Merge pull request #66 from edgd1er/dev

client: add -D to discover KMS server #51

docker/docker-py3-kms-minimal/Dockerfile

@@ -28,7 +28,7 @@ RUN apk add --no-cache --update \
   shadow \
   netcat-openbsd \
   build-base python3-dev \
-  && pip3 install --no-cache peewee tzlocal pytz wheel \
+  && pip3 install --no-cache-dir peewee tzlocal pytz wheel dnspython \
   && apk del git build-base python3-dev \
   && addgroup power_users  \
   && adduser -S py-kms -G users -s /bin/bash \

docker/docker-py3-kms/Dockerfile

@@ -17,7 +17,7 @@ ENV LOGSIZE ""
 ENV TZ America/Chicago
 
 COPY py-kms /home/py-kms/
-#hadolint ignore=DL3013,DL3018
+
 RUN apk add --no-cache --update \
   bash \
   git \
@@ -36,7 +36,7 @@ RUN apk add --no-cache --update \
   && git clone --branch master --depth 1 https://github.com/coleifer/sqlite-web.git /tmp/sqlite_web \
   && mv /tmp/sqlite_web/sqlite_web /home/  \
   && rm -rf /tmp/sqlite_web \
-  && pip3 install --no-cache-dir peewee tzlocal pytz pysqlite3 wheel \
+  && pip3 install --no-cache-dir peewee tzlocal pytz pysqlite3 wheel dnspython \
   && apk del git build-base python3-dev \
   && mkdir /db/ \
   && addgroup power_users  \
@@ -52,7 +52,7 @@ COPY docker/start.py /usr/bin/start.py
 RUN chmod 755 /usr/bin/entrypoint.py
 
 WORKDIR /home/py-kms
-#USER py-kms
+
 EXPOSE ${PORT}/tcp
 EXPOSE 8080
 

docs/Usage.md

@@ -143,6 +143,12 @@ user@host ~/path/to/folder/py-kms $ python3 pykms_Server.py -V DEBUG
 user@host ~/path/to/folder/py-kms $ python3 pykms_Client.py -V DEBUG
 ```
 
+If you wish to get KMS server from DNS server: (ie perform a DNS resolution on _vlmcs._tcp.domain.tld, if ever there are several answers, only the first one is selected.). Althought that mode is supposed to be specific to devices connect to an Active Directory domain, setting a fully qualified name and a workgroup may help to use that automatic KMS discovery feature.  
+```
+user@host ~/path/to/folder/py-kms $ python3 pykms_Client.py -V DEBUG -F STDOUT -D contoso.com
+user@host ~/path/to/folder/py-kms $ python3 pykms_Client.py -V DEBUG -F STDOUT -D contoso.com
+```
+
 Or if you want better specify:
 ```
 user@host ~/path/to/folder/py-kms $ python3 pykms_Server.py <YOUR_IPADDRESS> 1688 -V DEBUG

py-kms/pykms_Client.py

@@ -13,6 +13,12 @@ import logging
 import os
 import threading
 
+import dns.message
+import dns.rdataclass
+import dns.rdatatype
+import dns.query
+import dns.resolver
+
 import pykms_RpcBind, pykms_RpcRequest
 from pykms_Filetimes import dt_to_filetime
 from pykms_Dcerpc import MSRPCHeader, MSRPCBindNak, MSRPCRequestHeader, MSRPCRespHeader
@@ -72,6 +78,7 @@ Type \"STDOUT\" to view log info on stdout. Type \"FILESTDOUT\" to combine previ
 Use \"STDOUTOFF\" to disable stdout messages. Use \"FILEOFF\" if you not want to create logfile.',
                       'def' : os.path.join('.', 'pykms_logclient.log'), 'des' : "logfile"},
         'lsize'    : {'help' : 'Use this flag to set a maximum size (in MB) to the output log file. Deactivated by default.', 'def' : 0, 'des': "logsize"},
+        'discovery' : {'help': 'ask the client to perform a _vlmcs._tcp.domain.tld DNS request to set KMS server.', 'def': None , 'des': 'discovery' },
         }
 
 def client_options():
@@ -99,6 +106,8 @@ def client_options():
                                    default = clt_options['lfile']['def'], help = clt_options['lfile']['help'], type = str)
         client_parser.add_argument("-S", "--logsize", dest = clt_options['lsize']['des'], action = "store",
                                    default = clt_options['lsize']['def'], help = clt_options['lsize']['help'], type = float)
+        client_parser.add_argument("-D", "--discovery", dest = clt_options['discovery']['des'], action = "store",
+                                   default = clt_options['discovery']['def'], help = clt_options['discovery']['help'], type = str)
 
         client_parser.add_argument("-h", "--help", action = "help", help = "show this help message and exit")
 
@@ -186,6 +195,21 @@ def client_update():
         raise RuntimeError(f'Client failed to find machine configuration in kms database - make sure it contains an entry for "{clt_config["mode"]}"')
 
 def client_connect():
+
+        if clt_config['discovery'] is not None:
+          loggerclt.info(f'Using Domain: {clt_config["discovery"]}')
+          r= None
+          try:
+            r = dns.resolver.resolve('_vlmcs._tcp.' + clt_config['discovery'], dns.rdatatype.SRV)
+            for a in r:
+              loggerclt.debug(f'answer KMS server: {a.target} , port: {a.port}')
+            clt_config['ip'] = socket.gethostbyname(r[0].target.to_text())
+            clt_config['port'] = r[0].port
+          except (dns.exception.Timeout, dns.resolver.NXDOMAIN) as e:
+                pretty_printer(log_obj = loggerclt.warning,
+                           put_text = "{reverse}{red}{bold}Cannot resolve '%s'. Error: '%s'...{end}" %(clt_config['discovery'],
+                                                                                                             str(e)))
+
         loggerclt.info("Connecting to %s on port %d" % (clt_config['ip'], clt_config['port']))
         try:
                 clt_sock = socket.create_connection((clt_config['ip'], clt_config['port']), timeout = clt_config['timeoutidle'])