From: Luiz Augusto von Dentz <luiz.von.dentz@xxxxxxxxx>
Enhanced Credit Based Flow Control Mode is used for L2CAP
connection-oriented channels on LE and BR/EDR with flow control using
a credit-based scheme for L2CAP data.
---
monitor/bt.h | 30 ++++++++++
monitor/l2cap.c | 153 ++++++++++++++++++++++++++++++++++++++++++++++++
2 files changed, 183 insertions(+)
diff --git a/monitor/bt.h b/monitor/bt.h
index c2e6964ff..d989f5b94 100644
--- a/monitor/bt.h
+++ b/monitor/bt.h
@@ -3712,6 +3712,36 @@ struct bt_l2cap_pdu_le_flowctl_creds {
uint16_t credits;
} __attribute__ ((packed));
+#define BT_L2CAP_PDU_ECRED_CONN_REQ 0x17
+struct bt_l2cap_pdu_ecred_conn_req {
+ uint16_t psm;
+ uint16_t mtu;
+ uint16_t mps;
+ uint16_t credits;
+ uint16_t scid[0];
+} __attribute__ ((packed));
+
+#define BT_L2CAP_PDU_ECRED_CONN_RSP 0x18
+struct bt_l2cap_pdu_ecred_conn_rsp {
+ uint16_t mtu;
+ uint16_t mps;
+ uint16_t credits;
+ uint16_t result;
+ uint16_t dcid[0];
+} __attribute__ ((packed));
+
+#define BT_L2CAP_PDU_ECRED_RECONF_REQ 0x19
+struct bt_l2cap_pdu_ecred_reconf_req {
+ uint16_t mtu;
+ uint16_t mps;
+ uint16_t scid[0];
+} __attribute__ ((packed));
+
+#define BT_L2CAP_PDU_ECRED_RECONF_RSP 0x1a
+struct bt_l2cap_pdu_ecred_reconf_rsp {
+ uint16_t result;
+} __attribute__ ((packed));
+
struct bt_l2cap_hdr_connless {
uint16_t psm;
} __attribute__ ((packed));
diff --git a/monitor/l2cap.c b/monitor/l2cap.c
index d4feca451..3b2b25f24 100644
--- a/monitor/l2cap.c
+++ b/monitor/l2cap.c
@@ -54,6 +54,7 @@
#define L2CAP_MODE_ERTM 0x03
#define L2CAP_MODE_STREAMING 0x04
#define L2CAP_MODE_LE_FLOWCTL 0x80
+#define L2CAP_MODE_ECRED 0x81
/* L2CAP Control Field bit masks */
#define L2CAP_CTRL_SAR_MASK 0xC000
@@ -121,6 +122,9 @@ static void assign_scid(const struct l2cap_frame *frame, uint16_t scid,
int i, n = -1;
uint8_t seq_num = 1;
+ if (!scid)
+ return;
+
for (i = 0; i < MAX_CHAN; i++) {
if (n < 0 && chan_list[i].handle == 0x0000) {
n = i;
@@ -417,6 +421,8 @@ static char *mode2str(uint8_t mode)
return "Streaming";
case L2CAP_MODE_LE_FLOWCTL:
return "LE Flow Control";
+ case L2CAP_MODE_ECRED:
+ return "Enhanced Credit";
default:
return "Unknown";
}
@@ -1333,6 +1339,132 @@ static void sig_le_flowctl_creds(const struct l2cap_frame *frame)
print_field("Credits: %u", le16_to_cpu(pdu->credits));
}
+static void sig_ecred_conn_req(const struct l2cap_frame *frame)
+{
+ const struct bt_l2cap_pdu_ecred_conn_req *pdu = frame->data;
+ uint16_t scid;
+
+ l2cap_frame_pull((void *)frame, frame, sizeof(pdu));
+
+ print_psm(pdu->psm);
+ print_field("MTU: %u", le16_to_cpu(pdu->mtu));
+ print_field("MPS: %u", le16_to_cpu(pdu->mps));
+ print_field("Credits: %u", le16_to_cpu(pdu->credits));
+
+ while (l2cap_frame_get_le16((void *)frame, &scid)) {
+ print_cid("Source", scid);
+ assign_scid(frame, scid, le16_to_cpu(pdu->psm),
+ L2CAP_MODE_ECRED, 0);
+ }
+}
+
+static void print_ecred_conn_result(uint16_t result)
+{
+ const char *str;
+
+ switch (le16_to_cpu(result)) {
+ case 0x0000:
+ str = "Connection successful";
+ break;
+ case 0x0002:
+ str = "Connection refused - PSM not supported";
+ break;
+ case 0x0004:
+ str = "Some connections refused – not enough resources "
+ "available";
+ break;
+ case 0x0005:
+ str = "All Connections refused - insufficient authentication";
+ break;
+ case 0x0006:
+ str = "All Connections refused - insufficient authorization";
+ break;
+ case 0x0007:
+ str = "All Connection refused - insufficient encryption key "
+ "size";
+ break;
+ case 0x0008:
+ str = "All Connections refused - insufficient encryption";
+ break;
+ case 0x0009:
+ str = "Some Connections refused - Invalid Source CID";
+ break;
+ case 0x000a:
+ str = "Some Connections refused - Source CID already allocated";
+ break;
+ case 0x000b:
+ str = "All Connections refused - unacceptable parameters";
+ break;
+ default:
+ str = "Reserved";
+ break;
+ }
+
+ print_field("Result: %s (0x%4.4x)", str, le16_to_cpu(result));
+}
+
+static void sig_ecred_conn_rsp(const struct l2cap_frame *frame)
+{
+ const struct bt_l2cap_pdu_ecred_conn_rsp *pdu = frame->data;
+ uint16_t dcid;
+
+ l2cap_frame_pull((void *)frame, frame, sizeof(pdu));
+
+ print_field("MTU: %u", le16_to_cpu(pdu->mtu));
+ print_field("MPS: %u", le16_to_cpu(pdu->mps));
+ print_field("Credits: %u", le16_to_cpu(pdu->credits));
+ print_ecred_conn_result(pdu->result);
+
+ while (l2cap_frame_get_le16((void *)frame, &dcid)) {
+ print_cid("Destination", dcid);
+ assign_dcid(frame, dcid, 0);
+ }
+}
+
+static void sig_ecred_reconf_req(const struct l2cap_frame *frame)
+{
+ const struct bt_l2cap_pdu_ecred_reconf_req *pdu = frame->data;
+ uint16_t scid;
+
+ l2cap_frame_pull((void *)frame, frame, sizeof(pdu));
+
+ print_field("MTU: %u", le16_to_cpu(pdu->mtu));
+ print_field("MPS: %u", le16_to_cpu(pdu->mps));
+
+ while (l2cap_frame_get_le16((void *)frame, &scid))
+ print_cid("Source", scid);
+}
+
+static void print_ecred_reconf_result(uint16_t result)
+{
+ const char *str;
+
+ switch (le16_to_cpu(result)) {
+ case 0x0000:
+ str = "Reconfiguration successful";
+ break;
+ case 0x0001:
+ str = "Reconfiguration failed - reduction in size of MTU not "
+ "allowed";
+ break;
+ case 0x0002:
+ str = "Reconfiguration failed - reduction in size of MPS not "
+ "allowed for more than one channel at a time";
+ break;
+ default:
+ str = "Reserved";
+ }
+
+ print_field("Result: %s (0x%4.4x)", str, le16_to_cpu(result));
+}
+
+static void sig_ecred_reconf_rsp(const struct l2cap_frame *frame)
+{
+ const struct bt_l2cap_pdu_ecred_reconf_rsp *pdu = frame->data;
+
+ print_ecred_reconf_result(pdu->result);
+}
+
struct sig_opcode_data {
uint8_t opcode;
const char *str;
@@ -1341,6 +1473,24 @@ struct sig_opcode_data {
bool fixed;
};
+#define SIG_ECRED \
+ { BT_L2CAP_PDU_ECRED_CONN_REQ, \
+ "Enhanced Credit Connection Request", \
+ sig_ecred_conn_req, sizeof(struct bt_l2cap_pdu_ecred_conn_req), \
+ false }, \
+ { BT_L2CAP_PDU_ECRED_CONN_RSP, \
+ "Enhanced Credit Connection Response", \
+ sig_ecred_conn_rsp, sizeof(struct bt_l2cap_pdu_ecred_conn_rsp), \
+ false }, \
+ { BT_L2CAP_PDU_ECRED_RECONF_REQ, \
+ "Enhanced Credit Reconfigure Request", \
+ sig_ecred_reconf_req, sizeof(struct bt_l2cap_pdu_ecred_reconf_req), \
+ false }, \
+ { BT_L2CAP_PDU_ECRED_RECONF_RSP, \
+ "Enhanced Credit Reconfigure Respond", \
+ sig_ecred_reconf_rsp, sizeof(struct bt_l2cap_pdu_ecred_reconf_rsp), \
+ true },
+
static const struct sig_opcode_data bredr_sig_opcode_table[] = {
{ 0x01, "Command Reject",
sig_cmd_reject, 2, false },
@@ -1376,6 +1526,7 @@ static const struct sig_opcode_data bredr_sig_opcode_table[] = {
sig_move_chan_cfm, 4, true },
{ 0x11, "Move Channel Confirmation Response",
sig_move_chan_cfm_rsp, 2, true },
+ SIG_ECRED
{ },
};
@@ -1396,6 +1547,7 @@ static const struct sig_opcode_data le_sig_opcode_table[] = {
sig_le_conn_rsp, 10, true },
{ 0x16, "LE Flow Control Credit",
sig_le_flowctl_creds, 4, true },
+ SIG_ECRED
{ },
};
@@ -3066,6 +3218,7 @@ void l2cap_frame(uint16_t index, bool in, uint16_t handle, uint16_t cid,
switch (frame.mode) {
case L2CAP_MODE_LE_FLOWCTL:
+ case L2CAP_MODE_ECRED:
chan = get_chan(&frame);
if (!chan->sdu) {
if (!l2cap_frame_get_le16(&frame, &chan->sdu))
--
2.21.0
