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Back out back checksum changes

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Ted Lemon
1997-03-05 20:06:03 +00:00
parent e7b9429fea
commit 35a50d44e9
1 changed files with 12 additions and 6 deletions
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18
common/packet.c
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@@ -40,10 +40,9 @@
* Enterprises, see ``http://www.vix.com''. * Enterprises, see ``http://www.vix.com''.
*/ */
#ifndef lint #ifndef lint
static char copyright[] = static char copyright[] =
"$Id: packet.c,v 1.13 1997/03/05 06:15:00 mellon Exp $ Copyright (c) 1996 The Internet Software Consortium. All rights reserved.\n"; "$Id: packet.c,v 1.14 1997/03/05 20:06:03 mellon Exp $ Copyright (c) 1996 The Internet Software Consortium. All rights reserved.\n";
#endif /* not lint */ #endif /* not lint */
#include "dhcpd.h" #include "dhcpd.h"
@@ -76,6 +75,7 @@ static u_int32_t checksum (buf, nbytes, sum)
#endif #endif
sum += (u_int16_t) ntohs(*((u_int16_t *)buf)++); sum += (u_int16_t) ntohs(*((u_int16_t *)buf)++);
} }
/* If there's a single byte left over, checksum it, too. Network /* If there's a single byte left over, checksum it, too. Network
byte order is big-endian, so the remaining byte is the high byte. */ byte order is big-endian, so the remaining byte is the high byte. */
if (i < nbytes) { if (i < nbytes) {
@@ -97,20 +97,26 @@ static u_int32_t wrapsum (sum)
#ifdef DEBUG_CHECKSUM #ifdef DEBUG_CHECKSUM
debug ("wrapsum (%x)", sum); debug ("wrapsum (%x)", sum);
#endif #endif
while (sum >> 16) {
while (sum > 0x10000) {
sum = (sum >> 16) + (sum & 0xFFFF);
#ifdef DEBUG_CHECKSUM_VERBOSE
debug ("sum = %x", sum);
#endif
sum += (sum >> 16);
#ifdef DEBUG_CHECKSUM_VERBOSE #ifdef DEBUG_CHECKSUM_VERBOSE
debug ("sum = %x", sum); debug ("sum = %x", sum);
#endif #endif
sum = (sum & 0xFFFF) + (sum >> 16);
} }
sum = sum ^ 0xFFFF;
#ifdef DEBUG_CHECKSUM_VERBOSE #ifdef DEBUG_CHECKSUM_VERBOSE
debug ("sum = %x", sum); debug ("sum = %x", sum);
#endif #endif
#ifdef DEBUG_CHECKSUM #ifdef DEBUG_CHECKSUM
debug ("wrapsum returns %x", htons (~sum)); debug ("wrapsum returns %x", htons (sum));
#endif #endif
return htons(~sum); return htons(sum);
} }
#endif /* PACKET_ASSEMBLY || PACKET_DECODING */ #endif /* PACKET_ASSEMBLY || PACKET_DECODING */