[U-Boot] [PATCH V2] net: bootp: Ignore packets whose yiaddr is 0
From: Peng Fan peng.fan@nxp.com
When doing `dhcp`, there is a bad dhcp server in my network which always reply dhcp request with yiaddr 0, which cause uboot can not successfully get ipaddr from the good dhcp server. But the Linux PC can get the ip address even if there is a bad dhcp server. This patch is to fix that even if there is a bad dhcp server, uboot can still get ipaddr and tftp work ok.
The way is to ignore the packets from the bad dhcp server by filtering out the yiaddr whose value is 0.
Signed-off-by: Peng Fan peng.fan@nxp.com Cc: Joe Hershberger joe.hershberger@ni.com ---
Changes V2: Take Wolfgang's suggestion, move the code after debug message.
net/bootp.c | 3 +++ 1 file changed, 3 insertions(+)
diff --git a/net/bootp.c b/net/bootp.c index 8aeddb0..8da2e9b 100644 --- a/net/bootp.c +++ b/net/bootp.c @@ -995,6 +995,9 @@ static void dhcp_handler(uchar *pkt, unsigned dest, struct in_addr sip, debug("DHCPHandler: got DHCP packet: (src=%d, dst=%d, len=%d) state: " "%d\n", src, dest, len, dhcp_state);
+ if (net_read_ip(&bp->bp_yiaddr).s_addr == 0) + return; + switch (dhcp_state) { case SELECTING: /*
Dear Peng Fan,
In message 1452151703-30647-1-git-send-email-van.freenix@gmail.com you wrote:
From: Peng Fan peng.fan@nxp.com
When doing `dhcp`, there is a bad dhcp server in my network which always reply dhcp request with yiaddr 0, which cause uboot can not successfully get ipaddr from the good dhcp server. But the Linux PC can get the ip address even if there is a bad dhcp server. This patch is to fix that even if there is a bad dhcp server, uboot can still get ipaddr and tftp work ok.
The way is to ignore the packets from the bad dhcp server by filtering out the yiaddr whose value is 0.
Signed-off-by: Peng Fan peng.fan@nxp.com Cc: Joe Hershberger joe.hershberger@ni.com
Changes V2: Take Wolfgang's suggestion, move the code after debug message.
THanks.
Reviewed-by: Wolfgang Denk wd@denx.de
Best regards,
Wolfgang Denk
Gentle ping..
Regards, Peng.
On Thu, Jan 07, 2016 at 05:09:04PM +0100, Wolfgang Denk wrote:
Dear Peng Fan,
In message 1452151703-30647-1-git-send-email-van.freenix@gmail.com you wrote:
From: Peng Fan peng.fan@nxp.com
When doing `dhcp`, there is a bad dhcp server in my network which always reply dhcp request with yiaddr 0, which cause uboot can not successfully get ipaddr from the good dhcp server. But the Linux PC can get the ip address even if there is a bad dhcp server. This patch is to fix that even if there is a bad dhcp server, uboot can still get ipaddr and tftp work ok.
The way is to ignore the packets from the bad dhcp server by filtering out the yiaddr whose value is 0.
Signed-off-by: Peng Fan peng.fan@nxp.com Cc: Joe Hershberger joe.hershberger@ni.com
Changes V2: Take Wolfgang's suggestion, move the code after debug message.
THanks.
Reviewed-by: Wolfgang Denk wd@denx.de
Best regards,
Wolfgang Denk
-- DENX Software Engineering GmbH, Managing Director: Wolfgang Denk HRB 165235 Munich, Office: Kirchenstr.5, D-82194 Groebenzell, Germany Phone: (+49)-8142-66989-10 Fax: (+49)-8142-66989-80 Email: wd@denx.de About the use of language: it is impossible to sharpen a pencil with a blunt ax. It is equally vain to try to do it with ten blunt axes instead. -- Edsger Dijkstra
On Thu, Jan 7, 2016 at 1:28 AM, Peng Fan van.freenix@gmail.com wrote:
From: Peng Fan peng.fan@nxp.com
When doing `dhcp`, there is a bad dhcp server in my network which always reply dhcp request with yiaddr 0, which cause uboot can not successfully get ipaddr from the good dhcp server. But the Linux PC can get the ip address even if there is a bad dhcp server. This patch is to fix that even if there is a bad dhcp server, uboot can still get ipaddr and tftp work ok.
The way is to ignore the packets from the bad dhcp server by filtering out the yiaddr whose value is 0.
Signed-off-by: Peng Fan peng.fan@nxp.com Cc: Joe Hershberger joe.hershberger@ni.com
Acked-by: Joe Hershberger joe.hershberger@ni.com
participants (4)
-
Joe Hershberger -
Joe Hershberger -
Peng Fan -
Wolfgang Denk