Updated README and code, almost ready for testing

README.md

@@ -5,4 +5,15 @@ This tool is designed to detect passive DNS servers that are logging DNS queries
 
 The program operates by accepting a list of DNS resolver addresses and a seed value for subdomain generation. It then asynchronously queries each resolver with a dynamically generated subdomain, based on the provided seed, targeting a specific domain. The asynchronous nature of the tool allows for high-throughput and efficient querying, making it suitable for scanning a large number of resolvers in a short period. Users should note that while this tool provides valuable insights into DNS logging practices, it should be used responsibly and in compliance with applicable network and privacy regulations. It serves as a powerful instrument for network administrators, security researchers, and privacy advocates to understand and evaluate the extent of passive DNS logging in their networks or across various resolvers.
 
-## WORK IN PROGRESS (STAY TUNED)
+## WORK IN PROGRESS (STAY TUNED)
+
+- Right now we can MASS query a subdomain on a domain or list of domains using a list of resolvers or the resolvers from public-dns.info
+- Need to generate a seed per-dns server that can be included in the subdomain so it can be reversed back to a know which specific dns server is logging all dns requests.
+- Subdomain should be entirely random, have to look into commonly seen subdomains, but something like:
+    - de.220.ftp.domain.com 
+    - astro.login.domain.net 
+    - customer-cdn.1220.domain.org
+
+Every sweep, we will generate a random seed for each dns server and save it to a seed.key file.
+
+This is all very theoretical right now, interested to see how this pans out.

pdknockr.py

@@ -10,7 +10,7 @@ except ImportError:
     raise SystemExit('missing required \'aiodns\' module (pip install aiodns)')
 
 
-async def dns_lookup(domain: str, subdomain: str, dns_server: str):
+async def dns_lookup(domain: str, subdomain: str, dns_server: str, dns_type: str, semaphore: asyncio.Semaphore):
     '''
     Perform a DNS lookup on a target domain.
     
@@ -18,39 +18,47 @@ async def dns_lookup(domain: str, subdomain: str, dns_server: str):
     :param subdomain: The subdomain to look up.
     :param dns_server: The DNS server to perform the lookup on.
     '''
-    domain = f'{subdomain}.{domain}'
-    resolver = aiodns.DNSResolver(nameservers=[dns_server])
-    try:
-        answers = await resolver.query(domain, 'A')
-        print(f'[\033[92mDONE\033[0m] Knocking \033[96m{domain}\033[0m on \033[93m{dns_server}\033[0m')
-    except Exception as e:
-        print(f'Error resolving {domain} using {dns_server}: {e}')
+    async with semaphore:
+        target = f'{subdomain}.{domain}'
+        resolver = aiodns.DNSResolver(nameservers=[dns_server])
+        try:
+            await resolver.query(target, dns_type)
+            print(f'[\033[92mDONE\033[0m] Knocking \033[96m{target}\033[0m on \033[93m{dns_server}\033[0m')
+        except Exception as e:
+            print(f'[\033[31mFAIL\033[0m] Knocking \033[96m{target}\033[0m on \033[93m{dns_server}\033[0m \033[90m({e})\033[0m')
 
 
-async def main(input_file: str, domains: str, subdomain: str, concurrency: int):
+async def main(args):
     '''
     Main function for the program.
     
-    :param input_file: The file containing the list of domains to perform lookups on.
-    :param domains: The comma seperated list of domains to perform lookups on.
-    :param subdomain: The subdomain to look up.
-    :param concurrency: The maximum number of concurrent lookups to perform.
+    :param args: The arguments passed to the program.
     '''
-    semaphore = asyncio.BoundedSemaphore(concurrency)
+    global dns_servers
+
+    semaphore = asyncio.BoundedSemaphore(args.concurrency)
+    tasks = []
 
     if args.domains:
-        domains = args.domains.split(',')
-        async for domain in domains:
+        for domain in args.domains.split(','):
             for dns_server in dns_servers:
-                await semaphore.acquire()
-                asyncio.create_task(dns_lookup(domain, subdomain, dns_server, semaphore))
+                if len(tasks) < args.concurrency:
+                    task = asyncio.create_task(dns_lookup(domain, args.subdomain, dns_server, args.rectype, semaphore))
+                    tasks.append(task)
+                else:
+                    done, pending = await asyncio.wait(tasks, return_when=asyncio.FIRST_COMPLETED)
+                    tasks = list(pending)
 
     elif args.input:
-        async with asyncio.open_file(input_file, 'r') as file:
-            async for domain in file:
-                await semaphore.acquire()
-                dns_server = random.choice(dns_servers)
-                asyncio.create_task(dns_lookup(domain, subdomain, dns_server, semaphore))
+        async with asyncio.open_file(args.input, 'r') as file:
+            for domain in file:
+                for dns_server in dns_servers:
+                    if len(tasks) < args.concurrency:
+                        task = asyncio.create_task(dns_lookup(domain, args.subdomain, dns_server, args.rectype, semaphore))
+                        tasks.append(task)
+                    else:
+                        done, pending = await asyncio.wait(tasks, return_when=asyncio.FIRST_COMPLETED)
+                        tasks = list(pending)
 
 
 
@@ -63,20 +71,24 @@ if __name__ == '__main__':
     parser.add_argument('-d', '--domains', help='Comma seperate list of domains')
     parser.add_argument('-i', '--input', help='File containing list of domains')
     parser.add_argument('-s', '--subdomain', help='Subdomain to look up')
-    parser.add_argument('-c', '--concurrency', type=int, default=50, help='Concurrency limit')
+    parser.add_argument('-c', '--concurrency', type=int, default=50, help='Concurrency limit (default: 50)')
     parser.add_argument('-r', '--resolvers', help='File containing list of DNS resolvers (uses public-dns.info if not specified)')
+    parser.add_argument('-rt', '--rectype', default='A', help='DNS record type (default: A)')
     args = parser.parse_args()
 
-    if not args.input and not args.domain:
+    if not args.input and not args.domains:
         raise SystemExit('no domains specified')
     
-    if args.input and args.domain:
+    elif args.input and args.domains:
         raise SystemExit('cannot specify both domain and input file')
     
-    if args.input and not os.path.exists(args.input):
+    elif args.input and not os.path.exists(args.input):
         raise SystemExit('input file does not exist')
+
+    elif args.rectype and args.rectype not in ['A', 'AAAA', 'CNAME', 'MX', 'NS', 'PTR', 'SOA', 'SRV', 'TXT']:
+        raise SystemExit('invalid record type')
     
-    if args.resolvers:
+    elif args.resolvers:
         if os.path.exists(args.resolvers):
             with open(args.resolvers, 'r') as file:
                 dns_servers = [item.strip() for item in file.readlines() if item.strip()]
@@ -90,4 +102,4 @@ if __name__ == '__main__':
         dns_servers = urllib.request.urlopen('https://public-dns.info/nameservers.txt').read().decode().split('\n')
         print(f'Loaded {len(dns_servers):,} DNS servers from public-dns.info')
 
-    asyncio.run(main(args.input, args.domain, args.subdomain, args.concurrency))
+    asyncio.run(main(args))