Add extracted tools: CitrineOS, OpenOCPP, ShapeShifter

- CitrineOS core extracted (CSMS OCPP 2.0.1)
- OpenOCPP extracted (firmware OCPP 1.6J/2.0.1)
- ShapeShifter library installed (pip install -e)
- ShapeShifter specification extracted
- EVerest extracted

TODO updated with progress

tools/EVerest-main/modules/EVSE/EvseV2G/connection/connection.cpp

@@ -0,0 +1,691 @@
+// SPDX-License-Identifier: Apache-2.0
+// Copyright (C) 2022-2023 chargebyte GmbH
+// Copyright (C) 2022-2023 Contributors to EVerest
+
+#include "connection.hpp"
+#include "log.hpp"
+#include "tls_connection.hpp"
+#include "tools.hpp"
+#include "v2g_server.hpp"
+
+#include <generated/types/evse_manager.hpp>
+
+#include <arpa/inet.h>
+#include <cstring>
+#include <ctype.h>
+#include <dirent.h>
+#include <errno.h>
+#include <fstream>
+#include <inttypes.h>
+#include <iostream>
+#include <net/if.h>
+#include <netinet/in.h>
+#include <poll.h>
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+#include <string>
+#include <sys/socket.h>
+#include <time.h>
+#include <unistd.h>
+
+#define DEFAULT_SOCKET_BACKLOG        3
+#define DEFAULT_TCP_PORT              61341
+#define DEFAULT_TLS_PORT              64109
+#define ERROR_SESSION_ALREADY_STARTED 2
+#define CLIENT_FIN_TIMEOUT            3000
+
+/*!
+ * \brief connection_create_socket This function creates a tcp/tls socket
+ * \param sockaddr to bind the socket to an interface
+ * \return Returns \c 0 on success, otherwise \c -1
+ */
+static int connection_create_socket(struct sockaddr_in6* sockaddr) {
+    socklen_t addrlen = sizeof(*sockaddr);
+    int s, enable = 1;
+    static bool error_once = false;
+
+    /* create socket */
+    s = socket(AF_INET6, SOCK_STREAM, 0);
+    if (s == -1) {
+        if (!error_once) {
+            dlog(DLOG_LEVEL_ERROR, "socket() failed: %s", strerror(errno));
+            error_once = true;
+        }
+        return -1;
+    }
+
+    if (setsockopt(s, SOL_SOCKET, SO_REUSEPORT, &enable, sizeof(enable)) == -1) {
+        if (!error_once) {
+            dlog(DLOG_LEVEL_ERROR, "setsockopt(SO_REUSEPORT) failed: %s", strerror(errno));
+            error_once = true;
+        }
+        close(s);
+        return -1;
+    }
+
+    /* bind it to interface */
+    if (bind(s, reinterpret_cast<struct sockaddr*>(sockaddr), addrlen) == -1) {
+        if (!error_once) {
+            dlog(DLOG_LEVEL_WARNING, "bind() failed: %s", strerror(errno));
+            dlog(DLOG_LEVEL_WARNING,
+                 "Verify that the configured interface has a valid IPv6 link local address configured.");
+            error_once = true;
+        }
+        close(s);
+        return -1;
+    }
+
+    /* listen on this socket */
+    if (listen(s, DEFAULT_SOCKET_BACKLOG) == -1) {
+        if (!error_once) {
+            dlog(DLOG_LEVEL_ERROR, "listen() failed: %s", strerror(errno));
+            error_once = true;
+        }
+        close(s);
+        return -1;
+    }
+
+    /* retrieve the actual port number we are listening on */
+    if (getsockname(s, reinterpret_cast<struct sockaddr*>(sockaddr), &addrlen) == -1) {
+        if (!error_once) {
+            dlog(DLOG_LEVEL_ERROR, "getsockname() failed: %s", strerror(errno));
+            error_once = true;
+        }
+        close(s);
+        return -1;
+    }
+
+    return s;
+}
+
+/*!
+ * \brief check_interface This function checks the interface name. The interface name is
+ * configured automatically in case it is pre-initialized to “auto.
+ * \param sockaddr to bind the socket to an interface
+ * \return Returns \c 0 on success, otherwise \c -1
+ */
+int check_interface(struct v2g_context* v2g_ctx) {
+    if (v2g_ctx == nullptr || v2g_ctx->if_name == nullptr) {
+        return -1;
+    }
+
+    struct ipv6_mreq mreq = {};
+    std::memset(&mreq, 0, sizeof(mreq));
+
+    if (strcmp(v2g_ctx->if_name, "auto") == 0) {
+        v2g_ctx->if_name = choose_first_ipv6_interface();
+    }
+
+    if (v2g_ctx->if_name == nullptr) {
+        return -1;
+    }
+
+    mreq.ipv6mr_interface = if_nametoindex(v2g_ctx->if_name);
+    if (!mreq.ipv6mr_interface) {
+        dlog(DLOG_LEVEL_ERROR, "No such interface: %s", v2g_ctx->if_name);
+        return -1;
+    }
+
+    return (v2g_ctx->if_name == nullptr) ? -1 : 0;
+}
+
+/*!
+ * \brief connection_init This function initilizes the tcp and tls interface.
+ * \param v2g_context is the V2G context.
+ * \return Returns \c 0 on success, otherwise \c -1
+ */
+int connection_init(struct v2g_context* v2g_ctx) {
+    if (check_interface(v2g_ctx) == -1) {
+        return -1;
+    }
+
+    if (v2g_ctx->tls_security != TLS_SECURITY_FORCE) {
+        v2g_ctx->local_tcp_addr = static_cast<sockaddr_in6*>(calloc(1, sizeof(*v2g_ctx->local_tcp_addr)));
+        if (v2g_ctx->local_tcp_addr == nullptr) {
+            dlog(DLOG_LEVEL_ERROR, "Failed to allocate memory for TCP address");
+            return -1;
+        }
+    }
+
+    if (v2g_ctx->tls_security != TLS_SECURITY_PROHIBIT) {
+        v2g_ctx->local_tls_addr = static_cast<sockaddr_in6*>(calloc(1, sizeof(*v2g_ctx->local_tls_addr)));
+        if (!v2g_ctx->local_tls_addr) {
+            dlog(DLOG_LEVEL_ERROR, "Failed to allocate memory for TLS address");
+            return -1;
+        }
+    }
+
+    while (1) {
+        if (v2g_ctx->local_tcp_addr) {
+            get_interface_ipv6_address(v2g_ctx->if_name, ADDR6_TYPE_LINKLOCAL, v2g_ctx->local_tcp_addr);
+            if (v2g_ctx->local_tls_addr) {
+                // Handle allowing TCP with TLS (TLS_SECURITY_ALLOW)
+                memcpy(v2g_ctx->local_tls_addr, v2g_ctx->local_tcp_addr, sizeof(*v2g_ctx->local_tls_addr));
+            }
+        } else {
+            // Handle forcing TLS security (TLS_SECURITY_FORCE)
+            get_interface_ipv6_address(v2g_ctx->if_name, ADDR6_TYPE_LINKLOCAL, v2g_ctx->local_tls_addr);
+        }
+
+        if (v2g_ctx->local_tcp_addr) {
+            char buffer[INET6_ADDRSTRLEN];
+
+            /*
+             * When we bind with port = 0, the kernel assigns a dynamic port from the range configured
+             * in /proc/sys/net/ipv4/ip_local_port_range. This is on a recent Ubuntu Linux e.g.
+             * $ cat /proc/sys/net/ipv4/ip_local_port_range
+             * 32768   60999
+             * However, in ISO15118 spec the IANA range with 49152 to 65535 is referenced. So we have the
+             * problem that the kernel (without further configuration - and we want to avoid this) could
+             * hand out a port which is not "range compatible".
+             * To fulfill the ISO15118 standard, we simply try to bind to static port numbers.
+             */
+            v2g_ctx->local_tcp_addr->sin6_port = htons(DEFAULT_TCP_PORT);
+            v2g_ctx->tcp_socket = connection_create_socket(v2g_ctx->local_tcp_addr);
+            if (v2g_ctx->tcp_socket < 0) {
+                /* retry until interface is ready */
+                sleep(1);
+                continue;
+            }
+            if (inet_ntop(AF_INET6, &v2g_ctx->local_tcp_addr->sin6_addr, buffer, sizeof(buffer)) != nullptr) {
+                dlog(DLOG_LEVEL_INFO, "TCP server on %s is listening on port [%s%%%" PRIu32 "]:%" PRIu16,
+                     v2g_ctx->if_name, buffer, v2g_ctx->local_tcp_addr->sin6_scope_id,
+                     ntohs(v2g_ctx->local_tcp_addr->sin6_port));
+            } else {
+                dlog(DLOG_LEVEL_ERROR, "TCP server on %s is listening, but inet_ntop failed: %s", v2g_ctx->if_name,
+                     strerror(errno));
+                return -1;
+            }
+        }
+
+        if (v2g_ctx->local_tls_addr) {
+            char buffer[INET6_ADDRSTRLEN];
+
+            /* see comment above for reason */
+            v2g_ctx->local_tls_addr->sin6_port = htons(DEFAULT_TLS_PORT);
+
+            v2g_ctx->tls_socket.fd = connection_create_socket(v2g_ctx->local_tls_addr);
+            if (v2g_ctx->tls_socket.fd < 0) {
+                if (v2g_ctx->tcp_socket != -1) {
+                    /* free the TCP socket */
+                    close(v2g_ctx->tcp_socket);
+                }
+                /* retry until interface is ready */
+                sleep(1);
+                continue;
+            }
+
+            if (inet_ntop(AF_INET6, &v2g_ctx->local_tls_addr->sin6_addr, buffer, sizeof(buffer)) != nullptr) {
+                dlog(DLOG_LEVEL_INFO, "TLS server on %s is listening on port [%s%%%" PRIu32 "]:%" PRIu16,
+                     v2g_ctx->if_name, buffer, v2g_ctx->local_tls_addr->sin6_scope_id,
+                     ntohs(v2g_ctx->local_tls_addr->sin6_port));
+            } else {
+                dlog(DLOG_LEVEL_INFO, "TLS server on %s is listening, but inet_ntop failed: %s", v2g_ctx->if_name,
+                     strerror(errno));
+                return -1;
+            }
+        }
+        /* Sockets should be ready, leave the loop */
+        break;
+    }
+
+    if (v2g_ctx->local_tls_addr) {
+        return tls::connection_init(v2g_ctx);
+    }
+    return 0;
+}
+
+/*!
+ * \brief is_sequence_timeout This function checks if a sequence timeout has occurred.
+ * \param ts_start Is the time after waiting of the next request message.
+ * \param ctx is the V2G context.
+ * \return Returns \c true if a timeout has occurred, otherwise \c false
+ */
+bool is_sequence_timeout(struct timespec ts_start, struct v2g_context* ctx) {
+    struct timespec ts_current;
+    int sequence_timeout = V2G_SEQUENCE_TIMEOUT_60S;
+
+    if (((clock_gettime(CLOCK_MONOTONIC, &ts_current)) != 0) ||
+        (timespec_to_ms(timespec_sub(ts_current, ts_start)) > sequence_timeout)) {
+        dlog(DLOG_LEVEL_ERROR, "Sequence timeout has occurred (message: %s)", v2g_msg_type[ctx->current_v2g_msg]);
+        return true;
+    }
+    return false;
+}
+
+/*!
+ * \brief connection_read This function reads from socket until requested bytes are received or sequence
+ * timeout is reached
+ * \param conn is the v2g connection context
+ * \param buf is the buffer to store the v2g message
+ * \param count is the number of bytes to read
+ * \return Returns \c true if a timeout has occurred, otherwise \c false
+ */
+ssize_t connection_read(struct v2g_connection* conn, unsigned char* buf, size_t count) {
+    struct timespec ts_start;
+    int bytes_read = 0;
+
+    if (clock_gettime(CLOCK_MONOTONIC, &ts_start) == -1) {
+        dlog(DLOG_LEVEL_ERROR, "clock_gettime(ts_start) failed: %s", strerror(errno));
+        return -1;
+    }
+
+    /* loop until we got all requested bytes or sequence timeout DIN [V2G-DC-432]*/
+    while ((bytes_read < count) && (is_sequence_timeout(ts_start, conn->ctx) == false) &&
+           (conn->ctx->is_connection_terminated == false)) { // [V2G2-536]
+
+        int num_of_bytes;
+
+        if (conn->is_tls_connection) {
+            return -1; // shouldn't be using this function
+        }
+        /* use select for timeout handling */
+        struct timeval tv;
+        fd_set read_fds;
+
+        FD_ZERO(&read_fds);
+        FD_SET(conn->conn.socket_fd, &read_fds);
+
+        tv.tv_sec = conn->ctx->network_read_timeout / 1000;
+        tv.tv_usec = (conn->ctx->network_read_timeout % 1000) * 1000;
+
+        num_of_bytes = select(conn->conn.socket_fd + 1, &read_fds, nullptr, nullptr, &tv);
+
+        if (num_of_bytes == -1) {
+            if (errno == EINTR)
+                continue;
+
+            return -1;
+        }
+
+        /* Zero fds ready means we timed out, so let upper loop check our sequence timeout */
+        if (num_of_bytes == 0) {
+            continue;
+        }
+
+        num_of_bytes = (int)read(conn->conn.socket_fd, &buf[bytes_read], count - bytes_read);
+
+        if (num_of_bytes == -1) {
+            if (errno == EINTR)
+                continue;
+
+            return -1;
+        }
+
+        /* return when peer closed connection */
+        if (num_of_bytes == 0)
+            return bytes_read;
+
+        bytes_read += num_of_bytes;
+    }
+
+    if (conn->ctx->is_connection_terminated == true) {
+        dlog(DLOG_LEVEL_ERROR, "Reading from tcp-socket aborted");
+        return -2;
+    }
+
+    return (ssize_t)bytes_read; // [V2G2-537] read bytes are currupted if reading from socket was interrupted
+                                // (V2G_SECC_Sequence_Timeout)
+}
+
+/*!
+ * \brief connection_read This function writes to socket until bytes are written to the socket
+ * \param conn is the v2g connection context
+ * \param buf is the buffer where the v2g message is stored
+ * \param count is the number of bytes to write
+ * \return Returns \c true if a timeout has occurred, otherwise \c false
+ */
+ssize_t connection_write(struct v2g_connection* conn, unsigned char* buf, size_t count) {
+    int bytes_written = 0;
+
+    /* loop until we got all requested bytes out */
+    while (bytes_written < count) {
+        int num_of_bytes = (int)write(conn->conn.socket_fd, &buf[bytes_written], count - bytes_written);
+        if (conn->is_tls_connection) {
+            return -1; // shouldn't be using this function
+        }
+        if (num_of_bytes == -1) {
+            if (errno == EINTR)
+                continue;
+
+            return -1;
+        }
+
+        /* return when peer closed connection */
+        if (num_of_bytes == 0)
+            return bytes_written;
+
+        bytes_written += num_of_bytes;
+    }
+
+    return (ssize_t)bytes_written;
+}
+
+static std::optional<types::evse_manager::HlcSessionFailedReasonEnum>
+map_v2g_msg_to_hlc_failed_reason(V2gMsgTypeId msg, bool tls_handshake_failed) {
+    using Reason = types::evse_manager::HlcSessionFailedReasonEnum;
+    if (tls_handshake_failed) {
+        return Reason::FailedTLSHandshake;
+    }
+    switch (msg) {
+    case V2G_SUPPORTED_APP_PROTOCOL_MSG:
+    case V2G_SESSION_SETUP_MSG:
+        return Reason::ProtocolNegotiationFailed;
+    case V2G_SERVICE_DISCOVERY_MSG:
+    case V2G_SERVICE_DETAIL_MSG:
+    case V2G_CHARGE_PARAMETER_DISCOVERY_MSG:
+        return Reason::ChargingParametersNotAccepted;
+    case V2G_PAYMENT_SERVICE_SELECTION_MSG:
+    case V2G_PAYMENT_DETAILS_MSG:
+    case V2G_AUTHORIZATION_MSG:
+    case V2G_CERTIFICATE_UPDATE_MSG:
+    case V2G_CERTIFICATE_INSTALLATION_MSG:
+        return Reason::AuthorizationFailed;
+    case V2G_CABLE_CHECK_MSG:
+    case V2G_PRE_CHARGE_MSG:
+    case V2G_POWER_DELIVERY_MSG:
+        return Reason::EnergyTransferSetupFailed;
+    case V2G_CURRENT_DEMAND_MSG:
+    case V2G_CHARGING_STATUS_MSG:
+    case V2G_METERING_RECEIPT_MSG:
+        return Reason::ChargingInterrupted;
+    case V2G_SESSION_STOP_MSG:
+    case V2G_WELDING_DETECTION_MSG:
+        return std::nullopt;
+    default:
+        return Reason::UnexpectedSessionEnd;
+    }
+}
+
+/*!
+ * \brief connection_teardown This function must be called on connection teardown.
+ * \param conn is the V2G connection context
+ */
+void connection_teardown(struct v2g_connection* conn) {
+    if (conn->ctx->session.is_charging == true) {
+        conn->ctx->p_charger->publish_current_demand_finished(nullptr);
+
+        if (conn->ctx->is_dc_charger == true) {
+            conn->ctx->p_charger->publish_dc_open_contactor(nullptr);
+        } else {
+            conn->ctx->p_charger->publish_ac_open_contactor(nullptr);
+        }
+    }
+
+    const V2gMsgTypeId last_msg = conn->last_v2g_msg_at_disconnect;
+    const bool evse_initiated_stop = conn->ctx->stop_hlc || conn->ctx->intl_emergency_shutdown;
+
+    /* init charging session */
+    v2g_ctx_init_charging_session(conn->ctx, true);
+
+    if (!evse_initiated_stop && (conn->d_link_action == dLinkAction::D_LINK_ACTION_TERMINATE ||
+                                 conn->d_link_action == dLinkAction::D_LINK_ACTION_ERROR)) {
+        if (const auto reason = map_v2g_msg_to_hlc_failed_reason(last_msg, conn->tls_handshake_failed)) {
+            conn->ctx->p_charger->publish_hlc_session_failed(*reason);
+        }
+    }
+
+    /* print dlink status */
+    switch (conn->d_link_action) {
+    case dLinkAction::D_LINK_ACTION_ERROR:
+        conn->ctx->p_charger->publish_dlink_error(nullptr);
+        dlog(DLOG_LEVEL_TRACE, "d_link/error");
+        break;
+    case dLinkAction::D_LINK_ACTION_TERMINATE:
+        conn->ctx->p_charger->publish_dlink_terminate(nullptr);
+        dlog(DLOG_LEVEL_TRACE, "d_link/terminate");
+        break;
+    case dLinkAction::D_LINK_ACTION_PAUSE:
+        conn->ctx->p_charger->publish_dlink_pause(nullptr);
+        dlog(DLOG_LEVEL_TRACE, "d_link/pause");
+        break;
+    }
+}
+
+static void wait_for_peer_close(int fd, int timeout_ms) {
+    struct pollfd pfd = {};
+    pfd.fd = fd;
+    pfd.events = POLLIN | POLLHUP;
+
+    int rc = poll(&pfd, 1, timeout_ms);
+    if (rc <= 0) {
+        return;
+    }
+
+    if (pfd.revents & (POLLIN | POLLHUP)) {
+        char buf[64];
+        while (recv(fd, buf, sizeof(buf), MSG_DONTWAIT) > 0) {
+        }
+    }
+}
+
+/**
+ * This is the 'main' function of a thread, which handles a TCP connection.
+ */
+static void* connection_handle_tcp(void* data) {
+    struct v2g_connection* conn = static_cast<struct v2g_connection*>(data);
+    int rv = 0;
+    bool error_occurred{false};
+
+    dlog(DLOG_LEVEL_INFO, "Started new TCP connection thread");
+
+    remove_service_from_service_list_if_exists(conn->ctx, V2G_SERVICE_ID_CERTIFICATE);
+
+    /* check if the v2g-session is already running in another thread, if not, handle v2g-connection */
+    if (conn->ctx->state == 0) {
+        int rv2 = v2g_handle_connection(conn);
+
+        if (rv2 != 0) {
+            dlog(DLOG_LEVEL_INFO, "v2g_handle_connection exited with %d", rv2);
+        }
+    } else {
+        rv = ERROR_SESSION_ALREADY_STARTED;
+        dlog(DLOG_LEVEL_WARNING, "%s", "Closing tcp-connection. v2g-session is already running");
+    }
+
+    /* tear down connection gracefully */
+    dlog(DLOG_LEVEL_INFO, "Closing TCP connection");
+
+    /* some EV's did not like the immediate shutdown. Therefore we sleep for 2 seconds */
+    std::this_thread::sleep_for(std::chrono::seconds(2));
+
+    if (shutdown(conn->conn.socket_fd, SHUT_WR) == -1) {
+        dlog(DLOG_LEVEL_ERROR, "shutdown() failed: %s", strerror(errno));
+        error_occurred = true;
+    }
+
+    /* wait briefly for peer FIN or timeout */
+    wait_for_peer_close(conn->conn.socket_fd, CLIENT_FIN_TIMEOUT);
+
+    if (close(conn->conn.socket_fd) == -1) {
+        dlog(DLOG_LEVEL_ERROR, "close() failed: %s", strerror(errno));
+        error_occurred = true;
+    }
+
+    if (not error_occurred) {
+        dlog(DLOG_LEVEL_INFO, "TCP connection closed gracefully");
+    }
+
+    conn->ctx->connection_initiated = false;
+
+    if (rv != ERROR_SESSION_ALREADY_STARTED) {
+        /* cleanup and notify lower layers */
+        connection_teardown(conn);
+    }
+
+    free(conn);
+
+    return nullptr;
+}
+
+static void* connection_server(void* data) {
+    struct v2g_context* ctx = static_cast<v2g_context*>(data);
+    ctx->connection_initiated = false;
+    struct v2g_connection* conn = NULL;
+    pthread_attr_t attr;
+
+    /* create the thread in detached state so we don't need to join every single one */
+    if (pthread_attr_init(&attr) != 0) {
+        dlog(DLOG_LEVEL_ERROR, "pthread_attr_init failed: %s", strerror(errno));
+        goto thread_exit;
+    }
+    if (pthread_attr_setdetachstate(&attr, PTHREAD_CREATE_DETACHED) != 0) {
+        dlog(DLOG_LEVEL_ERROR, "pthread_attr_setdetachstate failed: %s", strerror(errno));
+        goto thread_exit;
+    }
+
+    while (1) {
+        char client_addr[INET6_ADDRSTRLEN];
+        struct sockaddr_in6 addr;
+        socklen_t addrlen = sizeof(addr);
+
+        /* cleanup old one and create new connection context */
+        free(conn);
+        conn = static_cast<v2g_connection*>(calloc(1, sizeof(*conn)));
+        if (!conn) {
+            dlog(DLOG_LEVEL_ERROR, "Calloc failed: %s", strerror(errno));
+            break;
+        }
+
+        /* setup common stuff */
+        conn->ctx = ctx;
+        conn->read = &connection_read;
+        conn->write = &connection_write;
+        conn->is_tls_connection = false;
+
+        /* wait for an incoming connection */
+        conn->conn.socket_fd = accept(ctx->tcp_socket, (struct sockaddr*)&addr, &addrlen);
+        if (conn->conn.socket_fd == -1) {
+            dlog(DLOG_LEVEL_ERROR, "Accept(tcp) failed: %s", strerror(errno));
+            continue;
+        }
+
+        if (inet_ntop(AF_INET6, &addr, client_addr, sizeof(client_addr)) != NULL) {
+            dlog(DLOG_LEVEL_INFO, "Incoming connection on %s from [%s]:%" PRIu16, ctx->if_name, client_addr,
+                 ntohs(addr.sin6_port));
+        } else {
+            dlog(DLOG_LEVEL_ERROR, "Incoming connection on %s, but inet_ntop failed: %s", ctx->if_name,
+                 strerror(errno));
+        }
+
+        // store the port to create a udp socket
+        conn->ctx->udp_port = ntohs(addr.sin6_port);
+
+        if (ctx->connection_initiated) {
+            dlog(DLOG_LEVEL_ERROR, "Incoming connection on %s, but there is already an active connection.",
+                 ctx->if_name);
+            connection_teardown(conn);
+            free(conn);
+            conn = NULL;
+            continue;
+        }
+        ctx->connection_initiated = true;
+
+        if (pthread_create(&conn->thread_id, &attr, connection_handle_tcp, conn) != 0) {
+            dlog(DLOG_LEVEL_ERROR, "pthread_create() failed: %s", strerror(errno));
+            ctx->connection_initiated = false;
+            continue;
+        }
+
+        /* is up to the thread to cleanup conn */
+        conn = NULL;
+    }
+
+thread_exit:
+    if (pthread_attr_destroy(&attr) != 0) {
+        dlog(DLOG_LEVEL_ERROR, "pthread_attr_destroy failed: %s", strerror(errno));
+    }
+
+    /* clean up if dangling */
+    free(conn);
+
+    return NULL;
+}
+
+int connection_start_servers(struct v2g_context* ctx) {
+    int rv, tcp_started = 0;
+
+    if (ctx->tcp_socket != -1) {
+        rv = pthread_create(&ctx->tcp_thread, NULL, connection_server, ctx);
+        if (rv != 0) {
+            dlog(DLOG_LEVEL_ERROR, "pthread_create(tcp) failed: %s", strerror(errno));
+            return -1;
+        }
+        tcp_started = 1;
+    }
+
+    if (ctx->tls_socket.fd != -1) {
+        rv = tls::connection_start_server(ctx);
+        if (rv != 0) {
+            if (tcp_started) {
+                pthread_cancel(ctx->tcp_thread);
+                pthread_join(ctx->tcp_thread, NULL);
+            }
+            dlog(DLOG_LEVEL_ERROR, "pthread_create(tls) failed: %s", strerror(errno));
+            return -1;
+        }
+    }
+
+    return 0;
+}
+
+int create_udp_socket(const uint16_t udp_port, const char* interface_name) {
+    constexpr auto LINK_LOCAL_MULTICAST = "ff02::1";
+
+    int udp_socket = socket(AF_INET6, SOCK_DGRAM, 0);
+    if (udp_socket < 0) {
+        EVLOG_error << "Could not create socket: " << strerror(errno);
+        return udp_socket;
+    }
+
+    // source setup
+
+    // find port between 49152-65535
+    auto could_bind = false;
+    auto source_port = 49152;
+    for (; source_port < 65535; source_port++) {
+        sockaddr_in6 source_address = {AF_INET6, htons(source_port)};
+        if (bind(udp_socket, reinterpret_cast<sockaddr*>(&source_address), sizeof(sockaddr_in6)) == 0) {
+            could_bind = true;
+            break;
+        }
+    }
+
+    if (!could_bind) {
+        EVLOG_error << "Could not bind: " << strerror(errno);
+        return -1;
+    }
+
+    EVLOG_info << "UDP socket bound to source port: " << source_port;
+
+    const auto index = if_nametoindex(interface_name);
+    auto mreq = ipv6_mreq{};
+    mreq.ipv6mr_interface = index;
+    if (inet_pton(AF_INET6, LINK_LOCAL_MULTICAST, &mreq.ipv6mr_multiaddr) <= 0) {
+        EVLOG_error << "Failed to setup multicast address" << strerror(errno);
+        return -1;
+    }
+    if (setsockopt(udp_socket, IPPROTO_IPV6, IPV6_ADD_MEMBERSHIP, &mreq, sizeof(mreq)) < 0) {
+        EVLOG_error << "Could not add multicast group membership: " << strerror(errno);
+        return -1;
+    }
+
+    if (setsockopt(udp_socket, IPPROTO_IPV6, IPV6_MULTICAST_IF, &index, sizeof(index)) < 0) {
+        EVLOG_error << "Could not set interface name: " << interface_name << "with error: " << strerror(errno);
+    }
+
+    // destination setup
+    sockaddr_in6 destination_address = {AF_INET6, htons(udp_port)};
+    if (inet_pton(AF_INET6, LINK_LOCAL_MULTICAST, &destination_address.sin6_addr) <= 0) {
+        EVLOG_error << "Failed to setup server address" << strerror(errno);
+    }
+    const auto connected =
+        connect(udp_socket, reinterpret_cast<sockaddr*>(&destination_address), sizeof(sockaddr_in6)) == 0;
+    if (!connected) {
+        EVLOG_error << "Could not connect: " << strerror(errno);
+        return -1;
+    }
+
+    return udp_socket;
+}