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

[Patrick Wildt]

On Mon, Mar 26, 2018 at 06:39:06AM +0200, Heinrich Schuchardt wrote:
> On 03/25/2018 10:23 PM, Patrick Wildt wrote:
> > On Sun, Mar 25, 2018 at 10:04:55PM +0200, Heinrich Schuchardt wrote:
> >> Thank you for the explanation. I think the right way go ahead is to add
> >> all missing fields and to do away with unused[].
> >>
> >> Please, carefully observe the alignment. The spec defines BOOLEAN as
> >> 8bit value. ToS is the 19th byte followed by an EFI_IP_ADDRESS which is
> >> a 16-byte buffer aligned on a 4-byte boundary. So after ToS we need one
> >> byte to ensure alignment. We could define a struct efi_ip_address as
> >> u8 a[16] __attribute__((aligned(4))).
> >>
> >> Best regards
> >>
> >> Heinrich
> > 
> > I have noticed that, yes.  I think explicitly padding the struct gives
> > better visibility of the issue, instead of relying on an implicit
> > alignment.  Two other structures in u-boot EFI headers contain explicit
> > "pad" members.  I'd feel safer to go that route.  What do you think
> > about the following?
> > 
> > Best regards,
> > Patrick
> 
> I think it is fine to use a padding byte. But still the alignment should
> be specified for efi_ip_address. Otherwise we might pass data with wrong
> alignment.
> 
> Best regards
> 
> Heinrich

EDK2 does this by defining EFI_IP_ADDRESS to a union which includes a
uint32_t addr[4], but I guess the attribute makes it more explicit.
This should do:

Best regards,
Patrick

diff --git a/include/efi_api.h b/include/efi_api.h
index 3ba650e57e..06789acdd1 100644
--- a/include/efi_api.h
+++ b/include/efi_api.h
@@ -662,7 +662,7 @@ struct efi_mac_address {
 
 struct efi_ip_address {
 	u8 ip_addr[16];
-};
+} __attribute__((aligned(4)));
 
 enum efi_simple_network_state {
 	EFI_NETWORK_STOPPED,
@@ -756,7 +756,28 @@ struct efi_pxe_packet {
 
 struct efi_pxe_mode
 {
-	u8 unused[52];
+	u8 started;
+	u8 ipv6_available;
+	u8 ipv6_supported;
+	u8 using_ipv6;
+	u8 bis_supported;
+	u8 bis_detected;
+	u8 auto_arp;
+	u8 send_guid;
+	u8 dhcp_discover_valid;
+	u8 dhcp_ack_received;
+	u8 proxy_offer_received;
+	u8 pxe_discovervalid;
+	u8 pxe_reply_received;
+	u8 pxe_bis_reply_received;
+	u8 icmp_error_received;
+	u8 tftp_error_received;
+	u8 make_callbacks;
+	u8 ttl;
+	u8 tos;
+	u8 pad;
+	struct efi_ip_address station_ip;
+	struct efi_ip_address subnet_mask;
 	struct efi_pxe_packet dhcp_discover;
 	struct efi_pxe_packet dhcp_ack;
 	struct efi_pxe_packet proxy_offer;