Use gzip instead of zlib for Qualcomm decompression (#122)

theopolis · Aug 12, 2023 · f05ed14 · f05ed14
1 parent f289219
commit f05ed14
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Showing 3 changed files with 45 additions and 14 deletions.
diff --git a/uefi_firmware/guids/efiguids_qualcomm.py b/uefi_firmware/guids/efiguids_qualcomm.py
@@ -4,5 +4,5 @@
 """
 
 GUIDS = {
-    'QC_ZLIB_CUSTOM_DECOMPRESS_GUID': [0x1d301fe9, 0xbe79, 0x4353, 0x91, 0xc2, 0xd2, 0x3b, 0xc9, 0x59, 0xae, 0x0c],
+    'QC_GZIP_CUSTOM_DECOMPRESS_GUID': [0x1d301fe9, 0xbe79, 0x4353, 0x91, 0xc2, 0xd2, 0x3b, 0xc9, 0x59, 0xae, 0x0c],
 }
diff --git a/uefi_firmware/structs/uefi_structs.py b/uefi_firmware/structs/uefi_structs.py
@@ -29,13 +29,14 @@
 ]
 
 FIRMWARE_GUIDED_GUIDS = {
-    "LZMA_COMPRESSED":    "ee4e5898-3914-4259-9d6e-dc7bd79403cf",
-    "LZMA_COMPRESSED_HP": "0ed85e23-f253-413f-a03c-901987b04397",
-    "TIANO_COMPRESSED":   "a31280ad-481e-41b6-95e8-127f4c984779",
-    "FIRMWARE_VOLUME":    "24400798-3807-4a42-b413-a1ecee205dd8",
-    #"VOLUME_SECTION":    "367ae684-335d-4671-a16d-899dbfea6b88",
-    "STATIC_GUID":        "fc1bcdb0-7d31-49aa-936a-a4600d9dd083",
-    "ZLIB_COMPRESSED_QC": "1d301fe9-be79-4353-91c2-d23bc959ae0c"
+    "LZMA_COMPRESSED":     "ee4e5898-3914-4259-9d6e-dc7bd79403cf",
+    "LZMA_COMPRESSED_HP":  "0ed85e23-f253-413f-a03c-901987b04397",
+    "TIANO_COMPRESSED":    "a31280ad-481e-41b6-95e8-127f4c984779",
+    "FIRMWARE_VOLUME":     "24400798-3807-4a42-b413-a1ecee205dd8",
+    #"VOLUME_SECTION":     "367ae684-335d-4671-a16d-899dbfea6b88",
+    "STATIC_GUID":         "fc1bcdb0-7d31-49aa-936a-a4600d9dd083",
+    "GZIP_COMPRESSED_QC":  "1d301fe9-be79-4353-91c2-d23bc959ae0c",
+    "ZLIB_COMPRESSED_AMD": "ce3233f5-2cd6-4d87-9152-4a238bb6d1c4",
 }
 
 FIRMWARE_FREEFORM_GUIDS = {
@@ -197,3 +198,11 @@ class FirmwareVolumeType(ctypes.LittleEndianStructure):
         ("Reserved2",  uint8_t),
         ("Revision",   uint8_t)
     ]
+
+class EfiAmdZlibSectionHeader(ctypes.LittleEndianStructure):
+    _pack_ = 1
+    _fields_ = [
+        ("ZeroHeader", uint8_t * 0x14),
+        ("CompressedSize", uint32_t),
+        ("ZeroFooter", uint8_t * (0x100 - 0x14 - 4))   
+    ]
diff --git a/uefi_firmware/uefi.py b/uefi_firmware/uefi.py
@@ -4,9 +4,10 @@
 '''
 from __future__ import print_function
 
+import gzip
+import logging
 import os
 import struct
-import logging
 import zlib
 
 from .base import FirmwareObject, StructuredObject, RawObject, AutoRawObject
@@ -634,10 +635,19 @@ def decompress_guid(alg):
             status = decompress_guid(efi_compressor.LzmaDecompress)
         elif sguid(self.guid) == FIRMWARE_GUIDED_GUIDS["TIANO_COMPRESSED"]:
             status = decompress_guid(efi_compressor.TianoDecompress)
-        elif sguid(self.guid) == FIRMWARE_GUIDED_GUIDS["ZLIB_COMPRESSED_QC"]:
+        elif sguid(self.guid) == FIRMWARE_GUIDED_GUIDS["ZLIB_COMPRESSED_AMD"]:
+            body = self.preamble + self.data
+            if len(body) < 0x100:
+                dlog(self, sguid(self.guid), 'error, invalid AMD zlib section header size')
+                return False
+            header = EfiAmdZlibSectionHeader.from_buffer_copy(body[:0x100])
+            compressed_data = body[0x100:]
+            if len(compressed_data) != header.CompressedSize:
+                dlog(self, sguid(self.guid), 'error, invalid AMD zlib section header')
+                return False
             try:
-                data = zlib.decompress(self.preamble + self.data, 31)
-                if data is not None:
+                data = zlib.decompress(compressed_data)
+                if data:
                     self.subtype = 0
                     self.data = data
                     self.process_subsections()
@@ -646,7 +656,20 @@ def decompress_guid(alg):
                     dlog(self, sguid(self.guid), 'error, empty zlib decompress')
             except zlib.error as err:
                 status = False
-                dlog(self, sguid(self.guid), 'zlib error: ' + str(err))
+                dlog(self, sguid(self.guid), 'zlib error: %s' % str(err))
+        elif sguid(self.guid) == FIRMWARE_GUIDED_GUIDS["GZIP_COMPRESSED_QC"]:
+            try:
+                data = gzip.decompress(self.preamble + self.data)
+                if data:
+                    self.subtype = 0
+                    self.data = data
+                    self.process_subsections()
+                else:
+                    status = False
+                    dlog(self, sguid(self.guid), 'error, empty gzip decompress')
+            except Exception as err:
+                status = False
+                dlog(self, sguid(self.guid), 'gzip error: %s' % str(err))
         # Todo: check for processing required attribute
         elif sguid(self.guid) == FIRMWARE_GUIDED_GUIDS["STATIC_GUID"]:
             # Todo: verify this (FirmwareFile hack)
@@ -669,7 +692,6 @@ def decompress_guid(alg):
         if not status:
             dlog(self, sguid(self.guid), 'Could not parse GUID object')
         return status
-        pass
 
     def build(self, generate_checksum=False, debug=False):
         data = self._build_subsections(generate_checksum)