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|
/* SPDX-License-Identifier: BSD-3-Clause */
/*
* Copyright (c) 1995 Danny Gasparovski.
*/
#include "slirp.h"
#include "ip_icmp.h"
#ifdef __sun__
#include <sys/filio.h>
#endif
#ifdef __linux__
#include <linux/errqueue.h>
#endif
static void sofcantrcvmore(struct socket *so);
static void sofcantsendmore(struct socket *so);
struct socket *solookup(struct socket **last, struct socket *head,
struct sockaddr_storage *lhost,
struct sockaddr_storage *fhost)
{
struct socket *so = *last;
/* Optimisation */
if (so != head && sockaddr_equal(&(so->lhost.ss), lhost) &&
(!fhost || sockaddr_equal(&so->fhost.ss, fhost))) {
return so;
}
for (so = head->so_next; so != head; so = so->so_next) {
if (sockaddr_equal(&(so->lhost.ss), lhost) &&
(!fhost || sockaddr_equal(&so->fhost.ss, fhost))) {
*last = so;
return so;
}
}
return (struct socket *)NULL;
}
/*
* Create a new socket, initialise the fields
* It is the responsibility of the caller to
* insque() it into the correct linked-list
*/
struct socket *socreate(Slirp *slirp, int type)
{
struct socket *so = g_new(struct socket, 1);
memset(so, 0, sizeof(struct socket));
so->so_type = type;
so->so_state = SS_NOFDREF;
so->s = -1;
so->s_aux = -1;
so->slirp = slirp;
so->pollfds_idx = -1;
return so;
}
/*
* Remove references to so from the given message queue.
*/
static void soqfree(struct socket *so, struct quehead *qh)
{
struct mbuf *ifq;
for (ifq = (struct mbuf *)qh->qh_link; (struct quehead *)ifq != qh;
ifq = ifq->ifq_next) {
if (ifq->ifq_so == so) {
struct mbuf *ifm;
ifq->ifq_so = NULL;
for (ifm = ifq->ifs_next; ifm != ifq; ifm = ifm->ifs_next) {
ifm->ifq_so = NULL;
}
}
}
}
/*
* remque and free a socket, clobber cache
*/
void sofree(struct socket *so)
{
Slirp *slirp = so->slirp;
if (so->s_aux != -1) {
closesocket(so->s_aux);
}
soqfree(so, &slirp->if_fastq);
soqfree(so, &slirp->if_batchq);
if (so == slirp->tcp_last_so) {
slirp->tcp_last_so = &slirp->tcb;
} else if (so == slirp->udp_last_so) {
slirp->udp_last_so = &slirp->udb;
} else if (so == slirp->icmp_last_so) {
slirp->icmp_last_so = &slirp->icmp;
}
m_free(so->so_m);
if (so->so_next && so->so_prev)
remque(so); /* crashes if so is not in a queue */
if (so->so_tcpcb) {
g_free(so->so_tcpcb);
}
g_free(so);
}
size_t sopreprbuf(struct socket *so, struct iovec *iov, int *np)
{
int n, lss, total;
struct sbuf *sb = &so->so_snd;
int len = sb->sb_datalen - sb->sb_cc;
int mss = so->so_tcpcb->t_maxseg;
DEBUG_CALL("sopreprbuf");
DEBUG_ARG("so = %p", so);
if (len <= 0)
return 0;
iov[0].iov_base = sb->sb_wptr;
iov[1].iov_base = NULL;
iov[1].iov_len = 0;
if (sb->sb_wptr < sb->sb_rptr) {
iov[0].iov_len = sb->sb_rptr - sb->sb_wptr;
/* Should never succeed, but... */
if (iov[0].iov_len > len)
iov[0].iov_len = len;
if (iov[0].iov_len > mss)
iov[0].iov_len -= iov[0].iov_len % mss;
n = 1;
} else {
iov[0].iov_len = (sb->sb_data + sb->sb_datalen) - sb->sb_wptr;
/* Should never succeed, but... */
if (iov[0].iov_len > len)
iov[0].iov_len = len;
len -= iov[0].iov_len;
if (len) {
iov[1].iov_base = sb->sb_data;
iov[1].iov_len = sb->sb_rptr - sb->sb_data;
if (iov[1].iov_len > len)
iov[1].iov_len = len;
total = iov[0].iov_len + iov[1].iov_len;
if (total > mss) {
lss = total % mss;
if (iov[1].iov_len > lss) {
iov[1].iov_len -= lss;
n = 2;
} else {
lss -= iov[1].iov_len;
iov[0].iov_len -= lss;
n = 1;
}
} else
n = 2;
} else {
if (iov[0].iov_len > mss)
iov[0].iov_len -= iov[0].iov_len % mss;
n = 1;
}
}
if (np)
*np = n;
return iov[0].iov_len + (n - 1) * iov[1].iov_len;
}
/*
* Read from so's socket into sb_snd, updating all relevant sbuf fields
* NOTE: This will only be called if it is select()ed for reading, so
* a read() of 0 (or less) means it's disconnected
*/
int soread(struct socket *so)
{
int n, nn;
size_t buf_len;
struct sbuf *sb = &so->so_snd;
struct iovec iov[2];
DEBUG_CALL("soread");
DEBUG_ARG("so = %p", so);
/*
* No need to check if there's enough room to read.
* soread wouldn't have been called if there weren't
*/
buf_len = sopreprbuf(so, iov, &n);
assert(buf_len != 0);
nn = recv(so->s, iov[0].iov_base, iov[0].iov_len, 0);
if (nn <= 0) {
if (nn < 0 && (errno == EINTR || errno == EAGAIN))
return 0;
else {
int err;
socklen_t elen = sizeof err;
struct sockaddr_storage addr;
struct sockaddr *paddr = (struct sockaddr *)&addr;
socklen_t alen = sizeof addr;
err = errno;
if (nn == 0) {
int shutdown_wr = so->so_state & SS_FCANTSENDMORE;
if (!shutdown_wr && getpeername(so->s, paddr, &alen) < 0) {
err = errno;
} else {
getsockopt(so->s, SOL_SOCKET, SO_ERROR, &err, &elen);
}
}
DEBUG_MISC(" --- soread() disconnected, nn = %d, errno = %d-%s", nn,
errno, strerror(errno));
sofcantrcvmore(so);
if (err == ECONNRESET || err == ECONNREFUSED || err == ENOTCONN ||
err == EPIPE) {
tcp_drop(sototcpcb(so), err);
} else {
tcp_sockclosed(sototcpcb(so));
}
return -1;
}
}
/*
* If there was no error, try and read the second time round
* We read again if n = 2 (ie, there's another part of the buffer)
* and we read as much as we could in the first read
* We don't test for <= 0 this time, because there legitimately
* might not be any more data (since the socket is non-blocking),
* a close will be detected on next iteration.
* A return of -1 won't (shouldn't) happen, since it didn't happen above
*/
if (n == 2 && nn == iov[0].iov_len) {
int ret;
ret = recv(so->s, iov[1].iov_base, iov[1].iov_len, 0);
if (ret > 0)
nn += ret;
}
DEBUG_MISC(" ... read nn = %d bytes", nn);
/* Update fields */
sb->sb_cc += nn;
sb->sb_wptr += nn;
if (sb->sb_wptr >= (sb->sb_data + sb->sb_datalen))
sb->sb_wptr -= sb->sb_datalen;
return nn;
}
int soreadbuf(struct socket *so, const char *buf, int size)
{
int n, nn, copy = size;
struct sbuf *sb = &so->so_snd;
struct iovec iov[2];
DEBUG_CALL("soreadbuf");
DEBUG_ARG("so = %p", so);
/*
* No need to check if there's enough room to read.
* soread wouldn't have been called if there weren't
*/
assert(size > 0);
if (sopreprbuf(so, iov, &n) < size)
goto err;
nn = MIN(iov[0].iov_len, copy);
memcpy(iov[0].iov_base, buf, nn);
copy -= nn;
buf += nn;
if (copy == 0)
goto done;
memcpy(iov[1].iov_base, buf, copy);
done:
/* Update fields */
sb->sb_cc += size;
sb->sb_wptr += size;
if (sb->sb_wptr >= (sb->sb_data + sb->sb_datalen))
sb->sb_wptr -= sb->sb_datalen;
return size;
err:
sofcantrcvmore(so);
tcp_sockclosed(sototcpcb(so));
g_critical("soreadbuf buffer too small");
return -1;
}
/*
* Get urgent data
*
* When the socket is created, we set it SO_OOBINLINE,
* so when OOB data arrives, we soread() it and everything
* in the send buffer is sent as urgent data
*/
int sorecvoob(struct socket *so)
{
struct tcpcb *tp = sototcpcb(so);
int ret;
DEBUG_CALL("sorecvoob");
DEBUG_ARG("so = %p", so);
/*
* We take a guess at how much urgent data has arrived.
* In most situations, when urgent data arrives, the next
* read() should get all the urgent data. This guess will
* be wrong however if more data arrives just after the
* urgent data, or the read() doesn't return all the
* urgent data.
*/
ret = soread(so);
if (ret > 0) {
tp->snd_up = tp->snd_una + so->so_snd.sb_cc;
tp->t_force = 1;
tcp_output(tp);
tp->t_force = 0;
}
return ret;
}
/*
* Send urgent data
* There's a lot duplicated code here, but...
*/
int sosendoob(struct socket *so)
{
struct sbuf *sb = &so->so_rcv;
char buff[2048]; /* XXX Shouldn't be sending more oob data than this */
int n;
DEBUG_CALL("sosendoob");
DEBUG_ARG("so = %p", so);
DEBUG_ARG("sb->sb_cc = %d", sb->sb_cc);
if (so->so_urgc > sizeof(buff))
so->so_urgc = sizeof(buff); /* XXXX */
if (sb->sb_rptr < sb->sb_wptr) {
/* We can send it directly */
n = slirp_send(so, sb->sb_rptr, so->so_urgc,
(MSG_OOB)); /* |MSG_DONTWAIT)); */
} else {
/*
* Since there's no sendv or sendtov like writev,
* we must copy all data to a linear buffer then
* send it all
*/
uint32_t urgc = so->so_urgc; /* Amount of room left in buff */
int len = (sb->sb_data + sb->sb_datalen) - sb->sb_rptr;
if (len > urgc) {
len = urgc;
}
memcpy(buff, sb->sb_rptr, len);
urgc -= len;
if (urgc) {
/* We still have some room for the rest */
n = sb->sb_wptr - sb->sb_data;
if (n > urgc) {
n = urgc;
}
memcpy((buff + len), sb->sb_data, n);
len += n;
}
n = slirp_send(so, buff, len, (MSG_OOB)); /* |MSG_DONTWAIT)); */
#ifdef DEBUG
if (n != len) {
DEBUG_ERROR("Didn't send all data urgently XXXXX");
}
#endif
}
if (n < 0) {
return n;
}
so->so_urgc -= n;
DEBUG_MISC(" ---2 sent %d bytes urgent data, %d urgent bytes left", n,
so->so_urgc);
sb->sb_cc -= n;
sb->sb_rptr += n;
if (sb->sb_rptr >= (sb->sb_data + sb->sb_datalen))
sb->sb_rptr -= sb->sb_datalen;
return n;
}
/*
* Write data from so_rcv to so's socket,
* updating all sbuf field as necessary
*/
int sowrite(struct socket *so)
{
int n, nn;
struct sbuf *sb = &so->so_rcv;
int len = sb->sb_cc;
struct iovec iov[2];
DEBUG_CALL("sowrite");
DEBUG_ARG("so = %p", so);
if (so->so_urgc) {
uint32_t expected = so->so_urgc;
if (sosendoob(so) < expected) {
/* Treat a short write as a fatal error too,
* rather than continuing on and sending the urgent
* data as if it were non-urgent and leaving the
* so_urgc count wrong.
*/
goto err_disconnected;
}
if (sb->sb_cc == 0)
return 0;
}
/*
* No need to check if there's something to write,
* sowrite wouldn't have been called otherwise
*/
iov[0].iov_base = sb->sb_rptr;
iov[1].iov_base = NULL;
iov[1].iov_len = 0;
if (sb->sb_rptr < sb->sb_wptr) {
iov[0].iov_len = sb->sb_wptr - sb->sb_rptr;
/* Should never succeed, but... */
if (iov[0].iov_len > len)
iov[0].iov_len = len;
n = 1;
} else {
iov[0].iov_len = (sb->sb_data + sb->sb_datalen) - sb->sb_rptr;
if (iov[0].iov_len > len)
iov[0].iov_len = len;
len -= iov[0].iov_len;
if (len) {
iov[1].iov_base = sb->sb_data;
iov[1].iov_len = sb->sb_wptr - sb->sb_data;
if (iov[1].iov_len > len)
iov[1].iov_len = len;
n = 2;
} else
n = 1;
}
/* Check if there's urgent data to send, and if so, send it */
nn = slirp_send(so, iov[0].iov_base, iov[0].iov_len, 0);
/* This should never happen, but people tell me it does *shrug* */
if (nn < 0 && (errno == EAGAIN || errno == EINTR))
return 0;
if (nn <= 0) {
goto err_disconnected;
}
if (n == 2 && nn == iov[0].iov_len) {
int ret;
ret = slirp_send(so, iov[1].iov_base, iov[1].iov_len, 0);
if (ret > 0)
nn += ret;
}
DEBUG_MISC(" ... wrote nn = %d bytes", nn);
/* Update sbuf */
sb->sb_cc -= nn;
sb->sb_rptr += nn;
if (sb->sb_rptr >= (sb->sb_data + sb->sb_datalen))
sb->sb_rptr -= sb->sb_datalen;
/*
* If in DRAIN mode, and there's no more data, set
* it CANTSENDMORE
*/
if ((so->so_state & SS_FWDRAIN) && sb->sb_cc == 0)
sofcantsendmore(so);
return nn;
err_disconnected:
DEBUG_MISC(" --- sowrite disconnected, so->so_state = %x, errno = %d",
so->so_state, errno);
sofcantsendmore(so);
tcp_sockclosed(sototcpcb(so));
return -1;
}
/*
* recvfrom() a UDP socket
*/
void sorecvfrom(struct socket *so)
{
struct sockaddr_storage addr;
struct sockaddr_storage saddr, daddr;
socklen_t addrlen = sizeof(struct sockaddr_storage);
char buff[256];
#ifdef __linux__
ssize_t size;
struct msghdr msg;
struct iovec iov;
char control[1024];
/* First look for errors */
memset(&msg, 0, sizeof(msg));
msg.msg_name = &saddr;
msg.msg_namelen = sizeof(saddr);
msg.msg_control = control;
msg.msg_controllen = sizeof(control);
iov.iov_base = buff;
iov.iov_len = sizeof(buff);
msg.msg_iov = &iov;
msg.msg_iovlen = 1;
size = recvmsg(so->s, &msg, MSG_ERRQUEUE);
if (size >= 0) {
struct cmsghdr *cmsg;
for (cmsg = CMSG_FIRSTHDR(&msg); cmsg; cmsg = CMSG_NXTHDR(&msg, cmsg)) {
if (cmsg->cmsg_level == IPPROTO_IP &&
cmsg->cmsg_type == IP_RECVERR) {
struct sock_extended_err *ee =
(struct sock_extended_err *) CMSG_DATA(cmsg);
if (ee->ee_origin == SO_EE_ORIGIN_ICMP) {
/* Got an ICMP error, forward it */
struct sockaddr_in *sin;
sin = (struct sockaddr_in *) SO_EE_OFFENDER(ee);
icmp_forward_error(so->so_m, ee->ee_type, ee->ee_code,
0, NULL, &sin->sin_addr);
}
}
else if (cmsg->cmsg_level == IPPROTO_IPV6 &&
cmsg->cmsg_type == IPV6_RECVERR) {
struct sock_extended_err *ee =
(struct sock_extended_err *) CMSG_DATA(cmsg);
if (ee->ee_origin == SO_EE_ORIGIN_ICMP6) {
/* Got an ICMPv6 error, forward it */
struct sockaddr_in6 *sin6;
sin6 = (struct sockaddr_in6 *) SO_EE_OFFENDER(ee);
icmp6_forward_error(so->so_m, ee->ee_type, ee->ee_code,
&sin6->sin6_addr);
}
}
}
return;
}
#endif
DEBUG_CALL("sorecvfrom");
DEBUG_ARG("so = %p", so);
if (so->so_type == IPPROTO_ICMP) { /* This is a "ping" reply */
int len;
len = recvfrom(so->s, buff, 256, 0, (struct sockaddr *)&addr, &addrlen);
/* XXX Check if reply is "correct"? */
if (len == -1 || len == 0) {
uint8_t code = ICMP_UNREACH_PORT;
if (errno == EHOSTUNREACH)
code = ICMP_UNREACH_HOST;
else if (errno == ENETUNREACH)
code = ICMP_UNREACH_NET;
DEBUG_MISC(" udp icmp rx errno = %d-%s", errno, strerror(errno));
icmp_send_error(so->so_m, ICMP_UNREACH, code, 0, strerror(errno));
} else {
icmp_reflect(so->so_m);
so->so_m = NULL; /* Don't m_free() it again! */
}
/* No need for this socket anymore, udp_detach it */
udp_detach(so);
} else { /* A "normal" UDP packet */
struct mbuf *m;
int len;
#ifdef _WIN32
unsigned long n;
#else
int n;
#endif
if (ioctlsocket(so->s, FIONREAD, &n) != 0) {
DEBUG_MISC(" ioctlsocket errno = %d-%s\n", errno, strerror(errno));
return;
}
m = m_get(so->slirp);
if (!m) {
return;
}
switch (so->so_ffamily) {
case AF_INET:
m->m_data += IF_MAXLINKHDR + sizeof(struct udpiphdr);
break;
case AF_INET6:
m->m_data +=
IF_MAXLINKHDR + sizeof(struct ip6) + sizeof(struct udphdr);
break;
default:
g_assert_not_reached();
}
/*
* XXX Shouldn't FIONREAD packets destined for port 53,
* but I don't know the max packet size for DNS lookups
*/
len = M_FREEROOM(m);
/* if (so->so_fport != htons(53)) { */
if (n > len) {
n = (m->m_data - m->m_dat) + m->m_len + n + 1;
m_inc(m, n);
len = M_FREEROOM(m);
}
/* } */
m->m_len = recvfrom(so->s, m->m_data, len, 0, (struct sockaddr *)&addr,
&addrlen);
DEBUG_MISC(" did recvfrom %d, errno = %d-%s", m->m_len, errno,
strerror(errno));
if (m->m_len < 0) {
/* Report error as ICMP */
switch (so->so_lfamily) {
uint8_t code;
case AF_INET:
code = ICMP_UNREACH_PORT;
if (errno == EHOSTUNREACH) {
code = ICMP_UNREACH_HOST;
} else if (errno == ENETUNREACH) {
code = ICMP_UNREACH_NET;
}
DEBUG_MISC(" rx error, tx icmp ICMP_UNREACH:%i", code);
icmp_send_error(so->so_m, ICMP_UNREACH, code, 0,
strerror(errno));
break;
case AF_INET6:
code = ICMP6_UNREACH_PORT;
if (errno == EHOSTUNREACH) {
code = ICMP6_UNREACH_ADDRESS;
} else if (errno == ENETUNREACH) {
code = ICMP6_UNREACH_NO_ROUTE;
}
DEBUG_MISC(" rx error, tx icmp6 ICMP_UNREACH:%i", code);
icmp6_send_error(so->so_m, ICMP6_UNREACH, code);
break;
default:
g_assert_not_reached();
}
m_free(m);
} else {
/*
* Hack: domain name lookup will be used the most for UDP,
* and since they'll only be used once there's no need
* for the 4 minute (or whatever) timeout... So we time them
* out much quicker (10 seconds for now...)
*/
if (so->so_expire) {
if (so->so_fport == htons(53))
so->so_expire = curtime + SO_EXPIREFAST;
else
so->so_expire = curtime + SO_EXPIRE;
}
/*
* If this packet was destined for CTL_ADDR,
* make it look like that's where it came from
*/
saddr = addr;
sotranslate_in(so, &saddr);
/* Perform lazy guest IP address resolution if needed. */
if (so->so_state & SS_HOSTFWD) {
if (soassign_guest_addr_if_needed(so) < 0) {
DEBUG_MISC(" guest address not available yet");
switch (so->so_lfamily) {
case AF_INET:
icmp_send_error(so->so_m, ICMP_UNREACH,
ICMP_UNREACH_HOST, 0,
"guest address not available yet");
break;
case AF_INET6:
icmp6_send_error(so->so_m, ICMP6_UNREACH,
ICMP6_UNREACH_ADDRESS);
break;
default:
g_assert_not_reached();
}
m_free(m);
return;
}
}
daddr = so->lhost.ss;
switch (so->so_ffamily) {
case AF_INET:
udp_output(so, m, (struct sockaddr_in *)&saddr,
(struct sockaddr_in *)&daddr, so->so_iptos);
break;
case AF_INET6:
udp6_output(so, m, (struct sockaddr_in6 *)&saddr,
(struct sockaddr_in6 *)&daddr);
break;
default:
g_assert_not_reached();
}
} /* rx error */
} /* if ping packet */
}
/*
* sendto() a socket
*/
int sosendto(struct socket *so, struct mbuf *m)
{
int ret;
struct sockaddr_storage addr;
DEBUG_CALL("sosendto");
DEBUG_ARG("so = %p", so);
DEBUG_ARG("m = %p", m);
addr = so->fhost.ss;
DEBUG_CALL(" sendto()ing)");
if (sotranslate_out(so, &addr) < 0) {
return -1;
}
/* Don't care what port we get */
ret = sendto(so->s, m->m_data, m->m_len, 0, (struct sockaddr *)&addr,
sockaddr_size(&addr));
if (ret < 0)
return -1;
/*
* Kill the socket if there's no reply in 4 minutes,
* but only if it's an expirable socket
*/
if (so->so_expire)
so->so_expire = curtime + SO_EXPIRE;
so->so_state &= SS_PERSISTENT_MASK;
so->so_state |= SS_ISFCONNECTED; /* So that it gets select()ed */
return 0;
}
/*
* Listen for incoming TCP connections
* On failure errno contains the reason.
*/
struct socket *tcpx_listen(Slirp *slirp,
const struct sockaddr *haddr, socklen_t haddrlen,
const struct sockaddr *laddr, socklen_t laddrlen,
int flags)
{
struct socket *so;
int s, opt = 1;
socklen_t addrlen;
DEBUG_CALL("tcpx_listen");
/* AF_INET6 addresses are bigger than AF_INET, so this is big enough. */
char addrstr[INET6_ADDRSTRLEN];
char portstr[6];
int ret;
switch (haddr->sa_family) {
case AF_INET:
case AF_INET6:
ret = getnameinfo(haddr, haddrlen, addrstr, sizeof(addrstr), portstr, sizeof(portstr), NI_NUMERICHOST|NI_NUMERICSERV);
g_assert(ret == 0);
DEBUG_ARG("hfamily = INET");
DEBUG_ARG("haddr = %s", addrstr);
DEBUG_ARG("hport = %s", portstr);
break;
#ifndef _WIN32
case AF_UNIX:
DEBUG_ARG("hfamily = UNIX");
DEBUG_ARG("hpath = %s", ((struct sockaddr_un *) haddr)->sun_path);
break;
#endif
default:
g_assert_not_reached();
}
switch (laddr->sa_family) {
case AF_INET:
case AF_INET6:
ret = getnameinfo(laddr, laddrlen, addrstr, sizeof(addrstr), portstr, sizeof(portstr), NI_NUMERICHOST|NI_NUMERICSERV);
g_assert(ret == 0);
DEBUG_ARG("laddr = %s", addrstr);
DEBUG_ARG("lport = %s", portstr);
break;
default:
g_assert_not_reached();
}
DEBUG_ARG("flags = %x", flags);
/*
* SS_HOSTFWD sockets can be accepted multiple times, so they can't be
* SS_FACCEPTONCE. Also, SS_HOSTFWD connections can be accepted and
* immediately closed if the guest address isn't available yet, which is
* incompatible with the "accept once" concept. Correct code will never
* request both, so disallow their combination by assertion.
*/
g_assert(!((flags & SS_HOSTFWD) && (flags & SS_FACCEPTONCE)));
so = socreate(slirp, IPPROTO_TCP);
/* Don't tcp_attach... we don't need so_snd nor so_rcv */
so->so_tcpcb = tcp_newtcpcb(so);
insque(so, &slirp->tcb);
/*
* SS_FACCEPTONCE sockets must time out.
*/
if (flags & SS_FACCEPTONCE)
so->so_tcpcb->t_timer[TCPT_KEEP] = TCPTV_KEEP_INIT * 2;
so->so_state &= SS_PERSISTENT_MASK;
so->so_state |= (SS_FACCEPTCONN | flags);
sockaddr_copy(&so->lhost.sa, sizeof(so->lhost), laddr, laddrlen);
s = slirp_socket(haddr->sa_family, SOCK_STREAM, 0);
if ((s < 0) ||
(haddr->sa_family == AF_INET6 && slirp_socket_set_v6only(s, (flags & SS_HOSTFWD_V6ONLY) != 0) < 0) ||
(slirp_socket_set_fast_reuse(s) < 0) ||
(bind(s, haddr, haddrlen) < 0) ||
(listen(s, 1) < 0)) {
int tmperrno = errno; /* Don't clobber the real reason we failed */
if (s >= 0) {
closesocket(s);
}
sofree(so);
/* Restore the real errno */
#ifdef _WIN32
WSASetLastError(tmperrno);
#else
errno = tmperrno;
#endif
return NULL;
}
setsockopt(s, SOL_SOCKET, SO_OOBINLINE, &opt, sizeof(int));
slirp_socket_set_nodelay(s);
addrlen = sizeof(so->fhost);
getsockname(s, &so->fhost.sa, &addrlen);
sotranslate_accept(so);
so->s = s;
return so;
}
struct socket *tcp_listen(Slirp *slirp, uint32_t haddr, unsigned hport,
uint32_t laddr, unsigned lport, int flags)
{
struct sockaddr_in hsa, lsa;
memset(&hsa, 0, sizeof(hsa));
hsa.sin_family = AF_INET;
hsa.sin_addr.s_addr = haddr;
hsa.sin_port = hport;
memset(&lsa, 0, sizeof(lsa));
lsa.sin_family = AF_INET;
lsa.sin_addr.s_addr = laddr;
lsa.sin_port = lport;
return tcpx_listen(slirp, (const struct sockaddr *) &hsa, sizeof(hsa), (struct sockaddr *) &lsa, sizeof(lsa), flags);
}
/*
* Various session state calls
* XXX Should be #define's
* The socket state stuff needs work, these often get call 2 or 3
* times each when only 1 was needed
*/
void soisfconnecting(struct socket *so)
{
so->so_state &= ~(SS_NOFDREF | SS_ISFCONNECTED | SS_FCANTRCVMORE |
SS_FCANTSENDMORE | SS_FWDRAIN);
so->so_state |= SS_ISFCONNECTING; /* Clobber other states */
}
void soisfconnected(struct socket *so)
{
so->so_state &= ~(SS_ISFCONNECTING | SS_FWDRAIN | SS_NOFDREF);
so->so_state |= SS_ISFCONNECTED; /* Clobber other states */
}
static void sofcantrcvmore(struct socket *so)
{
if ((so->so_state & SS_NOFDREF) == 0) {
shutdown(so->s, 0);
}
so->so_state &= ~(SS_ISFCONNECTING);
if (so->so_state & SS_FCANTSENDMORE) {
so->so_state &= SS_PERSISTENT_MASK;
so->so_state |= SS_NOFDREF; /* Don't select it */
} else {
so->so_state |= SS_FCANTRCVMORE;
}
}
static void sofcantsendmore(struct socket *so)
{
if ((so->so_state & SS_NOFDREF) == 0) {
shutdown(so->s, 1); /* send FIN to fhost */
}
so->so_state &= ~(SS_ISFCONNECTING);
if (so->so_state & SS_FCANTRCVMORE) {
so->so_state &= SS_PERSISTENT_MASK;
so->so_state |= SS_NOFDREF; /* as above */
} else {
so->so_state |= SS_FCANTSENDMORE;
}
}
/*
* Set write drain mode
* Set CANTSENDMORE once all data has been write()n
*/
void sofwdrain(struct socket *so)
{
if (so->so_rcv.sb_cc)
so->so_state |= SS_FWDRAIN;
else
sofcantsendmore(so);
}
static bool sotranslate_out4(Slirp *s, struct socket *so, struct sockaddr_in *sin)
{
if (!s->disable_dns && so->so_faddr.s_addr == s->vnameserver_addr.s_addr) {
return so->so_fport == htons(53) && get_dns_addr(&sin->sin_addr) >= 0;
}
if (so->so_faddr.s_addr == s->vhost_addr.s_addr ||
so->so_faddr.s_addr == 0xffffffff) {
if (s->disable_host_loopback) {
return false;
}
sin->sin_addr = loopback_addr;
}
return true;
}
static bool sotranslate_out6(Slirp *s, struct socket *so, struct sockaddr_in6 *sin)
{
if (!s->disable_dns && in6_equal(&so->so_faddr6, &s->vnameserver_addr6)) {
uint32_t scope_id;
if (so->so_fport == htons(53) && get_dns6_addr(&sin->sin6_addr, &scope_id) >= 0) {
sin->sin6_scope_id = scope_id;
return true;
}
return false;
}
if (in6_equal_net(&so->so_faddr6, &s->vprefix_addr6, s->vprefix_len) ||
in6_equal(&so->so_faddr6, &(struct in6_addr)ALLNODES_MULTICAST)) {
if (s->disable_host_loopback) {
return false;
}
sin->sin6_addr = in6addr_loopback;
}
return true;
}
/*
* Translate addr in host addr when it is a virtual address
*/
int sotranslate_out(struct socket *so, struct sockaddr_storage *addr)
{
bool ok = true;
switch (addr->ss_family) {
case AF_INET:
ok = sotranslate_out4(so->slirp, so, (struct sockaddr_in *)addr);
break;
case AF_INET6:
ok = sotranslate_out6(so->slirp, so, (struct sockaddr_in6 *)addr);
break;
}
if (!ok) {
errno = EPERM;
return -1;
}
return 0;
}
void sotranslate_in(struct socket *so, struct sockaddr_storage *addr)
{
Slirp *slirp = so->slirp;
struct sockaddr_in *sin = (struct sockaddr_in *)addr;
struct sockaddr_in6 *sin6 = (struct sockaddr_in6 *)addr;
switch (addr->ss_family) {
case AF_INET:
if ((so->so_faddr.s_addr & slirp->vnetwork_mask.s_addr) ==
slirp->vnetwork_addr.s_addr) {
uint32_t inv_mask = ~slirp->vnetwork_mask.s_addr;
if ((so->so_faddr.s_addr & inv_mask) == inv_mask) {
sin->sin_addr = slirp->vhost_addr;
} else if (sin->sin_addr.s_addr == loopback_addr.s_addr ||
so->so_faddr.s_addr != slirp->vhost_addr.s_addr) {
sin->sin_addr = so->so_faddr;
}
}
break;
case AF_INET6:
if (in6_equal_net(&so->so_faddr6, &slirp->vprefix_addr6,
slirp->vprefix_len)) {
if (in6_equal(&sin6->sin6_addr, &in6addr_loopback) ||
!in6_equal(&so->so_faddr6, &slirp->vhost_addr6)) {
sin6->sin6_addr = so->so_faddr6;
}
}
break;
default:
break;
}
}
/*
* Translate connections from localhost to the real hostname
*/
void sotranslate_accept(struct socket *so)
{
Slirp *slirp = so->slirp;
switch (so->so_ffamily) {
case AF_INET:
if (so->so_faddr.s_addr == INADDR_ANY ||
(so->so_faddr.s_addr & loopback_mask) ==
(loopback_addr.s_addr & loopback_mask)) {
so->so_faddr = slirp->vhost_addr;
}
break;
case AF_INET6:
if (in6_equal(&so->so_faddr6, &in6addr_any) ||
in6_equal(&so->so_faddr6, &in6addr_loopback)) {
so->so_faddr6 = slirp->vhost_addr6;
}
break;
case AF_UNIX: {
/* Translate Unix socket to random ephemeral source port. We obtain
* this source port by binding to port 0 so that the OS allocates a
* port for us. If this fails, we fall back to choosing a random port
* with a random number generator. */
int s;
struct sockaddr_in in_addr;
struct sockaddr_in6 in6_addr;
socklen_t in_addr_len;
if (so->slirp->in_enabled) {
so->so_ffamily = AF_INET;
so->so_faddr = slirp->vhost_addr;
so->so_fport = 0;
// TODO Is there a better way of checking socket type?
switch (so->so_type) {
case IPPROTO_TCP:
s = slirp_socket(PF_INET, SOCK_STREAM, 0);
break;
case IPPROTO_UDP:
s = slirp_socket(PF_INET, SOCK_DGRAM, 0);
break;
default:
g_assert_not_reached();
break;
}
if (s < 0) {
g_error("Ephemeral slirp_socket() allocation failed");
goto unix2inet_cont;
}
memset(&in_addr, 0, sizeof(in_addr));
in_addr.sin_family = AF_INET;
in_addr.sin_addr.s_addr = htonl(INADDR_LOOPBACK);
in_addr.sin_port = htons(0);
if (bind(s, (struct sockaddr *) &in_addr, sizeof(in_addr))) {
g_error("Ephemeral bind() failed");
closesocket(s);
goto unix2inet_cont;
}
in_addr_len = sizeof(in_addr);
if (getsockname(s, (struct sockaddr *) &in_addr, &in_addr_len)) {
g_error("Ephemeral getsockname() failed");
closesocket(s);
goto unix2inet_cont;
}
so->s_aux = s;
so->so_fport = in_addr.sin_port;
unix2inet_cont:
if (!so->so_fport) {
g_warning("Falling back to random port allocation");
so->so_fport = htons(g_rand_int_range(slirp->grand, 49152, 65536));
}
} else if (so->slirp->in6_enabled) {
so->so_ffamily = AF_INET6;
so->so_faddr6 = slirp->vhost_addr6;
so->so_fport6 = 0;
switch (so->so_type) {
case IPPROTO_TCP:
s = slirp_socket(PF_INET6, SOCK_STREAM, 0);
break;
case IPPROTO_UDP:
s = slirp_socket(PF_INET6, SOCK_DGRAM, 0);
break;
default:
g_assert_not_reached();
break;
}
if (s < 0) {
g_error("Ephemeral slirp_socket() allocation failed");
goto unix2inet6_cont;
}
memset(&in6_addr, 0, sizeof(in6_addr));
in6_addr.sin6_family = AF_INET6;
in6_addr.sin6_addr = in6addr_loopback;
in6_addr.sin6_port = htons(0);
if (bind(s, (struct sockaddr *) &in6_addr, sizeof(in6_addr))) {
g_error("Ephemeral bind() failed");
closesocket(s);
goto unix2inet6_cont;
}
in_addr_len = sizeof(in6_addr);
if (getsockname(s, (struct sockaddr *) &in6_addr, &in_addr_len)) {
g_error("Ephemeral getsockname() failed");
closesocket(s);
goto unix2inet6_cont;
}
so->s_aux = s;
so->so_fport6 = in6_addr.sin6_port;
unix2inet6_cont:
if (!so->so_fport6) {
g_warning("Falling back to random port allocation");
so->so_fport6 = htons(g_rand_int_range(slirp->grand, 49152, 65536));
}
} else {
g_assert_not_reached();
}
break;
} /* case AF_UNIX */
default:
break;
}
}
void sodrop(struct socket *s, int num)
{
if (sbdrop(&s->so_snd, num)) {
s->slirp->cb->notify(s->slirp->opaque);
}
}
/*
* Translate "addr-any" in so->lhost to the guest's actual address.
* Returns 0 for success, or -1 if the guest doesn't have an address yet
* with errno set to EHOSTUNREACH.
*
* The guest address is taken from the first entry in the ARP table for IPv4
* and the first entry in the NDP table for IPv6.
* Note: The IPv4 path isn't exercised yet as all hostfwd "" guest translations
* are handled immediately by using slirp->vdhcp_startaddr.
*/
int soassign_guest_addr_if_needed(struct socket *so)
{
Slirp *slirp = so->slirp;
/* AF_INET6 addresses are bigger than AF_INET, so this is big enough. */
char addrstr[INET6_ADDRSTRLEN];
char portstr[6];
g_assert(so->so_state & SS_HOSTFWD);
switch (so->so_ffamily) {
case AF_INET:
if (so->so_laddr.s_addr == INADDR_ANY) {
g_assert_not_reached();
}
break;
case AF_INET6:
if (in6_zero(&so->so_laddr6)) {
int ret;
if (in6_zero(&slirp->ndp_table.guest_in6_addr)) {
errno = EHOSTUNREACH;
return -1;
}
so->so_laddr6 = slirp->ndp_table.guest_in6_addr;
ret = getnameinfo((const struct sockaddr *) &so->lhost.ss,
sizeof(so->lhost.ss), addrstr, sizeof(addrstr),
portstr, sizeof(portstr),
NI_NUMERICHOST|NI_NUMERICSERV);
g_assert(ret == 0);
DEBUG_MISC("%s: new ip = [%s]:%s", __func__, addrstr, portstr);
}
break;
default:
break;
}
return 0;
}
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