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// Copyright (c) 2020 The Bitcoin Core developers
// Distributed under the MIT software license, see the accompanying
// file COPYING or http://www.opensource.org/licenses/mit-license.php.
#include <netaddress.h>
#include <test/fuzz/fuzz.h>
#include <util/asmap.h>
#include <cstdint>
#include <vector>
//! asmap code that consumes nothing
static const std::vector<bool> IPV6_PREFIX_ASMAP = {};
//! asmap code that consumes the 96 prefix bits of ::ffff:0/96 (IPv4-in-IPv6 map)
static const std::vector<bool> IPV4_PREFIX_ASMAP = {
true, true, false, true, true, true, true, true, true, true, false, false, false, false, false, false, false, false, // Match 0x00
true, true, false, true, true, true, true, true, true, true, false, false, false, false, false, false, false, false, // Match 0x00
true, true, false, true, true, true, true, true, true, true, false, false, false, false, false, false, false, false, // Match 0x00
true, true, false, true, true, true, true, true, true, true, false, false, false, false, false, false, false, false, // Match 0x00
true, true, false, true, true, true, true, true, true, true, false, false, false, false, false, false, false, false, // Match 0x00
true, true, false, true, true, true, true, true, true, true, false, false, false, false, false, false, false, false, // Match 0x00
true, true, false, true, true, true, true, true, true, true, false, false, false, false, false, false, false, false, // Match 0x00
true, true, false, true, true, true, true, true, true, true, false, false, false, false, false, false, false, false, // Match 0x00
true, true, false, true, true, true, true, true, true, true, false, false, false, false, false, false, false, false, // Match 0x00
true, true, false, true, true, true, true, true, true, true, false, false, false, false, false, false, false, false, // Match 0x00
true, true, false, true, true, true, true, true, true, true, true, true, true, true, true, true, true, true, // Match 0xFF
true, true, false, true, true, true, true, true, true, true, true, true, true, true, true, true, true, true // Match 0xFF
};
FUZZ_TARGET(asmap)
{
// Encoding: [7 bits: asmap size] [1 bit: ipv6?] [3-130 bytes: asmap] [4 or 16 bytes: addr]
if (buffer.size() < 1 + 3 + 4) return;
int asmap_size = 3 + (buffer[0] & 127);
bool ipv6 = buffer[0] & 128;
const size_t addr_size = ipv6 ? ADDR_IPV6_SIZE : ADDR_IPV4_SIZE;
if (buffer.size() < size_t(1 + asmap_size + addr_size)) return;
std::vector<bool> asmap = ipv6 ? IPV6_PREFIX_ASMAP : IPV4_PREFIX_ASMAP;
asmap.reserve(asmap.size() + 8 * asmap_size);
for (int i = 0; i < asmap_size; ++i) {
for (int j = 0; j < 8; ++j) {
asmap.push_back((buffer[1 + i] >> j) & 1);
}
}
if (!SanityCheckASMap(asmap, 128)) return;
const uint8_t* addr_data = buffer.data() + 1 + asmap_size;
CNetAddr net_addr;
if (ipv6) {
assert(addr_size == ADDR_IPV6_SIZE);
net_addr.SetLegacyIPv6({addr_data, addr_size});
} else {
assert(addr_size == ADDR_IPV4_SIZE);
in_addr ipv4;
memcpy(&ipv4, addr_data, addr_size);
net_addr.SetIP(CNetAddr{ipv4});
}
(void)net_addr.GetMappedAS(asmap);
}
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