├── sample.png
├── .gitattributes
├── docker-compose.yml
├── requirements.txt
├── Dockerfile
├── README.md
├── api.py
└── LICENSE


/sample.png:
--------------------------------------------------------------------------------
https://raw.githubusercontent.com/xme/emlrender/HEAD/sample.png


--------------------------------------------------------------------------------
/.gitattributes:
--------------------------------------------------------------------------------
1 | # Auto detect text files and perform LF normalization
2 | * text=auto
3 | 


--------------------------------------------------------------------------------
/docker-compose.yml:
--------------------------------------------------------------------------------
 1 | version: "2"
 2 | 
 3 | services:
 4 |   emlrender:
 5 |     build: .
 6 |     image: emlrender
 7 |     restart: always
 8 |     hostname: emlrender
 9 |     container_name: emlrender
10 |     ports:
11 |       - '443:443'
12 |     network_mode: bridge
13 | 


--------------------------------------------------------------------------------
/requirements.txt:
--------------------------------------------------------------------------------
 1 | aniso8601==1.2.0
 2 | appdirs==1.4.0
 3 | click==6.7
 4 | Flask==0.12
 5 | Flask-Jsonpify==1.5.0
 6 | Flask-RESTful==0.3.5
 7 | Flask-SQLAlchemy==2.1
 8 | itsdangerous==0.24
 9 | Jinja2==2.9.5
10 | MarkupSafe==0.23
11 | packaging==16.8
12 | pyparsing==2.1.10
13 | python-dateutil==2.6.0
14 | pytz==2016.10
15 | six==1.10.0
16 | SQLAlchemy==1.1.5
17 | Werkzeug==0.11.15
18 | pyopenssl
19 | passlib
20 | flask_httpauth
21 | 


--------------------------------------------------------------------------------
/Dockerfile:
--------------------------------------------------------------------------------
 1 | #
 2 | # EMLRender Dockerfile
 3 | #
 4 | # Author: Xavier Mertens <xavier@rootshell.be>
 5 | # Copyright: GPLv3 (http://gplv3.fsf.org)
 6 | # Fell free to use the code, but please share the changes you've made
 7 | #
 8 |  
 9 | FROM ubuntu:16.04
10 | MAINTAINER Xavier Mertens <xavier@rootshell.be>
11 | 
12 | USER root
13 | RUN apt-get update && apt-get install -y \
14 |     wget python3-pip \
15 |     xvfb xfonts-100dpi xfonts-75dpi xfonts-scalable xfonts-cyrillic \
16 |     libssl-dev \
17 |     flashplugin-nonfree
18 | 
19 | #
20 | # Install precompiled wkhtmltoimage
21 | #
22 | WORKDIR /opt
23 | RUN wget -O - --quiet https://github.com/wkhtmltopdf/wkhtmltopdf/releases/download/0.12.4/wkhtmltox-0.12.4_linux-generic-amd64.tar.xz | xz -d - | tar xvf -
24 | RUN cp wkhtmltox/bin/wkhtmltoimage /usr/local/bin
25 | 
26 | #
27 | # Install imgkit library
28 | # 
29 | RUN pip3 install imgkit
30 | 
31 | #
32 | # Install PIL library
33 | #
34 | RUN pip3 install pillow
35 | 
36 | #
37 | # Install flask
38 | #
39 | WORKDIR /tmp
40 | COPY requirements.txt .
41 | RUN pip3 install -r /tmp/requirements.txt
42 | RUN rm /tmp/requirements.txt&
43 | 
44 | RUN mkdir /opt/emlrender
45 | WORKDIR /opt/emlrender
46 | COPY api.py .
47 | 
48 | EXPOSE 443
49 | 
50 | ENTRYPOINT [ "/opt/emlrender/api.py" ]


--------------------------------------------------------------------------------
/README.md:
--------------------------------------------------------------------------------
  1 | # EMLRender
  2 | ## Introduction
  3 | Sometimes, while investigating incident implying emails, you can get a copy of the original message in [EML](http://www.forensicswiki.org/wiki/EML) format. Reading an EML file is not easy with all the SMTP headers and the mulitple MIME parts it may contain. But it may also contain suspicious code that is dangerous to be executed from sensitive environments. EMLRender is a Python script that provides a REST API to render submitted EML files into PNG images. This way, it's easy to have a clear overview of the mail content.
  4 | 
  5 | Here is a sample of generated image:
  6 | ![alt text](https://raw.githubusercontent.com/xme/emlrender/master/sample.png "Sample image")
  7 | 
  8 | ## Compoments
  9 | EMLRender is based on the [wkhtmltoimage](https://wkhtmltopdf.org/) tool to render HTML code. It consists of a single Python script that provides an HTTP interface or REST API. The best way to use it is to run it in a Docker container. This way, it can be easily deployed.
 10 | 
 11 | ## Installation
 12 | ### Building the  container
 13 | Use the provide Dockerfile to build your image:
 14 | ```
 15 | $ git clone https://github.com/xme/emlrender
 16 | $ cd emlrender
 17 | $ docker build -t emlrender:latest .
 18 | ```
 19 | An image is ready to use on hub.docker.com: [https://hub.docker.com/r/rootshell/emlrender/](https://hub.docker.com/r/rootshell/emlrender/)
 20 | 
 21 | ### Starting the container
 22 | EMLRender is a stand-alone container that does not have any dependency.
 23 | ```
 24 | $ docker run emlrender:latest
 25 | ```
 26 | Once started, it will listing to port 443. 
 27 | Note: a self-signed certificate is generated when the container is created.
 28 | 
 29 | ## Setup & Configuration
 30 | ### User database creation
 31 | EMLRender requires user authentication to render EML files. The first action is to generate the users database and an admin account:
 32 | ```
 33 | $ curl -k -X POST -d '{"password":"strongpw"}' https://127.0.0.1/init
 34 | [{"message": "Users database successfully initialized"}, {"password": "strongpw"}]
 35 | ```
 36 | If you don't specify a password, a random one will be generated:
 37 | ```
 38 | $ curl -k -X POST -d '{}' https://127.0.0.1/init
 39 | [{"message": "Users database successfully initialized"}, {"password": "1o03uqjm6w"}]
 40 | ```
 41 | 
 42 | ### User accounts management
 43 | #### Creation
 44 | New users can be added with the following request:
 45 | ```
 46 | $ curl -k -u admin:secretpw -X POST -d '{"username":"john", "password":"strongpw"}' https://127.0.0.1/users/add
 47 | [{"message": "Account successfully created", "username": "john", "password": "strongpw"}]
 48 | ```
 49 | Note: If no password is provided, a random one will be generated.
 50 | 
 51 | #### Password change
 52 | Account passwords can be changed with the following request:
 53 | ```
 54 | $ curl -k -u admin:secretpw -X POST -d '{"username":"john", "newpassword":"verystrongpw"}' https://127.0.0.1/users/resetpw
 55 | [{"message": "Password successfully updated", "username": "john", newpassword": "verystrongpw"}]
 56 | ```
 57 | Note: Regular users can change their own password.
 58 | 
 59 | #### Deletion
 60 | Users can be deleted with the following request:
 61 | ```
 62 | $ curl -k -u admin:secretpw -X POST -d '{"username":"john"}' https://127.0.0.1/users/delete
 63 | [{ "message" : "Account successfully deleted" }]
 64 | ```
 65 | 
 66 | ### Users listing
 67 | A list of users can be fetched with the following request:
 68 | ```
 69 | $ curl -k -u admin:secretpw https://127.0.0.1/users/list
 70 | [{"message": "Success"}, {"username": "admin"}, {"username": "john"}]
 71 | ```
 72 | 
 73 | ## Usage
 74 | ### Help page
 75 | A simple help page is available when you point your browser to the following URL: https://127.0.0.1/help
 76 | 
 77 | ### EML Rendering
 78 | #### REST API
 79 | To submit an EML file, use the following request:
 80 | ```
 81 | $ curl -k -u john:strongpw -F file=@"spam.eml" -o spam.png https://127.0.0.1/upload
 82 | ```
 83 | The generated picture will be saved into spam.png.
 84 | It is possible to submit a ZIP archive containing the EML file (encrypted archives are supported):
 85 | ```
 86 | $ curl -k -u john:strongpw -F file=@"malicious.zip" -F password=infected -o malicious.png https://127.0.0.1/upload
 87 | ```
 88 | 
 89 | #### Web browser
 90 | Point your browser to https://127.0.0.1/upload to submit your EML file via a normal HTML form.
 91 | 
 92 | ## Logging
 93 | ### HTTP log
 94 | A classic HTTP log is available via the Docker interface:
 95 | ```
 96 | $ docker logs -f emlrender
 97 |  * Running on https://0.0.0.0:443/ (Press CTRL+C to quit)
 98 | 172.17.0.1 - - [18/May/2018 11:59:43] "POST /init HTTP/1.1" 200 -
 99 | 172.17.0.1 - - [18/May/2018 12:06:36] "POST /users/add HTTP/1.1" 200 -
100 | 172.17.0.1 - - [18/May/2018 12:12:08] "GET /users/list HTTP/1.1" 200 -
101 | ```
102 | 
103 | The application log is available via the api.log file in the container:
104 | ```
105 | $ docker exec -it emlrender tail -f api.log
106 | [2018-May-18 11:59] 172.17.0.1 POST /init? [INFO] Init page requested
107 | [2018-May-18 11:59] 172.17.0.1 POST /init? [INFO] Users database successfully initialized
108 | [2018-May-18 12:06] 172.17.0.1 POST /users/add? [INFO] AddUser page requested
109 | [2018-May-18 12:06] 172.17.0.1 POST /users/add? [INFO] Admin authentication successful
110 | [2018-May-18 12:06] 172.17.0.1 POST /users/add? [INFO] Account john successfully created
111 | [2018-May-18 12:12] 172.17.0.1 GET /users/list? [INFO] ListUsers page requested
112 | [2018-May-18 12:12] 172.17.0.1 GET /users/list? [INFO] Accounts list successfully returned
113 | [2018-May-18 12:24] 172.17.0.1 POST /upload? [INFO] User john successfully authenticated
114 | [2018-May-18 12:24] 172.17.0.1 POST /upload? [INFO] Date: Fri, 18 May 2018 10:38:26 +0200
115 | [2018-May-18 12:24] 172.17.0.1 POST /upload? [INFO] From: <redacted>
116 | [2018-May-18 12:24] 172.17.0.1 POST /upload? [INFO] To: <redacted>
117 | [2018-May-18 12:24] 172.17.0.1 POST /upload? [INFO] Subject: <redacted>
118 | [2018-May-18 12:24] 172.17.0.1 POST /upload? [INFO] Message-Id: <redacted>
119 | [2018-May-18 12:24] 172.17.0.1 POST /upload? [INFO] Created headers 6346209b0e191fe5e9a740db4e7a2db6.png
120 | [2018-May-18 12:24] 172.17.0.1 POST /upload? [INFO] Multipart found, continue
121 | [2018-May-18 12:24] 172.17.0.1 POST /upload? [INFO] Found MIME part: text/plain
122 | [2018-May-18 12:24] 172.17.0.1 POST /upload? [INFO] Decoded 693d8cdec2a72278157ac4bb107b44b0.png
123 | [2018-May-18 12:24] 172.17.0.1 POST /upload? [INFO] Found MIME part: text/html
124 | [2018-May-18 12:24] 172.17.0.1 POST /upload? [INFO] Decoded 461c46fefa1b887857398ba17446b822.png
125 | ```
126 | 
127 | 
128 | 


--------------------------------------------------------------------------------
/api.py:
--------------------------------------------------------------------------------
  1 | #!/usr/bin/python3
  2 | #
  3 | # api.py - Flask REST API to render EML files
  4 | #
  5 | # Author: Xavier Mertens <xavier@rootshell.be>
  6 | # Copyright: GPLv3 (http://gplv3.fsf.org)
  7 | # Fell free to use the code, but please share the changes you've made
  8 | #
  9 | # Todo
 10 | # - "offline" mode when rendering HTML code
 11 | #
 12 | 
 13 | import os
 14 | import sys
 15 | import email
 16 | import email.header
 17 | import quopri
 18 | import hashlib
 19 | import logging
 20 | import base64
 21 | import zipfile
 22 | import string
 23 | import random
 24 | import json
 25 | from time import strftime
 26 | from logging.handlers import RotatingFileHandler
 27 | 
 28 | from json import dumps
 29 | 
 30 | try:
 31 |     from flask import Flask, request, jsonify, send_file, Response
 32 |     from flask_restful import Resource, Api
 33 |     from flask_httpauth import HTTPBasicAuth
 34 |     from flask_sqlalchemy import SQLAlchemy
 35 | except:
 36 |     print('[ERROR] flask module not installed ("pip install flask")')
 37 |     sys.exit(1)
 38 | 
 39 | try:
 40 |     from passlib.apps import custom_app_context as pwd_context
 41 | except:
 42 |     print('[ERROR] passlib module is not installed ("pip install passlib")')
 43 |     sys.exit(1)
 44 | 
 45 | try:
 46 |     import imgkit
 47 | except:
 48 |     print('[ERROR] imgkit module not installed ("pip install imgkit")')
 49 |     sys.exit(1)
 50 | 
 51 | try:
 52 |     from PIL import Image
 53 | except:
 54 |     print('[ERROR] pillow module not installed ("pip install pillow")')
 55 |     sys.exit(1)
 56 | 
 57 | __author__     = "Xavier Mertens"
 58 | __license__    = "GPL"
 59 | __version__    = "1.0"
 60 | __maintainer__ = "Xavier Mertens"
 61 | __email__      = "xavier@erootshell.be"
 62 | __name__       = "EMLRender"
 63 | 
 64 | app        = Flask(__name__)
 65 | api        = Api(app)
 66 | logger     = None
 67 | dumpDir    = 'dumps'
 68 | textTypes  = [ 'text/plain', 'text/html' ]
 69 | imageTypes = [ 'image/gif', 'image/jpeg', 'image/png' ]
 70 | basic_auth = HTTPBasicAuth()
 71 | 
 72 | app.config['BASIC_AUTH_REALM'] = 'EMLRender Authentication'
 73 | app.config['SQLALCHEMY_DATABASE_URI'] = 'sqlite:///auth.db'
 74 | db = SQLAlchemy(app)
 75 | 
 76 | class User(db.Model):
 77 |     __tablename__ = 'users'
 78 |     uid           = db.Column(db.Integer, primary_key = True)
 79 |     username      = db.Column(db.String(32), index = True)
 80 |     password_hash = db.Column(db.String(128))
 81 | 
 82 |     def hash_password(self, password):
 83 |         self.password_hash = pwd_context.encrypt(password)
 84 | 
 85 |     def verify_password(self, password):
 86 |         return pwd_context.verify(password, self.password_hash)
 87 | 
 88 | @basic_auth.verify_password
 89 | def verify_password(username, password):
 90 |     try:
 91 |         user = User.query.filter_by(username = username).first()
 92 |         if not user or not user.verify_password(password):
 93 |             return False
 94 |         else:
 95 |             return True
 96 |     except:
 97 |        writeLog('[ERROR] SQL query failed (DB not initialized?)')
 98 |        return False
 99 | 
100 | def writeLog(msg):
101 | 
102 |     '''
103 |     Use logger() to write an event log
104 |     '''
105 | 
106 |     ts = strftime('[%Y-%b-%d %H:%M]')
107 |     logger.error('%s %s %s %s %s',
108 |         ts,
109 |         request.remote_addr,
110 |         request.method,
111 |         request.full_path,
112 |         msg)
113 | 
114 | def appendImages(images):
115 |     bgColor=(255,255,255)
116 |     widths, heights = zip(*(i.size for i in images))
117 | 
118 |     new_width = max(widths)
119 |     new_height = sum(heights)
120 |     new_im = Image.new('RGB', (new_width, new_height), color = bgColor)
121 |     offset = 0
122 |     for im in images:
123 |         # x = int((new_width - im.size[0])/2)
124 |         x = 0
125 |         new_im.paste(im, (x, offset))
126 |         offset += im.size[1]
127 |     return new_im
128 | 
129 | def extractEmail(string):
130 |     match = re.match('.*\<(\S+)\>.*', string)
131 |     if match:
132 |         return match.group(1)
133 |     else:
134 |         return None
135 | 
136 | def processEml(data):
137 | 
138 |     '''
139 |     Process the email (bytes), extract MIME parts and useful headers.
140 |     Generate a PNG picture of the mail
141 |     '''
142 | 
143 |     # Create the dump directory if not existing yet
144 |     if not os.path.isdir(dumpDir):
145 |         os.makedirs(dumpDir)
146 |         writeLog("[INFO] Created dump directory %s" % dumpDir)
147 | 
148 |     msg = email.message_from_bytes(data)
149 |     try:
150 |         decode = email.header.decode_header(msg['Date'])[0]
151 |         dateField = str(decode[0])
152 |     except:
153 |         dateField = '&lt;Unknown&gt;'
154 |     writeLog('[INFO] Date: %s' % dateField)
155 | 
156 |     try:
157 |         decode = email.header.decode_header(msg['From'])[0]
158 |         fromField = str(decode[0])
159 |     except:
160 |         fromField = '&lt;Unknown&gt;'
161 |     writeLog('[INFO] From: %s' %  fromField)
162 |     fromField = fromField.replace('<', '&lt;').replace('>', '&gt;')
163 | 
164 |     try:
165 |         decode = email.header.decode_header(msg['To'])[0]
166 |         toField = str(decode[0])
167 |     except:
168 |         toField = '&lt;Unknown&gt;'
169 |     writeLog('[INFO] To: %s' % toField)
170 |     toField = toField.replace('<', '&lt;').replace('>', '&gt;')
171 | 
172 |     try:
173 |         decode = email.header.decode_header(msg['Subject'])[0]
174 |         subjectField = str(decode[0])
175 |     except:
176 |         subjectField = '&lt;Unknown&gt;'
177 |     writeLog('[INFO] Subject: %s' % subjectField)
178 |     subjectField = subjectField.replace('<', '&lt;').replace('>', '&gt;')
179 | 
180 |     try:
181 |         decode = email.header.decode_header(msg['Message-Id'])[0]
182 |         idField = str(decode[0])
183 |     except:
184 |         idField = '&lt;Unknown&gt;'
185 |     writeLog('[INFO] Message-Id: %s' % idField)
186 |     idField = idField.replace('<', '&lt;').replace('>', '&gt;')    
187 | 
188 |     imgkitOptions = { 'load-error-handling': 'skip'}
189 |     # imgkitOptions.update({ 'quiet': None })
190 |     imagesList = []
191 |     attachments = []
192 | 
193 |     # Build a first image with basic mail details
194 |     headers = '''
195 |     <table width="100%%">
196 |       <tr><td align="right"><b>Date:</b></td><td>%s</td></tr>
197 |       <tr><td align="right"><b>From:</b></td><td>%s</td></tr>
198 |       <tr><td align="right"><b>To:</b></td><td>%s</td></tr>
199 |       <tr><td align="right"><b>Subject:</b></td><td>%s</td></tr>
200 |       <tr><td align="right"><b>Message-Id:</b></td><td>%s</td></tr>
201 |     </table>
202 |     <hr></p>
203 |     ''' % (dateField, fromField, toField, subjectField, idField)
204 |     m = hashlib.md5()
205 |     m.update(headers.encode('utf-8'))
206 |     imagePath = m.hexdigest() + '.png'
207 |     try:
208 |         imgkit.from_string(headers, dumpDir + '/' + imagePath, options = imgkitOptions)
209 |         writeLog('[INFO] Created headers %s' % imagePath)
210 |         imagesList.append(dumpDir + '/' + imagePath)
211 |     except:
212 |         writeLog('[WARNING] Creation of headers failed')
213 | 
214 |     #
215 |     # Main loop - process the MIME parts
216 |     #
217 |     for part in msg.walk():
218 |         mimeType = part.get_content_type()
219 |         if part.is_multipart():
220 |             writeLog('[INFO] Multipart found, continue')
221 |             continue
222 | 
223 |         writeLog('[INFO] Found MIME part: %s' % mimeType)
224 |         if mimeType in textTypes:
225 |             try:
226 |                 payload = quopri.decodestring(part.get_payload(decode=True)).decode('utf-8')
227 |             except:
228 |                 payload = str(quopri.decodestring(part.get_payload(decode=True)))[2:-1]
229 |             
230 |             # Cleanup dirty characters
231 |             dirtyChars = [ '\n', '\\n', '\t', '\\t', '\r', '\\r']
232 |             for char in dirtyChars:
233 |                 payload = payload.replace(char, '')
234 |             
235 |             # Generate MD5 hash of the payload
236 |             m = hashlib.md5()
237 |             m.update(payload.encode('utf-8'))
238 |             imagePath = m.hexdigest() + '.png'
239 |             try:
240 |                 imgkit.from_string(payload, dumpDir + '/' + imagePath, options = imgkitOptions)
241 |                 writeLog('[INFO] Decoded %s' % imagePath)
242 |                 imagesList.append(dumpDir + '/' + imagePath)
243 |             except:
244 |                 writeLog('[WARNING] Decoding this MIME part returned error')
245 |         elif mimeType in imageTypes:
246 |             payload = part.get_payload(decode=False)
247 |             imgdata = base64.b64decode(payload)
248 |             # Generate MD5 hash of the payload
249 |             m = hashlib.md5()
250 |             m.update(payload.encode('utf-8'))
251 |             imagePath = m.hexdigest() + '.' + mimeType.split('/')[1]
252 |             try:
253 |                 with open(dumpDir + '/' + imagePath, 'wb') as f:
254 |                     f.write(imgdata)
255 |                 writeLog('[INFO] Decoded %s' % imagePath)
256 |                 imagesList.append(dumpDir + '/' + imagePath)
257 |             except:
258 |                 writeLog('[WARNING] Decoding this MIME part returned error')
259 |         else:
260 |             fileName = part.get_filename()
261 |             if not fileName:
262 |                 fileName = "Unknown"
263 |             attachments.append("%s (%s)" % (fileName, mimeType))
264 |             writeLog('[INFO] Skipped attachment %s (%s)' % (fileName, mimeType))
265 | 
266 |     if len(attachments):
267 |         footer = '<p><hr><p><b>Attached Files:</b><p><ul>'
268 |         for a in attachments:
269 |             footer = footer + '<li>' + a + '</li>'
270 |         footer = footer + '</ul><p><br>Generated by EMLRender v1.0'
271 |         m = hashlib.md5()
272 |         m.update(footer.encode('utf-8'))
273 |         imagePath = m.hexdigest() + '.png'
274 |         try:
275 |             imgkit.from_string(footer, dumpDir + '/' + imagePath, options = imgkitOptions)
276 |             writeLog('[INFO] Created footer %s' % imagePath)
277 |             imagesList.append(dumpDir + '/' + imagePath)
278 |         except:
279 |             writeLog('[WARNING] Creation of footer failed')
280 | 
281 |     resultImage = dumpDir + '/' + 'new.png'
282 |     if len(imagesList) > 0:
283 |         images = list(map(Image.open, imagesList))
284 |         combo = appendImages(images)
285 |         combo.save(resultImage)
286 |         # Clean up temporary images
287 |         for i in imagesList:
288 |            os.remove(i)
289 |         return(resultImage)
290 |     else:
291 |         return(False)
292 | 
293 | class Upload(Resource):
294 | 
295 |     '''
296 |     Handle the upload of an EML file.
297 |     Supported files are flat files or ZIP archive (encrypted or not)
298 |     The function supports the REST API or a classic form POST.
299 |     '''
300 | 
301 |     @basic_auth.login_required
302 |     def post(self):
303 |         writeLog('[INFO] User %s successfully authenticated' % request.authorization.username)
304 | 
305 |         if 'file' not in request.files:
306 |             return {"message": "No file found"}
307 |         file = request.files['file']
308 |         #
309 |         # Support for ZIP files:
310 |         #
311 |         if zipfile.is_zipfile(file):
312 |             writeLog('[INFO] Uploaded file is a zip archive')
313 |             zpw = request.form.get('password')
314 |             zfd = zipfile.ZipFile(file)
315 |             zfile = zfd.namelist()[0]
316 |             #
317 |             # TODO: Support multiple files in the zip file, 
318 |             # Now, only process the 1st one
319 |             #
320 |             try:
321 |                 if zpw:
322 |                     writeLog('[INFO] Zip password provided: %s' % zpw)
323 |                 zbytes = zfd.read(zfile, pwd=bytes(zpw,'utf-8'))
324 |             except:
325 |                 writeLog('[ERROR] Cannot unzip file: %s' % zfile)
326 |                 return Response(json.dumps([{"message": "Cannot process the ZIP file" % zfile}]), mimetype='application/json')
327 |             image = processEml(zbytes)
328 |         else:
329 |             # This is a regular EML file
330 |             # Bug? File has been read by ZipFile.read(), restart from byte 0!
331 |             file.seek(0)
332 |             image = processEml(file.read())
333 | 
334 |         if image:
335 |             return send_file(image)
336 |         else:
337 |             return Response(json.dump([{"message": "Cannot process the EML file"}]), mimetype='application/json')
338 | 
339 |     def get(self):
340 |         writeLog('[INFO] Upload page requested')
341 | 
342 |         return Response('''
343 |         <!doctype html>
344 |         <title>EMLRender: Upload new EML File</title>
345 |         <h1>EMLRender</h1>
346 |         Upload new File:
347 |         <form method=post enctype=multipart/form-data>
348 |         <p>
349 |         EML File or ZIP Archive: <input type=file name=file></br>
350 |         ZIP Password (optional): <input type=text name="password" size=20>
351 |         <br>
352 |         <input type=submit value=Upload>
353 |         </form>
354 |         ''', mimetype='text/html')
355 | 
356 | class Root(Resource):
357 |     def get(self):
358 |         writeLog('[INFO] Root page requested')
359 | 
360 |         return Response('''
361 |         <!doctype html>
362 |         <title>EMLRender</title>
363 |         Please upload a file via <a href="/upload">/upload</a> or read the <a href="/help">/help</a>.
364 |         ''', mimetype='text/html')
365 | 
366 | class Help(Resource):
367 |     def get(self):
368 |         writeLog('[INFO] Help page displayed')
369 |         return Response('''
370 |             <!doctype html>
371 |             <title>EMLRender</title>
372 |             <h1>EMLRender</h1>
373 |             This web service renders email files submitted in EML[1] format. Files can be <a href="/upload">uploaded</a> with a browser or via a REST API interface. The output is a PNG image.</br>
374 |             The EML File can be uploaded in a ZIP archive (with optional password).
375 |             <p>
376 |             The following commands are available:
377 |             <ul>
378 |             <li<GET /help</li>
379 |             <li>POST /upload</li>
380 |             <li>POST /init (Initialize the users database)</li>
381 |             <li>POST /users/add (Create a user admin)</li>
382 |             <li>POST /users/resetpw (Change a user's password)</li>
383 |             <li>POST /users/delete (Remove a user account)</li>
384 |             </ul>
385 |             Examples of usage:
386 |             <pre>$ curl -u user:password -F file=@"spam.eml" -o result.png http://server.domain.com/upload</pre>
387 |             <pre>$ curl -u user:password -F file=@"malicious.zip" -F password=infected -o result.png http://server.domain.com/upload</pre>
388 |             <pre>$ curl -u admin:password -X POST -d "{'username':'john'}" https://server.domain.com/users/add</pre>
389 |             <p>
390 |             [1] Used by many email clients including Novell GroupWise, Microsoft Outlook Express, Lotus notes, Windows Mail, Mozilla Thunderbird, and Postbox. EML files contain the email as plain text in MIME format, containing the email header and body, including attachments in one or more of several formats.
391 |             ''', mimetype='text/html')
392 | 
393 | class Init(Resource):
394 | 
395 |     '''
396 |     Generate the initial 'admin' account. 
397 |     Creates a password and a token in the database without authentication.
398 |     If the user 'admin' already exists returns an error
399 | 
400 |     Parameters:
401 |     - password: The admin password to create
402 |     '''
403 | 
404 |     def post(self):
405 |         writeLog('[INFO] Init page requested')
406 | 
407 |         username = 'admin'
408 |         if User.query.filter_by(username = username).first() is not None:
409 |             writeLog('[ERROR] Users database already initialized')
410 |             return Response(json.dumps([{ "message" : "The users database has already been initialized" }]), mimetype='application/json')
411 | 
412 |         request_json = request.get_json(force=True)
413 |         password = request_json.get('password')
414 |         if password is None:
415 |             # Generate a random 10 characters password
416 |             password = ''.join(random.choice(string.ascii_lowercase + string.digits) for _ in range(10)).encode('utf-8')
417 |         
418 |         user  = User(username = username)
419 |         user.hash_password(password)
420 |         db.session.add(user)
421 |         db.session.commit()
422 | 
423 |         writeLog('[INFO] Users database successfully initialized')
424 |         return Response(json.dumps([{ "message" : "Users database successfully initialized" }, {"password" : password}]), mimetype='application/json')
425 | 
426 | class AddUser(Resource):
427 | 
428 |     '''
429 |     Create a new user in the database (restricted to the 'admin' user)
430 |     Note: if no password is provided, a random password is generated
431 |     Example:
432 |     $ curl -u admin:pass -X POST -d {'username':'foo','password':'bar'} https://127.0.0.1/users/add
433 |     '''
434 | 
435 |     @basic_auth.login_required
436 | 
437 |     def post(self):
438 |         writeLog('[INFO] AddUser page requested')
439 | 
440 |         # Restrict access to admin
441 |         if request.authorization.username != 'admin':
442 |             writeLog('[WARNING] Access denied')
443 |             return Response(json.dumps([{ "message" : "Access denied" }]), mimetype='application/json')
444 |         else:
445 |             writeLog('[INFO] Admin authentication successful')
446 | 
447 |         # Use this to load JSON data event if the mimetype of not correctly set
448 |         request_json = request.get_json(force=True)
449 |         username = request_json.get('username')
450 |         password = request_json.get('password')
451 |         if username is None:
452 |             writelog('[ERROR] Missing username parameter')
453 |             return Response(json.dump([{ "message" : "Missing username parameter" }]), mimetype='application/json')
454 | 
455 |         if password is None:
456 |             # Generate a random 10 characters password
457 |             passsword = ''.join(random.choice(string.ascii_lowercase + string.digits) for _ in range(10)).encode('utf-8')
458 | 
459 |         if User.query.filter_by(username = username).first() is not None:
460 |             writeLog('[ERROR] Users already exists: %s' % username)
461 |             return Response(json.dumps([{ "message" : "User already exists" }]), mimetype='application/json')
462 | 
463 |         user  = User(username = username)
464 |         user.hash_password(password)
465 |         db.session.add(user)
466 |         db.session.commit()
467 | 
468 |         writeLog('[INFO] Account %s successfully created' % username)
469 |         return Response(json.dumps([{ "message" : "Account successfully created", "username" : username, "password" : password }]), mimetype='application/json')
470 | 
471 | class ResetPw(Resource):
472 | 
473 |     '''
474 |     Reset a user's password
475 |     Note: if no password is provided, a random password is generated
476 |     Example:
477 |     $ curl -u admin:pass -X POST -d '{"username":"user", "newpassword":"setcretpw"}'' https://127.0.0.1/users/add
478 |     '''
479 | 
480 |     @basic_auth.login_required
481 | 
482 |     def post(self):
483 |         writeLog('[INFO] ResetPw page requested')
484 | 
485 |         isAdmin = False
486 | 
487 |         # Are we admin? Only the admin can change any password
488 |         if request.authorization.username == 'admin':
489 |             isAdmin = True
490 |             writeLog('[INFO] Admin successfully authenticated')
491 |         else:
492 |             writeLog('[INFO] User %s successfully authenticated' % request.authorization.username)
493 | 
494 |         # Use this to load JSON data event if the mimetype of not correctly set
495 |         request_json = request.get_json(force=True)
496 |         username = request_json.get('username')
497 |         newpassword = request_json.get('newpassword')
498 |         if username is None:
499 |             writelog('[ERROR] Missing username parameter')
500 |             return Response(json.dumps([{ "message" : "Missing username parameter" }]), mimetype='application/json')
501 | 
502 |         if username == 'admin' and isAdmin == False:
503 |             writeLog('[ERROR] Admin password change rejected')
504 |             return Response(json.dumps([{ "message" : "Access denied" }]), mimetype='application/json')
505 | 
506 |         if newpassword is None:
507 |             # Generate a random 10 characters password
508 |             newpassword = ''.join(random.choice(string.ascii_lowercase + string.digits) for _ in range(10)).encode('utf-8')
509 | 
510 |         if User.query.filter_by(username = username).first() is None:
511 |             writeLog('[ERROR] Users %s do not exist: %s' % username)
512 |             return Response(json.dumps([{ "message" : "User do not exist" }]), mimetype='application/json')
513 |        
514 |         user  = User(username = username)
515 |         user.hash_password(newpassword)
516 |         db.session.commit()
517 | 
518 |         writeLog('[INFO] Password successfully updated: %s' % username)
519 |         return Response(json.dumps([{ "message" : "Password successfully updated", "username" : username, "password" : newpassword }]), mimetype='application/json')
520 | 
521 | class DeleteUser(Resource):
522 | 
523 |     '''
524 |     Delete  a user account
525 |     Only allowed to admin
526 |     Example:
527 |     $ curl -u admin:pass -X POST -d '{"username":"user"}' https://127.0.0.1/users/delete
528 |     '''
529 | 
530 |     @basic_auth.login_required
531 | 
532 |     def post(self):
533 |         writeLog('[INFO] DeleteUser page requested')
534 | 
535 |         # Only admin can remove an account
536 |         if request.authorization.username != 'admin':
537 |             writeLog('[ERROR] Access denied')
538 |             return Response(json.dumps([{ "message" : "Access denied" }]), mimetype='application/json')
539 | 
540 |         # Use this to load JSON data event if the mimetype of not correctly set
541 |         request_json = request.get_json(force=True)
542 |         username = request_json.get('username')
543 |         if username is None:
544 |             writelog('[ERROR] Missing username parameter')
545 |             return Response(json.dumps([{ "message" : "Missing username parameter" }]), mimetype='application/json')
546 | 
547 |         if username == 'admin':
548 |             writeLog('[ERROR] Admin account cannott be deleted')
549 |             return Response(json.dumps([{ "message" : "Account cannot be deleted" }]), mimetype='application/json')
550 | 
551 |         if User.query.filter_by(username = username).first() is None:
552 |             writeLog('[ERROR] Account %s do not exist: %s' % username)
553 |             return Response(json.dumps([{ "message" : "Account do not exist" }]), mimetype='application/json')
554 | 
555 |         User.query.filter_by(username = username).delete()
556 |         db.session.commit()
557 | 
558 |         writeLog('[INFO] Account %s  successfully deleted' % username)
559 |         return Response(json.dumps([{ "message" : "Account successfully deleted" }]), mimetype='application/json')
560 | 
561 | class ListUsers(Resource):
562 | 
563 |     '''
564 |     List accounts (Only allowed to admin)
565 |     Example:
566 |     $ curl -u admin:pass https://127.0.0.1/users/list
567 |     '''
568 | 
569 |     @basic_auth.login_required
570 | 
571 |     def get(self):
572 |         writeLog('[INFO] ListUsers page requested')
573 | 
574 |         # Only admin can list accounts
575 |         if request.authorization.username != 'admin':
576 |             writeLog('[ERROR] Access denied')
577 |             return Response(json.dumps([{ "message" : "Access denied" }]), mimetype='application/json')
578 | 
579 |         jsondata = [{ "message" : "Success" }]
580 |         users = User.query.all()
581 |         for user in users:
582 |             jsondata.append({"username" : user.username})
583 | 
584 |         writeLog('[INFO] Accounts list successfully returned')
585 |         return Response(json.dumps(jsondata),  mimetype='application/json')
586 | 
587 | def main():
588 |     global logger
589 | 
590 |     # Create the initial database
591 |     db.create_all()
592 | 
593 |     api.add_resource(Root, '/')
594 |     api.add_resource(Upload, '/upload')
595 |     api.add_resource(Help, '/help')
596 |     api.add_resource(Init, '/init')
597 |     api.add_resource(ListUsers, '/users/list')
598 |     api.add_resource(AddUser, '/users/add')
599 |     api.add_resource(DeleteUser, '/users/delete')
600 |     api.add_resource(ResetPw, '/users/resetpw')
601 |     handler = RotatingFileHandler('api.log', maxBytes=50000, backupCount=5)
602 |     logger = logging.getLogger(__name__)
603 |     logger.setLevel(logging.ERROR)
604 |     logger.addHandler(handler)
605 |     app.run(host='0.0.0.0', port=443, ssl_context='adhoc')
606 | 
607 | if __name__ == 'EMLRender':
608 |     main()
609 |     sys.exit(0)
610 | 


--------------------------------------------------------------------------------
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--------------------------------------------------------------------------------
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  2 |                        Version 3, 29 June 2007
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307 | commercial, industrial or non-consumer uses, unless such uses represent
308 | the only significant mode of use of the product.
309 | 
310 |   "Installation Information" for a User Product means any methods,
311 | procedures, authorization keys, or other information required to install
312 | and execute modified versions of a covered work in that User Product from
313 | a modified version of its Corresponding Source.  The information must
314 | suffice to ensure that the continued functioning of the modified object
315 | code is in no case prevented or interfered with solely because
316 | modification has been made.
317 | 
318 |   If you convey an object code work under this section in, or with, or
319 | specifically for use in, a User Product, and the conveying occurs as
320 | part of a transaction in which the right of possession and use of the
321 | User Product is transferred to the recipient in perpetuity or for a
322 | fixed term (regardless of how the transaction is characterized), the
323 | Corresponding Source conveyed under this section must be accompanied
324 | by the Installation Information.  But this requirement does not apply
325 | if neither you nor any third party retains the ability to install
326 | modified object code on the User Product (for example, the work has
327 | been installed in ROM).
328 | 
329 |   The requirement to provide Installation Information does not include a
330 | requirement to continue to provide support service, warranty, or updates
331 | for a work that has been modified or installed by the recipient, or for
332 | the User Product in which it has been modified or installed.  Access to a
333 | network may be denied when the modification itself materially and
334 | adversely affects the operation of the network or violates the rules and
335 | protocols for communication across the network.
336 | 
337 |   Corresponding Source conveyed, and Installation Information provided,
338 | in accord with this section must be in a format that is publicly
339 | documented (and with an implementation available to the public in
340 | source code form), and must require no special password or key for
341 | unpacking, reading or copying.
342 | 
343 |   7. Additional Terms.
344 | 
345 |   "Additional permissions" are terms that supplement the terms of this
346 | License by making exceptions from one or more of its conditions.
347 | Additional permissions that are applicable to the entire Program shall
348 | be treated as though they were included in this License, to the extent
349 | that they are valid under applicable law.  If additional permissions
350 | apply only to part of the Program, that part may be used separately
351 | under those permissions, but the entire Program remains governed by
352 | this License without regard to the additional permissions.
353 | 
354 |   When you convey a copy of a covered work, you may at your option
355 | remove any additional permissions from that copy, or from any part of
356 | it.  (Additional permissions may be written to require their own
357 | removal in certain cases when you modify the work.)  You may place
358 | additional permissions on material, added by you to a covered work,
359 | for which you have or can give appropriate copyright permission.
360 | 
361 |   Notwithstanding any other provision of this License, for material you
362 | add to a covered work, you may (if authorized by the copyright holders of
363 | that material) supplement the terms of this License with terms:
364 | 
365 |     a) Disclaiming warranty or limiting liability differently from the
366 |     terms of sections 15 and 16 of this License; or
367 | 
368 |     b) Requiring preservation of specified reasonable legal notices or
369 |     author attributions in that material or in the Appropriate Legal
370 |     Notices displayed by works containing it; or
371 | 
372 |     c) Prohibiting misrepresentation of the origin of that material, or
373 |     requiring that modified versions of such material be marked in
374 |     reasonable ways as different from the original version; or
375 | 
376 |     d) Limiting the use for publicity purposes of names of licensors or
377 |     authors of the material; or
378 | 
379 |     e) Declining to grant rights under trademark law for use of some
380 |     trade names, trademarks, or service marks; or
381 | 
382 |     f) Requiring indemnification of licensors and authors of that
383 |     material by anyone who conveys the material (or modified versions of
384 |     it) with contractual assumptions of liability to the recipient, for
385 |     any liability that these contractual assumptions directly impose on
386 |     those licensors and authors.
387 | 
388 |   All other non-permissive additional terms are considered "further
389 | restrictions" within the meaning of section 10.  If the Program as you
390 | received it, or any part of it, contains a notice stating that it is
391 | governed by this License along with a term that is a further
392 | restriction, you may remove that term.  If a license document contains
393 | a further restriction but permits relicensing or conveying under this
394 | License, you may add to a covered work material governed by the terms
395 | of that license document, provided that the further restriction does
396 | not survive such relicensing or conveying.
397 | 
398 |   If you add terms to a covered work in accord with this section, you
399 | must place, in the relevant source files, a statement of the
400 | additional terms that apply to those files, or a notice indicating
401 | where to find the applicable terms.
402 | 
403 |   Additional terms, permissive or non-permissive, may be stated in the
404 | form of a separately written license, or stated as exceptions;
405 | the above requirements apply either way.
406 | 
407 |   8. Termination.
408 | 
409 |   You may not propagate or modify a covered work except as expressly
410 | provided under this License.  Any attempt otherwise to propagate or
411 | modify it is void, and will automatically terminate your rights under
412 | this License (including any patent licenses granted under the third
413 | paragraph of section 11).
414 | 
415 |   However, if you cease all violation of this License, then your
416 | license from a particular copyright holder is reinstated (a)
417 | provisionally, unless and until the copyright holder explicitly and
418 | finally terminates your license, and (b) permanently, if the copyright
419 | holder fails to notify you of the violation by some reasonable means
420 | prior to 60 days after the cessation.
421 | 
422 |   Moreover, your license from a particular copyright holder is
423 | reinstated permanently if the copyright holder notifies you of the
424 | violation by some reasonable means, this is the first time you have
425 | received notice of violation of this License (for any work) from that
426 | copyright holder, and you cure the violation prior to 30 days after
427 | your receipt of the notice.
428 | 
429 |   Termination of your rights under this section does not terminate the
430 | licenses of parties who have received copies or rights from you under
431 | this License.  If your rights have been terminated and not permanently
432 | reinstated, you do not qualify to receive new licenses for the same
433 | material under section 10.
434 | 
435 |   9. Acceptance Not Required for Having Copies.
436 | 
437 |   You are not required to accept this License in order to receive or
438 | run a copy of the Program.  Ancillary propagation of a covered work
439 | occurring solely as a consequence of using peer-to-peer transmission
440 | to receive a copy likewise does not require acceptance.  However,
441 | nothing other than this License grants you permission to propagate or
442 | modify any covered work.  These actions infringe copyright if you do
443 | not accept this License.  Therefore, by modifying or propagating a
444 | covered work, you indicate your acceptance of this License to do so.
445 | 
446 |   10. Automatic Licensing of Downstream Recipients.
447 | 
448 |   Each time you convey a covered work, the recipient automatically
449 | receives a license from the original licensors, to run, modify and
450 | propagate that work, subject to this License.  You are not responsible
451 | for enforcing compliance by third parties with this License.
452 | 
453 |   An "entity transaction" is a transaction transferring control of an
454 | organization, or substantially all assets of one, or subdividing an
455 | organization, or merging organizations.  If propagation of a covered
456 | work results from an entity transaction, each party to that
457 | transaction who receives a copy of the work also receives whatever
458 | licenses to the work the party's predecessor in interest had or could
459 | give under the previous paragraph, plus a right to possession of the
460 | Corresponding Source of the work from the predecessor in interest, if
461 | the predecessor has it or can get it with reasonable efforts.
462 | 
463 |   You may not impose any further restrictions on the exercise of the
464 | rights granted or affirmed under this License.  For example, you may
465 | not impose a license fee, royalty, or other charge for exercise of
466 | rights granted under this License, and you may not initiate litigation
467 | (including a cross-claim or counterclaim in a lawsuit) alleging that
468 | any patent claim is infringed by making, using, selling, offering for
469 | sale, or importing the Program or any portion of it.
470 | 
471 |   11. Patents.
472 | 
473 |   A "contributor" is a copyright holder who authorizes use under this
474 | License of the Program or a work on which the Program is based.  The
475 | work thus licensed is called the contributor's "contributor version".
476 | 
477 |   A contributor's "essential patent claims" are all patent claims
478 | owned or controlled by the contributor, whether already acquired or
479 | hereafter acquired, that would be infringed by some manner, permitted
480 | by this License, of making, using, or selling its contributor version,
481 | but do not include claims that would be infringed only as a
482 | consequence of further modification of the contributor version.  For
483 | purposes of this definition, "control" includes the right to grant
484 | patent sublicenses in a manner consistent with the requirements of
485 | this License.
486 | 
487 |   Each contributor grants you a non-exclusive, worldwide, royalty-free
488 | patent license under the contributor's essential patent claims, to
489 | make, use, sell, offer for sale, import and otherwise run, modify and
490 | propagate the contents of its contributor version.
491 | 
492 |   In the following three paragraphs, a "patent license" is any express
493 | agreement or commitment, however denominated, not to enforce a patent
494 | (such as an express permission to practice a patent or covenant not to
495 | sue for patent infringement).  To "grant" such a patent license to a
496 | party means to make such an agreement or commitment not to enforce a
497 | patent against the party.
498 | 
499 |   If you convey a covered work, knowingly relying on a patent license,
500 | and the Corresponding Source of the work is not available for anyone
501 | to copy, free of charge and under the terms of this License, through a
502 | publicly available network server or other readily accessible means,
503 | then you must either (1) cause the Corresponding Source to be so
504 | available, or (2) arrange to deprive yourself of the benefit of the
505 | patent license for this particular work, or (3) arrange, in a manner
506 | consistent with the requirements of this License, to extend the patent
507 | license to downstream recipients.  "Knowingly relying" means you have
508 | actual knowledge that, but for the patent license, your conveying the
509 | covered work in a country, or your recipient's use of the covered work
510 | in a country, would infringe one or more identifiable patents in that
511 | country that you have reason to believe are valid.
512 | 
513 |   If, pursuant to or in connection with a single transaction or
514 | arrangement, you convey, or propagate by procuring conveyance of, a
515 | covered work, and grant a patent license to some of the parties
516 | receiving the covered work authorizing them to use, propagate, modify
517 | or convey a specific copy of the covered work, then the patent license
518 | you grant is automatically extended to all recipients of the covered
519 | work and works based on it.
520 | 
521 |   A patent license is "discriminatory" if it does not include within
522 | the scope of its coverage, prohibits the exercise of, or is
523 | conditioned on the non-exercise of one or more of the rights that are
524 | specifically granted under this License.  You may not convey a covered
525 | work if you are a party to an arrangement with a third party that is
526 | in the business of distributing software, under which you make payment
527 | to the third party based on the extent of your activity of conveying
528 | the work, and under which the third party grants, to any of the
529 | parties who would receive the covered work from you, a discriminatory
530 | patent license (a) in connection with copies of the covered work
531 | conveyed by you (or copies made from those copies), or (b) primarily
532 | for and in connection with specific products or compilations that
533 | contain the covered work, unless you entered into that arrangement,
534 | or that patent license was granted, prior to 28 March 2007.
535 | 
536 |   Nothing in this License shall be construed as excluding or limiting
537 | any implied license or other defenses to infringement that may
538 | otherwise be available to you under applicable patent law.
539 | 
540 |   12. No Surrender of Others' Freedom.
541 | 
542 |   If conditions are imposed on you (whether by court order, agreement or
543 | otherwise) that contradict the conditions of this License, they do not
544 | excuse you from the conditions of this License.  If you cannot convey a
545 | covered work so as to satisfy simultaneously your obligations under this
546 | License and any other pertinent obligations, then as a consequence you may
547 | not convey it at all.  For example, if you agree to terms that obligate you
548 | to collect a royalty for further conveying from those to whom you convey
549 | the Program, the only way you could satisfy both those terms and this
550 | License would be to refrain entirely from conveying the Program.
551 | 
552 |   13. Use with the GNU Affero General Public License.
553 | 
554 |   Notwithstanding any other provision of this License, you have
555 | permission to link or combine any covered work with a work licensed
556 | under version 3 of the GNU Affero General Public License into a single
557 | combined work, and to convey the resulting work.  The terms of this
558 | License will continue to apply to the part which is the covered work,
559 | but the special requirements of the GNU Affero General Public License,
560 | section 13, concerning interaction through a network will apply to the
561 | combination as such.
562 | 
563 |   14. Revised Versions of this License.
564 | 
565 |   The Free Software Foundation may publish revised and/or new versions of
566 | the GNU General Public License from time to time.  Such new versions will
567 | be similar in spirit to the present version, but may differ in detail to
568 | address new problems or concerns.
569 | 
570 |   Each version is given a distinguishing version number.  If the
571 | Program specifies that a certain numbered version of the GNU General
572 | Public License "or any later version" applies to it, you have the
573 | option of following the terms and conditions either of that numbered
574 | version or of any later version published by the Free Software
575 | Foundation.  If the Program does not specify a version number of the
576 | GNU General Public License, you may choose any version ever published
577 | by the Free Software Foundation.
578 | 
579 |   If the Program specifies that a proxy can decide which future
580 | versions of the GNU General Public License can be used, that proxy's
581 | public statement of acceptance of a version permanently authorizes you
582 | to choose that version for the Program.
583 | 
584 |   Later license versions may give you additional or different
585 | permissions.  However, no additional obligations are imposed on any
586 | author or copyright holder as a result of your choosing to follow a
587 | later version.
588 | 
589 |   15. Disclaimer of Warranty.
590 | 
591 |   THERE IS NO WARRANTY FOR THE PROGRAM, TO THE EXTENT PERMITTED BY
592 | APPLICABLE LAW.  EXCEPT WHEN OTHERWISE STATED IN WRITING THE COPYRIGHT
593 | HOLDERS AND/OR OTHER PARTIES PROVIDE THE PROGRAM "AS IS" WITHOUT WARRANTY
594 | OF ANY KIND, EITHER EXPRESSED OR IMPLIED, INCLUDING, BUT NOT LIMITED TO,
595 | THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
596 | PURPOSE.  THE ENTIRE RISK AS TO THE QUALITY AND PERFORMANCE OF THE PROGRAM
597 | IS WITH YOU.  SHOULD THE PROGRAM PROVE DEFECTIVE, YOU ASSUME THE COST OF
598 | ALL NECESSARY SERVICING, REPAIR OR CORRECTION.
599 | 
600 |   16. Limitation of Liability.
601 | 
602 |   IN NO EVENT UNLESS REQUIRED BY APPLICABLE LAW OR AGREED TO IN WRITING
603 | WILL ANY COPYRIGHT HOLDER, OR ANY OTHER PARTY WHO MODIFIES AND/OR CONVEYS
604 | THE PROGRAM AS PERMITTED ABOVE, BE LIABLE TO YOU FOR DAMAGES, INCLUDING ANY
605 | GENERAL, SPECIAL, INCIDENTAL OR CONSEQUENTIAL DAMAGES ARISING OUT OF THE
606 | USE OR INABILITY TO USE THE PROGRAM (INCLUDING BUT NOT LIMITED TO LOSS OF
607 | DATA OR DATA BEING RENDERED INACCURATE OR LOSSES SUSTAINED BY YOU OR THIRD
608 | PARTIES OR A FAILURE OF THE PROGRAM TO OPERATE WITH ANY OTHER PROGRAMS),
609 | EVEN IF SUCH HOLDER OR OTHER PARTY HAS BEEN ADVISED OF THE POSSIBILITY OF
610 | SUCH DAMAGES.
611 | 
612 |   17. Interpretation of Sections 15 and 16.
613 | 
614 |   If the disclaimer of warranty and limitation of liability provided
615 | above cannot be given local legal effect according to their terms,
616 | reviewing courts shall apply local law that most closely approximates
617 | an absolute waiver of all civil liability in connection with the
618 | Program, unless a warranty or assumption of liability accompanies a
619 | copy of the Program in return for a fee.
620 | 
621 |                      END OF TERMS AND CONDITIONS
622 | 
623 |             How to Apply These Terms to Your New Programs
624 | 
625 |   If you develop a new program, and you want it to be of the greatest
626 | possible use to the public, the best way to achieve this is to make it
627 | free software which everyone can redistribute and change under these terms.
628 | 
629 |   To do so, attach the following notices to the program.  It is safest
630 | to attach them to the start of each source file to most effectively
631 | state the exclusion of warranty; and each file should have at least
632 | the "copyright" line and a pointer to where the full notice is found.
633 | 
634 |     {one line to give the program's name and a brief idea of what it does.}
635 |     Copyright (C) 2018  {name of author}
636 | 
637 |     This program is free software: you can redistribute it and/or modify
638 |     it under the terms of the GNU General Public License as published by
639 |     the Free Software Foundation, either version 3 of the License, or
640 |     (at your option) any later version.
641 | 
642 |     This program is distributed in the hope that it will be useful,
643 |     but WITHOUT ANY WARRANTY; without even the implied warranty of
644 |     MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
645 |     GNU General Public License for more details.
646 | 
647 |     You should have received a copy of the GNU General Public License
648 |     along with this program.  If not, see <http://www.gnu.org/licenses/>.
649 | 
650 | Also add information on how to contact you by electronic and paper mail.
651 | 
652 |   If the program does terminal interaction, make it output a short
653 | notice like this when it starts in an interactive mode:
654 | 
655 |     emlrender  Copyright (C) 2018  Xavier Mertens
656 |     This program comes with ABSOLUTELY NO WARRANTY; for details type `show w'.
657 |     This is free software, and you are welcome to redistribute it
658 |     under certain conditions; type `show c' for details.
659 | 
660 | The hypothetical commands `show w' and `show c' should show the appropriate
661 | parts of the General Public License.  Of course, your program's commands
662 | might be different; for a GUI interface, you would use an "about box".
663 | 
664 |   You should also get your employer (if you work as a programmer) or school,
665 | if any, to sign a "copyright disclaimer" for the program, if necessary.
666 | For more information on this, and how to apply and follow the GNU GPL, see
667 | <http://www.gnu.org/licenses/>.
668 | 
669 |   The GNU General Public License does not permit incorporating your program
670 | into proprietary programs.  If your program is a subroutine library, you
671 | may consider it more useful to permit linking proprietary applications with
672 | the library.  If this is what you want to do, use the GNU Lesser General
673 | Public License instead of this License.  But first, please read
674 | <http://www.gnu.org/philosophy/why-not-lgpl.html>.


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