VPN: refactor few JNI methods for the usage of legacy VPN.

Now default routes are handled in JNI instead of VpnBuilder.

Change-Id: Ib026bba6793b64aae0f8356df3d2aaae489d08b4

1 files changed, 147 insertions, 114 deletions

diff --git a/services/jni/com_android_server_connectivity_Vpn.cpp b/services/jni/com_android_server_connectivity_Vpn.cpp
index ae7fbfe..a0ea92b 100644
--- a/services/jni/com_android_server_connectivity_Vpn.cpp
+++ b/services/jni/com_android_server_connectivity_Vpn.cpp
@@ -42,6 +42,9 @@
 namespace android
 {
 
+static int inet4 = -1;
+static int inet6 = -1;
+
 static inline in_addr_t *as_in_addr(sockaddr *sa) {
     return &((sockaddr_in *)sa)->sin_addr.s_addr;
 }
@@ -51,11 +54,9 @@ static inline in_addr_t *as_in_addr(sockaddr *sa) {
 #define SYSTEM_ERROR -1
 #define BAD_ARGUMENT -2
 
-static int create_interface(int mtu, char *name, int *index)
+static int create_interface(int mtu)
 {
-    int tun = open("/dev/tun", O_RDWR);
-    int inet4 = socket(AF_INET, SOCK_DGRAM, 0);
-    int flags;
+    int tun = open("/dev/tun", O_RDWR | O_NONBLOCK);
 
     ifreq ifr4;
     memset(&ifr4, 0, sizeof(ifr4));
@@ -81,38 +82,45 @@ static int create_interface(int mtu, char *name, int *index)
         goto error;
     }
 
-    // Get interface index.
-    if (ioctl(inet4, SIOGIFINDEX, &ifr4)) {
-        LOGE("Cannot get index of %s: %s", ifr4.ifr_name, strerror(errno));
-        goto error;
-    }
-
-    // Make it non-blocking.
-    flags = fcntl(tun, F_GETFL, 0);
-    if (flags == -1 || fcntl(tun, F_SETFL, flags | O_NONBLOCK)) {
-        LOGE("Cannot set non-blocking on %s: %s", ifr4.ifr_name, strerror(errno));
-        goto error;
-    }
-
-    strcpy(name, ifr4.ifr_name);
-    *index = ifr4.ifr_ifindex;
-    close(inet4);
     return tun;
 
 error:
     close(tun);
-    close(inet4);
     return SYSTEM_ERROR;
 }
 
-static int set_addresses(const char *name, int index, const char *addresses)
+static int get_interface_name(char *name, int tun)
+{
+    ifreq ifr4;
+    if (ioctl(tun, TUNGETIFF, &ifr4)) {
+        LOGE("Cannot get interface name: %s", strerror(errno));
+        return SYSTEM_ERROR;
+    }
+    strncpy(name, ifr4.ifr_name, IFNAMSIZ);
+    return 0;
+}
+
+static int get_interface_index(const char *name)
+{
+    ifreq ifr4;
+    strncpy(ifr4.ifr_name, name, IFNAMSIZ);
+    if (ioctl(inet4, SIOGIFINDEX, &ifr4)) {
+        LOGE("Cannot get index of %s: %s", name, strerror(errno));
+        return SYSTEM_ERROR;
+    }
+    return ifr4.ifr_ifindex;
+}
+
+static int set_addresses(const char *name, const char *addresses)
 {
-    int inet4 = socket(AF_INET, SOCK_DGRAM, 0);
-    int inet6 = socket(AF_INET6, SOCK_DGRAM, 0);
+    int index = get_interface_index(name);
+    if (index < 0) {
+        return index;
+    }
 
     ifreq ifr4;
     memset(&ifr4, 0, sizeof(ifr4));
-    strcpy(ifr4.ifr_name, name);
+    strncpy(ifr4.ifr_name, name, IFNAMSIZ);
     ifr4.ifr_addr.sa_family = AF_INET;
 
     in6_ifreq ifr6;
@@ -121,7 +129,6 @@ static int set_addresses(const char *name, int index, const char *addresses)
 
     char address[65];
     int prefix;
-
     int chars;
     int count = 0;
 
@@ -164,7 +171,7 @@ static int set_addresses(const char *name, int index, const char *addresses)
                 break;
             }
         }
-        LOGV("Address added on %s: %s/%d", name, address, prefix);
+        LOGD("Address added on %s: %s/%d", name, address, prefix);
         ++count;
     }
 
@@ -177,15 +184,15 @@ static int set_addresses(const char *name, int index, const char *addresses)
         count = BAD_ARGUMENT;
     }
 
-    close(inet4);
-    close(inet6);
     return count;
 }
 
-static int set_routes(const char *name, int index, const char *routes)
+static int set_routes(const char *name, const char *routes)
 {
-    int inet4 = socket(AF_INET, SOCK_DGRAM, 0);
-    int inet6 = socket(AF_INET6, SOCK_DGRAM, 0);
+    int index = get_interface_index(name);
+    if (index < 0) {
+        return index;
+    }
 
     rtentry rt4;
     memset(&rt4, 0, sizeof(rt4));
@@ -201,7 +208,6 @@ static int set_routes(const char *name, int index, const char *routes)
 
     char address[65];
     int prefix;
-
     int chars;
     int count = 0;
 
@@ -211,32 +217,50 @@ static int set_routes(const char *name, int index, const char *routes)
         if (strchr(address, ':')) {
             // Add an IPv6 route.
             if (inet_pton(AF_INET6, address, &rt6.rtmsg_dst) != 1 ||
-                    prefix < 1 || prefix > 128) {
+                    prefix < 0 || prefix > 128) {
                 count = BAD_ARGUMENT;
                 break;
             }
 
-            rt6.rtmsg_dst_len = prefix;
+            rt6.rtmsg_dst_len = prefix ? prefix : 1;
             if (ioctl(inet6, SIOCADDRT, &rt6) && errno != EEXIST) {
                 count = (errno == EINVAL) ? BAD_ARGUMENT : SYSTEM_ERROR;
                 break;
             }
+
+            if (!prefix) {
+                // Split the route instead of replacing the default route.
+                rt6.rtmsg_dst.s6_addr[0] ^= 0x80;
+                if (ioctl(inet6, SIOCADDRT, &rt6) && errno != EEXIST) {
+                    count = SYSTEM_ERROR;
+                    break;
+                }
+            }
         } else {
             // Add an IPv4 route.
             if (inet_pton(AF_INET, address, as_in_addr(&rt4.rt_dst)) != 1 ||
-                    prefix < 1 || prefix > 32) {
+                    prefix < 0 || prefix > 32) {
                 count = BAD_ARGUMENT;
                 break;
             }
 
-            in_addr_t mask = prefix ? (~0 << (32 - prefix)) : 0;
+            in_addr_t mask = prefix ? (~0 << (32 - prefix)) : 1;
             *as_in_addr(&rt4.rt_genmask) = htonl(mask);
             if (ioctl(inet4, SIOCADDRT, &rt4) && errno != EEXIST) {
                 count = (errno == EINVAL) ? BAD_ARGUMENT : SYSTEM_ERROR;
                 break;
             }
+
+            if (!prefix) {
+                // Split the route instead of replacing the default route.
+                *as_in_addr(&rt4.rt_dst) ^= htonl(0x80000000);
+                if (ioctl(inet4, SIOCADDRT, &rt4) && errno != EEXIST) {
+                    count = SYSTEM_ERROR;
+                    break;
+                }
+            }
         }
-        LOGV("Route added on %s: %s/%d", name, address, prefix);
+        LOGD("Route added on %s: %s/%d", name, address, prefix);
         ++count;
     }
 
@@ -250,43 +274,24 @@ static int set_routes(const char *name, int index, const char *routes)
         count = BAD_ARGUMENT;
     }
 
-    close(inet4);
-    close(inet6);
     return count;
 }
 
-static int get_interface_name(char *name, int tun)
-{
-    ifreq ifr4;
-    if (ioctl(tun, TUNGETIFF, &ifr4)) {
-        LOGE("Cannot get interface name: %s", strerror(errno));
-        return SYSTEM_ERROR;
-    }
-    strcpy(name, ifr4.ifr_name);
-    return 0;
-}
-
 static int reset_interface(const char *name)
 {
-    int inet4 = socket(AF_INET, SOCK_DGRAM, 0);
-
     ifreq ifr4;
-    ifr4.ifr_flags = 0;
     strncpy(ifr4.ifr_name, name, IFNAMSIZ);
+    ifr4.ifr_flags = 0;
 
     if (ioctl(inet4, SIOCSIFFLAGS, &ifr4) && errno != ENODEV) {
         LOGE("Cannot reset %s: %s", name, strerror(errno));
-        close(inet4);
         return SYSTEM_ERROR;
     }
-    close(inet4);
     return 0;
 }
 
 static int check_interface(const char *name)
 {
-    int inet4 = socket(AF_INET, SOCK_DGRAM, 0);
-
     ifreq ifr4;
     strncpy(ifr4.ifr_name, name, IFNAMSIZ);
     ifr4.ifr_flags = 0;
@@ -294,7 +299,6 @@ static int check_interface(const char *name)
     if (ioctl(inet4, SIOCGIFFLAGS, &ifr4) && errno != ENODEV) {
         LOGE("Cannot check %s: %s", name, strerror(errno));
     }
-    close(inet4);
     return ifr4.ifr_flags;
 }
 
@@ -318,86 +322,108 @@ static void throwException(JNIEnv *env, int error, const char *message)
     }
 }
 
-static jint establish(JNIEnv *env, jobject thiz,
-        jint mtu, jstring jAddresses, jstring jRoutes)
+static jint createInterface(JNIEnv *env, jobject thiz, jint mtu)
 {
-    char name[IFNAMSIZ];
-    int index;
-    int tun = create_interface(mtu, name, &index);
+    int tun = create_interface(mtu);
     if (tun < 0) {
         throwException(env, tun, "Cannot create interface");
         return -1;
     }
-    LOGD("%s is created", name);
+    return tun;
+}
 
-    const char *addresses;
-    const char *routes;
-    int count;
+static jstring getInterfaceName(JNIEnv *env, jobject thiz, jint tun)
+{
+    char name[IFNAMSIZ];
+    if (get_interface_name(name, tun) < 0) {
+        throwException(env, SYSTEM_ERROR, "Cannot get interface name");
+        return NULL;
+    }
+    return env->NewStringUTF(name);
+}
 
-    // Addresses are required.
+static jint setAddresses(JNIEnv *env, jobject thiz, jstring jName,
+        jstring jAddresses)
+{
+    const char *name = NULL;
+    const char *addresses = NULL;
+    int count = -1;
+
+    name = jName ? env->GetStringUTFChars(jName, NULL) : NULL;
+    if (!name) {
+        jniThrowNullPointerException(env, "name");
+        goto error;
+    }
     addresses = jAddresses ? env->GetStringUTFChars(jAddresses, NULL) : NULL;
     if (!addresses) {
-        jniThrowNullPointerException(env, "address");
+        jniThrowNullPointerException(env, "addresses");
         goto error;
     }
-    count = set_addresses(name, index, addresses);
-    env->ReleaseStringUTFChars(jAddresses, addresses);
-    if (count <= 0) {
+    count = set_addresses(name, addresses);
+    if (count < 0) {
         throwException(env, count, "Cannot set address");
-        goto error;
+        count = -1;
     }
-    LOGD("Configured %d address(es) on %s", count, name);
-
-    // Routes are optional.
-    routes = jRoutes ? env->GetStringUTFChars(jRoutes, NULL) : NULL;
-    if (routes) {
-        count = set_routes(name, index, routes);
-        env->ReleaseStringUTFChars(jRoutes, routes);
-        if (count < 0) {
-            throwException(env, count, "Cannot set route");
-            goto error;
-        }
-        LOGD("Configured %d route(s) on %s", count, name);
-    }
-
-    return tun;
 
 error:
-    close(tun);
-    LOGD("%s is destroyed", name);
-    return -1;
+    if (name) {
+        env->ReleaseStringUTFChars(jName, name);
+    }
+    if (addresses) {
+        env->ReleaseStringUTFChars(jAddresses, addresses);
+    }
+    return count;
 }
 
-static jstring getName(JNIEnv *env, jobject thiz, jint fd)
+static jint setRoutes(JNIEnv *env, jobject thiz, jstring jName,
+        jstring jRoutes)
 {
-    char name[IFNAMSIZ];
-    if (get_interface_name(name, fd) < 0) {
-        throwException(env, SYSTEM_ERROR, "Cannot get interface name");
-        return NULL;
+    const char *name = NULL;
+    const char *routes = NULL;
+    int count = -1;
+
+    name = jName ? env->GetStringUTFChars(jName, NULL) : NULL;
+    if (!name) {
+        jniThrowNullPointerException(env, "name");
+        goto error;
     }
-    return env->NewStringUTF(name);
+    routes = jRoutes ? env->GetStringUTFChars(jRoutes, NULL) : NULL;
+    if (!routes) {
+        jniThrowNullPointerException(env, "routes");
+        goto error;
+    }
+    count = set_routes(name, routes);
+    if (count < 0) {
+        throwException(env, count, "Cannot set address");
+        count = -1;
+    }
+
+error:
+    if (name) {
+        env->ReleaseStringUTFChars(jName, name);
+    }
+    if (routes) {
+        env->ReleaseStringUTFChars(jRoutes, routes);
+    }
+    return count;
 }
 
-static void reset(JNIEnv *env, jobject thiz, jstring jName)
+static void resetInterface(JNIEnv *env, jobject thiz, jstring jName)
 {
-    const char *name = jName ?
-            env->GetStringUTFChars(jName, NULL) : NULL;
+    const char *name = jName ? env->GetStringUTFChars(jName, NULL) : NULL;
     if (!name) {
         jniThrowNullPointerException(env, "name");
         return;
     }
     if (reset_interface(name) < 0) {
         throwException(env, SYSTEM_ERROR, "Cannot reset interface");
-    } else {
-        LOGD("%s is deactivated", name);
     }
     env->ReleaseStringUTFChars(jName, name);
 }
 
-static jint check(JNIEnv *env, jobject thiz, jstring jName)
+static jint checkInterface(JNIEnv *env, jobject thiz, jstring jName)
 {
-    const char *name = jName ?
-            env->GetStringUTFChars(jName, NULL) : NULL;
+    const char *name = jName ? env->GetStringUTFChars(jName, NULL) : NULL;
     if (!name) {
         jniThrowNullPointerException(env, "name");
         return 0;
@@ -407,10 +433,9 @@ static jint check(JNIEnv *env, jobject thiz, jstring jName)
     return flags;
 }
 
-static void protect(JNIEnv *env, jobject thiz, jint fd, jstring jName)
+static void protectSocket(JNIEnv *env, jobject thiz, jint fd, jstring jName)
 {
-    const char *name = jName ?
-            env->GetStringUTFChars(jName, NULL) : NULL;
+    const char *name = jName ? env->GetStringUTFChars(jName, NULL) : NULL;
     if (!name) {
         jniThrowNullPointerException(env, "name");
         return;
@@ -424,15 +449,23 @@ static void protect(JNIEnv *env, jobject thiz, jint fd, jstring jName)
 //------------------------------------------------------------------------------
 
 static JNINativeMethod gMethods[] = {
-    {"nativeEstablish", "(ILjava/lang/String;Ljava/lang/String;)I", (void *)establish},
-    {"nativeGetName", "(I)Ljava/lang/String;", (void *)getName},
-    {"nativeReset", "(Ljava/lang/String;)V", (void *)reset},
-    {"nativeCheck", "(Ljava/lang/String;)I", (void *)check},
-    {"nativeProtect", "(ILjava/lang/String;)V", (void *)protect},
+    {"jniCreateInterface", "(I)I", (void *)createInterface},
+    {"jniGetInterfaceName", "(I)Ljava/lang/String;", (void *)getInterfaceName},
+    {"jniSetAddresses", "(Ljava/lang/String;Ljava/lang/String;)I", (void *)setAddresses},
+    {"jniSetRoutes", "(Ljava/lang/String;Ljava/lang/String;)I", (void *)setRoutes},
+    {"jniResetInterface", "(Ljava/lang/String;)V", (void *)resetInterface},
+    {"jniCheckInterface", "(Ljava/lang/String;)I", (void *)checkInterface},
+    {"jniProtectSocket", "(ILjava/lang/String;)V", (void *)protectSocket},
 };
 
 int register_android_server_connectivity_Vpn(JNIEnv *env)
 {
+    if (inet4 == -1) {
+        inet4 = socket(AF_INET, SOCK_DGRAM, 0);
+    }
+    if (inet6 == -1) {
+        inet6 = socket(AF_INET6, SOCK_DGRAM, 0);
+    }
     return jniRegisterNativeMethods(env, "com/android/server/connectivity/Vpn",
             gMethods, NELEM(gMethods));
 }