exit before it even creates the monitor. The obvious way to fix this kind of problem is to just pass in a pre-opened socket file descriptor for the QEMU monitor to listen on. The management app can now immediately call connect() just once. If connect() fails it knows that QEMU has exited with an error. The SocketAddress(Legacy) structs allow for FD passing via the monitor, and now via inherited file descriptors from the process that spawned QEMU. The final missing piece is adding a 'fd' parameter in the socket chardev options. This allows both HMP usage, pass any FD number with SCM_RIGHTS, then running HMP commands: getfd myfd chardev-add socket,fd=myfd Note that numeric FDs cannot be referenced directly in HMP, only named FDs. And also CLI usage, by leak FD 3 from parent by clearing O_CLOEXEC, then spawning QEMU with -chardev socket,fd=3,id=mon -mon chardev=mon,mode=control Note that named FDs cannot be referenced in CLI args, only numeric FDs. We do not wire this up in the legacy chardev syntax, so you cannot use FD passing with '-qmp', you must use the modern '-mon' + '-chardev' pair. When passing pre-opened FDs there is a restriction on use of TLS encryption. It can be used on a server socket chardev, but cannot be used for a client socket chardev. This is because when validating a server's certificate, the client needs to have a hostname available to match against the certificate identity. An illustrative example of usage is: #!/usr/bin/perl use IO::Socket::UNIX; use Fcntl; unlink "/tmp/qmp"; my $srv = IO::Socket::UNIX->new( Type => SOCK_STREAM(), Local => "/tmp/qmp", Listen => 1, ); my $flags = fcntl $srv, F_GETFD, 0; fcntl $srv, F_SETFD, $flags & ~FD_CLOEXEC; my $fd = $srv->fileno(); exec "qemu-system-x86_64", \ "-chardev", "socket,fd=$fd,server,nowait,id=mon", \ "-mon", "chardev=mon,mode=control"; Reviewed-by: Eric Blake <eblake@redhat.com> Signed-off-by: Daniel P. Berrange <berrange@redhat.com>
2017-12-21 13:57:54 +01:00
const char *fd = qemu_opt_get(opts, "fd");
SocketAddressLegacy *addr;
ChardevSocket *sock;
char: allow passing pre-opened socket file descriptor at startup When starting QEMU management apps will usually setup a monitor socket, and then open it immediately after startup. If not using QEMU's own -daemonize arg, this process can be troublesome to handle correctly. The mgmt app will need to repeatedly call connect() until it succeeds, because it does not know when QEMU has created the listener socket. If can't retry connect() forever though, because an error might have caused QEMU to exit before it even creates the monitor. The obvious way to fix this kind of problem is to just pass in a pre-opened socket file descriptor for the QEMU monitor to listen on. The management app can now immediately call connect() just once. If connect() fails it knows that QEMU has exited with an error. The SocketAddress(Legacy) structs allow for FD passing via the monitor, and now via inherited file descriptors from the process that spawned QEMU. The final missing piece is adding a 'fd' parameter in the socket chardev options. This allows both HMP usage, pass any FD number with SCM_RIGHTS, then running HMP commands: getfd myfd chardev-add socket,fd=myfd Note that numeric FDs cannot be referenced directly in HMP, only named FDs. And also CLI usage, by leak FD 3 from parent by clearing O_CLOEXEC, then spawning QEMU with -chardev socket,fd=3,id=mon -mon chardev=mon,mode=control Note that named FDs cannot be referenced in CLI args, only numeric FDs. We do not wire this up in the legacy chardev syntax, so you cannot use FD passing with '-qmp', you must use the modern '-mon' + '-chardev' pair. When passing pre-opened FDs there is a restriction on use of TLS encryption. It can be used on a server socket chardev, but cannot be used for a client socket chardev. This is because when validating a server's certificate, the client needs to have a hostname available to match against the certificate identity. An illustrative example of usage is: #!/usr/bin/perl use IO::Socket::UNIX; use Fcntl; unlink "/tmp/qmp"; my $srv = IO::Socket::UNIX->new( Type => SOCK_STREAM(), Local => "/tmp/qmp", Listen => 1, ); my $flags = fcntl $srv, F_GETFD, 0; fcntl $srv, F_SETFD, $flags & ~FD_CLOEXEC; my $fd = $srv->fileno(); exec "qemu-system-x86_64", \ "-chardev", "socket,fd=$fd,server,nowait,id=mon", \ "-mon", "chardev=mon,mode=control"; Reviewed-by: Eric Blake <eblake@redhat.com> Signed-off-by: Daniel P. Berrange <berrange@redhat.com>
2017-12-21 13:57:54 +01:00
if ((!!path + !!fd + !!host) != 1) {
error_setg(errp,
char: allow passing pre-opened socket file descriptor at startup When starting QEMU management apps will usually setup a monitor socket, and then open it immediately after startup. If not using QEMU's own -daemonize arg, this process can be troublesome to handle correctly. The mgmt app will need to repeatedly call connect() until it succeeds, because it does not know when QEMU has created the listener socket. If can't retry connect() forever though, because an error might have caused QEMU to exit before it even creates the monitor. The obvious way to fix this kind of problem is to just pass in a pre-opened socket file descriptor for the QEMU monitor to listen on. The management app can now immediately call connect() just once. If connect() fails it knows that QEMU has exited with an error. The SocketAddress(Legacy) structs allow for FD passing via the monitor, and now via inherited file descriptors from the process that spawned QEMU. The final missing piece is adding a 'fd' parameter in the socket chardev options. This allows both HMP usage, pass any FD number with SCM_RIGHTS, then running HMP commands: getfd myfd chardev-add socket,fd=myfd Note that numeric FDs cannot be referenced directly in HMP, only named FDs. And also CLI usage, by leak FD 3 from parent by clearing O_CLOEXEC, then spawning QEMU with -chardev socket,fd=3,id=mon -mon chardev=mon,mode=control Note that named FDs cannot be referenced in CLI args, only numeric FDs. We do not wire this up in the legacy chardev syntax, so you cannot use FD passing with '-qmp', you must use the modern '-mon' + '-chardev' pair. When passing pre-opened FDs there is a restriction on use of TLS encryption. It can be used on a server socket chardev, but cannot be used for a client socket chardev. This is because when validating a server's certificate, the client needs to have a hostname available to match against the certificate identity. An illustrative example of usage is: #!/usr/bin/perl use IO::Socket::UNIX; use Fcntl; unlink "/tmp/qmp"; my $srv = IO::Socket::UNIX->new( Type => SOCK_STREAM(), Local => "/tmp/qmp", Listen => 1, ); my $flags = fcntl $srv, F_GETFD, 0; fcntl $srv, F_SETFD, $flags & ~FD_CLOEXEC; my $fd = $srv->fileno(); exec "qemu-system-x86_64", \ "-chardev", "socket,fd=$fd,server,nowait,id=mon", \ "-mon", "chardev=mon,mode=control"; Reviewed-by: Eric Blake <eblake@redhat.com> Signed-off-by: Daniel P. Berrange <berrange@redhat.com>
2017-12-21 13:57:54 +01:00
"Exactly one of 'path', 'fd' or 'host' required");
return;
}
if (host && !port) {
error_setg(errp, "chardev: socket: no port given");
return;
}
backend->type = CHARDEV_BACKEND_KIND_SOCKET;
sock = backend->u.socket.data = g_new0(ChardevSocket, 1);
qemu_chr_parse_common(opts, qapi_ChardevSocket_base(sock));
sock->has_nodelay = qemu_opt_get(opts, "delay");
sock->nodelay = !qemu_opt_get_bool(opts, "delay", true);
/*
* We have different default to QMP for 'server', hence
* we can't just check for existence of 'server'
*/
sock->has_server = true;
sock->server = qemu_opt_get_bool(opts, "server", false);
sock->has_telnet = qemu_opt_get(opts, "telnet");
sock->telnet = qemu_opt_get_bool(opts, "telnet", false);
sock->has_tn3270 = qemu_opt_get(opts, "tn3270");
sock->tn3270 = qemu_opt_get_bool(opts, "tn3270", false);
sock->has_websocket = qemu_opt_get(opts, "websocket");
sock->websocket = qemu_opt_get_bool(opts, "websocket", false);
/*
* We have different default to QMP for 'wait' when 'server'
* is set, hence we can't just check for existence of 'wait'
*/
sock->has_wait = qemu_opt_find(opts, "wait") || sock->server;
sock->wait = qemu_opt_get_bool(opts, "wait", true);
sock->has_reconnect = qemu_opt_find(opts, "reconnect");
sock->reconnect = qemu_opt_get_number(opts, "reconnect", 0);
sock->has_tls_creds = qemu_opt_get(opts, "tls-creds");
sock->tls_creds = g_strdup(qemu_opt_get(opts, "tls-creds"));
sock->has_tls_authz = qemu_opt_get(opts, "tls-authz");
sock->tls_authz = g_strdup(qemu_opt_get(opts, "tls-authz"));
addr = g_new0(SocketAddressLegacy, 1);
if (path) {
UnixSocketAddress *q_unix;
addr->type = SOCKET_ADDRESS_LEGACY_KIND_UNIX;
q_unix = addr->u.q_unix.data = g_new0(UnixSocketAddress, 1);
q_unix->path = g_strdup(path);
} else if (host) {
addr->type = SOCKET_ADDRESS_LEGACY_KIND_INET;
addr->u.inet.data = g_new(InetSocketAddress, 1);
*addr->u.inet.data = (InetSocketAddress) {
.host = g_strdup(host),
.port = g_strdup(port),
.has_to = qemu_opt_get(opts, "to"),
.to = qemu_opt_get_number(opts, "to", 0),
.has_ipv4 = qemu_opt_get(opts, "ipv4"),
.ipv4 = qemu_opt_get_bool(opts, "ipv4", 0),
.has_ipv6 = qemu_opt_get(opts, "ipv6"),
.ipv6 = qemu_opt_get_bool(opts, "ipv6", 0),
};
char: allow passing pre-opened socket file descriptor at startup When starting QEMU management apps will usually setup a monitor socket, and then open it immediately after startup. If not using QEMU's own -daemonize arg, this process can be troublesome to handle correctly. The mgmt app will need to repeatedly call connect() until it succeeds, because it does not know when QEMU has created the listener socket. If can't retry connect() forever though, because an error might have caused QEMU to exit before it even creates the monitor. The obvious way to fix this kind of problem is to just pass in a pre-opened socket file descriptor for the QEMU monitor to listen on. The management app can now immediately call connect() just once. If connect() fails it knows that QEMU has exited with an error. The SocketAddress(Legacy) structs allow for FD passing via the monitor, and now via inherited file descriptors from the process that spawned QEMU. The final missing piece is adding a 'fd' parameter in the socket chardev options. This allows both HMP usage, pass any FD number with SCM_RIGHTS, then running HMP commands: getfd myfd chardev-add socket,fd=myfd Note that numeric FDs cannot be referenced directly in HMP, only named FDs. And also CLI usage, by leak FD 3 from parent by clearing O_CLOEXEC, then spawning QEMU with -chardev socket,fd=3,id=mon -mon chardev=mon,mode=control Note that named FDs cannot be referenced in CLI args, only numeric FDs. We do not wire this up in the legacy chardev syntax, so you cannot use FD passing with '-qmp', you must use the modern '-mon' + '-chardev' pair. When passing pre-opened FDs there is a restriction on use of TLS encryption. It can be used on a server socket chardev, but cannot be used for a client socket chardev. This is because when validating a server's certificate, the client needs to have a hostname available to match against the certificate identity. An illustrative example of usage is: #!/usr/bin/perl use IO::Socket::UNIX; use Fcntl; unlink "/tmp/qmp"; my $srv = IO::Socket::UNIX->new( Type => SOCK_STREAM(), Local => "/tmp/qmp", Listen => 1, ); my $flags = fcntl $srv, F_GETFD, 0; fcntl $srv, F_SETFD, $flags & ~FD_CLOEXEC; my $fd = $srv->fileno(); exec "qemu-system-x86_64", \ "-chardev", "socket,fd=$fd,server,nowait,id=mon", \ "-mon", "chardev=mon,mode=control"; Reviewed-by: Eric Blake <eblake@redhat.com> Signed-off-by: Daniel P. Berrange <berrange@redhat.com>
2017-12-21 13:57:54 +01:00
} else if (fd) {
addr->type = SOCKET_ADDRESS_LEGACY_KIND_FD;
addr->u.fd.data = g_new(String, 1);
addr->u.fd.data->str = g_strdup(fd);
} else {
g_assert_not_reached();
}
sock->addr = addr;
}
static void
char_socket_get_addr(Object *obj, Visitor *v, const char *name,
void *opaque, Error **errp)
{
SocketChardev *s = SOCKET_CHARDEV(obj);
visit_type_SocketAddress(v, name, &s->addr, errp);
}
static bool
char_socket_get_connected(Object *obj, Error **errp)
{
SocketChardev *s = SOCKET_CHARDEV(obj);
return s->state == TCP_CHARDEV_STATE_CONNECTED;
}
static void char_socket_class_init(ObjectClass *oc, void *data)
{
ChardevClass *cc = CHARDEV_CLASS(oc);
cc->parse = qemu_chr_parse_socket;
cc->open = qmp_chardev_open_socket;
cc->chr_wait_connected = tcp_chr_wait_connected;
cc->chr_write = tcp_chr_write;
cc->chr_sync_read = tcp_chr_sync_read;
cc->chr_disconnect = tcp_chr_disconnect;
cc->get_msgfds = tcp_get_msgfds;
cc->set_msgfds = tcp_set_msgfds;
cc->chr_add_client = tcp_chr_add_client;
cc->chr_add_watch = tcp_chr_add_watch;
cc->chr_update_read_handler = tcp_chr_update_read_handler;
object_class_property_add(oc, "addr", "SocketAddress",
char_socket_get_addr, NULL,
NULL, NULL, &error_abort);
object_class_property_add_bool(oc, "connected", char_socket_get_connected,
NULL, &error_abort);
}
static const TypeInfo char_socket_type_info = {
.name = TYPE_CHARDEV_SOCKET,
.parent = TYPE_CHARDEV,
.instance_size = sizeof(SocketChardev),
.instance_finalize = char_socket_finalize,
.class_init = char_socket_class_init,
};
static void register_types(void)
{
type_register_static(&char_socket_type_info);
}
type_init(register_types);