net: bootp: add PXE/RFC 4578 DHCP options support

These options are required to be present in RFC 4578 compliant DHCP
requests. They give more information to DHCP servers to allow serving

different DHCP responses to different systems based on client
architecture, client capabilities, UUID, or vendor.
Signed-off-by: NJason Hobbs <jason.hobbs@calxeda.com>

net/bootp.c

@@ -381,6 +381,11 @@ static int DhcpExtended (u8 * e, int message_type, IPaddr_t ServerID, IPaddr_t R
 {
 	u8 *start = e;
 	u8 *cnt;
+#if defined(CONFIG_BOOTP_PXE)
+	char *uuid;
+	size_t vci_strlen;
+	u16 clientarch;
+#endif
 
 #if defined(CONFIG_BOOTP_VENDOREX)
 	u8 *x;
@@ -435,6 +440,41 @@ static int DhcpExtended (u8 * e, int message_type, IPaddr_t ServerID, IPaddr_t R
 	}
 #endif
 
+#if defined(CONFIG_BOOTP_PXE)
+	clientarch = CONFIG_BOOTP_PXE_CLIENTARCH;
+	*e++ = 93;	/* Client System Architecture */
+	*e++ = 2;
+	*e++ = (clientarch >> 8) & 0xff;
+	*e++ = clientarch & 0xff;
+
+	*e++ = 94;	/* Client Network Interface Identifier */
+	*e++ = 3;
+	*e++ = 1;	/* type field for UNDI */
+	*e++ = 0;	/* major revision */
+	*e++ = 0;	/* minor revision */
+
+	uuid = getenv("pxeuuid");
+
+	if (uuid) {
+		if (uuid_str_valid(uuid)) {
+			*e++ = 97;	/* Client Machine Identifier */
+			*e++ = 17;
+			*e++ = 0;	/* type 0 - UUID */
+
+			uuid_str_to_bin(uuid, e);
+			e += 16;
+		} else {
+			printf("Invalid pxeuuid: %s\n", uuid);
+		}
+	}
+
+	*e++ = 60;	/* Vendor Class Identifier */
+	vci_strlen = strlen(CONFIG_BOOTP_VCI_STRING);
+	*e++ = vci_strlen;
+	memcpy(e, CONFIG_BOOTP_VCI_STRING, vci_strlen);
+	e += vci_strlen;
+#endif
+
 #if defined(CONFIG_BOOTP_VENDOREX)
 	if ((x = dhcp_vendorex_prep (e)))
 		return x - start;