From f8ee30711d382a32d09f62fdcf31e17b8873cde8 Mon Sep 17 00:00:00 2001
From: Matthias Ringwald <matthias@ringwald.ch>
Date: Mon, 22 Oct 2018 14:05:59 +0200
Subject: [PATCH] hci/gap: support snif mode

---
 CHANGELOG.md |  1 +
 src/gap.h    | 16 ++++++++++++++++
 src/hci.c    | 41 +++++++++++++++++++++++++++++++++++++++++
 src/hci.h    | 11 ++++++++++-
 4 files changed, 68 insertions(+), 1 deletion(-)

diff --git a/CHANGELOG.md b/CHANGELOG.md
index 8c4d5a44f..d6e728587 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -8,6 +8,7 @@ and this project adheres to [Semantic Versioning](http://semver.org/spec/v2.0.0.
 
 ### Added
 - SDP Server: queue incoming connections when already connected instead of rejecting them
+- GAP: Support enter/exit sniff mode via gap_sniff_mode_enter/exit. gap_set_default_link_policy_settings is needed to enable sniff mode in general.
 
 ### Fixed
 - HCI: fix bug in gap_inquiry_stop that triggered additional GAP_EVENT_INQUIRY_COMPLETE instead of stopping the inquiry
diff --git a/src/gap.h b/src/gap.h
index f858463af..eefbcbc20 100644
--- a/src/gap.h
+++ b/src/gap.h
@@ -553,7 +553,23 @@ int gap_ssp_confirmation_response(bd_addr_t addr);
  */
 int gap_ssp_confirmation_negative(bd_addr_t addr);
 
+/**
+ * @brief Enter Sniff mode
+ * @param con_handle
+ * @param sniff_min_interval range: 0x0002 to 0xFFFE; only even values are valid, Time = N * 0.625 ms
+ * @param sniff_max_interval range: 0x0002 to 0xFFFE; only even values are valid, Time = N * 0.625 ms
+ * @param sniff_attempt Number of Baseband receive slots for sniff attempt.
+ * @param sniff_timeout Number of Baseband receive slots for sniff timeout.
+ @ @return 0 if ok
+ */
+uint8_t gap_sniff_mode_enter(hci_con_handle_t con_handle, uint16_t sniff_min_interval, uint16_t sniff_max_interval, uint16_t sniff_attempt, uint16_t sniff_timeout);
 
+/**
+ * @brief Exit Sniff mode
+ * @param con_handle
+ @ @return 0 if ok
+ */
+uint8_t gap_sniff_mode_exit(hci_con_handle_t con_handle);
 
 // LE
 
diff --git a/src/hci.c b/src/hci.c
index d1f254226..975f930ca 100644
--- a/src/hci.c
+++ b/src/hci.c
@@ -3463,6 +3463,21 @@ static void hci_run(void){
             return;
         }
 
+        uint16_t sniff_min_interval;
+        switch (connection->sniff_min_interval){
+            case 0:
+                break;
+            case 0xffff:
+                connection->sniff_min_interval = 0;
+                hci_send_cmd(&hci_exit_sniff_mode, connection->con_handle);
+                return;
+            default:
+                sniff_min_interval = connection->sniff_min_interval;
+                connection->sniff_min_interval = 0;
+                hci_send_cmd(&hci_sniff_mode, connection->con_handle, connection->sniff_max_interval, sniff_min_interval, connection->sniff_attempt, connection->sniff_timeout);
+                break;
+        }
+
 #ifdef ENABLE_BLE
         switch (connection->le_con_parameter_update_state){
             // response to L2CAP CON PARAMETER UPDATE REQUEST
@@ -4836,3 +4851,29 @@ authorization_state_t gap_authorization_state(hci_con_handle_t con_handle){
     return sm_conn->sm_connection_authorization_state;
 }
 #endif
+
+#ifdef ENABLE_CLASSIC
+uint8_t gap_sniff_mode_enter(hci_con_handle_t con_handle, uint16_t sniff_min_interval, uint16_t sniff_max_interval, uint16_t sniff_attempt, uint16_t sniff_timeout){
+    hci_connection_t * conn = hci_connection_for_handle(con_handle);
+    if (!conn) return GAP_CONNECTION_INVALID;
+    conn->sniff_min_interval = sniff_min_interval;
+    conn->sniff_max_interval = sniff_max_interval;
+    conn->sniff_attempt = sniff_attempt;
+    conn->sniff_timeout = sniff_timeout;
+    hci_run();
+    return 0;
+}
+
+/**
+ * @brief Exit Sniff mode
+ * @param con_handle
+ @ @return 0 if ok
+ */
+uint8_t gap_sniff_mode_exit(hci_con_handle_t con_handle){
+    hci_connection_t * conn = hci_connection_for_handle(con_handle);
+    if (!conn) return GAP_CONNECTION_INVALID;
+    conn->sniff_min_interval = 0xffff;
+    hci_run();
+    return 0;
+}
+#endif
diff --git a/src/hci.h b/src/hci.h
index fc0a5966c..583f9aebc 100644
--- a/src/hci.h
+++ b/src/hci.h
@@ -475,6 +475,7 @@ typedef struct {
     // bonding
     uint16_t bonding_flags;
     uint8_t  bonding_status;
+
     // requested security level
     gap_security_level_t requested_security_level;
 
@@ -484,9 +485,17 @@ typedef struct {
     // remote supported features
     uint8_t remote_supported_feature_eSCO;
 
-    // conenction mode, default ACL_CONNECTION_MODE_ACTIVE
+#ifdef ENABLE_CLASSIC
+    // connection mode, default ACL_CONNECTION_MODE_ACTIVE
     uint8_t connection_mode;
 
+    // enter/exit sniff mode requests
+    uint16_t sniff_min_interval;    // 0: idle, 0xffff exit sniff, else enter sniff
+    uint16_t sniff_max_interval;
+    uint16_t sniff_attempt;
+    uint16_t sniff_timeout;
+#endif
+
     // errands
     uint32_t authentication_flags;