From b7ea96cf198d50dd3ca528b2fd280f74e1b72015 Mon Sep 17 00:00:00 2001
From: David du Colombier <0intro@gmail.com>
Date: Fri, 29 May 1992 00:00:00 +0000
Subject: [PATCH] Plan 9 from Bell Labs 1992-05-29

---
 pc/devvga.c   |  20 +---------
 port/devip.c  | 100 ++++++++++++++++++++++++++++++++++++++++++++++++++
 port/stream.c |   4 +-
 port/tcpif.c  |   1 +
 4 files changed, 104 insertions(+), 21 deletions(-)

diff --git a/pc/devvga.c b/pc/devvga.c
index 64f6f239094aa07a8787afd3702f8bb8d3c45c1c..db1b1906120fda94d47f4c3cba9d89ea998fec4f 100644
--- a/pc/devvga.c
+++ b/pc/devvga.c
@@ -27,8 +27,7 @@ enum {
 	Qvgasize=	2,
 	Qvgatype=	3,
 	Qvgaport=	4,
-	Qvgaiport=	5,
-	Nvga=		5,
+	Nvga=		4,
 };
 
 Dirtab vgadir[]={
@@ -36,7 +35,6 @@ Dirtab vgadir[]={
 	"vgatype",	{Qvgatype},	0,		0666,
 	"vgasize",	{Qvgasize},	0,		0666,
 	"vgaport",	{Qvgaport},	0,		0666,
-	"vgaiport",	{Qvgaiport},	0,		0666,
 };
 
 /* a routine from ../port/devcons.c */
@@ -141,8 +139,6 @@ vgaread(Chan *c, void *buf, long n, ulong offset)
 		for (port=offset; port<offset+n; port++)
 			*cp++ = inb(port);
 		return n;
-	case Qvgaiport:
-		error(Eio);
 	}
 }
 
@@ -174,20 +170,6 @@ vgawrite(Chan *c, void *buf, long n, ulong offset)
 		for (port=offset; port<offset+n; port++)
 			outb(port, *cp++);
 		return n;
-	case Qvgaiport:
-		port = offset / 256;
-		switch (port) {
-		case EMISCW:	outfunc = genout;	break;
-		case SRX:	outfunc = srout;	break;
-		case GRX:	outfunc = grout;	break;
-		case ARW:	outfunc = arout;	break;
-		case CRX:	outfunc = crout;	break;
-		default:
-			error(Ebadarg);
-		}
-		for (i = offset%256; i < (offset%256) + n; i++)
-			outfunc(i, *cp++);
-		return n;
 	}
 }
 
diff --git a/port/devip.c b/port/devip.c
index e45665bacfa4594255fedd04640d676e82044d30..cfec8649029ee0eb88a55d40c181c7a1dff2d9f3 100644
--- a/port/devip.c
+++ b/port/devip.c
@@ -38,10 +38,16 @@ void	iliput(Queue *, Block *);
 void	iloput(Queue *, Block *);
 void	ilopen(Queue *, Stream *);
 void	ilclose(Queue *);
+/* BSD authentication Protocol checker */
+void	bsdiput(Queue *, Block *);
+void	bsdoput(Queue *, Block *);
+void	bsdopen(Queue *, Stream *);
+void	bsdclose(Queue *);
 
 Qinfo tcpinfo = { tcpstiput, tcpstoput, tcpstopen, tcpstclose, "tcp", 0, 1 };
 Qinfo udpinfo = { udpstiput, udpstoput, udpstopen, udpstclose, "udp" };
 Qinfo ilinfo  = { iliput,    iloput,    ilopen,    ilclose,    "il"  };
+Qinfo bsdinfo = { bsdiput,   bsdoput,	bsdopen,   bsdclose,   "bsd", 0, 1 };
 
 Qinfo *protocols[] = { &tcpinfo, &udpinfo, &ilinfo, 0 };
 
@@ -274,6 +280,18 @@ ipwrite(Chan *c, char *a, long n, ulong offset)
 		else if(cp->stproto == &ilinfo)
 			ilstart(cp, IL_ACTIVE, 20);
 
+		/*
+		 *  stupid hack for BSD port's 512, 513, & 514
+		 *  to make it harder for user to lie about his
+		 *  identity. -- presotto
+		 */
+		switch(cp->pdst){
+		case 512:
+		case 513:
+		case 514:
+			pushq(c->stream, &bsdinfo);
+			break;
+		}
 	}
 	else if(strcmp(field[0], "disconnect") == 0) {
 		if(cp->stproto != &udpinfo)
@@ -986,3 +1004,85 @@ ip_conn(Ipconv *ic, Port dst, Port src, Ipaddr dest, char proto)
 
 	return 0;
 }
+
+/*
+ *  Fuck me sideways with a bargepole!!! -- philw
+ *
+ *  BSD authentication protocol, used on ports 512, 513, & 514.
+ *  This makes sure that a user can only write the REAL user id.
+ *
+ *  q->ptr is number of nulls seen
+ */
+void
+bsdopen(Queue *q, Stream *s)
+{
+	RD(q)->ptr = q;
+	WR(q)->ptr = q;
+}
+void
+bsdclose(Queue *q)
+{
+	Block *bp;
+
+	bp = allocb(0);
+	bp->type = M_HANGUP;
+	PUTNEXT(q->other, bp);
+}
+void
+bsdiput(Queue *q, Block *bp)
+{
+	PUTNEXT(q, bp);
+}
+void
+bsdoput(Queue *q, Block *bp)
+{
+	uchar *luser;
+	uchar *p;
+	Block *nbp;
+	int n;
+
+	/* just pass it on if we've done authentication */
+	if(q->ptr == 0 || bp->type != M_DATA){
+		PUTNEXT(q, bp);
+		return;
+	}
+
+	/* collect into a single block */
+	lock(q);
+	if(q->first == 0)
+		q->first = pullup(bp, blen(bp));
+	else{
+		nbp = q->first;
+		nbp->next = bp;
+		q->first = pullup(nbp, blen(nbp));
+	}
+	bp = q->first;
+	if(bp == 0){
+		unlock(q);
+		bsdclose(q);
+		return;
+	}
+
+	/* look for 2 nulls to indicate stderr port and local user */
+	luser = memchr(bp->rptr, 0, BLEN(bp));
+	if(luser == 0){
+		unlock(q);
+		return;
+	}
+	luser++;
+	if(memchr(luser, 0, bp->wptr - luser) == 0){
+		unlock(q);
+		return;
+	}
+
+	/* if luser is a lie, hangup */
+	if(memcmp(luser, u->p->user, strlen(u->p->user)+1) != 0)
+		bsdclose(q);
+
+	/* mark queue as authenticated and pass data to remote side */
+	q->ptr = 0;
+	q->first = 0;
+	bp->flags |= S_DELIM;
+	PUTNEXT(q, bp);
+	unlock(q);
+}
diff --git a/port/stream.c b/port/stream.c
index a82f6ea9b96e537887e26779c4a54a92e2641c46..ca3b97fb4bf9e30d8f4ba14ed8514730c4091e91 100644
--- a/port/stream.c
+++ b/port/stream.c
@@ -604,7 +604,7 @@ pullup(Block *bp, int n)
 	n -= BLEN(bp);
 	while(nbp = bp->next){
 		i = BLEN(nbp);
-		if(i > n) {
+		if(i >= n) {
 			memmove(bp->wptr, nbp->rptr, n);
 			bp->wptr += n;
 			nbp->rptr += n;
@@ -622,7 +622,7 @@ pullup(Block *bp, int n)
 }
 
 /*
- *  expand a block list to be one byte, len bytes long
+ *  expand a block list to be one block, len bytes long
  */
 Block*
 expandb(Block *bp, int len)
diff --git a/port/tcpif.c b/port/tcpif.c
index ca3856aee6d8b6ec6a5cc56f8e6d6fdd777e08b5..6ced887ae15beb3be1e49fccaa56c3202c1fe08b 100644
--- a/port/tcpif.c
+++ b/port/tcpif.c
@@ -72,6 +72,7 @@ void
 tcpstart(Ipconv *s, int mode, ushort window, char tos)
 {
 	Tcpctl *tcb = &s->tcpctl;
+	char msg[NAMELEN+2];
 
 	if(tcb->state != Closed)
 		return;