attachmentsystem overhaul and cid replacement

CHANGELOG.md

@@ -1,5 +1,13 @@
 # Changelog
 
+## Nov 19th 2023 - V1.1.3
+- Switched SMTP server to Python3 and aiosmptd
+- Switched PHP backend to PHP8.1
+- Implemented content-id replacement with smart link to API so embedded images will now work
+- Updated JSON to include details about attachments (filename,size in bytes,id,cid and a download URL)
+- Removed quotes from ini settings
+- Made docker start script more neat
+
 ## Nov 13th 2023 - V1.0.0
 - Launch of V1.0.0
 - Complete rewrite of the GUI

README.md

@@ -84,7 +84,7 @@ In Docker you can use the following environment variables:
   - [x] Storing received mails in JSON
   - [x] Storing file attachments
 - [x] Docker files and configs
-- [ ] Web interface
+- [x] Web interface
   - [x] Choose email
   - [x] Get random email address
   - [x] Download attachments safely
@@ -96,7 +96,7 @@ In Docker you can use the following environment variables:
   - [x] Delete messages
   - [x] Make better theme
   - [x] Secure HTML, so no malicious things can be loaded
-  - [ ] Display embedded images inline using Content-ID
+  - [x] Display embedded images inline using Content-ID
 - [ ] Configurable settings
   - [x] Choose domains for random generation
   - [x] Choose if out-of-scope emails are discarded

docker/rootfs/start.sh

@@ -29,7 +29,7 @@ echo ' [+] Setting up config.ini'
 _buildConfig() {
     echo "[GENERAL]"
     echo "DOMAINS=${DOMAINS:-localhost}"
-    echo "URL='${URL:-http://localhost:8080}'"
+    echo "URL=${URL:-http://localhost:8080}"
     echo "SHOW_ACCOUNT_LIST=${SHOW_ACCOUNT_LIST:-false}"
     echo "ADMIN=${ADMIN:-}"
     echo "SHOW_LOGS=${SHOW_LOGS:-false}"
@@ -39,7 +39,7 @@ _buildConfig() {
     echo "DISCARD_UNKNOWN=${DISCARD_UNKNOWN:-true}"
 
     echo "[DATETIME]"
-    echo "DATEFORMAT='${DATEFORMAT:-D.M.YYYY HH:mm}'"
+    echo "DATEFORMAT=${DATEFORMAT:-D.M.YYYY HH:mm}"
 
     echo "[CLEANUP]"
     echo "DELETE_OLDER_THAN_DAYS=${DELETE_OLDER_THAN_DAYS:-false}"

python/mailserver3.py

@@ -19,6 +19,7 @@
 DELETE_OLDER_THAN_DAYS = False
 DOMAINS = []
 LAST_CLEANUP = 0
+URL = ""
 
 class CustomHandler:
     async def handle_DATA(self, server, session, envelope):
@@ -31,6 +32,8 @@ async def handle_DATA(self, server, session, envelope):
         logger.debug('Message addressed from: %s' % envelope.mail_from)
         logger.debug('Message addressed to: %s' % str(rcpts))
 
+        filenamebase = str(int(round(time.time() * 1000)))
+
         # Get the raw email data
         raw_email = envelope.content.decode('utf-8')
 
@@ -50,25 +53,11 @@ async def handle_DATA(self, server, session, envelope):
                 html += part.get_payload()
             else:
                 filename = part.get_filename()
+                cid = part.get('Content-ID')
+                logger.debug('Handling attachment: "%s" of type "%s" with CID "%s"',filename, part.get_content_type(), cid)
                 if filename is None:
                     filename = 'untitled'
-                attachments['file%d' % len(attachments)] = (filename,part.get_payload(decode=True))
-
-        edata = {
-                'subject': message['subject'],
-                'body': plaintext,
-                'htmlbody': html,
-                'from': message['from'],
-                'attachments':[]
-            }
-        savedata = {'sender_ip':peer[0],
-                    'from':message['from'],
-                    'rcpts':rcpts,
-                    'raw':raw_email,
-                    'parsed':edata
-                    }
-
-        filenamebase = str(int(round(time.time() * 1000)))
+                attachments['file%d' % len(attachments)] = (filename,part.get_payload(decode=True),cid)
 
         for em in rcpts:
                 em = em.lower()
@@ -89,6 +78,22 @@ async def handle_DATA(self, server, session, envelope):
 
                 if not os.path.exists("../data/"+em):
                     os.mkdir( "../data/"+em, 0o755 )
+
+
+                edata = {
+                    'subject': message['subject'],
+                    'body': plaintext,
+                    'htmlbody': self.replace_cid_with_attachment_id(html, attachments,filenamebase,em),
+                    'from': message['from'],
+                    'attachments':[],
+                    'attachments_details':[]
+                }
+                savedata = {'sender_ip':peer[0],
+                    'from':message['from'],
+                    'rcpts':rcpts,
+                    'raw':raw_email,
+                    'parsed':edata
+                }
 
                 #same attachments if any
                 for att in attachments:
@@ -99,12 +104,32 @@ async def handle_DATA(self, server, session, envelope):
                     file.write(attd[1])
                     file.close()
                     edata["attachments"].append(filenamebase+"-"+attd[0])
+                    edata["attachments_details"].append({
+                            "filename":attd[0],
+                            "cid":attd[2][1:-1],
+                            "id":filenamebase+"-"+attd[0],
+                            "download_url":URL+"/api/attachment/"+em+"/"+filenamebase+"-"+attd[0],
+                            "size":len(attd[1])
+                        })
 
                 # save actual json data
                 with open("../data/"+em+"/"+filenamebase+".json", "w") as outfile:
                     json.dump(savedata, outfile)
 
         return '250 OK'
+
+    def replace_cid_with_attachment_id(self, html_content, attachments,filenamebase,email):
+        # Replace cid references with attachment filename
+        for attachment_id in attachments:
+            attachment = attachments[attachment_id]
+            filename = attachment[0]
+            cid = attachment[2]
+            if cid is None:
+                continue
+            cid = cid[1:-1]
+            if cid is not None:
+                html_content = html_content.replace('cid:' + cid, "/api/attachment/"+email+"/"+filenamebase+"-"+filename)
+        return html_content
 
 def cleanup():
     if(DELETE_OLDER_THAN_DAYS == False or time.time() - LAST_CLEANUP < 86400):
@@ -150,6 +175,7 @@ async def run(port):
         if("discard_unknown" in Config.options("MAILSERVER")):
             DISCARD_UNKNOWN = (Config.get("MAILSERVER", "DISCARD_UNKNOWN").lower() == "true")
         DOMAINS = Config.get("GENERAL", "DOMAINS").lower().split(",")
+        URL = Config.get("GENERAL", "URL")
 
         if("CLEANUP" in Config.sections() and "delete_older_than_days" in Config.options("CLEANUP")):
             DELETE_OLDER_THAN_DAYS = (Config.get("CLEANUP", "DELETE_OLDER_THAN_DAYS").lower() == "true")

tools/testmail.txt

@@ -21,17 +21,21 @@ Content-Type: text/html
 
 <html>
   <body>
+    <p><img src="cid:part1.wUxVdgTp.JyT3JNov@localhost.dev"
+        moz-do-not-send="false"></p>
+    <p><br>
     <p>This is the HTML part of the email.</p>
   </body>
 </html>
 
 --alternative-boundary--
 
 --boundary-string
-Content-Type: application/octet-stream
-Content-Disposition: attachment; filename="example.txt"
+Content-Type: image/svg+xml
+Content-Id: <part1.wUxVdgTp.JyT3JNov@localhost.dev>
+Content-Disposition: attachment; filename="42.svg"
 
-(Attach the contents of your file here)
+<svg role="img" viewBox="0 0 24 24" xmlns="http://www.w3.org/2000/svg"><title>42</title><path d="M24 12.42l-4.428 4.415H24zm-4.428-4.417l-4.414 4.418v4.414h4.414V12.42L24 8.003V3.575h-4.428zm-4.414 0l4.414-4.428h-4.414zM0 15.996h8.842v4.43h4.412V12.42H4.428l8.826-8.846H8.842L0 12.421z"/></svg>
 
 --boundary-string--
 .