qemu/net/slirp.c

1125 lines
31 KiB
C
Raw Normal View History

/*
* 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"
#if defined(CONFIG_SLIRP_SMBD)
#include <pwd.h>
#include <sys/wait.h>
#endif
net: Pad short frames to minimum size before sending from SLiRP/TAP The minimum Ethernet frame length is 60 bytes. For short frames with smaller length like ARP packets (only 42 bytes), on a real world NIC it can choose either padding its length to the minimum required 60 bytes, or sending it out directly to the wire. Such behavior can be hardcoded or controled by a register bit. Similarly on the receive path, NICs can choose either dropping such short frames directly or handing them over to software to handle. On the other hand, for the network backends like SLiRP/TAP, they don't expose a way to control the short frame behavior. As of today they just send/receive data from/to the other end connected to them, which means any sized packet is acceptable. So they can send and receive short frames without any problem. It is observed that ARP packets sent from SLiRP/TAP are 42 bytes, and SLiRP/TAP just send these ARP packets to the other end which might be a NIC model that does not allow short frames to pass through. To provide better compatibility, for packets sent from QEMU network backends like SLiRP/TAP, we change to pad short frames before sending it out to the other end, if the other end does not forbid it via the nc->do_not_pad flag. This ensures a backend as an Ethernet sender does not violate the spec. But with this change, the behavior of dropping short frames from SLiRP/TAP interfaces in the NIC model cannot be emulated because it always receives a packet that is spec complaint. The capability of sending short frames from NIC models is still supported and short frames can still pass through SLiRP/TAP. This commit should be able to fix the issue as reported with some NIC models before, that ARP requests get dropped, preventing the guest from becoming visible on the network. It was workarounded in these NIC models on the receive path, that when a short frame is received, it is padded up to 60 bytes. The following 2 commits seem to be the one to workaround this issue in e1000 and vmxenet3 before, and should probably be reverted. commit 78aeb23eded2 ("e1000: Pad short frames to minimum size (60 bytes)") commit 40a87c6c9b11 ("vmxnet3: Pad short frames to minimum size (60 bytes)") Signed-off-by: Bin Meng <bmeng.cn@gmail.com> Reviewed-by: Philippe Mathieu-Daudé <philmd@redhat.com> Signed-off-by: Jason Wang <jasowang@redhat.com>
2021-03-17 09:26:29 +03:00
#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;
#if defined(CONFIG_SLIRP_SMBD)
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);
#if defined(CONFIG_SLIRP_SMBD)
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;
net: Pad short frames to minimum size before sending from SLiRP/TAP The minimum Ethernet frame length is 60 bytes. For short frames with smaller length like ARP packets (only 42 bytes), on a real world NIC it can choose either padding its length to the minimum required 60 bytes, or sending it out directly to the wire. Such behavior can be hardcoded or controled by a register bit. Similarly on the receive path, NICs can choose either dropping such short frames directly or handing them over to software to handle. On the other hand, for the network backends like SLiRP/TAP, they don't expose a way to control the short frame behavior. As of today they just send/receive data from/to the other end connected to them, which means any sized packet is acceptable. So they can send and receive short frames without any problem. It is observed that ARP packets sent from SLiRP/TAP are 42 bytes, and SLiRP/TAP just send these ARP packets to the other end which might be a NIC model that does not allow short frames to pass through. To provide better compatibility, for packets sent from QEMU network backends like SLiRP/TAP, we change to pad short frames before sending it out to the other end, if the other end does not forbid it via the nc->do_not_pad flag. This ensures a backend as an Ethernet sender does not violate the spec. But with this change, the behavior of dropping short frames from SLiRP/TAP interfaces in the NIC model cannot be emulated because it always receives a packet that is spec complaint. The capability of sending short frames from NIC models is still supported and short frames can still pass through SLiRP/TAP. This commit should be able to fix the issue as reported with some NIC models before, that ARP requests get dropped, preventing the guest from becoming visible on the network. It was workarounded in these NIC models on the receive path, that when a short frame is received, it is padded up to 60 bytes. The following 2 commits seem to be the one to workaround this issue in e1000 and vmxenet3 before, and should probably be reverted. commit 78aeb23eded2 ("e1000: Pad short frames to minimum size (60 bytes)") commit 40a87c6c9b11 ("vmxnet3: Pad short frames to minimum size (60 bytes)") Signed-off-by: Bin Meng <bmeng.cn@gmail.com> Reviewed-by: Philippe Mathieu-Daudé <philmd@redhat.com> Signed-off-by: Jason Wang <jasowang@redhat.com>
2021-03-17 09:26:29 +03:00
uint8_t min_pkt[ETH_ZLEN];
size_t min_pktsz = sizeof(min_pkt);
if (net_peer_needs_padding(&s->nc)) {
net: Pad short frames to minimum size before sending from SLiRP/TAP The minimum Ethernet frame length is 60 bytes. For short frames with smaller length like ARP packets (only 42 bytes), on a real world NIC it can choose either padding its length to the minimum required 60 bytes, or sending it out directly to the wire. Such behavior can be hardcoded or controled by a register bit. Similarly on the receive path, NICs can choose either dropping such short frames directly or handing them over to software to handle. On the other hand, for the network backends like SLiRP/TAP, they don't expose a way to control the short frame behavior. As of today they just send/receive data from/to the other end connected to them, which means any sized packet is acceptable. So they can send and receive short frames without any problem. It is observed that ARP packets sent from SLiRP/TAP are 42 bytes, and SLiRP/TAP just send these ARP packets to the other end which might be a NIC model that does not allow short frames to pass through. To provide better compatibility, for packets sent from QEMU network backends like SLiRP/TAP, we change to pad short frames before sending it out to the other end, if the other end does not forbid it via the nc->do_not_pad flag. This ensures a backend as an Ethernet sender does not violate the spec. But with this change, the behavior of dropping short frames from SLiRP/TAP interfaces in the NIC model cannot be emulated because it always receives a packet that is spec complaint. The capability of sending short frames from NIC models is still supported and short frames can still pass through SLiRP/TAP. This commit should be able to fix the issue as reported with some NIC models before, that ARP requests get dropped, preventing the guest from becoming visible on the network. It was workarounded in these NIC models on the receive path, that when a short frame is received, it is padded up to 60 bytes. The following 2 commits seem to be the one to workaround this issue in e1000 and vmxenet3 before, and should probably be reverted. commit 78aeb23eded2 ("e1000: Pad short frames to minimum size (60 bytes)") commit 40a87c6c9b11 ("vmxnet3: Pad short frames to minimum size (60 bytes)") Signed-off-by: Bin Meng <bmeng.cn@gmail.com> Reviewed-by: Philippe Mathieu-Daudé <philmd@redhat.com> Signed-off-by: Jason Wang <jasowang@redhat.com>
2021-03-17 09:26:29 +03:00
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 = {
qapi: Change Netdev into a flat union This is a mostly-mechanical conversion that creates a new flat union 'Netdev' QAPI type that covers all the branches of the former 'NetClientOptions' simple union, where the branches are now listed in a new 'NetClientDriver' enum rather than generated from the simple union. The existence of a flat union has no change to the command line syntax accepted for new code, and will make it possible for a future patch to switch the QMP command to parse a boxed union for no change to valid QMP; but it does have some ripple effect on the C code when dealing with the new types. While making the conversion, note that the 'NetLegacy' type remains unchanged: it applies only to legacy command line options, and will not be ported to QMP, so it should remain a wrapper around a simple union; to avoid confusion, the type named 'NetClientOptions' is now gone, and we introduce 'NetLegacyOptions' in its place. Then, in the C code, we convert from NetLegacy to Netdev as soon as possible, so that the bulk of the net stack only has to deal with one QAPI type, not two. Note that since the old legacy code always rejected 'hubport', we can just omit that branch from the new 'NetLegacyOptions' simple union. Based on an idea originally by Zoltán Kővágó <DirtY.iCE.hu@gmail.com>: Message-Id: <01a527fbf1a5de880091f98cf011616a78adeeee.1441627176.git.DirtY.iCE.hu@gmail.com> although the sed script in that patch no longer applies due to other changes in the tree since then, and I also did some manual cleanups (such as fixing whitespace to keep checkpatch happy). Signed-off-by: Eric Blake <eblake@redhat.com> Message-Id: <1468468228-27827-13-git-send-email-eblake@redhat.com> Reviewed-by: Markus Armbruster <armbru@redhat.com> [Fixup from Eric squashed in] Signed-off-by: Markus Armbruster <armbru@redhat.com>
2016-07-14 06:50:23 +03:00
.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;
#if defined(CONFIG_SLIRP_SMBD)
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;
}
#if defined(CONFIG_SLIRP_SMBD)
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;
}
}
}
#if defined(CONFIG_SLIRP_SMBD)
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);
}
}
}
#if defined(CONFIG_SLIRP_SMBD)
/* 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(CONFIG_SLIRP_SMBD) */
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;
chardev: mark the calls that allow an implicit mux monitor This is mostly for readability of the code. Let's make it clear which callers can create an implicit monitor when the chardev is muxed. This will also enforce a safer behaviour, as we don't really support creating monitor anywhere/anytime at the moment. Add an assert() to make sure the programmer explicitely wanted that behaviour. There are documented cases, such as: -serial/-parallel/-virtioconsole and to less extent -debugcon. Less obvious and questionable ones are -gdb, SLIRP -guestfwd and Xen console. Add a FIXME note for those, but keep the support for now. Other qemu_chr_new() callers either have a fixed parameter/filename string or do not need it, such as -qtest: * qtest.c: qtest_init() Afaik, only used by tests/libqtest.c, without mux. I don't think we support it outside of qemu testing: drop support for implicit mux monitor (qemu_chr_new() call: no implicit mux now). * hw/ All with literal @filename argument that doesn't enable mux monitor. * tests/ All with @filename argument that doesn't enable mux monitor. On a related note, the list of monitor creation places: - the chardev creators listed above: all from command line (except perhaps Xen console?) - -gdb & hmp gdbserver will create a "GDB monitor command" chardev that is wired to an HMP monitor. - -mon command line option From this short study, I would like to think that a monitor may only be created in the main thread today, though I remain skeptical :) Signed-off-by: Marc-André Lureau <marcandre.lureau@redhat.com> Reviewed-by: Markus Armbruster <armbru@redhat.com>
2018-08-22 20:19:42 +03:00
/*
* 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;
qapi: Change Netdev into a flat union This is a mostly-mechanical conversion that creates a new flat union 'Netdev' QAPI type that covers all the branches of the former 'NetClientOptions' simple union, where the branches are now listed in a new 'NetClientDriver' enum rather than generated from the simple union. The existence of a flat union has no change to the command line syntax accepted for new code, and will make it possible for a future patch to switch the QMP command to parse a boxed union for no change to valid QMP; but it does have some ripple effect on the C code when dealing with the new types. While making the conversion, note that the 'NetLegacy' type remains unchanged: it applies only to legacy command line options, and will not be ported to QMP, so it should remain a wrapper around a simple union; to avoid confusion, the type named 'NetClientOptions' is now gone, and we introduce 'NetLegacyOptions' in its place. Then, in the C code, we convert from NetLegacy to Netdev as soon as possible, so that the bulk of the net stack only has to deal with one QAPI type, not two. Note that since the old legacy code always rejected 'hubport', we can just omit that branch from the new 'NetLegacyOptions' simple union. Based on an idea originally by Zoltán Kővágó <DirtY.iCE.hu@gmail.com>: Message-Id: <01a527fbf1a5de880091f98cf011616a78adeeee.1441627176.git.DirtY.iCE.hu@gmail.com> although the sed script in that patch no longer applies due to other changes in the tree since then, and I also did some manual cleanups (such as fixing whitespace to keep checkpatch happy). Signed-off-by: Eric Blake <eblake@redhat.com> Message-Id: <1468468228-27827-13-git-send-email-eblake@redhat.com> Reviewed-by: Markus Armbruster <armbru@redhat.com> [Fixup from Eric squashed in] Signed-off-by: Markus Armbruster <armbru@redhat.com>
2016-07-14 06:50:23 +03:00
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;
}