From: Lyle Franklin lylejfranklin@gmail.com
- ProxyDHCP allows a second DHCP server to exist alongside your main DHCP server and supply additional BOOTP related options - When u-boot sends out a DHCP request, the real DHCP server will respond with a normal response containing the new client IP address while simultaneously the ProxyDHCP server will respond with a blank client IP address and a `bootfile` option - This patch adds CONFIG_SERVERIP_FROM_PROXYDHCP (default false) to enable this behavior and CONFIG_SERVERIP_FROM_PROXYDHCP_DELAY_MS (default 100) which tells u-boot to wait additional time after receiving the main DHCP response to give the ProxyDHCP response time to arrive - The PXE spec for ProxyDHCP is more complicated than the solution added here as diagramed on page 16: http://www.pix.net/software/pxeboot/archive/pxespec.pdf:
``` DHCP Discover will be retried four times. The four timeouts are 4, 8, 16 and 32 seconds respectively. If a DHCPOFFER is received without an Option timeouts in an attempt to receive a PXE response. ```
- Adding a simple delay worked for my purposes but let me know if a more robust solution is required
Signed-off-by: Lyle Franklin lylejfranklin@gmail.com ---
net/Kconfig | 14 ++++++++++++++ net/bootp.c | 27 ++++++++++++++++++++++----- 2 files changed, 36 insertions(+), 5 deletions(-)
diff --git a/net/Kconfig b/net/Kconfig index 68cecf75a2..e46eb7833a 100644 --- a/net/Kconfig +++ b/net/Kconfig @@ -35,4 +35,18 @@ config TFTP_BLOCKSIZE help Default TFTP block size.
+config SERVERIP_FROM_PROXYDHCP + bool "Get serverip value from Proxy DHCP response" + help + Allows bootfile config to be fetched from Proxy DHCP server + while IP is obtained from main DHCP server. + +config SERVERIP_FROM_PROXYDHCP_DELAY_MS + int "# of additional milliseconds to wait for ProxyDHCP response" + default 100 + help + Amount of additional time to wait for ProxyDHCP response after + receiving response from main DHCP server. Has no effect if + SERVERIP_FROM_PROXYDHCP is false. + endif # if NET diff --git a/net/bootp.c b/net/bootp.c index 9a2b512e4a..218dfde728 100644 --- a/net/bootp.c +++ b/net/bootp.c @@ -140,10 +140,7 @@ static int check_reply_packet(uchar *pkt, unsigned dest, unsigned src, return retval; }
-/* - * Copy parameters of interest from BOOTP_REPLY/DHCP_OFFER packet - */ -static void store_net_params(struct bootp_hdr *bp) +static void store_bootp_params(struct bootp_hdr *bp) { #if !defined(CONFIG_BOOTP_SERVERIP) struct in_addr tmp_ip; @@ -176,6 +173,16 @@ static void store_net_params(struct bootp_hdr *bp) */ if (*net_boot_file_name) env_set("bootfile", net_boot_file_name); +#endif +} + +/* + * Copy parameters of interest from BOOTP_REPLY/DHCP_OFFER packet + */ +static void store_net_params(struct bootp_hdr *bp) +{ +#if !defined(CONFIG_SERVERIP_FROM_PROXYDHCP) + store_bootp_params(bp); #endif net_copy_ip(&net_ip, &bp->bp_yiaddr); } @@ -1049,8 +1056,12 @@ 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) + if (net_read_ip(&bp->bp_yiaddr).s_addr == 0) { +#if defined(CONFIG_SERVERIP_FROM_PROXYDHCP) + store_bootp_params(bp); +#endif return; + }
switch (dhcp_state) { case SELECTING: @@ -1069,6 +1080,12 @@ static void dhcp_handler(uchar *pkt, unsigned dest, struct in_addr sip, dhcp_packet_process_options(bp); efi_net_set_dhcp_ack(pkt, len);
+#if defined(CONFIG_SERVERIP_FROM_PROXYDHCP) + if (!net_server_ip.s_addr) + udelay(CONFIG_SERVERIP_FROM_PROXYDHCP_DELAY_MS * + 1000); +#endif /* CONFIG_SERVERIP_FROM_PROXYDHCP */ + debug("TRANSITIONING TO REQUESTING STATE\n"); dhcp_state = REQUESTING;