Bluetooth: Replace RFCOMM link mode with security level

Change the RFCOMM internals to use the new security levels and remove
the link mode details.

Signed-off-by: Marcel Holtmann <marcel@holtmann.org>

3 files changed, 79 insertions, 31 deletions

diff --git a/include/net/bluetooth/rfcomm.h b/include/net/bluetooth/rfcomm.h
index 71b45f459687..bda68d833ddd 100644
--- a/include/net/bluetooth/rfcomm.h
+++ b/include/net/bluetooth/rfcomm.h
@@ -183,8 +183,8 @@ struct rfcomm_dlc {
         u8            remote_v24_sig;
         u8            mscex;
         u8            out;
-
-        u32           link_mode;
+        u8            sec_level;
+        u8            role_switch;
         u32           defer_setup;
 
         uint          mtu;
@@ -307,7 +307,8 @@ struct rfcomm_pinfo {
         struct bt_sock bt;
         struct rfcomm_dlc   *dlc;
         u8     channel;
-        u32    link_mode;
+        u8     sec_level;
+        u8     role_switch;
 };
 
 int  rfcomm_init_sockets(void);
diff --git a/net/bluetooth/rfcomm/core.c b/net/bluetooth/rfcomm/core.c
index 68f70c5270c6..db83f92d274c 100644
--- a/net/bluetooth/rfcomm/core.c
+++ b/net/bluetooth/rfcomm/core.c
@@ -223,21 +223,11 @@ static int rfcomm_l2sock_create(struct socket **sock)
         return err;
 }
 
-static inline int rfcomm_check_link_mode(struct rfcomm_dlc *d)
+static inline int rfcomm_check_security(struct rfcomm_dlc *d)
 {
         struct sock *sk = d->session->sock->sk;
-        struct l2cap_conn *conn = l2cap_pi(sk)->conn;
 
-        if (d->link_mode & RFCOMM_LM_SECURE)
-                return hci_conn_security(conn->hcon, BT_SECURITY_HIGH);
-
-        if (d->link_mode & RFCOMM_LM_ENCRYPT)
-                return hci_conn_security(conn->hcon, BT_SECURITY_MEDIUM);
-
-        if (d->link_mode & RFCOMM_LM_AUTH)
-                return hci_conn_security(conn->hcon, BT_SECURITY_LOW);
-
-        return 1;
+        return hci_conn_security(l2cap_pi(sk)->conn->hcon, d->sec_level);
 }
 
 /* ---- RFCOMM DLCs ---- */
@@ -390,7 +380,7 @@ static int __rfcomm_dlc_open(struct rfcomm_dlc *d, bdaddr_t *src, bdaddr_t *dst,
         d->cfc = (s->cfc == RFCOMM_CFC_UNKNOWN) ? 0 : s->cfc;
 
         if (s->state == BT_CONNECTED) {
-                if (rfcomm_check_link_mode(d))
+                if (rfcomm_check_security(d))
                         rfcomm_send_pn(s, 1, d);
                 else
                         set_bit(RFCOMM_AUTH_PENDING, &d->flags);
@@ -1192,7 +1182,7 @@ void rfcomm_dlc_accept(struct rfcomm_dlc *d)
         d->state_change(d, 0);
         rfcomm_dlc_unlock(d);
 
-        if (d->link_mode & RFCOMM_LM_MASTER)
+        if (d->role_switch)
                 hci_conn_switch_role(l2cap_pi(sk)->conn->hcon, 0x00);
 
         rfcomm_send_msc(d->session, 1, d->dlci, d->v24_sig);
@@ -1200,7 +1190,7 @@ void rfcomm_dlc_accept(struct rfcomm_dlc *d)
 
 static void rfcomm_check_accept(struct rfcomm_dlc *d)
 {
-        if (rfcomm_check_link_mode(d)) {
+        if (rfcomm_check_security(d)) {
                 if (d->defer_setup) {
                         set_bit(RFCOMM_DEFER_SETUP, &d->flags);
                         rfcomm_dlc_set_timer(d, RFCOMM_AUTH_TIMEOUT);
@@ -1660,7 +1650,7 @@ static void rfcomm_process_connect(struct rfcomm_session *s)
                 d = list_entry(p, struct rfcomm_dlc, list);
                 if (d->state == BT_CONFIG) {
                         d->mtu = s->mtu;
-                        if (rfcomm_check_link_mode(d)) {
+                        if (rfcomm_check_security(d)) {
                                 rfcomm_send_pn(s, 1, d);
                         } else {
                                 set_bit(RFCOMM_AUTH_PENDING, &d->flags);
@@ -1748,10 +1738,6 @@ static inline void rfcomm_process_dlcs(struct rfcomm_session *s)
                                 } else
                                         rfcomm_dlc_accept(d);
                         }
-                        if (d->link_mode & RFCOMM_LM_SECURE) {
-                                struct sock *sk = s->sock->sk;
-                                hci_conn_change_link_key(l2cap_pi(sk)->conn->hcon);
-                        }
                         continue;
                 } else if (test_and_clear_bit(RFCOMM_AUTH_REJECT, &d->flags)) {
                         rfcomm_dlc_clear_timer(d);
@@ -1994,7 +1980,7 @@ static void rfcomm_security_cfm(struct hci_conn *conn, u8 status, u8 encrypt)
                 d = list_entry(p, struct rfcomm_dlc, list);
 
                 if (!status && encrypt == 0x00 &&
-                                (d->link_mode & RFCOMM_LM_ENCRYPT) &&
+                                d->sec_level == BT_SECURITY_HIGH &&
                                         (d->state == BT_CONNECTED ||
                                                 d->state == BT_CONFIG)) {
                         __rfcomm_dlc_close(d, ECONNREFUSED);
diff --git a/net/bluetooth/rfcomm/sock.c b/net/bluetooth/rfcomm/sock.c
index d37a829a81e4..9986ef35c890 100644
--- a/net/bluetooth/rfcomm/sock.c
+++ b/net/bluetooth/rfcomm/sock.c
@@ -261,14 +261,19 @@ static void rfcomm_sock_init(struct sock *sk, struct sock *parent)
 
         if (parent) {
                 sk->sk_type = parent->sk_type;
-                pi->link_mode = rfcomm_pi(parent)->link_mode;
                 pi->dlc->defer_setup = bt_sk(parent)->defer_setup;
+
+                pi->sec_level = rfcomm_pi(parent)->sec_level;
+                pi->role_switch = rfcomm_pi(parent)->role_switch;
         } else {
-                pi->link_mode = 0;
                 pi->dlc->defer_setup = 0;
+
+                pi->sec_level = BT_SECURITY_LOW;
+                pi->role_switch = 0;
         }
 
-        pi->dlc->link_mode = pi->link_mode;
+        pi->dlc->sec_level = pi->sec_level;
+        pi->dlc->role_switch = pi->role_switch;
 }
 
 static struct proto rfcomm_proto = {
@@ -408,7 +413,8 @@ static int rfcomm_sock_connect(struct socket *sock, struct sockaddr *addr, int a
         bacpy(&bt_sk(sk)->dst, &sa->rc_bdaddr);
         rfcomm_pi(sk)->channel = sa->rc_channel;
 
-        d->link_mode = rfcomm_pi(sk)->link_mode;
+        d->sec_level = rfcomm_pi(sk)->sec_level;
+        d->role_switch = rfcomm_pi(sk)->role_switch;
 
         err = rfcomm_dlc_open(d, &bt_sk(sk)->src, &sa->rc_bdaddr, sa->rc_channel);
         if (!err)
@@ -741,7 +747,14 @@ static int rfcomm_sock_setsockopt_old(struct socket *sock, int optname, char __u
                         break;
                 }
 
-                rfcomm_pi(sk)->link_mode = opt;
+                if (opt & RFCOMM_LM_AUTH)
+                        rfcomm_pi(sk)->sec_level = BT_SECURITY_LOW;
+                if (opt & RFCOMM_LM_ENCRYPT)
+                        rfcomm_pi(sk)->sec_level = BT_SECURITY_MEDIUM;
+                if (opt & RFCOMM_LM_SECURE)
+                        rfcomm_pi(sk)->sec_level = BT_SECURITY_HIGH;
+
+                rfcomm_pi(sk)->role_switch = (opt & RFCOMM_LM_MASTER);
                 break;
 
         default:
@@ -756,7 +769,8 @@ static int rfcomm_sock_setsockopt_old(struct socket *sock, int optname, char __u
 static int rfcomm_sock_setsockopt(struct socket *sock, int level, int optname, char __user *optval, int optlen)
 {
         struct sock *sk = sock->sk;
-        int err = 0;
+        struct bt_security sec;
+        int len, err = 0;
         u32 opt;
 
         BT_DBG("sk %p", sk);
@@ -767,6 +781,23 @@ static int rfcomm_sock_setsockopt(struct socket *sock, int level, int optname, c
         lock_sock(sk);
 
         switch (optname) {
+        case BT_SECURITY:
+                sec.level = BT_SECURITY_LOW;
+
+                len = min_t(unsigned int, sizeof(sec), optlen);
+                if (copy_from_user((char *) &sec, optval, len)) {
+                        err = -EFAULT;
+                        break;
+                }
+
+                if (sec.level > BT_SECURITY_HIGH) {
+                        err = -EINVAL;
+                        break;
+                }
+
+                rfcomm_pi(sk)->sec_level = sec.level;
+                break;
+
         case BT_DEFER_SETUP:
                 if (sk->sk_state != BT_BOUND && sk->sk_state != BT_LISTEN) {
                         err = -EINVAL;
@@ -796,6 +827,7 @@ static int rfcomm_sock_getsockopt_old(struct socket *sock, int optname, char __u
         struct sock *l2cap_sk;
         struct rfcomm_conninfo cinfo;
         int len, err = 0;
+        u32 opt;
 
         BT_DBG("sk %p", sk);
 
@@ -806,7 +838,26 @@ static int rfcomm_sock_getsockopt_old(struct socket *sock, int optname, char __u
 
         switch (optname) {
         case RFCOMM_LM:
-                if (put_user(rfcomm_pi(sk)->link_mode, (u32 __user *) optval))
+                switch (rfcomm_pi(sk)->sec_level) {
+                case BT_SECURITY_LOW:
+                        opt = RFCOMM_LM_AUTH;
+                        break;
+                case BT_SECURITY_MEDIUM:
+                        opt = RFCOMM_LM_AUTH | RFCOMM_LM_ENCRYPT;
+                        break;
+                case BT_SECURITY_HIGH:
+                        opt = RFCOMM_LM_AUTH | RFCOMM_LM_ENCRYPT |
+                                                        RFCOMM_LM_SECURE;
+                        break;
+                default:
+                        opt = 0;
+                        break;
+                }
+
+                if (rfcomm_pi(sk)->role_switch)
+                        opt |= RFCOMM_LM_MASTER;
+
+                if (put_user(opt, (u32 __user *) optval))
                         err = -EFAULT;
                 break;
 
@@ -840,6 +891,7 @@ static int rfcomm_sock_getsockopt_old(struct socket *sock, int optname, char __u
 static int rfcomm_sock_getsockopt(struct socket *sock, int level, int optname, char __user *optval, int __user *optlen)
 {
         struct sock *sk = sock->sk;
+        struct bt_security sec;
         int len, err = 0;
 
         BT_DBG("sk %p", sk);
@@ -853,6 +905,15 @@ static int rfcomm_sock_getsockopt(struct socket *sock, int level, int optname, c
         lock_sock(sk);
 
         switch (optname) {
+        case BT_SECURITY:
+                sec.level = rfcomm_pi(sk)->sec_level;
+
+                len = min_t(unsigned int, len, sizeof(sec));
+                if (copy_to_user(optval, (char *) &sec, len))
+                        err = -EFAULT;
+
+                break;
+
         case BT_DEFER_SETUP:
                 if (sk->sk_state != BT_BOUND && sk->sk_state != BT_LISTEN) {
                         err = -EINVAL;