first draft

2022-04-13 18:01:39 +08:00
commit 906782e134
111 changed files with 15383 additions and 0 deletions
--- a/cksum.c
+++ b/cksum.c
@ -0,0 +1,41 @@
+/* 
+ * $smu-mark$ 
+ * $name: cksum.c$ 
+ * $author: Salvatore Sanfilippo <antirez@invece.org>$ 
+ * $copyright: Copyright (C) 1999 by Salvatore Sanfilippo$ 
+ * $license: This software is under GPL version 2 of license$ 
+ * $date: Fri Nov  5 11:55:47 MET 1999$ 
+ * $rev: 8$ 
+ */ 
+
+#include "hping2.h"	/* only for arch semi-indipendent data types */
+#include "globals.h"
+
+/*
+ * from R. Stevens's Network Programming
+ */
+__u16 cksum(__u16 *buf, int nbytes)
+{
+	__u32 sum;
+	__u16 oddbyte;
+
+	sum = 0;
+	while (nbytes > 1) {
+		sum += *buf++;
+		nbytes -= 2;
+	}
+
+	if (nbytes == 1) {
+		oddbyte = 0;
+		*((__u16 *) &oddbyte) = *(__u16 *) buf;
+		sum += oddbyte;
+	}
+
+	sum = (sum >> 16) + (sum & 0xffff);
+	sum += (sum >> 16);
+
+	/* return a bad checksum with --badcksum option */
+	if (opt_badcksum) sum ^= 0x5555;
+
+	return (__u16) ~sum;
+}