From 6464f35f3771f69cd8d107fff166dc29ab392f97 Mon Sep 17 00:00:00 2001 From: Marcel Holtmann Date: Sat, 20 Oct 2007 13:39:51 +0200 Subject: [PATCH] [Bluetooth] Fall back to L2CAP in basic mode In case the remote entity tries to negogiate retransmission or flow control mode, reject it and fall back to basic mode. Signed-off-by: Marcel Holtmann --- include/net/bluetooth/l2cap.h | 13 +++++++++++++ net/bluetooth/l2cap.c | 32 ++++++++++++++++++++++++-------- 2 files changed, 37 insertions(+), 8 deletions(-) diff --git a/include/net/bluetooth/l2cap.h b/include/net/bluetooth/l2cap.h index e1ea64085c4f..73e115bc12dd 100644 --- a/include/net/bluetooth/l2cap.h +++ b/include/net/bluetooth/l2cap.h @@ -149,6 +149,19 @@ struct l2cap_conf_opt { #define L2CAP_CONF_MAX_SIZE 22 +struct l2cap_conf_rfc { + __u8 mode; + __u8 txwin_size; + __u8 max_transmit; + __le16 retrans_timeout; + __le16 monitor_timeout; + __le16 max_pdu_size; +} __attribute__ ((packed)); + +#define L2CAP_MODE_BASIC 0x00 +#define L2CAP_MODE_RETRANS 0x01 +#define L2CAP_MODE_FLOWCTL 0x02 + struct l2cap_disconn_req { __le16 dcid; __le16 scid; diff --git a/net/bluetooth/l2cap.c b/net/bluetooth/l2cap.c index 733c95dbd07e..6fbbae78b304 100644 --- a/net/bluetooth/l2cap.c +++ b/net/bluetooth/l2cap.c @@ -1048,7 +1048,7 @@ static int l2cap_sock_setsockopt(struct socket *sock, int level, int optname, ch opts.imtu = l2cap_pi(sk)->imtu; opts.omtu = l2cap_pi(sk)->omtu; opts.flush_to = l2cap_pi(sk)->flush_to; - opts.mode = 0x00; + opts.mode = L2CAP_MODE_BASIC; len = min_t(unsigned int, sizeof(opts), optlen); if (copy_from_user((char *) &opts, optval, len)) { @@ -1097,7 +1097,7 @@ static int l2cap_sock_getsockopt(struct socket *sock, int level, int optname, ch opts.imtu = l2cap_pi(sk)->imtu; opts.omtu = l2cap_pi(sk)->omtu; opts.flush_to = l2cap_pi(sk)->flush_to; - opts.mode = 0x00; + opts.mode = L2CAP_MODE_BASIC; len = min_t(unsigned int, len, sizeof(opts)); if (copy_to_user(optval, (char *) &opts, len)) @@ -1376,6 +1376,7 @@ static int l2cap_parse_conf_req(struct sock *sk, void *data) int len = pi->conf_len; int type, hint, olen; unsigned long val; + struct l2cap_conf_rfc rfc = { .mode = L2CAP_MODE_BASIC }; u16 mtu = L2CAP_DEFAULT_MTU; u16 result = L2CAP_CONF_SUCCESS; @@ -1399,6 +1400,11 @@ static int l2cap_parse_conf_req(struct sock *sk, void *data) case L2CAP_CONF_QOS: break; + case L2CAP_CONF_RFC: + if (olen == sizeof(rfc)) + memcpy(&rfc, (void *) val, olen); + break; + default: if (hint) break; @@ -1413,14 +1419,24 @@ static int l2cap_parse_conf_req(struct sock *sk, void *data) /* Configure output options and let the other side know * which ones we don't like. */ - if (mtu < pi->omtu) + if (rfc.mode == L2CAP_MODE_BASIC) { + if (mtu < pi->omtu) + result = L2CAP_CONF_UNACCEPT; + else { + pi->omtu = mtu; + pi->conf_state |= L2CAP_CONF_OUTPUT_DONE; + } + + l2cap_add_conf_opt(&ptr, L2CAP_CONF_MTU, 2, pi->omtu); + } else { result = L2CAP_CONF_UNACCEPT; - else { - pi->omtu = mtu; - pi->conf_state |= L2CAP_CONF_OUTPUT_DONE; - } - l2cap_add_conf_opt(&ptr, L2CAP_CONF_MTU, 2, pi->omtu); + memset(&rfc, 0, sizeof(rfc)); + rfc.mode = L2CAP_MODE_BASIC; + + l2cap_add_conf_opt(&ptr, L2CAP_CONF_RFC, + sizeof(rfc), (unsigned long) &rfc); + } } rsp->scid = cpu_to_le16(pi->dcid); -- 2.30.2