From 1a7ec07c28ee4830f14a0dfaa003aaa5f82eeffb Mon Sep 17 00:00:00 2001
From: Eve <eevvee@tuta.io>
Date: Tue, 13 Dec 2022 16:09:57 +0000
Subject: [PATCH] add linux.vmayarascan based on windows.vadtarascan

---
 .../framework/plugins/linux/vmayarascan.py    | 121 ++++++++++++++++++
 1 file changed, 121 insertions(+)
 create mode 100644 volatility3/framework/plugins/linux/vmayarascan.py

diff --git a/volatility3/framework/plugins/linux/vmayarascan.py b/volatility3/framework/plugins/linux/vmayarascan.py
new file mode 100644
index 000000000..e9482089a
--- /dev/null
+++ b/volatility3/framework/plugins/linux/vmayarascan.py
@@ -0,0 +1,121 @@
+# This file is Copyright 2019 Volatility Foundation and licensed under the Volatility Software License 1.0
+# which is available at https://www.volatilityfoundation.org/license/vsl-v1.0
+#
+
+from typing import Iterable, List, Tuple
+
+from volatility3.framework import interfaces, renderers
+from volatility3.framework.configuration import requirements
+from volatility3.framework.renderers import format_hints
+from volatility3.plugins import yarascan
+from volatility3.plugins.linux import pslist
+
+class VmaYaraScan(interfaces.plugins.PluginInterface):
+    """Scans all virtual memory areas for tasks using yara."""
+
+    _required_framework_version = (2, 4, 0)
+
+    @classmethod
+    def get_requirements(cls) -> List[interfaces.configuration.RequirementInterface]:
+        return [
+            requirements.ModuleRequirement(
+                name="kernel",
+                description="Linux kernel",
+                architectures=["Intel32", "Intel64"],
+            ),
+            requirements.BooleanRequirement(
+                name="wide",
+                description="Match wide (unicode) strings",
+                default=False,
+                optional=True,
+            ),
+            requirements.StringRequirement(
+                name="yara_rules", description="Yara rules (as a string)", optional=True
+            ),
+            requirements.URIRequirement(
+                name="yara_file", description="Yara rules (as a file)", optional=True
+            ),
+            # This additional requirement is to follow suit with upstream, who feel that compiled rules could potentially be used to execute malicious code
+            # As such, there's a separate option to run compiled files, as happened with yara-3.9 and later
+            requirements.URIRequirement(
+                name="yara_compiled_file",
+                description="Yara compiled rules (as a file)",
+                optional=True,
+            ),
+            requirements.IntRequirement(
+                name="max_size",
+                default=0x40000000,
+                description="Set the maximum size (default is 1GB)",
+                optional=True,
+            ),
+            requirements.PluginRequirement(
+                name="pslist", plugin=pslist.PsList, version=(2, 0, 0)
+            ),
+            requirements.VersionRequirement(
+                name="yarascanner", component=yarascan.YaraScanner, version=(2, 0, 0)
+            ),
+            requirements.ListRequirement(
+                name="pid",
+                element_type=int,
+                description="Process IDs to include (all other processes are excluded)",
+                optional=True,
+            ),
+        ]
+
+    def _generator(self):
+        kernel = self.context.modules[self.config["kernel"]]
+
+        rules = yarascan.YaraScan.process_yara_options(dict(self.config))
+
+        filter_func = pslist.PsList.create_pid_filter(self.config.get("pid", None))
+        for task in pslist.PsList.list_tasks(
+            context=self.context,
+            vmlinux_module_name=self.config["kernel"],
+            filter_func=filter_func,
+        ):
+            proc_layer_name = task.add_process_layer()
+            if not proc_layer_name:
+                continue
+
+            proc_layer = self.context.layers[proc_layer_name]
+            for offset, rule_name, name, value in proc_layer.scan(
+                context=self.context,
+                scanner=yarascan.YaraScanner(rules=rules),
+                sections=self.get_vma_maps(task),
+            ):
+                yield 0, (
+                    format_hints.Hex(offset),
+                    task.tgid,
+                    rule_name,
+                    name,
+                    value,
+                )
+
+    @staticmethod
+    def get_vma_maps(
+        task: interfaces.objects.ObjectInterface,
+    ) -> Iterable[Tuple[int, int]]:
+        """Creates a map of start/end addresses for each virtual memory area in a task.
+
+        Args:
+            task: The task object of which to read the vmas from
+
+        Returns:
+            An iterable of tuples containing start and end addresses for each descriptor
+        """
+        if task.mm:
+            for vma in task.mm.get_mmap_iter():
+                vm_size = vma.vm_end - vma.vm_start
+                yield (vma.vm_start, vm_size)
+
+    def run(self):
+        return renderers.TreeGrid(
+            [
+                ("Offset", format_hints.Hex),
+                ("PID", int),
+                ("Rule", str),
+                ("Component", str),
+                ("Value", bytes),
+            ],
+            self._generator(),
+        )