build: Move connmgr and enrolment to common ground

The connection manager and enrolment components of the unicast and
broadcast IPCP have a lot in common, as conjectured in the paper. The
initial implementation of the broadcast IPCP just duplicated the
code. This moves the shared functionality to common ground.

Signed-off-by: Dimitri Staessens <dimitri@ouroboros.rocks>
Signed-off-by: Sander Vrijders <sander@ouroboros.rocks>

1 files changed, 385 insertions, 0 deletions

diff --git a/src/ipcpd/common/enroll.c b/src/ipcpd/common/enroll.c
new file mode 100644
index 00000000..090067d8
--- /dev/null
+++ b/src/ipcpd/common/enroll.c
@@ -0,0 +1,385 @@
+/*
+ * Ouroboros - Copyright (C) 2016 - 2021
+ *
+ * Enrollment Task
+ *
+ *    Dimitri Staessens <dimitri@ouroboros.rocks>
+ *    Sander Vrijders   <sander@ouroboros.rocks>
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 as
+ * published by the Free Software Foundation.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, Inc., http://www.fsf.org/about/contact/.
+ */
+
+#if defined(__linux__) || defined(__CYGWIN__)
+#define _DEFAULT_SOURCE
+#else
+#define _POSIX_C_SOURCE 199309L
+#endif
+
+#define OUROBOROS_PREFIX "enrollment"
+
+#include <ouroboros/endian.h>
+#include <ouroboros/errno.h>
+#include <ouroboros/time_utils.h>
+#include <ouroboros/dev.h>
+#include <ouroboros/logs.h>
+#include <ouroboros/errno.h>
+#include <ouroboros/sockets.h>
+
+#include "common/connmgr.h"
+#include "common/enroll.h"
+#include "ipcp.h"
+
+#include <assert.h>
+#include <stdlib.h>
+#include <string.h>
+#include <pthread.h>
+
+#include "ipcp_config.pb-c.h"
+typedef EnrollMsg enroll_msg_t;
+
+#define ENROLL_COMP             "Enrollment"
+#define ENROLL_PROTO            "OEP" /* Ouroboros enrollment protocol */
+#define ENROLL_WARN_TIME_OFFSET 20
+#define ENROLL_BUF_LEN          1024
+
+enum enroll_state {
+        ENROLL_NULL = 0,
+        ENROLL_INIT,
+        ENROLL_RUNNING
+};
+
+struct {
+        struct ipcp_config conf;
+        enum enroll_state  state;
+        pthread_t          listener;
+} enroll;
+
+static int send_rcv_enroll_msg(int fd)
+{
+        enroll_msg_t    req = ENROLL_MSG__INIT;
+        enroll_msg_t *  reply;
+        uint8_t         buf[ENROLL_BUF_LEN];
+        ssize_t         len;
+        ssize_t         delta_t;
+        struct timespec t0;
+        struct timespec rtt;
+
+        req.code = ENROLL_CODE__ENROLL_REQ;
+
+        len = enroll_msg__get_packed_size(&req);
+        if (len < 0) {
+                log_dbg("Failed pack request message.");
+                return -1;
+        }
+
+        enroll_msg__pack(&req, buf);
+
+        clock_gettime(CLOCK_REALTIME, &t0);
+
+        if (flow_write(fd, buf, len) < 0) {
+                log_dbg("Failed to send request message.");
+                return -1;
+        }
+
+        len = flow_read(fd, buf, ENROLL_BUF_LEN);
+        if (len < 0) {
+                log_dbg("No enrollment reply received.");
+                return -1;
+        }
+
+        log_dbg("Received enrollment info (%zd bytes).", len);
+
+        reply = enroll_msg__unpack(NULL, len, buf);
+        if (reply == NULL) {
+                log_dbg("No enrollment response.");
+                return -1;
+        }
+
+        if (reply->code != ENROLL_CODE__ENROLL_BOOT) {
+                log_dbg("Failed to unpack enrollment response.");
+                enroll_msg__free_unpacked(reply, NULL);
+                return -1;
+        }
+
+        if (!(reply->has_t_sec && reply->has_t_nsec)) {
+                log_dbg("No time in response message.");
+                enroll_msg__free_unpacked(reply, NULL);
+                return -1;
+        }
+
+        clock_gettime(CLOCK_REALTIME, &rtt);
+
+        delta_t = ts_diff_ms(&t0, &rtt);
+
+        rtt.tv_sec  = reply->t_sec;
+        rtt.tv_nsec = reply->t_nsec;
+
+        if (labs(ts_diff_ms(&t0, &rtt)) - delta_t > ENROLL_WARN_TIME_OFFSET)
+                log_warn("Clock offset above threshold.");
+
+        strcpy(enroll.conf.layer_info.layer_name,
+               reply->conf->layer_info->layer_name);
+        enroll.conf.type           = reply->conf->ipcp_type;
+#ifdef BUILD_IPCP_UNICAST
+        enroll.conf.addr_size      = reply->conf->addr_size;
+        enroll.conf.eid_size       = reply->conf->eid_size;
+        enroll.conf.max_ttl        = reply->conf->max_ttl;
+        enroll.conf.addr_auth_type = reply->conf->addr_auth_type;
+        enroll.conf.routing_type   = reply->conf->routing_type;
+        enroll.conf.cong_avoid     = reply->conf->cong_avoid;
+#endif
+        enroll.conf.layer_info.dir_hash_algo
+                = reply->conf->layer_info->dir_hash_algo;
+        enroll_msg__free_unpacked(reply, NULL);
+
+        return 0;
+}
+
+static ssize_t enroll_pack(uint8_t ** buf)
+{
+        enroll_msg_t      msg        = ENROLL_MSG__INIT;
+        ipcp_config_msg_t config     = IPCP_CONFIG_MSG__INIT;
+        layer_info_msg_t  layer_info = LAYER_INFO_MSG__INIT;
+        struct timespec   now;
+        ssize_t           len;
+
+        clock_gettime(CLOCK_REALTIME, &now);
+
+        msg.code       = ENROLL_CODE__ENROLL_BOOT;
+        msg.has_t_sec  = true;
+        msg.t_sec      = now.tv_sec;
+        msg.has_t_nsec = true;
+        msg.t_nsec     = now.tv_nsec;
+        msg.conf       = &config;
+
+        config.ipcp_type          = enroll.conf.type;
+#ifdef BUILD_IPCP_UNICAST
+        config.has_addr_size      = true;
+        config.addr_size          = enroll.conf.addr_size;
+        config.has_eid_size       = true;
+        config.eid_size           = enroll.conf.eid_size;
+        config.has_max_ttl        = true;
+        config.max_ttl            = enroll.conf.max_ttl;
+        config.has_addr_auth_type = true;
+        config.addr_auth_type     = enroll.conf.addr_auth_type;
+        config.has_routing_type   = true;
+        config.routing_type       = enroll.conf.routing_type;
+        config.has_cong_avoid     = true;
+        config.cong_avoid         = enroll.conf.cong_avoid;
+#endif
+        config.layer_info         = &layer_info;
+
+        layer_info.layer_name     = (char *) enroll.conf.layer_info.layer_name;
+        layer_info.dir_hash_algo  = enroll.conf.layer_info.dir_hash_algo;
+
+        len = enroll_msg__get_packed_size(&msg);
+
+        *buf = malloc(len);
+        if (*buf == NULL)
+                return -1;
+
+        enroll_msg__pack(&msg, *buf);
+
+        return len;
+}
+
+static void * enroll_handle(void * o)
+{
+        struct conn    conn;
+        uint8_t        buf[ENROLL_BUF_LEN];
+        uint8_t *      reply;
+        ssize_t        len;
+        enroll_msg_t * msg;
+
+        (void) o;
+
+        while (true) {
+                if (connmgr_wait(COMPID_ENROLL, &conn)) {
+                        log_err("Failed to get next connection.");
+                        continue;
+                }
+
+                len = flow_read(conn.flow_info.fd, buf, ENROLL_BUF_LEN);
+                if (len < 0) {
+                        log_err("Failed to read from flow.");
+                        connmgr_dealloc(COMPID_ENROLL, &conn);
+                        continue;
+                }
+
+                msg = enroll_msg__unpack(NULL, len, buf);
+                if (msg == NULL) {
+                        log_err("Failed to unpack message.");
+                        connmgr_dealloc(COMPID_ENROLL, &conn);
+                        continue;
+                }
+
+                if (msg->code != ENROLL_CODE__ENROLL_REQ) {
+                        log_err("Wrong message type.");
+                        connmgr_dealloc(COMPID_ENROLL, &conn);
+                        enroll_msg__free_unpacked(msg, NULL);
+                        continue;
+                }
+
+                log_dbg("Enrolling a new neighbor.");
+
+                enroll_msg__free_unpacked(msg, NULL);
+
+                len = enroll_pack(&reply);
+                if (reply == NULL) {
+                        log_err("Failed to pack enrollment message.");
+                        connmgr_dealloc(COMPID_ENROLL, &conn);
+                        continue;
+                }
+
+                log_dbg("Sending enrollment info (%zd bytes).", len);
+
+                if (flow_write(conn.flow_info.fd, reply, len) < 0) {
+                        log_err("Failed respond to enrollment request.");
+                        connmgr_dealloc(COMPID_ENROLL, &conn);
+                        free(reply);
+                        continue;
+                }
+
+                free(reply);
+
+                len = flow_read(conn.flow_info.fd, buf, ENROLL_BUF_LEN);
+                if (len < 0) {
+                        log_err("Failed to read from flow.");
+                        connmgr_dealloc(COMPID_ENROLL, &conn);
+                        continue;
+                }
+
+                msg = enroll_msg__unpack(NULL, len, buf);
+                if (msg == NULL) {
+                        log_err("Failed to unpack message.");
+                        connmgr_dealloc(COMPID_ENROLL, &conn);
+                        continue;
+                }
+
+                if (msg->code != ENROLL_CODE__ENROLL_DONE || !msg->has_result) {
+                        log_err("Wrong message type.");
+                        enroll_msg__free_unpacked(msg, NULL);
+                        connmgr_dealloc(COMPID_ENROLL, &conn);
+                        continue;
+                }
+
+                if (msg->result == 0)
+                        log_dbg("Neighbor enrollment successful.");
+                else
+                        log_dbg("Neigbor reported failed enrollment.");
+
+                enroll_msg__free_unpacked(msg, NULL);
+
+                connmgr_dealloc(COMPID_ENROLL, &conn);
+        }
+
+        return 0;
+}
+
+int enroll_boot(struct conn * conn)
+{
+        log_dbg("Getting boot information.");
+
+        if (send_rcv_enroll_msg(conn->flow_info.fd)) {
+                log_err("Failed to enroll.");
+                return -1;
+        }
+
+        return 0;
+}
+
+int enroll_done(struct conn * conn,
+                int           result)
+{
+        enroll_msg_t msg = ENROLL_MSG__INIT;
+        uint8_t      buf[ENROLL_BUF_LEN];
+        ssize_t       len;
+
+        msg.code       = ENROLL_CODE__ENROLL_DONE;
+        msg.has_result = true;
+        msg.result     = result;
+
+        len = enroll_msg__get_packed_size(&msg);
+        if (len < 0) {
+                log_dbg("Failed pack request message.");
+                return -1;
+        }
+
+        enroll_msg__pack(&msg, buf);
+
+        if (flow_write(conn->flow_info.fd, buf, len) < 0) {
+                log_dbg("Failed to send acknowledgment.");
+                return -1;
+        }
+
+        return 0;
+}
+
+void enroll_bootstrap(const struct ipcp_config * conf)
+{
+        assert(conf);
+
+        memcpy(&enroll.conf, conf, sizeof(enroll.conf));
+}
+
+struct ipcp_config * enroll_get_conf(void)
+{
+        return &enroll.conf;
+}
+
+int enroll_init(void)
+{
+        struct conn_info info;
+
+        memset(&info, 0, sizeof(info));
+
+        strcpy(info.comp_name, ENROLL_COMP);
+        strcpy(info.protocol, ENROLL_PROTO);
+        info.pref_version = 1;
+        info.pref_syntax  = PROTO_GPB;
+        info.addr         = 0;
+
+        if (connmgr_comp_init(COMPID_ENROLL, &info)) {
+                log_err("Failed to register with connmgr.");
+                return -1;
+        }
+
+        enroll.state = ENROLL_INIT;
+
+        return 0;
+}
+
+void enroll_fini(void)
+{
+        if (enroll.state == ENROLL_RUNNING)
+                pthread_join(enroll.listener, NULL);
+
+        connmgr_comp_fini(COMPID_ENROLL);
+}
+
+int enroll_start(void)
+{
+        if (pthread_create(&enroll.listener, NULL, enroll_handle, NULL))
+                return -1;
+
+        enroll.state = ENROLL_RUNNING;
+
+        return 0;
+}
+
+void enroll_stop(void)
+{
+        if (enroll.state == ENROLL_RUNNING)
+                pthread_cancel(enroll.listener);
+}