From 6ed5f87bccc9666b0d9984229c71a2c7559a7103 Mon Sep 17 00:00:00 2001
From: David du Colombier <0intro@gmail.com>
Date: Tue, 28 Jan 1992 00:00:00 +0000
Subject: [PATCH] Plan 9 from Bell Labs 1992-01-28

---
 port/devip.c    | 35 +++++++++++++++++++++++++++--------
 port/devproc.c  |  5 +++++
 port/ipdat.h    | 10 +++++++---
 port/pgrp.c     | 16 +++++-----------
 port/portdat.h  | 12 ++++++++++++
 port/tcpinput.c |  8 +++++++-
 port/tcptimer.c |  2 +-
 7 files changed, 64 insertions(+), 24 deletions(-)

diff --git a/port/devip.c b/port/devip.c
index aaf9ea270654a5689f8de82273f23d240f29860d..b20872dbdb1d1007b5bef6110dd23d29645b1b2c 100644
--- a/port/devip.c
+++ b/port/devip.c
@@ -212,9 +212,9 @@ ipread(Chan *c, void *a, long n, ulong offset)
 long
 ipwrite(Chan *c, char *a, long n, ulong offset)
 {
-	int 	m, backlog, type;
+	int 	m, backlog, type, priv;
 	char 	*field[5], *ctlarg[5], buf[256];
-	Port	port, base;
+	Port	port;
 	Ipconv  *cp;
 
 	type = STREAMTYPE(c->qid.path);
@@ -248,12 +248,12 @@ ipwrite(Chan *c, char *a, long n, ulong offset)
 		default:
 			error(Ebadarg);
 		case 2:
-			base = PORTALLOC;
+			priv = 0;
 			break;
 		case 3:
 			if(strcmp(ctlarg[2], "r") != 0)
 				error(Eperm);
-			base = PRIVPORTALLOC;
+			priv = 1;
 			break;
 		}
 		cp->dst = ipparse(ctlarg[0]);
@@ -262,7 +262,7 @@ ipwrite(Chan *c, char *a, long n, ulong offset)
 		/* If we have no local port assign one */
 		qlock(&ipalloc);
 		if(cp->psrc == 0)
-			cp->psrc = nextport(ipconv[c->dev], base);
+			cp->psrc = nextport(ipconv[c->dev], priv);
 		qunlock(&ipalloc);
 
 		if(cp->stproto == &tcpinfo)
@@ -557,6 +557,7 @@ tcpstopen(Queue *q, Stream *s)
 
 	ipc->readq = RD(q);
 	ipc->readq->rp = &tcpflowr;
+	ipc->err = 0;
 
 	RD(q)->ptr = (void *)ipc;
 	WR(q)->next->ptr = (void *)ipc->ipinterface;
@@ -852,14 +853,32 @@ portused(Ipconv *ic, Port port)
 	return 0;
 }
 
+static Port lastport[2] = { PORTALLOC-1, PRIVPORTALLOC-1 };
+
 Port
-nextport(Ipconv *ic, Port base)
+nextport(Ipconv *ic, int priv)
 {
+	Port base;
+	Port max;
+	Port *p;
 	Port i;
 
-	for(i = base; i < PORTMAX; i++)
+	if(priv){
+		base = PRIVPORTALLOC;
+		max = PORTALLOC;
+		p = &lastport[1];
+	} else {
+		base = PORTALLOC;
+		max = PORTMAX;
+		p = &lastport[0];
+	}
+	
+	for(i = *p + 1; i < max; i++)
+		if(!portused(ic, i))
+			return(*p = i);
+	for(i = base ; i <= *p; i++)
 		if(!portused(ic, i))
-			return(i);
+			return(*p = i);
 
 	return(0);
 }
diff --git a/port/devproc.c b/port/devproc.c
index 1b73c44dee954c58ca503aa25059379556a5d28d..b0ff664e486e235869ef5bf67a96891e5336ebfb 100644
--- a/port/devproc.c
+++ b/port/devproc.c
@@ -264,6 +264,11 @@ procread(Chan *c, void *va, long n, ulong offset)
 		}
 
 		if(offset >= KZERO) {
+			/* prevent users reading authentication crypt keys */
+			if(offset >= pgrpalloc.cryptbase)
+			if(offset < pgrpalloc.crypttop)
+				error(Eperm);
+			/* validate physical kernel addresses */
 			if(offset < KZERO+conf.npage0*BY2PG){
 				if(offset+n > KZERO+conf.npage0*BY2PG)
 					n = KZERO+conf.npage0*BY2PG - offset;
diff --git a/port/ipdat.h b/port/ipdat.h
index d7101c6a5e1cac587725ca43e7bf1db88578821d..f110b2b1c0300d5bccbacc7d41e7c6a1ae90ba6e 100644
--- a/port/ipdat.h
+++ b/port/ipdat.h
@@ -194,9 +194,8 @@ struct Timer
 	void	*arg;
 };
 
-struct Tcpctl
+struct Tctl
 {
-	QLock;
 	uchar	state;		/* Connection state */
 	uchar	type;		/* Listening or active connection */
 	uchar	code;		/* Icmp code */		
@@ -242,6 +241,11 @@ struct Tcpctl
 	int	srtt;			/* Shortened round trip */
 	int	mdev;			/* Mean deviation of round trip */
 };
+struct Tcpctl
+{
+	QLock;
+	struct Tctl;
+};
 
 struct	Tcp
 {
@@ -435,7 +439,7 @@ void	udprcvmsg(Ipconv *, Block*);
 Block	*btrim(Block*, int, int);
 Block	*ip_reassemble(int, Block*, Etherhdr*);
 Ipconv	*portused(Ipconv *, Port);
-Port	nextport(Ipconv *, Port);
+Port	nextport(Ipconv *, int);
 Fragq   *ipfragallo(void);
 void	ipfragfree(Fragq*, int);
 void	iproute(uchar*, uchar*);
diff --git a/port/pgrp.c b/port/pgrp.c
index 9848a5f3ea7aaaab69215a31c94ee8dc41500cbc..15595912367d100e4a3e0d2ed549d0b074ae1b56 100644
--- a/port/pgrp.c
+++ b/port/pgrp.c
@@ -5,13 +5,7 @@
 #include	"fns.h"
 #include	"../port/error.h"
 
-struct
-{
-	Lock;
-	Pgrp	*arena;
-	Pgrp	*free;
-	ulong	pgrpid;
-}pgrpalloc;
+Pgrps pgrpalloc;
 
 struct
 {
@@ -43,10 +37,10 @@ grpinit(void)
 	Mhead *hm, *hem;
 	Crypt *cr;
 
-	/*
-	 * need to /dev/proc read protect crypt memory
-	 */
-	cr = ialloc(conf.npgrp*sizeof(Crypt), 0);
+	i = conf.npgrp*sizeof(Crypt);
+	cr = ialloc(i, 0);
+	pgrpalloc.cryptbase = (ulong)cr;
+	pgrpalloc.crypttop = (ulong)cr + i;
 	pgrpalloc.arena = ialloc(conf.npgrp*sizeof(Pgrp), 0);
 	pgrpalloc.free = pgrpalloc.arena;
 
diff --git a/port/portdat.h b/port/portdat.h
index f3fd35cb28ba5c3d9c310b7e390efc8207b3a045..95cd8e554394285482837c2b819286b0a5acdb80 100644
--- a/port/portdat.h
+++ b/port/portdat.h
@@ -23,6 +23,7 @@ typedef struct Network	Network;
 typedef struct Note	Note;
 typedef struct Page	Page;
 typedef struct Palloc	Palloc;
+typedef struct Pgrps	Pgrps;
 typedef struct Pgrp	Pgrp;
 typedef struct Proc	Proc;
 typedef struct Pte	Pte;
@@ -427,6 +428,16 @@ struct Palloc
 	int	wanted;			/* Do the wakeup at free */
 };
 
+struct Pgrps
+{
+	Lock;
+	Pgrp	*arena;
+	Pgrp	*free;
+	ulong	pgrpid;
+	ulong	cryptbase;
+	ulong	crypttop;
+};
+
 struct Waitq
 {
 	Waitmsg	w;
@@ -672,6 +683,7 @@ extern	char	devchar[];
 extern	char	*conffile;
 extern	char	*statename[];
 extern	Palloc 	palloc;
+extern	Pgrps 	pgrpalloc;
 extern  Image	swapimage;
 extern  char	eve[];
 extern	int	nrdy;
diff --git a/port/tcpinput.c b/port/tcpinput.c
index 0e70c891b3da76682066ba3205aa8e6eaf4e1460..6eeef0e998ac0d7f7bfc053a91314c15a985476d 100644
--- a/port/tcpinput.c
+++ b/port/tcpinput.c
@@ -824,13 +824,19 @@ copyb(Block *bp, int count)
 ushort tcp_mss = DEF_MSS;	/* Maximum segment size to be sent with SYN */
 int tcp_irtt = DEF_RTT;		/* Initial guess at round trip time */
 
+static void
+cleartcp(struct Tctl *a)
+{
+	memset(a, 0, sizeof(struct Tctl));
+}
+
 void
 init_tcpctl(Ipconv *s)
 {
 
 	Tcpctl *tcb = &s->tcpctl;
 
-	memset(tcb, 0, sizeof(Tcpctl));
+	cleartcp(tcb);
 
 	tcb->cwind = tcb->mss = tcp_mss;
 	tcb->ssthresh = 65535;
diff --git a/port/tcptimer.c b/port/tcptimer.c
index debc17ef3a36320d0d42519e5071ebeffb47e8c1..50c2052f9661d607b2d358ce8e1ac52345650f8c 100644
--- a/port/tcptimer.c
+++ b/port/tcptimer.c
@@ -1,4 +1,4 @@
-
#include	"u.h"
+#include	"u.h"
 #include	"lib.h"
 #include	"mem.h"
 #include	"dat.h"