1 files changed, 143 insertions, 0 deletions
diff --git a/tools/inspect_os.py b/tools/inspect_os.py
new file mode 100644
index 0000000..ed4ee45
--- /dev/null
+++ b/tools/inspect_os.py
@@ -0,0 +1,143 @@
+import os
+import logging
+import re
+
+from glob import iglob
+from . import log
+
+__all__ = ["get_linux_os_info", "get_windows_os_info"]
+
+L = logging.getLogger(__name__)
+
+try:
+    from Registry import Registry  # type: ignore
+except ModuleNotFoundError:
+    L.error(
+        "You need to install the following package:\n"
+        "pip3 install python-registry"
+        )
+    raise
+
+
+@log
+def get_linux_os_info(path):
+    """Find and parse the os-release file.
+
+    See also:
+    https://www.freedesktop.org/software/systemd/man/os-release.html
+
+    Args:
+        path (str): Path to the mounted filesystem.
+
+    Returns:
+        Name and version of linux distribution as a dictionary. For example:
+        {'name': 'CentOS Linux', 'version': '6.0 (Final)'}
+    """
+    release_files = {}
+    for root, dirs, _ in os.walk(path):
+        if "etc" in dirs:
+            skip = False
+            for f in iglob(f"{root}/etc/*release"):
+                # Hack for immutable operating systems of Fedora.
+                if not os.path.exists(f):
+                    skip = True
+                    break
+                release_files[os.path.basename(f)] = f
+            if release_files and not skip:
+                break
+
+    if not release_files:
+        L.debug("no release file found")
+        return {}
+
+    L.debug("release files: %s", release_files)
+
+    name = version = ""
+    if "centos-release" in release_files:
+        L.debug("parsing %s", release_files["centos-release"])
+        # CentOS 6.* doesn't have os-release, but centos-release.
+        # For consistency, use always centos-release first.
+        with open(release_files["centos-release"]) as f:
+            # AlmaLinux 8.* and Rocky Linux 8.* also have centos-release.
+            if m := re.match(r"^(.*)\srelease\s(.*)$", f.read()):
+                name, version = m.groups()
+    elif "os-release" in release_files:
+        L.debug("parsing %s", release_files["os-release"])
+        with open(release_files["os-release"]) as f:
+            kv = {}
+            for line in f:
+                if not line or line.startswith("#") or "=" not in line:
+                    continue
+                k, v = line.split("=", 1)
+                kv[k] = v
+            name = kv.get("NAME", "")
+            version = kv.get("VERSION", kv.get("VERSION_ID", ""))
+    elif "system-release" in release_files:
+        # RedHat (RHEL) provides the redhat-release file. However, it does not
+        # seem to be reliable for determining which operating system it is.
+        # Therefore, for distributions such as Scientific Linux 6.* and
+        # Oracle Linux 6.*, use system-release instead.
+        L.debug("parsing %s", release_files["system-release"])
+        with open(release_files["system-release"]) as f:
+            if m := re.match(r"^(.*)\srelease\s(.*)$", f.read()):
+                name, version = m.groups()
+
+    if not name or not version:
+        return {}
+
+    name = name.strip().strip("'\"")
+    version = version.strip().strip("'\"")
+    return {"name": name, "version": version}
+
+
+@log
+def get_windows_os_info(path):
+    """Find and parse the software registry.
+
+    Args:
+        path (str): Path to the mounted filesystem.
+
+    Returns:
+        Name and version of windows distribution as a dictionary. For example:
+        {'name': 'Microsoft Windows XP', 'version': '5.1'}
+    """
+    software = None
+
+    locations = [
+        "WINDOWS/system32/config/software",  # xp
+        "Windows/System32/config/SOFTWARE",  # others
+    ]
+
+    for location in locations:
+        software_path = os.path.join(path, location)
+        if os.path.isfile(software_path):
+            software = software_path
+            break
+
+    if not software:
+        return {}
+
+    try:
+        registry = Registry.Registry(software)
+    except Exception as e:
+        L.error("failed to open registry file %s: %r", software, e)
+        return {}
+
+    hive_path = "Microsoft\\Windows NT\\CurrentVersion"
+    try:
+        key = registry.open(hive_path)
+    except Exception as e:
+        L.error("%s not found in %s: %r", hive_path, software, e)
+        return {}
+
+    name = version = ""
+    for k in key.values():
+        if k.name() == "ProductName":
+            name = k.value()
+        if k.name() == "CurrentVersion":
+            version = k.value()
+
+    if not name or not version:
+        return {}
+
+    return {"name": name, "version": version}