Import sources from 2011-03-30 iso image

1 files changed, 299 insertions, 0 deletions

diff --git a/sys/src/9/ip/igmp.c b/sys/src/9/ip/igmp.c
new file mode 100755
index 000000000..c0c330fac
--- /dev/null
+++ b/sys/src/9/ip/igmp.c
@@ -0,0 +1,299 @@
+/*
+ * igmp - internet group management protocol
+ * unfinished.
+ */
+#include "u.h"
+#include "../port/lib.h"
+#include "mem.h"
+#include "dat.h"
+#include "fns.h"
+#include "../port/error.h"
+
+#include "ip.h"
+
+enum
+{
+	IGMP_IPHDRSIZE	= 20,		/* size of ip header */
+	IGMP_HDRSIZE	= 8,		/* size of IGMP header */
+	IP_IGMPPROTO	= 2,
+
+	IGMPquery	= 1,
+	IGMPreport	= 2,
+
+	MSPTICK		= 100,
+	MAXTIMEOUT	= 10000/MSPTICK,	/* at most 10 secs for a response */
+};
+
+typedef struct IGMPpkt IGMPpkt;
+struct IGMPpkt
+{
+	/* ip header */
+	uchar	vihl;		/* Version and header length */
+	uchar	tos;		/* Type of service */
+	uchar	len[2];		/* packet length (including headers) */
+	uchar	id[2];		/* Identification */
+	uchar	frag[2];	/* Fragment information */
+	uchar	Unused;	
+	uchar	proto;		/* Protocol */
+	uchar	cksum[2];	/* checksum of ip portion */
+	uchar	src[IPaddrlen];		/* Ip source */
+	uchar	dst[IPaddrlen];		/* Ip destination */
+
+	/* igmp header */
+	uchar	vertype;	/* version and type */
+	uchar	unused;
+	uchar	igmpcksum[2];		/* checksum of igmp portion */
+	uchar	group[IPaddrlen];	/* multicast group */
+
+	uchar	payload[];
+};
+
+#define IGMPPKTSZ offsetof(IGMPpkt, payload[0])
+
+/*
+ *  lists for group reports
+ */
+typedef struct IGMPrep IGMPrep;
+struct IGMPrep
+{
+	IGMPrep		*next;
+	Medium		*m;
+	int		ticks;
+	Multicast	*multi;
+};
+
+typedef struct IGMP IGMP;
+struct IGMP
+{
+	Lock;
+	Rendez	r;
+	IGMPrep	*reports;
+};
+
+IGMP igmpalloc;
+
+	Proto	igmp;
+extern	Fs	fs;
+
+static struct Stats
+{
+	ulong 	inqueries;
+	ulong	outqueries;
+	ulong	inreports;
+	ulong	outreports;
+} stats;
+
+void
+igmpsendreport(Medium *m, uchar *addr)
+{
+	IGMPpkt *p;
+	Block *bp;
+
+	bp = allocb(sizeof(IGMPpkt));
+	if(bp == nil)
+		return;
+	p = (IGMPpkt*)bp->wp;
+	p->vihl = IP_VER4;
+	bp->wp += IGMPPKTSZ;
+	memset(bp->rp, 0, IGMPPKTSZ);
+	hnputl(p->src, Mediumgetaddr(m));
+	hnputl(p->dst, Ipallsys);
+	p->vertype = (1<<4) | IGMPreport;
+	p->proto = IP_IGMPPROTO;
+	memmove(p->group, addr, IPaddrlen);
+	hnputs(p->igmpcksum, ptclcsum(bp, IGMP_IPHDRSIZE, IGMP_HDRSIZE));
+	netlog(Logigmp, "igmpreport %I\n", p->group);
+	stats.outreports++;
+	ipoput4(bp, 0, 1, DFLTTOS, nil);	/* TTL of 1 */
+}
+
+static int
+isreport(void *a)
+{
+	USED(a);
+	return igmpalloc.reports != 0;
+}
+
+
+void
+igmpproc(void *a)
+{
+	IGMPrep *rp, **lrp;
+	Multicast *mp, **lmp;
+	uchar ip[IPaddrlen];
+
+	USED(a);
+
+	for(;;){
+		sleep(&igmpalloc.r, isreport, 0);
+		for(;;){
+			lock(&igmpalloc);
+
+			if(igmpalloc.reports == nil)
+				break;
+	
+			/* look for a single report */
+			lrp = &igmpalloc.reports;
+			mp = nil;
+			for(rp = *lrp; rp; rp = *lrp){
+				rp->ticks++;
+				lmp = &rp->multi;
+				for(mp = *lmp; mp; mp = *lmp){
+					if(rp->ticks >= mp->timeout){
+						*lmp = mp->next;
+						break;
+					}
+					lmp = &mp->next;
+				}
+				if(mp != nil)
+					break;
+
+				if(rp->multi != nil){
+					lrp = &rp->next;
+					continue;
+				} else {
+					*lrp = rp->next;
+					free(rp);
+				}
+			}
+			unlock(&igmpalloc);
+
+			if(mp){
+				/* do a single report and try again */
+				hnputl(ip, mp->addr);
+				igmpsendreport(rp->m, ip);
+				free(mp);
+				continue;
+			}
+
+			tsleep(&up->sleep, return0, 0, MSPTICK);
+		}
+		unlock(&igmpalloc);
+	}
+
+}
+
+void
+igmpiput(Medium *m, Ipifc *, Block *bp)
+{
+	int n;
+	IGMPpkt *ghp;
+	Ipaddr group;
+	IGMPrep *rp, **lrp;
+	Multicast *mp, **lmp;
+
+	ghp = (IGMPpkt*)(bp->rp);
+	netlog(Logigmp, "igmpiput: %d %I\n", ghp->vertype, ghp->group);
+
+	n = blocklen(bp);
+	if(n < IGMP_IPHDRSIZE+IGMP_HDRSIZE){
+		netlog(Logigmp, "igmpiput: bad len\n");
+		goto error;
+	}
+	if((ghp->vertype>>4) != 1){
+		netlog(Logigmp, "igmpiput: bad igmp type\n");
+		goto error;
+	}
+	if(ptclcsum(bp, IGMP_IPHDRSIZE, IGMP_HDRSIZE)){
+		netlog(Logigmp, "igmpiput: checksum error %I\n", ghp->src);
+		goto error;
+	}
+
+	group = nhgetl(ghp->group);
+	
+	lock(&igmpalloc);
+	switch(ghp->vertype & 0xf){
+	case IGMPquery:
+		/*
+		 *  start reporting groups that we're a member of.
+		 */
+		stats.inqueries++;
+		for(rp = igmpalloc.reports; rp; rp = rp->next)
+			if(rp->m == m)
+				break;
+		if(rp != nil)
+			break;	/* already reporting */
+
+		mp = Mediumcopymulti(m);
+		if(mp == nil)
+			break;
+
+		rp = malloc(sizeof(*rp));
+		if(rp == nil)
+			break;
+
+		rp->m = m;
+		rp->multi = mp;
+		rp->ticks = 0;
+		for(; mp; mp = mp->next)
+			mp->timeout = nrand(MAXTIMEOUT);
+		rp->next = igmpalloc.reports;
+		igmpalloc.reports = rp;
+
+		wakeup(&igmpalloc.r);
+
+		break;
+	case IGMPreport:
+		/*
+		 *  find report list for this medium
+		 */
+		stats.inreports++;
+		lrp = &igmpalloc.reports;
+		for(rp = *lrp; rp; rp = *lrp){
+			if(rp->m == m)
+				break;
+			lrp = &rp->next;
+		}
+		if(rp == nil)
+			break;
+
+		/*
+		 *  if someone else has reported a group,
+		 *  we don't have to.
+		 */
+		lmp = &rp->multi;
+		for(mp = *lmp; mp; mp = *lmp){
+			if(mp->addr == group){
+				*lmp = mp->next;
+				free(mp);
+				break;
+			}
+			lmp = &mp->next;
+		}
+
+		break;
+	}
+	unlock(&igmpalloc);
+
+error:
+	freeb(bp);
+}
+
+int
+igmpstats(char *buf, int len)
+{
+	return snprint(buf, len, "\trcvd %d %d\n\tsent %d %d\n",
+		stats.inqueries, stats.inreports,
+		stats.outqueries, stats.outreports);
+}
+
+void
+igmpinit(Fs *fs)
+{
+	igmp.name = "igmp";
+	igmp.connect = nil;
+	igmp.announce = nil;
+	igmp.ctl = nil;
+	igmp.state = nil;
+	igmp.close = nil;
+	igmp.rcv = igmpiput;
+	igmp.stats = igmpstats;
+	igmp.ipproto = IP_IGMPPROTO;
+	igmp.nc = 0;
+	igmp.ptclsize = 0;
+
+	igmpreportfn = igmpsendreport;
+	kproc("igmpproc", igmpproc, 0);
+
+	Fsproto(fs, &igmp);
+}