udp_usrreq.c

MIPS处理器的bootloader,龙芯就是用的修改过的PMON2

	    /*
	     * This cruft is needed to deliver a IPv4 packet to
	     * an AF_INET6 socket.
	     */
	    ((((struct inpcb *)inp->inp_socket->so_pcb)->inp_flags & INP_IPV6)
	    && ip) ? (struct sockaddr *)&src_v4mapped : 
#endif /* INET6 */
		&srcsa.sa, m, opts) == 0) {
		udpstat.udps_fullsock++;
		goto bad;
	}
	sorwakeup(inp->inp_socket);
	return;
bad:
	m_freem(m);
	if (opts)
		m_freem(opts);
}

/*
 * Create a "control" mbuf containing the specified data
 * with the specified type for presentation with a datagram.
 */
struct mbuf *
udp_saveopt(p, size, type)
	caddr_t p;
	register int size;
	int type;
{
	register struct cmsghdr *cp;
	struct mbuf *m;

	if ((m = m_get(M_DONTWAIT, MT_CONTROL)) == NULL)
		return ((struct mbuf *) NULL);
	cp = (struct cmsghdr *) mtod(m, struct cmsghdr *);
	bcopy(p, CMSG_DATA(cp), size);
	size += sizeof(*cp);
	m->m_len = size;
	cp->cmsg_len = size;
	cp->cmsg_level = IPPROTO_IP;
	cp->cmsg_type = type;
	return (m);
}

/*
 * Notify a udp user of an asynchronous error;
 * just wake up so that he can collect error status.
 */
static void
udp_notify(inp, errno)
	register struct inpcb *inp;
	int errno;
{
	inp->inp_socket->so_error = errno;
	sorwakeup(inp->inp_socket);
	sowwakeup(inp->inp_socket);
}

void *
udp_ctlinput(cmd, sa, v)
	int cmd;
	struct sockaddr *sa;
	void *v;
{
	register struct ip *ip = v;
	register struct udphdr *uh;
	extern int inetctlerrmap[];
	void (*notify) __P((struct inpcb *, int)) = udp_notify;
	int errno;

	if ((unsigned)cmd >= PRC_NCMDS)
		return NULL;
	errno = inetctlerrmap[cmd];
	if (PRC_IS_REDIRECT(cmd))
		notify = in_rtchange, ip = 0;
	else if (cmd == PRC_HOSTDEAD)
		ip = 0;
	else if (errno == 0)
		return NULL;
#ifdef INET6
	if (sa->sa_family == AF_INET6) {
		if (ip) {
			struct ipv6 *ipv6 = (struct ipv6 *)ip;
		
			uh = (struct udphdr *)((caddr_t)ipv6 + sizeof(struct ipv6));
			in6_pcbnotify(&udbtable, sa, uh->uh_dport,
			    &(ipv6->ipv6_src), uh->uh_sport, cmd, udp_notify);
		} else
			in6_pcbnotify(&udbtable, sa, 0,
			    (struct in6_addr *)&in6addr_any, 0, cmd, udp_notify);
	} else
#endif /* INET6 */
	if (ip) {
		uh = (struct udphdr *)((caddr_t)ip + (ip->ip_hl << 2));
		in_pcbnotify(&udbtable, sa, uh->uh_dport, ip->ip_src,
		    uh->uh_sport, errno, notify);
	} else
		in_pcbnotifyall(&udbtable, sa, errno, notify);
	return NULL;
}

int
#if __STDC__
udp_output(struct mbuf *m, ...)
#else
udp_output(m, va_alist)
	struct mbuf *m;
	va_dcl
#endif
{
	register struct inpcb *inp;
	struct mbuf *addr, *control;
	register struct udpiphdr *ui;
	register int len = m->m_pkthdr.len;
	struct in_addr laddr;
	int s = 0, error = 0;
	va_list ap;
#ifdef INET6
	register struct in6_addr laddr6;
	int v6packet = 0;
	struct ifnet *forceif = NULL;
#endif /* INET6 */
	int pcbflags = 0;

	va_start(ap, m);
	inp = va_arg(ap, struct inpcb *);
	addr = va_arg(ap, struct mbuf *);
	control = va_arg(ap, struct mbuf *);
	va_end(ap);

#ifndef INET6
	if (control)
		m_freem(control);		/* XXX */
#endif /* INET6 */

	if (addr) {
	        /*
		 * Save current PCB flags because they may change during
		 * temporary connection, particularly the INP_IPV6_UNDEC
		 * flag.
		 */
                pcbflags = inp->inp_flags;

#ifdef INET6
	        if (inp->inp_flags & INP_IPV6)
			laddr6 = inp->inp_laddr6;
		else  
#endif /* INET6 */
			laddr = inp->inp_laddr;
#ifdef INET6
		if (((inp->inp_flags & INP_IPV6) &&
		    !IN6_IS_ADDR_UNSPECIFIED(&inp->inp_faddr6)) ||
		    (inp->inp_faddr.s_addr != INADDR_ANY)) {
#else /* INET6 */
		if (inp->inp_faddr.s_addr != INADDR_ANY) {
#endif /* INET6 */
			error = EISCONN;
			goto release;
		}
		/*
		 * Must block input while temporarily connected.
		 */
		s = splsoftnet();
		error = in_pcbconnect(inp, addr);
		if (error) {
			splx(s);
			goto release;
		}
	} else {
#ifdef INET6
	        if (((inp->inp_flags & INP_IPV6) && 
		    IN6_IS_ADDR_UNSPECIFIED(&inp->inp_faddr6)) ||
		    (inp->inp_faddr.s_addr == INADDR_ANY)) {
#else /* INET6 */
		if (inp->inp_faddr.s_addr == INADDR_ANY) {
#endif /* INET6 */
			error = ENOTCONN;
			goto release;
		}
	}
	/*
	 * Calculate data length and get a mbuf
	 * for UDP and IP headers.
	 */
#ifdef INET6
	/*
	 * Handles IPv4-mapped IPv6 address because temporary connect sets
	 * the right flag.
	 */
	v6packet = ((inp->inp_flags & INP_IPV6) &&
		    !(inp->inp_flags & INP_IPV6_MAPPED));

	if (!v6packet && control)
		m_freem(control);

	M_PREPEND(m, v6packet ? (sizeof(struct udphdr) +
	    sizeof(struct ipv6)) : sizeof(struct udpiphdr), M_DONTWAIT);
#else /* INET6 */
	M_PREPEND(m, sizeof(struct udpiphdr), M_DONTWAIT);
#endif /* INET6 */
	if (m == 0) {
		error = ENOBUFS;
		goto bail;
	}

	/*
	 * Compute the packet length of the IP header, and
	 * punt if the length looks bogus.
	 */
	if ((len + sizeof(struct udpiphdr)) > IP_MAXPACKET) {
		error = EMSGSIZE;
		goto release;
	}

	/*
	 * Fill in mbuf with extended UDP header
	 * and addresses and length put into network format.
	 */
#ifdef INET6
	if (v6packet) {
		struct ipv6 *ipv6 = mtod(m, struct ipv6 *);
		struct udphdr *uh = (struct udphdr *)(mtod(m, caddr_t) +
		    sizeof(struct ipv6));
		int payload = sizeof(struct ipv6);

		ipv6->ipv6_versfl = htonl(0x60000000) |
		    (inp->inp_ipv6.ipv6_versfl & htonl(0x0fffffff)); 
	  
		ipv6->ipv6_hoplimit = inp->inp_ipv6.ipv6_hoplimit;
		ipv6->ipv6_nexthdr = IPPROTO_UDP;
		ipv6->ipv6_src = inp->inp_laddr6;
		ipv6->ipv6_dst = inp->inp_faddr6;
		ipv6->ipv6_length = (u_short)len + sizeof(struct udphdr);

		uh->uh_sport = inp->inp_lport;
		uh->uh_dport = inp->inp_fport;
		uh->uh_ulen = htons(ipv6->ipv6_length);
		uh->uh_sum = 0;

		if (control)
			if ((error = ipv6_controltoheader(&m, control,
			    &forceif, &payload)))
				goto release;

		/* 
		 * Always calculate udp checksum for IPv6 datagrams
		 */
		if (!(uh->uh_sum = in6_cksum(m, IPPROTO_UDP, len +
		    sizeof(struct udphdr), payload))) 
			uh->uh_sum = 0xffff;

		error = ipv6_output(m, &inp->inp_route6, 
		    inp->inp_socket->so_options & SO_DONTROUTE,
		    (inp->inp_flags & INP_IPV6_MCAST)?inp->inp_moptions6:NULL,
		    forceif, inp->inp_socket);
	} else
#endif /* INET6 */
	{
		ui = mtod(m, struct udpiphdr *);
		bzero(ui->ui_x1, sizeof ui->ui_x1);
		ui->ui_pr = IPPROTO_UDP;
		ui->ui_len = htons((u_int16_t)len + sizeof (struct udphdr));
		ui->ui_src = inp->inp_laddr;
		ui->ui_dst = inp->inp_faddr;
		ui->ui_sport = inp->inp_lport;
		ui->ui_dport = inp->inp_fport;
		ui->ui_ulen = ui->ui_len;

		/*
		 * Stuff checksum and output datagram.
		 */

		ui->ui_sum = 0;
		if (udpcksum) {
			if ((ui->ui_sum = in_cksum(m, sizeof (struct udpiphdr) +
			    len)) == 0)
				ui->ui_sum = 0xffff;
		}
		((struct ip *)ui)->ip_len = sizeof (struct udpiphdr) + len;
#ifdef INET6
		/*
		 *  For now, we use the default values for ttl and tos for 
		 *  v4 packets sent using a v6 pcb.  We probably want to
		 *  later allow v4 setsockopt operations on a v6 socket to 
		 *  modify the ttl and tos for v4 packets sent using
		 *  the mapped address format.  We really ought to
		 *  save the v4 ttl and v6 hoplimit in separate places 
		 *  instead of craming both in the inp_hu union.
		 */
		if (inp->inp_flags & INP_IPV6) {
			((struct ip *)ui)->ip_ttl = ip_defttl;
			((struct ip *)ui)->ip_tos = 0;	  
		} else
#endif /* INET6 */
		{
			((struct ip *)ui)->ip_ttl = inp->inp_ip.ip_ttl;	
			((struct ip *)ui)->ip_tos = inp->inp_ip.ip_tos;
		}

		udpstat.udps_opackets++;
#ifdef INET6
		if (inp->inp_flags & INP_IPV6_MCAST)
			error = ip_output(m, inp->inp_options, &inp->inp_route,
				inp->inp_socket->so_options &
				(SO_DONTROUTE | SO_BROADCAST),
				NULL, NULL, inp->inp_socket);
		else
#endif /* INET6 */
			error = ip_output(m, inp->inp_options, &inp->inp_route,
				inp->inp_socket->so_options &
				(SO_DONTROUTE | SO_BROADCAST),
		    		inp->inp_moptions, inp, NULL);
	}

bail:
	if (addr) {
		in_pcbdisconnect(inp);
                inp->inp_flags = pcbflags;
#ifdef INET6
		if (inp->inp_flags & INP_IPV6)
			inp->inp_laddr6 = laddr6;
	        else
#endif /* INET6 */
		inp->inp_laddr = laddr;
		splx(s);
	}
	return (error);

release:
	m_freem(m);
	return (error);
}

u_int	udp_sendspace = 9216;		/* really max datagram size */
u_int	udp_recvspace = 40 * (1024 + sizeof(struct sockaddr_in));
					/* 40 1K datagrams */

/*ARGSUSED*/
int
udp_usrreq(so, req, m, addr, control)
	struct socket *so;
	int req;
	struct mbuf *m, *addr, *control;
{
	struct inpcb *inp = sotoinpcb(so);
	int error = 0;
	int s;

	if (req == PRU_CONTROL) {
#ifdef INET6
		if (inp->inp_flags & INP_IPV6)
			return (in6_control(so, (u_long)m, (caddr_t)addr,
			    (struct ifnet *)control, 0));
		else
#endif /* INET6 */
			return (in_control(so, (u_long)m, (caddr_t)addr,
			    (struct ifnet *)control));
	}
	if (inp == NULL && req != PRU_ATTACH) {
		error = EINVAL;
		goto release;
	}
	/*
	 * Note: need to block udp_input while changing
	 * the udp pcb queue and/or pcb addresses.
	 */
	switch (req) {

	case PRU_ATTACH:
		if (inp != NULL) {
			error = EINVAL;
			break;
		}
		s = splsoftnet();
		error = in_pcballoc(so, &udbtable);
		splx(s);
		if (error)
			break;
		error = soreserve(so, udp_sendspace, udp_recvspace);
		if (error)
			break;
#ifdef INET6
		if (((struct inpcb *)so->so_pcb)->inp_flags & INP_IPV6)
			((struct inpcb *) so->so_pcb)->inp_ipv6.ipv6_hoplimit =
			    ipv6_defhoplmt;
		else
#endif /* INET6 */
			((struct inpcb *) so->so_pcb)->inp_ip.ip_ttl = ip_defttl;
		break;

	case PRU_DETACH:
		udp_detach(inp);
		break;

	case PRU_BIND:
		s = splsoftnet();
		error = in_pcbbind(inp, addr);
		splx(s);
		break;

	case PRU_LISTEN:
		error = EOPNOTSUPP;
		break;

	case PRU_CONNECT:
#ifdef INET6 
		if (inp->inp_flags & INP_IPV6) {
			if (!IN6_IS_ADDR_UNSPECIFIED(&inp->inp_faddr6)) {
				error = EISCONN;
				break;
			}
		} else
#endif /* INET6 */
			if (inp->inp_faddr.s_addr != INADDR_ANY) {
				error = EISCONN;
				break;
			}

		s = splsoftnet();
		error = in_pcbconnect(inp, addr);
		splx(s);
		if (error == 0)
			soisconnected(so);
		break;

	case PRU_CONNECT2:
		error = EOPNOTSUPP;
		break;

	case PRU_ACCEPT:
		error = EOPNOTSUPP;
		break;

	case PRU_DISCONNECT:
#ifdef INET6 
		if (inp->inp_flags & INP_IPV6) {
			if (IN6_IS_ADDR_UNSPECIFIED(&inp->inp_faddr6)) {
				error = ENOTCONN;
				break;
			}
		} else
#endif /* INET6 */
			if (inp->inp_faddr.s_addr == INADDR_ANY) {
				error = ENOTCONN;
				break;
			}

		s = splsoftnet();
		in_pcbdisconnect(inp);
#ifdef INET6
		if (inp->inp_flags & INP_IPV6)
			inp->inp_laddr6 = in6addr_any;
		else
#endif /* INET6 */
			inp->inp_laddr.s_addr = INADDR_ANY;

		splx(s);
		so->so_state &= ~SS_ISCONNECTED;		/* XXX */
		break;

	case PRU_SHUTDOWN:
		socantsendmore(so);
		break;

	case PRU_SEND:
#ifdef IPSEC
		error = check_ipsec_policy(inp,0);
		if (error)
			return (error);
#endif
		return (udp_output(m, inp, addr, control));

	case PRU_ABORT:
		soisdisconnected(so);
		udp_detach(inp);
		break;

	case PRU_SOCKADDR:
		in_setsockaddr(inp, addr);
		break;

	case PRU_PEERADDR:
		in_setpeeraddr(inp, addr);
		break;

	case PRU_SENSE:
		/*
		 * stat: don't bother with a blocksize.
		 */
		/*
		 * Perhaps Path MTU might be returned for a connected
		 * UDP socket in this case.
		 */
		return (0);

	case PRU_SENDOOB:
	case PRU_FASTTIMO:
	case PRU_SLOWTIMO:
	case PRU_PROTORCV:
	case PRU_PROTOSEND:
		error =  EOPNOTSUPP;
		break;

	case PRU_RCVD:
	case PRU_RCVOOB:
		return (EOPNOTSUPP);	/* do not free mbuf's */

	default:
		panic("udp_usrreq");
	}

release:
	if (control) {
		printf("udp control data unexpectedly retained\n");
		m_freem(control);
	}
	if (m)
		m_freem(m);
	return (error);
}

static void
udp_detach(inp)
	struct inpcb *inp;
{
	int s = splsoftnet();

	in_pcbdetach(inp);
	splx(s);
}

/*
 * Sysctl for udp variables.
 */
int
udp_sysctl(name, namelen, oldp, oldlenp, newp, newlen)
	int *name;
	u_int namelen;
	void *oldp;
	size_t *oldlenp;
	void *newp;
	size_t newlen;
{
	/* All sysctl names at this level are terminal. */
	if (namelen != 1)
		return (ENOTDIR);

	switch (name[0]) {
	case UDPCTL_CHECKSUM:
		return (sysctl_int(oldp, oldlenp, newp, newlen, &udpcksum));
	case UDPCTL_BADDYNAMIC:
		return (sysctl_struct(oldp, oldlenp, newp, newlen,
		    baddynamicports.udp, sizeof(baddynamicports.udp)));
	case UDPCTL_RECVSPACE:
		return (sysctl_int(oldp, oldlenp, newp, newlen,&udp_recvspace));
	case UDPCTL_SENDSPACE:
		return (sysctl_int(oldp, oldlenp, newp, newlen,&udp_sendspace));
	default:
		return (ENOPROTOOPT);
	}
	/* NOTREACHED */
}