xref: /btstack/src/ble/sm.h (revision 5ce1359ee5f0fe594f97c68ec2795ef20f59817f)
1 /*
2  * Copyright (C) 2014 BlueKitchen GmbH
3  *
4  * Redistribution and use in source and binary forms, with or without
5  * modification, are permitted provided that the following conditions
6  * are met:
7  *
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9  *    notice, this list of conditions and the following disclaimer.
10  * 2. Redistributions in binary form must reproduce the above copyright
11  *    notice, this list of conditions and the following disclaimer in the
12  *    documentation and/or other materials provided with the distribution.
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15  *    from this software without specific prior written permission.
16  * 4. Any redistribution, use, or modification is done solely for
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20  * THIS SOFTWARE IS PROVIDED BY BLUEKITCHEN GMBH AND CONTRIBUTORS
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37 
38 /**
39  * @title Security Manager
40  *
41  */
42 
43 #ifndef SM_H
44 #define SM_H
45 
46 #if defined __cplusplus
47 extern "C" {
48 #endif
49 
50 #include <stdint.h>
51 #include "btstack_util.h"
52 #include "btstack_defines.h"
53 #include "hci.h"
54 
55 typedef struct {
56     btstack_linked_item_t  item;
57     bd_addr_t      address;
58     bd_addr_type_t address_type;
59 } sm_lookup_entry_t;
60 
61 /* API_START */
62 
63 /**
64  * @brief Initializes the Security Manager, connects to L2CAP
65  */
66 void sm_init(void);
67 
68 /**
69  * @brief Set secret ER key for key generation as described in Core V4.0, Vol 3, Part G, 5.2.2
70  * @note If not set and btstack_tlv is configured, ER key is generated and stored in TLV by SM
71  * @param er
72  */
73 void sm_set_er(sm_key_t er);
74 
75 /**
76  * @brief Set secret IR key for key generation as described in Core V4.0, Vol 3, Part G, 5.2.2
77  * @note If not set and btstack_tlv is configured, IR key is generated and stored in TLV by SM
78  */
79 void sm_set_ir(sm_key_t ir);
80 
81 /**
82  *
83  * @brief Registers OOB Data Callback. The callback should set the oob_data and return 1 if OOB data is availble
84  * @param get_oob_data_callback
85  */
86 void sm_register_oob_data_callback( int (*get_oob_data_callback)(uint8_t address_type, bd_addr_t addr, uint8_t * oob_data));
87 
88 /**
89  * @brief Add event packet handler.
90  */
91 void sm_add_event_handler(btstack_packet_callback_registration_t * callback_handler);
92 
93 /**
94  * @brief Limit the STK generation methods. Bonding is stopped if the resulting one isn't in the list
95  * @param OR combination of SM_STK_GENERATION_METHOD_
96  */
97 void sm_set_accepted_stk_generation_methods(uint8_t accepted_stk_generation_methods);
98 
99 /**
100  * @brief Set the accepted encryption key size range. Bonding is stopped if the result isn't within the range
101  * @param min_size (default 7)
102  * @param max_size (default 16)
103  */
104 void sm_set_encryption_key_size_range(uint8_t min_size, uint8_t max_size);
105 
106 /**
107  * @brief Sets the requested authentication requirements, bonding yes/no, MITM yes/no, SC yes/no, keypress yes/no
108  * @param OR combination of SM_AUTHREQ_ flags
109  */
110 void sm_set_authentication_requirements(uint8_t auth_req);
111 
112 /**
113  * @brief Sets the available IO Capabilities
114  * @param IO_CAPABILITY_
115  */
116 void sm_set_io_capabilities(io_capability_t io_capability);
117 
118 /**
119  * @brief Enable/disable Secure Connections Mode only
120  * @param enable secure connections only mode
121  */
122 void sm_set_secure_connections_only_mode(bool enable);
123 
124 /**
125  * @brief Let Peripheral request an encrypted connection right after connecting
126  * @note Not used normally. Bonding is triggered by access to protected attributes in ATT Server
127  */
128 void sm_set_request_security(int enable);
129 
130 /**
131  * @brief Trigger Security Request
132  * @deprecated please use sm_request_pairing instead
133  */
134 void sm_send_security_request(hci_con_handle_t con_handle);
135 
136 /**
137  * @brief Decline bonding triggered by event before
138  * @param con_handle
139  */
140 void sm_bonding_decline(hci_con_handle_t con_handle);
141 
142 /**
143  * @brief Confirm Just Works bonding
144  * @param con_handle
145  */
146 void sm_just_works_confirm(hci_con_handle_t con_handle);
147 
148 /**
149  * @brief Confirm value from SM_EVENT_NUMERIC_COMPARISON_REQUEST for Numeric Comparison bonding
150  * @param con_handle
151  */
152 void sm_numeric_comparison_confirm(hci_con_handle_t con_handle);
153 
154 /**
155  * @brief Reports passkey input by user
156  * @param con_handle
157  * @param passkey in [0..999999]
158  */
159 void sm_passkey_input(hci_con_handle_t con_handle, uint32_t passkey);
160 
161 /**
162  * @brief Send keypress notification for keyboard only devices
163  * @param con_handle
164  * @param action see SM_KEYPRESS_* in bluetooth.h
165  */
166 void sm_keypress_notification(hci_con_handle_t con_handle, uint8_t action);
167 
168 /**
169  * @brief Used by att_server.c and gatt_client.c to request user authentication
170  * @param con_handle
171  */
172 void sm_request_pairing(hci_con_handle_t con_handle);
173 
174 /**
175  * @brief Report user authorization decline.
176  * @param con_handle
177  */
178 void sm_authorization_decline(hci_con_handle_t con_handle);
179 
180 /**
181  * @brief Report user authorization grant.
182  * @param con_handle
183  */
184 void sm_authorization_grant(hci_con_handle_t con_handle);
185 
186 /**
187  * @brief Support for signed writes, used by att_server.
188  * @returns ready
189  */
190 int sm_cmac_ready(void);
191 
192 /**
193  * @brief Support for signed writes, used by att_server.
194  * @note Message is in little endian to allows passing in ATT PDU without flipping.
195  * @note signing data: [opcode, attribute_handle, message, sign_counter]
196  * @note calculated hash in done_callback is big endian and has 16 byte.
197  * @param key
198  * @param opcde
199  * @param attribute_handle
200  * @param message_len
201  * @param message
202  * @param sign_counter
203  */
204 void sm_cmac_signed_write_start(const sm_key_t key, uint8_t opcode, uint16_t attribute_handle, uint16_t message_len, const uint8_t * message, uint32_t sign_counter, void (*done_callback)(uint8_t * hash));
205 
206 /*
207  * @brief Match address against bonded devices
208  * @return 0 if successfully added to lookup queue
209  * @note Triggers SM_IDENTITY_RESOLVING_* events
210  */
211 int sm_address_resolution_lookup(uint8_t addr_type, bd_addr_t addr);
212 
213 /**
214  * @brief Get Identity Resolving state
215  * @param con_handle
216  * @return irk_lookup_state_t
217  * @note returns IRK_LOOKUP_IDLE if connection does not exist
218  */
219 irk_lookup_state_t sm_identity_resolving_state(hci_con_handle_t con_handle);
220 
221 /**
222  * @brief Identify device in LE Device DB.
223  * @param handle
224  * @return index from le_device_db or -1 if not found/identified
225  */
226 int sm_le_device_index(hci_con_handle_t con_handle );
227 
228 /**
229  * @brief Use fixec passkey for Legacy and SC instead of generating a random number
230  * @note Can be used to improve security over Just Works if no keyboard or displary are present and
231  *       individual random passkey can be printed on the device during production
232  * @param passkey
233  */
234 void sm_use_fixed_passkey_in_display_role(uint32_t passkey);
235 
236 /**
237  * @brief Allow connection re-encryption in Peripheral (Responder) role for LE Legacy Pairing
238  *       without entry for Central device stored in LE Device DB
239  * @note BTstack in Peripheral Role (Responder) supports LE Legacy Pairing without a persistent LE Device DB as
240  *       the LTK is reconstructed from a local secret IRK and EDIV + Random stored on Central (Initiator) device
241  *       On the downside, it's not really possible to delete a pairing if this is enabled.
242  * @param allow encryption using reconstructed LTK without stored entry (Default: 1)
243  */
244 void sm_allow_ltk_reconstruction_without_le_device_db_entry(int allow);
245 
246 /**
247  * @brief Generate OOB data for LE Secure Connections
248  * @note This generates a 128 bit random number ra and then calculates Ca = f4(PKa, PKa, ra, 0)
249  *       New OOB data should be generated for each pairing. Ra is used for subsequent OOB pairings
250  * @param callback
251  * @returns status
252  */
253 uint8_t sm_generate_sc_oob_data(void (*callback)(const uint8_t * confirm_value, const uint8_t * random_value));
254 
255 /**
256  *
257  * @brief Registers OOB Data Callback for LE Secure Conections. The callback should set all arguments and return 1 if OOB data is availble
258  * @note the oob_sc_local_random usually is the random_value returend by sm_generate_sc_oob_data
259  * @param get_oob_data_callback
260  */
261 void sm_register_sc_oob_data_callback( int (*get_sc_oob_data_callback)(uint8_t address_type, bd_addr_t addr, uint8_t * oob_sc_peer_confirm, uint8_t * oob_sc_peer_random));
262 
263 /* API_END */
264 
265 /**
266  * @brief De-Init SM
267  */
268 void sm_deinit(void);
269 
270 // PTS testing
271 void sm_test_set_irk(sm_key_t irk);
272 void sm_test_use_fixed_local_csrk(void);
273 
274 #ifdef ENABLE_TESTING_SUPPORT
275 void sm_test_set_pairing_failure(int reason);
276 #endif
277 
278 #if defined __cplusplus
279 }
280 #endif
281 
282 #endif // SM_H
283