1  // Copyright (c) 2024 The Bitcoin Core 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 <test/fuzz/FuzzedDataProvider.h>
 6  #include <test/fuzz/fuzz.h>
 7  #include <test/fuzz/util.h>
 8  #include <test/fuzz/util/net.h>
 9  
10  #include <common/pcp.h>
11  #include <util/check.h>
12  
13  using namespace std::literals;
14  
15  //! Fixed nonce to use in PCP port mapping requests.
16  constexpr PCPMappingNonce PCP_NONCE{0x11, 0x22, 0x33, 0x44, 0x55, 0x66, 0x77, 0x88, 0x99, 0xaa, 0xbb, 0xcc};
17  
18  //! Number of attempts to request a NAT-PMP or PCP port mapping to the gateway.
19  constexpr int NUM_TRIES{5};
20  
21  //! Timeout for each attempt to request a port mapping.
22  constexpr std::chrono::duration TIMEOUT{100ms};
23  
24  void port_map_target_init()
25  {
26      LogInstance().DisableLogging();
27  }
28  
29  FUZZ_TARGET(pcp_request_port_map, .init = port_map_target_init)
30  {
31      FuzzedDataProvider fuzzed_data_provider{buffer.data(), buffer.size()};
32  
33      // Create a mocked socket between random (and potentially invalid) client and gateway addresses.
34      CreateSock = [&](int domain, int type, int protocol) {
35          if ((domain == AF_INET || domain == AF_INET6) && type == SOCK_DGRAM && protocol == IPPROTO_UDP) {
36              return std::make_unique<FuzzedSock>(fuzzed_data_provider);
37          }
38          return std::unique_ptr<FuzzedSock>();
39      };
40  
41      // Perform the port mapping request. The mocked socket will return fuzzer-provided data.
42      const auto gateway_addr{ConsumeNetAddr(fuzzed_data_provider)};
43      const auto local_addr{ConsumeNetAddr(fuzzed_data_provider)};
44      const auto port{fuzzed_data_provider.ConsumeIntegral<uint16_t>()};
45      const auto lifetime{fuzzed_data_provider.ConsumeIntegral<uint32_t>()};
46      const auto res{PCPRequestPortMap(PCP_NONCE, gateway_addr, local_addr, port, lifetime, NUM_TRIES, TIMEOUT)};
47  
48      // In case of success the mapping must be consistent with the request.
49      if (const MappingResult* mapping = std::get_if<MappingResult>(&res)) {
50          Assert(mapping);
51          Assert(mapping->internal.GetPort() == port);
52          mapping->ToString();
53      }
54  }
55  
56  FUZZ_TARGET(natpmp_request_port_map, .init = port_map_target_init)
57  {
58      FuzzedDataProvider fuzzed_data_provider{buffer.data(), buffer.size()};
59  
60      // Create a mocked socket between random (and potentially invalid) client and gateway addresses.
61      CreateSock = [&](int domain, int type, int protocol) {
62          if (domain == AF_INET && type == SOCK_DGRAM && protocol == IPPROTO_UDP) {
63              return std::make_unique<FuzzedSock>(fuzzed_data_provider);
64          }
65          return std::unique_ptr<FuzzedSock>();
66      };
67  
68      // Perform the port mapping request. The mocked socket will return fuzzer-provided data.
69      const auto gateway_addr{ConsumeNetAddr(fuzzed_data_provider)};
70      const auto port{fuzzed_data_provider.ConsumeIntegral<uint16_t>()};
71      const auto lifetime{fuzzed_data_provider.ConsumeIntegral<uint32_t>()};
72      const auto res{NATPMPRequestPortMap(gateway_addr, port, lifetime, NUM_TRIES, TIMEOUT)};
73  
74      // In case of success the mapping must be consistent with the request.
75      if (const MappingResult* mapping = std::get_if<MappingResult>(&res)) {
76          Assert(mapping);
77          Assert(mapping->internal.GetPort() == port);
78          mapping->ToString();
79      }
80  }