qemu/slirp/socket.c

718 lines
17 KiB
C

/*
* Copyright (c) 1995 Danny Gasparovski.
*
* Please read the file COPYRIGHT for the
* terms and conditions of the copyright.
*/
#define WANT_SYS_IOCTL_H
#include <slirp.h>
#include "ip_icmp.h"
#include "main.h"
#ifdef __sun__
#include <sys/filio.h>
#endif
void
so_init()
{
/* Nothing yet */
}
struct socket *
solookup(head, laddr, lport, faddr, fport)
struct socket *head;
struct in_addr laddr;
u_int lport;
struct in_addr faddr;
u_int fport;
{
struct socket *so;
for (so = head->so_next; so != head; so = so->so_next) {
if (so->so_lport == lport &&
so->so_laddr.s_addr == laddr.s_addr &&
so->so_faddr.s_addr == faddr.s_addr &&
so->so_fport == fport)
break;
}
if (so == head)
return (struct socket *)NULL;
return so;
}
/*
* 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()
{
struct socket *so;
so = (struct socket *)malloc(sizeof(struct socket));
if(so) {
memset(so, 0, sizeof(struct socket));
so->so_state = SS_NOFDREF;
so->s = -1;
}
return(so);
}
/*
* remque and free a socket, clobber cache
*/
void
sofree(so)
struct socket *so;
{
if (so->so_emu==EMU_RSH && so->extra) {
sofree(so->extra);
so->extra=NULL;
}
if (so == tcp_last_so)
tcp_last_so = &tcb;
else if (so == udp_last_so)
udp_last_so = &udb;
m_free(so->so_m);
if(so->so_next && so->so_prev)
remque(so); /* crashes if so is not in a queue */
free(so);
}
/*
* 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(so)
struct socket *so;
{
int n, nn, lss, total;
struct sbuf *sb = &so->so_snd;
int len = sb->sb_datalen - sb->sb_cc;
struct iovec iov[2];
int mss = so->so_tcpcb->t_maxseg;
DEBUG_CALL("soread");
DEBUG_ARG("so = %lx", (long )so);
/*
* No need to check if there's enough room to read.
* soread wouldn't have been called if there weren't
*/
len = sb->sb_datalen - sb->sb_cc;
iov[0].iov_base = sb->sb_wptr;
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;
}
}
#ifdef HAVE_READV
nn = readv(so->s, (struct iovec *)iov, n);
DEBUG_MISC((dfd, " ... read nn = %d bytes\n", nn));
#else
nn = recv(so->s, iov[0].iov_base, iov[0].iov_len,0);
#endif
if (nn <= 0) {
if (nn < 0 && (errno == EINTR || errno == EAGAIN))
return 0;
else {
DEBUG_MISC((dfd, " --- soread() disconnected, nn = %d, errno = %d-%s\n", nn, errno,strerror(errno)));
sofcantrcvmore(so);
tcp_sockclosed(sototcpcb(so));
return -1;
}
}
#ifndef HAVE_READV
/*
* 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 wont (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((dfd, " ... read nn = %d bytes\n", nn));
#endif
/* 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;
}
/*
* 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
*/
void
sorecvoob(so)
struct socket *so;
{
struct tcpcb *tp = sototcpcb(so);
DEBUG_CALL("sorecvoob");
DEBUG_ARG("so = %lx", (long)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.
*/
soread(so);
tp->snd_up = tp->snd_una + so->so_snd.sb_cc;
tp->t_force = 1;
tcp_output(tp);
tp->t_force = 0;
}
/*
* Send urgent data
* There's a lot duplicated code here, but...
*/
int
sosendoob(so)
struct socket *so;
{
struct sbuf *sb = &so->so_rcv;
char buff[2048]; /* XXX Shouldn't be sending more oob data than this */
int n, len;
DEBUG_CALL("sosendoob");
DEBUG_ARG("so = %lx", (long)so);
DEBUG_ARG("sb->sb_cc = %d", sb->sb_cc);
if (so->so_urgc > 2048)
so->so_urgc = 2048; /* XXXX */
if (sb->sb_rptr < sb->sb_wptr) {
/* We can send it directly */
n = send(so->s, sb->sb_rptr, so->so_urgc, (MSG_OOB)); /* |MSG_DONTWAIT)); */
so->so_urgc -= n;
DEBUG_MISC((dfd, " --- sent %d bytes urgent data, %d urgent bytes left\n", n, so->so_urgc));
} else {
/*
* Since there's no sendv or sendtov like writev,
* we must copy all data to a linear buffer then
* send it all
*/
len = (sb->sb_data + sb->sb_datalen) - sb->sb_rptr;
if (len > so->so_urgc) len = so->so_urgc;
memcpy(buff, sb->sb_rptr, len);
so->so_urgc -= len;
if (so->so_urgc) {
n = sb->sb_wptr - sb->sb_data;
if (n > so->so_urgc) n = so->so_urgc;
memcpy((buff + len), sb->sb_data, n);
so->so_urgc -= n;
len += n;
}
n = send(so->s, buff, len, (MSG_OOB)); /* |MSG_DONTWAIT)); */
#ifdef DEBUG
if (n != len)
DEBUG_ERROR((dfd, "Didn't send all data urgently XXXXX\n"));
#endif
DEBUG_MISC((dfd, " ---2 sent %d bytes urgent data, %d urgent bytes left\n", 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(so)
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 = %lx", (long)so);
if (so->so_urgc) {
sosendoob(so);
if (sb->sb_cc == 0)
return 0;
}
/*
* No need to check if there's something to write,
* sowrite wouldn't have been called otherwise
*/
len = sb->sb_cc;
iov[0].iov_base = sb->sb_rptr;
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 */
#ifdef HAVE_READV
nn = writev(so->s, (const struct iovec *)iov, n);
DEBUG_MISC((dfd, " ... wrote nn = %d bytes\n", nn));
#else
nn = send(so->s, iov[0].iov_base, iov[0].iov_len,0);
#endif
/* This should never happen, but people tell me it does *shrug* */
if (nn < 0 && (errno == EAGAIN || errno == EINTR))
return 0;
if (nn <= 0) {
DEBUG_MISC((dfd, " --- sowrite disconnected, so->so_state = %x, errno = %d\n",
so->so_state, errno));
sofcantsendmore(so);
tcp_sockclosed(sototcpcb(so));
return -1;
}
#ifndef HAVE_READV
if (n == 2 && nn == iov[0].iov_len) {
int ret;
ret = send(so->s, iov[1].iov_base, iov[1].iov_len,0);
if (ret > 0)
nn += ret;
}
DEBUG_MISC((dfd, " ... wrote nn = %d bytes\n", nn));
#endif
/* 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;
}
/*
* recvfrom() a UDP socket
*/
void
sorecvfrom(so)
struct socket *so;
{
struct sockaddr_in addr;
int addrlen = sizeof(struct sockaddr_in);
DEBUG_CALL("sorecvfrom");
DEBUG_ARG("so = %lx", (long)so);
if (so->so_type == IPPROTO_ICMP) { /* This is a "ping" reply */
char buff[256];
int len;
len = recvfrom(so->s, buff, 256, 0,
(struct sockaddr *)&addr, &addrlen);
/* XXX Check if reply is "correct"? */
if(len == -1 || len == 0) {
u_char code=ICMP_UNREACH_PORT;
if(errno == EHOSTUNREACH) code=ICMP_UNREACH_HOST;
else if(errno == ENETUNREACH) code=ICMP_UNREACH_NET;
DEBUG_MISC((dfd," udp icmp rx errno = %d-%s\n",
errno,strerror(errno)));
icmp_error(so->so_m, ICMP_UNREACH,code, 0,strerror(errno));
} else {
icmp_reflect(so->so_m);
so->so_m = 0; /* 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, n;
if (!(m = m_get())) return;
m->m_data += if_maxlinkhdr;
/*
* 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)) { */
ioctlsocket(so->s, FIONREAD, &n);
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((dfd, " did recvfrom %d, errno = %d-%s\n",
m->m_len, errno,strerror(errno)));
if(m->m_len<0) {
u_char code=ICMP_UNREACH_PORT;
if(errno == EHOSTUNREACH) code=ICMP_UNREACH_HOST;
else if(errno == ENETUNREACH) code=ICMP_UNREACH_NET;
DEBUG_MISC((dfd," rx error, tx icmp ICMP_UNREACH:%i\n", code));
icmp_error(so->so_m, ICMP_UNREACH,code, 0,strerror(errno));
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 (m->m_len == len) {
* m_inc(m, MINCSIZE);
* m->m_len = 0;
* }
*/
/*
* If this packet was destined for CTL_ADDR,
* make it look like that's where it came from, done by udp_output
*/
udp_output(so, m, &addr);
} /* rx error */
} /* if ping packet */
}
/*
* sendto() a socket
*/
int
sosendto(so, m)
struct socket *so;
struct mbuf *m;
{
int ret;
struct sockaddr_in addr;
DEBUG_CALL("sosendto");
DEBUG_ARG("so = %lx", (long)so);
DEBUG_ARG("m = %lx", (long)m);
addr.sin_family = AF_INET;
if ((so->so_faddr.s_addr & htonl(0xffffff00)) == special_addr.s_addr) {
/* It's an alias */
switch(ntohl(so->so_faddr.s_addr) & 0xff) {
case CTL_DNS:
addr.sin_addr = dns_addr;
break;
case CTL_ALIAS:
default:
addr.sin_addr = loopback_addr;
break;
}
} else
addr.sin_addr = so->so_faddr;
addr.sin_port = so->so_fport;
DEBUG_MISC((dfd, " sendto()ing, addr.sin_port=%d, addr.sin_addr.s_addr=%.16s\n", ntohs(addr.sin_port), inet_ntoa(addr.sin_addr)));
/* Don't care what port we get */
ret = sendto(so->s, m->m_data, m->m_len, 0,
(struct sockaddr *)&addr, sizeof (struct sockaddr));
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_ISFCONNECTED; /* So that it gets select()ed */
return 0;
}
/*
* XXX This should really be tcp_listen
*/
struct socket *
solisten(port, laddr, lport, flags)
u_int port;
u_int32_t laddr;
u_int lport;
int flags;
{
struct sockaddr_in addr;
struct socket *so;
int s, addrlen = sizeof(addr), opt = 1;
DEBUG_CALL("solisten");
DEBUG_ARG("port = %d", port);
DEBUG_ARG("laddr = %x", laddr);
DEBUG_ARG("lport = %d", lport);
DEBUG_ARG("flags = %x", flags);
if ((so = socreate()) == NULL) {
/* free(so); Not sofree() ??? free(NULL) == NOP */
return NULL;
}
/* Don't tcp_attach... we don't need so_snd nor so_rcv */
if ((so->so_tcpcb = tcp_newtcpcb(so)) == NULL) {
free(so);
return NULL;
}
insque(so,&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_FACCEPTCONN|flags);
so->so_lport = lport; /* Kept in network format */
so->so_laddr.s_addr = laddr; /* Ditto */
addr.sin_family = AF_INET;
addr.sin_addr.s_addr = INADDR_ANY;
addr.sin_port = port;
if (((s = socket(AF_INET,SOCK_STREAM,0)) < 0) ||
(setsockopt(s,SOL_SOCKET,SO_REUSEADDR,(char *)&opt,sizeof(int)) < 0) ||
(bind(s,(struct sockaddr *)&addr, sizeof(addr)) < 0) ||
(listen(s,1) < 0)) {
int tmperrno = errno; /* Don't clobber the real reason we failed */
close(s);
sofree(so);
/* Restore the real errno */
#ifdef _WIN32
WSASetLastError(tmperrno);
#else
errno = tmperrno;
#endif
return NULL;
}
setsockopt(s,SOL_SOCKET,SO_OOBINLINE,(char *)&opt,sizeof(int));
getsockname(s,(struct sockaddr *)&addr,&addrlen);
so->so_fport = addr.sin_port;
if (addr.sin_addr.s_addr == 0 || addr.sin_addr.s_addr == loopback_addr.s_addr)
so->so_faddr = alias_addr;
else
so->so_faddr = addr.sin_addr;
so->s = s;
return so;
}
/*
* Data is available in so_rcv
* Just write() the data to the socket
* XXX not yet...
*/
void
sorwakeup(so)
struct socket *so;
{
/* sowrite(so); */
/* FD_CLR(so->s,&writefds); */
}
/*
* Data has been freed in so_snd
* We have room for a read() if we want to
* For now, don't read, it'll be done in the main loop
*/
void
sowwakeup(so)
struct socket *so;
{
/* Nothing, yet */
}
/*
* 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(so)
register 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(so)
register struct socket *so;
{
so->so_state &= ~(SS_ISFCONNECTING|SS_FWDRAIN|SS_NOFDREF);
so->so_state |= SS_ISFCONNECTED; /* Clobber other states */
}
void
sofcantrcvmore(so)
struct socket *so;
{
if ((so->so_state & SS_NOFDREF) == 0) {
shutdown(so->s,0);
if(global_writefds) {
FD_CLR(so->s,global_writefds);
}
}
so->so_state &= ~(SS_ISFCONNECTING);
if (so->so_state & SS_FCANTSENDMORE)
so->so_state = SS_NOFDREF; /* Don't select it */ /* XXX close() here as well? */
else
so->so_state |= SS_FCANTRCVMORE;
}
void
sofcantsendmore(so)
struct socket *so;
{
if ((so->so_state & SS_NOFDREF) == 0) {
shutdown(so->s,1); /* send FIN to fhost */
if (global_readfds) {
FD_CLR(so->s,global_readfds);
}
if (global_xfds) {
FD_CLR(so->s,global_xfds);
}
}
so->so_state &= ~(SS_ISFCONNECTING);
if (so->so_state & SS_FCANTRCVMORE)
so->so_state = SS_NOFDREF; /* as above */
else
so->so_state |= SS_FCANTSENDMORE;
}
void
soisfdisconnected(so)
struct socket *so;
{
/* so->so_state &= ~(SS_ISFCONNECTING|SS_ISFCONNECTED); */
/* close(so->s); */
/* so->so_state = SS_ISFDISCONNECTED; */
/*
* XXX Do nothing ... ?
*/
}
/*
* Set write drain mode
* Set CANTSENDMORE once all data has been write()n
*/
void
sofwdrain(so)
struct socket *so;
{
if (so->so_rcv.sb_cc)
so->so_state |= SS_FWDRAIN;
else
sofcantsendmore(so);
}