[U-Boot] [PATCH 2/2] efi_loader: set the dhcp ack received flag

[Patrick Wildt <patrick@blueri.se>]

On Wed, Apr 10, 2019 at 11:20:35AM +0200, Patrick Wildt wrote:
> On Thu, Jan 31, 2019 at 07:29:04PM +0100, Heinrich Schuchardt wrote:
> > Do we really need multiple functions to update the DHCP status?
> > 
> > I would prefer a single function with a parameter telling which DHCP
> > status has been reached.
> > 
> 
> I think this diff below might be better.  There we have an update
> function that is called after it switch the state, and on REQUESTING
> we save the packet information and on BOUND we received the ack.
> 
> > 
> > The current network device can be determined via eth_get_dev().
> > In function eth_current_changed() this eth_get_dev() function is used to
> > update the ethact environment variable.
> > 
> > If we have a single update function we can determine the active network
> > device there.
> 
> The efi network object is only created on bootefi, so there is no DHCP
> going on at that point.  It all happens some time before bootefi is
> called.  The only thing that we could do is try to memorize for which
> ethernet we received the DHCP packets, and when we create the EFI
> network object we can try to see if the DHCP packets match to the
> current ethernet we create the object for.
> 
> Patrick

Updated diff.  We should probably reset the DHCP Ack flag when we
switch to the REQUEST state.  Thus on a second dhcp call, where we
might get a different IP (on a different device) the ACK is properly
reset.

diff --git a/include/efi_loader.h b/include/efi_loader.h
index 00b81c6010..7e8f3b04b5 100644
--- a/include/efi_loader.h
+++ b/include/efi_loader.h
@@ -290,8 +290,8 @@ efi_status_t efi_smbios_register(void);
 struct efi_simple_file_system_protocol *
 efi_fs_from_path(struct efi_device_path *fp);
 
-/* Called by networking code to memorize the dhcp ack package */
-void efi_net_set_dhcp_ack(void *pkt, int len);
+/* Called by networking code to memorize dhcp information */
+void efi_net_update_dhcp(int state, void *pkt, int len);
 /* Called by efi_set_watchdog_timer to reset the timer */
 efi_status_t efi_set_watchdog(unsigned long timeout);
 
@@ -578,7 +578,7 @@ static inline efi_status_t efi_add_runtime_mmio(void *mmio_ptr, u64 len)
 static inline void efi_restore_gd(void) { }
 static inline void efi_set_bootdev(const char *dev, const char *devnr,
 				   const char *path) { }
-static inline void efi_net_set_dhcp_ack(void *pkt, int len) { }
+static inline void efi_net_update_dhcp(int state, void *pkt, int len) {}
 static inline void efi_print_image_infos(void *pc) { }
 
 #endif /* CONFIG_IS_ENABLED(EFI_LOADER) */
diff --git a/lib/efi_loader/efi_net.c b/lib/efi_loader/efi_net.c
index c7d9da8521..192e7f0bb7 100644
--- a/lib/efi_loader/efi_net.c
+++ b/lib/efi_loader/efi_net.c
@@ -8,6 +8,7 @@
 #include <common.h>
 #include <efi_loader.h>
 #include <malloc.h>
+#include "../net/bootp.h"
 
 static const efi_guid_t efi_net_guid = EFI_SIMPLE_NETWORK_GUID;
 static const efi_guid_t efi_pxe_guid = EFI_PXE_GUID;
@@ -15,6 +16,7 @@ static struct efi_pxe_packet *dhcp_ack;
 static bool new_rx_packet;
 static void *new_tx_packet;
 static void *transmit_buffer;
+static int dhcp_ack_received;
 
 /*
  * The notification function of this event is called in every timer cycle
@@ -522,18 +524,24 @@ out:
 }
 
 /**
- * efi_net_set_dhcp_ack() - take note of a selected DHCP IP address
+ * efi_net_update_dhcp() - take note of DHCP information
  *
  * This function is called by dhcp_handler().
  */
-void efi_net_set_dhcp_ack(void *pkt, int len)
+void efi_net_update_dhcp(int state, void *pkt, int len)
 {
 	int maxsize = sizeof(*dhcp_ack);
 
 	if (!dhcp_ack)
 		dhcp_ack = malloc(maxsize);
 
-	memcpy(dhcp_ack, pkt, min(len, maxsize));
+	if (state == REQUESTING) {
+		memcpy(dhcp_ack, pkt, min(len, maxsize));
+		dhcp_ack_received = 0;
+	}
+
+	if (state == BOUND)
+		dhcp_ack_received = 1;
 }
 
 /**
@@ -645,8 +653,10 @@ efi_status_t efi_net_register(void)
 	netobj->net_mode.if_type = ARP_ETHER;
 
 	netobj->pxe.mode = &netobj->pxe_mode;
-	if (dhcp_ack)
+	if (dhcp_ack) {
 		netobj->pxe_mode.dhcp_ack = *dhcp_ack;
+		netobj->pxe_mode.dhcp_ack_received = dhcp_ack_received;
+	}
 
 	/*
 	 * Create WaitForPacket event.
diff --git a/net/bootp.c b/net/bootp.c
index 9a2b512e4a..987fc47d06 100644
--- a/net/bootp.c
+++ b/net/bootp.c
@@ -1067,11 +1067,11 @@ static void dhcp_handler(uchar *pkt, unsigned dest, struct in_addr sip,
 			    strlen(CONFIG_SYS_BOOTFILE_PREFIX)) == 0) {
 #endif	/* CONFIG_SYS_BOOTFILE_PREFIX */
 			dhcp_packet_process_options(bp);
-			efi_net_set_dhcp_ack(pkt, len);
 
 			debug("TRANSITIONING TO REQUESTING STATE\n");
 			dhcp_state = REQUESTING;
 
+			efi_net_update_dhcp(dhcp_state, pkt, len);
 			net_set_timeout_handler(5000, bootp_timeout_handler);
 			dhcp_send_request_packet(bp);
 #ifdef CONFIG_SYS_BOOTFILE_PREFIX
@@ -1090,6 +1090,7 @@ static void dhcp_handler(uchar *pkt, unsigned dest, struct in_addr sip,
 			dhcp_state = BOUND;
 			printf("DHCP client bound to address %pI4 (%lu ms)\n",
 			       &net_ip, get_timer(bootp_start));
+			efi_net_update_dhcp(dhcp_state, pkt, len);
 			net_set_timeout_handler(0, (thand_f *)0);
 			bootstage_mark_name(BOOTSTAGE_ID_BOOTP_STOP,
 					    "bootp_stop");