# # VM testing base class # # Copyright 2017-2019 Red Hat Inc. # # Authors: # Fam Zheng # Gerd Hoffmann # # This code is licensed under the GPL version 2 or later. See # the COPYING file in the top-level directory. # import os import re import sys import socket import logging import time import datetime sys.path.append(os.path.join(os.path.dirname(__file__), '..', '..', 'python')) from qemu.accel import kvm_available from qemu.machine import QEMUMachine import subprocess import hashlib import argparse import atexit import tempfile import shutil import multiprocessing import traceback import shlex SSH_KEY_FILE = os.path.join(os.path.dirname(__file__), "..", "keys", "id_rsa") SSH_PUB_KEY_FILE = os.path.join(os.path.dirname(__file__), "..", "keys", "id_rsa.pub") # This is the standard configuration. # Any or all of these can be overridden by # passing in a config argument to the VM constructor. DEFAULT_CONFIG = { 'cpu' : "max", 'machine' : 'pc', 'guest_user' : "qemu", 'guest_pass' : "qemupass", 'root_pass' : "qemupass", 'ssh_key_file' : SSH_KEY_FILE, 'ssh_pub_key_file': SSH_PUB_KEY_FILE, 'memory' : "4G", 'extra_args' : [], 'qemu_args' : "", 'dns' : "", 'ssh_port' : 0, 'install_cmds' : "", 'boot_dev_type' : "block", 'ssh_timeout' : 1, } BOOT_DEVICE = { 'block' : "-drive file={},if=none,id=drive0,cache=writeback "\ "-device virtio-blk,drive=drive0,bootindex=0", 'scsi' : "-device virtio-scsi-device,id=scsi "\ "-drive file={},format=raw,if=none,id=hd0 "\ "-device scsi-hd,drive=hd0,bootindex=0", } class BaseVM(object): envvars = [ "https_proxy", "http_proxy", "ftp_proxy", "no_proxy", ] # The script to run in the guest that builds QEMU BUILD_SCRIPT = "" # The guest name, to be overridden by subclasses name = "#base" # The guest architecture, to be overridden by subclasses arch = "#arch" # command to halt the guest, can be overridden by subclasses poweroff = "poweroff" # enable IPv6 networking ipv6 = True # This is the timeout on the wait for console bytes. socket_timeout = 120 # Scale up some timeouts under TCG. # 4 is arbitrary, but greater than 2, # since we found we need to wait more than twice as long. tcg_ssh_timeout_multiplier = 4 def __init__(self, args, config=None): self._guest = None self._genisoimage = args.genisoimage self._build_path = args.build_path self._efi_aarch64 = args.efi_aarch64 # Allow input config to override defaults. self._config = DEFAULT_CONFIG.copy() if config != None: self._config.update(config) self.validate_ssh_keys() self._tmpdir = os.path.realpath(tempfile.mkdtemp(prefix="vm-test-", suffix=".tmp", dir=".")) atexit.register(shutil.rmtree, self._tmpdir) # Copy the key files to a temporary directory. # Also chmod the key file to agree with ssh requirements. self._config['ssh_key'] = \ open(self._config['ssh_key_file']).read().rstrip() self._config['ssh_pub_key'] = \ open(self._config['ssh_pub_key_file']).read().rstrip() self._ssh_tmp_key_file = os.path.join(self._tmpdir, "id_rsa") open(self._ssh_tmp_key_file, "w").write(self._config['ssh_key']) subprocess.check_call(["chmod", "600", self._ssh_tmp_key_file]) self._ssh_tmp_pub_key_file = os.path.join(self._tmpdir, "id_rsa.pub") open(self._ssh_tmp_pub_key_file, "w").write(self._config['ssh_pub_key']) self.debug = args.debug self._console_log_path = None if args.log_console: self._console_log_path = \ os.path.join(os.path.expanduser("~/.cache/qemu-vm"), "{}.install.log".format(self.name)) self._stderr = sys.stderr self._devnull = open(os.devnull, "w") if self.debug: self._stdout = sys.stdout else: self._stdout = self._devnull netdev = "user,id=vnet,hostfwd=:127.0.0.1:{}-:22" self._args = [ \ "-nodefaults", "-m", self._config['memory'], "-cpu", self._config['cpu'], "-netdev", netdev.format(self._config['ssh_port']) + (",ipv6=no" if not self.ipv6 else "") + (",dns=" + self._config['dns'] if self._config['dns'] else ""), "-device", "virtio-net-pci,netdev=vnet", "-vnc", "127.0.0.1:0,to=20"] if args.jobs and args.jobs > 1: self._args += ["-smp", "%d" % args.jobs] if kvm_available(self.arch): self._args += ["-enable-kvm"] else: logging.info("KVM not available, not using -enable-kvm") self._data_args = [] if self._config['qemu_args'] != None: qemu_args = self._config['qemu_args'] qemu_args = qemu_args.replace('\n',' ').replace('\r','') # shlex groups quoted arguments together # we need this to keep the quoted args together for when # the QEMU command is issued later. args = shlex.split(qemu_args) self._config['extra_args'] = [] for arg in args: if arg: # Preserve quotes around arguments. # shlex above takes them out, so add them in. if " " in arg: arg = '"{}"'.format(arg) self._config['extra_args'].append(arg) def validate_ssh_keys(self): """Check to see if the ssh key files exist.""" if 'ssh_key_file' not in self._config or\ not os.path.exists(self._config['ssh_key_file']): raise Exception("ssh key file not found.") if 'ssh_pub_key_file' not in self._config or\ not os.path.exists(self._config['ssh_pub_key_file']): raise Exception("ssh pub key file not found.") def wait_boot(self, wait_string=None): """Wait for the standard string we expect on completion of a normal boot. The user can also choose to override with an alternate string to wait for.""" if wait_string is None: if self.login_prompt is None: raise Exception("self.login_prompt not defined") wait_string = self.login_prompt # Intentionally bump up the default timeout under TCG, # since the console wait below takes longer. timeout = self.socket_timeout if not kvm_available(self.arch): timeout *= 8 self.console_init(timeout=timeout) self.console_wait(wait_string) def _download_with_cache(self, url, sha256sum=None, sha512sum=None): def check_sha256sum(fname): if not sha256sum: return True checksum = subprocess.check_output(["sha256sum", fname]).split()[0] return sha256sum == checksum.decode("utf-8") def check_sha512sum(fname): if not sha512sum: return True checksum = subprocess.check_output(["sha512sum", fname]).split()[0] return sha512sum == checksum.decode("utf-8") cache_dir = os.path.expanduser("~/.cache/qemu-vm/download") if not os.path.exists(cache_dir): os.makedirs(cache_dir) fname = os.path.join(cache_dir, hashlib.sha1(url.encode("utf-8")).hexdigest()) if os.path.exists(fname) and check_sha256sum(fname) and check_sha512sum(fname): return fname logging.debug("Downloading %s to %s...", url, fname) subprocess.check_call(["wget", "-c", url, "-O", fname + ".download"], stdout=self._stdout, stderr=self._stderr) os.rename(fname + ".download", fname) return fname def _ssh_do(self, user, cmd, check): ssh_cmd = ["ssh", "-t", "-o", "StrictHostKeyChecking=no", "-o", "UserKnownHostsFile=" + os.devnull, "-o", "ConnectTimeout={}".format(self._config["ssh_timeout"]), "-p", self.ssh_port, "-i", self._ssh_tmp_key_file] # If not in debug mode, set ssh to quiet mode to # avoid printing the results of commands. if not self.debug: ssh_cmd.append("-q") for var in self.envvars: ssh_cmd += ['-o', "SendEnv=%s" % var ] assert not isinstance(cmd, str) ssh_cmd += ["%s@127.0.0.1" % user] + list(cmd) logging.debug("ssh_cmd: %s", " ".join(ssh_cmd)) r = subprocess.call(ssh_cmd) if check and r != 0: raise Exception("SSH command failed: %s" % cmd) return r def ssh(self, *cmd): return self._ssh_do(self._config["guest_user"], cmd, False) def ssh_root(self, *cmd): return self._ssh_do("root", cmd, False) def ssh_check(self, *cmd): self._ssh_do(self._config["guest_user"], cmd, True) def ssh_root_check(self, *cmd): self._ssh_do("root", cmd, True) def build_image(self, img): raise NotImplementedError def exec_qemu_img(self, *args): cmd = [os.environ.get("QEMU_IMG", "qemu-img")] cmd.extend(list(args)) subprocess.check_call(cmd) def add_source_dir(self, src_dir): name = "data-" + hashlib.sha1(src_dir.encode("utf-8")).hexdigest()[:5] tarfile = os.path.join(self._tmpdir, name + ".tar") logging.debug("Creating archive %s for src_dir dir: %s", tarfile, src_dir) subprocess.check_call(["./scripts/archive-source.sh", tarfile], cwd=src_dir, stdin=self._devnull, stdout=self._stdout, stderr=self._stderr) self._data_args += ["-drive", "file=%s,if=none,id=%s,cache=writeback,format=raw" % \ (tarfile, name), "-device", "virtio-blk,drive=%s,serial=%s,bootindex=1" % (name, name)] def boot(self, img, extra_args=[]): boot_dev = BOOT_DEVICE[self._config['boot_dev_type']] boot_params = boot_dev.format(img) args = self._args + boot_params.split(' ') args += self._data_args + extra_args + self._config['extra_args'] logging.debug("QEMU args: %s", " ".join(args)) qemu_path = get_qemu_path(self.arch, self._build_path) # Since console_log_path is only set when the user provides the # log_console option, we will set drain_console=True so the # console is always drained. guest = QEMUMachine(binary=qemu_path, args=args, console_log=self._console_log_path, drain_console=True) guest.set_machine(self._config['machine']) guest.set_console() try: guest.launch() except: logging.error("Failed to launch QEMU, command line:") logging.error(" ".join([qemu_path] + args)) logging.error("Log:") logging.error(guest.get_log()) logging.error("QEMU version >= 2.10 is required") raise atexit.register(self.shutdown) self._guest = guest # Init console so we can start consuming the chars. self.console_init() usernet_info = guest.qmp("human-monitor-command", command_line="info usernet") self.ssh_port = None for l in usernet_info["return"].splitlines(): fields = l.split() if "TCP[HOST_FORWARD]" in fields and "22" in fields: self.ssh_port = l.split()[3] if not self.ssh_port: raise Exception("Cannot find ssh port from 'info usernet':\n%s" % \ usernet_info) def console_init(self, timeout = None): if timeout == None: timeout = self.socket_timeout vm = self._guest vm.console_socket.settimeout(timeout) self.console_raw_path = os.path.join(vm._temp_dir, vm._name + "-console.raw") self.console_raw_file = open(self.console_raw_path, 'wb') def console_log(self, text): for line in re.split("[\r\n]", text): # filter out terminal escape sequences line = re.sub("\x1b\[[0-9;?]*[a-zA-Z]", "", line) line = re.sub("\x1b\([0-9;?]*[a-zA-Z]", "", line) # replace unprintable chars line = re.sub("\x1b", "", line) line = re.sub("[\x00-\x1f]", ".", line) line = re.sub("[\x80-\xff]", ".", line) if line == "": continue # log console line sys.stderr.write("con recv: %s\n" % line) def console_wait(self, expect, expectalt = None): vm = self._guest output = "" while True: try: chars = vm.console_socket.recv(1) if self.console_raw_file: self.console_raw_file.write(chars) self.console_raw_file.flush() except socket.timeout: sys.stderr.write("console: *** read timeout ***\n") sys.stderr.write("console: waiting for: '%s'\n" % expect) if not expectalt is None: sys.stderr.write("console: waiting for: '%s' (alt)\n" % expectalt) sys.stderr.write("console: line buffer:\n") sys.stderr.write("\n") self.console_log(output.rstrip()) sys.stderr.write("\n") raise output += chars.decode("latin1") if expect in output: break if not expectalt is None and expectalt in output: break if "\r" in output or "\n" in output: lines = re.split("[\r\n]", output) output = lines.pop() if self.debug: self.console_log("\n".join(lines)) if self.debug: self.console_log(output) if not expectalt is None and expectalt in output: return False return True def console_consume(self): vm = self._guest output = "" vm.console_socket.setblocking(0) while True: try: chars = vm.console_socket.recv(1) except: break output += chars.decode("latin1") if "\r" in output or "\n" in output: lines = re.split("[\r\n]", output) output = lines.pop() if self.debug: self.console_log("\n".join(lines)) if self.debug: self.console_log(output) vm.console_socket.setblocking(1) def console_send(self, command): vm = self._guest if self.debug: logline = re.sub("\n", "", command) logline = re.sub("[\x00-\x1f]", ".", logline) sys.stderr.write("con send: %s\n" % logline) for char in list(command): vm.console_socket.send(char.encode("utf-8")) time.sleep(0.01) def console_wait_send(self, wait, command): self.console_wait(wait) self.console_send(command) def console_ssh_init(self, prompt, user, pw): sshkey_cmd = "echo '%s' > .ssh/authorized_keys\n" \ % self._config['ssh_pub_key'].rstrip() self.console_wait_send("login:", "%s\n" % user) self.console_wait_send("Password:", "%s\n" % pw) self.console_wait_send(prompt, "mkdir .ssh\n") self.console_wait_send(prompt, sshkey_cmd) self.console_wait_send(prompt, "chmod 755 .ssh\n") self.console_wait_send(prompt, "chmod 644 .ssh/authorized_keys\n") def console_sshd_config(self, prompt): self.console_wait(prompt) self.console_send("echo 'PermitRootLogin yes' >> /etc/ssh/sshd_config\n") for var in self.envvars: self.console_wait(prompt) self.console_send("echo 'AcceptEnv %s' >> /etc/ssh/sshd_config\n" % var) def print_step(self, text): sys.stderr.write("### %s ...\n" % text) def wait_ssh(self, wait_root=False, seconds=300, cmd="exit 0"): # Allow more time for VM to boot under TCG. if not kvm_available(self.arch): seconds *= self.tcg_ssh_timeout_multiplier starttime = datetime.datetime.now() endtime = starttime + datetime.timedelta(seconds=seconds) cmd_success = False while datetime.datetime.now() < endtime: if wait_root and self.ssh_root(cmd) == 0: cmd_success = True break elif self.ssh(cmd) == 0: cmd_success = True break seconds = (endtime - datetime.datetime.now()).total_seconds() logging.debug("%ds before timeout", seconds) time.sleep(1) if not cmd_success: raise Exception("Timeout while waiting for guest ssh") def shutdown(self): self._guest.shutdown() def wait(self): self._guest.wait() def graceful_shutdown(self): self.ssh_root(self.poweroff) self._guest.wait() def qmp(self, *args, **kwargs): return self._guest.qmp(*args, **kwargs) def gen_cloud_init_iso(self): cidir = self._tmpdir mdata = open(os.path.join(cidir, "meta-data"), "w") name = self.name.replace(".","-") mdata.writelines(["instance-id: {}-vm-0\n".format(name), "local-hostname: {}-guest\n".format(name)]) mdata.close() udata = open(os.path.join(cidir, "user-data"), "w") print("guest user:pw {}:{}".format(self._config['guest_user'], self._config['guest_pass'])) udata.writelines(["#cloud-config\n", "chpasswd:\n", " list: |\n", " root:%s\n" % self._config['root_pass'], " %s:%s\n" % (self._config['guest_user'], self._config['guest_pass']), " expire: False\n", "users:\n", " - name: %s\n" % self._config['guest_user'], " sudo: ALL=(ALL) NOPASSWD:ALL\n", " ssh-authorized-keys:\n", " - %s\n" % self._config['ssh_pub_key'], " - name: root\n", " ssh-authorized-keys:\n", " - %s\n" % self._config['ssh_pub_key'], "locale: en_US.UTF-8\n"]) proxy = os.environ.get("http_proxy") if not proxy is None: udata.writelines(["apt:\n", " proxy: %s" % proxy]) udata.close() subprocess.check_call([self._genisoimage, "-output", "cloud-init.iso", "-volid", "cidata", "-joliet", "-rock", "user-data", "meta-data"], cwd=cidir, stdin=self._devnull, stdout=self._stdout, stderr=self._stdout) return os.path.join(cidir, "cloud-init.iso") def get_qemu_path(arch, build_path=None): """Fetch the path to the qemu binary.""" # If QEMU environment variable set, it takes precedence if "QEMU" in os.environ: qemu_path = os.environ["QEMU"] elif build_path: qemu_path = os.path.join(build_path, arch + "-softmmu") qemu_path = os.path.join(qemu_path, "qemu-system-" + arch) else: # Default is to use system path for qemu. qemu_path = "qemu-system-" + arch return qemu_path def get_qemu_version(qemu_path): """Get the version number from the current QEMU, and return the major number.""" output = subprocess.check_output([qemu_path, '--version']) version_line = output.decode("utf-8") version_num = re.split(' |\(', version_line)[3].split('.')[0] return int(version_num) def parse_config(config, args): """ Parse yaml config and populate our config structure. The yaml config allows the user to override the defaults for VM parameters. In many cases these defaults can be overridden without rebuilding the VM.""" if args.config: config_file = args.config elif 'QEMU_CONFIG' in os.environ: config_file = os.environ['QEMU_CONFIG'] else: return config if not os.path.exists(config_file): raise Exception("config file {} does not exist".format(config_file)) # We gracefully handle importing the yaml module # since it might not be installed. # If we are here it means the user supplied a .yml file, # so if the yaml module is not installed we will exit with error. try: import yaml except ImportError: print("The python3-yaml package is needed "\ "to support config.yaml files") # Instead of raising an exception we exit to avoid # a raft of messy (expected) errors to stdout. exit(1) with open(config_file) as f: yaml_dict = yaml.safe_load(f) if 'qemu-conf' in yaml_dict: config.update(yaml_dict['qemu-conf']) else: raise Exception("config file {} is not valid"\ " missing qemu-conf".format(config_file)) return config def parse_args(vmcls): def get_default_jobs(): if multiprocessing.cpu_count() > 1: if kvm_available(vmcls.arch): return multiprocessing.cpu_count() // 2 elif os.uname().machine == "x86_64" and \ vmcls.arch in ["aarch64", "x86_64", "i386"]: # MTTCG is available on these arches and we can allow # more cores. but only up to a reasonable limit. User # can always override these limits with --jobs. return min(multiprocessing.cpu_count() // 2, 8) else: return 1 parser = argparse.ArgumentParser( formatter_class=argparse.ArgumentDefaultsHelpFormatter, description="Utility for provisioning VMs and running builds", epilog="""Remaining arguments are passed to the command. Exit codes: 0 = success, 1 = command line error, 2 = environment initialization failed, 3 = test command failed""") parser.add_argument("--debug", "-D", action="store_true", help="enable debug output") parser.add_argument("--image", "-i", default="%s.img" % vmcls.name, help="image file name") parser.add_argument("--force", "-f", action="store_true", help="force build image even if image exists") parser.add_argument("--jobs", type=int, default=get_default_jobs(), help="number of virtual CPUs") parser.add_argument("--verbose", "-V", action="store_true", help="Pass V=1 to builds within the guest") parser.add_argument("--build-image", "-b", action="store_true", help="build image") parser.add_argument("--build-qemu", help="build QEMU from source in guest") parser.add_argument("--build-target", help="QEMU build target", default="check") parser.add_argument("--build-path", default=None, help="Path of build directory, "\ "for using build tree QEMU binary. ") parser.add_argument("--interactive", "-I", action="store_true", help="Interactively run command") parser.add_argument("--snapshot", "-s", action="store_true", help="run tests with a snapshot") parser.add_argument("--genisoimage", default="genisoimage", help="iso imaging tool") parser.add_argument("--config", "-c", default=None, help="Provide config yaml for configuration. "\ "See config_example.yaml for example.") parser.add_argument("--efi-aarch64", default="/usr/share/qemu-efi-aarch64/QEMU_EFI.fd", help="Path to efi image for aarch64 VMs.") parser.add_argument("--log-console", action="store_true", help="Log console to file.") parser.add_argument("commands", nargs="*", help="""Remaining commands after -- are passed to command inside the VM""") return parser.parse_args() def main(vmcls, config=None): try: if config == None: config = DEFAULT_CONFIG args = parse_args(vmcls) if not args.commands and not args.build_qemu and not args.build_image: print("Nothing to do?") return 1 config = parse_config(config, args) logging.basicConfig(level=(logging.DEBUG if args.debug else logging.WARN)) vm = vmcls(args, config=config) if args.build_image: if os.path.exists(args.image) and not args.force: sys.stderr.writelines(["Image file exists: %s\n" % args.image, "Use --force option to overwrite\n"]) return 1 return vm.build_image(args.image) if args.build_qemu: vm.add_source_dir(args.build_qemu) cmd = [vm.BUILD_SCRIPT.format( configure_opts = " ".join(args.commands), jobs=int(args.jobs), target=args.build_target, verbose = "V=1" if args.verbose else "")] else: cmd = args.commands img = args.image if args.snapshot: img += ",snapshot=on" vm.boot(img) vm.wait_ssh() except Exception as e: if isinstance(e, SystemExit) and e.code == 0: return 0 sys.stderr.write("Failed to prepare guest environment\n") traceback.print_exc() return 2 exitcode = 0 if vm.ssh(*cmd) != 0: exitcode = 3 if args.interactive: vm.ssh() if not args.snapshot: vm.graceful_shutdown() return exitcode