avoid using dmidecode

I didn't see any reason to depend on root privileges for dmidecode when you can
just fetch the data directly as an unprivileged user

Author: jasonwbarnett

Providers/Scripts/2.4x-2.5x/Scripts/nxOMSAutomationWorker.py

@@ -347,15 +347,9 @@ def get_optional_metadata():
     vm_id = unknown
     is_azure_vm = False
     try:
-        proc = subprocess.Popen(["sudo", "-u", AUTOMATION_USER, "python2", OMS_UTIL_FILE_PATH, "--dmidecode"],
-                                stdout=subprocess.PIPE, stderr=subprocess.PIPE)
-        dmidecode, error = proc.communicate()
-        if proc.returncode != 0 or not dmidecode:
-            raise Exception("Unable to invoke omsutil.py --dmidecode: %s" % error)
-        is_azure_vm = linuxutil.is_azure_vm(dmidecode)
-        if is_azure_vm:
+        if linuxutil.is_azure_vm():
             asset_tag = linuxutil.get_azure_vm_asset_tag()
-        vm_id = linuxutil.get_vm_unique_id_from_dmidecode(sys.byteorder, dmidecode)
+        vm_id = linuxutil.get_vm_unique_id()
     except Exception, e:
         log(INFO, "unable to get_optional_metadata: %s" % str(e))
 

Providers/Scripts/2.6x-2.7x/Scripts/nxOMSAutomationWorker.py

@@ -347,15 +347,9 @@ def get_optional_metadata():
     vm_id = unknown
     is_azure_vm = False
     try:
-        proc = subprocess.Popen(["sudo", "-u", AUTOMATION_USER, "python2", OMS_UTIL_FILE_PATH, "--dmidecode"],
-                                stdout=subprocess.PIPE, stderr=subprocess.PIPE)
-        dmidecode, error = proc.communicate()
-        if proc.returncode != 0 or not dmidecode:
-            raise Exception("Unable to invoke omsutil.py --dmidecode: %s" % error)
-        is_azure_vm = linuxutil.is_azure_vm(dmidecode)
-        if is_azure_vm:
+        if linuxutil.is_azure_vm():
             asset_tag = linuxutil.get_azure_vm_asset_tag()
-        vm_id = linuxutil.get_vm_unique_id_from_dmidecode(sys.byteorder, dmidecode)
+        vm_id = linuxutil.get_vm_unique_id()
     except Exception, e:
         log(INFO, "unable to get_optional_metadata: %s" % str(e))
 

Providers/Scripts/3.x/Scripts/nxOMSAutomationWorker.py

@@ -124,10 +124,10 @@ def Set_Marshall(ResourceSettings):
                 proxy_conf_path = PROXY_CONF_PATH_LEGACY
 
             workspace_id = settings.workspace_id.decode() if isinstance(settings.workspace_id, bytes) else settings.workspace_id
-            
+
             agent_service_zone = settings.azure_dns_agent_svc_zone
             azure_dns_agent_svc_zone = agent_service_zone.decode() if isinstance(agent_service_zone, bytes) else agent_service_zone
-            
+
             args = ["python3", REGISTRATION_FILE_PATH, "--register", "-w", workspace_id, "-a", agent_id,
                     "-c", OMS_CERTIFICATE_PATH, "-k", OMS_CERT_KEY_PATH, "-f", WORKING_DIRECTORY_PATH, "-s",
                     WORKER_STATE_DIR, "-e", azure_dns_agent_svc_zone, "-p", proxy_conf_path, "-g",
@@ -364,16 +364,9 @@ def get_optional_metadata():
     vm_id = unknown
     is_azure_vm = False
     try:
-        proc = subprocess.Popen(["sudo", "-u", AUTOMATION_USER, "python3", OMS_UTIL_FILE_PATH, "--dmidecode"],
-                                stdout=subprocess.PIPE, stderr=subprocess.PIPE)
-        dmidecode, error = proc.communicate()
-        dmidecode = dmidecode.decode("utf-8")
-        if proc.returncode != 0 or not dmidecode:
-            raise Exception("Unable to invoke omsutil.py --dmidecode: %s" % error.decode())
-        is_azure_vm = linuxutil.is_azure_vm(dmidecode)
-        if is_azure_vm:
+        if linuxutil.is_azure_vm():
             asset_tag = linuxutil.get_azure_vm_asset_tag()
-        vm_id = linuxutil.get_vm_unique_id_from_dmidecode(sys.byteorder, dmidecode)
+        vm_id = linuxutil.get_vm_unique_id()
     except Exception as e:
         log(INFO, "unable to get_optional_metadata: %s" % str(e))
 
@@ -620,7 +613,7 @@ def config_file_to_kv_pair(filename):
 def start_worker_manager_process(workspace_id):
     """
     Start the worker_manager_process
-    :param workspace_id: 
+    :param workspace_id:
     :return: the pid of the worker manager process
     """
     proc = subprocess.Popen(["sudo", "-u", AUTOMATION_USER, "python3", WORKER_MANAGER_START_PATH, OMS_CONF_FILE_PATH,
@@ -843,4 +836,4 @@ def log(level, message):
     try:
         LG().Log(logging.getLevelName(level), message)
     except:
-        pass
+        pass

Providers/nxOMSAutomationWorker/automationworker/3.x/scripts/onboarding3.py

@@ -94,7 +94,7 @@ def generate_hmac(str_to_sign, secret):
     secret = secret.encode('utf-8')
     cmd = ['echo -n "' + str(message.decode("utf-8")) + '" | openssl dgst -sha256 -binary -hmac "' + str(secret.decode("utf-8")) + '"']
     process, signed_message, error = linuxutil.popen_communicate(cmd, shell=True)
-    
+
     error = error.decode() if isinstance(error, bytes) else error
     if process.returncode != 0:
         raise Exception("Unable to generate signature. " + str(error))
@@ -266,17 +266,15 @@ def register(options):
     vm_id = unknown
     is_azure_vm = False
     try:
-        dmidecode = invoke_dmidecode()
-        is_azure_vm = linuxutil.is_azure_vm(dmidecode)
-        if is_azure_vm:
+        if linuxutil.is_azure_vm():
             asset_tag = linuxutil.get_azure_vm_asset_tag()
         else:
             asset_tag = False
-        vm_id = linuxutil.get_vm_unique_id_from_dmidecode(sys.byteorder, dmidecode)
+        vm_id = linuxutil.get_vm_unique_id()
     except Exception as e:
         print (str(e))
         pass
-    
+
     # generate payload for registration request
     date = datetime.datetime.utcnow().isoformat() + "0-00:00"
     payload = {'RunbookWorkerGroup': hybrid_worker_group_name,
@@ -425,4 +423,3 @@ def environment_prerequisite_validation():
     nxautomation_group_name = "nxautomation"
     if linuxutil.is_existing_group(omiusers_group_name) is False:
         raise Exception("Missing group : " + nxautomation_group_name + ".")
-

Providers/nxOMSAutomationWorker/automationworker/3.x/worker/linuxutil.py

@@ -90,39 +90,28 @@ def get_azure_vm_asset_tag():
     return "7783-7084-3265-9085-8269-3286-77"
 
 
-def is_azure_vm(dmidecode_output):
-    """Detects azure vm from dmidecode output.
-
-    Note : is an asset tag "7783-7084-3265-9085-8269-3286-77" is present then this is an azure vm.
-
-    Returns:
-        bool, true if the host is an azure vm.
-    """
-    #print("linux util dmidecode : "+ str(dmidecode_output))
-    asset_tags = re.findall(get_azure_vm_asset_tag(), dmidecode_output)
-
-    for tag in asset_tags:
-        if get_azure_vm_asset_tag() in tag:
-            return True
-
-    return False
+def is_azure_vm():
+    try:
+        with open('/sys/devices/virtual/dmi/id/chassis_asset_tag', 'r') as file:
+            return file.read().strip() == get_azure_vm_asset_tag()
+    except (FileNotFoundError, PermissionError):
+        print("File not found or permission denied")
+        return False
 
 
-def get_vm_unique_id_from_dmidecode(byteorder, dmidecode_output):
+def get_vm_unique_id():
     """Extract the host UUID from dmidecode output.
 
     Returns:
         string, the host UUID.
     """
-    uuid_prefix = "UUID: "
-    uuids = re.findall(uuid_prefix + "[A-Z0-9]{8}-[A-Z0-9]{4}-[A-Z0-9]{4}-[A-Z0-9]{4}-[A-Z0-9]{12}",
-                       dmidecode_output.upper())
-    if len(uuids) < 1:
+    byteorder = sys.byteorder
+    try:
+        with open('/sys/devices/virtual/dmi/id/product_uuid', 'r') as file:
+            uuid = file.read().strip().lower()
+    except (FileNotFoundError, PermissionError):
         raise Exception("No host UUID found.")
 
-    # if multiple UUIDs are found take the first one
-    uuid = uuids[0].split(uuid_prefix)[1].strip()
-
     # azure uuids are big endian
     if byteorder == "big":
         return uuid
@@ -139,8 +128,8 @@ def get_vm_unique_id_from_dmidecode(byteorder, dmidecode_output):
 def convert_to_big_endian(little_endian_value):
     """Converts the little endian representation of the value into a big endian representation of the value"""
     """
-    Little and big endian are two ways of storing multibyte data-types ( int, float, etc). 
-    In little endian machines, last byte of binary representation of the multibyte data-type is stored first. 
+    Little and big endian are two ways of storing multibyte data-types ( int, float, etc).
+    In little endian machines, last byte of binary representation of the multibyte data-type is stored first.
     On the other hand, in big endian machines, first byte of binary representation of the multibyte data-type is stored first.
     """
     codecs_decoded =  codecs.decode(little_endian_value, "hex")

Providers/nxOMSAutomationWorker/automationworker/scripts/onboarding2.py

@@ -246,7 +246,7 @@ def register(options):
     if os.path.isdir(DIY_STATE_PATH) is False:
         try:
             os.makedirs(DIY_STATE_PATH)
-        except Exception, ex:            
+        except Exception, ex:
             print("Registration unsuccessful.")
             print("Cannot create directory for certs/conf. Because of the following exception : " + str(ex))
             return
@@ -259,13 +259,11 @@ def register(options):
     vm_id = unknown
     is_azure_vm = False
     try:
-        dmidecode = invoke_dmidecode()
-        is_azure_vm = linuxutil.is_azure_vm(dmidecode)
-        if is_azure_vm:
+        if linuxutil.is_azure_vm():
             asset_tag = linuxutil.get_azure_vm_asset_tag()
         else:
             asset_tag = False
-        vm_id = linuxutil.get_vm_unique_id_from_dmidecode(sys.byteorder, dmidecode)
+        vm_id = linuxutil.get_vm_unique_id()
     except Exception, e:
         print str(e)
         pass
@@ -421,5 +419,3 @@ def environment_prerequisite_validation():
     nxautomation_group_name = "nxautomation"
     if linuxutil.is_existing_group(omiusers_group_name) is False:
         raise Exception("Missing group : " + nxautomation_group_name + ".")
-
-

Providers/nxOMSAutomationWorker/automationworker/worker/linuxutil.py

@@ -104,21 +104,19 @@ def is_azure_vm(dmidecode_output):
     return False
 
 
-def get_vm_unique_id_from_dmidecode(byteorder, dmidecode_output):
+def get_vm_unique_id():
     """Extract the host UUID from dmidecode output.
 
     Returns:
         string, the host UUID.
     """
-    uuid_prefix = "UUID: "
-    uuids = re.findall(uuid_prefix + "[A-Z0-9]{8}-[A-Z0-9]{4}-[A-Z0-9]{4}-[A-Z0-9]{4}-[A-Z0-9]{12}",
-                       dmidecode_output.upper())
-    if len(uuids) < 1:
+    byteorder = sys.byteorder
+    try:
+        with open('/sys/devices/virtual/dmi/id/product_uuid', 'r') as file:
+            uuid = file.read().strip().lower()
+    except (FileNotFoundError, PermissionError):
         raise Exception("No host UUID found.")
 
-    # if multiple UUIDs are found take the first one
-    uuid = uuids[0].split(uuid_prefix)[1].strip()
-
     # azure uuids are big endian
     if byteorder == "big":
         return uuid