qsap: Add APIs to control and manage bridge interface.

This adds APIs to trigger create, delete, interface up and interface
down commands on bridge interface.
It uses following IOCTLs for sending command to linux kernel:
Add bridge iface: SIOCBRADDBR
Remove bridge iface: SIOCBRDELBR
Mark iface up/down: SIOCGIFFLAGS

CRs-Fixed: 2080924
Change-Id: I3d34dc16e9ca82dc4b550cbc83fa4120c80ad54c

softap/sdk/qsap_api.c

@@ -3330,6 +3330,87 @@ void qsap_set_ini_filename(void)
     return;
 }
 
+// IOCTL command to create and delete bridge interface //
+#ifndef SIOCBRADDBR
+#define SIOCBRADDBR 0x89a0
+#endif
+#ifndef SIOCBRDELBR
+#define SIOCBRDELBR 0x89a1
+#endif
+
+static int linux_set_iface_flags(int sock, const char *ifname, int dev_up)
+{
+    struct ifreq ifr;
+    int ret;
+
+    if (sock < 0)
+        return -1;
+
+    memset(&ifr, 0, sizeof(ifr));
+    strlcpy(ifr.ifr_name, ifname, IFNAMSIZ);
+
+    if (ioctl(sock, SIOCGIFFLAGS, &ifr) != 0) {
+        ret = errno ? -errno : -999;
+        ALOGE("Could not read interface %s flags: %s",
+               ifname, strerror(errno));
+        return ret;
+    }
+
+    if (dev_up) {
+        if (ifr.ifr_flags & IFF_UP)
+            return 0;
+        ifr.ifr_flags |= IFF_UP;
+    } else {
+        if (!(ifr.ifr_flags & IFF_UP))
+            return 0;
+        ifr.ifr_flags &= ~IFF_UP;
+    }
+
+    if (ioctl(sock, SIOCSIFFLAGS, &ifr) != 0) {
+        ret = errno ? -errno : -999;
+        ALOGE("Could not set interface %s flags (%s): %s",
+               ifname, dev_up ? "UP" : "DOWN", strerror(errno));
+        return ret;
+    }
+    return 0;
+}
+
+int qsap_control_bridge(int argc, char ** argv)
+{
+    int br_socket;
+
+    if (argc < 4) {
+        ALOGE("Command not supported");
+        return -1;
+    }
+
+    br_socket = socket(PF_INET, SOCK_DGRAM, 0);
+    if (br_socket < 0) {
+        ALOGE("socket(PF_INET,SOCK_DGRAM): %s",strerror(errno));
+        return -1;
+    }
+    if (!strncmp(argv[2],"create",6)) {
+        if (ioctl(br_socket, SIOCBRADDBR, argv[3]) < 0) {
+            ALOGE("Could not add bridge %s: %s", argv[3], strerror(errno));
+            return -1;
+        }
+    } else if (!strncmp(argv[2],"remove",6)) {
+        if (ioctl(br_socket, SIOCBRDELBR, argv[3]) < 0) {
+            ALOGE("Could not add remove %s: %s", argv[3], strerror(errno));
+            return -1;
+        }
+    } else if (!strncmp(argv[2],"up",2)) {
+        return linux_set_iface_flags(br_socket, argv[3], 1);
+    } else if (!strncmp(argv[2],"down",4)) {
+        return linux_set_iface_flags(br_socket, argv[3], 0);
+    } else {
+        ALOGE("Command %s not handled.", argv[2]);
+        return -1;
+    }
+
+    return 0;
+}
+
 int qsap_add_or_remove_interface(const char *newIface , int createIface)
 {
     const char *wlanIface = "wlan0";

softap/sdk/qsap_api.h

@@ -603,6 +603,7 @@ int qsap_get_mode(s32 *pmode);
 int qsap_prepare_softap(void);
 int qsap_unprepare_softap(void);
 int qsap_is_fst_enabled(void);
+int qsap_control_bridge(int argc, char ** argv);
 
 #if __cplusplus
 };  // extern "C"