net: change CNetAddr::ip to have flexible size

Before this change `CNetAddr::ip` was a fixed-size array of 16 bytes,
not being able to store larger addresses (e.g. TORv3) and encoded
smaller ones as 16-byte IPv6 addresses.

Change its type to `prevector`, so that it can hold larger addresses and
do not disguise non-IPv6 addresses as IPv6. So the IPv4 address
`1.2.3.4` is now encoded as `01020304` instead of
`00000000000000000000FFFF01020304`.

Rename `CNetAddr::ip` to `CNetAddr::m_addr` because it is not an "IP" or
"IP address" (TOR addresses are not IP addresses).

In order to preserve backward compatibility with serialization (where
e.g. `1.2.3.4` is serialized as `00000000000000000000FFFF01020304`)
introduce `CNetAddr` dedicated legacy serialize/unserialize methods.

Adjust `CSubNet` accordingly. Still use `CSubNet::netmask[]` of fixed 16
bytes, but use the first 4 for IPv4 (not the last 4). Only allow
subnetting for IPv4 and IPv6.

Co-authored-by: Carl Dong <contact@carldong.me>

1 files changed, 1 insertions, 4 deletions

diff --git a/src/test/fuzz/netaddress.cpp b/src/test/fuzz/netaddress.cpp
index 2901c704f6..8252f38726 100644
--- a/src/test/fuzz/netaddress.cpp
+++ b/src/test/fuzz/netaddress.cpp
@@ -17,9 +17,6 @@ void test_one_input(const std::vector<uint8_t>& buffer)
     FuzzedDataProvider fuzzed_data_provider(buffer.data(), buffer.size());
 
     const CNetAddr net_addr = ConsumeNetAddr(fuzzed_data_provider);
-    for (int i = 0; i < 15; ++i) {
-        (void)net_addr.GetByte(i);
-    }
     (void)net_addr.GetHash();
     (void)net_addr.GetNetClass();
     if (net_addr.GetNetwork() == Network::NET_IPV4) {
@@ -78,7 +75,7 @@ void test_one_input(const std::vector<uint8_t>& buffer)
     (void)net_addr.ToString();
     (void)net_addr.ToStringIP();
 
-    const CSubNet sub_net{net_addr, fuzzed_data_provider.ConsumeIntegral<int32_t>()};
+    const CSubNet sub_net{net_addr, fuzzed_data_provider.ConsumeIntegral<uint8_t>()};
     (void)sub_net.IsValid();
     (void)sub_net.ToString();