bios_extract: Handle Intel compressed option ROMs

bios_extract/src/bios_extract.c

@@ -127,7 +127,7 @@ int main(int argc, char *argv[])
 	int FileLength = 0;
 	uint32_t BIOSOffset = 0;
 	unsigned char *BIOSImage = NULL,
-		      IntelAMI[256], /* just 13 bytes needed, but LH5Decode overflows the buffer */
+		      IntelAMI[256], /* could be shorter if not for LH5Decode overflowing the buffer */
 		      *Buffer = NULL;
 	int fd;
 	uint32_t Offset1 = 0, Offset2 = 0;
@@ -199,30 +199,44 @@ int main(int argc, char *argv[])
 	}
 
 	/* Bruteforce Intel AMI Color fork LH5. */
-	for (i = 0; i < (FileLength - 10); i += 0x4000) {
-		BIOSOffset = i;
+	Offset2 = 1;
+	for (Offset1 = 0; Offset1 < (FileLength - 10); Offset1 += 0x4000) {
+		BIOSOffset = Offset1;
 CopyrightOffset:if ((LH5Decode(BIOSImage + BIOSOffset, FileLength - BIOSOffset, IntelAMI, 13) > -1) &&
-		    !memcmp(IntelAMI, "AMIBIOS(C)AMI", 13)) {
-			printf("Found Intel AMIBIOS.\nOffset: %X\n", BIOSOffset);
+		    (!memcmp(IntelAMI, "AMIBIOS(C)AMI", 13) || ((IntelAMI[0] == 0x55) && (IntelAMI[1] == 0xaa)))) {
+			if (Offset2 == 1) {
+				printf("Found potential Intel AMIBIOS.\n");
+				Offset2 = 86; /* magic exit code if no main body found */
+			}
 
-		    	Buffer = MMapOutputFile("intelbody.bin", 65536);
+			if (IntelAMI[0] == 0x55) {
+				len = IntelAMI[2] * 512;
+				sprintf((char *) IntelAMI, "intelopt_%05X.bin", BIOSOffset);
+			} else {
+				len = 65536;
+				sprintf((char *) IntelAMI, "intelbody_%05X.bin", BIOSOffset);
+				Offset2 = 0; /* main body found, all good */
+			}
+
+			printf("0x%05X                  ->   %s\t(%d bytes)\n",
+		       		BIOSOffset, IntelAMI, len);
+			Buffer = MMapOutputFile((char *) IntelAMI, len);
 			if (!Buffer)
 				return 1;
 
-			i = 65536;
+			i = len;
 			while ((LH5Decode(BIOSImage + BIOSOffset, FileLength - BIOSOffset, Buffer, i) == -1) &&
 				(i > 16))
 				i--;
 
-			munmap(Buffer, 65536);
-
-			return 0;
+			munmap(Buffer, len);
 		} else if (!(BIOSOffset & 0xff)) {
 			BIOSOffset += 0x44;
 			goto CopyrightOffset;
 		}
 	}
 
-	fprintf(stderr, "Error: Unable to detect BIOS Image type.\n");
-	return 1;
+	if (Offset2)
+		fprintf(stderr, "Error: Unable to detect BIOS Image type.\n");
+	return Offset2;
 }

biostools/extractors.py

@@ -327,6 +327,7 @@ class BIOSExtractor(Extractor):
 		except:
 			# Bad data can cause infinite loops.
 			proc = None
+			self.debug_print('Processing timed out on:', file_path)
 
 		# Assume failure if nothing was extracted. A lone boot block file also counts as a failure,
 		# as the extractors produce them before attempting to extract any actual BIOS modules.
@@ -336,11 +337,23 @@ class BIOSExtractor(Extractor):
 			return False
 		elif num_files_extracted == 1 and dest_dir_files[0] in ('amiboot.rom', 'ssboot.rom'):
 			# Remove boot block file so that the destination directory can be rmdir'd later.
-			try:
-				os.remove(os.path.join(dest_dir_0, dest_dir_files[0]))
-			except:
-				pass
+			util.remove_all(dest_dir_files, lambda x: os.path.join(dest_dir_0, x))
 			return False
+		elif proc and proc.returncode == 86:
+			# We received the magic exit code indicating the Intel pipeline found
+			# an option ROM but not the main body. This could indicate a non-Intel
+			# BIOS with LH5-compressed option ROMs. Check the files just in case.
+			have_intelopt = have_intelbody = False
+			for dest_dir_file in dest_dir_files:
+				if dest_dir_file[:9] == 'intelopt_':
+					have_intelopt = True
+				elif dest_dir_file[:10] == 'intelbody_':
+					have_intelbody = True
+					break
+			if have_intelopt and not have_intelbody:
+				# Remove all files so that the destination directory can be rmdir'd later.
+				util.remove_all(dest_dir_files, lambda x: os.path.join(dest_dir_0, x))
+				return False
 
 		# Extract Award BIOS PhoenixNet ROS filesystem.
 		if not proc or b'Found Award BIOS.' in proc.stdout:
@@ -1404,7 +1417,6 @@ class IntelExtractor(Extractor):
 						if bootblock_offset < 0:
 							bootblock_offset = 0
 					dest_offset += bootblock_offset
-					self.debug_print('bbo', hex(bootblock_offset), 'do', hex(dest_offset))
 				out_f.seek(dest_offset)
 
 				# Copy data.
@@ -1461,7 +1473,7 @@ class IntelExtractor(Extractor):
 					out_f = open(dest_file_path + '.padded', 'wb')
 
 					# Write padding.
-					self.debug_print('Padding by', hex(padding_size))
+					self.debug_print('Adding', padding_size, 'bytes of initial padding')
 					while padding_size > 0:
 						out_f.write(b'\xFF' * min(padding_size, 1048576))
 						padding_size -= 1048576