qemu-e2k/slirp/slirp.c
James Clarke b0060110aa slirp: Send window updates to guest after window was closed
If the receive window presented to the guest closes, slirp should send a
window update once the window reopens sufficiently, rather than forcing
the guest to send a window probe, which can take several seconds.

Signed-off-by: James Clarke <jrtc27@jrtc27.com>
Signed-off-by: Samuel Thibault <samuel.thibault@ens-lyon.org>
2018-05-31 21:19:24 +02:00

1494 lines
46 KiB
C

/*
* libslirp glue
*
* Copyright (c) 2004-2008 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-common.h"
#include "qemu/timer.h"
#include "qemu/error-report.h"
#include "chardev/char-fe.h"
#include "migration/register.h"
#include "slirp.h"
#include "hw/hw.h"
#include "qemu/cutils.h"
#ifndef _WIN32
#include <net/if.h>
#endif
/* host loopback address */
struct in_addr loopback_addr;
/* host loopback network mask */
unsigned long loopback_mask;
/* emulated hosts use the MAC addr 52:55:IP:IP:IP:IP */
static const uint8_t special_ethaddr[ETH_ALEN] = {
0x52, 0x55, 0x00, 0x00, 0x00, 0x00
};
u_int curtime;
static QTAILQ_HEAD(slirp_instances, Slirp) slirp_instances =
QTAILQ_HEAD_INITIALIZER(slirp_instances);
static struct in_addr dns_addr;
#ifndef _WIN32
static struct in6_addr dns6_addr;
#endif
static u_int dns_addr_time;
#ifndef _WIN32
static u_int dns6_addr_time;
#endif
#define TIMEOUT_FAST 2 /* milliseconds */
#define TIMEOUT_SLOW 499 /* milliseconds */
/* for the aging of certain requests like DNS */
#define TIMEOUT_DEFAULT 1000 /* milliseconds */
#ifdef _WIN32
int get_dns_addr(struct in_addr *pdns_addr)
{
FIXED_INFO *FixedInfo=NULL;
ULONG BufLen;
DWORD ret;
IP_ADDR_STRING *pIPAddr;
struct in_addr tmp_addr;
if (dns_addr.s_addr != 0 && (curtime - dns_addr_time) < TIMEOUT_DEFAULT) {
*pdns_addr = dns_addr;
return 0;
}
FixedInfo = (FIXED_INFO *)GlobalAlloc(GPTR, sizeof(FIXED_INFO));
BufLen = sizeof(FIXED_INFO);
if (ERROR_BUFFER_OVERFLOW == GetNetworkParams(FixedInfo, &BufLen)) {
if (FixedInfo) {
GlobalFree(FixedInfo);
FixedInfo = NULL;
}
FixedInfo = GlobalAlloc(GPTR, BufLen);
}
if ((ret = GetNetworkParams(FixedInfo, &BufLen)) != ERROR_SUCCESS) {
printf("GetNetworkParams failed. ret = %08x\n", (u_int)ret );
if (FixedInfo) {
GlobalFree(FixedInfo);
FixedInfo = NULL;
}
return -1;
}
pIPAddr = &(FixedInfo->DnsServerList);
inet_aton(pIPAddr->IpAddress.String, &tmp_addr);
*pdns_addr = tmp_addr;
dns_addr = tmp_addr;
dns_addr_time = curtime;
if (FixedInfo) {
GlobalFree(FixedInfo);
FixedInfo = NULL;
}
return 0;
}
int get_dns6_addr(struct in6_addr *pdns6_addr, uint32_t *scope_id)
{
return -1;
}
static void winsock_cleanup(void)
{
WSACleanup();
}
#else
static int get_dns_addr_cached(void *pdns_addr, void *cached_addr,
socklen_t addrlen,
struct stat *cached_stat, u_int *cached_time)
{
struct stat old_stat;
if (curtime - *cached_time < TIMEOUT_DEFAULT) {
memcpy(pdns_addr, cached_addr, addrlen);
return 0;
}
old_stat = *cached_stat;
if (stat("/etc/resolv.conf", cached_stat) != 0) {
return -1;
}
if (cached_stat->st_dev == old_stat.st_dev
&& cached_stat->st_ino == old_stat.st_ino
&& cached_stat->st_size == old_stat.st_size
&& cached_stat->st_mtime == old_stat.st_mtime) {
memcpy(pdns_addr, cached_addr, addrlen);
return 0;
}
return 1;
}
static int get_dns_addr_resolv_conf(int af, void *pdns_addr, void *cached_addr,
socklen_t addrlen, uint32_t *scope_id,
u_int *cached_time)
{
char buff[512];
char buff2[257];
FILE *f;
int found = 0;
void *tmp_addr = alloca(addrlen);
unsigned if_index;
f = fopen("/etc/resolv.conf", "r");
if (!f)
return -1;
#ifdef DEBUG
fprintf(stderr, "IP address of your DNS(s): ");
#endif
while (fgets(buff, 512, f) != NULL) {
if (sscanf(buff, "nameserver%*[ \t]%256s", buff2) == 1) {
char *c = strchr(buff2, '%');
if (c) {
if_index = if_nametoindex(c + 1);
*c = '\0';
} else {
if_index = 0;
}
if (!inet_pton(af, buff2, tmp_addr)) {
continue;
}
/* If it's the first one, set it to dns_addr */
if (!found) {
memcpy(pdns_addr, tmp_addr, addrlen);
memcpy(cached_addr, tmp_addr, addrlen);
if (scope_id) {
*scope_id = if_index;
}
*cached_time = curtime;
}
#ifdef DEBUG
else
fprintf(stderr, ", ");
#endif
if (++found > 3) {
#ifdef DEBUG
fprintf(stderr, "(more)");
#endif
break;
}
#ifdef DEBUG
else {
char s[INET6_ADDRSTRLEN];
const char *res = inet_ntop(af, tmp_addr, s, sizeof(s));
if (!res) {
res = "(string conversion error)";
}
fprintf(stderr, "%s", res);
}
#endif
}
}
fclose(f);
if (!found)
return -1;
return 0;
}
int get_dns_addr(struct in_addr *pdns_addr)
{
static struct stat dns_addr_stat;
if (dns_addr.s_addr != 0) {
int ret;
ret = get_dns_addr_cached(pdns_addr, &dns_addr, sizeof(dns_addr),
&dns_addr_stat, &dns_addr_time);
if (ret <= 0) {
return ret;
}
}
return get_dns_addr_resolv_conf(AF_INET, pdns_addr, &dns_addr,
sizeof(dns_addr), NULL, &dns_addr_time);
}
int get_dns6_addr(struct in6_addr *pdns6_addr, uint32_t *scope_id)
{
static struct stat dns6_addr_stat;
if (!in6_zero(&dns6_addr)) {
int ret;
ret = get_dns_addr_cached(pdns6_addr, &dns6_addr, sizeof(dns6_addr),
&dns6_addr_stat, &dns6_addr_time);
if (ret <= 0) {
return ret;
}
}
return get_dns_addr_resolv_conf(AF_INET6, pdns6_addr, &dns6_addr,
sizeof(dns6_addr),
scope_id, &dns6_addr_time);
}
#endif
static void slirp_init_once(void)
{
static int initialized;
#ifdef _WIN32
WSADATA Data;
#endif
if (initialized) {
return;
}
initialized = 1;
#ifdef _WIN32
WSAStartup(MAKEWORD(2,0), &Data);
atexit(winsock_cleanup);
#endif
loopback_addr.s_addr = htonl(INADDR_LOOPBACK);
loopback_mask = htonl(IN_CLASSA_NET);
}
static void slirp_state_save(QEMUFile *f, void *opaque);
static int slirp_state_load(QEMUFile *f, void *opaque, int version_id);
static SaveVMHandlers savevm_slirp_state = {
.save_state = slirp_state_save,
.load_state = slirp_state_load,
};
Slirp *slirp_init(int restricted, bool in_enabled, struct in_addr vnetwork,
struct in_addr vnetmask, struct in_addr vhost,
bool in6_enabled,
struct in6_addr vprefix_addr6, uint8_t vprefix_len,
struct in6_addr vhost6, const char *vhostname,
const char *tftp_path, const char *bootfile,
struct in_addr vdhcp_start, struct in_addr vnameserver,
struct in6_addr vnameserver6, const char **vdnssearch,
const char *vdomainname, void *opaque)
{
Slirp *slirp = g_malloc0(sizeof(Slirp));
slirp_init_once();
slirp->grand = g_rand_new();
slirp->restricted = restricted;
slirp->in_enabled = in_enabled;
slirp->in6_enabled = in6_enabled;
if_init(slirp);
ip_init(slirp);
ip6_init(slirp);
/* Initialise mbufs *after* setting the MTU */
m_init(slirp);
slirp->vnetwork_addr = vnetwork;
slirp->vnetwork_mask = vnetmask;
slirp->vhost_addr = vhost;
slirp->vprefix_addr6 = vprefix_addr6;
slirp->vprefix_len = vprefix_len;
slirp->vhost_addr6 = vhost6;
if (vhostname) {
pstrcpy(slirp->client_hostname, sizeof(slirp->client_hostname),
vhostname);
}
slirp->tftp_prefix = g_strdup(tftp_path);
slirp->bootp_filename = g_strdup(bootfile);
slirp->vdomainname = g_strdup(vdomainname);
slirp->vdhcp_startaddr = vdhcp_start;
slirp->vnameserver_addr = vnameserver;
slirp->vnameserver_addr6 = vnameserver6;
if (vdnssearch) {
translate_dnssearch(slirp, vdnssearch);
}
slirp->opaque = opaque;
register_savevm_live(NULL, "slirp", 0, 4, &savevm_slirp_state, slirp);
QTAILQ_INSERT_TAIL(&slirp_instances, slirp, entry);
return slirp;
}
void slirp_cleanup(Slirp *slirp)
{
QTAILQ_REMOVE(&slirp_instances, slirp, entry);
unregister_savevm(NULL, "slirp", slirp);
ip_cleanup(slirp);
ip6_cleanup(slirp);
m_cleanup(slirp);
g_rand_free(slirp->grand);
g_free(slirp->vdnssearch);
g_free(slirp->tftp_prefix);
g_free(slirp->bootp_filename);
g_free(slirp->vdomainname);
g_free(slirp);
}
#define CONN_CANFSEND(so) (((so)->so_state & (SS_FCANTSENDMORE|SS_ISFCONNECTED)) == SS_ISFCONNECTED)
#define CONN_CANFRCV(so) (((so)->so_state & (SS_FCANTRCVMORE|SS_ISFCONNECTED)) == SS_ISFCONNECTED)
static void slirp_update_timeout(uint32_t *timeout)
{
Slirp *slirp;
uint32_t t;
if (*timeout <= TIMEOUT_FAST) {
return;
}
t = MIN(1000, *timeout);
/* If we have tcp timeout with slirp, then we will fill @timeout with
* more precise value.
*/
QTAILQ_FOREACH(slirp, &slirp_instances, entry) {
if (slirp->time_fasttimo) {
*timeout = TIMEOUT_FAST;
return;
}
if (slirp->do_slowtimo) {
t = MIN(TIMEOUT_SLOW, t);
}
}
*timeout = t;
}
void slirp_pollfds_fill(GArray *pollfds, uint32_t *timeout)
{
Slirp *slirp;
struct socket *so, *so_next;
if (QTAILQ_EMPTY(&slirp_instances)) {
return;
}
/*
* First, TCP sockets
*/
QTAILQ_FOREACH(slirp, &slirp_instances, entry) {
/*
* *_slowtimo needs calling if there are IP fragments
* in the fragment queue, or there are TCP connections active
*/
slirp->do_slowtimo = ((slirp->tcb.so_next != &slirp->tcb) ||
(&slirp->ipq.ip_link != slirp->ipq.ip_link.next));
for (so = slirp->tcb.so_next; so != &slirp->tcb;
so = so_next) {
int events = 0;
so_next = so->so_next;
so->pollfds_idx = -1;
/*
* See if we need a tcp_fasttimo
*/
if (slirp->time_fasttimo == 0 &&
so->so_tcpcb->t_flags & TF_DELACK) {
slirp->time_fasttimo = curtime; /* Flag when want a fasttimo */
}
/*
* NOFDREF can include still connecting to local-host,
* newly socreated() sockets etc. Don't want to select these.
*/
if (so->so_state & SS_NOFDREF || so->s == -1) {
continue;
}
/*
* Set for reading sockets which are accepting
*/
if (so->so_state & SS_FACCEPTCONN) {
GPollFD pfd = {
.fd = so->s,
.events = G_IO_IN | G_IO_HUP | G_IO_ERR,
};
so->pollfds_idx = pollfds->len;
g_array_append_val(pollfds, pfd);
continue;
}
/*
* Set for writing sockets which are connecting
*/
if (so->so_state & SS_ISFCONNECTING) {
GPollFD pfd = {
.fd = so->s,
.events = G_IO_OUT | G_IO_ERR,
};
so->pollfds_idx = pollfds->len;
g_array_append_val(pollfds, pfd);
continue;
}
/*
* Set for writing if we are connected, can send more, and
* we have something to send
*/
if (CONN_CANFSEND(so) && so->so_rcv.sb_cc) {
events |= G_IO_OUT | G_IO_ERR;
}
/*
* Set for reading (and urgent data) if we are connected, can
* receive more, and we have room for it XXX /2 ?
*/
if (CONN_CANFRCV(so) &&
(so->so_snd.sb_cc < (so->so_snd.sb_datalen/2))) {
events |= G_IO_IN | G_IO_HUP | G_IO_ERR | G_IO_PRI;
}
if (events) {
GPollFD pfd = {
.fd = so->s,
.events = events,
};
so->pollfds_idx = pollfds->len;
g_array_append_val(pollfds, pfd);
}
}
/*
* UDP sockets
*/
for (so = slirp->udb.so_next; so != &slirp->udb;
so = so_next) {
so_next = so->so_next;
so->pollfds_idx = -1;
/*
* See if it's timed out
*/
if (so->so_expire) {
if (so->so_expire <= curtime) {
udp_detach(so);
continue;
} else {
slirp->do_slowtimo = true; /* Let socket expire */
}
}
/*
* When UDP packets are received from over the
* link, they're sendto()'d straight away, so
* no need for setting for writing
* Limit the number of packets queued by this session
* to 4. Note that even though we try and limit this
* to 4 packets, the session could have more queued
* if the packets needed to be fragmented
* (XXX <= 4 ?)
*/
if ((so->so_state & SS_ISFCONNECTED) && so->so_queued <= 4) {
GPollFD pfd = {
.fd = so->s,
.events = G_IO_IN | G_IO_HUP | G_IO_ERR,
};
so->pollfds_idx = pollfds->len;
g_array_append_val(pollfds, pfd);
}
}
/*
* ICMP sockets
*/
for (so = slirp->icmp.so_next; so != &slirp->icmp;
so = so_next) {
so_next = so->so_next;
so->pollfds_idx = -1;
/*
* See if it's timed out
*/
if (so->so_expire) {
if (so->so_expire <= curtime) {
icmp_detach(so);
continue;
} else {
slirp->do_slowtimo = true; /* Let socket expire */
}
}
if (so->so_state & SS_ISFCONNECTED) {
GPollFD pfd = {
.fd = so->s,
.events = G_IO_IN | G_IO_HUP | G_IO_ERR,
};
so->pollfds_idx = pollfds->len;
g_array_append_val(pollfds, pfd);
}
}
}
slirp_update_timeout(timeout);
}
void slirp_pollfds_poll(GArray *pollfds, int select_error)
{
Slirp *slirp;
struct socket *so, *so_next;
int ret;
if (QTAILQ_EMPTY(&slirp_instances)) {
return;
}
curtime = qemu_clock_get_ms(QEMU_CLOCK_REALTIME);
QTAILQ_FOREACH(slirp, &slirp_instances, entry) {
/*
* See if anything has timed out
*/
if (slirp->time_fasttimo &&
((curtime - slirp->time_fasttimo) >= TIMEOUT_FAST)) {
tcp_fasttimo(slirp);
slirp->time_fasttimo = 0;
}
if (slirp->do_slowtimo &&
((curtime - slirp->last_slowtimo) >= TIMEOUT_SLOW)) {
ip_slowtimo(slirp);
tcp_slowtimo(slirp);
slirp->last_slowtimo = curtime;
}
/*
* Check sockets
*/
if (!select_error) {
/*
* Check TCP sockets
*/
for (so = slirp->tcb.so_next; so != &slirp->tcb;
so = so_next) {
int revents;
so_next = so->so_next;
revents = 0;
if (so->pollfds_idx != -1) {
revents = g_array_index(pollfds, GPollFD,
so->pollfds_idx).revents;
}
if (so->so_state & SS_NOFDREF || so->s == -1) {
continue;
}
/*
* Check for URG data
* This will soread as well, so no need to
* test for G_IO_IN below if this succeeds
*/
if (revents & G_IO_PRI) {
ret = sorecvoob(so);
if (ret < 0) {
/* Socket error might have resulted in the socket being
* removed, do not try to do anything more with it. */
continue;
}
}
/*
* Check sockets for reading
*/
else if (revents & (G_IO_IN | G_IO_HUP | G_IO_ERR)) {
/*
* Check for incoming connections
*/
if (so->so_state & SS_FACCEPTCONN) {
tcp_connect(so);
continue;
} /* else */
ret = soread(so);
/* Output it if we read something */
if (ret > 0) {
tcp_output(sototcpcb(so));
}
if (ret < 0) {
/* Socket error might have resulted in the socket being
* removed, do not try to do anything more with it. */
continue;
}
}
/*
* Check sockets for writing
*/
if (!(so->so_state & SS_NOFDREF) &&
(revents & (G_IO_OUT | G_IO_ERR))) {
/*
* Check for non-blocking, still-connecting sockets
*/
if (so->so_state & SS_ISFCONNECTING) {
/* Connected */
so->so_state &= ~SS_ISFCONNECTING;
ret = send(so->s, (const void *) &ret, 0, 0);
if (ret < 0) {
/* XXXXX Must fix, zero bytes is a NOP */
if (errno == EAGAIN || errno == EWOULDBLOCK ||
errno == EINPROGRESS || errno == ENOTCONN) {
continue;
}
/* else failed */
so->so_state &= SS_PERSISTENT_MASK;
so->so_state |= SS_NOFDREF;
}
/* else so->so_state &= ~SS_ISFCONNECTING; */
/*
* Continue tcp_input
*/
tcp_input((struct mbuf *)NULL, sizeof(struct ip), so,
so->so_ffamily);
/* continue; */
} else {
ret = sowrite(so);
if (ret > 0) {
/* Call tcp_output in case we need to send a window
* update to the guest, otherwise it will be stuck
* until it sends a window probe. */
tcp_output(sototcpcb(so));
}
}
}
/*
* Probe a still-connecting, non-blocking socket
* to check if it's still alive
*/
#ifdef PROBE_CONN
if (so->so_state & SS_ISFCONNECTING) {
ret = qemu_recv(so->s, &ret, 0, 0);
if (ret < 0) {
/* XXX */
if (errno == EAGAIN || errno == EWOULDBLOCK ||
errno == EINPROGRESS || errno == ENOTCONN) {
continue; /* Still connecting, continue */
}
/* else failed */
so->so_state &= SS_PERSISTENT_MASK;
so->so_state |= SS_NOFDREF;
/* tcp_input will take care of it */
} else {
ret = send(so->s, &ret, 0, 0);
if (ret < 0) {
/* XXX */
if (errno == EAGAIN || errno == EWOULDBLOCK ||
errno == EINPROGRESS || errno == ENOTCONN) {
continue;
}
/* else failed */
so->so_state &= SS_PERSISTENT_MASK;
so->so_state |= SS_NOFDREF;
} else {
so->so_state &= ~SS_ISFCONNECTING;
}
}
tcp_input((struct mbuf *)NULL, sizeof(struct ip), so,
so->so_ffamily);
} /* SS_ISFCONNECTING */
#endif
}
/*
* Now UDP sockets.
* Incoming packets are sent straight away, they're not buffered.
* Incoming UDP data isn't buffered either.
*/
for (so = slirp->udb.so_next; so != &slirp->udb;
so = so_next) {
int revents;
so_next = so->so_next;
revents = 0;
if (so->pollfds_idx != -1) {
revents = g_array_index(pollfds, GPollFD,
so->pollfds_idx).revents;
}
if (so->s != -1 &&
(revents & (G_IO_IN | G_IO_HUP | G_IO_ERR))) {
sorecvfrom(so);
}
}
/*
* Check incoming ICMP relies.
*/
for (so = slirp->icmp.so_next; so != &slirp->icmp;
so = so_next) {
int revents;
so_next = so->so_next;
revents = 0;
if (so->pollfds_idx != -1) {
revents = g_array_index(pollfds, GPollFD,
so->pollfds_idx).revents;
}
if (so->s != -1 &&
(revents & (G_IO_IN | G_IO_HUP | G_IO_ERR))) {
icmp_receive(so);
}
}
}
if_start(slirp);
}
}
static void arp_input(Slirp *slirp, const uint8_t *pkt, int pkt_len)
{
struct slirp_arphdr *ah = (struct slirp_arphdr *)(pkt + ETH_HLEN);
uint8_t arp_reply[MAX(ETH_HLEN + sizeof(struct slirp_arphdr), 64)];
struct ethhdr *reh = (struct ethhdr *)arp_reply;
struct slirp_arphdr *rah = (struct slirp_arphdr *)(arp_reply + ETH_HLEN);
int ar_op;
struct ex_list *ex_ptr;
if (!slirp->in_enabled) {
return;
}
ar_op = ntohs(ah->ar_op);
switch(ar_op) {
case ARPOP_REQUEST:
if (ah->ar_tip == ah->ar_sip) {
/* Gratuitous ARP */
arp_table_add(slirp, ah->ar_sip, ah->ar_sha);
return;
}
if ((ah->ar_tip & slirp->vnetwork_mask.s_addr) ==
slirp->vnetwork_addr.s_addr) {
if (ah->ar_tip == slirp->vnameserver_addr.s_addr ||
ah->ar_tip == slirp->vhost_addr.s_addr)
goto arp_ok;
for (ex_ptr = slirp->exec_list; ex_ptr; ex_ptr = ex_ptr->ex_next) {
if (ex_ptr->ex_addr.s_addr == ah->ar_tip)
goto arp_ok;
}
return;
arp_ok:
memset(arp_reply, 0, sizeof(arp_reply));
arp_table_add(slirp, ah->ar_sip, ah->ar_sha);
/* ARP request for alias/dns mac address */
memcpy(reh->h_dest, pkt + ETH_ALEN, ETH_ALEN);
memcpy(reh->h_source, special_ethaddr, ETH_ALEN - 4);
memcpy(&reh->h_source[2], &ah->ar_tip, 4);
reh->h_proto = htons(ETH_P_ARP);
rah->ar_hrd = htons(1);
rah->ar_pro = htons(ETH_P_IP);
rah->ar_hln = ETH_ALEN;
rah->ar_pln = 4;
rah->ar_op = htons(ARPOP_REPLY);
memcpy(rah->ar_sha, reh->h_source, ETH_ALEN);
rah->ar_sip = ah->ar_tip;
memcpy(rah->ar_tha, ah->ar_sha, ETH_ALEN);
rah->ar_tip = ah->ar_sip;
slirp_output(slirp->opaque, arp_reply, sizeof(arp_reply));
}
break;
case ARPOP_REPLY:
arp_table_add(slirp, ah->ar_sip, ah->ar_sha);
break;
default:
break;
}
}
void slirp_input(Slirp *slirp, const uint8_t *pkt, int pkt_len)
{
struct mbuf *m;
int proto;
if (pkt_len < ETH_HLEN)
return;
proto = ntohs(*(uint16_t *)(pkt + 12));
switch(proto) {
case ETH_P_ARP:
arp_input(slirp, pkt, pkt_len);
break;
case ETH_P_IP:
case ETH_P_IPV6:
m = m_get(slirp);
if (!m)
return;
/* Note: we add 2 to align the IP header on 4 bytes,
* and add the margin for the tcpiphdr overhead */
if (M_FREEROOM(m) < pkt_len + TCPIPHDR_DELTA + 2) {
m_inc(m, pkt_len + TCPIPHDR_DELTA + 2);
}
m->m_len = pkt_len + TCPIPHDR_DELTA + 2;
memcpy(m->m_data + TCPIPHDR_DELTA + 2, pkt, pkt_len);
m->m_data += TCPIPHDR_DELTA + 2 + ETH_HLEN;
m->m_len -= TCPIPHDR_DELTA + 2 + ETH_HLEN;
if (proto == ETH_P_IP) {
ip_input(m);
} else if (proto == ETH_P_IPV6) {
ip6_input(m);
}
break;
case ETH_P_NCSI:
ncsi_input(slirp, pkt, pkt_len);
break;
default:
break;
}
}
/* Prepare the IPv4 packet to be sent to the ethernet device. Returns 1 if no
* packet should be sent, 0 if the packet must be re-queued, 2 if the packet
* is ready to go.
*/
static int if_encap4(Slirp *slirp, struct mbuf *ifm, struct ethhdr *eh,
uint8_t ethaddr[ETH_ALEN])
{
const struct ip *iph = (const struct ip *)ifm->m_data;
if (iph->ip_dst.s_addr == 0) {
/* 0.0.0.0 can not be a destination address, something went wrong,
* avoid making it worse */
return 1;
}
if (!arp_table_search(slirp, iph->ip_dst.s_addr, ethaddr)) {
uint8_t arp_req[ETH_HLEN + sizeof(struct slirp_arphdr)];
struct ethhdr *reh = (struct ethhdr *)arp_req;
struct slirp_arphdr *rah = (struct slirp_arphdr *)(arp_req + ETH_HLEN);
if (!ifm->resolution_requested) {
/* If the client addr is not known, send an ARP request */
memset(reh->h_dest, 0xff, ETH_ALEN);
memcpy(reh->h_source, special_ethaddr, ETH_ALEN - 4);
memcpy(&reh->h_source[2], &slirp->vhost_addr, 4);
reh->h_proto = htons(ETH_P_ARP);
rah->ar_hrd = htons(1);
rah->ar_pro = htons(ETH_P_IP);
rah->ar_hln = ETH_ALEN;
rah->ar_pln = 4;
rah->ar_op = htons(ARPOP_REQUEST);
/* source hw addr */
memcpy(rah->ar_sha, special_ethaddr, ETH_ALEN - 4);
memcpy(&rah->ar_sha[2], &slirp->vhost_addr, 4);
/* source IP */
rah->ar_sip = slirp->vhost_addr.s_addr;
/* target hw addr (none) */
memset(rah->ar_tha, 0, ETH_ALEN);
/* target IP */
rah->ar_tip = iph->ip_dst.s_addr;
slirp->client_ipaddr = iph->ip_dst;
slirp_output(slirp->opaque, arp_req, sizeof(arp_req));
ifm->resolution_requested = true;
/* Expire request and drop outgoing packet after 1 second */
ifm->expiration_date = qemu_clock_get_ns(QEMU_CLOCK_REALTIME) + 1000000000ULL;
}
return 0;
} else {
memcpy(eh->h_source, special_ethaddr, ETH_ALEN - 4);
/* XXX: not correct */
memcpy(&eh->h_source[2], &slirp->vhost_addr, 4);
eh->h_proto = htons(ETH_P_IP);
/* Send this */
return 2;
}
}
/* Prepare the IPv6 packet to be sent to the ethernet device. Returns 1 if no
* packet should be sent, 0 if the packet must be re-queued, 2 if the packet
* is ready to go.
*/
static int if_encap6(Slirp *slirp, struct mbuf *ifm, struct ethhdr *eh,
uint8_t ethaddr[ETH_ALEN])
{
const struct ip6 *ip6h = mtod(ifm, const struct ip6 *);
if (!ndp_table_search(slirp, ip6h->ip_dst, ethaddr)) {
if (!ifm->resolution_requested) {
ndp_send_ns(slirp, ip6h->ip_dst);
ifm->resolution_requested = true;
ifm->expiration_date =
qemu_clock_get_ns(QEMU_CLOCK_REALTIME) + 1000000000ULL;
}
return 0;
} else {
eh->h_proto = htons(ETH_P_IPV6);
in6_compute_ethaddr(ip6h->ip_src, eh->h_source);
/* Send this */
return 2;
}
}
/* Output the IP packet to the ethernet device. Returns 0 if the packet must be
* re-queued.
*/
int if_encap(Slirp *slirp, struct mbuf *ifm)
{
uint8_t buf[1600];
struct ethhdr *eh = (struct ethhdr *)buf;
uint8_t ethaddr[ETH_ALEN];
const struct ip *iph = (const struct ip *)ifm->m_data;
int ret;
if (ifm->m_len + ETH_HLEN > sizeof(buf)) {
return 1;
}
switch (iph->ip_v) {
case IPVERSION:
ret = if_encap4(slirp, ifm, eh, ethaddr);
if (ret < 2) {
return ret;
}
break;
case IP6VERSION:
ret = if_encap6(slirp, ifm, eh, ethaddr);
if (ret < 2) {
return ret;
}
break;
default:
g_assert_not_reached();
break;
}
memcpy(eh->h_dest, ethaddr, ETH_ALEN);
DEBUG_ARGS((dfd, " src = %02x:%02x:%02x:%02x:%02x:%02x\n",
eh->h_source[0], eh->h_source[1], eh->h_source[2],
eh->h_source[3], eh->h_source[4], eh->h_source[5]));
DEBUG_ARGS((dfd, " dst = %02x:%02x:%02x:%02x:%02x:%02x\n",
eh->h_dest[0], eh->h_dest[1], eh->h_dest[2],
eh->h_dest[3], eh->h_dest[4], eh->h_dest[5]));
memcpy(buf + sizeof(struct ethhdr), ifm->m_data, ifm->m_len);
slirp_output(slirp->opaque, buf, ifm->m_len + ETH_HLEN);
return 1;
}
/* Drop host forwarding rule, return 0 if found. */
int slirp_remove_hostfwd(Slirp *slirp, int is_udp, struct in_addr host_addr,
int host_port)
{
struct socket *so;
struct socket *head = (is_udp ? &slirp->udb : &slirp->tcb);
struct sockaddr_in addr;
int port = htons(host_port);
socklen_t addr_len;
for (so = head->so_next; so != head; so = so->so_next) {
addr_len = sizeof(addr);
if ((so->so_state & SS_HOSTFWD) &&
getsockname(so->s, (struct sockaddr *)&addr, &addr_len) == 0 &&
addr.sin_addr.s_addr == host_addr.s_addr &&
addr.sin_port == port) {
close(so->s);
sofree(so);
return 0;
}
}
return -1;
}
int slirp_add_hostfwd(Slirp *slirp, int is_udp, struct in_addr host_addr,
int host_port, struct in_addr guest_addr, int guest_port)
{
if (!guest_addr.s_addr) {
guest_addr = slirp->vdhcp_startaddr;
}
if (is_udp) {
if (!udp_listen(slirp, host_addr.s_addr, htons(host_port),
guest_addr.s_addr, htons(guest_port), SS_HOSTFWD))
return -1;
} else {
if (!tcp_listen(slirp, host_addr.s_addr, htons(host_port),
guest_addr.s_addr, htons(guest_port), SS_HOSTFWD))
return -1;
}
return 0;
}
int slirp_add_exec(Slirp *slirp, int do_pty, const void *args,
struct in_addr *guest_addr, int guest_port)
{
if (!guest_addr->s_addr) {
guest_addr->s_addr = slirp->vnetwork_addr.s_addr |
(htonl(0x0204) & ~slirp->vnetwork_mask.s_addr);
}
if ((guest_addr->s_addr & slirp->vnetwork_mask.s_addr) !=
slirp->vnetwork_addr.s_addr ||
guest_addr->s_addr == slirp->vhost_addr.s_addr ||
guest_addr->s_addr == slirp->vnameserver_addr.s_addr) {
return -1;
}
return add_exec(&slirp->exec_list, do_pty, (char *)args, *guest_addr,
htons(guest_port));
}
ssize_t slirp_send(struct socket *so, const void *buf, size_t len, int flags)
{
if (so->s == -1 && so->extra) {
/* XXX this blocks entire thread. Rewrite to use
* qemu_chr_fe_write and background I/O callbacks */
qemu_chr_fe_write_all(so->extra, buf, len);
return len;
}
return send(so->s, buf, len, flags);
}
static struct socket *
slirp_find_ctl_socket(Slirp *slirp, struct in_addr guest_addr, int guest_port)
{
struct socket *so;
for (so = slirp->tcb.so_next; so != &slirp->tcb; so = so->so_next) {
if (so->so_faddr.s_addr == guest_addr.s_addr &&
htons(so->so_fport) == guest_port) {
return so;
}
}
return NULL;
}
size_t slirp_socket_can_recv(Slirp *slirp, struct in_addr guest_addr,
int guest_port)
{
struct iovec iov[2];
struct socket *so;
so = slirp_find_ctl_socket(slirp, guest_addr, guest_port);
if (!so || so->so_state & SS_NOFDREF) {
return 0;
}
if (!CONN_CANFRCV(so) || so->so_snd.sb_cc >= (so->so_snd.sb_datalen/2)) {
return 0;
}
return sopreprbuf(so, iov, NULL);
}
void slirp_socket_recv(Slirp *slirp, struct in_addr guest_addr, int guest_port,
const uint8_t *buf, int size)
{
int ret;
struct socket *so = slirp_find_ctl_socket(slirp, guest_addr, guest_port);
if (!so)
return;
ret = soreadbuf(so, (const char *)buf, size);
if (ret > 0)
tcp_output(sototcpcb(so));
}
static int slirp_tcp_post_load(void *opaque, int version)
{
tcp_template((struct tcpcb *)opaque);
return 0;
}
static const VMStateDescription vmstate_slirp_tcp = {
.name = "slirp-tcp",
.version_id = 0,
.post_load = slirp_tcp_post_load,
.fields = (VMStateField[]) {
VMSTATE_INT16(t_state, struct tcpcb),
VMSTATE_INT16_ARRAY(t_timer, struct tcpcb, TCPT_NTIMERS),
VMSTATE_INT16(t_rxtshift, struct tcpcb),
VMSTATE_INT16(t_rxtcur, struct tcpcb),
VMSTATE_INT16(t_dupacks, struct tcpcb),
VMSTATE_UINT16(t_maxseg, struct tcpcb),
VMSTATE_UINT8(t_force, struct tcpcb),
VMSTATE_UINT16(t_flags, struct tcpcb),
VMSTATE_UINT32(snd_una, struct tcpcb),
VMSTATE_UINT32(snd_nxt, struct tcpcb),
VMSTATE_UINT32(snd_up, struct tcpcb),
VMSTATE_UINT32(snd_wl1, struct tcpcb),
VMSTATE_UINT32(snd_wl2, struct tcpcb),
VMSTATE_UINT32(iss, struct tcpcb),
VMSTATE_UINT32(snd_wnd, struct tcpcb),
VMSTATE_UINT32(rcv_wnd, struct tcpcb),
VMSTATE_UINT32(rcv_nxt, struct tcpcb),
VMSTATE_UINT32(rcv_up, struct tcpcb),
VMSTATE_UINT32(irs, struct tcpcb),
VMSTATE_UINT32(rcv_adv, struct tcpcb),
VMSTATE_UINT32(snd_max, struct tcpcb),
VMSTATE_UINT32(snd_cwnd, struct tcpcb),
VMSTATE_UINT32(snd_ssthresh, struct tcpcb),
VMSTATE_INT16(t_idle, struct tcpcb),
VMSTATE_INT16(t_rtt, struct tcpcb),
VMSTATE_UINT32(t_rtseq, struct tcpcb),
VMSTATE_INT16(t_srtt, struct tcpcb),
VMSTATE_INT16(t_rttvar, struct tcpcb),
VMSTATE_UINT16(t_rttmin, struct tcpcb),
VMSTATE_UINT32(max_sndwnd, struct tcpcb),
VMSTATE_UINT8(t_oobflags, struct tcpcb),
VMSTATE_UINT8(t_iobc, struct tcpcb),
VMSTATE_INT16(t_softerror, struct tcpcb),
VMSTATE_UINT8(snd_scale, struct tcpcb),
VMSTATE_UINT8(rcv_scale, struct tcpcb),
VMSTATE_UINT8(request_r_scale, struct tcpcb),
VMSTATE_UINT8(requested_s_scale, struct tcpcb),
VMSTATE_UINT32(ts_recent, struct tcpcb),
VMSTATE_UINT32(ts_recent_age, struct tcpcb),
VMSTATE_UINT32(last_ack_sent, struct tcpcb),
VMSTATE_END_OF_LIST()
}
};
/* The sbuf has a pair of pointers that are migrated as offsets;
* we calculate the offsets and restore the pointers using
* pre_save/post_load on a tmp structure.
*/
struct sbuf_tmp {
struct sbuf *parent;
uint32_t roff, woff;
};
static int sbuf_tmp_pre_save(void *opaque)
{
struct sbuf_tmp *tmp = opaque;
tmp->woff = tmp->parent->sb_wptr - tmp->parent->sb_data;
tmp->roff = tmp->parent->sb_rptr - tmp->parent->sb_data;
return 0;
}
static int sbuf_tmp_post_load(void *opaque, int version)
{
struct sbuf_tmp *tmp = opaque;
uint32_t requested_len = tmp->parent->sb_datalen;
/* Allocate the buffer space used by the field after the tmp */
sbreserve(tmp->parent, tmp->parent->sb_datalen);
if (tmp->parent->sb_datalen != requested_len) {
return -ENOMEM;
}
if (tmp->woff >= requested_len ||
tmp->roff >= requested_len) {
error_report("invalid sbuf offsets r/w=%u/%u len=%u",
tmp->roff, tmp->woff, requested_len);
return -EINVAL;
}
tmp->parent->sb_wptr = tmp->parent->sb_data + tmp->woff;
tmp->parent->sb_rptr = tmp->parent->sb_data + tmp->roff;
return 0;
}
static const VMStateDescription vmstate_slirp_sbuf_tmp = {
.name = "slirp-sbuf-tmp",
.post_load = sbuf_tmp_post_load,
.pre_save = sbuf_tmp_pre_save,
.version_id = 0,
.fields = (VMStateField[]) {
VMSTATE_UINT32(woff, struct sbuf_tmp),
VMSTATE_UINT32(roff, struct sbuf_tmp),
VMSTATE_END_OF_LIST()
}
};
static const VMStateDescription vmstate_slirp_sbuf = {
.name = "slirp-sbuf",
.version_id = 0,
.fields = (VMStateField[]) {
VMSTATE_UINT32(sb_cc, struct sbuf),
VMSTATE_UINT32(sb_datalen, struct sbuf),
VMSTATE_WITH_TMP(struct sbuf, struct sbuf_tmp, vmstate_slirp_sbuf_tmp),
VMSTATE_VBUFFER_UINT32(sb_data, struct sbuf, 0, NULL, sb_datalen),
VMSTATE_END_OF_LIST()
}
};
static bool slirp_older_than_v4(void *opaque, int version_id)
{
return version_id < 4;
}
static bool slirp_family_inet(void *opaque, int version_id)
{
union slirp_sockaddr *ssa = (union slirp_sockaddr *)opaque;
return ssa->ss.ss_family == AF_INET;
}
static int slirp_socket_pre_load(void *opaque)
{
struct socket *so = opaque;
if (tcp_attach(so) < 0) {
return -ENOMEM;
}
/* Older versions don't load these fields */
so->so_ffamily = AF_INET;
so->so_lfamily = AF_INET;
return 0;
}
#ifndef _WIN32
#define VMSTATE_SIN4_ADDR(f, s, t) VMSTATE_UINT32_TEST(f, s, t)
#else
/* Win uses u_long rather than uint32_t - but it's still 32bits long */
#define VMSTATE_SIN4_ADDR(f, s, t) VMSTATE_SINGLE_TEST(f, s, t, 0, \
vmstate_info_uint32, u_long)
#endif
/* The OS provided ss_family field isn't that portable; it's size
* and type varies (16/8 bit, signed, unsigned)
* and the values it contains aren't fully portable.
*/
typedef struct SS_FamilyTmpStruct {
union slirp_sockaddr *parent;
uint16_t portable_family;
} SS_FamilyTmpStruct;
#define SS_FAMILY_MIG_IPV4 2 /* Linux, BSD, Win... */
#define SS_FAMILY_MIG_IPV6 10 /* Linux */
#define SS_FAMILY_MIG_OTHER 0xffff
static int ss_family_pre_save(void *opaque)
{
SS_FamilyTmpStruct *tss = opaque;
tss->portable_family = SS_FAMILY_MIG_OTHER;
if (tss->parent->ss.ss_family == AF_INET) {
tss->portable_family = SS_FAMILY_MIG_IPV4;
} else if (tss->parent->ss.ss_family == AF_INET6) {
tss->portable_family = SS_FAMILY_MIG_IPV6;
}
return 0;
}
static int ss_family_post_load(void *opaque, int version_id)
{
SS_FamilyTmpStruct *tss = opaque;
switch (tss->portable_family) {
case SS_FAMILY_MIG_IPV4:
tss->parent->ss.ss_family = AF_INET;
break;
case SS_FAMILY_MIG_IPV6:
case 23: /* compatibility: AF_INET6 from mingw */
case 28: /* compatibility: AF_INET6 from FreeBSD sys/socket.h */
tss->parent->ss.ss_family = AF_INET6;
break;
default:
error_report("invalid ss_family type %x", tss->portable_family);
return -EINVAL;
}
return 0;
}
static const VMStateDescription vmstate_slirp_ss_family = {
.name = "slirp-socket-addr/ss_family",
.pre_save = ss_family_pre_save,
.post_load = ss_family_post_load,
.fields = (VMStateField[]) {
VMSTATE_UINT16(portable_family, SS_FamilyTmpStruct),
VMSTATE_END_OF_LIST()
}
};
static const VMStateDescription vmstate_slirp_socket_addr = {
.name = "slirp-socket-addr",
.version_id = 4,
.fields = (VMStateField[]) {
VMSTATE_WITH_TMP(union slirp_sockaddr, SS_FamilyTmpStruct,
vmstate_slirp_ss_family),
VMSTATE_SIN4_ADDR(sin.sin_addr.s_addr, union slirp_sockaddr,
slirp_family_inet),
VMSTATE_UINT16_TEST(sin.sin_port, union slirp_sockaddr,
slirp_family_inet),
#if 0
/* Untested: Needs checking by someone with IPv6 test */
VMSTATE_BUFFER_TEST(sin6.sin6_addr, union slirp_sockaddr,
slirp_family_inet6),
VMSTATE_UINT16_TEST(sin6.sin6_port, union slirp_sockaddr,
slirp_family_inet6),
VMSTATE_UINT32_TEST(sin6.sin6_flowinfo, union slirp_sockaddr,
slirp_family_inet6),
VMSTATE_UINT32_TEST(sin6.sin6_scope_id, union slirp_sockaddr,
slirp_family_inet6),
#endif
VMSTATE_END_OF_LIST()
}
};
static const VMStateDescription vmstate_slirp_socket = {
.name = "slirp-socket",
.version_id = 4,
.pre_load = slirp_socket_pre_load,
.fields = (VMStateField[]) {
VMSTATE_UINT32(so_urgc, struct socket),
/* Pre-v4 versions */
VMSTATE_SIN4_ADDR(so_faddr.s_addr, struct socket,
slirp_older_than_v4),
VMSTATE_SIN4_ADDR(so_laddr.s_addr, struct socket,
slirp_older_than_v4),
VMSTATE_UINT16_TEST(so_fport, struct socket, slirp_older_than_v4),
VMSTATE_UINT16_TEST(so_lport, struct socket, slirp_older_than_v4),
/* v4 and newer */
VMSTATE_STRUCT(fhost, struct socket, 4, vmstate_slirp_socket_addr,
union slirp_sockaddr),
VMSTATE_STRUCT(lhost, struct socket, 4, vmstate_slirp_socket_addr,
union slirp_sockaddr),
VMSTATE_UINT8(so_iptos, struct socket),
VMSTATE_UINT8(so_emu, struct socket),
VMSTATE_UINT8(so_type, struct socket),
VMSTATE_INT32(so_state, struct socket),
VMSTATE_STRUCT(so_rcv, struct socket, 0, vmstate_slirp_sbuf,
struct sbuf),
VMSTATE_STRUCT(so_snd, struct socket, 0, vmstate_slirp_sbuf,
struct sbuf),
VMSTATE_STRUCT_POINTER(so_tcpcb, struct socket, vmstate_slirp_tcp,
struct tcpcb),
VMSTATE_END_OF_LIST()
}
};
static const VMStateDescription vmstate_slirp_bootp_client = {
.name = "slirp_bootpclient",
.fields = (VMStateField[]) {
VMSTATE_UINT16(allocated, BOOTPClient),
VMSTATE_BUFFER(macaddr, BOOTPClient),
VMSTATE_END_OF_LIST()
}
};
static const VMStateDescription vmstate_slirp = {
.name = "slirp",
.version_id = 4,
.fields = (VMStateField[]) {
VMSTATE_UINT16_V(ip_id, Slirp, 2),
VMSTATE_STRUCT_ARRAY(bootp_clients, Slirp, NB_BOOTP_CLIENTS, 3,
vmstate_slirp_bootp_client, BOOTPClient),
VMSTATE_END_OF_LIST()
}
};
static void slirp_state_save(QEMUFile *f, void *opaque)
{
Slirp *slirp = opaque;
struct ex_list *ex_ptr;
for (ex_ptr = slirp->exec_list; ex_ptr; ex_ptr = ex_ptr->ex_next)
if (ex_ptr->ex_pty == 3) {
struct socket *so;
so = slirp_find_ctl_socket(slirp, ex_ptr->ex_addr,
ntohs(ex_ptr->ex_fport));
if (!so)
continue;
qemu_put_byte(f, 42);
vmstate_save_state(f, &vmstate_slirp_socket, so, NULL);
}
qemu_put_byte(f, 0);
vmstate_save_state(f, &vmstate_slirp, slirp, NULL);
}
static int slirp_state_load(QEMUFile *f, void *opaque, int version_id)
{
Slirp *slirp = opaque;
struct ex_list *ex_ptr;
while (qemu_get_byte(f)) {
int ret;
struct socket *so = socreate(slirp);
if (!so)
return -ENOMEM;
ret = vmstate_load_state(f, &vmstate_slirp_socket, so, version_id);
if (ret < 0)
return ret;
if ((so->so_faddr.s_addr & slirp->vnetwork_mask.s_addr) !=
slirp->vnetwork_addr.s_addr) {
return -EINVAL;
}
for (ex_ptr = slirp->exec_list; ex_ptr; ex_ptr = ex_ptr->ex_next) {
if (ex_ptr->ex_pty == 3 &&
so->so_faddr.s_addr == ex_ptr->ex_addr.s_addr &&
so->so_fport == ex_ptr->ex_fport) {
break;
}
}
if (!ex_ptr)
return -EINVAL;
so->extra = (void *)ex_ptr->ex_exec;
}
return vmstate_load_state(f, &vmstate_slirp, slirp, version_id);
}