initial commit

2026-04-21 11:01:03 +02:00
commit e9a527b5de
19 changed files with 12675 additions and 0 deletions
@@ -0,0 +1,374 @@
+
+extern "C" {
+#include <unistd.h>
+#include <fcntl.h>
+#include <sys/ioctl.h>
+#include <net/if.h>
+#include <linux/if.h>
+#include <linux/if_tun.h>
+
+#include <sys/socket.h>
+#include <netinet/in.h>
+
+#include <arpa/inet.h>
+#include <linux/netlink.h>
+#include <linux/rtnetlink.h>
+}
+
+#include <cstring>
+#include <expected>
+#include <string>
+#include <vector>
+#include <span>
+#include <iostream>
+#include <thread>
+#include <chrono>
+
+#include <tunnel.hpp>
+
+std::expected<void, std::string> Interface::Create(const std::string name) {
+        if ((tunfd = open("/dev/net/tun", O_RDWR | O_CLOEXEC)) < 0) {
+                int errnocopy = errno;
+                std::string error = std::strerror(errnocopy);
+                return std::unexpected("Create interface error: " + error);
+        }
+        struct ifreq ifr;
+        memset(&ifr, 0, sizeof(ifr));
+        ifr.ifr_flags = IFF_TUN | IFF_NO_PI;
+        strncpy(ifr.ifr_name, name.c_str(), IFNAMSIZ - 1);
+        if (ioctl(tunfd, TUNSETIFF, (void*)(&ifr)) < 0) {
+                close(tunfd);
+                int errnocopy = errno;
+                std::string error = std::strerror(errnocopy);
+                return std::unexpected("Create interface error: " + error);
+        }
+        ifname = ifr.ifr_name;
+#if 0
+        if (ioctl(tunfd, TUNSETPERSIST, 0) < 0) {
+                close(tunfd);
+                int errnocopy = errno;
+                std::string error = std::strerror(errnocopy);
+                return std::unexpected("Create interface error: " + error);
+        }
+#endif
+
+        //struct ifreq ifr;
+        memset(&ifr, 0, sizeof(ifr));
+        int sockfd = 0;
+        if ((sockfd = socket(AF_INET, SOCK_DGRAM, 0)) < 0) {
+                close(tunfd);
+                int errnocopy = errno;
+                std::string error = std::strerror(errnocopy);
+                return std::unexpected("Get MTU error: " + error);
+        }
+        strncpy(ifr.ifr_name, ifname.c_str(), IFNAMSIZ - 1);
+        if (ioctl(sockfd, SIOCGIFMTU, &ifr) < 0) {
+                close(tunfd);
+                close(sockfd);
+                int errnocopy = errno;
+                std::string error = std::strerror(errnocopy);
+                return std::unexpected("Get MTU error: " + error);
+        }
+        close(sockfd);
+        mtu = ifr.ifr_mtu;
+        return {};
+}
+
+std::expected<void, std::string> Interface::SetMTU(int ifmtu) {
+        int sockfd = 0;
+        if ((sockfd = socket(AF_INET, SOCK_DGRAM, 0)) < 0) {
+                int errnocopy = errno;
+                std::string error = std::strerror(errnocopy);
+                return std::unexpected("Set MTU error: " + error);
+        }
+        struct ifreq ifr;
+        memset(&ifr, 0, sizeof(ifr));
+        strncpy(ifr.ifr_name, ifname.c_str(), IFNAMSIZ - 1);
+        ifr.ifr_mtu = ifmtu;
+        if (ioctl(sockfd, SIOCSIFMTU, &ifr) < 0) {
+                close(sockfd);
+                int errnocopy = errno;
+                std::string error = std::strerror(errnocopy);
+                return std::unexpected("Set MTU error: " + error);
+        }
+        close(sockfd);
+        return {};
+}
+
+std::expected<int, std::string> Interface::GetMTU(void) {
+        struct ifreq ifr;
+        memset(&ifr, 0, sizeof(ifr));
+        int sockfd = 0;
+        if ((sockfd = socket(AF_INET, SOCK_DGRAM, 0)) < 0) {
+                int errnocopy = errno;
+                std::string error = std::strerror(errnocopy);
+                return std::unexpected("Get MTU error: " + error);
+        }
+        strncpy(ifr.ifr_name, ifname.c_str(), IFNAMSIZ - 1);
+        if (ioctl(sockfd, SIOCGIFMTU, &ifr) < 0) {
+                close(sockfd);
+                int errnocopy = errno;
+                std::string error = std::strerror(errnocopy);
+                return std::unexpected("Get MTU error: " + error);
+        }
+        close(sockfd);
+        return ifr.ifr_mtu;
+}
+
+std::expected<std::string, std::string> Interface::GetIP4Address(void) {
+        struct ifreq ifr;
+        memset(&ifr, 0, sizeof(ifr));
+        int sockfd = 0;
+        if ((sockfd = socket(AF_INET, SOCK_DGRAM, 0)) < 0) {
+                int errnocopy = errno;
+                std::string error = std::strerror(errnocopy);
+                return std::unexpected("Get MTU error: " + error);
+        }
+        ifr.ifr_addr.sa_family = AF_INET;
+        strncpy(ifr.ifr_name, ifname.c_str(), IFNAMSIZ - 1);
+
+        if (ioctl(sockfd, SIOCGIFADDR, &ifr) < 0) {
+                close(sockfd);
+                int errnocopy = errno;
+                std::string error = std::strerror(errnocopy);
+                return std::unexpected("Get MTU error: " + error);
+        }
+        close(sockfd);
+
+        auto sinaddr = ((struct sockaddr_in *)&ifr.ifr_addr)->sin_addr;
+        std::string addr = inet_ntoa(sinaddr);
+        return addr;
+}
+
+std::expected<void, std::string> Interface::SetIP4Address(std::string ipaddr) {
+        struct ifreq ifr;
+        memset(&ifr, 0, sizeof(ifr));
+        int sockfd = 0;
+        if ((sockfd = socket(AF_INET, SOCK_DGRAM, 0)) < 0) {
+                int errnocopy = errno;
+                std::string error = std::strerror(errnocopy);
+                return std::unexpected("Set address error: " + error);
+        }
+        ifr.ifr_addr.sa_family = AF_INET;
+        strncpy(ifr.ifr_name, ifname.c_str(), IFNAMSIZ - 1);
+
+        struct sockaddr_in* addr = (struct sockaddr_in *)&ifr.ifr_addr;
+        addr->sin_family = AF_INET;
+        if (inet_pton(AF_INET, ipaddr.c_str(), &addr->sin_addr) <= 0) {
+                close(sockfd);
+                int errnocopy = errno;
+                std::string error = std::strerror(errnocopy);
+                return std::unexpected("Set address error: " + error);
+        }
+        if (ioctl(sockfd, SIOCSIFADDR, &ifr) < 0) {
+                close(sockfd);
+                int errnocopy = errno;
+                std::string error = std::strerror(errnocopy);
+                return std::unexpected("Set address error: " + error);
+        }
+        close(sockfd);
+        return {};
+}
+
+std::expected<void, std::string> Interface::SetIP4Netmask(int prefix) {
+        if (prefix < 0 || prefix > 32) {
+                return std::unexpected("Invalid prefix");
+        }
+        uint32_t mask = (prefix == 0) ? 0 : (~0U << (32 - prefix));
+
+        struct in_addr maskaddr;
+        maskaddr.s_addr = htonl(mask);
+        char buffer[INET_ADDRSTRLEN];
+        if (inet_ntop(AF_INET, &maskaddr, buffer, sizeof(buffer)) == NULL) {
+                int errnocopy = errno;
+                std::string error = std::strerror(errnocopy);
+                return std::unexpected("Set1 netmask error: " + error);
+        }
+        auto netmask = std::string(buffer);
+
+        struct ifreq ifr;
+        memset(&ifr, 0, sizeof(ifr));
+        int sockfd = 0;
+        if ((sockfd = socket(AF_INET, SOCK_DGRAM, 0)) < 0) {
+                int errnocopy = errno;
+                std::string error = std::strerror(errnocopy);
+                return std::unexpected("Set2 netmask error: " + error);
+        }
+        ifr.ifr_addr.sa_family = AF_INET;
+        strncpy(ifr.ifr_name, ifname.c_str(), IFNAMSIZ - 1);
+
+        struct sockaddr_in* addr = (struct sockaddr_in *)&ifr.ifr_addr;
+        addr->sin_family = AF_INET;
+        if (inet_pton(AF_INET, netmask.c_str(), &addr->sin_addr) < 0) {
+                close(sockfd);
+                int errnocopy = errno;
+                std::string error = std::strerror(errnocopy);
+                return std::unexpected("Set3 netmask error: " + error);
+        }
+        if (ioctl(sockfd, SIOCSIFNETMASK, &ifr) < 0) {
+                close(sockfd);
+                int errnocopy = errno;
+                std::string error = std::strerror(errnocopy);
+                return std::unexpected("Set4 netmask error: " + error);
+        }
+        close(sockfd);
+        return {};
+}
+
+std::expected<void, std::string> Interface::Up(void) {
+        int sockfd = 0;
+        if ((sockfd = socket(AF_INET, SOCK_DGRAM, 0)) < 0) {
+                int errnocopy = errno;
+                std::string error = std::strerror(errnocopy);
+                return std::unexpected("Up interface error: " + error);
+        }
+
+        struct ifreq ifr;
+        memset(&ifr, 0, sizeof(ifr));
+        strncpy(ifr.ifr_name, ifname.c_str(), IFNAMSIZ - 1);
+        if (ioctl(sockfd, SIOCGIFFLAGS, &ifr) < 0) {
+                close(sockfd);
+                int errnocopy = errno;
+                std::string error = std::strerror(errnocopy);
+                return std::unexpected("Up interface error: " + error);
+        }
+        ifr.ifr_flags |= (IFF_UP | IFF_RUNNING);
+        if (ioctl(sockfd, SIOCSIFFLAGS, &ifr) < 0) {
+                close(sockfd);
+                int errnocopy = errno;
+                std::string error = std::strerror(errnocopy);
+                return std::unexpected("Up interface error: " + error);
+        }
+        close(sockfd);
+        return {};
+}
+
+std::expected<void, std::string> Interface::Down(void) {
+        int sockfd = 0;
+        if ((sockfd = socket(AF_INET, SOCK_DGRAM, 0)) < 0) {
+                int errnocopy = errno;
+                std::string error = std::strerror(errnocopy);
+                return std::unexpected("Up interface error: " + error);
+        }
+        struct ifreq ifr;
+        memset(&ifr, 0, sizeof(ifr));
+        strncpy(ifr.ifr_name, ifname.c_str(), IFNAMSIZ - 1);
+        if (ioctl(sockfd, SIOCGIFFLAGS, &ifr) < 0) {
+                close(sockfd);
+                int errnocopy = errno;
+                std::string error = std::strerror(errnocopy);
+                return std::unexpected("Up interface error: " + error);
+        }
+        ifr.ifr_flags &= ~IFF_UP;
+        if (ioctl(sockfd, SIOCSIFFLAGS, &ifr) < 0) {
+                close(sockfd);
+                int errnocopy = errno;
+                std::string error = std::strerror(errnocopy);
+                return std::unexpected("Up interface error: " + error);
+        }
+        close(sockfd);
+        return {};
+}
+
+std::string Interface::Name() {
+        return ifname;
+}
+
+int Interface::MTU() {
+        return mtu;
+}
+
+Interface::~Interface() {
+        close(tunfd);
+}
+
+std::expected<void, std::string> Interface::UpN(void) {
+        int netlinkfd = 0;
+	if ((netlinkfd = socket(AF_NETLINK, SOCK_RAW | SOCK_CLOEXEC, NETLINK_ROUTE)) < 0) {
+                int errnocopy = errno;
+                std::string error = std::strerror(errnocopy);
+                return std::unexpected("Create interface error: " + error);
+        }
+
+	struct {
+		struct nlmsghdr  header;
+		struct ifinfomsg content;
+	} request;
+
+	memset(&request, 0, sizeof request);
+	request.header.nlmsg_len = NLMSG_LENGTH(sizeof request.content);
+	request.header.nlmsg_flags = NLM_F_REQUEST;
+	request.header.nlmsg_type = RTM_NEWLINK;
+	request.content.ifi_index = if_nametoindex(ifname.c_str());
+	request.content.ifi_flags = IFF_UP;
+	request.content.ifi_change = 1;
+
+	if (send(netlinkfd, &request, request.header.nlmsg_len, 0) < 0) {
+                close(netlinkfd);
+                int errnocopy = errno;
+                std::string error = std::strerror(errnocopy);
+                return std::unexpected("Up interface error: " + error);
+        }
+        close(netlinkfd);
+        return {};
+}
+
+
+std::expected<void, std::string> Interface::SetIP4AddrMask(const std::string address, const int prefix) {
+        int netlinkfd = 0;
+	if ((netlinkfd = socket(AF_NETLINK, SOCK_RAW | SOCK_CLOEXEC, NETLINK_ROUTE)) < 0) {
+                int errnocopy = errno;
+                std::string error = std::strerror(errnocopy);
+                return std::unexpected("Create interface error: " + error);
+        }
+
+        int rc = 0;
+        struct sockaddr_nl sockaddr;
+	memset(&sockaddr, 0, sizeof sockaddr);
+	sockaddr.nl_family = AF_NETLINK;
+	if ((rc = bind(netlinkfd, (struct sockaddr*) &sockaddr, sizeof sockaddr))< 0) {
+                close(netlinkfd);
+                int errnocopy = errno;
+                std::string error = std::strerror(errnocopy);
+                return std::unexpected("Set interface address error: " + error);
+        }
+        struct {
+		struct nlmsghdr  header;
+		struct ifaddrmsg content;
+		char             attributes_buf[64];
+	} request;
+
+	struct rtattr *request_attr;
+	size_t attributes_buf_avail = sizeof request.attributes_buf;
+
+	memset(&request, 0, sizeof request);
+	request.header.nlmsg_len = NLMSG_LENGTH(sizeof request.content);
+	request.header.nlmsg_flags = NLM_F_REQUEST | NLM_F_EXCL | NLM_F_CREATE;
+	request.header.nlmsg_type = RTM_NEWADDR;
+	request.content.ifa_index = if_nametoindex(ifname.c_str());
+	request.content.ifa_family = AF_INET;
+	request.content.ifa_prefixlen = prefix;
+
+	/* request.attributes[IFA_LOCAL] = address */
+	request_attr = IFA_RTA(&request.content);
+	request_attr->rta_type = IFA_LOCAL;
+	request_attr->rta_len = RTA_LENGTH(sizeof (struct in_addr));
+	request.header.nlmsg_len += request_attr->rta_len;
+	inet_pton(AF_INET, address.c_str(), RTA_DATA(request_attr));
+
+	/* request.attributes[IFA_ADDRESS] = address */
+	request_attr = RTA_NEXT(request_attr, attributes_buf_avail);
+	request_attr->rta_type = IFA_ADDRESS;
+	request_attr->rta_len = RTA_LENGTH(sizeof (struct in_addr));
+	request.header.nlmsg_len += request_attr->rta_len;
+	inet_pton(AF_INET, address.c_str(), RTA_DATA(request_attr));
+
+	if (send(netlinkfd, &request, request.header.nlmsg_len, 0) < 0) {
+                close(netlinkfd);
+                int errnocopy = errno;
+                std::string error = std::strerror(errnocopy);
+                return std::unexpected("Set interface address error: " + error);
+        }
+        close(netlinkfd);
+        return {};
+}