Edit file

File name : linux_sysctl.py

Content :""" Module for viewing and modifying sysctl parameters """ import logging import os import re import salt.utils.data import salt.utils.files import salt.utils.stringutils import salt.utils.systemd from salt.exceptions import CommandExecutionError log = logging.getLogger(__name__) # Define the module's virtual name __virtualname__ = "sysctl" # TODO: Add unpersist() to remove either a sysctl or sysctl/value combo from # the config def __virtual__(): """ Only run on Linux systems """ if __grains__["kernel"] != "Linux": return ( False, "The linux_sysctl execution module cannot be loaded: only available on" " Linux systems.", ) return __virtualname__ def default_config(): """ Linux hosts using systemd 207 or later ignore ``/etc/sysctl.conf`` and only load from ``/etc/sysctl.d/*.conf``. This function will do the proper checks and return a default config file which will be valid for the Minion. Hosts running systemd >= 207 will use ``/etc/sysctl.d/99-salt.conf``. CLI Example: .. code-block:: bash salt -G 'kernel:Linux' sysctl.default_config """ if ( salt.utils.systemd.booted(__context__) and salt.utils.systemd.version(__context__) >= 207 ): return "/etc/sysctl.d/99-salt.conf" return "/etc/sysctl.conf" def show(config_file=False): """ Return a list of sysctl parameters for this minion config: Pull the data from the system configuration file instead of the live data. CLI Example: .. code-block:: bash salt '*' sysctl.show """ ret = {} if config_file: # If the file doesn't exist, return an empty list if not os.path.exists(config_file): return [] try: with salt.utils.files.fopen(config_file) as fp_: for line in fp_: line = salt.utils.stringutils.to_str(line) if not line.startswith("#") and "=" in line: # search if we have some '=' instead of ' = ' separators SPLIT = " = " if SPLIT not in line: SPLIT = SPLIT.strip() key, value = line.split(SPLIT, 1) key = key.strip() value = value.lstrip() ret[key] = value except OSError: log.error("Could not open sysctl file") return None else: cmd = "sysctl -a" out = __salt__["cmd.run_stdout"](cmd, output_loglevel="trace") for line in out.splitlines(): if not line or " = " not in line: continue comps = line.split(" = ", 1) ret[comps[0]] = comps[1] return ret def get(name): """ Return a single sysctl parameter for this minion CLI Example: .. code-block:: bash salt '*' sysctl.get net.ipv4.ip_forward """ cmd = "sysctl -n {}".format(name) out = __salt__["cmd.run"](cmd, python_shell=False) return out def assign(name, value): """ Assign a single sysctl parameter for this minion CLI Example: .. code-block:: bash salt '*' sysctl.assign net.ipv4.ip_forward 1 """ value = str(value) tran_tab = name.translate("".maketrans("./", "/.")) sysctl_file = "/proc/sys/{}".format(tran_tab) if not os.path.exists(sysctl_file): raise CommandExecutionError("sysctl {} does not exist".format(name)) ret = {} cmd = 'sysctl -w {}="{}"'.format(name, value) data = __salt__["cmd.run_all"](cmd, python_shell=False) out = data["stdout"] err = data["stderr"] # Example: # # sysctl -w net.ipv4.tcp_rmem="4096 87380 16777216" # net.ipv4.tcp_rmem = 4096 87380 16777216 regex = re.compile(r"^{}\s+=\s+{}$".format(re.escape(name), re.escape(value))) if not regex.match(out) or "Invalid argument" in str(err): if data["retcode"] != 0 and err: error = err else: error = out raise CommandExecutionError("sysctl -w failed: {}".format(error)) new_name, new_value = out.split(" = ", 1) ret[new_name] = new_value return ret def persist(name, value, config=None): """ Assign and persist a simple sysctl parameter for this minion. If ``config`` is not specified, a sensible default will be chosen using :mod:`sysctl.default_config <salt.modules.linux_sysctl.default_config>`. CLI Example: .. code-block:: bash salt '*' sysctl.persist net.ipv4.ip_forward 1 """ if config is None: config = default_config() edited = False # If the sysctl.conf is not present, add it if not os.path.isfile(config): sysctl_dir = os.path.dirname(config) if not os.path.exists(sysctl_dir): os.makedirs(sysctl_dir) try: with salt.utils.files.fopen(config, "w+") as _fh: _fh.write("#\n# Kernel sysctl configuration\n#\n") except OSError: msg = "Could not write to file: {0}" raise CommandExecutionError(msg.format(config)) # Read the existing sysctl.conf nlines = [] try: with salt.utils.files.fopen(config, "r") as _fh: # Use readlines because this should be a small file # and it seems unnecessary to indent the below for # loop since it is a fairly large block of code. config_data = salt.utils.data.decode(_fh.readlines()) except OSError: msg = "Could not read from file: {0}" raise CommandExecutionError(msg.format(config)) for line in config_data: if line.startswith("#"): nlines.append(line) continue if "=" not in line: nlines.append(line) continue # Strip trailing whitespace and split the k,v comps = [i.strip() for i in line.split("=", 1)] # On Linux procfs, files such as /proc/sys/net/ipv4/tcp_rmem or any # other sysctl with whitespace in it consistently uses 1 tab. Lets # allow our users to put a space or tab between multi-value sysctls # and have salt not try to set it every single time. if isinstance(comps[1], str) and " " in comps[1]: comps[1] = re.sub(r"\s+", "\t", comps[1]) # Do the same thing for the value 'just in case' if isinstance(value, str) and " " in value: value = re.sub(r"\s+", "\t", value) if len(comps) < 2: nlines.append(line) continue if name == comps[0]: # This is the line to edit if str(comps[1]) == str(value): # It is correct in the config, check if it is correct in /proc if str(get(name)) != str(value): assign(name, value) return "Updated" else: return "Already set" nlines.append("{} = {}\n".format(name, value)) edited = True continue else: nlines.append(line) if not edited: nlines.append("{} = {}\n".format(name, value)) try: with salt.utils.files.fopen(config, "wb") as _fh: _fh.writelines(salt.utils.data.encode(nlines)) except OSError: msg = "Could not write to file: {0}" raise CommandExecutionError(msg.format(config)) assign(name, value) return "Updated"

Save