1 /*
2  * Copyright 2022 NXP
3  *
4  * Licensed under the Apache License, Version 2.0 (the "License");
5  * you may not use this file except in compliance with the License.
6  * You may obtain a copy of the License at
7  *
8  *      http://www.apache.org/licenses/LICENSE-2.0
9  *
10  * Unless required by applicable law or agreed to in writing, software
11  * distributed under the License is distributed on an "AS IS" BASIS,
12  * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
13  * See the License for the specific language governing permissions and
14  * limitations under the License.
15  */
16 
17 #include "NfcDta.h"
18 
19 #include <android-base/logging.h>
20 #include <android-base/stringprintf.h>
21 #include <cutils/properties.h>
22 
23 #include "SyncEvent.h"
24 
25 using android::base::StringPrintf;
26 
27 namespace android {
28 extern SyncEvent gNfaSetConfigEvent;
29 extern SyncEvent gNfaGetConfigEvent;
30 extern uint16_t gCurrentConfigLen;
31 extern uint8_t gConfig[256];
32 }  // namespace android
33 
34 using namespace android;
35 
36 /*******************************************************************************
37 **
38 ** Function:        NfcDta
39 **
40 ** Description:     Initialize member variables.
41 **
42 ** Returns:         None
43 **
44 *******************************************************************************/
NfcDta()45 NfcDta::NfcDta() {
46   mDefaultTlv.clear();
47   mUpdatedParamIds.clear();
48 }
49 
50 /*******************************************************************************
51 **
52 ** Function:        getInstance
53 **
54 ** Description:     Get a reference to the singleton NfcDta object.
55 **
56 ** Returns:         Reference to NfcDta object.
57 **
58 *******************************************************************************/
getInstance()59 NfcDta& NfcDta::getInstance() {
60   static NfcDta dtaInstance;
61   return dtaInstance;
62 }
63 
64 /*******************************************************************************
65 **
66 ** Function:        parseConfigParams
67 **
68 ** Description:     Parse config TLV from the String
69 **
70 ** Returns:         uint8_t vector
71 **
72 *******************************************************************************/
parseConfigParams(std::string configParams)73 std::vector<uint8_t> NfcDta::parseConfigParams(std::string configParams) {
74   std::vector<uint8_t> configTlv;
75   uint16_t index = 0;
76   while (index < configParams.size()) {
77     // Parsing tag
78     configTlv.push_back(
79         (uint8_t)strtol(configParams.substr(index, 2).c_str(), NULL, 16));
80     // Parsing length
81     index += 2;
82     uint16_t len =
83         (uint8_t)strtol(configParams.substr(index, 2).c_str(), NULL, 16);
84     configTlv.push_back(len);
85     // Parsing value
86     for (uint16_t i = 0; i < len; i++) {
87       index += 2;
88       configTlv.push_back(
89           (uint8_t)strtol(configParams.substr(index, 2).c_str(), NULL, 16));
90     }
91     index += 2;
92     if (configParams[index] == '_') {
93       index++;
94     }
95   }
96   return configTlv;
97 }
98 
99 /*******************************************************************************
100 **
101 ** Function:        getNonupdatedConfigParamIds
102 **
103 ** Description:     Get config parameter Ids whose values are not modified.
104 **
105 ** Returns:         config Parameter ids vector.
106 **
107 *******************************************************************************/
getNonupdatedConfigParamIds(std::vector<uint8_t> configTlv)108 std::vector<uint8_t> NfcDta::getNonupdatedConfigParamIds(
109     std::vector<uint8_t> configTlv) {
110   std::vector<uint8_t> paramIds;
111   uint16_t index = 0;
112   uint8_t len = 0;
113   uint8_t paramId = 0;
114   while (index < configTlv.size()) {
115     paramId = configTlv[index++];
116     std::unordered_set<uint8_t>::const_iterator found =
117         mUpdatedParamIds.find(paramId);
118     if (found == mUpdatedParamIds.end()) {
119       mUpdatedParamIds.insert(paramId);
120       paramIds.push_back(paramId);
121     }
122     len = configTlv[index++];
123     index += len;
124   }
125   return paramIds;
126 }
127 
128 /*******************************************************************************
129 **
130 ** Function:        getConfigParamValues
131 **
132 ** Description:     Read the current config parameter values.
133 **
134 ** Returns:         None.
135 **
136 *******************************************************************************/
getConfigParamValues(std::vector<uint8_t> paramIds)137 tNFA_STATUS NfcDta::getConfigParamValues(std::vector<uint8_t> paramIds) {
138   tNFA_STATUS status = NFA_STATUS_OK;
139   if (!paramIds.empty()) {
140     SyncEventGuard guard(gNfaGetConfigEvent);
141     status = NFA_GetConfig(paramIds.size(), paramIds.data());
142     if (status == NFA_STATUS_OK) {
143       gNfaGetConfigEvent.wait();
144       // gCurrentConfigLen contains number of bytes without NCI header length.
145       // i.e., status(one byte) + config tag count(one byte) + NCI config
146       // Tag(one byte) + length(one byte) + value(bytes). So valid getConfig
147       // response length should be greater than 4.
148       if (gCurrentConfigLen > 4) {
149         // Config tlv length = gCurrentConfigLen - status byte - tag count byte
150         uint16_t len = gCurrentConfigLen - 2;
151         // First Config TLV starts from index 1 of gConfig
152         uint16_t index = 1;
153         LOG(DEBUG) << StringPrintf("%s: default_config len: %d", __func__, len);
154         while (index <= len) {
155           mDefaultTlv.push_back(gConfig[index++]);
156         }
157       } else {
158         LOG(DEBUG) << StringPrintf("%s: getConfig failed len: %d", __func__,
159                                    gCurrentConfigLen);
160         status = NFA_STATUS_FAILED;
161       }
162     } else {
163       LOG(DEBUG) << StringPrintf("%s: getConfig failed", __func__);
164     }
165   }
166   return status;
167 }
168 
169 /*******************************************************************************
170 **
171 ** Function:        setConfigParams
172 **
173 ** Description:     Set config param with new value.
174 **
175 ** Returns:         NFA_STATUS_OK if success
176 **
177 *******************************************************************************/
setConfigParams(std::vector<uint8_t> configTlv)178 tNFA_STATUS NfcDta::setConfigParams(std::vector<uint8_t> configTlv) {
179   tNFA_STATUS status = NFA_STATUS_FAILED;
180   uint16_t index = 0;
181   uint8_t paramId = 0;
182   uint8_t len = 0;
183   while (index < configTlv.size()) {
184     paramId = configTlv[index++];
185     len = configTlv[index++];
186     LOG(DEBUG) << StringPrintf("%s: Param Id: %02X, Length: %02X", __func__,
187                                paramId, len);
188     SyncEventGuard guard(gNfaSetConfigEvent);
189     status = NFA_SetConfig(paramId, len, &configTlv[index]);
190     if (status == NFA_STATUS_OK) {
191       gNfaSetConfigEvent.wait();
192     } else {
193       LOG(DEBUG) << StringPrintf("%s: setConfig failed", __func__);
194       break;
195     }
196     index += len;
197   }
198   return status;
199 }
200 
201 /*******************************************************************************
202 **
203 ** Function:        setNfccConfigParams
204 **
205 ** Description:     Set NCI config params from nfc.configTLV System Property.
206 **
207 ** Returns:         None.
208 **
209 *******************************************************************************/
setNfccConfigParams()210 void NfcDta::setNfccConfigParams() {
211   char sysPropTlvs[256];
212   int len = 0;
213   len = property_get("nfc.dta.configTLV", sysPropTlvs, "");
214   std::string configTlvs(sysPropTlvs);
215   LOG(DEBUG) << StringPrintf("%s: SysProperty nfc.configTLV: %s", __func__,
216                              configTlvs.c_str());
217   if (len <= 0 || (configTlvs.empty() && mDefaultTlv.empty())) {
218     LOG(DEBUG) << StringPrintf("%s: Config TLVs not available", __func__);
219     return;
220   }
221   tNFA_STATUS status = NFA_STATUS_FAILED;
222   if (configTlvs.empty() && !mDefaultTlv.empty()) {
223     status = setConfigParams(mDefaultTlv);
224     if (status == NFA_STATUS_OK) {
225       mDefaultTlv.clear();
226       mUpdatedParamIds.clear();
227       LOG(DEBUG) << StringPrintf("%s: Restored default config params",
228                                  __func__);
229     }
230     return;
231   }
232 
233   std::vector<uint8_t> tlv = parseConfigParams(configTlvs);
234   std::vector<uint8_t> paramIds = getNonupdatedConfigParamIds(tlv);
235   status = getConfigParamValues(paramIds);
236   if (status == NFA_STATUS_OK) {
237     setConfigParams(tlv);
238   }
239   LOG(DEBUG) << StringPrintf("%s: Exit", __func__);
240 }
241