From 879481feab5ccaf12ca48cd46f58fd03839571b9 Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?=D0=9E=D0=BB=D0=B5=D0=B3=20=D0=91=D0=BE=D1=80=D0=BE=D0=B4?=
 =?UTF-8?q?=D0=B8=D0=BD?= <onborodin@gmail.com>
Date: Thu, 7 May 2026 17:53:17 +0200
Subject: [PATCH] working commit

---
 works/iprange.c           | 39 ++++++++++++++++++++++
 works/iprange.cpp         | 70 +++++++++++++++++++++++++++++++++++++++
 works/iprouter_w_list.cpp |  2 +-
 3 files changed, 110 insertions(+), 1 deletion(-)
 create mode 100644 works/iprange.c
 create mode 100644 works/iprange.cpp

diff --git a/works/iprange.c b/works/iprange.c
new file mode 100644
index 0000000..c80005e
--- /dev/null
+++ b/works/iprange.c
@@ -0,0 +1,39 @@
+#include <stdio.h>
+#include <arpa/inet.h>
+
+void network4(const char* network, int prefix) {
+        struct in_addr inaddr;
+        // Convert from human view to network bytes
+        if (inet_pton(AF_INET, network, &inaddr) == 0) {
+                printf("Invalid IP address\n");
+                return;
+        }
+        // Convert from network bytes to local
+        uint32_t ip = ntohl(inaddr.s_addr);
+
+        // Calculate mask and net
+        uint32_t mask = (prefix == 0) ? 0 : (~0U << (32 - prefix));
+        uint32_t net = ip & mask;
+        uint32_t fip = net + 1;
+
+        // Convert net address bytes to network order
+        struct in_addr net_addr;
+        net_addr.s_addr = htonl(net);
+        // Convert mask bytes to network order
+        struct in_addr mask_addr;
+        mask_addr.s_addr = htonl(mask);
+        // Convert mask bytes to network order
+        struct in_addr fip_addr;
+        fip_addr.s_addr = htonl(fip);
+
+        printf("IP:      %s/%d\n", network, prefix);
+        printf("Netmask: %s\n", inet_ntoa(mask_addr));
+        printf("Network: %s\n", inet_ntoa(net_addr));
+        printf("First:   %s\n", inet_ntoa(fip_addr));
+}
+
+int main() {
+        network4("192.168.1.154", 26);
+        return 0;
+}
+
diff --git a/works/iprange.cpp b/works/iprange.cpp
new file mode 100644
index 0000000..12a5601
--- /dev/null
+++ b/works/iprange.cpp
@@ -0,0 +1,70 @@
+
+extern "C" {
+#include <stdio.h>
+#include <arpa/inet.h>
+}
+
+#include <format>
+#include <expected>
+#include <string>
+#include <ostream>
+#include <iostream>
+
+std::expected<std::string, std::string> network6(std::string network, int prefix) {
+        struct in6_addr addr;
+        unsigned char mask[16] = {0};
+        if (inet_pton(AF_INET6, network.data(), &addr) != 1) {
+                return std::unexpected(std::format("Invalid network address {}", network));
+        }
+        for (int i = 0; i < prefix; i++) {
+                mask[i / 8] |= (1 << (7 - (i % 8)));
+        }
+        for (int i = 0; i < 16; i++) {
+                addr.s6_addr[i] &= mask[i];
+        }
+
+        uint64_t *host_part = (uint64_t *)&addr.s6_addr[8];
+        uint64_t hostnum = be64toh(*host_part);
+        hostnum += 2;
+        *host_part = htobe64(hostnum);
+
+        char buffer[INET6_ADDRSTRLEN] = {'\0'};
+        inet_ntop(AF_INET6, &addr, buffer, INET6_ADDRSTRLEN);
+
+        return std::string(buffer);
+}
+
+
+std::expected<std::string, std::string> network4(std::string network, int prefix) {
+        struct in_addr inaddr;
+        if (inet_pton(AF_INET, network.data(), &inaddr) != 1) {
+                return std::unexpected(std::format("Invalid network address {}", network));
+        }
+        uint32_t ip = ntohl(inaddr.s_addr);
+        uint32_t mask = (prefix == 0) ? 0 : (~0U << (32 - prefix));
+        uint32_t fip = (ip & mask) + 1;
+        struct in_addr ip_addr;
+        ip_addr.s_addr = htonl(ip);
+
+        return std::string(inet_ntoa(ip_addr));
+}
+
+int main() {
+        auto net4Res = network4("192.168.1.154", 26);
+        if (!net4Res) {
+                std::cerr << net4Res.error() << std::endl;
+                return 1;
+        }
+        std::cout << net4Res.value() << std::endl;
+
+        auto net6Res = network6("2001:db8:abcd:1234::0", 64);
+        if (!net6Res) {
+                std::cerr << net6Res.error() << std::endl;
+                return 1;
+        }
+        std::cout << net6Res.value() << std::endl;
+
+
+        return 0;
+}
+
diff --git a/works/iprouter_w_list.cpp b/works/iprouter_w_list.cpp
index 7c510de..1535d25 100644
--- a/works/iprouter_w_list.cpp
+++ b/works/iprouter_w_list.cpp
@@ -34,7 +34,7 @@ std::expected<void, std::string> Router::AddRoute(std::string address, uint64_t
         struct sockaddr_in *sin;
         sin = (struct sockaddr_in*)&rt.rt_dst;
         sin->sin_family = AF_INET;
-        if (inet_pton(AF_INET, address.data(), &sin->sin_addr) != 1){
+        if (inet_pton(AF_INET, address.data(), &sin->sin_addr) != 1) {
                 int errnoCopy = errno;
                 std::string error = std::strerror(errnoCopy);
                 return std::unexpected(std::format("Incorrect address {}, error: {}", address, error));