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diff --git a/src/common/pcp.h b/src/common/pcp.h
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+// Copyright (c) 2024 The Bitcoin Core developers
+// Distributed under the MIT software license, see the accompanying
+// file COPYING or https://www.opensource.org/licenses/mit-license.php.
+
+#ifndef BITCOIN_COMMON_PCP_H
+#define BITCOIN_COMMON_PCP_H
+
+#include <netaddress.h>
+
+#include <variant>
+
+// RFC6886 NAT-PMP and RFC6887 Port Control Protocol (PCP) implementation.
+// NAT-PMP and PCP use network byte order (big-endian).
+
+//! Mapping nonce size in bytes (see RFC6887 section 11.1).
+constexpr size_t PCP_MAP_NONCE_SIZE = 12;
+
+//! PCP mapping nonce. Arbitrary data chosen by the client to identify a mapping.
+typedef std::array<uint8_t, PCP_MAP_NONCE_SIZE> PCPMappingNonce;
+
+//! Unsuccessful response to a port mapping.
+enum class MappingError {
+    NETWORK_ERROR,  ///< Any kind of network-level error.
+    PROTOCOL_ERROR, ///< Any kind of protocol-level error, except unsupported version or no resources.
+    UNSUPP_VERSION, ///< Unsupported protocol version.
+    NO_RESOURCES,   ///< No resources available (port probably already mapped).
+};
+
+//! Successful response to a port mapping.
+struct MappingResult {
+    MappingResult(uint8_t version, const CService &internal_in, const CService &external_in, uint32_t lifetime_in):
+        version(version), internal(internal_in), external(external_in), lifetime(lifetime_in) {}
+    //! Protocol version, one of NATPMP_VERSION or PCP_VERSION.
+    uint8_t version;
+    //! Internal host:port.
+    CService internal;
+    //! External host:port.
+    CService external;
+    //! Granted lifetime of binding (seconds).
+    uint32_t lifetime;
+
+    //! Format mapping as string for logging.
+    std::string ToString();
+};
+
+//! Try to open a port using RFC 6886 NAT-PMP. IPv4 only.
+//!
+//! * gateway: Destination address for PCP requests (usually the default gateway).
+//! * port: Internal port, and desired external port.
+//! * lifetime: Requested lifetime in seconds for mapping. The server may assign as shorter or longer lifetime. A lifetime of 0 deletes the mapping.
+//! * num_tries: Number of tries in case of no response.
+//!
+//! Returns the external_ip:external_port of the mapping if successful, otherwise a MappingError.
+std::variant<MappingResult, MappingError> NATPMPRequestPortMap(const CNetAddr &gateway, uint16_t port, uint32_t lifetime, int num_tries = 3, std::chrono::milliseconds timeout_per_try = std::chrono::milliseconds(1000));
+
+//! Try to open a port using RFC 6887 Port Control Protocol (PCP). Handles IPv4 and IPv6.
+//!
+//! * nonce: Mapping cookie. Keep this the same over renewals.
+//! * gateway: Destination address for PCP requests (usually the default gateway).
+//! * bind: Specific local bind address for IPv6 pinholing. Set this as INADDR_ANY for IPv4.
+//! * port: Internal port, and desired external port.
+//! * lifetime: Requested lifetime in seconds for mapping. The server may assign as shorter or longer lifetime. A lifetime of 0 deletes the mapping.
+//! * num_tries: Number of tries in case of no response.
+//!
+//! Returns the external_ip:external_port of the mapping if successful, otherwise a MappingError.
+std::variant<MappingResult, MappingError> PCPRequestPortMap(const PCPMappingNonce &nonce, const CNetAddr &gateway, const CNetAddr &bind, uint16_t port, uint32_t lifetime, int num_tries = 3, std::chrono::milliseconds timeout_per_try = std::chrono::milliseconds(1000));
+
+#endif // BITCOIN_COMMON_PCP_H