refactor: Use span of bytes for asmap

This prevents holding the asmap data in memory twice.

Also modernizes the logging in util/asmap.cpp (LogPrintf -> LogInfo).

src/bench/addrman.cpp

@@ -24,7 +24,7 @@
 static constexpr size_t NUM_SOURCES = 64;
 static constexpr size_t NUM_ADDRESSES_PER_SOURCE = 256;
 
-static NetGroupManager EMPTY_NETGROUPMAN{std::vector<bool>()};
+static NetGroupManager EMPTY_NETGROUPMAN{NetGroupManager::NoAsmap()};
 static constexpr uint32_t ADDRMAN_CONSISTENCY_CHECK_RATIO{0};
 
 static std::vector<CAddress> g_sources;

src/init.cpp

@@ -1431,9 +1431,10 @@ bool AppInitMain(NodeContext& node, interfaces::BlockAndHeaderTipInfo* tip_info)
     ApplyArgsManOptions(args, peerman_opts);
 
     {
-
+        // Read asmap file or embedded data if configured and initialize
-        // Read asmap file if configured
+        // Netgroupman with or without it
-        std::vector<bool> asmap;
+        assert(!node.netgroupman);
+        uint256 asmap_version;
         if (args.IsArgSet("-asmap") && !args.IsArgNegated("-asmap")) {
             fs::path asmap_path = args.GetPathArg("-asmap", DEFAULT_ASMAP_FILENAME);
             if (!asmap_path.is_absolute()) {
@@ -1443,21 +1444,19 @@ bool AppInitMain(NodeContext& node, interfaces::BlockAndHeaderTipInfo* tip_info)
                 InitError(strprintf(_("Could not find asmap file %s"), fs::quoted(fs::PathToString(asmap_path))));
                 return false;
             }
-            asmap = DecodeAsmap(asmap_path);
+            std::vector<std::byte> asmap{DecodeAsmap(asmap_path)};
             if (asmap.size() == 0) {
                 InitError(strprintf(_("Could not parse asmap file %s"), fs::quoted(fs::PathToString(asmap_path))));
                 return false;
             }
-            const uint256 asmap_version = (HashWriter{} << asmap).GetHash();
+            node.netgroupman = std::make_unique<NetGroupManager>(NetGroupManager::WithLoadedAsmap(asmap));
+            asmap_version = AsmapChecksum(asmap);
             LogPrintf("Using asmap version %s for IP bucketing\n", asmap_version.ToString());
         } else {
+            node.netgroupman = std::make_unique<NetGroupManager>(NetGroupManager::NoAsmap());
             LogPrintf("Using /16 prefix for IP bucketing\n");
         }
 
-        // Initialize netgroup manager
-        assert(!node.netgroupman);
-        node.netgroupman = std::make_unique<NetGroupManager>(std::move(asmap));
-
         // Initialize addrman
         assert(!node.addrman);
         uiInterface.InitMessage(_("Loading P2P addresses…"));

src/netgroup.cpp

@@ -6,13 +6,13 @@
 
 #include <hash.h>
 #include <logging.h>
+#include <uint256.h>
 #include <util/asmap.h>
 
 uint256 NetGroupManager::GetAsmapChecksum() const
 {
     if (!m_asmap.size()) return {};
-
+    return AsmapChecksum(m_asmap);
-    return (HashWriter{} << m_asmap).GetHash();
 }
 
 std::vector<unsigned char> NetGroupManager::GetGroup(const CNetAddr& address) const
@@ -81,30 +81,25 @@ std::vector<unsigned char> NetGroupManager::GetGroup(const CNetAddr& address) co
 uint32_t NetGroupManager::GetMappedAS(const CNetAddr& address) const
 {
     uint32_t net_class = address.GetNetClass();
-    if (m_asmap.size() == 0 || (net_class != NET_IPV4 && net_class != NET_IPV6)) {
+    if (m_asmap.empty() || (net_class != NET_IPV4 && net_class != NET_IPV6)) {
         return 0; // Indicates not found, safe because AS0 is reserved per RFC7607.
     }
-    std::vector<bool> ip_bits(128);
+    std::vector<std::byte> ip_bits(16);
     if (address.HasLinkedIPv4()) {
         // For lookup, treat as if it was just an IPv4 address (IPV4_IN_IPV6_PREFIX + IPv4 bits)
         for (int8_t byte_i = 0; byte_i < 12; ++byte_i) {
-            for (uint8_t bit_i = 0; bit_i < 8; ++bit_i) {
+            ip_bits[byte_i] = static_cast<std::byte>(IPV4_IN_IPV6_PREFIX[byte_i]);
-                ip_bits[byte_i * 8 + bit_i] = (IPV4_IN_IPV6_PREFIX[byte_i] >> (7 - bit_i)) & 1;
-            }
         }
         uint32_t ipv4 = address.GetLinkedIPv4();
-        for (int i = 0; i < 32; ++i) {
+        for (int i = 0; i < 4; ++i) {
-            ip_bits[96 + i] = (ipv4 >> (31 - i)) & 1;
+            ip_bits[12 + i] = static_cast<std::byte>((ipv4 >> (24 - i * 8)) & 0xFF);
         }
     } else {
         // Use all 128 bits of the IPv6 address otherwise
         assert(address.IsIPv6());
         auto addr_bytes = address.GetAddrBytes();
         for (int8_t byte_i = 0; byte_i < 16; ++byte_i) {
-            uint8_t cur_byte = addr_bytes[byte_i];
+            ip_bits[byte_i] = static_cast<std::byte>(addr_bytes[byte_i]);
-            for (uint8_t bit_i = 0; bit_i < 8; ++bit_i) {
-                ip_bits[byte_i * 8 + bit_i] = (cur_byte >> (7 - bit_i)) & 1;
-            }
         }
     }
     uint32_t mapped_as = Interpret(m_asmap, ip_bits);

src/netgroup.h

@@ -15,9 +15,18 @@
  */
 class NetGroupManager {
 public:
-    explicit NetGroupManager(std::vector<bool> asmap)
+    static NetGroupManager WithEmbeddedAsmap(std::span<const std::byte> asmap) {
-        : m_asmap{std::move(asmap)}
+        return NetGroupManager(asmap, {});
-    {}
+    }
+
+    static NetGroupManager WithLoadedAsmap(std::vector<std::byte> loaded_asmap) {
+        std::span<const std::byte> asmap_span(loaded_asmap);
+        return NetGroupManager(asmap_span, std::move(loaded_asmap));
+    }
+
+    static NetGroupManager NoAsmap() {
+        return NetGroupManager({}, {});
+    }
 
     /** Get a checksum identifying the asmap being used. */
     uint256 GetAsmapChecksum() const;
@@ -52,7 +61,10 @@ public:
     bool UsingASMap() const;
 
 private:
-    /** Compressed IP->ASN mapping, loaded from a file when a node starts.
+    /** Compressed IP->ASN mapping.
+     *
+     * Data may beloaded from a file when a node starts or embedded in the
+     * binary.
      *
      * This mapping is then used for bucketing nodes in Addrman and for
      * ensuring we connect to a diverse set of peers in Connman. The map is
@@ -69,8 +81,17 @@ private:
      * re-bucketed.
      *
      * This is initialized in the constructor, const, and therefore is
-     * thread-safe. */
+     * thread-safe. m_asmap can either point to m_loaded_asmap which holds
-    const std::vector<bool> m_asmap;
+     * data loaded from an external file at runtime or it can point to embedded
+     * asmap data.
+     */
+    const std::span<const std::byte>  m_asmap;
+    std::vector<std::byte> m_loaded_asmap;
+
+    explicit NetGroupManager(std::span<const std::byte> asmap, std::vector<std::byte> loaded_asmap)
+        : m_asmap(asmap.empty() ? std::span<const std::byte>() : asmap),
+          m_loaded_asmap(std::move(loaded_asmap))
+    {}
 };
 
 #endif // BITCOIN_NETGROUP_H

src/test/addrman_tests.cpp

@@ -24,7 +24,7 @@ using namespace std::literals;
 using node::NodeContext;
 using util::ToString;
 
-static NetGroupManager EMPTY_NETGROUPMAN{std::vector<bool>()};
+static NetGroupManager EMPTY_NETGROUPMAN{NetGroupManager::NoAsmap()};
 static const bool DETERMINISTIC{true};
 
 static int32_t GetCheckRatio(const NodeContext& node_ctx)
@@ -46,20 +46,6 @@ static CService ResolveService(const std::string& ip, uint16_t port = 0)
     return serv.value_or(CService{});
 }
 
-
-static std::vector<bool> FromBytes(std::span<const std::byte> source)
-{
-    int vector_size(source.size() * 8);
-    std::vector<bool> result(vector_size);
-    for (int byte_i = 0; byte_i < vector_size / 8; ++byte_i) {
-        uint8_t cur_byte{std::to_integer<uint8_t>(source[byte_i])};
-        for (int bit_i = 0; bit_i < 8; ++bit_i) {
-            result[byte_i * 8 + bit_i] = (cur_byte >> bit_i) & 1;
-        }
-    }
-    return result;
-}
-
 BOOST_FIXTURE_TEST_SUITE(addrman_tests, BasicTestingSetup)
 
 BOOST_AUTO_TEST_CASE(addrman_simple)
@@ -592,8 +578,7 @@ BOOST_AUTO_TEST_CASE(caddrinfo_get_new_bucket_legacy)
 // 101.8.0.0/16 AS8
 BOOST_AUTO_TEST_CASE(caddrinfo_get_tried_bucket)
 {
-    std::vector<bool> asmap = FromBytes(test::data::asmap);
+    NetGroupManager ngm_asmap{NetGroupManager::WithEmbeddedAsmap(test::data::asmap)};
-    NetGroupManager ngm_asmap{asmap};
 
     CAddress addr1 = CAddress(ResolveService("250.1.1.1", 8333), NODE_NONE);
     CAddress addr2 = CAddress(ResolveService("250.1.1.1", 9999), NODE_NONE);
@@ -646,8 +631,7 @@ BOOST_AUTO_TEST_CASE(caddrinfo_get_tried_bucket)
 
 BOOST_AUTO_TEST_CASE(caddrinfo_get_new_bucket)
 {
-    std::vector<bool> asmap = FromBytes(test::data::asmap);
+    NetGroupManager ngm_asmap{NetGroupManager::WithEmbeddedAsmap(test::data::asmap)};
-    NetGroupManager ngm_asmap{asmap};
 
     CAddress addr1 = CAddress(ResolveService("250.1.2.1", 8333), NODE_NONE);
     CAddress addr2 = CAddress(ResolveService("250.1.2.1", 9999), NODE_NONE);
@@ -724,8 +708,7 @@ BOOST_AUTO_TEST_CASE(caddrinfo_get_new_bucket)
 
 BOOST_AUTO_TEST_CASE(addrman_serialization)
 {
-    std::vector<bool> asmap1 = FromBytes(test::data::asmap);
+    NetGroupManager netgroupman{NetGroupManager::WithEmbeddedAsmap(test::data::asmap)};
-    NetGroupManager netgroupman{asmap1};
 
     const auto ratio = GetCheckRatio(m_node);
     auto addrman_asmap1 = std::make_unique<AddrMan>(netgroupman, DETERMINISTIC, ratio);

src/test/fuzz/asmap.cpp

@@ -6,28 +6,18 @@
 #include <netgroup.h>
 #include <test/fuzz/fuzz.h>
 #include <util/asmap.h>
+#include <util/strencodings.h>
 
 #include <cstdint>
 #include <vector>
 
+using namespace util::hex_literals;
+
 //! asmap code that consumes nothing
-static const std::vector<bool> IPV6_PREFIX_ASMAP = {};
+static const std::vector<std::byte> 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 = {
+static const auto IPV4_PREFIX_ASMAP = "fb03ec0fb03fc0fe00fb03ec0fb03fc0fe00fb03ec0fb0fffffeff"_hex_v;
-    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)
 {
@@ -37,13 +27,14 @@ FUZZ_TARGET(asmap)
     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;
+    std::vector<std::byte> asmap_vec = ipv6 ? IPV6_PREFIX_ASMAP : IPV4_PREFIX_ASMAP;
-    asmap.reserve(asmap.size() + 8 * asmap_size);
     for (int i = 0; i < asmap_size; ++i) {
+        uint8_t byte = buffer[1 + i];
         for (int j = 0; j < 8; ++j) {
-            asmap.push_back((buffer[1 + i] >> j) & 1);
+            asmap_vec.push_back(static_cast<std::byte>((byte >> j) & 1));
         }
     }
+    std::span<const std::byte> asmap(asmap_vec);
     if (!SanityCheckASMap(asmap, 128)) return;
 
     const uint8_t* addr_data = buffer.data() + 1 + asmap_size;
@@ -57,6 +48,6 @@ FUZZ_TARGET(asmap)
         memcpy(&ipv4, addr_data, addr_size);
         net_addr.SetIP(CNetAddr{ipv4});
     }
-    NetGroupManager netgroupman{asmap};
+    NetGroupManager netgroupman{NetGroupManager::WithEmbeddedAsmap(asmap)};
     (void)netgroupman.GetMappedAS(net_addr);
 }

src/test/fuzz/asmap_direct.cpp

@@ -31,19 +31,21 @@ FUZZ_TARGET(asmap_direct)
     if (buffer.size() - sep_pos - 1 > 128) return; // At most 128 bits in IP address
 
     // Checks on asmap
-    std::vector<bool> asmap(buffer.begin(), buffer.begin() + sep_pos);
+    std::vector<std::byte> asmap(reinterpret_cast<const std::byte*>(buffer.data()),
-    if (SanityCheckASMap(asmap, buffer.size() - 1 - sep_pos)) {
+                                 reinterpret_cast<const std::byte*>(buffer.data() + sep_pos));
+    if (SanityCheckASMap(std::span<const std::byte>(asmap), buffer.size() - 1 - sep_pos)) {
         // Verify that for valid asmaps, no prefix (except up to 7 zero padding bits) is valid.
-        std::vector<bool> asmap_prefix = asmap;
+        std::vector<std::byte> asmap_prefix = asmap;
-        while (!asmap_prefix.empty() && asmap_prefix.size() + 7 > asmap.size() && asmap_prefix.back() == false) {
+        while (!asmap_prefix.empty() && asmap_prefix.size() + 7 > asmap.size() && asmap_prefix.back() == std::byte{0}) {
             asmap_prefix.pop_back();
         }
         while (!asmap_prefix.empty()) {
             asmap_prefix.pop_back();
-            assert(!SanityCheckASMap(asmap_prefix, buffer.size() - 1 - sep_pos));
+            assert(!SanityCheckASMap(std::span<const std::byte>(asmap_prefix), buffer.size() - 1 - sep_pos));
         }
         // No address input should trigger assertions in interpreter
-        std::vector<bool> addr(buffer.begin() + sep_pos + 1, buffer.end());
+        std::vector<std::byte> addr(reinterpret_cast<const std::byte*>(buffer.data() + sep_pos + 1),
-        (void)Interpret(asmap, addr);
+                                    reinterpret_cast<const std::byte*>(buffer.data() + buffer.size()));
+        (void)Interpret(std::span<const std::byte>(asmap), std::span<const std::byte>(addr));
     }
 }

src/test/fuzz/p2p_handshake.cpp

@@ -48,7 +48,7 @@ FUZZ_TARGET(p2p_handshake, .init = ::initialize)
     chainman.ResetIbd();
 
     node::Warnings warnings{};
-    NetGroupManager netgroupman{{}};
+    NetGroupManager netgroupman{NetGroupManager::NoAsmap()};
     AddrMan addrman{netgroupman, /*deterministic=*/true, 0};
     auto peerman = PeerManager::make(connman, addrman,
                                      /*banman=*/nullptr, chainman,

src/test/fuzz/util.h

@@ -65,11 +65,6 @@ template<typename B = uint8_t>
     return ret;
 }
 
-[[nodiscard]] inline std::vector<bool> ConsumeRandomLengthBitVector(FuzzedDataProvider& fuzzed_data_provider, const std::optional<size_t>& max_length = std::nullopt) noexcept
-{
-    return BytesToBits(ConsumeRandomLengthByteVector(fuzzed_data_provider, max_length));
-}
-
 [[nodiscard]] inline DataStream ConsumeDataStream(FuzzedDataProvider& fuzzed_data_provider, const std::optional<size_t>& max_length = std::nullopt) noexcept
 {
     return DataStream{ConsumeRandomLengthByteVector(fuzzed_data_provider, max_length)};

src/test/fuzz/util/net.h

@@ -210,9 +210,11 @@ public:
 
 [[nodiscard]] inline NetGroupManager ConsumeNetGroupManager(FuzzedDataProvider& fuzzed_data_provider) noexcept
 {
-    std::vector<bool> asmap = ConsumeRandomLengthBitVector(fuzzed_data_provider);
+    std::vector<std::byte> asmap{ConsumeRandomLengthByteVector<std::byte>(fuzzed_data_provider)};
-    if (!SanityCheckASMap(asmap, 128)) asmap.clear();
+    if (!SanityCheckASMap(std::span<std::byte>(asmap), 128)) {
-    return NetGroupManager(asmap);
+        return NetGroupManager::NoAsmap();
+    }
+    return NetGroupManager::WithLoadedAsmap(asmap);
 }
 
 inline CSubNet ConsumeSubNet(FuzzedDataProvider& fuzzed_data_provider) noexcept

src/test/netbase_tests.cpp

@@ -323,7 +323,7 @@ BOOST_AUTO_TEST_CASE(subnet_test)
 
 BOOST_AUTO_TEST_CASE(netbase_getgroup)
 {
-    NetGroupManager netgroupman{std::vector<bool>()}; // use /16
+    NetGroupManager netgroupman{NetGroupManager::NoAsmap()}; // use /16
     BOOST_CHECK(netgroupman.GetGroup(ResolveIP("127.0.0.1")) == std::vector<unsigned char>({0})); // Local -> !Routable()
     BOOST_CHECK(netgroupman.GetGroup(ResolveIP("257.0.0.1")) == std::vector<unsigned char>({0})); // !Valid -> !Routable()
     BOOST_CHECK(netgroupman.GetGroup(ResolveIP("10.0.0.1")) == std::vector<unsigned char>({0})); // RFC1918 -> !Routable()

src/test/util/setup_common.cpp

@@ -317,7 +317,7 @@ TestingSetup::TestingSetup(
 
     if (!opts.setup_net) return;
 
-    m_node.netgroupman = std::make_unique<NetGroupManager>(/*asmap=*/std::vector<bool>());
+    m_node.netgroupman = std::make_unique<NetGroupManager>(NetGroupManager::NoAsmap());
     m_node.addrman = std::make_unique<AddrMan>(*m_node.netgroupman,
                                                /*deterministic=*/false,
                                                m_node.args->GetIntArg("-checkaddrman", 0));

src/util/asmap.cpp

@@ -5,6 +5,7 @@
 #include <util/asmap.h>
 
 #include <clientversion.h>
+#include <hash.h>
 #include <logging.h>
 #include <serialize.h>
 #include <streams.h>
@@ -14,6 +15,7 @@
 #include <bit>
 #include <cassert>
 #include <cstdio>
+#include <span>
 #include <utility>
 #include <vector>
 
@@ -21,15 +23,14 @@ namespace {
 
 constexpr uint32_t INVALID = 0xFFFFFFFF;
 
-uint32_t DecodeBits(std::vector<bool>::const_iterator& bitpos, const std::vector<bool>::const_iterator& endpos, uint8_t minval, const std::vector<uint8_t> &bit_sizes)
+uint32_t DecodeBits(size_t& bitpos, const std::span<const std::byte>& data, uint8_t minval, const std::vector<uint8_t>& bit_sizes)
 {
     uint32_t val = minval;
     bool bit;
-    for (std::vector<uint8_t>::const_iterator bit_sizes_it = bit_sizes.begin();
+    for (auto bit_sizes_it = bit_sizes.begin(); bit_sizes_it != bit_sizes.end(); ++bit_sizes_it) {
-        bit_sizes_it != bit_sizes.end(); ++bit_sizes_it) {
         if (bit_sizes_it + 1 != bit_sizes.end()) {
-            if (bitpos == endpos) break;
+            if (bitpos >= data.size() * 8) break;
-            bit = *bitpos;
+            bit = (std::to_integer<uint8_t>(data[bitpos / 8]) >> (bitpos % 8)) & 1;
             bitpos++;
         } else {
             bit = 0;
@@ -38,8 +39,8 @@ uint32_t DecodeBits(std::vector<bool>::const_iterator& bitpos, const std::vector
             val += (1 << *bit_sizes_it);
         } else {
             for (int b = 0; b < *bit_sizes_it; b++) {
-                if (bitpos == endpos) return INVALID; // Reached EOF in mantissa
+                if (bitpos >= data.size() * 8) return INVALID; // Reached EOF in mantissa
-                bit = *bitpos;
+                bit = (std::to_integer<uint8_t>(data[bitpos / 8]) >> (bitpos % 8)) & 1;
                 bitpos++;
                 val += bit << (*bit_sizes_it - 1 - b);
             }
@@ -58,69 +59,68 @@ enum class Instruction : uint32_t
 };
 
 const std::vector<uint8_t> TYPE_BIT_SIZES{0, 0, 1};
-Instruction DecodeType(std::vector<bool>::const_iterator& bitpos, const std::vector<bool>::const_iterator& endpos)
+Instruction DecodeType(size_t& bitpos, const std::span<const std::byte>& data)
 {
-    return Instruction(DecodeBits(bitpos, endpos, 0, TYPE_BIT_SIZES));
+    return Instruction(DecodeBits(bitpos, data, 0, TYPE_BIT_SIZES));
 }
 
 const std::vector<uint8_t> ASN_BIT_SIZES{15, 16, 17, 18, 19, 20, 21, 22, 23, 24};
-uint32_t DecodeASN(std::vector<bool>::const_iterator& bitpos, const std::vector<bool>::const_iterator& endpos)
+uint32_t DecodeASN(size_t& bitpos, const std::span<const std::byte>& data)
 {
-    return DecodeBits(bitpos, endpos, 1, ASN_BIT_SIZES);
+    return DecodeBits(bitpos, data, 1, ASN_BIT_SIZES);
 }
 
 
 const std::vector<uint8_t> MATCH_BIT_SIZES{1, 2, 3, 4, 5, 6, 7, 8};
-uint32_t DecodeMatch(std::vector<bool>::const_iterator& bitpos, const std::vector<bool>::const_iterator& endpos)
+uint32_t DecodeMatch(size_t& bitpos, const std::span<const std::byte>& data)
 {
-    return DecodeBits(bitpos, endpos, 2, MATCH_BIT_SIZES);
+    return DecodeBits(bitpos, data, 2, MATCH_BIT_SIZES);
 }
 
 
 const std::vector<uint8_t> JUMP_BIT_SIZES{5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20, 21, 22, 23, 24, 25, 26, 27, 28, 29, 30};
-uint32_t DecodeJump(std::vector<bool>::const_iterator& bitpos, const std::vector<bool>::const_iterator& endpos)
+uint32_t DecodeJump(size_t& bitpos, const std::span<const std::byte>& data)
 {
-    return DecodeBits(bitpos, endpos, 17, JUMP_BIT_SIZES);
+    return DecodeBits(bitpos, data, 17, JUMP_BIT_SIZES);
 }
 
 }
 
-uint32_t Interpret(const std::vector<bool> &asmap, const std::vector<bool> &ip)
+uint32_t Interpret(const std::span<const std::byte>& asmap, const std::span<const std::byte>& ip)
 {
-    std::vector<bool>::const_iterator pos = asmap.begin();
+    size_t pos{0};
-    const std::vector<bool>::const_iterator endpos = asmap.end();
+    uint8_t bits = ip.size() * 8;
-    uint8_t bits = ip.size();
     uint32_t default_asn = 0;
     uint32_t jump, match, matchlen;
     Instruction opcode;
-    while (pos != endpos) {
+    while (pos < asmap.size() * 8) {
-        opcode = DecodeType(pos, endpos);
+        opcode = DecodeType(pos, asmap);
         if (opcode == Instruction::RETURN) {
-            default_asn = DecodeASN(pos, endpos);
+            default_asn = DecodeASN(pos, asmap);
             if (default_asn == INVALID) break; // ASN straddles EOF
             return default_asn;
         } else if (opcode == Instruction::JUMP) {
-            jump = DecodeJump(pos, endpos);
+            jump = DecodeJump(pos, asmap);
             if (jump == INVALID) break; // Jump offset straddles EOF
             if (bits == 0) break; // No input bits left
-            if (int64_t{jump} >= int64_t{endpos - pos}) break; // Jumping past EOF
+            if (int64_t{jump} >= static_cast<int64_t>(asmap.size() * 8 - pos)) break; // Jumping past EOF
-            if (ip[ip.size() - bits]) {
+            if ((std::to_integer<uint8_t>(ip[(ip.size() * 8 - bits) / 8]) >> (7 - ((ip.size() * 8 - bits) % 8))) & 1) {
                 pos += jump;
             }
             bits--;
         } else if (opcode == Instruction::MATCH) {
-            match = DecodeMatch(pos, endpos);
+            match = DecodeMatch(pos, asmap);
             if (match == INVALID) break; // Match bits straddle EOF
             matchlen = std::bit_width(match) - 1;
             if (bits < matchlen) break; // Not enough input bits
             for (uint32_t bit = 0; bit < matchlen; bit++) {
-                if ((ip[ip.size() - bits]) != ((match >> (matchlen - 1 - bit)) & 1)) {
+                if (((std::to_integer<uint8_t>(ip[(ip.size() * 8 - bits) / 8]) >> (7 - ((ip.size() * 8 - bits) % 8))) & 1) != ((match >> (matchlen - 1 - bit)) & 1)) {
                     return default_asn;
                 }
                 bits--;
             }
         } else if (opcode == Instruction::DEFAULT) {
-            default_asn = DecodeASN(pos, endpos);
+            default_asn = DecodeASN(pos, asmap);
             if (default_asn == INVALID) break; // ASN straddles EOF
         } else {
             break; // Instruction straddles EOF
@@ -130,50 +130,48 @@ uint32_t Interpret(const std::vector<bool> &asmap, const std::vector<bool> &ip)
     return 0; // 0 is not a valid ASN
 }
 
-bool SanityCheckASMap(const std::vector<bool>& asmap, int bits)
+bool SanityCheckASMap(const std::span<const std::byte>& asmap, int bits)
 {
-    const std::vector<bool>::const_iterator begin = asmap.begin(), endpos = asmap.end();
+    size_t pos{0};
-    std::vector<bool>::const_iterator pos = begin;
+    size_t endpos{asmap.size() * 8};
     std::vector<std::pair<uint32_t, int>> jumps; // All future positions we may jump to (bit offset in asmap -> bits to consume left)
     jumps.reserve(bits);
     Instruction prevopcode = Instruction::JUMP;
     bool had_incomplete_match = false;
     while (pos != endpos) {
-        uint32_t offset = pos - begin;
+        if (!jumps.empty() && pos >= jumps.back().first) return false; // There was a jump into the middle of the previous instruction
-        if (!jumps.empty() && offset >= jumps.back().first) return false; // There was a jump into the middle of the previous instruction
+        Instruction opcode = DecodeType(pos, asmap);
-        Instruction opcode = DecodeType(pos, endpos);
         if (opcode == Instruction::RETURN) {
             if (prevopcode == Instruction::DEFAULT) return false; // There should not be any RETURN immediately after a DEFAULT (could be combined into just RETURN)
-            uint32_t asn = DecodeASN(pos, endpos);
+            uint32_t asn = DecodeASN(pos, asmap);
             if (asn == INVALID) return false; // ASN straddles EOF
             if (jumps.empty()) {
                 // Nothing to execute anymore
                 if (endpos - pos > 7) return false; // Excessive padding
                 while (pos != endpos) {
-                    if (*pos) return false; // Nonzero padding bit
+                    if ((std::to_integer<uint8_t>(asmap[pos / 8]) >> (pos % 8)) & 1) return false; // Nonzero padding bit
                     ++pos;
                 }
                 return true; // Sanely reached EOF
             } else {
                 // Continue by pretending we jumped to the next instruction
-                offset = pos - begin;
+                if (pos != jumps.back().first) return false; // Unreachable code
-                if (offset != jumps.back().first) return false; // Unreachable code
                 bits = jumps.back().second; // Restore the number of bits we would have had left after this jump
                 jumps.pop_back();
                 prevopcode = Instruction::JUMP;
             }
         } else if (opcode == Instruction::JUMP) {
-            uint32_t jump = DecodeJump(pos, endpos);
+            uint32_t jump = DecodeJump(pos, asmap);
             if (jump == INVALID) return false; // Jump offset straddles EOF
-            if (int64_t{jump} > int64_t{endpos - pos}) return false; // Jump out of range
+            if (int64_t{jump} > static_cast<int64_t>(endpos - pos)) return false; // Jump out of range
             if (bits == 0) return false; // Consuming bits past the end of the input
             --bits;
-            uint32_t jump_offset = pos - begin + jump;
+            uint32_t jump_offset = pos + jump;
             if (!jumps.empty() && jump_offset >= jumps.back().first) return false; // Intersecting jumps
             jumps.emplace_back(jump_offset, bits);
             prevopcode = Instruction::JUMP;
         } else if (opcode == Instruction::MATCH) {
-            uint32_t match = DecodeMatch(pos, endpos);
+            uint32_t match = DecodeMatch(pos, asmap);
             if (match == INVALID) return false; // Match bits straddle EOF
             int matchlen = std::bit_width(match) - 1;
             if (prevopcode != Instruction::MATCH) had_incomplete_match = false;
@@ -184,7 +182,7 @@ bool SanityCheckASMap(const std::vector<bool>& asmap, int bits)
             prevopcode = Instruction::MATCH;
         } else if (opcode == Instruction::DEFAULT) {
             if (prevopcode == Instruction::DEFAULT) return false; // There should not be two successive DEFAULTs (they could be combined into one)
-            uint32_t asn = DecodeASN(pos, endpos);
+            uint32_t asn = DecodeASN(pos, asmap);
             if (asn == INVALID) return false; // ASN straddles EOF
             prevopcode = Instruction::DEFAULT;
         } else {
@@ -194,30 +192,46 @@ bool SanityCheckASMap(const std::vector<bool>& asmap, int bits)
     return false; // Reached EOF without RETURN instruction
 }
 
-std::vector<bool> DecodeAsmap(fs::path path)
+std::span<const std::byte> CheckAsmap(const std::span<const std::byte>& data)
+{
+    if (data.empty()) {
+        return {};
+    }
+    if (!SanityCheckASMap(data, 128)) {
+        LogInfo("Sanity check of asmap data failed\n");
+        return {};
+    }
+    return data;
+}
+
+std::vector<std::byte> DecodeAsmap(fs::path path)
 {
-    std::vector<bool> bits;
     FILE *filestr = fsbridge::fopen(path, "rb");
     AutoFile file{filestr};
     if (file.IsNull()) {
-        LogPrintf("Failed to open asmap file from disk\n");
+        LogInfo("Failed to open asmap file from disk\n");
-        return bits;
-    }
-    file.seek(0, SEEK_END);
-    int length = file.tell();
-    LogPrintf("Opened asmap file %s (%d bytes) from disk\n", fs::quoted(fs::PathToString(path)), length);
-    file.seek(0, SEEK_SET);
-    uint8_t cur_byte;
-    for (int i = 0; i < length; ++i) {
-        file >> cur_byte;
-        for (int bit = 0; bit < 8; ++bit) {
-            bits.push_back((cur_byte >> bit) & 1);
-        }
-    }
-    if (!SanityCheckASMap(bits, 128)) {
-        LogPrintf("Sanity check of asmap file %s failed\n", fs::quoted(fs::PathToString(path)));
         return {};
     }
-    return bits;
+
+    file.seek(0, SEEK_END);
+    int length = file.tell();
+    LogInfo("Opened asmap file %s (%d bytes) from disk\n", fs::quoted(fs::PathToString(path)), length);
+    file.seek(0, SEEK_SET);
+
+    std::vector<std::byte> buffer(length);
+    file.read(buffer);
+
+    if (!SanityCheckASMap(buffer, 128)) {
+        LogInfo("Sanity check of asmap data failed\n");
+        return {};
+    }
+
+    return buffer;
 }
 
+uint256 AsmapChecksum(const std::span<const std::byte>& data)
+{
+    HashWriter asmap_hasher;
+    asmap_hasher << data;
+    return asmap_hasher.GetHash();
+}

src/util/asmap.h

@@ -5,16 +5,22 @@
 #ifndef BITCOIN_UTIL_ASMAP_H
 #define BITCOIN_UTIL_ASMAP_H
 
+#include <uint256.h>
 #include <util/fs.h>
 
 #include <cstdint>
+#include <span>
 #include <vector>
 
-uint32_t Interpret(const std::vector<bool> &asmap, const std::vector<bool> &ip);
+uint32_t Interpret(const std::span<const std::byte>& asmap, const std::span<const std::byte>& ip);
 
-bool SanityCheckASMap(const std::vector<bool>& asmap, int bits);
+bool SanityCheckASMap(const std::span<const std::byte>& asmap, int bits);
 
-/** Read asmap from provided binary file */
+/** Read and check asmap from provided binary file */
-std::vector<bool> DecodeAsmap(fs::path path);
+std::vector<std::byte> DecodeAsmap(fs::path path);
+/** Check asmap from embedded data */
+std::span<const std::byte> CheckAsmap(const std::span<const std::byte>& data);
+/** Calculate asmap checksum */
+uint256 AsmapChecksum(const std::span<const std::byte>& data);
 
 #endif // BITCOIN_UTIL_ASMAP_H

test/functional/feature_asmap.py

@@ -31,7 +31,7 @@ from test_framework.util import assert_equal
 
 DEFAULT_ASMAP_FILENAME = 'ip_asn.map' # defined in src/init.cpp
 ASMAP = 'src/test/data/asmap.raw' # path to unit test skeleton asmap
-VERSION = 'fec61fa21a9f46f3b17bdcd660d7f4cd90b966aad3aec593c99b35f0aca15853'
+VERSION = 'bafc9da308f45179443bd1d22325400ac9104f741522d003e3fac86700f68895'
 
 def expected_messages(filename):
     return [f'Opened asmap file "{filename}" (59 bytes) from disk',