Initial revision

1 files changed, 735 insertions, 0 deletions

diff --git a/pfinet/linux-inet/udp.c b/pfinet/linux-inet/udp.c
new file mode 100644
index 00000000..74912cbd
--- /dev/null
+++ b/pfinet/linux-inet/udp.c
@@ -0,0 +1,735 @@
+/*
+ * INET		An implementation of the TCP/IP protocol suite for the LINUX
+ *		operating system.  INET is implemented using the  BSD Socket
+ *		interface as the means of communication with the user level.
+ *
+ *		The User Datagram Protocol (UDP).
+ *
+ * Version:	@(#)udp.c	1.0.13	06/02/93
+ *
+ * Authors:	Ross Biro, <bir7@leland.Stanford.Edu>
+ *		Fred N. van Kempen, <waltje@uWalt.NL.Mugnet.ORG>
+ *
+ * Fixes:
+ *		Alan Cox	:	verify_area() calls
+ *		Alan Cox	: 	stopped close while in use off icmp
+ *					messages. Not a fix but a botch that
+ *					for udp at least is 'valid'.
+ *		Alan Cox	:	Fixed icmp handling properly
+ *		Alan Cox	: 	Correct error for oversized datagrams
+ *		Alan Cox	:	Tidied select() semantics. 
+ *		Alan Cox	:	udp_err() fixed properly, also now 
+ *					select and read wake correctly on errors
+ *		Alan Cox	:	udp_send verify_area moved to avoid mem leak
+ *		Alan Cox	:	UDP can count its memory
+ *		Alan Cox	:	send to an unknown connection causes
+ *					an ECONNREFUSED off the icmp, but
+ *					does NOT close.
+ *		Alan Cox	:	Switched to new sk_buff handlers. No more backlog!
+ *		Alan Cox	:	Using generic datagram code. Even smaller and the PEEK
+ *					bug no longer crashes it.
+ *		Fred Van Kempen	: 	Net2e support for sk->broadcast.
+ *		Alan Cox	:	Uses skb_free_datagram
+ *		Alan Cox	:	Added get/set sockopt support.
+ *		Alan Cox	:	Broadcasting without option set returns EACCES.
+ *		Alan Cox	:	No wakeup calls. Instead we now use the callbacks.
+ *		Alan Cox	:	Use ip_tos and ip_ttl
+ *		Alan Cox	:	SNMP Mibs
+ *		Alan Cox	:	MSG_DONTROUTE, and 0.0.0.0 support.
+ *		Matt Dillon	:	UDP length checks.
+ *		Alan Cox	:	Smarter af_inet used properly.
+ *		Alan Cox	:	Use new kernel side addressing.
+ *		Alan Cox	:	Incorrect return on truncated datagram receive.
+ *
+ *
+ *		This program is free software; you can redistribute it and/or
+ *		modify it under the terms of the GNU General Public License
+ *		as published by the Free Software Foundation; either version
+ *		2 of the License, or (at your option) any later version.
+ */
+ 
+#include <asm/system.h>
+#include <asm/segment.h>
+#include <linux/types.h>
+#include <linux/sched.h>
+#include <linux/fcntl.h>
+#include <linux/socket.h>
+#include <linux/sockios.h>
+#include <linux/in.h>
+#include <linux/errno.h>
+#include <linux/timer.h>
+#include <linux/termios.h>
+#include <linux/mm.h>
+#include <linux/config.h>
+#include <linux/inet.h>
+#include <linux/netdevice.h>
+#include "snmp.h"
+#include "ip.h"
+#include "protocol.h"
+#include "tcp.h"
+#include <linux/skbuff.h>
+#include "sock.h"
+#include "udp.h"
+#include "icmp.h"
+#include "route.h"
+
+/*
+ *	SNMP MIB for the UDP layer
+ */
+
+struct udp_mib		udp_statistics;
+
+
+static int udp_deliver(struct sock *sk, struct udphdr *uh, struct sk_buff *skb, struct device *dev, long saddr, long daddr, int len);
+
+#define min(a,b)	((a)<(b)?(a):(b))
+
+
+/*
+ * This routine is called by the ICMP module when it gets some
+ * sort of error condition.  If err < 0 then the socket should
+ * be closed and the error returned to the user.  If err > 0
+ * it's just the icmp type << 8 | icmp code.  
+ * Header points to the ip header of the error packet. We move
+ * on past this. Then (as it used to claim before adjustment)
+ * header points to the first 8 bytes of the udp header.  We need
+ * to find the appropriate port.
+ */
+
+void udp_err(int err, unsigned char *header, unsigned long daddr,
+	unsigned long saddr, struct inet_protocol *protocol)
+{
+	struct udphdr *th;
+	struct sock *sk;
+	struct iphdr *ip=(struct iphdr *)header;
+  
+	header += 4*ip->ihl;
+
+	/*
+	 *	Find the 8 bytes of post IP header ICMP included for us
+	 */  
+	
+	th = (struct udphdr *)header;  
+   
+	sk = get_sock(&udp_prot, th->source, daddr, th->dest, saddr);
+
+	if (sk == NULL) 
+	  	return;	/* No socket for error */
+  	
+	if (err & 0xff00 ==(ICMP_SOURCE_QUENCH << 8)) 
+	{	/* Slow down! */
+		if (sk->cong_window > 1) 
+			sk->cong_window = sk->cong_window/2;
+		return;
+	}
+
+	/*
+	 *	Various people wanted BSD UDP semantics. Well they've come 
+	 *	back out because they slow down response to stuff like dead
+	 *	or unreachable name servers and they screw term users something
+	 *	chronic. Oh and it violates RFC1122. So basically fix your 
+	 *	client code people.
+	 */
+	 
+#ifdef CONFIG_I_AM_A_BROKEN_BSD_WEENIE
+	/*
+	 *	It's only fatal if we have connected to them. I'm not happy
+	 *	with this code. Some BSD comparisons need doing.
+	 */
+	 
+	if (icmp_err_convert[err & 0xff].fatal && sk->state == TCP_ESTABLISHED) 
+	{
+		sk->err = icmp_err_convert[err & 0xff].errno;
+		sk->error_report(sk);
+ 	}
+#else
+	if (icmp_err_convert[err & 0xff].fatal)
+	{
+		sk->err = icmp_err_convert[err & 0xff].errno;
+		sk->error_report(sk);
+	}
+#endif
+}
+
+
+static unsigned short udp_check(struct udphdr *uh, int len, unsigned long saddr, unsigned long daddr)
+{
+	unsigned long sum;
+
+	__asm__(  "\t addl %%ecx,%%ebx\n"
+		  "\t adcl %%edx,%%ebx\n"
+		  "\t adcl $0, %%ebx\n"
+		  : "=b"(sum)
+		  : "0"(daddr), "c"(saddr), "d"((ntohs(len) << 16) + IPPROTO_UDP*256)
+		  : "cx","bx","dx" );
+
+	if (len > 3) 
+	{
+		__asm__("\tclc\n"
+			"1:\n"
+			"\t lodsl\n"
+			"\t adcl %%eax, %%ebx\n"
+			"\t loop 1b\n"
+			"\t adcl $0, %%ebx\n"
+			: "=b"(sum) , "=S"(uh)
+			: "0"(sum), "c"(len/4) ,"1"(uh)
+			: "ax", "cx", "bx", "si" );
+	}
+
+	/*
+	 *	Convert from 32 bits to 16 bits. 
+	 */
+
+	__asm__("\t movl %%ebx, %%ecx\n"
+		"\t shrl $16,%%ecx\n"
+	  	"\t addw %%cx, %%bx\n"
+	  	"\t adcw $0, %%bx\n"
+	  	: "=b"(sum)
+	  	: "0"(sum)
+	  	: "bx", "cx");
+	
+	/* 
+	 *	Check for an extra word. 
+	 */
+	 
+	if ((len & 2) != 0) 
+	{
+		__asm__("\t lodsw\n"
+			"\t addw %%ax,%%bx\n"
+			"\t adcw $0, %%bx\n"
+			: "=b"(sum), "=S"(uh)
+			: "0"(sum) ,"1"(uh)
+			: "si", "ax", "bx");
+  	}
+
+  	/*
+  	 *	Now check for the extra byte. 
+  	 */
+  	 
+	if ((len & 1) != 0) 
+	{
+		__asm__("\t lodsb\n"
+			"\t movb $0,%%ah\n"
+			"\t addw %%ax,%%bx\n"
+			"\t adcw $0, %%bx\n"
+			: "=b"(sum)
+			: "0"(sum) ,"S"(uh)
+			: "si", "ax", "bx");
+  	}
+
+  	/* 
+  	 *	We only want the bottom 16 bits, but we never cleared the top 16. 
+  	 */
+
+	return((~sum) & 0xffff);
+}
+
+/*
+ *	Generate UDP checksums. These may be disabled, eg for fast NFS over ethernet
+ *	We default them enabled.. if you turn them off you either know what you are
+ *	doing or get burned...
+ */
+
+static void udp_send_check(struct udphdr *uh, unsigned long saddr, 
+	       unsigned long daddr, int len, struct sock *sk)
+{
+	uh->check = 0;
+	if (sk && sk->no_check) 
+	  	return;
+	uh->check = udp_check(uh, len, saddr, daddr);
+	
+	/*
+	 *	FFFF and 0 are the same, pick the right one as 0 in the
+	 *	actual field means no checksum.
+	 */
+	 
+	if (uh->check == 0)
+		uh->check = 0xffff;
+}
+
+
+static int udp_send(struct sock *sk, struct sockaddr_in *sin,
+	 unsigned char *from, int len, int rt)
+{
+	struct sk_buff *skb;
+	struct device *dev;
+	struct udphdr *uh;
+	unsigned char *buff;
+	unsigned long saddr;
+	int size, tmp;
+	int ttl;
+  
+	/* 
+	 *	Allocate an sk_buff copy of the packet.
+	 */
+	 
+	size = sk->prot->max_header + len;
+	skb = sock_alloc_send_skb(sk, size, 0, &tmp);
+
+
+	if (skb == NULL) 
+		return tmp;
+
+	skb->sk       = NULL;	/* to avoid changing sk->saddr */
+	skb->free     = 1;
+	skb->localroute = sk->localroute|(rt&MSG_DONTROUTE);
+
+	/*
+	 *	Now build the IP and MAC header. 
+	 */
+	 
+	buff = skb->data;
+	saddr = sk->saddr;
+	dev = NULL;
+	ttl = sk->ip_ttl;
+#ifdef CONFIG_IP_MULTICAST
+	if (MULTICAST(sin->sin_addr.s_addr))
+		ttl = sk->ip_mc_ttl;
+#endif
+	tmp = sk->prot->build_header(skb, saddr, sin->sin_addr.s_addr,
+			&dev, IPPROTO_UDP, sk->opt, skb->mem_len,sk->ip_tos,ttl);
+
+	skb->sk=sk;	/* So memory is freed correctly */
+	
+	/*
+	 *	Unable to put a header on the packet.
+	 */
+	 		    
+	if (tmp < 0 ) 
+	{
+		sk->prot->wfree(sk, skb->mem_addr, skb->mem_len);
+		return(tmp);
+  	}
+  	
+	buff += tmp;
+	saddr = skb->saddr; /*dev->pa_addr;*/
+	skb->len = tmp + sizeof(struct udphdr) + len;	/* len + UDP + IP + MAC */
+	skb->dev = dev;
+	
+	/*
+	 *	Fill in the UDP header. 
+	 */
+	 
+	uh = (struct udphdr *) buff;
+	uh->len = htons(len + sizeof(struct udphdr));
+	uh->source = sk->dummy_th.source;
+	uh->dest = sin->sin_port;
+	buff = (unsigned char *) (uh + 1);
+
+	/*
+	 *	Copy the user data. 
+	 */
+	 
+	memcpy_fromfs(buff, from, len);
+
+  	/*
+  	 *	Set up the UDP checksum. 
+  	 */
+  	 
+	udp_send_check(uh, saddr, sin->sin_addr.s_addr, skb->len - tmp, sk);
+
+	/* 
+	 *	Send the datagram to the interface. 
+	 */
+	 
+	udp_statistics.UdpOutDatagrams++;
+	 
+	sk->prot->queue_xmit(sk, dev, skb, 1);
+	return(len);
+}
+
+
+static int udp_sendto(struct sock *sk, unsigned char *from, int len, int noblock,
+	   unsigned flags, struct sockaddr_in *usin, int addr_len)
+{
+	struct sockaddr_in sin;
+	int tmp;
+
+	/* 
+	 *	Check the flags. We support no flags for UDP sending
+	 */
+	if (flags&~MSG_DONTROUTE) 
+	  	return(-EINVAL);
+	/*
+	 *	Get and verify the address. 
+	 */
+	 
+	if (usin) 
+	{
+		if (addr_len < sizeof(sin)) 
+			return(-EINVAL);
+		memcpy(&sin,usin,sizeof(sin));
+		if (sin.sin_family && sin.sin_family != AF_INET) 
+			return(-EINVAL);
+		if (sin.sin_port == 0) 
+			return(-EINVAL);
+	} 
+	else 
+	{
+		if (sk->state != TCP_ESTABLISHED) 
+			return(-EINVAL);
+		sin.sin_family = AF_INET;
+		sin.sin_port = sk->dummy_th.dest;
+		sin.sin_addr.s_addr = sk->daddr;
+  	}
+  
+  	/*
+  	 *	BSD socket semantics. You must set SO_BROADCAST to permit
+  	 *	broadcasting of data.
+  	 */
+  	 
+  	if(sin.sin_addr.s_addr==INADDR_ANY)
+  		sin.sin_addr.s_addr=ip_my_addr();
+  		
+  	if(!sk->broadcast && ip_chk_addr(sin.sin_addr.s_addr)==IS_BROADCAST)
+	    	return -EACCES;			/* Must turn broadcast on first */
+
+	sk->inuse = 1;
+
+	/* Send the packet. */
+	tmp = udp_send(sk, &sin, from, len, flags);
+
+	/* The datagram has been sent off.  Release the socket. */
+	release_sock(sk);
+	return(tmp);
+}
+
+/*
+ *	In BSD SOCK_DGRAM a write is just like a send.
+ */
+
+static int udp_write(struct sock *sk, unsigned char *buff, int len, int noblock,
+	  unsigned flags)
+{
+	return(udp_sendto(sk, buff, len, noblock, flags, NULL, 0));
+}
+
+
+/*
+ *	IOCTL requests applicable to the UDP protocol
+ */
+ 
+int udp_ioctl(struct sock *sk, int cmd, unsigned long arg)
+{
+	int err;
+	switch(cmd) 
+	{
+		case TIOCOUTQ:
+		{
+			unsigned long amount;
+
+			if (sk->state == TCP_LISTEN) return(-EINVAL);
+			amount = sk->prot->wspace(sk)/*/2*/;
+			err=verify_area(VERIFY_WRITE,(void *)arg,
+					sizeof(unsigned long));
+			if(err)
+				return(err);
+			put_fs_long(amount,(unsigned long *)arg);
+			return(0);
+		}
+
+		case TIOCINQ:
+		{
+			struct sk_buff *skb;
+			unsigned long amount;
+
+			if (sk->state == TCP_LISTEN) return(-EINVAL);
+			amount = 0;
+			skb = skb_peek(&sk->receive_queue);
+			if (skb != NULL) {
+				/*
+				 * We will only return the amount
+				 * of this packet since that is all
+				 * that will be read.
+				 */
+				amount = skb->len;
+			}
+			err=verify_area(VERIFY_WRITE,(void *)arg,
+						sizeof(unsigned long));
+			if(err)
+				return(err);
+			put_fs_long(amount,(unsigned long *)arg);
+			return(0);
+		}
+
+		default:
+			return(-EINVAL);
+	}
+	return(0);
+}
+
+
+/*
+ * 	This should be easy, if there is something there we\
+ * 	return it, otherwise we block.
+ */
+
+int udp_recvfrom(struct sock *sk, unsigned char *to, int len,
+	     int noblock, unsigned flags, struct sockaddr_in *sin,
+	     int *addr_len)
+{
+  	int copied = 0;
+  	int truesize;
+  	struct sk_buff *skb;
+  	int er;
+
+	/*
+	 *	Check any passed addresses
+	 */
+	 
+  	if (addr_len) 
+  		*addr_len=sizeof(*sin);
+  
+	/*
+	 *	From here the generic datagram does a lot of the work. Come
+	 *	the finished NET3, it will do _ALL_ the work!
+	 */
+	 	
+	skb=skb_recv_datagram(sk,flags,noblock,&er);
+	if(skb==NULL)
+  		return er;
+  
+  	truesize = skb->len;
+  	copied = min(len, truesize);
+
+  	/*
+  	 *	FIXME : should use udp header size info value 
+  	 */
+  	 
+	skb_copy_datagram(skb,sizeof(struct udphdr),to,copied);
+	sk->stamp=skb->stamp;
+
+	/* Copy the address. */
+	if (sin) 
+	{
+		sin->sin_family = AF_INET;
+		sin->sin_port = skb->h.uh->source;
+		sin->sin_addr.s_addr = skb->daddr;
+  	}
+  
+  	skb_free_datagram(skb);
+  	release_sock(sk);
+  	return(truesize);
+}
+
+/*
+ *	Read has the same semantics as recv in SOCK_DGRAM
+ */
+
+int udp_read(struct sock *sk, unsigned char *buff, int len, int noblock,
+	 unsigned flags)
+{
+	return(udp_recvfrom(sk, buff, len, noblock, flags, NULL, NULL));
+}
+
+
+int udp_connect(struct sock *sk, struct sockaddr_in *usin, int addr_len)
+{
+	struct rtable *rt;
+	unsigned long sa;
+	if (addr_len < sizeof(*usin)) 
+	  	return(-EINVAL);
+
+	if (usin->sin_family && usin->sin_family != AF_INET) 
+	  	return(-EAFNOSUPPORT);
+	if (usin->sin_addr.s_addr==INADDR_ANY)
+		usin->sin_addr.s_addr=ip_my_addr();
+
+	if(!sk->broadcast && ip_chk_addr(usin->sin_addr.s_addr)==IS_BROADCAST)
+		return -EACCES;			/* Must turn broadcast on first */
+  	
+  	rt=ip_rt_route(usin->sin_addr.s_addr, NULL, &sa);
+  	if(rt==NULL)
+  		return -ENETUNREACH;
+  	sk->saddr = sa;		/* Update source address */
+	sk->daddr = usin->sin_addr.s_addr;
+	sk->dummy_th.dest = usin->sin_port;
+	sk->state = TCP_ESTABLISHED;
+	return(0);
+}
+
+
+static void udp_close(struct sock *sk, int timeout)
+{
+	sk->inuse = 1;
+	sk->state = TCP_CLOSE;
+	if (sk->dead) 
+		destroy_sock(sk);
+	else
+		release_sock(sk);
+}
+
+
+/*
+ *	All we need to do is get the socket, and then do a checksum. 
+ */
+ 
+int udp_rcv(struct sk_buff *skb, struct device *dev, struct options *opt,
+	unsigned long daddr, unsigned short len,
+	unsigned long saddr, int redo, struct inet_protocol *protocol)
+{
+  	struct sock *sk;
+  	struct udphdr *uh;
+	unsigned short ulen;
+	int addr_type = IS_MYADDR;
+	
+	if(!dev || dev->pa_addr!=daddr)
+		addr_type=ip_chk_addr(daddr);
+		
+	/*
+	 *	Get the header.
+	 */
+  	uh = (struct udphdr *) skb->h.uh;
+  	
+  	ip_statistics.IpInDelivers++;
+
+	/*
+	 *	Validate the packet and the UDP length.
+	 */
+	 
+	ulen = ntohs(uh->len);
+
+	if (ulen > len || len < sizeof(*uh) || ulen < sizeof(*uh)) 
+	{
+		printk("UDP: short packet: %d/%d\n", ulen, len);
+		udp_statistics.UdpInErrors++;
+		kfree_skb(skb, FREE_WRITE);
+		return(0);
+	}
+
+	if (uh->check && udp_check(uh, len, saddr, daddr)) 
+	{
+		/* <mea@utu.fi> wants to know, who sent it, to
+		   go and stomp on the garbage sender... */
+		printk("UDP: bad checksum. From %08lX:%d to %08lX:%d ulen %d\n",
+		       ntohl(saddr),ntohs(uh->source),
+		       ntohl(daddr),ntohs(uh->dest),
+		       ulen);
+		udp_statistics.UdpInErrors++;
+		kfree_skb(skb, FREE_WRITE);
+		return(0);
+	}
+
+
+	len=ulen;
+
+#ifdef CONFIG_IP_MULTICAST
+	if (addr_type!=IS_MYADDR)
+	{
+		/*
+		 *	Multicasts and broadcasts go to each listener.
+		 */
+		struct sock *sknext=NULL;
+		sk=get_sock_mcast(udp_prot.sock_array[ntohs(uh->dest)&(SOCK_ARRAY_SIZE-1)], uh->dest,
+				saddr, uh->source, daddr);
+		if(sk)
+		{		
+			do
+			{
+				struct sk_buff *skb1;
+
+				sknext=get_sock_mcast(sk->next, uh->dest, saddr, uh->source, daddr);
+				if(sknext)
+					skb1=skb_clone(skb,GFP_ATOMIC);
+				else
+					skb1=skb;
+				if(skb1)
+					udp_deliver(sk, uh, skb1, dev,saddr,daddr,len);
+				sk=sknext;
+			}
+			while(sknext!=NULL);
+		}
+		else
+			kfree_skb(skb, FREE_READ);
+		return 0;
+	}	
+#endif
+  	sk = get_sock(&udp_prot, uh->dest, saddr, uh->source, daddr);
+	if (sk == NULL) 
+  	{
+  		udp_statistics.UdpNoPorts++;
+		if (addr_type == IS_MYADDR) 
+		{
+			icmp_send(skb, ICMP_DEST_UNREACH, ICMP_PORT_UNREACH, 0, dev);
+		}
+		/*
+		 * Hmm.  We got an UDP broadcast to a port to which we
+		 * don't wanna listen.  Ignore it.
+		 */
+		skb->sk = NULL;
+		kfree_skb(skb, FREE_WRITE);
+		return(0);
+  	}
+
+	return udp_deliver(sk,uh,skb,dev, saddr, daddr, len);
+}
+
+static int udp_deliver(struct sock *sk, struct udphdr *uh, struct sk_buff *skb, struct device *dev, long saddr, long daddr, int len)
+{
+	skb->sk = sk;
+	skb->dev = dev;
+	skb->len = len;
+
+	/*
+	 *	These are supposed to be switched. 
+	 */
+	 
+	skb->daddr = saddr;
+	skb->saddr = daddr;
+
+
+	/*
+	 *	Charge it to the socket, dropping if the queue is full.
+	 */
+
+	skb->len = len - sizeof(*uh);  
+	 
+	if (sock_queue_rcv_skb(sk,skb)<0) 
+	{
+		udp_statistics.UdpInErrors++;
+		ip_statistics.IpInDiscards++;
+		ip_statistics.IpInDelivers--;
+		skb->sk = NULL;
+		kfree_skb(skb, FREE_WRITE);
+		release_sock(sk);
+		return(0);
+	}
+  	udp_statistics.UdpInDatagrams++;
+	release_sock(sk);
+	return(0);
+}
+
+
+struct proto udp_prot = {
+	sock_wmalloc,
+	sock_rmalloc,
+	sock_wfree,
+	sock_rfree,
+	sock_rspace,
+	sock_wspace,
+	udp_close,
+	udp_read,
+	udp_write,
+	udp_sendto,
+	udp_recvfrom,
+	ip_build_header,
+	udp_connect,
+	NULL,
+	ip_queue_xmit,
+	NULL,
+	NULL,
+	NULL,
+	udp_rcv,
+	datagram_select,
+	udp_ioctl,
+	NULL,
+	NULL,
+	ip_setsockopt,
+	ip_getsockopt,
+	128,
+	0,
+	{NULL,},
+	"UDP",
+	0, 0
+};
+