1# SE Access Development 2 3## Introduction 4An electronic device may have one or more secure elements (SEs), such as the embedded SE (eSE) and SIM card. A SIM card that functions as an SE must have the NFC feature. 5 6## When to Use 7An application may need to write data to an SE to emulate an NFC card on the device. The NFC card data may be stored on an eSE or a SIM card. Generally, SEs are preset with rules for access control. An application must have related permissions and can access an SE only after a successful permission verification. 8 9## Available APIs 10For details about the JS APIs and sample code, see [SE Management](../../reference/apis-connectivity-kit/js-apis-secureElement.md). 11The following table describes the APIs for accessing SEs. 12 13| API | Description | 14| ---------------------------------- | ------------------------------------------------------------------------------ | 15| createService(): Promise\<SEService> | Creates an **SEService** instance for connecting to all available SEs in the system. | 16| getReaders(): Reader[] | Obtains available SE readers, which include all the SEs on the device. | 17| openSession(): Session | Opens a session to connect to an SE in this reader. This API returns a session instance. | 18| openLogicalChannel(aid: number[]): Promise\<Channel> | Opens a logical channel. This API returns a logical channel instance. | 19| transmit(command: number[]): Promise\<number[]> | Transmits APDU data to this SE. | 20| close(): void | Closes this channel. | 21 22 23## How to Develop 24 25### Accessing an SE 261. Import modules. 272. Check whether the device supports SEs. 283. Access an SE and read or write data. 29 30```ts 31import { omapi } from '@kit.ConnectivityKit'; 32import { BusinessError } from '@kit.BasicServicesKit'; 33import { hilog } from '@kit.PerformanceAnalysisKit'; 34import { AbilityConstant, UIAbility, Want } from '@kit.AbilityKit'; 35 36let seService : omapi.SEService; 37let seReaders : omapi.Reader[]; 38let seSession : omapi.Session; 39let seChannel : omapi.Channel; 40let aidArray : number[] = [0xA0, 0x00, 0x00, 0x00, 0x03, 0x10, 0x10]; 41let p2 : number = 0x00; 42 43export default class EntryAbility extends UIAbility { 44 onCreate(want: Want, launchParam: AbilityConstant.LaunchParam) { 45 hilog.info(0x0000, 'testTag', '%{public}s', 'Ability onCreate'); 46 47 // Check whether the device supports SEs. 48 if (!canIUse("SystemCapability.Communication.SecureElement")) { 49 hilog.error(0x0000, 'testTag', 'secure element unavailable.'); 50 return; 51 } 52 hilog.info(0x0000, 'testTag', 'secure element available.'); 53 this.omaTest(); 54 } 55 56 private async omaTest () { 57 // Obtain the service. 58 await omapi.createService().then((data) => { 59 if (data == undefined || !data.isConnected()) { 60 hilog.error(0x0000, 'testTag', 'secure element service disconnected.'); 61 return; 62 } 63 seService = data; 64 hilog.info(0x0000, 'testTag', 'secure element service connected.'); 65 }).catch((error: BusinessError) => { 66 hilog.error(0x0000, 'testTag', 'createService error %{public}s', JSON.stringify(error)); 67 return; 68 }); 69 70 // get readers 71 try { 72 seReaders = seService.getReaders(); 73 } catch (error) { 74 hilog.error(0x0000, 'testTag', 'getReaders error %{public}s', JSON.stringify(error)); 75 } 76 if (seReaders == undefined || seReaders.length == 0) { 77 hilog.error(0x0000, 'testTag', 'no valid reader found.'); 78 seService.shutdown(); 79 return; 80 } 81 let reader: (omapi.Reader | undefined); 82 for (let i = 0; i < seReaders.length; ++i) { 83 let r = seReaders[i]; 84 if (r.getName().includes("SIM")) { 85 reader = r; 86 break; 87 } 88 } 89 if (reader == undefined) { 90 hilog.error(0x0000, 'testTag', 'no valid sim reader.'); 91 return; 92 } 93 hilog.info(0x0000, 'testTag', 'reader is %{public}s', reader?.getName()); 94 95 // get session 96 try { 97 seSession = reader?.openSession() as omapi.Session; 98 } catch (error) { 99 hilog.error(0x0000, 'testTag', 'openSession error %{public}s', JSON.stringify(error)); 100 } 101 if (seSession == undefined) { 102 hilog.error(0x0000, 'testTag', 'seSession invalid.'); 103 seService.shutdown(); 104 return; 105 } 106 107 // get channel 108 try { 109 // change the aid value for open logical channel. 110 seChannel = await seSession.openLogicalChannel(aidArray, p2); 111 } catch (exception) { 112 hilog.error(0x0000, 'testTag', 'openLogicalChannel exception %{public}s', JSON.stringify(exception)); 113 } 114 115 if (seChannel == undefined) { 116 hilog.error(0x0000, 'testTag', 'seChannel invalid.'); 117 return; 118 } 119 120 // transmit data 121 let cmdData = [0x01, 0x02, 0x03, 0x04]; // please change the raw data to be correct. 122 try { 123 let response: number[] = await seChannel.transmit(cmdData) 124 hilog.info(0x0000, 'testTag', 'seChannel.transmit() response = %{public}s.', JSON.stringify(response)); 125 } catch (exception) { 126 hilog.error(0x0000, 'testTag', 'seChannel.transmit() exception = %{public}s.', JSON.stringify(exception)); 127 } 128 129 // close channel. must make sure the channel is closed at last. 130 try { 131 seChannel.close(); 132 } catch (exception) { 133 hilog.error(0x0000, 'testTag', 'seChannel.close() exception = %{public}s.', JSON.stringify(exception)); 134 } 135 136 } 137} 138 139``` 140