kdump-Remote-SSH-Configurations (#3400)

What I did
Added remote kdump functionality using SSH in SONiC.

How I did it
I added two new commands and two options to configure the kdump remote ssh feature.

How to verify it
Upon kernel crash, kdump will transfer the crash report files to the ssh server.

Author: Ghulam-Bahoo

config/kdump.py

@@ -1,18 +1,18 @@
 import sys
-
 import click
+import os
 from utilities_common.cli import AbbreviationGroup, pass_db
-
-
+from ipaddress import ip_address, AddressValueError
+import re
 #
 # 'kdump' group ('sudo config kdump ...')
 #
+
 @click.group(cls=AbbreviationGroup, name="kdump")
 def kdump():
     """Configure the KDUMP mechanism"""
     pass
 
-
 def check_kdump_table_existence(kdump_table):
     """Checks whether the 'KDUMP' table is configured in Config DB.
 
@@ -32,40 +32,46 @@ def check_kdump_table_existence(kdump_table):
         sys.exit(2)
 
 
+def echo_reboot_warning():
+    """Prints the warning message about reboot requirements."""
+    click.echo("KDUMP configuration changes may require a reboot to take effect.")
+    click.echo("Save SONiC configuration using 'config save' before issuing the reboot command.")
 #
 # 'disable' command ('sudo config kdump disable')
 #
-@kdump.command(name="disable", short_help="Disable the KDUMP mechanism")
+
+
+@kdump.command(name="disable", help="Disable the KDUMP mechanism")
 @pass_db
 def kdump_disable(db):
     """Disable the KDUMP mechanism"""
     kdump_table = db.cfgdb.get_table("KDUMP")
     check_kdump_table_existence(kdump_table)
 
     db.cfgdb.mod_entry("KDUMP", "config", {"enabled": "false"})
-    click.echo("KDUMP configuration changes may require a reboot to take effect.")
-    click.echo("Save SONiC configuration using 'config save' before issuing the reboot command.")
-
+    echo_reboot_warning()
 
 #
 # 'enable' command ('sudo config kdump enable')
 #
-@kdump.command(name="enable", short_help="Enable the KDUMP mechanism")
+
+
+@kdump.command(name="enable", help="Enable the KDUMP mechanism")
 @pass_db
 def kdump_enable(db):
     """Enable the KDUMP mechanism"""
     kdump_table = db.cfgdb.get_table("KDUMP")
     check_kdump_table_existence(kdump_table)
 
     db.cfgdb.mod_entry("KDUMP", "config", {"enabled": "true"})
-    click.echo("KDUMP configuration changes may require a reboot to take effect.")
-    click.echo("Save SONiC configuration using 'config save' before issuing the reboot command.")
-
+    echo_reboot_warning()
 
 #
 # 'memory' command ('sudo config kdump memory ...')
 #
-@kdump.command(name="memory", short_help="Configure the memory for KDUMP mechanism")
+
+
+@kdump.command(name="memory", help="Configure the memory for KDUMP mechanism")
 @click.argument('kdump_memory', metavar='<kdump_memory>', required=True)
 @pass_db
 def kdump_memory(db, kdump_memory):
@@ -74,14 +80,14 @@ def kdump_memory(db, kdump_memory):
     check_kdump_table_existence(kdump_table)
 
     db.cfgdb.mod_entry("KDUMP", "config", {"memory": kdump_memory})
-    click.echo("KDUMP configuration changes may require a reboot to take effect.")
-    click.echo("Save SONiC configuration using 'config save' before issuing the reboot command.")
-
+    echo_reboot_warning()
 
 #
-# 'num_dumps' command ('sudo config keump num_dumps ...')
+# 'num_dumps' command ('sudo config kdump num_dumps ...')
 #
-@kdump.command(name="num_dumps", short_help="Configure the maximum dump files of KDUMP mechanism")
+
+
+@kdump.command(name="num_dumps", help="Configure the maximum dump files of KDUMP mechanism")
 @click.argument('kdump_num_dumps', metavar='<kdump_num_dumps>', required=True, type=int)
 @pass_db
 def kdump_num_dumps(db, kdump_num_dumps):
@@ -90,3 +96,160 @@ def kdump_num_dumps(db, kdump_num_dumps):
     check_kdump_table_existence(kdump_table)
 
     db.cfgdb.mod_entry("KDUMP", "config", {"num_dumps": kdump_num_dumps})
+    echo_reboot_warning()
+
+
+@kdump.command(name="remote", help="Configure the remote enable/disable for KDUMP mechanism")
+@click.argument('action', metavar='<enable/disable>', required=True, type=click.STRING)  # Corrected this line
+@pass_db
+def remote(db, action):
+    """Enable or disable remote kdump feature"""
+    kdump_table = db.cfgdb.get_table("KDUMP")
+    check_kdump_table_existence(kdump_table)
+
+    # Get the current status of the remote feature as string
+    current_status = kdump_table["config"].get("remote", "false").lower()
+
+    if action.lower() == 'enable':
+        if current_status == "true":
+            click.echo("Remote kdump feature is already enabled.")
+        else:
+            db.cfgdb.mod_entry("KDUMP", "config", {"remote": "true"})
+            click.echo("Remote kdump feature enabled.")
+            echo_reboot_warning()
+    elif action.lower() == 'disable':
+        if current_status == "false":
+            click.echo("Remote kdump feature is already disabled.")
+        else:
+            db.cfgdb.mod_entry("KDUMP", "config", {"remote": "false"})
+            click.echo("Remote kdump feature disabled.")
+            echo_reboot_warning()
+    else:
+        click.echo("Invalid action. Use 'enable' or 'disable'.")
+
+
+@kdump.group(name="add", help="Add configuration items to KDUMP")
+def add():
+    """Group of commands to add configuration items to KDUMP"""
+    pass
+
+
+@add.command(name="ssh_string", help="Add an SSH string to the KDUMP configuration")
+@click.argument('ssh_string', metavar='<ssh_key>', required=True)
+@pass_db
+def add_ssh_key(db, ssh_string):
+    """Add an SSH string to KDUMP configuration"""
+
+    def is_valid_ssh_key(ssh_string):
+        """Validate the SSH key format"""
+        # Check if it contains username and hostname/IP (format: username@host)
+        if "@" not in ssh_string:
+            return "Invalid format. SSH key must be in 'username@host' format."
+
+        username, host = ssh_string.split("@", 1)
+
+        # Validate username
+        if not username or not username.isalnum():
+            return "Invalid username. Ensure it contains only alphanumeric characters."
+
+        # Validate host (IP or hostname)
+        try:
+            # Check if it's a valid IP address
+            ip_address(host)
+        except AddressValueError:
+            # If not an IP, validate hostname
+            hostname_regex = r'^[a-zA-Z0-9.-]+$'
+            if not re.match(hostname_regex, host) or host.startswith('-') or host.endswith('-'):
+                return "Invalid host. Must be a valid IP or hostname."
+
+        return None  # Validation successful
+
+    kdump_table = db.cfgdb.get_table("KDUMP")
+    check_kdump_table_existence(kdump_table)
+    current_status = kdump_table["config"].get("remote", "false").lower()
+
+    if current_status == 'false':
+        click.echo("Remote feature is not enabled. Please enable the remote feature first.")
+        return
+
+    # Validate SSH key
+    validation_error = is_valid_ssh_key(ssh_string)
+    if validation_error:
+        click.echo(f"Error: {validation_error}")
+        return
+
+    # Add or update the 'ssh_key' entry in the KDUMP table
+    db.cfgdb.mod_entry("KDUMP", "config", {"ssh_string": ssh_string})
+    click.echo(f"SSH string added to KDUMP configuration: {ssh_string}")
+
+
+@add.command(name="ssh_path", help="Add an SSH path to the KDUMP configuration")
+@click.argument('ssh_path', metavar='<ssh_path>', required=True)
+@pass_db
+def add_ssh_path(db, ssh_path):
+    """Add an SSH path to KDUMP configuration"""
+
+    def is_valid_ssh_path(ssh_path):
+        """Validate the SSH path"""
+        # Check if the path is absolute
+        if not os.path.isabs(ssh_path):
+            return "Invalid path. SSH path must be an absolute path."
+
+        # (Optional) Check if the path exists on the system
+        if not os.path.exists(ssh_path):
+            return f"Invalid path. The path '{ssh_path}' does not exist."
+
+        return None  # Validation successful
+
+    kdump_table = db.cfgdb.get_table("KDUMP")
+    check_kdump_table_existence(kdump_table)
+    current_status = kdump_table["config"].get("remote", "false").lower()
+    if current_status == 'false':
+        click.echo("Remote feature is not enabled. Please enable the remote feature first.")
+        return
+
+    # Validate SSH path
+    validation_error = is_valid_ssh_path(ssh_path)
+    if validation_error:
+        click.echo(f"Error: {validation_error}")
+        return
+
+    # Add or update the 'ssh_path' entry in the KDUMP table
+    db.cfgdb.mod_entry("KDUMP", "config", {"ssh_path": ssh_path})
+    click.echo(f"SSH path added to KDUMP configuration: {ssh_path}")
+
+
+@kdump.group(name="remove", help="remove configuration items to KDUMP")
+def remove():
+    """Group of commands to remove configuration items to KDUMP"""
+    pass
+
+
+@remove.command(name="ssh_string", help="Remove the SSH string from the KDUMP configuration")
+@pass_db
+def remove_ssh_string(db):
+    """Remove the SSH string from KDUMP configuration"""
+    kdump_table = db.cfgdb.get_table("KDUMP")
+    check_kdump_table_existence(kdump_table)
+
+    # Check if ssh_string exists
+    if "ssh_string" in kdump_table["config"]:
+        db.cfgdb.mod_entry("KDUMP", "config", {"ssh_string": None})
+        click.echo("SSH string removed from KDUMP configuration.")
+    else:
+        click.echo("SSH string not found in KDUMP configuration.")
+
+
+@remove.command(name="ssh_path", help="Remove the SSH path from the KDUMP configuration")
+@pass_db
+def remove_ssh_path(db):
+    """Remove the SSH path from KDUMP configuration"""
+    kdump_table = db.cfgdb.get_table("KDUMP")
+    check_kdump_table_existence(kdump_table)
+
+    # Check if ssh_string exists
+    if "ssh_path" in kdump_table["config"]:
+        db.cfgdb.mod_entry("KDUMP", "config", {"ssh_path": None})
+        click.echo("SSH path removed from KDUMP configuration.")
+    else:
+        click.echo("SSH path not found in KDUMP configuration.")