qemu/net/slirp.c
Jason Wang bc38e31b4e net: check the existence of peer before trying to pad
There could be case that peer is NULL. This can happen when during
network device hot-add where net device needs to be added first. So
the patch check the existence of peer before trying to do the pad.

Fixes: 969e50b61a ("net: Pad short frames to minimum size before sending from SLiRP/TAP")
Signed-off-by: Jason Wang <jasowang@redhat.com>
Reviewed-by: Bin Meng <bmeng.cn@gmail.com>
Reviewed-by: Stefan Weil <sw@weilnetz.de>
Message-id: 20210423031803.1479-1-jasowang@redhat.com
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
2021-04-23 11:11:28 +01:00

1125 lines
31 KiB
C

/*
* QEMU System Emulator
*
* Copyright (c) 2003-2008 Fabrice Bellard
*
* Permission is hereby granted, free of charge, to any person obtaining a copy
* of this software and associated documentation files (the "Software"), to deal
* in the Software without restriction, including without limitation the rights
* to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
* copies of the Software, and to permit persons to whom the Software is
* furnished to do so, subject to the following conditions:
*
* The above copyright notice and this permission notice shall be included in
* all copies or substantial portions of the Software.
*
* THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
* IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
* FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL
* THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
* LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
* OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
* THE SOFTWARE.
*/
#include "qemu/osdep.h"
#include "qemu/log.h"
#include "net/slirp.h"
#ifndef _WIN32
#include <pwd.h>
#include <sys/wait.h>
#endif
#include "net/eth.h"
#include "net/net.h"
#include "clients.h"
#include "hub.h"
#include "monitor/monitor.h"
#include "qemu/error-report.h"
#include "qemu/sockets.h"
#include <libslirp.h>
#include "chardev/char-fe.h"
#include "sysemu/sysemu.h"
#include "qemu/cutils.h"
#include "qapi/error.h"
#include "qapi/qmp/qdict.h"
#include "util.h"
#include "migration/register.h"
#include "migration/qemu-file-types.h"
static int get_str_sep(char *buf, int buf_size, const char **pp, int sep)
{
const char *p, *p1;
int len;
p = *pp;
p1 = strchr(p, sep);
if (!p1)
return -1;
len = p1 - p;
p1++;
if (buf_size > 0) {
if (len > buf_size - 1)
len = buf_size - 1;
memcpy(buf, p, len);
buf[len] = '\0';
}
*pp = p1;
return 0;
}
/* slirp network adapter */
#define SLIRP_CFG_HOSTFWD 1
struct slirp_config_str {
struct slirp_config_str *next;
int flags;
char str[1024];
};
struct GuestFwd {
CharBackend hd;
struct in_addr server;
int port;
Slirp *slirp;
};
typedef struct SlirpState {
NetClientState nc;
QTAILQ_ENTRY(SlirpState) entry;
Slirp *slirp;
Notifier poll_notifier;
Notifier exit_notifier;
#ifndef _WIN32
gchar *smb_dir;
#endif
GSList *fwd;
} SlirpState;
static struct slirp_config_str *slirp_configs;
static QTAILQ_HEAD(, SlirpState) slirp_stacks =
QTAILQ_HEAD_INITIALIZER(slirp_stacks);
static int slirp_hostfwd(SlirpState *s, const char *redir_str, Error **errp);
static int slirp_guestfwd(SlirpState *s, const char *config_str, Error **errp);
#ifndef _WIN32
static int slirp_smb(SlirpState *s, const char *exported_dir,
struct in_addr vserver_addr, Error **errp);
static void slirp_smb_cleanup(SlirpState *s);
#else
static inline void slirp_smb_cleanup(SlirpState *s) { }
#endif
static ssize_t net_slirp_send_packet(const void *pkt, size_t pkt_len,
void *opaque)
{
SlirpState *s = opaque;
uint8_t min_pkt[ETH_ZLEN];
size_t min_pktsz = sizeof(min_pkt);
if (net_peer_needs_padding(&s->nc)) {
if (eth_pad_short_frame(min_pkt, &min_pktsz, pkt, pkt_len)) {
pkt = min_pkt;
pkt_len = min_pktsz;
}
}
return qemu_send_packet(&s->nc, pkt, pkt_len);
}
static ssize_t net_slirp_receive(NetClientState *nc, const uint8_t *buf, size_t size)
{
SlirpState *s = DO_UPCAST(SlirpState, nc, nc);
slirp_input(s->slirp, buf, size);
return size;
}
static void slirp_smb_exit(Notifier *n, void *data)
{
SlirpState *s = container_of(n, SlirpState, exit_notifier);
slirp_smb_cleanup(s);
}
static void slirp_free_fwd(gpointer data)
{
struct GuestFwd *fwd = data;
qemu_chr_fe_deinit(&fwd->hd, true);
g_free(data);
}
static void net_slirp_cleanup(NetClientState *nc)
{
SlirpState *s = DO_UPCAST(SlirpState, nc, nc);
g_slist_free_full(s->fwd, slirp_free_fwd);
main_loop_poll_remove_notifier(&s->poll_notifier);
unregister_savevm(NULL, "slirp", s->slirp);
slirp_cleanup(s->slirp);
if (s->exit_notifier.notify) {
qemu_remove_exit_notifier(&s->exit_notifier);
}
slirp_smb_cleanup(s);
QTAILQ_REMOVE(&slirp_stacks, s, entry);
}
static NetClientInfo net_slirp_info = {
.type = NET_CLIENT_DRIVER_USER,
.size = sizeof(SlirpState),
.receive = net_slirp_receive,
.cleanup = net_slirp_cleanup,
};
static void net_slirp_guest_error(const char *msg, void *opaque)
{
qemu_log_mask(LOG_GUEST_ERROR, "%s", msg);
}
static int64_t net_slirp_clock_get_ns(void *opaque)
{
return qemu_clock_get_ns(QEMU_CLOCK_VIRTUAL);
}
static void *net_slirp_timer_new(SlirpTimerCb cb,
void *cb_opaque, void *opaque)
{
return timer_new_full(NULL, QEMU_CLOCK_VIRTUAL,
SCALE_MS, QEMU_TIMER_ATTR_EXTERNAL,
cb, cb_opaque);
}
static void net_slirp_timer_free(void *timer, void *opaque)
{
timer_free(timer);
}
static void net_slirp_timer_mod(void *timer, int64_t expire_timer,
void *opaque)
{
timer_mod(timer, expire_timer);
}
static void net_slirp_register_poll_fd(int fd, void *opaque)
{
qemu_fd_register(fd);
}
static void net_slirp_unregister_poll_fd(int fd, void *opaque)
{
/* no qemu_fd_unregister */
}
static void net_slirp_notify(void *opaque)
{
qemu_notify_event();
}
static const SlirpCb slirp_cb = {
.send_packet = net_slirp_send_packet,
.guest_error = net_slirp_guest_error,
.clock_get_ns = net_slirp_clock_get_ns,
.timer_new = net_slirp_timer_new,
.timer_free = net_slirp_timer_free,
.timer_mod = net_slirp_timer_mod,
.register_poll_fd = net_slirp_register_poll_fd,
.unregister_poll_fd = net_slirp_unregister_poll_fd,
.notify = net_slirp_notify,
};
static int slirp_poll_to_gio(int events)
{
int ret = 0;
if (events & SLIRP_POLL_IN) {
ret |= G_IO_IN;
}
if (events & SLIRP_POLL_OUT) {
ret |= G_IO_OUT;
}
if (events & SLIRP_POLL_PRI) {
ret |= G_IO_PRI;
}
if (events & SLIRP_POLL_ERR) {
ret |= G_IO_ERR;
}
if (events & SLIRP_POLL_HUP) {
ret |= G_IO_HUP;
}
return ret;
}
static int net_slirp_add_poll(int fd, int events, void *opaque)
{
GArray *pollfds = opaque;
GPollFD pfd = {
.fd = fd,
.events = slirp_poll_to_gio(events),
};
int idx = pollfds->len;
g_array_append_val(pollfds, pfd);
return idx;
}
static int slirp_gio_to_poll(int events)
{
int ret = 0;
if (events & G_IO_IN) {
ret |= SLIRP_POLL_IN;
}
if (events & G_IO_OUT) {
ret |= SLIRP_POLL_OUT;
}
if (events & G_IO_PRI) {
ret |= SLIRP_POLL_PRI;
}
if (events & G_IO_ERR) {
ret |= SLIRP_POLL_ERR;
}
if (events & G_IO_HUP) {
ret |= SLIRP_POLL_HUP;
}
return ret;
}
static int net_slirp_get_revents(int idx, void *opaque)
{
GArray *pollfds = opaque;
return slirp_gio_to_poll(g_array_index(pollfds, GPollFD, idx).revents);
}
static void net_slirp_poll_notify(Notifier *notifier, void *data)
{
MainLoopPoll *poll = data;
SlirpState *s = container_of(notifier, SlirpState, poll_notifier);
switch (poll->state) {
case MAIN_LOOP_POLL_FILL:
slirp_pollfds_fill(s->slirp, &poll->timeout,
net_slirp_add_poll, poll->pollfds);
break;
case MAIN_LOOP_POLL_OK:
case MAIN_LOOP_POLL_ERR:
slirp_pollfds_poll(s->slirp, poll->state == MAIN_LOOP_POLL_ERR,
net_slirp_get_revents, poll->pollfds);
break;
default:
g_assert_not_reached();
}
}
static ssize_t
net_slirp_stream_read(void *buf, size_t size, void *opaque)
{
QEMUFile *f = opaque;
return qemu_get_buffer(f, buf, size);
}
static ssize_t
net_slirp_stream_write(const void *buf, size_t size, void *opaque)
{
QEMUFile *f = opaque;
qemu_put_buffer(f, buf, size);
if (qemu_file_get_error(f)) {
return -1;
}
return size;
}
static int net_slirp_state_load(QEMUFile *f, void *opaque, int version_id)
{
Slirp *slirp = opaque;
return slirp_state_load(slirp, version_id, net_slirp_stream_read, f);
}
static void net_slirp_state_save(QEMUFile *f, void *opaque)
{
Slirp *slirp = opaque;
slirp_state_save(slirp, net_slirp_stream_write, f);
}
static SaveVMHandlers savevm_slirp_state = {
.save_state = net_slirp_state_save,
.load_state = net_slirp_state_load,
};
static int net_slirp_init(NetClientState *peer, const char *model,
const char *name, int restricted,
bool ipv4, const char *vnetwork, const char *vhost,
bool ipv6, const char *vprefix6, int vprefix6_len,
const char *vhost6,
const char *vhostname, const char *tftp_export,
const char *bootfile, const char *vdhcp_start,
const char *vnameserver, const char *vnameserver6,
const char *smb_export, const char *vsmbserver,
const char **dnssearch, const char *vdomainname,
const char *tftp_server_name,
Error **errp)
{
/* default settings according to historic slirp */
struct in_addr net = { .s_addr = htonl(0x0a000200) }; /* 10.0.2.0 */
struct in_addr mask = { .s_addr = htonl(0xffffff00) }; /* 255.255.255.0 */
struct in_addr host = { .s_addr = htonl(0x0a000202) }; /* 10.0.2.2 */
struct in_addr dhcp = { .s_addr = htonl(0x0a00020f) }; /* 10.0.2.15 */
struct in_addr dns = { .s_addr = htonl(0x0a000203) }; /* 10.0.2.3 */
struct in6_addr ip6_prefix;
struct in6_addr ip6_host;
struct in6_addr ip6_dns;
#ifndef _WIN32
struct in_addr smbsrv = { .s_addr = 0 };
#endif
NetClientState *nc;
SlirpState *s;
char buf[20];
uint32_t addr;
int shift;
char *end;
struct slirp_config_str *config;
if (!ipv4 && (vnetwork || vhost || vnameserver)) {
error_setg(errp, "IPv4 disabled but netmask/host/dns provided");
return -1;
}
if (!ipv6 && (vprefix6 || vhost6 || vnameserver6)) {
error_setg(errp, "IPv6 disabled but prefix/host6/dns6 provided");
return -1;
}
if (!ipv4 && !ipv6) {
/* It doesn't make sense to disable both */
error_setg(errp, "IPv4 and IPv6 disabled");
return -1;
}
if (vnetwork) {
if (get_str_sep(buf, sizeof(buf), &vnetwork, '/') < 0) {
if (!inet_aton(vnetwork, &net)) {
error_setg(errp, "Failed to parse netmask");
return -1;
}
addr = ntohl(net.s_addr);
if (!(addr & 0x80000000)) {
mask.s_addr = htonl(0xff000000); /* class A */
} else if ((addr & 0xfff00000) == 0xac100000) {
mask.s_addr = htonl(0xfff00000); /* priv. 172.16.0.0/12 */
} else if ((addr & 0xc0000000) == 0x80000000) {
mask.s_addr = htonl(0xffff0000); /* class B */
} else if ((addr & 0xffff0000) == 0xc0a80000) {
mask.s_addr = htonl(0xffff0000); /* priv. 192.168.0.0/16 */
} else if ((addr & 0xffff0000) == 0xc6120000) {
mask.s_addr = htonl(0xfffe0000); /* tests 198.18.0.0/15 */
} else if ((addr & 0xe0000000) == 0xe0000000) {
mask.s_addr = htonl(0xffffff00); /* class C */
} else {
mask.s_addr = htonl(0xfffffff0); /* multicast/reserved */
}
} else {
if (!inet_aton(buf, &net)) {
error_setg(errp, "Failed to parse netmask");
return -1;
}
shift = strtol(vnetwork, &end, 10);
if (*end != '\0') {
if (!inet_aton(vnetwork, &mask)) {
error_setg(errp,
"Failed to parse netmask (trailing chars)");
return -1;
}
} else if (shift < 4 || shift > 32) {
error_setg(errp,
"Invalid netmask provided (must be in range 4-32)");
return -1;
} else {
mask.s_addr = htonl(0xffffffff << (32 - shift));
}
}
net.s_addr &= mask.s_addr;
host.s_addr = net.s_addr | (htonl(0x0202) & ~mask.s_addr);
dhcp.s_addr = net.s_addr | (htonl(0x020f) & ~mask.s_addr);
dns.s_addr = net.s_addr | (htonl(0x0203) & ~mask.s_addr);
}
if (vhost && !inet_aton(vhost, &host)) {
error_setg(errp, "Failed to parse host");
return -1;
}
if ((host.s_addr & mask.s_addr) != net.s_addr) {
error_setg(errp, "Host doesn't belong to network");
return -1;
}
if (vnameserver && !inet_aton(vnameserver, &dns)) {
error_setg(errp, "Failed to parse DNS");
return -1;
}
if (restricted && (dns.s_addr & mask.s_addr) != net.s_addr) {
error_setg(errp, "DNS doesn't belong to network");
return -1;
}
if (dns.s_addr == host.s_addr) {
error_setg(errp, "DNS must be different from host");
return -1;
}
if (vdhcp_start && !inet_aton(vdhcp_start, &dhcp)) {
error_setg(errp, "Failed to parse DHCP start address");
return -1;
}
if ((dhcp.s_addr & mask.s_addr) != net.s_addr) {
error_setg(errp, "DHCP doesn't belong to network");
return -1;
}
if (dhcp.s_addr == host.s_addr || dhcp.s_addr == dns.s_addr) {
error_setg(errp, "DHCP must be different from host and DNS");
return -1;
}
#ifndef _WIN32
if (vsmbserver && !inet_aton(vsmbserver, &smbsrv)) {
error_setg(errp, "Failed to parse SMB address");
return -1;
}
#endif
if (!vprefix6) {
vprefix6 = "fec0::";
}
if (!inet_pton(AF_INET6, vprefix6, &ip6_prefix)) {
error_setg(errp, "Failed to parse IPv6 prefix");
return -1;
}
if (!vprefix6_len) {
vprefix6_len = 64;
}
if (vprefix6_len < 0 || vprefix6_len > 126) {
error_setg(errp,
"Invalid IPv6 prefix provided "
"(IPv6 prefix length must be between 0 and 126)");
return -1;
}
if (vhost6) {
if (!inet_pton(AF_INET6, vhost6, &ip6_host)) {
error_setg(errp, "Failed to parse IPv6 host");
return -1;
}
if (!in6_equal_net(&ip6_prefix, &ip6_host, vprefix6_len)) {
error_setg(errp, "IPv6 Host doesn't belong to network");
return -1;
}
} else {
ip6_host = ip6_prefix;
ip6_host.s6_addr[15] |= 2;
}
if (vnameserver6) {
if (!inet_pton(AF_INET6, vnameserver6, &ip6_dns)) {
error_setg(errp, "Failed to parse IPv6 DNS");
return -1;
}
if (restricted && !in6_equal_net(&ip6_prefix, &ip6_dns, vprefix6_len)) {
error_setg(errp, "IPv6 DNS doesn't belong to network");
return -1;
}
} else {
ip6_dns = ip6_prefix;
ip6_dns.s6_addr[15] |= 3;
}
if (vdomainname && !*vdomainname) {
error_setg(errp, "'domainname' parameter cannot be empty");
return -1;
}
if (vdomainname && strlen(vdomainname) > 255) {
error_setg(errp, "'domainname' parameter cannot exceed 255 bytes");
return -1;
}
if (vhostname && strlen(vhostname) > 255) {
error_setg(errp, "'vhostname' parameter cannot exceed 255 bytes");
return -1;
}
if (tftp_server_name && strlen(tftp_server_name) > 255) {
error_setg(errp, "'tftp-server-name' parameter cannot exceed 255 bytes");
return -1;
}
nc = qemu_new_net_client(&net_slirp_info, peer, model, name);
snprintf(nc->info_str, sizeof(nc->info_str),
"net=%s,restrict=%s", inet_ntoa(net),
restricted ? "on" : "off");
s = DO_UPCAST(SlirpState, nc, nc);
s->slirp = slirp_init(restricted, ipv4, net, mask, host,
ipv6, ip6_prefix, vprefix6_len, ip6_host,
vhostname, tftp_server_name,
tftp_export, bootfile, dhcp,
dns, ip6_dns, dnssearch, vdomainname,
&slirp_cb, s);
QTAILQ_INSERT_TAIL(&slirp_stacks, s, entry);
/*
* Make sure the current bitstream version of slirp is 4, to avoid
* QEMU migration incompatibilities, if upstream slirp bumped the
* version.
*
* FIXME: use bitfields of features? teach libslirp to save with
* specific version?
*/
g_assert(slirp_state_version() == 4);
register_savevm_live("slirp", 0, slirp_state_version(),
&savevm_slirp_state, s->slirp);
s->poll_notifier.notify = net_slirp_poll_notify;
main_loop_poll_add_notifier(&s->poll_notifier);
for (config = slirp_configs; config; config = config->next) {
if (config->flags & SLIRP_CFG_HOSTFWD) {
if (slirp_hostfwd(s, config->str, errp) < 0) {
goto error;
}
} else {
if (slirp_guestfwd(s, config->str, errp) < 0) {
goto error;
}
}
}
#ifndef _WIN32
if (smb_export) {
if (slirp_smb(s, smb_export, smbsrv, errp) < 0) {
goto error;
}
}
#endif
s->exit_notifier.notify = slirp_smb_exit;
qemu_add_exit_notifier(&s->exit_notifier);
return 0;
error:
qemu_del_net_client(nc);
return -1;
}
static SlirpState *slirp_lookup(Monitor *mon, const char *id)
{
if (id) {
NetClientState *nc = qemu_find_netdev(id);
if (!nc) {
monitor_printf(mon, "unrecognized netdev id '%s'\n", id);
return NULL;
}
if (strcmp(nc->model, "user")) {
monitor_printf(mon, "invalid device specified\n");
return NULL;
}
return DO_UPCAST(SlirpState, nc, nc);
} else {
if (QTAILQ_EMPTY(&slirp_stacks)) {
monitor_printf(mon, "user mode network stack not in use\n");
return NULL;
}
return QTAILQ_FIRST(&slirp_stacks);
}
}
void hmp_hostfwd_remove(Monitor *mon, const QDict *qdict)
{
struct in_addr host_addr = { .s_addr = INADDR_ANY };
int host_port;
char buf[256];
const char *src_str, *p;
SlirpState *s;
int is_udp = 0;
int err;
const char *arg1 = qdict_get_str(qdict, "arg1");
const char *arg2 = qdict_get_try_str(qdict, "arg2");
if (arg2) {
s = slirp_lookup(mon, arg1);
src_str = arg2;
} else {
s = slirp_lookup(mon, NULL);
src_str = arg1;
}
if (!s) {
return;
}
p = src_str;
if (!p || get_str_sep(buf, sizeof(buf), &p, ':') < 0) {
goto fail_syntax;
}
if (!strcmp(buf, "tcp") || buf[0] == '\0') {
is_udp = 0;
} else if (!strcmp(buf, "udp")) {
is_udp = 1;
} else {
goto fail_syntax;
}
if (get_str_sep(buf, sizeof(buf), &p, ':') < 0) {
goto fail_syntax;
}
if (buf[0] != '\0' && !inet_aton(buf, &host_addr)) {
goto fail_syntax;
}
if (qemu_strtoi(p, NULL, 10, &host_port)) {
goto fail_syntax;
}
err = slirp_remove_hostfwd(s->slirp, is_udp, host_addr, host_port);
monitor_printf(mon, "host forwarding rule for %s %s\n", src_str,
err ? "not found" : "removed");
return;
fail_syntax:
monitor_printf(mon, "invalid format\n");
}
static int slirp_hostfwd(SlirpState *s, const char *redir_str, Error **errp)
{
struct in_addr host_addr = { .s_addr = INADDR_ANY };
struct in_addr guest_addr = { .s_addr = 0 };
int host_port, guest_port;
const char *p;
char buf[256];
int is_udp;
char *end;
const char *fail_reason = "Unknown reason";
p = redir_str;
if (!p || get_str_sep(buf, sizeof(buf), &p, ':') < 0) {
fail_reason = "No : separators";
goto fail_syntax;
}
if (!strcmp(buf, "tcp") || buf[0] == '\0') {
is_udp = 0;
} else if (!strcmp(buf, "udp")) {
is_udp = 1;
} else {
fail_reason = "Bad protocol name";
goto fail_syntax;
}
if (get_str_sep(buf, sizeof(buf), &p, ':') < 0) {
fail_reason = "Missing : separator";
goto fail_syntax;
}
if (buf[0] != '\0' && !inet_aton(buf, &host_addr)) {
fail_reason = "Bad host address";
goto fail_syntax;
}
if (get_str_sep(buf, sizeof(buf), &p, '-') < 0) {
fail_reason = "Bad host port separator";
goto fail_syntax;
}
host_port = strtol(buf, &end, 0);
if (*end != '\0' || host_port < 0 || host_port > 65535) {
fail_reason = "Bad host port";
goto fail_syntax;
}
if (get_str_sep(buf, sizeof(buf), &p, ':') < 0) {
fail_reason = "Missing guest address";
goto fail_syntax;
}
if (buf[0] != '\0' && !inet_aton(buf, &guest_addr)) {
fail_reason = "Bad guest address";
goto fail_syntax;
}
guest_port = strtol(p, &end, 0);
if (*end != '\0' || guest_port < 1 || guest_port > 65535) {
fail_reason = "Bad guest port";
goto fail_syntax;
}
if (slirp_add_hostfwd(s->slirp, is_udp, host_addr, host_port, guest_addr,
guest_port) < 0) {
error_setg(errp, "Could not set up host forwarding rule '%s'",
redir_str);
return -1;
}
return 0;
fail_syntax:
error_setg(errp, "Invalid host forwarding rule '%s' (%s)", redir_str,
fail_reason);
return -1;
}
void hmp_hostfwd_add(Monitor *mon, const QDict *qdict)
{
const char *redir_str;
SlirpState *s;
const char *arg1 = qdict_get_str(qdict, "arg1");
const char *arg2 = qdict_get_try_str(qdict, "arg2");
if (arg2) {
s = slirp_lookup(mon, arg1);
redir_str = arg2;
} else {
s = slirp_lookup(mon, NULL);
redir_str = arg1;
}
if (s) {
Error *err = NULL;
if (slirp_hostfwd(s, redir_str, &err) < 0) {
error_report_err(err);
}
}
}
#ifndef _WIN32
/* automatic user mode samba server configuration */
static void slirp_smb_cleanup(SlirpState *s)
{
int ret;
if (s->smb_dir) {
gchar *cmd = g_strdup_printf("rm -rf %s", s->smb_dir);
ret = system(cmd);
if (ret == -1 || !WIFEXITED(ret)) {
error_report("'%s' failed.", cmd);
} else if (WEXITSTATUS(ret)) {
error_report("'%s' failed. Error code: %d",
cmd, WEXITSTATUS(ret));
}
g_free(cmd);
g_free(s->smb_dir);
s->smb_dir = NULL;
}
}
static int slirp_smb(SlirpState* s, const char *exported_dir,
struct in_addr vserver_addr, Error **errp)
{
char *smb_conf;
char *smb_cmdline;
struct passwd *passwd;
FILE *f;
passwd = getpwuid(geteuid());
if (!passwd) {
error_setg(errp, "Failed to retrieve user name");
return -1;
}
if (access(CONFIG_SMBD_COMMAND, F_OK)) {
error_setg(errp, "Could not find '%s', please install it",
CONFIG_SMBD_COMMAND);
return -1;
}
if (access(exported_dir, R_OK | X_OK)) {
error_setg(errp, "Error accessing shared directory '%s': %s",
exported_dir, strerror(errno));
return -1;
}
s->smb_dir = g_dir_make_tmp("qemu-smb.XXXXXX", NULL);
if (!s->smb_dir) {
error_setg(errp, "Could not create samba server dir");
return -1;
}
smb_conf = g_strdup_printf("%s/%s", s->smb_dir, "smb.conf");
f = fopen(smb_conf, "w");
if (!f) {
slirp_smb_cleanup(s);
error_setg(errp,
"Could not create samba server configuration file '%s'",
smb_conf);
g_free(smb_conf);
return -1;
}
fprintf(f,
"[global]\n"
"private dir=%s\n"
"interfaces=127.0.0.1\n"
"bind interfaces only=yes\n"
"pid directory=%s\n"
"lock directory=%s\n"
"state directory=%s\n"
"cache directory=%s\n"
"ncalrpc dir=%s/ncalrpc\n"
"log file=%s/log.smbd\n"
"smb passwd file=%s/smbpasswd\n"
"security = user\n"
"map to guest = Bad User\n"
"load printers = no\n"
"printing = bsd\n"
"disable spoolss = yes\n"
"usershare max shares = 0\n"
"[qemu]\n"
"path=%s\n"
"read only=no\n"
"guest ok=yes\n"
"force user=%s\n",
s->smb_dir,
s->smb_dir,
s->smb_dir,
s->smb_dir,
s->smb_dir,
s->smb_dir,
s->smb_dir,
s->smb_dir,
exported_dir,
passwd->pw_name
);
fclose(f);
smb_cmdline = g_strdup_printf("%s -l %s -s %s",
CONFIG_SMBD_COMMAND, s->smb_dir, smb_conf);
g_free(smb_conf);
if (slirp_add_exec(s->slirp, smb_cmdline, &vserver_addr, 139) < 0 ||
slirp_add_exec(s->slirp, smb_cmdline, &vserver_addr, 445) < 0) {
slirp_smb_cleanup(s);
g_free(smb_cmdline);
error_setg(errp, "Conflicting/invalid smbserver address");
return -1;
}
g_free(smb_cmdline);
return 0;
}
#endif /* !defined(_WIN32) */
static int guestfwd_can_read(void *opaque)
{
struct GuestFwd *fwd = opaque;
return slirp_socket_can_recv(fwd->slirp, fwd->server, fwd->port);
}
static void guestfwd_read(void *opaque, const uint8_t *buf, int size)
{
struct GuestFwd *fwd = opaque;
slirp_socket_recv(fwd->slirp, fwd->server, fwd->port, buf, size);
}
static ssize_t guestfwd_write(const void *buf, size_t len, void *chr)
{
return qemu_chr_fe_write_all(chr, buf, len);
}
static int slirp_guestfwd(SlirpState *s, const char *config_str, Error **errp)
{
/* TODO: IPv6 */
struct in_addr server = { .s_addr = 0 };
struct GuestFwd *fwd;
const char *p;
char buf[128];
char *end;
int port;
p = config_str;
if (get_str_sep(buf, sizeof(buf), &p, ':') < 0) {
goto fail_syntax;
}
if (strcmp(buf, "tcp") && buf[0] != '\0') {
goto fail_syntax;
}
if (get_str_sep(buf, sizeof(buf), &p, ':') < 0) {
goto fail_syntax;
}
if (buf[0] != '\0' && !inet_aton(buf, &server)) {
goto fail_syntax;
}
if (get_str_sep(buf, sizeof(buf), &p, '-') < 0) {
goto fail_syntax;
}
port = strtol(buf, &end, 10);
if (*end != '\0' || port < 1 || port > 65535) {
goto fail_syntax;
}
snprintf(buf, sizeof(buf), "guestfwd.tcp.%d", port);
if (g_str_has_prefix(p, "cmd:")) {
if (slirp_add_exec(s->slirp, &p[4], &server, port) < 0) {
error_setg(errp, "Conflicting/invalid host:port in guest "
"forwarding rule '%s'", config_str);
return -1;
}
} else {
Error *err = NULL;
/*
* FIXME: sure we want to support implicit
* muxed monitors here?
*/
Chardev *chr = qemu_chr_new_mux_mon(buf, p, NULL);
if (!chr) {
error_setg(errp, "Could not open guest forwarding device '%s'",
buf);
return -1;
}
fwd = g_new(struct GuestFwd, 1);
qemu_chr_fe_init(&fwd->hd, chr, &err);
if (err) {
error_propagate(errp, err);
object_unparent(OBJECT(chr));
g_free(fwd);
return -1;
}
if (slirp_add_guestfwd(s->slirp, guestfwd_write, &fwd->hd,
&server, port) < 0) {
error_setg(errp, "Conflicting/invalid host:port in guest "
"forwarding rule '%s'", config_str);
qemu_chr_fe_deinit(&fwd->hd, true);
g_free(fwd);
return -1;
}
fwd->server = server;
fwd->port = port;
fwd->slirp = s->slirp;
qemu_chr_fe_set_handlers(&fwd->hd, guestfwd_can_read, guestfwd_read,
NULL, NULL, fwd, NULL, true);
s->fwd = g_slist_append(s->fwd, fwd);
}
return 0;
fail_syntax:
error_setg(errp, "Invalid guest forwarding rule '%s'", config_str);
return -1;
}
void hmp_info_usernet(Monitor *mon, const QDict *qdict)
{
SlirpState *s;
QTAILQ_FOREACH(s, &slirp_stacks, entry) {
int id;
bool got_hub_id = net_hub_id_for_client(&s->nc, &id) == 0;
char *info = slirp_connection_info(s->slirp);
monitor_printf(mon, "Hub %d (%s):\n%s",
got_hub_id ? id : -1,
s->nc.name, info);
g_free(info);
}
}
static void
net_init_slirp_configs(const StringList *fwd, int flags)
{
while (fwd) {
struct slirp_config_str *config;
config = g_malloc0(sizeof(*config));
pstrcpy(config->str, sizeof(config->str), fwd->value->str);
config->flags = flags;
config->next = slirp_configs;
slirp_configs = config;
fwd = fwd->next;
}
}
static const char **slirp_dnssearch(const StringList *dnsname)
{
const StringList *c = dnsname;
size_t i = 0, num_opts = 0;
const char **ret;
while (c) {
num_opts++;
c = c->next;
}
if (num_opts == 0) {
return NULL;
}
ret = g_malloc((num_opts + 1) * sizeof(*ret));
c = dnsname;
while (c) {
ret[i++] = c->value->str;
c = c->next;
}
ret[i] = NULL;
return ret;
}
int net_init_slirp(const Netdev *netdev, const char *name,
NetClientState *peer, Error **errp)
{
struct slirp_config_str *config;
char *vnet;
int ret;
const NetdevUserOptions *user;
const char **dnssearch;
bool ipv4 = true, ipv6 = true;
assert(netdev->type == NET_CLIENT_DRIVER_USER);
user = &netdev->u.user;
if ((user->has_ipv6 && user->ipv6 && !user->has_ipv4) ||
(user->has_ipv4 && !user->ipv4)) {
ipv4 = 0;
}
if ((user->has_ipv4 && user->ipv4 && !user->has_ipv6) ||
(user->has_ipv6 && !user->ipv6)) {
ipv6 = 0;
}
vnet = user->has_net ? g_strdup(user->net) :
user->has_ip ? g_strdup_printf("%s/24", user->ip) :
NULL;
dnssearch = slirp_dnssearch(user->dnssearch);
/* all optional fields are initialized to "all bits zero" */
net_init_slirp_configs(user->hostfwd, SLIRP_CFG_HOSTFWD);
net_init_slirp_configs(user->guestfwd, 0);
ret = net_slirp_init(peer, "user", name, user->q_restrict,
ipv4, vnet, user->host,
ipv6, user->ipv6_prefix, user->ipv6_prefixlen,
user->ipv6_host, user->hostname, user->tftp,
user->bootfile, user->dhcpstart,
user->dns, user->ipv6_dns, user->smb,
user->smbserver, dnssearch, user->domainname,
user->tftp_server_name, errp);
while (slirp_configs) {
config = slirp_configs;
slirp_configs = config->next;
g_free(config);
}
g_free(vnet);
g_free(dnssearch);
return ret;
}