Proxy.h

 
//
// Copyright (c) 2025, Isode Limited, London, England.
// All rights reserved.
// 
// Acquisition and use of this software and related materials for any
// purpose requires a written licence agreement from Isode
// Limited, or a written licence from an organisation licenced by Isode
// Limited to grant such a licence.
//
#pragma once
 
#if defined(_WIN32)
#include <ws2tcpip.h>
#else
#include <arpa/inet.h>
#endif
 
#include <cstdint>
#include <cstddef>
#include <cstring>
#include <string>
 
namespace Stream {
    // Type for a function (or closure) reading some data
    using ReadFunction = size_t (*)(char *, size_t);
 
    struct ipv4_addr{        /* for TCP/UDP over IPv4, len = 12 */
        std::uint32_t src_addr;
        std::uint32_t dst_addr;
        std::uint16_t src_port;
        std::uint16_t dst_port;
    };
    struct ipv6_addr {        /* for TCP/UDP over IPv6, len = 36 */
        in6_addr      src_addr;
        in6_addr      dst_addr;
        std::uint16_t src_port;
        std::uint16_t dst_port;
    };
    bool read_proxy_ipv4(const std::string& addr, ipv4_addr &proxy_header);
    bool read_proxy_ipv6(const std::string& addr, ipv6_addr &proxy_header);
 
    struct proxy_hdr_v2 {
        std::uint8_t sig[12];  /* hex 0D 0A 0D 0A 00 0D 0A 51 55 49 54 0A */
        std::uint8_t ver_cmd;  /* protocol version and command */
        std::uint8_t fam;      /* protocol family and address */
        std::uint16_t len;     /* number of following bytes part of the header */
    };
 
    using string_iter = std::string::const_iterator;
    bool read_ipv4(string_iter& start, const string_iter end, std::uint32_t& addr);
    bool read_ipv6(string_iter& start, const string_iter end, in6_addr     & addr);
    bool read_port(string_iter& start, const string_iter end, std::uint16_t& port);
 
    const char v2sig[13] = "\x0D\x0A\x0D\x0A\x00\x0D\x0A\x51\x55\x49\x54\x0A";
}