vulpicastor · April 26, 2017 01:32 · Apr 26, 2017 · Oct 14, 2016 · Oct 14, 2016 · Jul 17, 2016
diff --git a/dnscheck.py b/dnscheck.py
@@ -99,7 +99,7 @@ def main():
             wait = DEFAULT_INTERVAL
             timeout = 0
             time.sleep(wait)
-        except dns.exception.Timeout:
+        except dns.exception.Timeout as err:
             zwrite.zwrite(str(err) + "\nRetry in {} seconds".format(wait), zsig=domain, **DEFAULT_ARGS)
             wait = randrange(0, BACKOFF_START * 2**timeout)
             timeout += 1

diff --git a/dnscheck.py b/dnscheck.py
@@ -7,9 +7,9 @@
 from random import randrange
 import zwrite
 
-DEFAULT_ARGS = {"classname": "slz-auto",
+DEFAULT_ARGS = {"classname": "test",
                 "instance": "dns",
-                "sender": "slz_bot",
+                "sender": "dns_bot",
                 "opcode": "auto"}
 
 TEMPLATE = "{:15} SOA Serial: @b({})"

diff --git a/dnscheck.py b/dnscheck.py
@@ -4,15 +4,19 @@
 import sys
 import time
 import dns.resolver, dns.exception
+from random import randrange
 import zwrite
 
-DEFAULT_ARGS = {"classname": "test",
+DEFAULT_ARGS = {"classname": "slz-auto",
                 "instance": "dns",
-                "sender": "bot",
+                "sender": "slz_bot",
                 "opcode": "auto"}
 
 TEMPLATE = "{:15} SOA Serial: @b({})"
 
+DEFAULT_INTERVAL = 300
+BACKOFF_START = 10
+
 def find_nameservers(domain):
     nameservers = []
     try:
@@ -75,20 +79,31 @@ def main():
     try:
         resolver_ips = find_ips(find_nameservers(domain))
     except (dns.exception.Timeout, dns.resolver.NXDOMAIN, dns.resolver.YXDOMAIN,
-            dns.resolver.NoAnswer, dns.resolver.NoNameservers):
+            dns.resolver.NoAnswer, dns.resolver.NoNameservers) as err:
         if len(sys.argv) > 2:
             resolver_ips = sys.argv[2:]
         else:
+            zwrite.zwrite(str(err), zsig=domain, **DEFAULT_ARGS)
             raise
     resolvers = spawn_resolvers(resolver_ips)
     serials = {}
     for r in resolvers:
         serials[r.nameservers[0]] = "0"
+    wait = DEFAULT_INTERVAL
+    timeout = 0
     while True:
-        message = check_soa_serial(domain, resolvers, serials)
-        if message:
-            zwrite.zwrite(message, zsig=domain, **DEFAULT_ARGS)
-        time.sleep(300)
+        try:
+            message = check_soa_serial(domain, resolvers, serials)
+            if message:
+                zwrite.zwrite(message, zsig=domain, **DEFAULT_ARGS)
+            wait = DEFAULT_INTERVAL
+            timeout = 0
+            time.sleep(wait)
+        except dns.exception.Timeout:
+            zwrite.zwrite(str(err) + "\nRetry in {} seconds".format(wait), zsig=domain, **DEFAULT_ARGS)
+            wait = randrange(0, BACKOFF_START * 2**timeout)
+            timeout += 1
+            time.sleep(wait)
 
 if __name__ == "__main__":
     main()
diff --git a/dnscheck.py b/dnscheck.py
@@ -91,4 +91,4 @@ def main():
         time.sleep(300)
 
 if __name__ == "__main__":
-    main()
+    main()
diff --git a/dnscheck.py b/dnscheck.py
@@ -6,9 +6,9 @@
 import dns.resolver, dns.exception
 import zwrite
 
-DEFAULT_ARGS = {"classname": "slz-auto",
+DEFAULT_ARGS = {"classname": "test",
                 "instance": "dns",
-                "sender": "slz_bot",
+                "sender": "bot",
                 "opcode": "auto"}
 
 TEMPLATE = "{:15} SOA Serial: @b({})"

diff --git a/dnscheck.py b/dnscheck.py
@@ -3,22 +3,26 @@
 from __future__ import print_function
 import sys
 import time
-import dns.resolver
+import dns.resolver, dns.exception
 import zwrite
 
-DEFAULT_ARGS = {"classname": "test",
+DEFAULT_ARGS = {"classname": "slz-auto",
                 "instance": "dns",
-                "sender": "bot",
+                "sender": "slz_bot",
                 "opcode": "auto"}
 
 TEMPLATE = "{:15} SOA Serial: @b({})"
 
 def find_nameservers(domain):
     nameservers = []
-    answer = dns.resolver.query(domain, "NS")
-    for ns in answer:
-        nameservers.append(ns.target)
-    return nameservers
+    try:
+        answer = dns.resolver.query(domain, "NS")
+        for ns in answer:
+            nameservers.append(ns.target)
+        return nameservers
+    except dns.resolver.NoNameservers:
+        print("Error: Cannot find name servers for {}.".format(domain))
+        raise
 
 def find_ips(domains):
     ips = []
@@ -28,7 +32,6 @@ def find_ips(domains):
             ips.append(a.address)
     return ips
 
-
 def spawn_resolvers(nameservers):
     resolvers = []
     for ns in nameservers:
@@ -48,25 +51,36 @@ def check_soa_serial(domain, resolvers, serials):
     new_serials = {}
     updated = False
     for r in resolvers:
-        soa = r.query(domain, "SOA")
         n = r.nameservers[0]
-        s = soa[0].serial
-        if serials_gt(s, serials[n]):
-            answers.append(TEMPLATE.format(n, s) + " @b(@color(green)UPDATE)")
-            updated = True
-        elif serials_eq(s, serials[n]):
-            if updated:
-                answers.append(TEMPLATE.format(n, s) + " @b(@color(yellow)UNCHANGED)")
-        else:
-            answers.append(TEMPLATE.format(n, s) + " @b(@color(red)REGRESSION)")
-            updated = True
-        new_serials[n] = s
+        try:
+            soa = r.query(domain, "SOA")
+            s = soa[0].serial
+            if serials_gt(s, serials[n]):
+                answers.append(TEMPLATE.format(n, s) + " @b(@color(green)UPDATE)")
+                updated = True
+            elif serials_eq(s, serials[n]):
+                if updated:
+                    answers.append(TEMPLATE.format(n, s) + " @b(@color(yellow)UNCHANGED)")
+            else:
+                answers.append(TEMPLATE.format(n, s) + " @b(@color(red)REGRESSION)")
+                updated = True
+            new_serials[n] = s
+        except dns.resolver.NoNameservers:
+            answers.append(TEMPLATE.format(n, "@color(red)UNKNOWN"))
     serials.update(new_serials)
     return "\n".join(answers)
 
 def main():
     domain = sys.argv[1]
-    resolvers = spawn_resolvers(find_ips(find_nameservers(domain)))
+    try:
+        resolver_ips = find_ips(find_nameservers(domain))
+    except (dns.exception.Timeout, dns.resolver.NXDOMAIN, dns.resolver.YXDOMAIN,
+            dns.resolver.NoAnswer, dns.resolver.NoNameservers):
+        if len(sys.argv) > 2:
+            resolver_ips = sys.argv[2:]
+        else:
+            raise
+    resolvers = spawn_resolvers(resolver_ips)
     serials = {}
     for r in resolvers:
         serials[r.nameservers[0]] = "0"
@@ -77,4 +91,4 @@ def main():
         time.sleep(300)
 
 if __name__ == "__main__":
-    main()
+    main()
diff --git a/dnscheck.py b/dnscheck.py
@@ -6,9 +6,9 @@
 import dns.resolver
 import zwrite
 
-DEFAULT_ARGS = {"classname": "slz-auto",
+DEFAULT_ARGS = {"classname": "test",
                 "instance": "dns",
-                "sender": "slz_bot",
+                "sender": "bot",
                 "opcode": "auto"}
 
 TEMPLATE = "{:15} SOA Serial: @b({})"

diff --git a/dnscheck.py b/dnscheck.py
@@ -6,22 +6,29 @@
 import dns.resolver
 import zwrite
 
-DEFAULT_ARGS = {"classname": "message",
+DEFAULT_ARGS = {"classname": "slz-auto",
                 "instance": "dns",
-                "sender": "bot",
-                "zsig": "dnscheck.py",
+                "sender": "slz_bot",
                 "opcode": "auto"}
 
 TEMPLATE = "{:15} SOA Serial: @b({})"
 
 def find_nameservers(domain):
     nameservers = []
-    ns = dns.resolver.query(domain, "NS")
-    for rrset in ns.response.additional:
-        for a in rrset:
-            nameservers.append(a.address)
+    answer = dns.resolver.query(domain, "NS")
+    for ns in answer:
+        nameservers.append(ns.target)
     return nameservers
 
+def find_ips(domains):
+    ips = []
+    for d in domains:
+        answer = dns.resolver.query(d)
+        for a in answer:
+            ips.append(a.address)
+    return ips
+
+
 def spawn_resolvers(nameservers):
     resolvers = []
     for ns in nameservers:
@@ -59,15 +66,14 @@ def check_soa_serial(domain, resolvers, serials):
 
 def main():
     domain = sys.argv[1]
-    print(domain)
-    resolvers = spawn_resolvers(find_nameservers(domain))
+    resolvers = spawn_resolvers(find_ips(find_nameservers(domain)))
     serials = {}
     for r in resolvers:
         serials[r.nameservers[0]] = "0"
     while True:
         message = check_soa_serial(domain, resolvers, serials)
         if message:
-            zwrite.zwrite("\n".join((domain, message)), **DEFAULT_ARGS)
+            zwrite.zwrite(message, zsig=domain, **DEFAULT_ARGS)
         time.sleep(300)
 
 if __name__ == "__main__":

diff --git a/dnscheck.py b/dnscheck.py
@@ -37,7 +37,7 @@ def serials_eq(a, b):
     return int(a) == int(b)
 
 def check_soa_serial(domain, resolvers, serials):
-    answers = [domain]
+    answers = []
     new_serials = {}
     updated = False
     for r in resolvers:
@@ -67,7 +67,7 @@ def main():
     while True:
         message = check_soa_serial(domain, resolvers, serials)
         if message:
-            zwrite.zwrite(message, **DEFAULT_ARGS)
+            zwrite.zwrite("\n".join((domain, message)), **DEFAULT_ARGS)
         time.sleep(300)
 
 if __name__ == "__main__":

diff --git a/dnscheck.py b/dnscheck.py
@@ -71,4 +71,4 @@ def main():
         time.sleep(300)
 
 if __name__ == "__main__":
-    main()
+    main()
diff --git a/dnscheck.py b/dnscheck.py
@@ -47,10 +47,11 @@ def check_soa_serial(domain, resolvers, serials):
         if serials_gt(s, serials[n]):
             answers.append(TEMPLATE.format(n, s) + " @b(@color(green)UPDATE)")
             updated = True
-        elif serials_eq(s, serials[n]) and updated:
-            answers.append(TEMPLATE.format(n, s) + " @b(@color(yellow)UNCHANGED)")
+        elif serials_eq(s, serials[n]):
+            if updated:
+                answers.append(TEMPLATE.format(n, s) + " @b(@color(yellow)UNCHANGED)")
         else:
-            answers.append(TEMPLATE.format(n, s) + " @b(@color(yellow)REGRESSION)")
+            answers.append(TEMPLATE.format(n, s) + " @b(@color(red)REGRESSION)")
             updated = True
         new_serials[n] = s
     serials.update(new_serials)

diff --git a/dnscheck.py b/dnscheck.py
@@ -52,6 +52,8 @@ def check_soa_serial(domain, resolvers, serials):
         else:
             answers.append(TEMPLATE.format(n, s) + " @b(@color(yellow)REGRESSION)")
             updated = True
+        new_serials[n] = s
+    serials.update(new_serials)
     return "\n".join(answers)
 
 def main():

diff --git a/dnscheck.py b/dnscheck.py
@@ -0,0 +1,71 @@
+#!/usr/bin/env python3
+
+from __future__ import print_function
+import sys
+import time
+import dns.resolver
+import zwrite
+
+DEFAULT_ARGS = {"classname": "message",
+                "instance": "dns",
+                "sender": "bot",
+                "zsig": "dnscheck.py",
+                "opcode": "auto"}
+
+TEMPLATE = "{:15} SOA Serial: @b({})"
+
+def find_nameservers(domain):
+    nameservers = []
+    ns = dns.resolver.query(domain, "NS")
+    for rrset in ns.response.additional:
+        for a in rrset:
+            nameservers.append(a.address)
+    return nameservers
+
+def spawn_resolvers(nameservers):
+    resolvers = []
+    for ns in nameservers:
+        resolvers.append(dns.resolver.Resolver())
+        resolvers[-1].nameservers = [ns]
+    return resolvers
+
+def serials_gt(a, b):
+    # TODO: actually use the algorithm specified in RFC 1982
+    return int(a) > int(b)
+
+def serials_eq(a, b):
+    return int(a) == int(b)
+
+def check_soa_serial(domain, resolvers, serials):
+    answers = [domain]
+    new_serials = {}
+    updated = False
+    for r in resolvers:
+        soa = r.query(domain, "SOA")
+        n = r.nameservers[0]
+        s = soa[0].serial
+        if serials_gt(s, serials[n]):
+            answers.append(TEMPLATE.format(n, s) + " @b(@color(green)UPDATE)")
+            updated = True
+        elif serials_eq(s, serials[n]) and updated:
+            answers.append(TEMPLATE.format(n, s) + " @b(@color(yellow)UNCHANGED)")
+        else:
+            answers.append(TEMPLATE.format(n, s) + " @b(@color(yellow)REGRESSION)")
+            updated = True
+    return "\n".join(answers)
+
+def main():
+    domain = sys.argv[1]
+    print(domain)
+    resolvers = spawn_resolvers(find_nameservers(domain))
+    serials = {}
+    for r in resolvers:
+        serials[r.nameservers[0]] = "0"
+    while True:
+        message = check_soa_serial(domain, resolvers, serials)
+        if message:
+            zwrite.zwrite(message, **DEFAULT_ARGS)
+        time.sleep(300)
+
+if __name__ == "__main__":
+    main()