From 9119b0c8af15333796e02433677a54e952b1a73d Mon Sep 17 00:00:00 2001 From: Michael Brown Date: Tue, 19 May 2009 15:54:35 +0100 Subject: [PATCH] [dhcp] Perform ProxyDHCP only if we do not already have PXE options This prevents gPXE from wasting time attempting to contact a ProxyDHCP server on port 4011 if the DHCP response already contains the relevant PXE options. This behaviour is hinted at (though not explicitly specified) in the PXE spec, and seems to match what the Intel client does. Suggested-by: Simon Kelley --- src/net/udp/dhcp.c | 8 ++++++-- 1 file changed, 6 insertions(+), 2 deletions(-) diff --git a/src/net/udp/dhcp.c b/src/net/udp/dhcp.c index 9c1e09da..851b75e1 100644 --- a/src/net/udp/dhcp.c +++ b/src/net/udp/dhcp.c @@ -335,6 +335,8 @@ static void dhcp_discovery_rx ( struct dhcp_session *dhcp, char vci[9]; /* "PXEClient" */ int vci_len; int has_pxeclient; + int pxeopts_len; + int has_pxeopts; int8_t priority = 0; uint8_t no_pxedhcp = 0; unsigned long elapsed; @@ -355,8 +357,10 @@ static void dhcp_discovery_rx ( struct dhcp_session *dhcp, vci, sizeof ( vci ) ); has_pxeclient = ( ( vci_len >= ( int ) sizeof ( vci ) ) && ( strncmp ( "PXEClient", vci, sizeof (vci) ) == 0 )); + pxeopts_len = dhcppkt_fetch ( dhcppkt, DHCP_VENDOR_ENCAP, NULL, 0 ); + has_pxeopts = ( pxeopts_len >= 0 ); if ( has_pxeclient ) - DBGC ( dhcp, " pxe" ); + DBGC ( dhcp, "%s", ( has_pxeopts ? " pxe" : " proxy" ) ); /* Identify priority */ dhcppkt_fetch ( dhcppkt, DHCP_EB_PRIORITY, &priority, @@ -382,7 +386,7 @@ static void dhcp_discovery_rx ( struct dhcp_session *dhcp, } /* Select as ProxyDHCP offer, if applicable */ - if ( has_pxeclient && ( msgtype == DHCPOFFER ) && + if ( has_pxeclient && ( ! has_pxeopts ) && ( msgtype == DHCPOFFER ) && ( priority >= dhcp->proxy_priority ) ) { dhcp->proxy_server = server_id; dhcp->proxy_priority = priority;