Import sources from 2011-03-30 iso image

1 files changed, 492 insertions, 0 deletions

diff --git a/sys/src/9/ip/icmp.c b/sys/src/9/ip/icmp.c
new file mode 100755
index 000000000..9dd5c9414
--- /dev/null
+++ b/sys/src/9/ip/icmp.c
@@ -0,0 +1,492 @@
+#include "u.h"
+#include "../port/lib.h"
+#include "mem.h"
+#include "dat.h"
+#include "fns.h"
+#include "../port/error.h"
+
+#include "ip.h"
+
+typedef struct Icmp {
+	uchar	vihl;		/* Version and header length */
+	uchar	tos;		/* Type of service */
+	uchar	length[2];	/* packet length */
+	uchar	id[2];		/* Identification */
+	uchar	frag[2];	/* Fragment information */
+	uchar	ttl;		/* Time to live */
+	uchar	proto;		/* Protocol */
+	uchar	ipcksum[2];	/* Header checksum */
+	uchar	src[4];		/* Ip source */
+	uchar	dst[4];		/* Ip destination */
+	uchar	type;
+	uchar	code;
+	uchar	cksum[2];
+	uchar	icmpid[2];
+	uchar	seq[2];
+	uchar	data[1];
+} Icmp;
+
+enum {			/* Packet Types */
+	EchoReply	= 0,
+	Unreachable	= 3,
+	SrcQuench	= 4,
+	Redirect	= 5,
+	EchoRequest	= 8,
+	TimeExceed	= 11,
+	InParmProblem	= 12,
+	Timestamp	= 13,
+	TimestampReply	= 14,
+	InfoRequest	= 15,
+	InfoReply	= 16,
+	AddrMaskRequest = 17,
+	AddrMaskReply   = 18,
+
+	Maxtype		= 18,
+};
+
+enum
+{
+	MinAdvise	= 24,	/* minimum needed for us to advise another protocol */ 
+};
+
+char *icmpnames[Maxtype+1] =
+{
+[EchoReply]		"EchoReply",
+[Unreachable]		"Unreachable",
+[SrcQuench]		"SrcQuench",
+[Redirect]		"Redirect",
+[EchoRequest]		"EchoRequest",
+[TimeExceed]		"TimeExceed",
+[InParmProblem]		"InParmProblem",
+[Timestamp]		"Timestamp",
+[TimestampReply]	"TimestampReply",
+[InfoRequest]		"InfoRequest",
+[InfoReply]		"InfoReply",
+[AddrMaskRequest]	"AddrMaskRequest",
+[AddrMaskReply  ]	"AddrMaskReply  ",
+};
+
+enum {
+	IP_ICMPPROTO	= 1,
+	ICMP_IPSIZE	= 20,
+	ICMP_HDRSIZE	= 8,
+};
+
+enum
+{
+	InMsgs,
+	InErrors,
+	OutMsgs,
+	CsumErrs,
+	LenErrs,
+	HlenErrs,
+
+	Nstats,
+};
+
+static char *statnames[Nstats] =
+{
+[InMsgs]	"InMsgs",
+[InErrors]	"InErrors",
+[OutMsgs]	"OutMsgs",
+[CsumErrs]	"CsumErrs",
+[LenErrs]	"LenErrs",
+[HlenErrs]	"HlenErrs",
+};
+
+typedef struct Icmppriv Icmppriv;
+struct Icmppriv
+{
+	ulong	stats[Nstats];
+
+	/* message counts */
+	ulong	in[Maxtype+1];
+	ulong	out[Maxtype+1];
+};
+
+static void icmpkick(void *x, Block*);
+
+static void
+icmpcreate(Conv *c)
+{
+	c->rq = qopen(64*1024, Qmsg, 0, c);
+	c->wq = qbypass(icmpkick, c);
+}
+
+extern char*
+icmpconnect(Conv *c, char **argv, int argc)
+{
+	char *e;
+
+	e = Fsstdconnect(c, argv, argc);
+	if(e != nil)
+		return e;
+	Fsconnected(c, e);
+
+	return nil;
+}
+
+extern int
+icmpstate(Conv *c, char *state, int n)
+{
+	USED(c);
+	return snprint(state, n, "%s qin %d qout %d\n",
+		"Datagram",
+		c->rq ? qlen(c->rq) : 0,
+		c->wq ? qlen(c->wq) : 0
+	);
+}
+
+extern char*
+icmpannounce(Conv *c, char **argv, int argc)
+{
+	char *e;
+
+	e = Fsstdannounce(c, argv, argc);
+	if(e != nil)
+		return e;
+	Fsconnected(c, nil);
+
+	return nil;
+}
+
+extern void
+icmpclose(Conv *c)
+{
+	qclose(c->rq);
+	qclose(c->wq);
+	ipmove(c->laddr, IPnoaddr);
+	ipmove(c->raddr, IPnoaddr);
+	c->lport = 0;
+}
+
+static void
+icmpkick(void *x, Block *bp)
+{
+	Conv *c = x;
+	Icmp *p;
+	Icmppriv *ipriv;
+
+	if(bp == nil)
+		return;
+
+	if(blocklen(bp) < ICMP_IPSIZE + ICMP_HDRSIZE){
+		freeblist(bp);
+		return;
+	}
+	p = (Icmp *)(bp->rp);
+	p->vihl = IP_VER4;
+	ipriv = c->p->priv;
+	if(p->type <= Maxtype)	
+		ipriv->out[p->type]++;
+	
+	v6tov4(p->dst, c->raddr);
+	v6tov4(p->src, c->laddr);
+	p->proto = IP_ICMPPROTO;
+	hnputs(p->icmpid, c->lport);
+	memset(p->cksum, 0, sizeof(p->cksum));
+	hnputs(p->cksum, ptclcsum(bp, ICMP_IPSIZE, blocklen(bp) - ICMP_IPSIZE));
+	ipriv->stats[OutMsgs]++;
+	ipoput4(c->p->f, bp, 0, c->ttl, c->tos, nil);
+}
+
+extern void
+icmpttlexceeded(Fs *f, uchar *ia, Block *bp)
+{
+	Block	*nbp;
+	Icmp	*p, *np;
+
+	p = (Icmp *)bp->rp;
+
+	netlog(f, Logicmp, "sending icmpttlexceeded -> %V\n", p->src);
+	nbp = allocb(ICMP_IPSIZE + ICMP_HDRSIZE + ICMP_IPSIZE + 8);
+	nbp->wp += ICMP_IPSIZE + ICMP_HDRSIZE + ICMP_IPSIZE + 8;
+	np = (Icmp *)nbp->rp;
+	np->vihl = IP_VER4;
+	memmove(np->dst, p->src, sizeof(np->dst));
+	v6tov4(np->src, ia);
+	memmove(np->data, bp->rp, ICMP_IPSIZE + 8);
+	np->type = TimeExceed;
+	np->code = 0;
+	np->proto = IP_ICMPPROTO;
+	hnputs(np->icmpid, 0);
+	hnputs(np->seq, 0);
+	memset(np->cksum, 0, sizeof(np->cksum));
+	hnputs(np->cksum, ptclcsum(nbp, ICMP_IPSIZE, blocklen(nbp) - ICMP_IPSIZE));
+	ipoput4(f, nbp, 0, MAXTTL, DFLTTOS, nil);
+
+}
+
+static void
+icmpunreachable(Fs *f, Block *bp, int code, int seq)
+{
+	Block	*nbp;
+	Icmp	*p, *np;
+	int	i;
+	uchar	addr[IPaddrlen];
+
+	p = (Icmp *)bp->rp;
+
+	/* only do this for unicast sources and destinations */
+	v4tov6(addr, p->dst);
+	i = ipforme(f, addr);
+	if((i&Runi) == 0)
+		return;
+	v4tov6(addr, p->src);
+	i = ipforme(f, addr);
+	if(i != 0 && (i&Runi) == 0)
+		return;
+
+	netlog(f, Logicmp, "sending icmpnoconv -> %V\n", p->src);
+	nbp = allocb(ICMP_IPSIZE + ICMP_HDRSIZE + ICMP_IPSIZE + 8);
+	nbp->wp += ICMP_IPSIZE + ICMP_HDRSIZE + ICMP_IPSIZE + 8;
+	np = (Icmp *)nbp->rp;
+	np->vihl = IP_VER4;
+	memmove(np->dst, p->src, sizeof(np->dst));
+	memmove(np->src, p->dst, sizeof(np->src));
+	memmove(np->data, bp->rp, ICMP_IPSIZE + 8);
+	np->type = Unreachable;
+	np->code = code;
+	np->proto = IP_ICMPPROTO;
+	hnputs(np->icmpid, 0);
+	hnputs(np->seq, seq);
+	memset(np->cksum, 0, sizeof(np->cksum));
+	hnputs(np->cksum, ptclcsum(nbp, ICMP_IPSIZE, blocklen(nbp) - ICMP_IPSIZE));
+	ipoput4(f, nbp, 0, MAXTTL, DFLTTOS, nil);
+}
+
+extern void
+icmpnoconv(Fs *f, Block *bp)
+{
+	icmpunreachable(f, bp, 3, 0);
+}
+
+extern void
+icmpcantfrag(Fs *f, Block *bp, int mtu)
+{
+	icmpunreachable(f, bp, 4, mtu);
+}
+
+static void
+goticmpkt(Proto *icmp, Block *bp)
+{
+	Conv	**c, *s;
+	Icmp	*p;
+	uchar	dst[IPaddrlen];
+	ushort	recid;
+
+	p = (Icmp *) bp->rp;
+	v4tov6(dst, p->src);
+	recid = nhgets(p->icmpid);
+
+	for(c = icmp->conv; *c; c++) {
+		s = *c;
+		if(s->lport == recid)
+		if(ipcmp(s->raddr, dst) == 0){
+			bp = concatblock(bp);
+			if(bp != nil)
+				qpass(s->rq, bp);
+			return;
+		}
+	}
+	freeblist(bp);
+}
+
+static Block *
+mkechoreply(Block *bp)
+{
+	Icmp	*q;
+	uchar	ip[4];
+
+	q = (Icmp *)bp->rp;
+	q->vihl = IP_VER4;
+	memmove(ip, q->src, sizeof(q->dst));
+	memmove(q->src, q->dst, sizeof(q->src));
+	memmove(q->dst, ip,  sizeof(q->dst));
+	q->type = EchoReply;
+	memset(q->cksum, 0, sizeof(q->cksum));
+	hnputs(q->cksum, ptclcsum(bp, ICMP_IPSIZE, blocklen(bp) - ICMP_IPSIZE));
+
+	return bp;
+}
+
+static char *unreachcode[] =
+{
+[0]	"net unreachable",
+[1]	"host unreachable",
+[2]	"protocol unreachable",
+[3]	"port unreachable",
+[4]	"fragmentation needed and DF set",
+[5]	"source route failed",
+};
+
+static void
+icmpiput(Proto *icmp, Ipifc*, Block *bp)
+{
+	int	n, iplen;
+	Icmp	*p;
+	Block	*r;
+	Proto	*pr;
+	char	*msg;
+	char	m2[128];
+	Icmppriv *ipriv;
+
+	ipriv = icmp->priv;
+	
+	ipriv->stats[InMsgs]++;
+
+	p = (Icmp *)bp->rp;
+	netlog(icmp->f, Logicmp, "icmpiput %s (%d) %d\n",
+		(p->type < nelem(icmpnames)? icmpnames[p->type]: ""),
+		p->type, p->code);
+	n = blocklen(bp);
+	if(n < ICMP_IPSIZE+ICMP_HDRSIZE){
+		ipriv->stats[InErrors]++;
+		ipriv->stats[HlenErrs]++;
+		netlog(icmp->f, Logicmp, "icmp hlen %d\n", n);
+		goto raise;
+	}
+	iplen = nhgets(p->length);
+	if(iplen > n){
+		ipriv->stats[LenErrs]++;
+		ipriv->stats[InErrors]++;
+		netlog(icmp->f, Logicmp, "icmp length %d\n", iplen);
+		goto raise;
+	}
+	if(ptclcsum(bp, ICMP_IPSIZE, iplen - ICMP_IPSIZE)){
+		ipriv->stats[InErrors]++;
+		ipriv->stats[CsumErrs]++;
+		netlog(icmp->f, Logicmp, "icmp checksum error\n");
+		goto raise;
+	}
+	if(p->type <= Maxtype)
+		ipriv->in[p->type]++;
+
+	switch(p->type) {
+	case EchoRequest:
+		if (iplen < n)
+			bp = trimblock(bp, 0, iplen);
+		r = mkechoreply(bp);
+		ipriv->out[EchoReply]++;
+		ipoput4(icmp->f, r, 0, MAXTTL, DFLTTOS, nil);
+		break;
+	case Unreachable:
+		if(p->code > 5)
+			msg = unreachcode[1];
+		else
+			msg = unreachcode[p->code];
+
+		bp->rp += ICMP_IPSIZE+ICMP_HDRSIZE;
+		if(blocklen(bp) < MinAdvise){
+			ipriv->stats[LenErrs]++;
+			goto raise;
+		}
+		p = (Icmp *)bp->rp;
+		pr = Fsrcvpcolx(icmp->f, p->proto);
+		if(pr != nil && pr->advise != nil) {
+			(*pr->advise)(pr, bp, msg);
+			return;
+		}
+
+		bp->rp -= ICMP_IPSIZE+ICMP_HDRSIZE;
+		goticmpkt(icmp, bp);
+		break;
+	case TimeExceed:
+		if(p->code == 0){
+			sprint(m2, "ttl exceeded at %V", p->src);
+
+			bp->rp += ICMP_IPSIZE+ICMP_HDRSIZE;
+			if(blocklen(bp) < MinAdvise){
+				ipriv->stats[LenErrs]++;
+				goto raise;
+			}
+			p = (Icmp *)bp->rp;
+			pr = Fsrcvpcolx(icmp->f, p->proto);
+			if(pr != nil && pr->advise != nil) {
+				(*pr->advise)(pr, bp, m2);
+				return;
+			}
+			bp->rp -= ICMP_IPSIZE+ICMP_HDRSIZE;
+		}
+
+		goticmpkt(icmp, bp);
+		break;
+	default:
+		goticmpkt(icmp, bp);
+		break;
+	}
+	return;
+
+raise:
+	freeblist(bp);
+}
+
+void
+icmpadvise(Proto *icmp, Block *bp, char *msg)
+{
+	Conv	**c, *s;
+	Icmp	*p;
+	uchar	dst[IPaddrlen];
+	ushort	recid;
+
+	p = (Icmp *) bp->rp;
+	v4tov6(dst, p->dst);
+	recid = nhgets(p->icmpid);
+
+	for(c = icmp->conv; *c; c++) {
+		s = *c;
+		if(s->lport == recid)
+		if(ipcmp(s->raddr, dst) == 0){
+			qhangup(s->rq, msg);
+			qhangup(s->wq, msg);
+			break;
+		}
+	}
+	freeblist(bp);
+}
+
+int
+icmpstats(Proto *icmp, char *buf, int len)
+{
+	Icmppriv *priv;
+	char *p, *e;
+	int i;
+
+	priv = icmp->priv;
+	p = buf;
+	e = p+len;
+	for(i = 0; i < Nstats; i++)
+		p = seprint(p, e, "%s: %lud\n", statnames[i], priv->stats[i]);
+	for(i = 0; i <= Maxtype; i++){
+		if(icmpnames[i])
+			p = seprint(p, e, "%s: %lud %lud\n", icmpnames[i], priv->in[i], priv->out[i]);
+		else
+			p = seprint(p, e, "%d: %lud %lud\n", i, priv->in[i], priv->out[i]);
+	}
+	return p - buf;
+}
+	
+void
+icmpinit(Fs *fs)
+{
+	Proto *icmp;
+
+	icmp = smalloc(sizeof(Proto));
+	icmp->priv = smalloc(sizeof(Icmppriv));
+	icmp->name = "icmp";
+	icmp->connect = icmpconnect;
+	icmp->announce = icmpannounce;
+	icmp->state = icmpstate;
+	icmp->create = icmpcreate;
+	icmp->close = icmpclose;
+	icmp->rcv = icmpiput;
+	icmp->stats = icmpstats;
+	icmp->ctl = nil;
+	icmp->advise = icmpadvise;
+	icmp->gc = nil;
+	icmp->ipproto = IP_ICMPPROTO;
+	icmp->nc = 128;
+	icmp->ptclsize = 0;
+
+	Fsproto(fs, icmp);
+}