vlan_init.c

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#include "includes.h"

#include "hostapd.h"
#include "driver_i.h"
#include "vlan_init.h"


#ifdef CONFIG_FULL_DYNAMIC_VLAN

#include <net/if.h>
#include <sys/ioctl.h>
#include <linux/sockios.h>
#include <linux/if_vlan.h>
#include <linux/if_bridge.h>

#include "drivers/priv_netlink.h"
#include "eloop.h"


struct full_dynamic_vlan {
        int s; /* socket on which to listen for new/removed interfaces. */
};


static int ifconfig_helper(const char *if_name, int up)
{
        int fd;
        struct ifreq ifr;

        if ((fd = socket(AF_INET, SOCK_STREAM, 0)) < 0) {
                perror("socket[AF_INET,SOCK_STREAM]");
                return -1;
        }

        os_memset(&ifr, 0, sizeof(ifr));
        os_strlcpy(ifr.ifr_name, if_name, IFNAMSIZ);

        if (ioctl(fd, SIOCGIFFLAGS, &ifr) != 0) {
                perror("ioctl[SIOCGIFFLAGS]");
                close(fd);
                return -1;
        }

        if (up)
                ifr.ifr_flags |= IFF_UP;
        else
                ifr.ifr_flags &= ~IFF_UP;

        if (ioctl(fd, SIOCSIFFLAGS, &ifr) != 0) {
                perror("ioctl[SIOCSIFFLAGS]");
                close(fd);
                return -1;
        }

        close(fd);
        return 0;
}


static int ifconfig_up(const char *if_name)
{
        return ifconfig_helper(if_name, 1);
}


static int ifconfig_down(const char *if_name)
{
        return ifconfig_helper(if_name, 0);
}


/*
 * These are only available in recent linux headers (without the leading
 * underscore).
 */
#define _GET_VLAN_REALDEV_NAME_CMD      8
#define _GET_VLAN_VID_CMD               9

/* This value should be 256 ONLY. If it is something else, then hostapd
 * might crash!, as this value has been hard-coded in 2.4.x kernel
 * bridging code.
 */
#define MAX_BR_PORTS                    256

static int br_delif(const char *br_name, const char *if_name)
{
        int fd;
        struct ifreq ifr;
        unsigned long args[2];
        int if_index;

        if ((fd = socket(AF_INET, SOCK_STREAM, 0)) < 0) {
                perror("socket[AF_INET,SOCK_STREAM]");
                return -1;
        }

        if_index = if_nametoindex(if_name);

        if (if_index == 0) {
                printf("Failure determining interface index for '%s'\n",
                       if_name);
                close(fd);
                return -1;
        }

        args[0] = BRCTL_DEL_IF;
        args[1] = if_index;

        os_strlcpy(ifr.ifr_name, br_name, sizeof(ifr.ifr_name));
        ifr.ifr_data = (__caddr_t) args;

        if (ioctl(fd, SIOCDEVPRIVATE, &ifr) < 0 && errno != EINVAL) {
                /* No error if interface already removed. */
                perror("ioctl[SIOCDEVPRIVATE,BRCTL_DEL_IF]");
                close(fd);
                return -1;
        }

        close(fd);
        return 0;
}


/*
        Add interface 'if_name' to the bridge 'br_name'

        returns -1 on error
        returns 1 if the interface is already part of the bridge
        returns 0 otherwise
*/
static int br_addif(const char *br_name, const char *if_name)
{
        int fd;
        struct ifreq ifr;
        unsigned long args[2];
        int if_index;

        if ((fd = socket(AF_INET, SOCK_STREAM, 0)) < 0) {
                perror("socket[AF_INET,SOCK_STREAM]");
                return -1;
        }

        if_index = if_nametoindex(if_name);

        if (if_index == 0) {
                printf("Failure determining interface index for '%s'\n",
                       if_name);
                close(fd);
                return -1;
        }

        args[0] = BRCTL_ADD_IF;
        args[1] = if_index;

        os_strlcpy(ifr.ifr_name, br_name, sizeof(ifr.ifr_name));
        ifr.ifr_data = (__caddr_t) args;

        if (ioctl(fd, SIOCDEVPRIVATE, &ifr) < 0) {
                if (errno == EBUSY) {
                        /* The interface is already added. */
                        close(fd);
                        return 1;
                }

                perror("ioctl[SIOCDEVPRIVATE,BRCTL_ADD_IF]");
                close(fd);
                return -1;
        }

        close(fd);
        return 0;
}


static int br_delbr(const char *br_name)
{
        int fd;
        unsigned long arg[2];

        if ((fd = socket(AF_INET, SOCK_STREAM, 0)) < 0) {
                perror("socket[AF_INET,SOCK_STREAM]");
                return -1;
        }

        arg[0] = BRCTL_DEL_BRIDGE;
        arg[1] = (unsigned long) br_name;

        if (ioctl(fd, SIOCGIFBR, arg) < 0 && errno != ENXIO) {
                /* No error if bridge already removed. */
                perror("ioctl[BRCTL_DEL_BRIDGE]");
                close(fd);
                return -1;
        }

        close(fd);
        return 0;
}


/*
        Add a bridge with the name 'br_name'.

        returns -1 on error
        returns 1 if the bridge already exists
        returns 0 otherwise
*/
static int br_addbr(const char *br_name)
{
        int fd;
        unsigned long arg[2];

        if ((fd = socket(AF_INET, SOCK_STREAM, 0)) < 0) {
                perror("socket[AF_INET,SOCK_STREAM]");
                return -1;
        }

        arg[0] = BRCTL_ADD_BRIDGE;
        arg[1] = (unsigned long) br_name;

        if (ioctl(fd, SIOCGIFBR, arg) < 0) {
                if (errno == EEXIST) {
                        /* The bridge is already added. */
                        close(fd);
                        return 1;
                } else {
                        perror("ioctl[BRCTL_ADD_BRIDGE]");
                        close(fd);
                        return -1;
                }
        }

        close(fd);
        return 0;
}


static int br_getnumports(const char *br_name)
{
        int fd;
        int i;
        int port_cnt = 0;
        unsigned long arg[4];
        int ifindices[MAX_BR_PORTS];
        struct ifreq ifr;

        if ((fd = socket(AF_INET, SOCK_STREAM, 0)) < 0) {
                perror("socket[AF_INET,SOCK_STREAM]");
                return -1;
        }

        arg[0] = BRCTL_GET_PORT_LIST;
        arg[1] = (unsigned long) ifindices;
        arg[2] = MAX_BR_PORTS;
        arg[3] = 0;

        os_memset(ifindices, 0, sizeof(ifindices));
        os_strlcpy(ifr.ifr_name, br_name, sizeof(ifr.ifr_name));
        ifr.ifr_data = (__caddr_t) arg;

        if (ioctl(fd, SIOCDEVPRIVATE, &ifr) < 0) {
                perror("ioctl[SIOCDEVPRIVATE,BRCTL_GET_PORT_LIST]");
                close(fd);
                return -1;
        }

        for (i = 1; i < MAX_BR_PORTS; i++) {
                if (ifindices[i] > 0) {
                        port_cnt++;
                }
        }

        close(fd);
        return port_cnt;
}


static int vlan_rem(const char *if_name)
{
        int fd;
        struct vlan_ioctl_args if_request;

        if ((os_strlen(if_name) + 1) > sizeof(if_request.device1)) {
                fprintf(stderr, "Interface name to long.\n");
                return -1;
        }

        if ((fd = socket(AF_INET, SOCK_STREAM, 0)) < 0) {
                perror("socket[AF_INET,SOCK_STREAM]");
                return -1;
        }

        os_memset(&if_request, 0, sizeof(if_request));

        os_strlcpy(if_request.device1, if_name, sizeof(if_request.device1));
        if_request.cmd = DEL_VLAN_CMD;

        if (ioctl(fd, SIOCSIFVLAN, &if_request) < 0) {
                perror("ioctl[SIOCSIFVLAN,DEL_VLAN_CMD]");
                close(fd);
                return -1;
        }

        close(fd);
        return 0;
}


/*
        Add a vlan interface with VLAN ID 'vid' and tagged interface
        'if_name'.

        returns -1 on error
        returns 1 if the interface already exists
        returns 0 otherwise
*/
static int vlan_add(const char *if_name, int vid)
{
        int fd;
        struct vlan_ioctl_args if_request;

        ifconfig_up(if_name);

        if ((os_strlen(if_name) + 1) > sizeof(if_request.device1)) {
                fprintf(stderr, "Interface name to long.\n");
                return -1;
        }

        if ((fd = socket(AF_INET, SOCK_STREAM, 0)) < 0) {
                perror("socket[AF_INET,SOCK_STREAM]");
                return -1;
        }

        os_memset(&if_request, 0, sizeof(if_request));

        /* Determine if a suitable vlan device already exists. */

        os_snprintf(if_request.device1, sizeof(if_request.device1), "vlan%d",
                    vid);

        if_request.cmd = _GET_VLAN_VID_CMD;

        if (ioctl(fd, SIOCSIFVLAN, &if_request) == 0) {

                if (if_request.u.VID == vid) {
                        if_request.cmd = _GET_VLAN_REALDEV_NAME_CMD;

                        if (ioctl(fd, SIOCSIFVLAN, &if_request) == 0 &&
                            os_strncmp(if_request.u.device2, if_name,
                                       sizeof(if_request.u.device2)) == 0) {
                                close(fd);
                                return 1;
                        }
                }
        }

        /* A suitable vlan device does not already exist, add one. */

        os_memset(&if_request, 0, sizeof(if_request));
        os_strlcpy(if_request.device1, if_name, sizeof(if_request.device1));
        if_request.u.VID = vid;
        if_request.cmd = ADD_VLAN_CMD;

        if (ioctl(fd, SIOCSIFVLAN, &if_request) < 0) {
                perror("ioctl[SIOCSIFVLAN,ADD_VLAN_CMD]");
                close(fd);
                return -1;
        }

        close(fd);
        return 0;
}


static int vlan_set_name_type(unsigned int name_type)
{
        int fd;
        struct vlan_ioctl_args if_request;

        if ((fd = socket(AF_INET, SOCK_STREAM, 0)) < 0) {
                perror("socket[AF_INET,SOCK_STREAM]");
                return -1;
        }

        os_memset(&if_request, 0, sizeof(if_request));

        if_request.u.name_type = name_type;
        if_request.cmd = SET_VLAN_NAME_TYPE_CMD;
        if (ioctl(fd, SIOCSIFVLAN, &if_request) < 0) {
                perror("ioctl[SIOCSIFVLAN,SET_VLAN_NAME_TYPE_CMD]");
                close(fd);
                return -1;
        }

        close(fd);
        return 0;
}


static void vlan_newlink(char *ifname, struct hostapd_data *hapd)
{
        char vlan_ifname[IFNAMSIZ];
        char br_name[IFNAMSIZ];
        struct hostapd_vlan *vlan = hapd->conf->vlan;
        char *tagged_interface = hapd->conf->ssid.vlan_tagged_interface;

        while (vlan) {
                if (os_strcmp(ifname, vlan->ifname) == 0) {

                        os_snprintf(br_name, sizeof(br_name), "brvlan%d",
                                    vlan->vlan_id);

                        if (!br_addbr(br_name))
                                vlan->clean |= DVLAN_CLEAN_BR;

                        ifconfig_up(br_name);

                        if (tagged_interface) {

                                if (!vlan_add(tagged_interface, vlan->vlan_id))
                                        vlan->clean |= DVLAN_CLEAN_VLAN;

                                os_snprintf(vlan_ifname, sizeof(vlan_ifname),
                                            "vlan%d", vlan->vlan_id);

                                if (!br_addif(br_name, vlan_ifname))
                                        vlan->clean |= DVLAN_CLEAN_VLAN_PORT;

                                ifconfig_up(vlan_ifname);
                        }

                        if (!br_addif(br_name, ifname))
                                vlan->clean |= DVLAN_CLEAN_WLAN_PORT;

                        ifconfig_up(ifname);

                        break;
                }
                vlan = vlan->next;
        }
}


static void vlan_dellink(char *ifname, struct hostapd_data *hapd)
{
        char vlan_ifname[IFNAMSIZ];
        char br_name[IFNAMSIZ];
        struct hostapd_vlan *first, *prev, *vlan = hapd->conf->vlan;
        char *tagged_interface = hapd->conf->ssid.vlan_tagged_interface;
        int numports;

        first = prev = vlan;

        while (vlan) {
                if (os_strcmp(ifname, vlan->ifname) == 0) {
                        os_snprintf(br_name, sizeof(br_name), "brvlan%d",
                                    vlan->vlan_id);

                        if (tagged_interface) {
                                os_snprintf(vlan_ifname, sizeof(vlan_ifname),
                                            "vlan%d", vlan->vlan_id);

                                numports = br_getnumports(br_name);
                                if (numports == 1) {
                                        br_delif(br_name, vlan_ifname);

                                        vlan_rem(vlan_ifname);

                                        ifconfig_down(br_name);
                                        br_delbr(br_name);
                                }
                        }

                        if (vlan == first) {
                                hapd->conf->vlan = vlan->next;
                        } else {
                                prev->next = vlan->next;
                        }
                        os_free(vlan);

                        break;
                }
                prev = vlan;
                vlan = vlan->next;
        }
}


static void
vlan_read_ifnames(struct nlmsghdr *h, size_t len, int del,
                  struct hostapd_data *hapd)
{
        struct ifinfomsg *ifi;
        int attrlen, nlmsg_len, rta_len;
        struct rtattr *attr;

        if (len < sizeof(*ifi))
                return;

        ifi = NLMSG_DATA(h);

        nlmsg_len = NLMSG_ALIGN(sizeof(struct ifinfomsg));

        attrlen = h->nlmsg_len - nlmsg_len;
        if (attrlen < 0)
                return;

        attr = (struct rtattr *) (((char *) ifi) + nlmsg_len);

        rta_len = RTA_ALIGN(sizeof(struct rtattr));
        while (RTA_OK(attr, attrlen)) {
                char ifname[IFNAMSIZ + 1];

                if (attr->rta_type == IFLA_IFNAME) {
                        int n = attr->rta_len - rta_len;
                        if (n < 0)
                                break;

                        os_memset(ifname, 0, sizeof(ifname));

                        if ((size_t) n > sizeof(ifname))
                                n = sizeof(ifname);
                        os_memcpy(ifname, ((char *) attr) + rta_len, n);

                        if (del)
                                vlan_dellink(ifname, hapd);
                        else
                                vlan_newlink(ifname, hapd);
                }

                attr = RTA_NEXT(attr, attrlen);
        }
}


static void vlan_event_receive(int sock, void *eloop_ctx, void *sock_ctx)
{
        char buf[8192];
        int left;
        struct sockaddr_nl from;
        socklen_t fromlen;
        struct nlmsghdr *h;
        struct hostapd_data *hapd = eloop_ctx;

        fromlen = sizeof(from);
        left = recvfrom(sock, buf, sizeof(buf), MSG_DONTWAIT,
                        (struct sockaddr *) &from, &fromlen);
        if (left < 0) {
                if (errno != EINTR && errno != EAGAIN)
                        perror("recvfrom(netlink)");
                return;
        }

        h = (struct nlmsghdr *) buf;
        while (left >= (int) sizeof(*h)) {
                int len, plen;

                len = h->nlmsg_len;
                plen = len - sizeof(*h);
                if (len > left || plen < 0) {
                        printf("Malformed netlink message: "
                               "len=%d left=%d plen=%d", len, left, plen);
                        break;
                }

                switch (h->nlmsg_type) {
                case RTM_NEWLINK:
                        vlan_read_ifnames(h, plen, 0, hapd);
                        break;
                case RTM_DELLINK:
                        vlan_read_ifnames(h, plen, 1, hapd);
                        break;
                }

                len = NLMSG_ALIGN(len);
                left -= len;
                h = (struct nlmsghdr *) ((char *) h + len);
        }

        if (left > 0) {
                printf("%d extra bytes in the end of netlink message",
                       left);
        }
}


static struct full_dynamic_vlan *
full_dynamic_vlan_init(struct hostapd_data *hapd)
{
        struct sockaddr_nl local;
        struct full_dynamic_vlan *priv;

        priv = os_zalloc(sizeof(*priv));
        if (priv == NULL)
                return NULL;

        vlan_set_name_type(VLAN_NAME_TYPE_PLUS_VID_NO_PAD);

        priv->s = socket(PF_NETLINK, SOCK_RAW, NETLINK_ROUTE);
        if (priv->s < 0) {
                perror("socket(PF_NETLINK,SOCK_RAW,NETLINK_ROUTE)");
                os_free(priv);
                return NULL;
        }

        os_memset(&local, 0, sizeof(local));
        local.nl_family = AF_NETLINK;
        local.nl_groups = RTMGRP_LINK;
        if (bind(priv->s, (struct sockaddr *) &local, sizeof(local)) < 0) {
                perror("bind(netlink)");
                close(priv->s);
                os_free(priv);
                return NULL;
        }

        if (eloop_register_read_sock(priv->s, vlan_event_receive, hapd, NULL))
        {
                close(priv->s);
                os_free(priv);
                return NULL;
        }

        return priv;
}


static void full_dynamic_vlan_deinit(struct full_dynamic_vlan *priv)
{
        if (priv == NULL)
                return;
        eloop_unregister_read_sock(priv->s);
        close(priv->s);
        os_free(priv);
}
#endif /* CONFIG_FULL_DYNAMIC_VLAN */


int vlan_setup_encryption_dyn(struct hostapd_data *hapd,
                              struct hostapd_ssid *mssid, const char *dyn_vlan)
{
        int i;

        if (dyn_vlan == NULL)
                return 0;

        /* Static WEP keys are set here; IEEE 802.1X and WPA uses their own
         * functions for setting up dynamic broadcast keys. */
        for (i = 0; i < 4; i++) {
                if (mssid->wep.key[i] &&
                    hostapd_set_key(dyn_vlan, hapd, WPA_ALG_WEP, NULL, i,
                                    i == mssid->wep.idx, NULL, 0,
                                    mssid->wep.key[i], mssid->wep.len[i])) {
                        printf("VLAN: Could not set WEP encryption for "
                               "dynamic VLAN.\n");
                        return -1;
                }
        }

        return 0;
}


static int vlan_dynamic_add(struct hostapd_data *hapd,
                            struct hostapd_vlan *vlan)
{
        while (vlan) {
                if (vlan->vlan_id != VLAN_ID_WILDCARD &&
                    hostapd_if_add(hapd, HOSTAPD_IF_VLAN, vlan->ifname, NULL))
                {
                        if (errno != EEXIST) {
                                printf("Could not add VLAN iface: %s: %s\n",
                                       vlan->ifname, strerror(errno));
                                return -1;
                        }
                }

                vlan = vlan->next;
        }

        return 0;
}


static void vlan_dynamic_remove(struct hostapd_data *hapd,
                                struct hostapd_vlan *vlan)
{
        struct hostapd_vlan *next;

        while (vlan) {
                next = vlan->next;

                if (vlan->vlan_id != VLAN_ID_WILDCARD &&
                    hostapd_if_remove(hapd, HOSTAPD_IF_VLAN, vlan->ifname,
                                      NULL)) {
                        printf("Could not remove VLAN iface: %s: %s\n",
                               vlan->ifname, strerror(errno));
                }
#ifdef CONFIG_FULL_DYNAMIC_VLAN
                if (vlan->clean)
                        vlan_dellink(vlan->ifname, hapd);
#endif /* CONFIG_FULL_DYNAMIC_VLAN */

                vlan = next;
        }
}


int vlan_init(struct hostapd_data *hapd)
{
        if (vlan_dynamic_add(hapd, hapd->conf->vlan))
                return -1;

#ifdef CONFIG_FULL_DYNAMIC_VLAN
        hapd->full_dynamic_vlan = full_dynamic_vlan_init(hapd);
#endif /* CONFIG_FULL_DYNAMIC_VLAN */

        return 0;
}


void vlan_deinit(struct hostapd_data *hapd)
{
        vlan_dynamic_remove(hapd, hapd->conf->vlan);

#ifdef CONFIG_FULL_DYNAMIC_VLAN
        full_dynamic_vlan_deinit(hapd->full_dynamic_vlan);
#endif /* CONFIG_FULL_DYNAMIC_VLAN */
}


int vlan_reconfig(struct hostapd_data *hapd, struct hostapd_config *oldconf,
                  struct hostapd_bss_config *oldbss)
{
        vlan_dynamic_remove(hapd, oldbss->vlan);
        if (vlan_dynamic_add(hapd, hapd->conf->vlan))
                return -1;

        return 0;
}


struct hostapd_vlan * vlan_add_dynamic(struct hostapd_data *hapd,
                                       struct hostapd_vlan *vlan,
                                       int vlan_id)
{
        struct hostapd_vlan *n;
        char *ifname, *pos;

        if (vlan == NULL || vlan_id <= 0 || vlan_id > MAX_VLAN_ID ||
            vlan->vlan_id != VLAN_ID_WILDCARD)
                return NULL;

        ifname = os_strdup(vlan->ifname);
        if (ifname == NULL)
                return NULL;
        pos = os_strchr(ifname, '#');
        if (pos == NULL) {
                os_free(ifname);
                return NULL;
        }
        *pos++ = '\0';

        n = os_zalloc(sizeof(*n));
        if (n == NULL) {
                os_free(ifname);
                return NULL;
        }

        n->vlan_id = vlan_id;
        n->dynamic_vlan = 1;

        os_snprintf(n->ifname, sizeof(n->ifname), "%s%d%s", ifname, vlan_id,
                    pos);
        os_free(ifname);

        if (hostapd_if_add(hapd, HOSTAPD_IF_VLAN, n->ifname, NULL)) {
                os_free(n);
                return NULL;
        }

        n->next = hapd->conf->vlan;
        hapd->conf->vlan = n;

        return n;
}


int vlan_remove_dynamic(struct hostapd_data *hapd, int vlan_id)
{
        struct hostapd_vlan *vlan;

        if (vlan_id <= 0 || vlan_id > MAX_VLAN_ID)
                return 1;

        vlan = hapd->conf->vlan;
        while (vlan) {
                if (vlan->vlan_id == vlan_id && vlan->dynamic_vlan > 0) {
                        vlan->dynamic_vlan--;
                        break;
                }
                vlan = vlan->next;
        }

        if (vlan == NULL)
                return 1;

        if (vlan->dynamic_vlan == 0)
                hostapd_if_remove(hapd, HOSTAPD_IF_VLAN, vlan->ifname, NULL);

        return 0;
}