configd: T2582: add shim as config daemon client

2 files changed, 307 insertions, 0 deletions

diff --git a/src/shim/Makefile b/src/shim/Makefile
new file mode 100644
index 000000000..c8487e3c2
--- /dev/null
+++ b/src/shim/Makefile
@@ -0,0 +1,20 @@
+DEBUG = 0
+
+CC := gcc
+CFLAGS := -I./mkjson -L./mkjson/lib -DDEBUG=${DEBUG}
+LIBS := -lmkjson -lzmq
+
+.PHONY: vyshim
+vyshim: vyshim.c libmkjson
+	$(CC) $(CFLAGS) -o $@ $< $(LIBS)
+
+.PHONY: libmkjson
+libmkjson:
+	$(MAKE) -C mkjson
+
+all: vyshim
+
+.PHONY: clean
+clean:
+	$(MAKE) -C mkjson clean
+	rm -f vyshim
diff --git a/src/shim/vyshim.c b/src/shim/vyshim.c
new file mode 100644
index 000000000..8b6feab99
--- /dev/null
+++ b/src/shim/vyshim.c
@@ -0,0 +1,287 @@
+/*
+ * Copyright (C) 2020 VyOS maintainers and contributors
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 or later 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, see <http://www.gnu.org/licenses/>.
+ *
+ */
+
+#include <stdlib.h>
+#include <stdio.h>
+#include <string.h>
+#include <unistd.h>
+#include <string.h>
+#include <sys/time.h>
+#include <time.h>
+#include <stdint.h>
+#include <sys/types.h>
+#include <sys/wait.h>
+#include <zmq.h>
+#include "mkjson.h"
+
+/*
+ *
+ *
+ */
+
+#if DEBUG
+#define DEBUG_ON 1
+#else
+#define DEBUG_ON 0
+#endif
+#define debug_print(fmt, ...) \
+    do { if (DEBUG_ON) fprintf(stderr, fmt, ##__VA_ARGS__); } while (0)
+#define debug_call(f) \
+    do { if (DEBUG_ON) f; } while (0)
+
+#define SOCKET_PATH "ipc:///run/vyos-configd.sock"
+
+#define GET_ACTIVE "cli-shell-api --show-active-only --show-show-defaults --show-ignore-edit showConfig"
+#define GET_SESSION "cli-shell-api --show-working-only --show-show-defaults --show-ignore-edit showConfig"
+
+#define COMMIT_MARKER "/var/tmp/initial_in_commit"
+
+enum {
+    SUCCESS =      1 << 0,
+    ERROR_COMMIT = 1 << 1,
+    ERROR_DAEMON = 1 << 2,
+    PASS =         1 << 3
+};
+
+volatile int init_alarm = 0;
+volatile int timeout = 0;
+
+int initialization(void *);
+int pass_through(char **, int);
+void timer_handler(int);
+
+double get_posix_clock_time(void);
+
+int main(int argc, char* argv[])
+{
+    // string for node data: conf_mode script and tagnode, if applicable
+    char string_node_data[256];
+    string_node_data[0] = '\0';
+
+    void *context = zmq_ctx_new();
+    void *requester = zmq_socket(context, ZMQ_REQ);
+
+    int init_timeout = 0;
+
+    debug_print("Connecting to vyos-configd ...\n");
+    zmq_connect(requester, SOCKET_PATH);
+
+    if (access(COMMIT_MARKER, F_OK) != -1) {
+        init_timeout = initialization(requester);
+        if (!init_timeout) remove(COMMIT_MARKER);
+    }
+
+    int end = argc > 3 ? 2 : argc - 1;
+
+    // if initial communication failed, pass through execution of script
+    if (init_timeout) {
+        int ret = pass_through(argv, end);
+        return ret;
+    }
+
+    for (int i = end; i > 0 ; i--) {
+        strncat(&string_node_data[0], argv[i], 127);
+    }
+
+    char error_code[1];
+    debug_print("Sending node data ...\n");
+    char *string_node_data_msg = mkjson(MKJSON_OBJ, 2,
+                                        MKJSON_STRING, "type", "node",
+                                        MKJSON_STRING, "data", &string_node_data[0]);
+
+    zmq_send(requester, string_node_data_msg, strlen(string_node_data_msg), 0);
+    zmq_recv(requester, error_code, 1, 0);
+    debug_print("Received node data receipt\n");
+
+    int err = (int)error_code[0];
+
+    free(string_node_data_msg);
+
+    zmq_close(requester);
+    zmq_ctx_destroy(context);
+
+    if (err & PASS) {
+        debug_print("Received PASS\n");
+        int ret = pass_through(argv, end);
+        return ret;
+    }
+
+    if (err & ERROR_DAEMON) {
+        debug_print("Received ERROR_DAEMON\n");
+        int ret = pass_through(argv, end);
+        return ret;
+    }
+
+    if (err & ERROR_COMMIT) {
+        debug_print("Received ERROR_COMMIT\n");
+        return -1;
+    }
+
+    return 0;
+}
+
+int initialization(void* Requester)
+{
+    char *active_str = NULL;
+    size_t active_len = 0;
+
+    char *session_str = NULL;
+    size_t session_len = 0;
+
+    char *empty_string = "\n";
+
+    char buffer[16];
+
+    struct sigaction sa;
+    struct itimerval timer, none_timer;
+
+    memset(&sa, 0, sizeof(sa));
+    sa.sa_handler = &timer_handler;
+    sigaction(SIGALRM, &sa, NULL);
+
+    timer.it_value.tv_sec = 0;
+    timer.it_value.tv_usec = 10000;
+    timer.it_interval.tv_sec = timer.it_interval.tv_usec = 0;
+    none_timer.it_value.tv_sec = none_timer.it_value.tv_usec = 0;
+    none_timer.it_interval.tv_sec = none_timer.it_interval.tv_usec = 0;
+
+    double prev_time_value, time_value;
+    double time_diff;
+
+    debug_print("Sending init announcement\n");
+    char *init_announce = mkjson(MKJSON_OBJ, 1,
+                                 MKJSON_STRING, "type", "init");
+
+    // check for timeout on initial contact
+    while (!init_alarm) {
+        debug_call(prev_time_value = get_posix_clock_time());
+
+        setitimer(ITIMER_REAL, &timer, NULL);
+
+        zmq_send(Requester, init_announce, strlen(init_announce), 0);
+        zmq_recv(Requester, buffer, 16, 0);
+
+        setitimer(ITIMER_REAL, &none_timer, &timer);
+
+        debug_call(time_value = get_posix_clock_time());
+
+        debug_print("Received init receipt\n");
+        debug_call(time_diff = time_value - prev_time_value);
+        debug_print("time elapse %f\n", time_diff);
+
+        break;
+    }
+
+    free(init_announce);
+
+    if (timeout) return -1;
+
+    FILE *fp_a = popen(GET_ACTIVE, "r");
+    getdelim(&active_str, &active_len, '\0', fp_a);
+    int ret = pclose(fp_a);
+
+    if (!ret) {
+        debug_print("Sending active config\n");
+        zmq_send(Requester, active_str, active_len - 1, 0);
+        zmq_recv(Requester, buffer, 16, 0);
+        debug_print("Received active receipt\n");
+    } else {
+        debug_print("Sending empty active config\n");
+        zmq_send(Requester, empty_string, 0, 0);
+        zmq_recv(Requester, buffer, 16, 0);
+        debug_print("Received active receipt\n");
+    }
+
+    free(active_str);
+
+    FILE *fp_s = popen(GET_SESSION, "r");
+    getdelim(&session_str, &session_len, '\0', fp_s);
+    pclose(fp_s);
+
+    debug_print("Sending session config\n");
+    zmq_send(Requester, session_str, session_len - 1, 0);
+    zmq_recv(Requester, buffer, 16, 0);
+    debug_print("Received session receipt\n");
+
+    free(session_str);
+
+    return 0;
+}
+
+int pass_through(char **argv, int end)
+{
+    char *newargv[] = { NULL, NULL };
+    pid_t child_pid;
+
+    newargv[0] = argv[end];
+    if (end > 1) {
+        putenv(argv[end - 1]);
+    }
+
+    debug_print("pass-through invoked\n");
+
+    if ((child_pid=fork()) < 0) {
+        debug_print("fork() failed\n");
+        return -1;
+    } else if (child_pid == 0) {
+        if (-1 == execv(argv[end], newargv)) {
+            debug_print("pass_through execve failed %s: %s\n",
+                        argv[end], strerror(errno));
+            return -1;
+        }
+    } else if (child_pid > 0) {
+        int status;
+        pid_t wait_pid = waitpid(child_pid, &status, 0);
+         if (wait_pid < 0) {
+             debug_print("waitpid() failed\n");
+             return -1;
+         } else if (wait_pid == child_pid) {
+             if (WIFEXITED(status)) {
+                 debug_print("child exited with code %d\n",
+                             WEXITSTATUS(status));
+                 return WEXITSTATUS(status);
+             }
+         }
+    }
+
+    return 0;
+}
+
+void timer_handler(int signum)
+{
+    debug_print("timer_handler invoked\n");
+    timeout = 1;
+    init_alarm = 1;
+
+    return;
+}
+
+#ifdef _POSIX_MONOTONIC_CLOCK
+double get_posix_clock_time(void)
+{
+    struct timespec ts;
+
+    if (clock_gettime(CLOCK_MONOTONIC, &ts) == 0) {
+        return (double) (ts.tv_sec + ts.tv_nsec / 1000000000.0);
+    } else {
+        return 0;
+    }
+}
+#else
+double get_posix_clock_time(void)
+{return (double)0;}
+#endif