asmap_direct.cpp raw

   1  // Copyright (c) 2020-2021 The Limenka developers
   2  // Distributed under the MIT software license, see the accompanying
   3  // file COPYING or http://www.opensource.org/licenses/mit-license.php.
   4  
   5  #include <netaddress.h>
   6  #include <util/asmap.h>
   7  #include <test/fuzz/fuzz.h>
   8  
   9  #include <cstdint>
  10  #include <optional>
  11  #include <vector>
  12  
  13  #include <assert.h>
  14  
  15  FUZZ_TARGET(asmap_direct)
  16  {
  17      // Encoding: [asmap using 1 bit / byte] 0xFF [addr using 1 bit / byte]
  18      std::optional<size_t> sep_pos_opt;
  19      for (size_t pos = 0; pos < buffer.size(); ++pos) {
  20          uint8_t x = buffer[pos];
  21          if ((x & 0xFE) == 0) continue;
  22          if (x == 0xFF) {
  23              if (sep_pos_opt) return;
  24              sep_pos_opt = pos;
  25          } else {
  26              return;
  27          }
  28      }
  29      if (!sep_pos_opt) return; // Needs exactly 1 separator
  30      const size_t sep_pos{sep_pos_opt.value()};
  31      if (buffer.size() - sep_pos - 1 > 128) return; // At most 128 bits in IP address
  32  
  33      // Checks on asmap
  34      std::vector<bool> asmap(buffer.begin(), buffer.begin() + sep_pos);
  35      if (SanityCheckASMap(asmap, buffer.size() - 1 - sep_pos)) {
  36          // Verify that for valid asmaps, no prefix (except up to 7 zero padding bits) is valid.
  37          std::vector<bool> asmap_prefix = asmap;
  38          while (!asmap_prefix.empty() && asmap_prefix.size() + 7 > asmap.size() && asmap_prefix.back() == false) {
  39              asmap_prefix.pop_back();
  40          }
  41          while (!asmap_prefix.empty()) {
  42              asmap_prefix.pop_back();
  43              assert(!SanityCheckASMap(asmap_prefix, buffer.size() - 1 - sep_pos));
  44          }
  45          // No address input should trigger assertions in interpreter
  46          std::vector<bool> addr(buffer.begin() + sep_pos + 1, buffer.end());
  47          (void)Interpret(asmap, addr);
  48      }
  49  }
  50