handle missing certificate file

[lets-encrypt-tiny.git] / letsencrypt-tiny

diff --git a/letsencrypt-tiny b/letsencrypt-tiny
index 87fcd41026b1394cd05816d67af18fa910d39e39..6df989b772fa52439947d3a95650e41f6cb0f82e 100755 (executable)
--- a/letsencrypt-tiny
+++ b/letsencrypt-tiny
@@ -1,5 +1,5 @@
 #!/usr/bin/env python3
 #!/usr/bin/env python3

-## Call with "--help" for documentation.
+## See <https://www.ralfj.de/blog/2017/12/26/lets-encrypt.html> for documentation.

 
 import argparse, configparser, itertools, stat, os, os.path, sys, subprocess, datetime
 
 
 import argparse, configparser, itertools, stat, os, os.path, sys, subprocess, datetime
 


@@ -11,18 +11,14 @@ def readConfig(fname, defSection = 'DEFAULT'):
         config.read_file(stream)
     return config
 
         config.read_file(stream)
     return config
 

-def certfile(name, suff = None):
+def certfile(name):

     global config
     global config

-    return os.path.join(config['dirs']['certs'], name + ".crt" + ('' if suff is None else '+'+suff) )
+    return os.path.join(config['dirs']['certs'], name + ".crt" )

 
 def keyfile(name):
     global config
     return os.path.join(config['dirs']['keys'], name + ".key")
 
 
 def keyfile(name):
     global config
     return os.path.join(config['dirs']['keys'], name + ".key")
 

-def csrfile(name):
-    global config
-    return os.path.join(config['dirs']['csrs'], name + ".csr")
-

 def make_backup(fname):
     if os.path.exists(fname):
         backupname = os.path.basename(fname) + "." + str(datetime.date.today())
 def make_backup(fname):
     if os.path.exists(fname):
         backupname = os.path.basename(fname) + "." + str(datetime.date.today())


@@ -30,7 +26,7 @@ def make_backup(fname):
         while True:
             backupfile = os.path.join(config['dirs']['backups'], backupname + "." + str(i))
             if not os.path.exists(backupfile):
         while True:
             backupfile = os.path.join(config['dirs']['backups'], backupname + "." + str(i))
             if not os.path.exists(backupfile):

-                os.rename(src = fname, dst = backupfile)
+                os.rename(fname, backupfile)

                 break
             elif i >= 100:
                 print("Somehow it's really hard to find a name for the backup file...")
                 break
             elif i >= 100:
                 print("Somehow it's really hard to find a name for the backup file...")


@@ -39,7 +35,7 @@ def make_backup(fname):
 
 def trigger_hook(hook):
     global config
 
 def trigger_hook(hook):
     global config

-    exe = config['hooks'][hook]
+    exe = config['hooks'].get(hook)

     if exe is not None:
         subprocess.check_call([exe])
 
     if exe is not None:
         subprocess.check_call([exe])
 


@@ -50,96 +46,98 @@ def cert_expiry(name):
     from certcheck import cert_expiry_date
     return cert_expiry_date(certfile(name))
 
     from certcheck import cert_expiry_date
     return cert_expiry_date(certfile(name))
 

+## Work functions, operating on file names
+

 ## The interesting work
 ## The interesting work

-def acme(name, domains):
+def acme(keyfilename, certfilename, domains):

     global config
     global config

+    accountkey = config['acme']['account-key']
+    csrfilename = certfilename + '.csr.tmp'
+    assert os.path.exists(keyfilename)
+    assert accountkey

     # Generating the CSR is done by a shell script
     exe = os.path.join(os.path.dirname(__file__), 'gencsr')
     # Generating the CSR is done by a shell script
     exe = os.path.join(os.path.dirname(__file__), 'gencsr')

-    csr = subprocess.check_output([exe, keyfile(name)] + domains)
-    with open(csrfile(name), 'wb') as file:
+    csr = subprocess.check_output([exe, keyfilename] + domains)
+    assert not os.path.exists(csrfilename), "The temporary CSR file {} still exists. It seems something went wrong on a previous request. You may want to remove the file manually.".format(csrfilename)
+    with open(csrfilename, 'wb') as file:

         file.write(csr)
         file.write(csr)

-    # call acme-tiny as a script
-    acme_tiny = os.path.join(config['acme']['acme-tiny'], 'acme_tiny.py')
-    signed_crt = subprocess.check_output(["python", acme_tiny, "--quiet", "--account-key", config['acme']['account-key'], "--csr", csrfile(name), "--acme-dir", config['acme']['challenge-dir']])
-    # save new certificate
-    make_backup(certfile(name))
-    with open(certfile(name), 'wb') as f:
-        f.write(signed_crt)
-    # append DH params
-    dhfile = config['DEFAULT'].get('dh-params')
-    if dhfile is not None:
-        with open(dhfile, 'rb') as f:
-            dh = f.read()
-        with open(certfile(name, 'dh'), 'wb') as f:
+    try:
+        # call acme-tiny as a script
+        acme_tiny = os.path.join(os.path.dirname(os.path.realpath(__file__)), 'acme-tiny', 'acme_tiny.py')
+        signed_crt = subprocess.check_output(["python", acme_tiny, "--quiet", "--account-key", accountkey, "--csr", csrfilename, "--acme-dir", config['acme']['challenge-dir']])
+        # save new certificate
+        make_backup(certfilename)
+        with open(certfilename, 'wb') as f:

             f.write(signed_crt)
             f.write(signed_crt)

-            f.write(dh)
+    finally:
+        # clean up
+        os.remove(csrfilename)
+
+def openssl_genrsa(keyfilename):
+    with subprocess.Popen(["openssl", "genrsa", str(int(config['DEFAULT']['key-length']))], stdout=subprocess.PIPE, stderr=subprocess.PIPE) as f:
+        (stdout, stderr) = f.communicate()
+        if f.returncode:
+            sys.stderr.write(stderr)
+            raise Exception("Error while generating private key")
+    # Now we have a key, save it. This should never overwrite anything.
+    assert not os.path.exists(keyfilename)
+    with open(keyfilename, 'wb') as f:
+        f.write(stdout)

 
 

+## High-level functions, operating on nice key names

 def request_cert(name):
     global config
     if not os.path.exists(keyfile(name)):
         raise Exception("No such key: {}".format(name))
     domains = config['DEFAULT']['domains'].split()
 def request_cert(name):
     global config
     if not os.path.exists(keyfile(name)):
         raise Exception("No such key: {}".format(name))
     domains = config['DEFAULT']['domains'].split()

-    print("Obtaining certificate '{}' for domains {}".format(name, ' '.join(domains)))
-    acme(name, domains)
+    print("Obtaining certificate '{}' for domains: {}".format(name, ' '.join(domains)))
+    acme(keyfile(name), certfile(name), domains)

 
 def generate_key(name):
 
 def generate_key(name):

+    assert not os.path.exists(certfile(name)), "Don't make create a new key for an old cert"

     print("Generating new private key '{}'".format(name))
     print("Generating new private key '{}'".format(name))

-    with subprocess.Popen(["openssl", "genrsa", str(int(config['DEFAULT']['key-length']))], stdout=subprocess.PIPE, stderr=subprocess.PIPE) as f:
-        (stdout, stderr) = f.communicate()
-        if f.returncode:
-            sys.stderr.write(stderr)
-            raise Exception("Error while generating private key")
-    # now we have a key, save it
-    make_backup(keyfile(name))
-    with open(keyfile(name), 'wb') as f:
-        f.write(stdout)
+    openssl_genrsa(keyfile(name))

 
 

-def check_staging():
+def check_staging(live, staging):

     '''Returns 0 if nothing was done, 1 if a stage key is present but has to be kept, 2 is a stage key was unstaged.'''
     '''Returns 0 if nothing was done, 1 if a stage key is present but has to be kept, 2 is a stage key was unstaged.'''

-    live = config['files']['live']
-    staging = config['files'].get('staging')
-    if staging is None or not os.path.exists(keyfile(staging)):
+    if not os.path.exists(keyfile(staging)):

         return 0
     
         return 0
     

-    staging_time = datetime.timedelta(hours = int(config['timing']['staging-hours']))
+    staging_time = datetime.timedelta(hours = int(config['timing'].get('staging-hours', 0)))

     key_age = datetime.datetime.now() - key_mtime(staging)
     if key_age < staging_time:
         return 1
     print("Unstaging '{}' to '{}'".format(staging, live))
     # unstage the key!
     make_backup(keyfile(live))
     key_age = datetime.datetime.now() - key_mtime(staging)
     if key_age < staging_time:
         return 1
     print("Unstaging '{}' to '{}'".format(staging, live))
     # unstage the key!
     make_backup(keyfile(live))

-    os.rename(src = keyfile(staging), dst = keyfile(live))
+    os.rename(keyfile(staging), keyfile(live))

     make_backup(certfile(live))
     make_backup(certfile(live))

-    os.rename(src = certfile(staging), dst = certfile(live))
-    try:
-        os.rename(src = certfile(staging, 'dh'), dst = certfile(live, 'dh'))
-    except FileNotFoundError:
-        pass
+    os.rename(certfile(staging), certfile(live))

     return 2
 
     return 2
 

-def auto_renewal():
+def auto_renewal(live, staging):

     '''Returns 0 if nothing was done, 1 if only certs were changed, 2 if certs and keys were changed.'''
     '''Returns 0 if nothing was done, 1 if only certs were changed, 2 if certs and keys were changed.'''

-    live = config['files']['live']
-    staging = config['files'].get('staging')
-    

     max_key_age = datetime.timedelta(days = int(config['timing']['max-key-age-days']))
     renew_cert_time = datetime.timedelta(days = int(config['timing']['renew-cert-before-expiry-days']))
     
     # determine what to do
     now = datetime.datetime.now()
     key_age = now - key_mtime(live)
     max_key_age = datetime.timedelta(days = int(config['timing']['max-key-age-days']))
     renew_cert_time = datetime.timedelta(days = int(config['timing']['renew-cert-before-expiry-days']))
     
     # determine what to do
     now = datetime.datetime.now()
     key_age = now - key_mtime(live)

-    cert_validity = cert_expiry(live) - now

     need_new_key = key_age >= max_key_age
     need_new_key = key_age >= max_key_age

-    need_new_cert = cert_validity <= renew_cert_time
+    if os.path.exists(live):
+        cert_validity = cert_expiry(live) - now
+        need_new_cert = cert_validity <= renew_cert_time
+    else:
+        need_new_cert = True

     if need_new_cert and key_age + renew_cert_time >= max_key_age:
         # We are about to request a new certificate, and within <renew_cert_time>, we need a new key: Get the new key now
         need_new_key = True
     
     # Do it
     if need_new_key:
     if need_new_cert and key_age + renew_cert_time >= max_key_age:
         # We are about to request a new certificate, and within <renew_cert_time>, we need a new key: Get the new key now
         need_new_key = True
     
     # Do it
     if need_new_key:

-        new_key_name = (live if staging is None else staging)
-        generate_key(new_key_name)
-        request_cert(new_key_name)
+        generate_key(staging)
+        request_cert(staging)
+        check_staging(live, staging) # we may want to immediately enable the new key & cert

         return 2
     elif need_new_cert:
         request_cert(live)
         return 2
     elif need_new_cert:
         request_cert(live)


@@ -161,34 +159,33 @@ if __name__ == "__main__":
                         help="The action to perform. Possible values: init, renew, cron")
     args = parser.parse_args()
     
                         help="The action to perform. Possible values: init, renew, cron")
     args = parser.parse_args()
     

-    # read config
+    # read config, sanity check

     if not os.path.isfile(args.config):
         raise Exception("The config file does not exist: "+args.config)
     global config
     config = readConfig(args.config)
     
     if not os.path.isfile(args.config):
         raise Exception("The config file does not exist: "+args.config)
     global config
     config = readConfig(args.config)
     

+    live = config['files']['live']
+    staging = config['files']['staging']

     if args.action[0] == 'renew':
     if args.action[0] == 'renew':

-        live = config['files']['live']
-        staging = config['files'].get('staging')
-        

         request_cert(live)
         request_cert(live)

-        if staging is not None and os.path.exists(keyfile(staging)):
+        if os.path.exists(keyfile(staging)) and os.path.exists(certfile(staging)):

             request_cert(staging)
         # trigger the "new cert" hook
         if args.hooks:
             trigger_hook('post-certchange')
     elif args.action[0] == 'cron':
         # First, check if we need to unstage a staging key
             request_cert(staging)
         # trigger the "new cert" hook
         if args.hooks:
             trigger_hook('post-certchange')
     elif args.action[0] == 'cron':
         # First, check if we need to unstage a staging key

-        unstaged = check_staging()
+        unstaged = check_staging(live, staging)

         if unstaged >= 1:
         if unstaged >= 1:

-            # A staging eky is present, do *not* check for renewal
+            # A staging key is present, do *not* check for renewal

             if unstaged >= 2 and args.hooks:
                 # trigger all the hooks
                 trigger_hook('post-certchange')
                 trigger_hook('post-keychange')
         else:
             # Check if we need to renew anything
             if unstaged >= 2 and args.hooks:
                 # trigger all the hooks
                 trigger_hook('post-certchange')
                 trigger_hook('post-keychange')
         else:
             # Check if we need to renew anything

-            renewed = auto_renewal()
+            renewed = auto_renewal(live, staging)

             if args.hooks:
                 if renewed >= 1:
                     trigger_hook('post-certchange')
             if args.hooks:
                 if renewed >= 1:
                     trigger_hook('post-certchange')


@@ -199,14 +196,19 @@ if __name__ == "__main__":
         try:
             os.makedirs(config['dirs']['certs'], mode = 0o755, exist_ok = True)
             os.makedirs(config['dirs']['keys'], mode = 0o710, exist_ok = True)
         try:
             os.makedirs(config['dirs']['certs'], mode = 0o755, exist_ok = True)
             os.makedirs(config['dirs']['keys'], mode = 0o710, exist_ok = True)

-            os.makedirs(config['dirs']['csrs'], mode = 0o755, exist_ok = True)

             os.makedirs(config['dirs']['backups'], mode = 0o700, exist_ok = True)
         except OSError:
             pass
             os.makedirs(config['dirs']['backups'], mode = 0o700, exist_ok = True)
         except OSError:
             pass

+        # if necessary, generate ACME account key
+        accountkey = config['acme']['account-key']
+        if not os.path.exists(accountkey):
+            print("Generating new ACME key")
+            openssl_genrsa(accountkey)

         # if necessary, generate key + certificate
         live = config['files']['live']
         if not os.path.exists(keyfile(live)):
             generate_key(live)
         # if necessary, generate key + certificate
         live = config['files']['live']
         if not os.path.exists(keyfile(live)):
             generate_key(live)

+        if not os.path.exists(certfile(live)):

             request_cert(live)
             if args.hooks:
                 trigger_hook('post-certchange')
             request_cert(live)
             if args.hooks:
                 trigger_hook('post-certchange')