buffer not large enough for SHA1 hash

Reference: /n/sources/patch/applied/tls-buffer
Date: Wed Jan  9 00:14:11 CET 2013
Signed-off-by: quanstro@quanstro.net

--- /sys/src/9/port/devtls.c	Wed Jan  9 00:14:05 2013
+++ /sys/src/9/port/devtls.c	Wed Jan  9 00:14:01 2013
@@ -732,7 +732,7 @@
 {
 	OneWay *volatile in;
 	Block *volatile b;
-	uchar *p, seq[8], header[RecHdrLen], hmac[MD5dlen];
+	uchar *p, seq[8], header[RecHdrLen], hmac[MaxMacLen];
 	int volatile nconsumed;
 	int len, type, ver, unpad_len;
 
@@ -1323,7 +1323,7 @@
 
 	tr = tlsdevs[CONV(c->qid)];
 	if(tr == nil)
-		panic("tlsbread");
+		panic("tlsbwrite");
 
 	ty = TYPE(c->qid);
 	switch(ty) {