Re: broadcast packets not reaching sender on if_hwassist capable interfaces
Summary: FreeBSD 4.3 Broadcast IP datagrams not looping on Broadcom GigE card. > Also, why is the decision to loop the packet back made in ether_output > rather than in ip_output? Off the top of my head I can't see any > particular advantage, but perhaps there is. The disadvantage is that I > will have to disable hardware assist for broadcast packets to make things > work right. the bge sets the interface output to be ether_output() which is called from the ip_output() after all thse flags have been set.. Are these packets that fail part of a IP fragment? m_copy does not copy the hwassist flags. we see the same problem with multicast packets. Bill Fenner wrote a simular multicast patch before FreeBSD 4.5-RELEASE, but even that fix has not been included into the tree yet either. In ip_output, we should either we need to copy the hwassist flag in _copy or in the code that follows a m_copy, or force the checksum calculations. if your packets are not part of a fragment, then let me know. --mark tinguely. To Unsubscribe: send mail to [EMAIL PROTECTED] with "unsubscribe freebsd-hackers" in the body of the message
broadcast packets not reaching sender on if_hwassist capable interfaces
Hi, I was chasing an interesting problem in our FreeBSD 4.3 codebase today. Broadcast IP datagrams were not being received by programs on the same system the IP datagrams were sent from. They were making it out the wire. The were being sent on a Broadcom GigE interface that has hardware checksumming. After a while we realized that what was happening was that the packets were being marked for hardware checksumming in ip_output (m->m_pkthdr.csum_flags), but the decision about looping a packet back to ourselves is made in ether_output, so the packet is never checksummed and is discarded in ip_input. Has this been fixed in a subsequent release? Also, why is the decision to loop the packet back made in ether_output rather than in ip_output? Off the top of my head I can't see any particular advantage, but perhaps there is. The disadvantage is that I will have to disable hardware assist for broadcast packets to make things work right. Regards - Richard Sharpe, [EMAIL PROTECTED], [EMAIL PROTECTED], [EMAIL PROTECTED] To Unsubscribe: send mail to [EMAIL PROTECTED] with "unsubscribe freebsd-hackers" in the body of the message
