#!/usr/bin/python # Provides a somewhat random, somewhat compat, somewhat useful mock version of # http://docs.amazonwebservices.com # /AWSEC2/2007-08-29/DeveloperGuide/AESDG-chapter-instancedata.htm """ To use this to mimic the EC2 metadata service entirely, run it like: # Where 'eth0' is *some* interface. sudo ifconfig eth0:0 169.254.169.254 netmask 255.255.255.255 sudo ./mock-meta.py -a 169.254.169.254 -p 80 Then: wget -q http://169.254.169.254/latest/meta-data/instance-id -O -; echo curl --silent http://169.254.169.254/latest/meta-data/instance-id ; echo ec2metadata --instance-id """ import argparse import functools import json import logging import os import random import socket import string import sys import yaml try: from BaseHTTPServer import HTTPServer, BaseHTTPRequestHandler import httplib as hclient except ImportError: from http.server import HTTPServer, BaseHTTPRequestHandler from http import client as hclient log = logging.getLogger('meta-server') EC2_VERSIONS = [ '1.0', '2007-01-19', '2007-03-01', '2007-08-29', '2007-10-10', '2007-12-15', '2008-02-01', '2008-09-01', '2009-04-04', ] BLOCK_DEVS = [ 'ami', 'ephemeral0', 'root', ] DEV_PREFIX = 'v' # This seems to vary alot depending on images... DEV_MAPPINGS = { 'ephemeral0': '%sda2' % (DEV_PREFIX), 'root': '/dev/%sda1' % (DEV_PREFIX), 'ami': '%sda1' % (DEV_PREFIX), 'swap': '%sda3' % (DEV_PREFIX), } META_CAPABILITIES = [ 'aki-id', 'ami-id', 'ami-launch-index', 'ami-manifest-path', 'ari-id', 'block-device-mapping/', 'hostname', 'instance-action', 'instance-id', 'instance-type', 'local-hostname', 'local-ipv4', 'placement/', 'product-codes', 'public-hostname', 'public-ipv4', 'public-keys/', 'reservation-id', 'security-groups' ] PUB_KEYS = { 'brickies': [ ('ssh-rsa ' 'AAAAB3NzaC1yc2EAAAABIwAAAQEA3I7VUf2l5gSn5uavROsc5HRDpZdQueUq5ozemN' 'Sj8T7enqKHOEaFoU2VoPgGEWC9RyzSQVeyD6s7APMcE82EtmW4skVEgEGSbDc1pvxz' 'xtchBj78hJP6Cf5TCMFSXw+Fz5rF1dR23QDbN1mkHs7adr8GW4kSWqU7Q7NDwfIrJJ' 'tO7Hi42GyXtvEONHbiRPOe8stqUly7MvUoN+5kfjBM8Qqpfl2+FNhTYWpMfYdPUnE7' 'u536WqzFmsaqJctz3gBxH9Ex7dFtrxR4qiqEr9Qtlu3xGn7Bw07/+i1D+ey3ONkZLN' '+LQ714cgj8fRS4Hj29SCmXp5Kt5/82cD/VN3NtHw== brickies'), '', ], } INSTANCE_TYPES = [ 'm1.large', 'm1.medium', 'm1.small', 'm1.xlarge', ] AVAILABILITY_ZONES = [ "us-east-1a", "us-east-1b", "us-east-1c", "us-east-1d", 'eu-west-1a', 'eu-west-1b', 'us-west-1', ] PLACEMENT_CAPABILITIES = { 'availability-zone': AVAILABILITY_ZONES, } NOT_IMPL_RESPONSE = json.dumps({}) class WebException(Exception): def __init__(self, code, msg): Exception.__init__(self, msg) self.code = code def yamlify(data): formatted = yaml.dump(data, line_break="\n", indent=4, explicit_start=True, explicit_end=True, default_flow_style=False) return formatted def format_text(text): if not len(text): return "<<" lines = text.splitlines() nlines = [] for line in lines: nlines.append("<< %s" % line) return "\n".join(nlines) def traverse(keys, mp): result = dict(mp) for k in keys: try: result = result.get(k) except (AttributeError, TypeError): result = None break return result ID_CHARS = [c for c in (string.ascii_uppercase + string.digits)] def id_generator(size=6, lower=False): txt = ''.join(random.choice(ID_CHARS) for x in range(size)) if lower: return txt.lower() else: return txt def get_ssh_keys(): keys = {} keys.update(PUB_KEYS) # Nice helper to add in the 'running' users key (if they have one) key_pth = os.path.expanduser('~/.ssh/id_rsa.pub') if not os.path.isfile(key_pth): key_pth = os.path.expanduser('~/.ssh/id_dsa.pub') if os.path.isfile(key_pth): with open(key_pth, 'rb') as fh: contents = fh.read() keys[os.getlogin()] = [contents, ''] return keys class HTTPServerV6(HTTPServer): address_family = socket.AF_INET6 class MetaDataHandler(object): def __init__(self, opts): self.opts = opts self.instances = {} def get_data(self, params, who, **kwargs): if not params: # Show the root level capabilities when # no params are passed... caps = sorted(META_CAPABILITIES) return "\n".join(caps) action = params[0] action = action.lower() if action == 'instance-id': return 'i-%s' % (id_generator(lower=True)) elif action == 'ami-launch-index': return "%s" % random.choice([0, 1, 2, 3]) elif action == 'aki-id': return 'aki-%s' % (id_generator(lower=True)) elif action == 'ami-id': return 'ami-%s' % (id_generator(lower=True)) elif action == 'ari-id': return 'ari-%s' % (id_generator(lower=True)) elif action == 'block-device-mapping': nparams = params[1:] if not nparams: return "\n".join(BLOCK_DEVS) else: subvalue = traverse(nparams, DEV_MAPPINGS) if not subvalue: return "\n".join(sorted(list(DEV_MAPPINGS.keys()))) else: return str(subvalue) elif action in ['hostname', 'local-hostname', 'public-hostname']: # Just echo back there own hostname that they called in on.. return "%s" % (who) elif action == 'instance-type': return random.choice(INSTANCE_TYPES) elif action == 'ami-manifest-path': return 'my-amis/spamd-image.manifest.xml' elif action == 'security-groups': return 'default' elif action in ['local-ipv4', 'public-ipv4']: # Just echo back there own ip that they called in on... return "%s" % (kwargs.get('client_ip', '10.0.0.1')) elif action == 'reservation-id': return "r-%s" % (id_generator(lower=True)) elif action == 'product-codes': return "%s" % (id_generator(size=8)) elif action == 'public-keys': nparams = params[1:] # This is a weird kludge, why amazon why!!! # public-keys is messed up, list of /latest/meta-data/public-keys/ # shows something like: '0=brickies' # but a GET to /latest/meta-data/public-keys/0=brickies will fail # you have to know to get '/latest/meta-data/public-keys/0', then # from there you get a 'openssh-key', which you can get. # this hunk of code just re-works the object for that. avail_keys = get_ssh_keys() key_ids = sorted(list(avail_keys.keys())) if nparams: mybe_key = nparams[0] try: key_id = int(mybe_key) key_name = key_ids[key_id] except ValueError: raise WebException(hclient.BAD_REQUEST, "%s: not an integer" % mybe_key) except IndexError: raise WebException(hclient.NOT_FOUND, "Unknown key id %r" % mybe_key) # Extract the possible sub-params result = traverse(nparams[1:], { "openssh-key": "\n".join(avail_keys[key_name]), }) if isinstance(result, (dict)): # TODO(harlowja): This might not be right?? result = "\n".join(sorted(result.keys())) if not result: result = '' return result else: contents = [] for (i, key_id) in enumerate(key_ids): contents.append("%s=%s" % (i, key_id)) return "\n".join(contents) elif action == 'placement': nparams = params[1:] if not nparams: pcaps = sorted(PLACEMENT_CAPABILITIES.keys()) return "\n".join(pcaps) else: pentry = nparams[0].strip().lower() if pentry == 'availability-zone': zones = PLACEMENT_CAPABILITIES[pentry] return "%s" % random.choice(zones) else: return "%s" % (PLACEMENT_CAPABILITIES.get(pentry, '')) else: log.warning(("Did not implement action %s, " "returning empty response: %r"), action, NOT_IMPL_RESPONSE) return NOT_IMPL_RESPONSE class UserDataHandler(object): def __init__(self, opts): self.opts = opts def _get_user_blob(self, **kwargs): blob = None if self.opts['user_data_file'] is not None: blob = self.opts['user_data_file'] if not blob: blob_mp = { 'hostname': kwargs.get('who', 'localhost'), } lines = [ "#cloud-config", yamlify(blob_mp), ] blob = "\n".join(lines) return blob.strip() def get_data(self, params, who, **kwargs): if not params: return self._get_user_blob(who=who) return NOT_IMPL_RESPONSE # Seem to need to use globals since can't pass # data into the request handlers instances... # Puke! meta_fetcher = None user_fetcher = None class Ec2Handler(BaseHTTPRequestHandler): def _get_versions(self): versions = ['latest'] + EC2_VERSIONS versions = sorted(versions) return "\n".join(versions) def log_message(self, fmt, *args): msg = "%s - %s" % (self.address_string(), fmt % (args)) log.info(msg) def _find_method(self, path): # Puke! (globals) func_mapping = { 'user-data': user_fetcher.get_data, 'meta-data': meta_fetcher.get_data, } segments = [piece for piece in path.split('/') if len(piece)] log.info("Received segments %s", segments) if not segments: return self._get_versions date = segments[0].strip().lower() if date not in self._get_versions(): raise WebException(hclient.BAD_REQUEST, "Unknown version format %r" % date) if len(segments) < 2: raise WebException(hclient.BAD_REQUEST, "No action provided") look_name = segments[1].lower() if look_name not in func_mapping: raise WebException(hclient.BAD_REQUEST, "Unknown requested data %r" % look_name) base_func = func_mapping[look_name] who = self.address_string() ip_from = self.client_address[0] if who == ip_from: # Nothing resolved, so just use 'localhost' who = 'localhost' kwargs = { 'params': list(segments[2:]), 'who': who, 'client_ip': ip_from, } return functools.partial(base_func, **kwargs) def _do_response(self): who = self.client_address log.info("Got a call from %s for path %s", who, self.path) try: func = self._find_method(self.path) data = func() if not data: data = '' self.send_response(hclient.OK) self.send_header("Content-Type", "binary/octet-stream") self.send_header("Content-Length", len(data)) log.info("Sending data (len=%s):\n%s", len(data), format_text(data)) self.end_headers() self.wfile.write(data.encode()) except RuntimeError as e: log.exception("Error somewhere in the server.") self.send_error(hclient.INTERNAL_SERVER_ERROR, message=str(e)) except WebException as e: code = e.code log.exception(str(e)) self.send_error(code, message=str(e)) def do_GET(self): self._do_response() def do_POST(self): self._do_response() def setup_logging(log_level, fmt='%(levelname)s: @%(name)s : %(message)s'): root_logger = logging.getLogger() console_logger = logging.StreamHandler(sys.stdout) console_logger.setFormatter(logging.Formatter(fmt)) root_logger.addHandler(console_logger) root_logger.setLevel(log_level) def extract_opts(): parser = argparse.ArgumentParser() parser.add_argument("-p", "--port", dest="port", action="store", type=int, default=80, metavar="PORT", help=("port from which to serve traffic" " (default: %default)")) parser.add_argument("-a", "--addr", dest="address", action="store", type=str, default='::', metavar="ADDRESS", help=("address from which to serve traffic" " (default: %default)")) parser.add_argument("-f", '--user-data-file', dest='user_data_file', action='store', metavar='FILE', help=("user data filename to serve back to" "incoming requests")) parser.add_argument('extra', nargs='*') args = parser.parse_args() out = {'port': args.port, 'address': args.address, 'extra': args.extra, 'user_data_file': None} if args.user_data_file: if not os.path.isfile(args.user_data_file): parser.error("Option -f specified a non-existent file") with open(args.user_data_file, 'rb') as fh: out['user_data_file'] = fh.read() return out def setup_fetchers(opts): global meta_fetcher global user_fetcher meta_fetcher = MetaDataHandler(opts) user_fetcher = UserDataHandler(opts) def run_server(): # Using global here since it doesn't seem like we # can pass opts into a request handler constructor... opts = extract_opts() setup_logging(logging.DEBUG) setup_fetchers(opts) log.info("CLI opts: %s", opts) server_address = (opts['address'], opts['port']) server = HTTPServerV6(server_address, Ec2Handler) sa = server.socket.getsockname() log.info("Serving ec2 metadata on %s using port %s ...", sa[0], sa[1]) server.serve_forever() if __name__ == '__main__': run_server() # vi: ts=4 expandtab