Improve display of help and list certificate.

README.md

@@ -2,43 +2,67 @@
 
 I wanted to install a certificate generated by Let's encrypt on my brand new laser printer 
 (HP Laserjet MFJ 4302) for the integrated administration webserver.
-After research on the web, I discovered 
+After research on the web, I discovered that although there were projects supporting older models
+nothing was existing for newer models.
+Hence I decided to write my own tool in Python.
+It was designed by reverse engineering the integrated administration webserver following the
+network exchange when using the menu dedicated to certificate management 
+(Security -> Certicates management)
 
-# Arguments
+# Command
 
-positional arguments:
+```bash
-  {csr,pem}             command help
+  {list, del, csr,pem}
-    csr                 Create CSR
+    list                List certificates known by the printer
-    pem                 Install certificate
+    del                 Delete a certificate
-
+    csr                 Create a certificate signing request (CSR)
-options:
+    pem                 Install a PEM certificate
-  -h, --help            show this help message and exit
-  -d, --debug           Activate debug.
-  -c, --config CONFIG_FILENAME
-                        Configuration file.
-  -u, --user USERNAME   Username.
-  -p, --password [PASSWORD]
-                        Password.
-  -H, --host HOSTNAME   Hostname.
-  -n, --no-tls-verification
-                        Verify certificate validity.
 
+Common options:
+  -h, --help                        Show this help message and exit
+  -d, --debug                       Activate debug.
+  -c, --config CONFIG_FILENAME      Configuration file.
+  -u, --user USERNAME               Username (admin).
+  -p, --password [PASSWORD]         Specify admin password.
+  -H, --host HOSTNAME               Hostname.
+  -n, --no-tls-verification         Do not verify certificate validity.
+```
 
 # How to use it ?
 
-To obtain a CSR:
+After playing a lot with the administration web server, I discover a reproducible way to convince
-```
+the printer to accept a Let's Encrypt certificate.
+First you need to ask a CSR generated by the printer:
+```bash
 ./refresh-certificate.py  -c ./config.ini -n -p PASSWORD csr
 ```
+This way the private key part of the certificate is only known by the printer.
+I was not able to import the private key of a Let's Encrypt certificate as obtained when generating
+the certificate directly from ACME.
 
-To obtain a PEM certificate from Let's encrypt:
+Next you need to ask Let's Encrypt to sign the CSR:
 ```
 certbot certonly --webroot -w /var/www/letsencrypt/ --csr printer.csr
 ```
 
-To install the PEM file on the printer:
+You should obtain three PEM files in response:
+
+1. _cert.pem_: the certificate itself (PEM format)
+2. _chain.pem_: the intermediate CA that signed the certificate (PEM format)
+3. _fullchain.pem_: the two previous files concatenated.
+
+Finally you can install the certificate PEM file on the printer:
 ```
-./refresh-certificate.py  -c ./config.ini -n -p PASSWORD pem 
+./refresh-certificate.py  -c ./config.ini -n -p PASSWORD pem -i fullchain.pem
 ```
 
+Please note that during the last step, you can add either the _cert.pem_ file or 
+the _fullchain.pem_ files. In both cases, you should be able to connect to the printer webserver
+without warning message from your navigator (tested on Firefox and Chromium).
+This is possible because the main navigators comes with a certificates store that contains
+not only the root certificate of Let's Encrypt but also the intermediate certificates.
+However, note that most others tools will fail to connect to the Web server of the printer
+(including this tool) because the printer will only present the final certificate.
+You really have to install the _fullchain.pem_ to remove TLS connexion errors from all tools.
+
 

refresh-certificate.py

@@ -39,11 +39,15 @@ import random
 import base64
 from cryptography import x509
 from cryptography.hazmat.primitives.serialization import Encoding
+from dateutil.parser import parse
+from typeguard import typechecked
+from datetime import datetime, timedelta
 
 import requests
 import coloredlogs
 
-def create_nonce(length: int=45):
+@typechecked
+def create_nonce(length: int=45) -> str:
     """
     Generate a random nonce string.
 
@@ -72,7 +76,9 @@ def create_nonce(length: int=45):
 
     return nonce
 
-def get_bearer(hostname: str, verify: bool, username: str, password:str):
+
+@typechecked
+def get_bearer(hostname: str, verify: bool, username: str, password:str) -> str:
     """
     Retrieve an OAuth bearer token for authentication with a HP CDM server.
 
@@ -170,8 +176,10 @@ def get_bearer(hostname: str, verify: bool, username: str, password:str):
 
     return bearer
 
+
+@typechecked
 def get_csr(hostname: str, verify: bool, username: str, password: str, ou: str, org: str, city:str,
-            state: str, country: str, filename: str):
+            state: str, country: str, filename: str) -> None:
     """
     Generate a Certificate Signing Request (CSR) for a HP CDM server.
 
@@ -252,12 +260,16 @@ def get_csr(hostname: str, verify: bool, username: str, password: str, ou: str,
             finished = True
 
     csr = csr['certificateData']
-    print(csr)
+
+    logger.debug('CSR:\n %s', csr)
 
     with open(filename, 'w+', encoding='utf-8') as f:
         f.write(csr)
 
-def install_certificate(hostname, verify, username, password, filename, bearer=None):
+
+@typechecked
+def install_certificate(hostname: str, verify: bool, username: str, password: str, filename:str,
+                        bearer=None) -> None:
     """
     Install a certificate on a HP CDM server.
 
@@ -333,7 +345,44 @@ def install_certificate(hostname, verify, username, password, filename, bearer=N
 
             logger.info('Certificate successfully installed.')
 
-def get_certificates(hostname, verify, username, password, bearer=None):
+@typechecked
+def self_signed(hostname:str, verify:bool, username: str, password: str, bearer=None) -> None:
+    logger = logging.getLogger(__name__)
+    base_url = f'https://{hostname}'
+
+    if bearer is None:
+        bearer = get_bearer(hostname, verify, username, password)
+
+
+    now = datetime.now()
+    end = now + timedelta(days=365)
+    end = end.strftime('%Y-%m-%dT%H:%M:%S.000Z')
+    url = base_url+'/cdm/certificate/v1/certificates/selfSignedCertificate'
+    certificate = {"version":"1.1.0","signatureAlgorithm":"sha256WithRsa",
+                   "subjectAlternativeNameList":[hostname], "privateKeyExportable": False,
+                   "links":[{"rel":"certificateConstraints",
+                    "href":"/cdm/certificate/v1/certificates/selfSignedCertificate/constraints",
+                    "hints":None}],
+                   "certificateAttributes":{"commonName":hostname},
+                   "keyInfo":{"keyType":"rsa","keyStrength":"bits2048"},
+                   "validity":{"toDate":end},"state":"processing"}
+
+    headers = { 'Authorization': f'Bearer {bearer}' }
+
+    r = requests.patch(url, headers=headers, data=json.dumps(certificate), verify=verify,
+                              timeout=10)
+
+    if r.status_code != 204:
+        logger.error('Impossible to create a self-signed certificate. Error code: %d',
+                     r.status_code)
+        sys.exit(-1)
+
+    logger.info('Self-signed certificate created successfully.')
+
+
+@typechecked
+def get_certificates(hostname:str, verify:bool, username: str, password: str,
+                     bearer=None) -> dict[int, dict]:
     """
     Retrieve a list of certificates from an HP CDM server.
 
@@ -386,6 +435,8 @@ def get_certificates(hostname, verify, username, password, bearer=None):
 
     return res
 
+
+@typechecked
 def delete_certificate(hostname, verify, username, password, certificates, certid, bearer=None):
     """
     Delete a certificate from an HP CDM server.
@@ -430,6 +481,8 @@ def delete_certificate(hostname, verify, username, password, certificates, certi
         logger.error('Impossible to delete certificate')
         sys.exit(-1)
 
+    logger.info('Certificate deleted with success.')
+
 def main():
     """
     Main entry point of the program.
@@ -478,13 +531,15 @@ def main():
 
     subparsers = parser.add_subparsers(dest='command', required=True, help='command help')
 
-    subparsers.add_parser('list', help='List certificates')
+    subparsers.add_parser('list', help='List certificates.')
 
-    parser_delete = subparsers.add_parser('del', help='Delete a certificate')
+    subparsers.add_parser('self', help='Create a self-signed certificate.')
+
+    parser_delete = subparsers.add_parser('del', help='Delete a certificate.')
     parser_delete.add_argument("-#", "--number", dest='certid', required=True, type=int,
                         help="Certificate number as given by list command.")
 
-    parser_create_csr = subparsers.add_parser('csr', help='Create CSR')
+    parser_create_csr = subparsers.add_parser('csr', help='Create a certificate signing request.')
     parser_create_csr.add_argument("-C", "--country", dest='country', required=False, default='US',
                                  help="Country.")
     parser_create_csr.add_argument("-s", "--state", dest='state', required=False, help="State.")
@@ -496,7 +551,7 @@ def main():
     parser_create_csr.add_argument("-o", "--output", dest='output', required=False, default=None,
                                  help="Output file.")
 
-    parser_install_certificate = subparsers.add_parser('pem', help='Install certificate')
+    parser_install_certificate = subparsers.add_parser('pem', help='Install a certificate.')
     parser_install_certificate.add_argument("-i", "--input", dest='input', required=True,
                                            default=None, help="Input file.")
 
@@ -579,10 +634,14 @@ def main():
             certs = get_certificates(hostname=args.hostname, verify=args.verify,
                                      username=args.username,
                                      password=args.password)
+            logger.info('List of certificates:')
             for certid, cert in certs.items():
                 subject = cert.get('subject')
                 issuer = cert.get('issuer')
-                print(f'{certid} - {subject} issued by {issuer}.')
+                validity = cert.get('validity')
+                begin = parse(validity.get('fromDate')).strftime('%Y-%m-%d (%H:%M)')
+                end = parse(validity.get('toDate')).strftime('%Y-%m-%d (%H:%M)')
+                print(f'{certid} - {subject} issued by {issuer}. From: {begin} to {end}')
         case 'del':
             bearer = get_bearer(hostname=args.hostname, verify=args.verify, username=args.username,
                                 password=args.password)
@@ -602,6 +661,9 @@ def main():
         case 'pem':
             install_certificate(hostname=args.hostname, verify=args.verify, username=args.username,
                                 password=args.password, filename=args.input)
+        case 'self':
+            self_signed(hostname=args.hostname, verify=args.verify, username=args.username,
+                        password=args.password)
         case _:
             logger.error('Unknown command: %s', args.command)
             sys.exit(-1)

requirements.txt

@@ -1,3 +1,5 @@
 requests
 coloredlogs
 cryptography
+typeguard
+dateutils