ncd: modules: add net_ipv6_wait_dynamic_addr

blog_channels.txt

@@ -107,3 +107,4 @@ ncd_value 4
 ncd_try 4
 ncd_sys_request_server 4
 NCDRequest 4
+ncd_net_ipv6_wait_dynamic_addr 4

generated/blog_channel_ncd_net_ipv6_wait_dynamic_addr.h

@@ -0,0 +1,4 @@
+#ifdef BLOG_CURRENT_CHANNEL
+#undef BLOG_CURRENT_CHANNEL
+#endif
+#define BLOG_CURRENT_CHANNEL BLOG_CHANNEL_ncd_net_ipv6_wait_dynamic_addr

generated/blog_channels_defines.h

@@ -107,4 +107,5 @@
 #define BLOG_CHANNEL_ncd_try 106
 #define BLOG_CHANNEL_ncd_sys_request_server 107
 #define BLOG_CHANNEL_NCDRequest 108
-#define BLOG_NUM_CHANNELS 109
+#define BLOG_CHANNEL_ncd_net_ipv6_wait_dynamic_addr 109
+#define BLOG_NUM_CHANNELS 110

generated/blog_channels_list.h

@@ -107,3 +107,4 @@
 {.name = "ncd_try", .loglevel = 4},
 {.name = "ncd_sys_request_server", .loglevel = 4},
 {.name = "NCDRequest", .loglevel = 4},
+{.name = "ncd_net_ipv6_wait_dynamic_addr", .loglevel = 4},

ncd/CMakeLists.txt

@@ -101,6 +101,7 @@ add_executable(badvpn-ncd
     modules/sys_watch_input.c
     modules/sys_watch_usb.c
     modules/sys_request_server.c
+    modules/net_ipv6_wait_dynamic_addr.c
     ${NCD_ADDITIONAL_SOURCES}
 )
 target_link_libraries(badvpn-ncd system flow flowextra dhcpclient arpprobe ncdconfig ncdvalue udevmonitor ncdinterfacemonitor)

ncd/modules/modules.h

@@ -90,6 +90,7 @@ extern const struct NCDModuleGroup ncdmodule_sys_evdev;
 extern const struct NCDModuleGroup ncdmodule_sys_watch_directory;
 #endif
 extern const struct NCDModuleGroup ncdmodule_sys_request_server;
+extern const struct NCDModuleGroup ncdmodule_net_ipv6_wait_dynamic_addr;
 
 static const struct NCDModuleGroup *ncd_modules[] = {
     &ncdmodule_var,
@@ -148,6 +149,7 @@ static const struct NCDModuleGroup *ncd_modules[] = {
     &ncdmodule_sys_watch_directory,
 #endif
     &ncdmodule_sys_request_server,
+    &ncdmodule_net_ipv6_wait_dynamic_addr,
     NULL
 };
 

ncd/modules/net_ipv6_wait_dynamic_addr.c

@@ -0,0 +1,205 @@
+/**
+ * @file net_ipv6_wait_dynamic_addr.c
+ * @author Ambroz Bizjak <ambrop7@gmail.com>
+ * 
+ * @section LICENSE
+ * 
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions are met:
+ * 1. Redistributions of source code must retain the above copyright
+ *    notice, this list of conditions and the following disclaimer.
+ * 2. Redistributions in binary form must reproduce the above copyright
+ *    notice, this list of conditions and the following disclaimer in the
+ *    documentation and/or other materials provided with the distribution.
+ * 3. Neither the name of the author nor the
+ *    names of its contributors may be used to endorse or promote products
+ *    derived from this software without specific prior written permission.
+ * 
+ * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS" AND
+ * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
+ * WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
+ * DISCLAIMED. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY
+ * DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
+ * (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
+ * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND
+ * ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+ * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
+ * SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ * 
+ * @section DESCRIPTION
+ * 
+ * Synopsis:
+ *   net.ipv6.wait_dynamic_addr(string ifname)
+ * 
+ * Description:
+ *   Waits for a dynamic IPv6 address to be obtained on the interface,
+ *   and goes up when it is obtained.
+ *   If the address is subsequently lost, goes back down and again waits
+ *   for an address.
+ * 
+ * Variables:
+ *   string addr - dynamic address obtained on the interface, as formatted
+ *                 by getnameinfo(..., NI_NUMERICHOST)
+ *   string prefix - prefix length
+ */
+
+#include <stdlib.h>
+#include <string.h>
+#include <stdio.h>
+
+#include <misc/get_iface_info.h>
+#include <misc/ipaddr6.h>
+#include <ncd/NCDModule.h>
+#include <ncd/NCDInterfaceMonitor.h>
+
+#include <generated/blog_channel_ncd_net_ipv6_wait_dynamic_addr.h>
+
+#define ModuleLog(i, ...) NCDModuleInst_Backend_Log((i), BLOG_CURRENT_CHANNEL, __VA_ARGS__)
+
+struct instance {
+    NCDModuleInst *i;
+    NCDInterfaceMonitor monitor;
+    struct ipv6_ifaddr ifaddr;
+    int up;
+};
+
+static void instance_free (struct instance *o);
+
+static void monitor_handler (struct instance *o, struct NCDInterfaceMonitor_event event)
+{
+    if (!o->up && event.event == NCDIFMONITOR_EVENT_IPV6_ADDR_ADDED && (event.u.ipv6_addr.addr_flags & NCDIFMONITOR_ADDR_FLAG_DYNAMIC)) {
+        // rememeber address, set up
+        o->ifaddr = event.u.ipv6_addr.addr;
+        o->up = 1;
+        
+        // signal up
+        NCDModuleInst_Backend_Up(o->i);
+    }
+    else if (o->up && event.event == NCDIFMONITOR_EVENT_IPV6_ADDR_REMOVED && !memcmp(event.u.ipv6_addr.addr.addr, o->ifaddr.addr, 16) && event.u.ipv6_addr.addr.prefix == o->ifaddr.prefix) {
+        // set not up
+        o->up = 0;
+        
+        // signal down
+        NCDModuleInst_Backend_Down(o->i);
+    }
+}
+
+static void monitor_handler_error (struct instance *o)
+{
+    ModuleLog(o->i, BLOG_ERROR, "monitor error");
+    
+    NCDModuleInst_Backend_SetError(o->i);
+    instance_free(o);
+}
+
+static void func_new (NCDModuleInst *i)
+{
+    // allocate instance
+    struct instance *o = malloc(sizeof(*o));
+    if (!o) {
+        ModuleLog(i, BLOG_ERROR, "failed to allocate instance");
+        goto fail0;
+    }
+    o->i = i;
+    NCDModuleInst_Backend_SetUser(i, o);
+    
+    // read arguments
+    NCDValue *ifname_arg;
+    if (!NCDValue_ListRead(i->args, 1, &ifname_arg)) {
+        ModuleLog(o->i, BLOG_ERROR, "wrong arity");
+        goto fail1;
+    }
+    if (NCDValue_Type(ifname_arg) != NCDVALUE_STRING) {
+        ModuleLog(o->i, BLOG_ERROR, "wrong type");
+        goto fail1;
+    }
+    const char *ifname = NCDValue_StringValue(ifname_arg);
+    
+    // get interface index
+    int ifindex;
+    if (!get_iface_info(ifname, NULL, NULL, &ifindex)) {
+        ModuleLog(o->i, BLOG_ERROR, "failed to get interface index");
+        goto fail1;
+    }
+    
+    // init monitor
+    if (!NCDInterfaceMonitor_Init(&o->monitor, ifindex, NCDIFMONITOR_WATCH_IPV6_ADDR, i->params->reactor, o, (NCDInterfaceMonitor_handler)monitor_handler, (NCDInterfaceMonitor_handler_error)monitor_handler_error)) {
+        ModuleLog(o->i, BLOG_ERROR, "NCDInterfaceMonitor_Init failed");
+        goto fail1;
+    }
+    
+    // set not up
+    o->up = 0;
+    return;
+    
+fail1:
+    free(o);
+fail0:
+    NCDModuleInst_Backend_SetError(i);
+    NCDModuleInst_Backend_Dead(i);
+}
+
+static void instance_free (struct instance *o)
+{
+    NCDModuleInst *i = o->i;
+    
+    // free monitor
+    NCDInterfaceMonitor_Free(&o->monitor);
+    
+    // free instance
+    free(o);
+    
+    NCDModuleInst_Backend_Dead(i);
+}
+
+static void func_die (void *vo)
+{
+    struct instance *o = vo;
+    instance_free(o);
+}
+
+static int func_getvar (void *vo, const char *name, NCDValue *out)
+{
+    struct instance *o = vo;
+    ASSERT(o->up)
+    
+    if (!strcmp(name, "addr")) {
+        char str[IPADDR6_PRINT_MAX];
+        if (!ipaddr6_print_addr(o->ifaddr.addr, str)) {
+            ModuleLog(o->i, BLOG_ERROR, "ipaddr6_print_addr failed");
+            return 0;
+        }
+        if (!NCDValue_InitString(out, str)) {
+            ModuleLog(o->i, BLOG_ERROR, "NCDValue_InitString failed");
+            return 0;
+        }
+        return 1;
+    }
+    
+    if (!strcmp(name, "prefix")) {
+        char str[10];
+        sprintf(str, "%d", o->ifaddr.prefix);
+        if (!NCDValue_InitString(out, str)) {
+            ModuleLog(o->i, BLOG_ERROR, "NCDValue_InitString failed");
+            return 0;
+        }
+        return 1;
+    }
+    
+    return 0;
+}
+
+static const struct NCDModule modules[] = {
+    {
+        .type = "net.ipv6.wait_dynamic_addr",
+        .func_new = func_new,
+        .func_die = func_die,
+        .func_getvar = func_getvar
+    }, {
+        .type = NULL
+    }
+};
+
+const struct NCDModuleGroup ncdmodule_net_ipv6_wait_dynamic_addr = {
+    .modules = modules
+};