ich9gen: make it possible for user to change the Gbe MAC address

Example: ./ich9gen --macaddress AA:BB:CC:DD:EE:FF

1 files changed, 53 insertions, 1 deletions

diff --git a/resources/utilities/ich9deblob/src/ich9gen.c b/resources/utilities/ich9deblob/src/ich9gen.c
index 583957e..81fd182 100644
--- a/resources/utilities/ich9deblob/src/ich9gen.c
+++ b/resources/utilities/ich9deblob/src/ich9gen.c
@@ -22,6 +22,9 @@
 
 int main(int argc, char *argv[]) 
 {
+	int i, j;
+	unsigned char customMacAddress[6]; /* Only set/used if the user wants to */
+	
 	struct GBEREGIONRECORD_8K gbeStruct8k = generatedGbeStruct8k();
 	struct DESCRIPTORREGIONRECORD descriptorStruct4M = generatedDescriptorStructRom4M();
 	struct DESCRIPTORREGIONRECORD descriptorStruct8M = generatedDescriptorStructRom8M();
@@ -41,7 +44,56 @@ int main(int argc, char *argv[])
 	
 	/*
 	 * ------------------------------------------------------------------
-	 * Down to business
+	 * Arguments given on the terminal
+	 * ------------------------------------------------------------------
+	 */
+	 
+
+	if(argc==3) {
+		
+		/* If user provides their own MAC address, it will be used.
+		 * Otherwise, ich9gen will simply use the default one. 
+		 * 
+		 * However, if the user provides an invalid MAC address, then ich9gen
+		 * will exit. */
+		if(0==strcmp(argv[1],"--macaddress")) {
+			/* 6 hex chars format (example): AA:BB:CC:DD:EE:FF */
+			if (strlen(argv[2]) != 17) {
+				printf("ich9gen: invalid mac address format (wrong length)\n");
+				return 1;
+			}
+			for(i=2; i<14; i+=3) {
+				if(argv[2][i]!=':') {
+					printf("ich9gen: invalid mac address format (non-color characters used as spacing)\n");
+					return 1;
+				}
+			}
+			for(i=0; i<6; i++) {
+				/* Go through each nibble of the byte */
+				for(j=0; j<2; j++) {
+					if(argv[2][(i*3)+j]>='a' && argv[2][(i*3)+j]<='f')
+						customMacAddress[i] |= (argv[2][(i*3)+j] - 87) << ((j^1) << 2);
+					else if(argv[2][(i*3)+j]>='A' && argv[2][(i*3)+j]<='F')
+						customMacAddress[i] |= (argv[2][(i*3)+j] - 55) << ((j^1) << 2);
+					else if(argv[2][(i*3)+j]>='0' && argv[2][(i*3)+j]<='9')
+						customMacAddress[i] |= (argv[2][(i*3)+j] - 48) << ((j^1) << 2);
+					else {
+						printf("ich9gen: invalid mac address format (non-hex characters)\n");
+						return 1;
+					}
+				}
+			}
+			/* Now that the new MAC address is verified, use it */
+			memcpy(&gbeStruct8k.main.macAddress, &customMacAddress, 6); /* Update MAC address in main Gbe */
+			gbeStruct8k.main.checkSum = gbeGetChecksumFrom4kStruct(gbeStruct8k.main, GBECHECKSUMTOTAL); /* Fix the checksum */
+			memcpy(&gbeStruct8k.backup, &gbeStruct8k.main, GBEREGIONSIZE_4K); /* Copy to the backup */
+		}
+		
+	}
+	
+	/*
+	 * ------------------------------------------------------------------
+	 * Generate the 12KiB files, ready to be used in a libreboot image
 	 * ------------------------------------------------------------------
 	 */