Bluetooth: Add simple SMP pairing negotiation

This implementation only exchanges SMP messages between the Host and the
Remote. No keys are being generated. TK and STK generation will be
provided in further patches.

Signed-off-by: Vinicius Costa Gomes <vinicius.gomes@openbossa.org>
Signed-off-by: Gustavo F. Padovan <padovan@profusion.mobi>

diff --git a/include/net/bluetooth/smp.h b/include/net/bluetooth/smp.h
index 36bdd6e..111853a 100644 (file)
--- a/include/net/bluetooth/smp.h
+++ b/include/net/bluetooth/smp.h
@@ -38,6 +38,23 @@ struct smp_cmd_pairing {
        __u8    resp_key_dist;
 } __packed;
 
+#define SMP_IO_DISPLAY_ONLY    0x00
+#define SMP_IO_DISPLAY_YESNO   0x01
+#define SMP_IO_KEYBOARD_ONLY   0x02
+#define SMP_IO_NO_INPUT_OUTPUT 0x03
+#define SMP_IO_KEYBOARD_DISPLAY        0x04
+
+#define SMP_OOB_NOT_PRESENT    0x00
+#define SMP_OOB_PRESENT                0x01
+
+#define SMP_DIST_ENC_KEY       0x01
+#define SMP_DIST_ID_KEY                0x02
+#define SMP_DIST_SIGN          0x04
+
+#define SMP_AUTH_NONE          0x00
+#define SMP_AUTH_BONDING       0x01
+#define SMP_AUTH_MITM          0x04
+
 #define SMP_CMD_PAIRING_CONFIRM        0x03
 struct smp_cmd_pairing_confirm {
        __u8    confirm_val[16];

diff --git a/net/bluetooth/smp.c b/net/bluetooth/smp.c
index aa0434f..2240e96 100644 (file)
--- a/net/bluetooth/smp.c
+++ b/net/bluetooth/smp.c
@@ -64,6 +64,94 @@ static void smp_send_cmd(struct l2cap_conn *conn, u8 code, u16 len, void *data)
        hci_send_acl(conn->hcon, skb, 0);
 }
 
+static void smp_cmd_pairing_req(struct l2cap_conn *conn, struct sk_buff *skb)
+{
+       struct smp_cmd_pairing *rp = (void *) skb->data;
+
+       BT_DBG("conn %p", conn);
+
+       skb_pull(skb, sizeof(*rp));
+
+       rp->io_capability = 0x00;
+       rp->oob_flag = 0x00;
+       rp->max_key_size = 16;
+       rp->init_key_dist = 0x00;
+       rp->resp_key_dist = 0x00;
+       rp->auth_req &= (SMP_AUTH_BONDING | SMP_AUTH_MITM);
+
+       smp_send_cmd(conn, SMP_CMD_PAIRING_RSP, sizeof(*rp), rp);
+}
+
+static void smp_cmd_pairing_rsp(struct l2cap_conn *conn, struct sk_buff *skb)
+{
+       struct smp_cmd_pairing_confirm cp;
+
+       BT_DBG("conn %p", conn);
+
+       memset(&cp, 0, sizeof(cp));
+
+       smp_send_cmd(conn, SMP_CMD_PAIRING_CONFIRM, sizeof(cp), &cp);
+}
+
+static void smp_cmd_pairing_confirm(struct l2cap_conn *conn,
+                                                       struct sk_buff *skb)
+{
+       BT_DBG("conn %p %s", conn, conn->hcon->out ? "master" : "slave");
+
+       if (conn->hcon->out) {
+               struct smp_cmd_pairing_random random;
+
+               memset(&random, 0, sizeof(random));
+
+               smp_send_cmd(conn, SMP_CMD_PAIRING_RANDOM, sizeof(random),
+                                                               &random);
+       } else {
+               struct smp_cmd_pairing_confirm confirm;
+
+               memset(&confirm, 0, sizeof(confirm));
+
+               smp_send_cmd(conn, SMP_CMD_PAIRING_CONFIRM, sizeof(confirm),
+                                                               &confirm);
+       }
+}
+
+static void smp_cmd_pairing_random(struct l2cap_conn *conn, struct sk_buff *skb)
+{
+       struct smp_cmd_pairing_random cp;
+
+       BT_DBG("conn %p %s", conn, conn->hcon->out ? "master" : "slave");
+
+       skb_pull(skb, sizeof(cp));
+
+       if (conn->hcon->out) {
+               /* FIXME: start encryption */
+       } else {
+               memset(&cp, 0, sizeof(cp));
+
+               smp_send_cmd(conn, SMP_CMD_PAIRING_RANDOM, sizeof(cp), &cp);
+       }
+}
+
+static void smp_cmd_security_req(struct l2cap_conn *conn, struct sk_buff *skb)
+{
+       struct smp_cmd_security_req *rp = (void *) skb->data;
+       struct smp_cmd_pairing cp;
+
+       BT_DBG("conn %p", conn);
+
+       skb_pull(skb, sizeof(*rp));
+       memset(&cp, 0, sizeof(cp));
+
+       cp.io_capability = 0x00;
+       cp.oob_flag = 0x00;
+       cp.max_key_size = 16;
+       cp.init_key_dist = 0x00;
+       cp.resp_key_dist = 0x00;
+       cp.auth_req = rp->auth_req & (SMP_AUTH_BONDING | SMP_AUTH_MITM);
+
+       smp_send_cmd(conn, SMP_CMD_PAIRING_REQ, sizeof(cp), &cp);
+}
+
 int smp_conn_security(struct l2cap_conn *conn, __u8 sec_level)
 {
        __u8 authreq;
@@ -114,24 +202,33 @@ int smp_sig_channel(struct l2cap_conn *conn, struct sk_buff *skb)
 
        switch (code) {
        case SMP_CMD_PAIRING_REQ:
-               reason = SMP_PAIRING_NOTSUPP;
-               smp_send_cmd(conn, SMP_CMD_PAIRING_FAIL, sizeof(reason),
-                                                               &reason);
-               err = -EOPNOTSUPP;
+               smp_cmd_pairing_req(conn, skb);
                break;
 
        case SMP_CMD_PAIRING_FAIL:
                break;
 
        case SMP_CMD_PAIRING_RSP:
+               smp_cmd_pairing_rsp(conn, skb);
+               break;
+
+       case SMP_CMD_SECURITY_REQ:
+               smp_cmd_security_req(conn, skb);
+               break;
+
        case SMP_CMD_PAIRING_CONFIRM:
+               smp_cmd_pairing_confirm(conn, skb);
+               break;
+
        case SMP_CMD_PAIRING_RANDOM:
+               smp_cmd_pairing_random(conn, skb);
+               break;
+
        case SMP_CMD_ENCRYPT_INFO:
        case SMP_CMD_MASTER_IDENT:
        case SMP_CMD_IDENT_INFO:
        case SMP_CMD_IDENT_ADDR_INFO:
        case SMP_CMD_SIGN_INFO:
-       case SMP_CMD_SECURITY_REQ:
        default:
                BT_DBG("Unknown command code 0x%2.2x", code);