Class: Memorandom::Plugins::RSA

Inherits:
Memorandom::PluginTemplate show all
Defined in:
lib/memorandom/plugins/rsa.rb

Constant Summary collapse

@@description = 
"This plugin looks for RSA keys by finding Bignum-encoded p-values"
@@confidence = 
0.90

Instance Attribute Summary

Attributes inherited from Memorandom::PluginTemplate

#hits, #scanner

Instance Method Summary collapse

Methods inherited from Memorandom::PluginTemplate

#confidence, confidence, #description, description, #initialize, #report_hit, #reset

Constructor Details

This class inherits a constructor from Memorandom::PluginTemplate

Instance Method Details

#scan(buffer, source_offset) ⇒ Object

Scan takes a buffer and an offset of where this buffer starts in the source



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# File 'lib/memorandom/plugins/rsa.rb', line 11

def scan(buffer, source_offset)

  key_lengths = [1024, 2048]

  key_lengths.each do |bits|
    p_size = bits / 16
    n_size = bits / 8

    found = []
    0.upto(buffer.length - (p_size + n_size)) do |p_offset|

      # Look for a prime of the right size (p or q)
      found_p = OpenSSL::BN.new( buffer[p_offset, p_size].unpack("H*").first.to_i(16).to_s )
      next unless found_p.prime?
      next unless found_p > 0x1000000000000000000000

      # Look for a modulus that matches the found p/q value
      0.upto(buffer.length - (p_size + n_size) ) do |n_offset|

        next if (n_offset < p_offset and (n_offset + n_size) > p_offset)
        next if (p_offset < n_offset and (p_offset + p_size) > n_offset)

        found_n = OpenSSL::BN.new(buffer[n_offset, n_size].unpack("H*").first.to_i(16).to_s )

        next if found_n == 0
        next if found_n == found_p
        next unless found_n > 0x1000000000000000000000
        next unless (found_n % found_p == 0)

        found << [found_p, found_n, p_offset]
      end
    end

    found = found.uniq 

    next unless found.length > 0

    mods = {}

    # Track the last unique p/q value for a potential modulus
    found.each do |info|
      mods[ info[1] ] ||= {}
      mods[ info[1] ][ info[0] ] = info[2]
    end
    p mods

    next 
    
    mods.keys.each do |n|
      uniq_pees = mods[n].keys.select do |k|
        mods[n].keys.reject {|x| x == k}.select{|x| n == (x * k) }
      end
    end


  end
end