> The checksum of the whole packet minus the ethernet > header is quite useful. > > It is easy to use this to verify the TCP checksum: > calculate the > checksum of most parts of the IP header (not the > source or destination > addres) in software (fast), subtract that from the > hardware-calculated > whole packet checksum, and add other fields of the > TCP pseudo header. In fact, as pseudo header used in checksum computation has similar fields with the ip header, a substraction seems fine. But by having a look at the tcp_v4_recv() function, and more precisely inside tcp_v4_checksum_init() code, skb->csum is used 'as is' when skb->ip_summed is set to CHECKSUM_HW. There is no substraction at all. That's the problem :/ ___________________________________________________________ Do You Yahoo!? -- Une adresse @yahoo.fr gratuite et en français ! Yahoo! Mail : http://fr.mail.yahoo.com - : send the line "unsubscribe linux-net" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
