attachment handling with magic and sub-URI parsing

app/Entities.py

@@ -97,6 +97,7 @@ class QuarMail:
   msg_size = None
   href = None
   attach_count = None
+  uri_count = None
 
   def __init__(self,qm_ref):
     if 'id' not in qm_ref:
@@ -139,6 +140,8 @@ class QuarMail:
       self.href = qm_ref['href']
     if 'attach_count' in qm_ref:
       self.attach_count = qm_ref['attach_count']
+    if 'uri_count' in qm_ref:
+      self.uri_count = qm_ref['uri_count']
 
 class AttachmentException(Exception):
   message = None
@@ -150,6 +153,7 @@ class Attachment:
   filename = None
   content_type = None
   content_encoding = None
+  magic = None
   comment = None
   mailbox_id = None
   imap_uid = None
@@ -167,6 +171,9 @@ class Attachment:
     self.content_type = at_ref['content_type']
     if 'content_encoding' in at_ref:
       self.content_encoding = at_ref['content_encoding']
+    if 'magic' not in at_ref:
+      raise AttachmentException("'magic' is mandatory!")
+    self.magic = at_ref['magic']
     if 'comment' in at_ref:
       self.comment = at_ref['comment']
     if 'mailbox_id' not in at_ref:

app/Gulag.py

@@ -1,4 +1,4 @@
-import json,sys,os,logging,re
+import json,sys,os,logging,re,magic
 import email,email.header,email.message
 from GulagDB import GulagDB,GulagDBException
 from GulagMailbox import IMAPmailbox,IMAPmailboxException
@@ -30,6 +30,7 @@ class Gulag:
       raise GulagException(whoami(self) + "Logging not configured!")
     if('filename' in self.config['logging'] and 
        len(self.config['logging']['filename']) > 0):
+      # TODO: Exception handling
       logging.basicConfig(
         filename=self.config['logging']['filename'],
         format='%(asctime)s %(levelname)s %(message)s',
@@ -148,10 +149,16 @@ class Gulag:
             else:
               # filename isn´t encoded
               filename = filename[0][0]
+            attach_magic = None
+            try:
+              attach_magic = magic.from_buffer(part.get_payload(decode=True))
+            except:
+              logging.info(whoami(self) + ": " + str(sys.exc_info()))
             attach_id = self.db.add_attachment({
               'filename': filename,
               'content_type': part.get_content_type(),
-              'content_encoding': part['Content-Transfer-Encoding']
+              'content_encoding': part['Content-Transfer-Encoding'],
+              'magic': attach_magic
             })
             attachments.append(attach_id)
           # End if part.get_filename()
@@ -168,6 +175,9 @@ class Gulag:
           for quarmail_id in quarmail_ids:
             for attachment_id in attachments:
               self.db.quarmail2attachment(str(quarmail_id), str(attachment_id))
+              logging.info(whoami(self) + 
+                "Attachment("+str(attachment_id)+")@QuarMail("+str(quarmail_id)+") imported"
+              )
         # link message with uris
         if(len(uris) > 0):
           for quarmail_id in quarmail_ids:
@@ -178,6 +188,9 @@ class Gulag:
                   "fqdn": extract_fqdn(uri)
                 })
                 self.db.quarmail2uri(str(quarmail_id), str(uri_id))
+                logging.info(whoami(self) + 
+                  "URI("+str(uri_id)+")@QuarMail("+str(quarmail_id)+") imported"
+                )
               except GulagDBException as e:
                 logging.error(whoami(self) + e.message)
       # End for(unseen)

app/GulagDB.py

@@ -185,7 +185,9 @@ class GulagDB:
     try: 
       cursor = self.conn.cursor()
       query = "select *,(select count(*) from QuarMail2Attachment"
-      query += " where QuarMails.id=QuarMail2Attachment.quarmail_id) as attach_count"
+      query += " where QuarMails.id=QuarMail2Attachment.quarmail_id) as attach_count,"
+      query += " (select count(*) from QuarMail2URI"
+      query += " where QuarMails.id=QuarMail2URI.quarmail_id) as uri_count"
       query += " from QuarMails " + self.get_where_clause(args)
       query += " " + self.get_limit_clause(args) + " ;"
       cursor.execute(query)
@@ -213,10 +215,10 @@ class GulagDB:
   def get_quarmail(self,args):
     try:
       cursor = self.conn.cursor()
-      # TODO: build SQL query by args
-      #query = "select * from QuarMails where id='" + args['id'] + "';"
       query = "select *,(select count(*) from QuarMail2Attachment"
-      query += " where QuarMails.id=QuarMail2Attachment.quarmail_id) as attach_count"
+      query += " where QuarMails.id=QuarMail2Attachment.quarmail_id) as attach_count,"
+      query += " (select count(*) from QuarMail2URI"
+      query += " where QuarMails.id=QuarMail2URI.quarmail_id) as uri_count"
       query += " from QuarMails where QuarMails.id="+ str(args['id']) +";"
       cursor.execute(query)
       data = cursor.fetchall()
@@ -266,8 +268,9 @@ class GulagDB:
     try:
       cursor = self.conn.cursor()
       cursor.execute("insert into Attachments " +
-        "(filename, content_type, content_encoding) values (%s,%s,%s)",
-        (attach['filename'], attach['content_type'], attach['content_encoding'])
+        "(filename,content_type,content_encoding,magic) values (%s,%s,%s,%s)",
+        (attach['filename'],attach['content_type'],
+         attach['content_encoding'],attach['magic'])
       )
       return cursor.lastrowid
     except mariadb.Error as e:

app/GulagUtils.py

@@ -1,4 +1,5 @@
-import sys,re
+import sys,re,urllib
+from urllib.parse import urlparse
 from smtplib import SMTP
 
 def whoami(obj):
@@ -6,7 +7,7 @@ def whoami(obj):
 
 def send_mail(args):
   try:
-  # FIXME: SMTP tranaport security and authentication!
+  # FIXME: SMTP transport security and authentication!
   # with SMTP(host=mailbox['smtp_server'],port=mailbox['smtp_port']) as smtp:
   #   try:
   #     smtp.sendmail(
@@ -20,17 +21,22 @@ def send_mail(args):
   except TimeoutError as e:
     raise Exception('xyz') from e
 
-def extract_uris(string):
+def extract_uris(input_text):
   uris = {}
   uri_pattern = r'(https?:\/\/[^\s<>"]+)'
-  for m in re.finditer(uri_pattern, string):
-    uris[m.group(0)] = {}
+  for m in re.finditer(uri_pattern, input_text):
+    uri = urllib.parse.unquote(m.group(0))
+    uris[uri] = {}
+    # extract sub-URIs (google redirector: https://www.google.de/url?sa=t&url=...)
+    for m2 in re.finditer(uri_pattern, uri):
+      suburi = urllib.parse.unquote(m2.group(0))
+      uris[suburi] = {"suburi": True}
   return uris
 
 def extract_fqdn(uri):
-  uri_pattern = r'(https?:\/\/[^\s<>"]+)'
-  if(re.match(uri_pattern,uri)):
-    m = re.match(r'https?:\/\/([^:\/]+)', uri)
-    return m.group(1)
-  else:
+  puri = None
+  try:
+    puri = urlparse(uri)
+    return puri.hostname
+  except ValueError as e:
     return None

db/gulag.sql

@@ -46,6 +46,7 @@ create table Attachments (
   filename varchar(256) not null,
   content_type varchar(256) not null,
   content_encoding varchar(64),
+  magic varchar(128),
   comment varchar(256)
 )ENGINE = InnoDB;
 

docker/gulag-server/debian/Dockerfile

@@ -5,11 +5,13 @@ ENV DEBIAN_FRONTEND=noninteractive \
  TZ=Europe/Berlin
 
 RUN set -ex ; \
-      apt-get -qq update \
-    && apt-get -qq --no-install-recommends install \
-       uwsgi-plugin-python3 python3-setuptools python3-flask \
-       python3-flask-restful python3-mysql.connector \
-       uwsgi uwsgi-plugin-python3 procps net-tools
+    apt-get -qq update \
+ && apt-get -qq --no-install-recommends install \
+      uwsgi-plugin-python3 python3-setuptools python3-flask \
+      python3-flask-restful python3-mysql.connector \
+      uwsgi uwsgi-plugin-python3 procps net-tools \
+      python3-pip libmagic1 \
+ && pip3 install python-magic
 
 RUN /bin/mkdir /config /socket /app
 COPY app/*.py /app/

gulag-openapi-2.0.yaml

@@ -307,6 +307,9 @@ definitions:
       attach_count:
         type: integer
         description: number of attachments
+      uri_count:
+        type: integer
+        description: number of uris
       rfc822_message:
         type: string
         description: full RFC822 email message
@@ -317,6 +320,7 @@ definitions:
     - filename
     - content_encoding
     - content_type
+    - magic
     - mailbox_id
     - imap_uid
     - href
@@ -336,6 +340,9 @@ definitions:
       content_type:
         type: string
         example: image/jpeg
+      magic:
+        type: string
+        example: "PDF document, version 1.2"
       href:
         type: string
         description: hypermedia