Add Linux Variable Writing Script

.cspell.json

@@ -125,6 +125,9 @@
       "profilenames",
       "profileid",
       "profileids",
-      "prettyname"
+      "prettyname",
+      "efivars",
+      "efivarfs",
+      "chattr"
   ]
 }

SetupDataPkg/SetupDataPkg.ci.yaml

@@ -91,7 +91,10 @@
           "dmpstore",
           "mschange",
           "DDTHH",
-          "prettyname"
+          "prettyname",
+          "efivars",
+          "efivarfs",
+          "chattr"
         ],                           # words to extend to the dictionary for this package
         "IgnoreStandardPaths": [],   # Standard Plugin defined paths that should be ignore
         "AdditionalIncludePaths": [] # Additional paths to spell check (wildcards supported)

SetupDataPkg/Tools/ReadUefiVarsToConfVarList.py

@@ -12,7 +12,10 @@
 import struct
 import uuid
 import ctypes
-from SettingSupport.UefiVariablesSupportLib import UefiVariable
+if os.name == 'nt':
+    from SettingSupport.UefiVariablesSupportLib import UefiVariable
+else:
+    from SettingSupport.UefiVariablesSupportLinuxLib import UefiVariable
 from VariableList import Schema, UEFIVariable, create_vlist_buffer
 
 
@@ -53,7 +56,7 @@ def option_parser():
 # array
 #
 def read_variable_into_variable_list(uefi_var, name, namespace):
-    (rc, var, _) = uefi_var.GetUefiVar(name, namespace)
+    (rc, var) = uefi_var.GetUefiVar(name, namespace)
     if rc != 0:
         if rc != UefiVariable.ERROR_ENVVAR_NOT_FOUND:
             # only log the errors other than EFI_NOT_FOUND, because not found is normal in this case...
@@ -78,7 +81,7 @@ def main():
         ret = b''
         if arguments.configuration_file is None:
             # Read all the variables
-            (rc, efi_var_names, error_string) = UefiVar.GetUefiAllVarNames()
+            (rc, efi_var_names) = UefiVar.GetUefiAllVarNames()
             if rc != 0:
                 logging.error(f"Error returned from GetUefiAllVarNames: {rc}")
 
@@ -117,9 +120,14 @@ def main():
     console.setLevel(logging.CRITICAL)
 
     # check the privilege level and report error
-    if not ctypes.windll.shell32.IsUserAnAdmin():
-        print("Administrator privilege required. Please launch from an Administrator privilege level.")
-        sys.exit(1)
+    if os.name == 'nt':
+        if not ctypes.windll.shell32.IsUserAnAdmin():
+            print("Administrator privilege required. Please launch from an Administrator privilege level.")
+            sys.exit(1)
+    else:
+        if os.geteuid() != 0:
+            print("Root permission required, please run script with sudo.")
+            sys.exit(1)
 
     # call main worker function
     retcode = main()

SetupDataPkg/Tools/SettingSupport/UefiVariablesSupportLib.py

@@ -10,7 +10,6 @@
     c_wchar_p,
     c_void_p,
     c_int,
-    c_char,
     create_string_buffer,
     WinError,
     pointer
@@ -90,27 +89,6 @@ def __init__(self):
             )
             pass
 
-    #
-    # Helper function to create buffer for var read/write
-    #
-    def CreateBuffer(self, init, size=None):
-        """CreateBuffer(aString) -> character array
-        CreateBuffer(anInteger) -> character array
-        CreateBuffer(aString, anInteger) -> character array
-        """
-        if isinstance(init, str):
-            if size is None:
-                size = len(init) + 1
-            buftype = c_char * size
-            buf = buftype()
-            buf.value = init
-            return buf
-        elif isinstance(init, int):
-            buftype = c_char * init
-            buf = buftype()
-            return buf
-        raise TypeError(init)
-
     #
     # Function to get variable
     # return a tuple of error code and variable data as string
@@ -135,8 +113,8 @@ def GetUefiVar(self, name, guid):
                 )
                 logging.error(WinError())
             if efi_var is None:
-                return (err, None, WinError(err))
-        return (err, efi_var[:length], WinError(err))
+                return (err, None)
+        return (err, efi_var[:length])
 
     #
     # Function to get all variable names
@@ -176,8 +154,8 @@ def GetUefiAllVarNames(self):
             logging.error(
                 "EnumerateFirmwareEnvironmentVariable failed (GetLastError = 0x%x)" % status
             )
-            return (status, None, WinError(status))
-        return (status, efi_var_names, None)
+            return (status, None)
+        return (status, efi_var_names)
 
     #
     # Function to set variable
@@ -186,7 +164,6 @@ def GetUefiAllVarNames(self):
     def SetUefiVar(self, name, guid, var=None, attrs=None):
         var_len = 0
         err = 0
-        error_string = None
         if var is None:
             var = bytes(0)
         else:
@@ -221,5 +198,4 @@ def SetUefiVar(self, name, guid, var=None, attrs=None):
                 "SetFirmwareEnvironmentVariable failed (GetLastError = 0x%x)" % err
             )
             logging.error(WinError())
-            error_string = WinError(err)
-        return (success, err, error_string)
+        return success

SetupDataPkg/Tools/SettingSupport/UefiVariablesSupportLinuxLib.py

@@ -0,0 +1,143 @@
+# @file
+#
+# Python lib to support Reading and writing UEFI variables from Linux
+#
+#
+# Copyright (c), Microsoft Corporation
+# SPDX-License-Identifier: BSD-2-Clause-Patent
+#
+# GetUefiAllVarNames is based on information from
+# https://github.com/awslabs/python-uefivars/blob/main/pyuefivars/efivarfs.py
+#
+# Copyright Amazon.com, Inc. or its affiliates. All Rights Reserved.
+# SPDX-License-Identifier: MIT
+
+import os
+import uuid
+import struct
+
+from ctypes import (
+    create_string_buffer
+)
+
+EFI_VAR_MAX_BUFFER_SIZE = 1024 * 1024
+
+
+class UefiVariable(object):
+    ERROR_ENVVAR_NOT_FOUND = 0xcb
+
+    def __init__(self):
+        pass
+
+    #
+    # Function to get variable
+    # return a tuple of error code and variable data as string
+    #
+    def GetUefiVar(self, name, guid):
+        # success
+        err = 0
+        # the variable name is VariableName-Guid
+        path = '/sys/firmware/efi/efivars/' + name + '-%s' % guid
+
+        if not os.path.exists(path):
+            err = UefiVariable.ERROR_ENVVAR_NOT_FOUND
+            return (err, None)
+
+        efi_var = create_string_buffer(EFI_VAR_MAX_BUFFER_SIZE)
+        with open(path, 'rb') as fd:
+            efi_var = fd.read()
+
+        return (err, efi_var)
+
+    #
+    # Function to get all variable names
+    # return a tuple of error code and variable names byte array formatted as:
+    #
+    # typedef struct _VARIABLE_NAME {
+    #   ULONG NextEntryOffset;
+    #   GUID VendorGuid;
+    #   WCHAR Name[ANYSIZE_ARRAY];
+    # } VARIABLE_NAME, *PVARIABLE_NAME;
+    #
+    def GetUefiAllVarNames(self):
+        # success
+        status = 0
+
+        # implementation borrowed from https://github.com/awslabs/python-uefivars/blob/main/pyuefivars/efivarfs.py
+        path = '/sys/firmware/efi/efivars'
+        if not os.path.exists(path):
+            status = UefiVariable.ERROR_ENVVAR_NOT_FOUND
+            return (status, None)
+
+        vars = os.listdir(path)
+
+        # get the total buffer length, converting to unicode
+        length = 0
+        offset = 0
+        for var in vars:
+            split_string = var.split('-')
+            name = '-'.join(split_string[:-5])
+            name = name.encode('utf-16-le')
+            name_len = len(name)
+            length += (4 + 16 + name_len)
+
+        efi_var_names = create_string_buffer(length)
+
+        for var in vars:
+            # efivarfs stores vars as NAME-GUID
+            split_string = var.split('-')
+            try:
+                # GUID is last 5 elements of split_string
+                guid = uuid.UUID('-'.join(split_string[-5:])).bytes_le
+            except ValueError:
+                raise Exception(f'Could not parse "{var}"')
+
+            # the other part is the name
+            name = '-'.join(split_string[:-5])
+            name = name.encode('utf-16-le')
+            name_len = len(name)
+
+            # NextEntryOffset
+            struct.pack_into('<I', efi_var_names, offset, 4 + 16 + name_len)
+            offset += 4
+
+            # VendorGuid
+            struct.pack_into('=16s', efi_var_names, offset, guid)
+            offset += 16
+
+            # Name
+            struct.pack_into(f'={name_len}s', efi_var_names, offset, name)
+            offset += name_len
+
+        return (status, efi_var_names)
+
+    #
+    # Function to set variable
+    # return a tuple of boolean status, error_code, error_string (None if not error)
+    #
+    def SetUefiVar(self, name, guid, var=None, attrs=None):
+        success = 0  # Fail
+
+        # There is a null terminator at the end of the name
+        path = '/sys/firmware/efi/efivars/' + name[:-1] + '-' + str(guid)
+        if var is None:
+            # we are deleting the variable
+            if (os.path.exists(path)):
+                os.remove(path)
+                success = 1  # expect non-zero success
+            return success
+
+        if attrs is None:
+            attrs = 0x7
+
+        # if the file exists, remove the immutable flag
+        if (os.path.exists(path)):
+            os.system('sudo chattr -i ' + path)
+
+        with open(path, 'wb') as fd:
+            # var data is attribute (UINT32) followed by data
+            packed = struct.pack('=I', attrs)
+            packed += var
+            fd.write(packed)
+
+        return 1

SetupDataPkg/Tools/WriteConfVarListToUefiVars.py

@@ -12,7 +12,10 @@
 import struct
 import uuid
 import ctypes
-from SettingSupport.UefiVariablesSupportLib import UefiVariable
+if os.name == 'nt':
+    from SettingSupport.UefiVariablesSupportLib import UefiVariable
+else:
+    from SettingSupport.UefiVariablesSupportLinuxLib import UefiVariable
 
 gEfiGlobalVariableGuid = "8BE4DF61-93CA-11D2-AA0D-00E098032B8C"
 
@@ -93,7 +96,7 @@ def extract_single_var_from_file_and_write_nvram(var):
         logging.debug(f"Found Variable: {VarName} {Guid} {Attributes}")
 
         UefiVar = UefiVariable()
-        (rc, err, error_string) = UefiVar.SetUefiVar(
+        rc = UefiVar.SetUefiVar(
             VarName,
             Guid,
             Data,
@@ -136,9 +139,14 @@ def main():
     console.setLevel(logging.CRITICAL)
 
     # check the privilege level and report error
-    if not ctypes.windll.shell32.IsUserAnAdmin():
-        print("Administrator privilege required. Please launch from an Administrator privilege level.")
-        sys.exit(1)
+    if os.name == 'nt':
+        if not ctypes.windll.shell32.IsUserAnAdmin():
+            print("Administrator privilege required. Please launch from an Administrator privilege level.")
+            sys.exit(1)
+    else:
+        if os.geteuid() != 0:
+            print("Root permission required, please run script with sudo.")
+            sys.exit(1)
 
     # call main worker function
     retcode = main()