qemu-e2k/util/qemu-sockets.c
Knut Omang 9cf961bba7 sockets: Handle race condition between binds to the same port
If an offset of ports is specified to the inet_listen_saddr function(),
and two or more processes tries to bind from these ports at the same time,
occasionally more than one process may be able to bind to the same
port. The condition is detected by listen() but too late to avoid a failure.

This function is called by socket_listen() and used
by all socket listening code in QEMU, so all cases where any form of dynamic
port selection is used should be subject to this issue.

Add code to close and re-establish the socket when this
condition is observed, hiding the race condition from the user.

Also clean up some issues with error handling to allow more
accurate reporting of the cause of an error.

This has been developed and tested by means of the
test-listen unit test in the previous commit.
Enable the test for make check now that it passes.

Reviewed-by: Bhavesh Davda <bhavesh.davda@oracle.com>
Reviewed-by: Yuval Shaia <yuval.shaia@oracle.com>
Reviewed-by: Girish Moodalbail <girish.moodalbail@oracle.com>
Signed-off-by: Knut Omang <knut.omang@oracle.com>
Reviewed-by: Daniel P. Berrange <berrange@redhat.com>
Signed-off-by: Daniel P. Berrange <berrange@redhat.com>
2017-10-16 16:55:31 +01:00

1281 lines
33 KiB
C

/*
* inet and unix socket functions for qemu
*
* (c) 2008 Gerd Hoffmann <kraxel@redhat.com>
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License as published by
* the Free Software Foundation; under version 2 of the License.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*
* Contributions after 2012-01-13 are licensed under the terms of the
* GNU GPL, version 2 or (at your option) any later version.
*/
#include "qemu/osdep.h"
#ifdef CONFIG_AF_VSOCK
#include <linux/vm_sockets.h>
#endif /* CONFIG_AF_VSOCK */
#include "monitor/monitor.h"
#include "qapi/clone-visitor.h"
#include "qapi/error.h"
#include "qemu/sockets.h"
#include "qemu/main-loop.h"
#include "qapi/clone-visitor.h"
#include "qapi/qobject-input-visitor.h"
#include "qapi/qobject-output-visitor.h"
#include "qapi-visit.h"
#include "qemu/cutils.h"
#ifndef AI_ADDRCONFIG
# define AI_ADDRCONFIG 0
#endif
#ifndef AI_V4MAPPED
# define AI_V4MAPPED 0
#endif
#ifndef AI_NUMERICSERV
# define AI_NUMERICSERV 0
#endif
static int inet_getport(struct addrinfo *e)
{
struct sockaddr_in *i4;
struct sockaddr_in6 *i6;
switch (e->ai_family) {
case PF_INET6:
i6 = (void*)e->ai_addr;
return ntohs(i6->sin6_port);
case PF_INET:
i4 = (void*)e->ai_addr;
return ntohs(i4->sin_port);
default:
return 0;
}
}
static void inet_setport(struct addrinfo *e, int port)
{
struct sockaddr_in *i4;
struct sockaddr_in6 *i6;
switch (e->ai_family) {
case PF_INET6:
i6 = (void*)e->ai_addr;
i6->sin6_port = htons(port);
break;
case PF_INET:
i4 = (void*)e->ai_addr;
i4->sin_port = htons(port);
break;
}
}
NetworkAddressFamily inet_netfamily(int family)
{
switch (family) {
case PF_INET6: return NETWORK_ADDRESS_FAMILY_IPV6;
case PF_INET: return NETWORK_ADDRESS_FAMILY_IPV4;
case PF_UNIX: return NETWORK_ADDRESS_FAMILY_UNIX;
#ifdef CONFIG_AF_VSOCK
case PF_VSOCK: return NETWORK_ADDRESS_FAMILY_VSOCK;
#endif /* CONFIG_AF_VSOCK */
}
return NETWORK_ADDRESS_FAMILY_UNKNOWN;
}
/*
* Matrix we're trying to apply
*
* ipv4 ipv6 family
* - - PF_UNSPEC
* - f PF_INET
* - t PF_INET6
* f - PF_INET6
* f f <error>
* f t PF_INET6
* t - PF_INET
* t f PF_INET
* t t PF_INET6/PF_UNSPEC
*
* NB, this matrix is only about getting the necessary results
* from getaddrinfo(). Some of the cases require further work
* after reading results from getaddrinfo in order to fully
* apply the logic the end user wants.
*
* In the first and last cases, we must set IPV6_V6ONLY=0
* when binding, to allow a single listener to potentially
* accept both IPv4+6 addresses.
*/
int inet_ai_family_from_address(InetSocketAddress *addr,
Error **errp)
{
if (addr->has_ipv6 && addr->has_ipv4 &&
!addr->ipv6 && !addr->ipv4) {
error_setg(errp, "Cannot disable IPv4 and IPv6 at same time");
return PF_UNSPEC;
}
if ((addr->has_ipv6 && addr->ipv6) && (addr->has_ipv4 && addr->ipv4)) {
/*
* Some backends can only do a single listener. In that case
* we want empty hostname to resolve to "::" and then use the
* flag IPV6_V6ONLY==0 to get both protocols on 1 socket. This
* doesn't work for addresses other than "", so they're just
* inevitably broken until multiple listeners can be used,
* and thus we honour getaddrinfo automatic protocol detection
* Once all backends do multi-listener, remove the PF_INET6
* branch entirely.
*/
if (!addr->host || g_str_equal(addr->host, "")) {
return PF_INET6;
} else {
return PF_UNSPEC;
}
}
if ((addr->has_ipv6 && addr->ipv6) || (addr->has_ipv4 && !addr->ipv4)) {
return PF_INET6;
}
if ((addr->has_ipv4 && addr->ipv4) || (addr->has_ipv6 && !addr->ipv6)) {
return PF_INET;
}
return PF_UNSPEC;
}
static int create_fast_reuse_socket(struct addrinfo *e)
{
int slisten = qemu_socket(e->ai_family, e->ai_socktype, e->ai_protocol);
if (slisten < 0) {
return -1;
}
socket_set_fast_reuse(slisten);
return slisten;
}
static int try_bind(int socket, InetSocketAddress *saddr, struct addrinfo *e)
{
#ifndef IPV6_V6ONLY
return bind(socket, e->ai_addr, e->ai_addrlen);
#else
/*
* Deals with first & last cases in matrix in comment
* for inet_ai_family_from_address().
*/
int v6only =
((!saddr->has_ipv4 && !saddr->has_ipv6) ||
(saddr->has_ipv4 && saddr->ipv4 &&
saddr->has_ipv6 && saddr->ipv6)) ? 0 : 1;
int stat;
rebind:
if (e->ai_family == PF_INET6) {
qemu_setsockopt(socket, IPPROTO_IPV6, IPV6_V6ONLY, &v6only,
sizeof(v6only));
}
stat = bind(socket, e->ai_addr, e->ai_addrlen);
if (!stat) {
return 0;
}
/* If we got EADDRINUSE from an IPv6 bind & v6only is unset,
* it could be that the IPv4 port is already claimed, so retry
* with v6only set
*/
if (e->ai_family == PF_INET6 && errno == EADDRINUSE && !v6only) {
v6only = 1;
goto rebind;
}
return stat;
#endif
}
static int inet_listen_saddr(InetSocketAddress *saddr,
int port_offset,
bool update_addr,
Error **errp)
{
struct addrinfo ai,*res,*e;
char port[33];
char uaddr[INET6_ADDRSTRLEN+1];
char uport[33];
int rc, port_min, port_max, p;
int slisten = 0;
int saved_errno = 0;
bool socket_created = false;
Error *err = NULL;
memset(&ai,0, sizeof(ai));
ai.ai_flags = AI_PASSIVE;
if (saddr->has_numeric && saddr->numeric) {
ai.ai_flags |= AI_NUMERICHOST | AI_NUMERICSERV;
}
ai.ai_family = inet_ai_family_from_address(saddr, &err);
ai.ai_socktype = SOCK_STREAM;
if (err) {
error_propagate(errp, err);
return -1;
}
if (saddr->host == NULL) {
error_setg(errp, "host not specified");
return -1;
}
if (saddr->port != NULL) {
pstrcpy(port, sizeof(port), saddr->port);
} else {
port[0] = '\0';
}
/* lookup */
if (port_offset) {
unsigned long long baseport;
if (strlen(port) == 0) {
error_setg(errp, "port not specified");
return -1;
}
if (parse_uint_full(port, &baseport, 10) < 0) {
error_setg(errp, "can't convert to a number: %s", port);
return -1;
}
if (baseport > 65535 ||
baseport + port_offset > 65535) {
error_setg(errp, "port %s out of range", port);
return -1;
}
snprintf(port, sizeof(port), "%d", (int)baseport + port_offset);
}
rc = getaddrinfo(strlen(saddr->host) ? saddr->host : NULL,
strlen(port) ? port : NULL, &ai, &res);
if (rc != 0) {
error_setg(errp, "address resolution failed for %s:%s: %s",
saddr->host, port, gai_strerror(rc));
return -1;
}
/* create socket + bind/listen */
for (e = res; e != NULL; e = e->ai_next) {
getnameinfo((struct sockaddr*)e->ai_addr,e->ai_addrlen,
uaddr,INET6_ADDRSTRLEN,uport,32,
NI_NUMERICHOST | NI_NUMERICSERV);
slisten = create_fast_reuse_socket(e);
if (slisten < 0) {
continue;
}
socket_created = true;
port_min = inet_getport(e);
port_max = saddr->has_to ? saddr->to + port_offset : port_min;
for (p = port_min; p <= port_max; p++) {
inet_setport(e, p);
rc = try_bind(slisten, saddr, e);
if (rc) {
if (errno == EADDRINUSE) {
continue;
} else {
error_setg_errno(errp, errno, "Failed to bind socket");
goto listen_failed;
}
}
if (!listen(slisten, 1)) {
goto listen_ok;
}
if (errno != EADDRINUSE) {
error_setg_errno(errp, errno, "Failed to listen on socket");
goto listen_failed;
}
/* Someone else managed to bind to the same port and beat us
* to listen on it! Socket semantics does not allow us to
* recover from this situation, so we need to recreate the
* socket to allow bind attempts for subsequent ports:
*/
closesocket(slisten);
slisten = create_fast_reuse_socket(e);
if (slisten < 0) {
error_setg_errno(errp, errno,
"Failed to recreate failed listening socket");
goto listen_failed;
}
}
}
error_setg_errno(errp, errno,
socket_created ?
"Failed to find an available port" :
"Failed to create a socket");
listen_failed:
saved_errno = errno;
if (slisten >= 0) {
closesocket(slisten);
}
freeaddrinfo(res);
errno = saved_errno;
return -1;
listen_ok:
if (update_addr) {
g_free(saddr->host);
saddr->host = g_strdup(uaddr);
g_free(saddr->port);
saddr->port = g_strdup_printf("%d",
inet_getport(e) - port_offset);
saddr->has_ipv6 = saddr->ipv6 = e->ai_family == PF_INET6;
saddr->has_ipv4 = saddr->ipv4 = e->ai_family != PF_INET6;
}
freeaddrinfo(res);
return slisten;
}
#ifdef _WIN32
#define QEMU_SOCKET_RC_INPROGRESS(rc) \
((rc) == -EINPROGRESS || (rc) == -EWOULDBLOCK || (rc) == -WSAEALREADY)
#else
#define QEMU_SOCKET_RC_INPROGRESS(rc) \
((rc) == -EINPROGRESS)
#endif
static int inet_connect_addr(struct addrinfo *addr, Error **errp);
static int inet_connect_addr(struct addrinfo *addr, Error **errp)
{
int sock, rc;
sock = qemu_socket(addr->ai_family, addr->ai_socktype, addr->ai_protocol);
if (sock < 0) {
error_setg_errno(errp, errno, "Failed to create socket");
return -1;
}
socket_set_fast_reuse(sock);
/* connect to peer */
do {
rc = 0;
if (connect(sock, addr->ai_addr, addr->ai_addrlen) < 0) {
rc = -errno;
}
} while (rc == -EINTR);
if (rc < 0) {
error_setg_errno(errp, errno, "Failed to connect socket");
closesocket(sock);
return -1;
}
return sock;
}
static struct addrinfo *inet_parse_connect_saddr(InetSocketAddress *saddr,
Error **errp)
{
struct addrinfo ai, *res;
int rc;
Error *err = NULL;
static int useV4Mapped = 1;
memset(&ai, 0, sizeof(ai));
ai.ai_flags = AI_CANONNAME | AI_ADDRCONFIG;
if (atomic_read(&useV4Mapped)) {
ai.ai_flags |= AI_V4MAPPED;
}
ai.ai_family = inet_ai_family_from_address(saddr, &err);
ai.ai_socktype = SOCK_STREAM;
if (err) {
error_propagate(errp, err);
return NULL;
}
if (saddr->host == NULL || saddr->port == NULL) {
error_setg(errp, "host and/or port not specified");
return NULL;
}
/* lookup */
rc = getaddrinfo(saddr->host, saddr->port, &ai, &res);
/* At least FreeBSD and OS-X 10.6 declare AI_V4MAPPED but
* then don't implement it in their getaddrinfo(). Detect
* this and retry without the flag since that's preferrable
* to a fatal error
*/
if (rc == EAI_BADFLAGS &&
(ai.ai_flags & AI_V4MAPPED)) {
atomic_set(&useV4Mapped, 0);
ai.ai_flags &= ~AI_V4MAPPED;
rc = getaddrinfo(saddr->host, saddr->port, &ai, &res);
}
if (rc != 0) {
error_setg(errp, "address resolution failed for %s:%s: %s",
saddr->host, saddr->port, gai_strerror(rc));
return NULL;
}
return res;
}
/**
* Create a socket and connect it to an address.
*
* @saddr: Inet socket address specification
* @errp: set on error
*
* Returns: -1 on error, file descriptor on success.
*/
int inet_connect_saddr(InetSocketAddress *saddr, Error **errp)
{
Error *local_err = NULL;
struct addrinfo *res, *e;
int sock = -1;
res = inet_parse_connect_saddr(saddr, errp);
if (!res) {
return -1;
}
for (e = res; e != NULL; e = e->ai_next) {
error_free(local_err);
local_err = NULL;
sock = inet_connect_addr(e, &local_err);
if (sock >= 0) {
break;
}
}
if (sock < 0) {
error_propagate(errp, local_err);
}
freeaddrinfo(res);
return sock;
}
static int inet_dgram_saddr(InetSocketAddress *sraddr,
InetSocketAddress *sladdr,
Error **errp)
{
struct addrinfo ai, *peer = NULL, *local = NULL;
const char *addr;
const char *port;
int sock = -1, rc;
Error *err = NULL;
/* lookup peer addr */
memset(&ai,0, sizeof(ai));
ai.ai_flags = AI_CANONNAME | AI_V4MAPPED | AI_ADDRCONFIG;
ai.ai_family = inet_ai_family_from_address(sraddr, &err);
ai.ai_socktype = SOCK_DGRAM;
if (err) {
error_propagate(errp, err);
goto err;
}
addr = sraddr->host;
port = sraddr->port;
if (addr == NULL || strlen(addr) == 0) {
addr = "localhost";
}
if (port == NULL || strlen(port) == 0) {
error_setg(errp, "remote port not specified");
goto err;
}
if ((rc = getaddrinfo(addr, port, &ai, &peer)) != 0) {
error_setg(errp, "address resolution failed for %s:%s: %s", addr, port,
gai_strerror(rc));
goto err;
}
/* lookup local addr */
memset(&ai,0, sizeof(ai));
ai.ai_flags = AI_PASSIVE;
ai.ai_family = peer->ai_family;
ai.ai_socktype = SOCK_DGRAM;
if (sladdr) {
addr = sladdr->host;
port = sladdr->port;
if (addr == NULL || strlen(addr) == 0) {
addr = NULL;
}
if (!port || strlen(port) == 0) {
port = "0";
}
} else {
addr = NULL;
port = "0";
}
if ((rc = getaddrinfo(addr, port, &ai, &local)) != 0) {
error_setg(errp, "address resolution failed for %s:%s: %s", addr, port,
gai_strerror(rc));
goto err;
}
/* create socket */
sock = qemu_socket(peer->ai_family, peer->ai_socktype, peer->ai_protocol);
if (sock < 0) {
error_setg_errno(errp, errno, "Failed to create socket");
goto err;
}
socket_set_fast_reuse(sock);
/* bind socket */
if (bind(sock, local->ai_addr, local->ai_addrlen) < 0) {
error_setg_errno(errp, errno, "Failed to bind socket");
goto err;
}
/* connect to peer */
if (connect(sock,peer->ai_addr,peer->ai_addrlen) < 0) {
error_setg_errno(errp, errno, "Failed to connect socket");
goto err;
}
freeaddrinfo(local);
freeaddrinfo(peer);
return sock;
err:
if (sock != -1) {
closesocket(sock);
}
if (local) {
freeaddrinfo(local);
}
if (peer) {
freeaddrinfo(peer);
}
return -1;
}
/* compatibility wrapper */
int inet_parse(InetSocketAddress *addr, const char *str, Error **errp)
{
const char *optstr, *h;
char host[65];
char port[33];
int to;
int pos;
memset(addr, 0, sizeof(*addr));
/* parse address */
if (str[0] == ':') {
/* no host given */
host[0] = '\0';
if (sscanf(str, ":%32[^,]%n", port, &pos) != 1) {
error_setg(errp, "error parsing port in address '%s'", str);
return -1;
}
} else if (str[0] == '[') {
/* IPv6 addr */
if (sscanf(str, "[%64[^]]]:%32[^,]%n", host, port, &pos) != 2) {
error_setg(errp, "error parsing IPv6 address '%s'", str);
return -1;
}
} else {
/* hostname or IPv4 addr */
if (sscanf(str, "%64[^:]:%32[^,]%n", host, port, &pos) != 2) {
error_setg(errp, "error parsing address '%s'", str);
return -1;
}
}
addr->host = g_strdup(host);
addr->port = g_strdup(port);
/* parse options */
optstr = str + pos;
h = strstr(optstr, ",to=");
if (h) {
h += 4;
if (sscanf(h, "%d%n", &to, &pos) != 1 ||
(h[pos] != '\0' && h[pos] != ',')) {
error_setg(errp, "error parsing to= argument");
return -1;
}
addr->has_to = true;
addr->to = to;
}
if (strstr(optstr, ",ipv4")) {
addr->ipv4 = addr->has_ipv4 = true;
}
if (strstr(optstr, ",ipv6")) {
addr->ipv6 = addr->has_ipv6 = true;
}
return 0;
}
/**
* Create a blocking socket and connect it to an address.
*
* @str: address string
* @errp: set in case of an error
*
* Returns -1 in case of error, file descriptor on success
**/
int inet_connect(const char *str, Error **errp)
{
int sock = -1;
InetSocketAddress *addr = g_new(InetSocketAddress, 1);
if (!inet_parse(addr, str, errp)) {
sock = inet_connect_saddr(addr, errp);
}
qapi_free_InetSocketAddress(addr);
return sock;
}
#ifdef CONFIG_AF_VSOCK
static bool vsock_parse_vaddr_to_sockaddr(const VsockSocketAddress *vaddr,
struct sockaddr_vm *svm,
Error **errp)
{
unsigned long long val;
memset(svm, 0, sizeof(*svm));
svm->svm_family = AF_VSOCK;
if (parse_uint_full(vaddr->cid, &val, 10) < 0 ||
val > UINT32_MAX) {
error_setg(errp, "Failed to parse cid '%s'", vaddr->cid);
return false;
}
svm->svm_cid = val;
if (parse_uint_full(vaddr->port, &val, 10) < 0 ||
val > UINT32_MAX) {
error_setg(errp, "Failed to parse port '%s'", vaddr->port);
return false;
}
svm->svm_port = val;
return true;
}
static int vsock_connect_addr(const struct sockaddr_vm *svm, Error **errp)
{
int sock, rc;
sock = qemu_socket(AF_VSOCK, SOCK_STREAM, 0);
if (sock < 0) {
error_setg_errno(errp, errno, "Failed to create socket");
return -1;
}
/* connect to peer */
do {
rc = 0;
if (connect(sock, (const struct sockaddr *)svm, sizeof(*svm)) < 0) {
rc = -errno;
}
} while (rc == -EINTR);
if (rc < 0) {
error_setg_errno(errp, errno, "Failed to connect socket");
closesocket(sock);
return -1;
}
return sock;
}
static int vsock_connect_saddr(VsockSocketAddress *vaddr, Error **errp)
{
struct sockaddr_vm svm;
int sock = -1;
if (!vsock_parse_vaddr_to_sockaddr(vaddr, &svm, errp)) {
return -1;
}
sock = vsock_connect_addr(&svm, errp);
return sock;
}
static int vsock_listen_saddr(VsockSocketAddress *vaddr,
Error **errp)
{
struct sockaddr_vm svm;
int slisten;
if (!vsock_parse_vaddr_to_sockaddr(vaddr, &svm, errp)) {
return -1;
}
slisten = qemu_socket(AF_VSOCK, SOCK_STREAM, 0);
if (slisten < 0) {
error_setg_errno(errp, errno, "Failed to create socket");
return -1;
}
if (bind(slisten, (const struct sockaddr *)&svm, sizeof(svm)) != 0) {
error_setg_errno(errp, errno, "Failed to bind socket");
closesocket(slisten);
return -1;
}
if (listen(slisten, 1) != 0) {
error_setg_errno(errp, errno, "Failed to listen on socket");
closesocket(slisten);
return -1;
}
return slisten;
}
static int vsock_parse(VsockSocketAddress *addr, const char *str,
Error **errp)
{
char cid[33];
char port[33];
int n;
if (sscanf(str, "%32[^:]:%32[^,]%n", cid, port, &n) != 2) {
error_setg(errp, "error parsing address '%s'", str);
return -1;
}
if (str[n] != '\0') {
error_setg(errp, "trailing characters in address '%s'", str);
return -1;
}
addr->cid = g_strdup(cid);
addr->port = g_strdup(port);
return 0;
}
#else
static void vsock_unsupported(Error **errp)
{
error_setg(errp, "socket family AF_VSOCK unsupported");
}
static int vsock_connect_saddr(VsockSocketAddress *vaddr, Error **errp)
{
vsock_unsupported(errp);
return -1;
}
static int vsock_listen_saddr(VsockSocketAddress *vaddr,
Error **errp)
{
vsock_unsupported(errp);
return -1;
}
static int vsock_parse(VsockSocketAddress *addr, const char *str,
Error **errp)
{
vsock_unsupported(errp);
return -1;
}
#endif /* CONFIG_AF_VSOCK */
#ifndef _WIN32
static int unix_listen_saddr(UnixSocketAddress *saddr,
bool update_addr,
Error **errp)
{
struct sockaddr_un un;
int sock, fd;
char *pathbuf = NULL;
const char *path;
sock = qemu_socket(PF_UNIX, SOCK_STREAM, 0);
if (sock < 0) {
error_setg_errno(errp, errno, "Failed to create Unix socket");
return -1;
}
if (saddr->path && saddr->path[0]) {
path = saddr->path;
} else {
const char *tmpdir = getenv("TMPDIR");
tmpdir = tmpdir ? tmpdir : "/tmp";
path = pathbuf = g_strdup_printf("%s/qemu-socket-XXXXXX", tmpdir);
}
if (strlen(path) > sizeof(un.sun_path)) {
error_setg(errp, "UNIX socket path '%s' is too long", path);
error_append_hint(errp, "Path must be less than %zu bytes\n",
sizeof(un.sun_path));
goto err;
}
if (pathbuf != NULL) {
/*
* This dummy fd usage silences the mktemp() unsecure warning.
* Using mkstemp() doesn't make things more secure here
* though. bind() complains about existing files, so we have
* to unlink first and thus re-open the race window. The
* worst case possible is bind() failing, i.e. a DoS attack.
*/
fd = mkstemp(pathbuf);
if (fd < 0) {
error_setg_errno(errp, errno,
"Failed to make a temporary socket %s", pathbuf);
goto err;
}
close(fd);
}
if (unlink(path) < 0 && errno != ENOENT) {
error_setg_errno(errp, errno,
"Failed to unlink socket %s", path);
goto err;
}
memset(&un, 0, sizeof(un));
un.sun_family = AF_UNIX;
strncpy(un.sun_path, path, sizeof(un.sun_path));
if (bind(sock, (struct sockaddr*) &un, sizeof(un)) < 0) {
error_setg_errno(errp, errno, "Failed to bind socket to %s", path);
goto err;
}
if (listen(sock, 1) < 0) {
error_setg_errno(errp, errno, "Failed to listen on socket");
goto err;
}
if (update_addr && pathbuf) {
g_free(saddr->path);
saddr->path = pathbuf;
} else {
g_free(pathbuf);
}
return sock;
err:
g_free(pathbuf);
closesocket(sock);
return -1;
}
static int unix_connect_saddr(UnixSocketAddress *saddr, Error **errp)
{
struct sockaddr_un un;
int sock, rc;
if (saddr->path == NULL) {
error_setg(errp, "unix connect: no path specified");
return -1;
}
sock = qemu_socket(PF_UNIX, SOCK_STREAM, 0);
if (sock < 0) {
error_setg_errno(errp, errno, "Failed to create socket");
return -1;
}
if (strlen(saddr->path) > sizeof(un.sun_path)) {
error_setg(errp, "UNIX socket path '%s' is too long", saddr->path);
error_append_hint(errp, "Path must be less than %zu bytes\n",
sizeof(un.sun_path));
goto err;
}
memset(&un, 0, sizeof(un));
un.sun_family = AF_UNIX;
strncpy(un.sun_path, saddr->path, sizeof(un.sun_path));
/* connect to peer */
do {
rc = 0;
if (connect(sock, (struct sockaddr *) &un, sizeof(un)) < 0) {
rc = -errno;
}
} while (rc == -EINTR);
if (rc < 0) {
error_setg_errno(errp, -rc, "Failed to connect socket %s",
saddr->path);
goto err;
}
return sock;
err:
close(sock);
return -1;
}
#else
static int unix_listen_saddr(UnixSocketAddress *saddr,
bool update_addr,
Error **errp)
{
error_setg(errp, "unix sockets are not available on windows");
errno = ENOTSUP;
return -1;
}
static int unix_connect_saddr(UnixSocketAddress *saddr, Error **errp)
{
error_setg(errp, "unix sockets are not available on windows");
errno = ENOTSUP;
return -1;
}
#endif
/* compatibility wrapper */
int unix_listen(const char *str, char *ostr, int olen, Error **errp)
{
char *path, *optstr;
int sock, len;
UnixSocketAddress *saddr;
saddr = g_new0(UnixSocketAddress, 1);
optstr = strchr(str, ',');
if (optstr) {
len = optstr - str;
if (len) {
path = g_malloc(len+1);
snprintf(path, len+1, "%.*s", len, str);
saddr->path = path;
}
} else {
saddr->path = g_strdup(str);
}
sock = unix_listen_saddr(saddr, true, errp);
if (sock != -1 && ostr) {
snprintf(ostr, olen, "%s%s", saddr->path, optstr ? optstr : "");
}
qapi_free_UnixSocketAddress(saddr);
return sock;
}
int unix_connect(const char *path, Error **errp)
{
UnixSocketAddress *saddr;
int sock;
saddr = g_new0(UnixSocketAddress, 1);
saddr->path = g_strdup(path);
sock = unix_connect_saddr(saddr, errp);
qapi_free_UnixSocketAddress(saddr);
return sock;
}
SocketAddress *socket_parse(const char *str, Error **errp)
{
SocketAddress *addr;
addr = g_new0(SocketAddress, 1);
if (strstart(str, "unix:", NULL)) {
if (str[5] == '\0') {
error_setg(errp, "invalid Unix socket address");
goto fail;
} else {
addr->type = SOCKET_ADDRESS_TYPE_UNIX;
addr->u.q_unix.path = g_strdup(str + 5);
}
} else if (strstart(str, "fd:", NULL)) {
if (str[3] == '\0') {
error_setg(errp, "invalid file descriptor address");
goto fail;
} else {
addr->type = SOCKET_ADDRESS_TYPE_FD;
addr->u.fd.str = g_strdup(str + 3);
}
} else if (strstart(str, "vsock:", NULL)) {
addr->type = SOCKET_ADDRESS_TYPE_VSOCK;
if (vsock_parse(&addr->u.vsock, str + strlen("vsock:"), errp)) {
goto fail;
}
} else {
addr->type = SOCKET_ADDRESS_TYPE_INET;
if (inet_parse(&addr->u.inet, str, errp)) {
goto fail;
}
}
return addr;
fail:
qapi_free_SocketAddress(addr);
return NULL;
}
int socket_connect(SocketAddress *addr, Error **errp)
{
int fd;
switch (addr->type) {
case SOCKET_ADDRESS_TYPE_INET:
fd = inet_connect_saddr(&addr->u.inet, errp);
break;
case SOCKET_ADDRESS_TYPE_UNIX:
fd = unix_connect_saddr(&addr->u.q_unix, errp);
break;
case SOCKET_ADDRESS_TYPE_FD:
fd = monitor_get_fd(cur_mon, addr->u.fd.str, errp);
break;
case SOCKET_ADDRESS_TYPE_VSOCK:
fd = vsock_connect_saddr(&addr->u.vsock, errp);
break;
default:
abort();
}
return fd;
}
int socket_listen(SocketAddress *addr, Error **errp)
{
int fd;
switch (addr->type) {
case SOCKET_ADDRESS_TYPE_INET:
fd = inet_listen_saddr(&addr->u.inet, 0, false, errp);
break;
case SOCKET_ADDRESS_TYPE_UNIX:
fd = unix_listen_saddr(&addr->u.q_unix, false, errp);
break;
case SOCKET_ADDRESS_TYPE_FD:
fd = monitor_get_fd(cur_mon, addr->u.fd.str, errp);
break;
case SOCKET_ADDRESS_TYPE_VSOCK:
fd = vsock_listen_saddr(&addr->u.vsock, errp);
break;
default:
abort();
}
return fd;
}
void socket_listen_cleanup(int fd, Error **errp)
{
SocketAddress *addr;
addr = socket_local_address(fd, errp);
if (addr->type == SOCKET_ADDRESS_TYPE_UNIX
&& addr->u.q_unix.path) {
if (unlink(addr->u.q_unix.path) < 0 && errno != ENOENT) {
error_setg_errno(errp, errno,
"Failed to unlink socket %s",
addr->u.q_unix.path);
}
}
qapi_free_SocketAddress(addr);
}
int socket_dgram(SocketAddress *remote, SocketAddress *local, Error **errp)
{
int fd;
/*
* TODO SOCKET_ADDRESS_TYPE_FD when fd is AF_INET or AF_INET6
* (although other address families can do SOCK_DGRAM, too)
*/
switch (remote->type) {
case SOCKET_ADDRESS_TYPE_INET:
fd = inet_dgram_saddr(&remote->u.inet,
local ? &local->u.inet : NULL, errp);
break;
default:
error_setg(errp, "socket type unsupported for datagram");
fd = -1;
}
return fd;
}
static SocketAddress *
socket_sockaddr_to_address_inet(struct sockaddr_storage *sa,
socklen_t salen,
Error **errp)
{
char host[NI_MAXHOST];
char serv[NI_MAXSERV];
SocketAddress *addr;
InetSocketAddress *inet;
int ret;
ret = getnameinfo((struct sockaddr *)sa, salen,
host, sizeof(host),
serv, sizeof(serv),
NI_NUMERICHOST | NI_NUMERICSERV);
if (ret != 0) {
error_setg(errp, "Cannot format numeric socket address: %s",
gai_strerror(ret));
return NULL;
}
addr = g_new0(SocketAddress, 1);
addr->type = SOCKET_ADDRESS_TYPE_INET;
inet = &addr->u.inet;
inet->host = g_strdup(host);
inet->port = g_strdup(serv);
if (sa->ss_family == AF_INET) {
inet->has_ipv4 = inet->ipv4 = true;
} else {
inet->has_ipv6 = inet->ipv6 = true;
}
return addr;
}
#ifndef WIN32
static SocketAddress *
socket_sockaddr_to_address_unix(struct sockaddr_storage *sa,
socklen_t salen,
Error **errp)
{
SocketAddress *addr;
struct sockaddr_un *su = (struct sockaddr_un *)sa;
addr = g_new0(SocketAddress, 1);
addr->type = SOCKET_ADDRESS_TYPE_UNIX;
if (su->sun_path[0]) {
addr->u.q_unix.path = g_strndup(su->sun_path, sizeof(su->sun_path));
}
return addr;
}
#endif /* WIN32 */
#ifdef CONFIG_AF_VSOCK
static SocketAddress *
socket_sockaddr_to_address_vsock(struct sockaddr_storage *sa,
socklen_t salen,
Error **errp)
{
SocketAddress *addr;
VsockSocketAddress *vaddr;
struct sockaddr_vm *svm = (struct sockaddr_vm *)sa;
addr = g_new0(SocketAddress, 1);
addr->type = SOCKET_ADDRESS_TYPE_VSOCK;
vaddr = &addr->u.vsock;
vaddr->cid = g_strdup_printf("%u", svm->svm_cid);
vaddr->port = g_strdup_printf("%u", svm->svm_port);
return addr;
}
#endif /* CONFIG_AF_VSOCK */
SocketAddress *
socket_sockaddr_to_address(struct sockaddr_storage *sa,
socklen_t salen,
Error **errp)
{
switch (sa->ss_family) {
case AF_INET:
case AF_INET6:
return socket_sockaddr_to_address_inet(sa, salen, errp);
#ifndef WIN32
case AF_UNIX:
return socket_sockaddr_to_address_unix(sa, salen, errp);
#endif /* WIN32 */
#ifdef CONFIG_AF_VSOCK
case AF_VSOCK:
return socket_sockaddr_to_address_vsock(sa, salen, errp);
#endif
default:
error_setg(errp, "socket family %d unsupported",
sa->ss_family);
return NULL;
}
return 0;
}
SocketAddress *socket_local_address(int fd, Error **errp)
{
struct sockaddr_storage ss;
socklen_t sslen = sizeof(ss);
if (getsockname(fd, (struct sockaddr *)&ss, &sslen) < 0) {
error_setg_errno(errp, errno, "%s",
"Unable to query local socket address");
return NULL;
}
return socket_sockaddr_to_address(&ss, sslen, errp);
}
SocketAddress *socket_remote_address(int fd, Error **errp)
{
struct sockaddr_storage ss;
socklen_t sslen = sizeof(ss);
if (getpeername(fd, (struct sockaddr *)&ss, &sslen) < 0) {
error_setg_errno(errp, errno, "%s",
"Unable to query remote socket address");
return NULL;
}
return socket_sockaddr_to_address(&ss, sslen, errp);
}
SocketAddress *socket_address_flatten(SocketAddressLegacy *addr_legacy)
{
SocketAddress *addr;
if (!addr_legacy) {
return NULL;
}
addr = g_new(SocketAddress, 1);
switch (addr_legacy->type) {
case SOCKET_ADDRESS_LEGACY_KIND_INET:
addr->type = SOCKET_ADDRESS_TYPE_INET;
QAPI_CLONE_MEMBERS(InetSocketAddress, &addr->u.inet,
addr_legacy->u.inet.data);
break;
case SOCKET_ADDRESS_LEGACY_KIND_UNIX:
addr->type = SOCKET_ADDRESS_TYPE_UNIX;
QAPI_CLONE_MEMBERS(UnixSocketAddress, &addr->u.q_unix,
addr_legacy->u.q_unix.data);
break;
case SOCKET_ADDRESS_LEGACY_KIND_VSOCK:
addr->type = SOCKET_ADDRESS_TYPE_VSOCK;
QAPI_CLONE_MEMBERS(VsockSocketAddress, &addr->u.vsock,
addr_legacy->u.vsock.data);
break;
case SOCKET_ADDRESS_LEGACY_KIND_FD:
addr->type = SOCKET_ADDRESS_TYPE_FD;
QAPI_CLONE_MEMBERS(String, &addr->u.fd, addr_legacy->u.fd.data);
break;
default:
abort();
}
return addr;
}