Added upload file id

Retrieve-DNSFile.ps1

@@ -2,7 +2,11 @@ Function Get-DNSTXT {
     [CmdletBinding()] param(
         [string] $Domain
     )
+    Try {
         return (Resolve-DnsName -Type TXT $Domain | Select-Object Strings | Format-Table -HideTableHeaders | Out-String -Width 1000).Replace("{", "").Replace("}", "").Trim()
+    } Catch [System.Management.Automation.CommandNotFoundException] {
+        return dig +short $Domain TXT
+    }
 }
 
 Function Get-DNSFile {
@@ -13,10 +17,10 @@ Function Get-DNSFile {
         [switch] $Write,
         [string] $OutPath
     )
-    $count = [int](Retrieve-DNSTXT -Domain "$Filename.count.$DNSName")
+    $count = [int](Get-DNSTXT -Domain "$Filename.count.$DNSName")
     $file_base64 = ""
     For ($i=0; $i -le $count; $i++) {
-        $file_base64 += (Retrieve-DNSTXT -Domain "$Filename.$i.$DNSName")
+        $file_base64 += (Get-DNSTXT -Domain "$Filename.$i.$DNSName")
     }
     "Base64 $file_base64"
     $file_string = [Text.Encoding]::Utf8.GetString([Convert]::FromBase64String($file_base64))
@@ -31,20 +35,25 @@ Function Get-DNSFile {
     }
 }
 
-function Push-DNSFile {
+Function Push-DNSFile {
     [CmdletBinding()] param(
         [string] $Filename = $(Read-Host -Prompt 'Enter a Filename'),
-        [string] $DNSName = $(Read-Host -Prompt 'Enter a DNSName'),
+        [string] $DNSName = $(Read-Host -Prompt 'Enter a DNSName')
-        [string] $Prefix = ""
     )
+    $content_id = [Convert]::ToBase64String([Text.Encoding]::UTF8.GetBytes((Get-FileHash -Path $Filename).ToString())).Substring(0,6)
     $content_binary = Get-Content -Path $Filename -Encoding utf8
     $content_base64 = [Convert]::ToBase64String([Text.Encoding]::UTF8.GetBytes($content_binary))
     $i = 0
     While ($content_base64) {
-        $url = ".$(Prefix)$(i)0.$(DNSName)"
+        $url = "."+$i+"-"+$content_id+"u."+$DNSName
         $len = 63 - $url.Length
+        if($len -le $content_base64.Length) {
             $content_part = $content_base64.Substring(0, $len)
             $content_base64 = $content_base64.Substring($len)
+        } else {
+            $content_part = $content_base64
+            $content_base64 = $false
+        }
         Get-DNSTXT -Domain ($content_part + $url)
         $i++
     }

server

@@ -84,9 +84,8 @@ class FileResolver(BaseResolver):
             pname = '.'.join(parts[:-2])
             path = self.directory + "/" + pname
             command = ''.join(parts[-2:-1])
-            # TODO: circumvent caching, eg by counting up
             if command.endswith("u"):
-                with open('/tmp/dns-srv.log', 'a') as f:
+                with open(f"/tmp/{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")))
                 return reply