指纹验证完整版处理小结

　　在ios中指纹的使用相对比较简单，但是在使用的过程中遇到以下几个问题，故对指纹使用进行简单封装，以处理这些问题，问题如下：

　　　　1、ios 9之后系统指纹被锁，系统不会主动弹出密码解锁的页面

　　　 2、ios 10.*系统不区分指纹未录入和密码未设置的情况

　　处理逻辑如下:

　　

　　处理部分代码如下：

----------------------------.h文件

/*
 1、处理iOS 9.0之后，指纹被锁不会自动弹出密码解锁的情况；
 2、处理iOS 10.*系统不区分未录入指纹和未设置密码的情况；
 */
#import <Foundation/Foundation.h>

typedef NS_ENUM(NSInteger, TITouchIDVerificationError) {
    TITouchIDVerificationErrorLocalizedReason,
    TITouchIDVerificationErrorAuthFailMessage,
    TITouchIDVerificationErrorNotAvailableMessage,
    TITouchIDVerificationErrorNotEnrolledMessage,
    TITouchIDVerificationErrorLockOut,
    TITouchIDVerificationErrorPasscodeNotSetMessage,
    TITouchIDVerificationErrorUserCancel,
    TITouchIDVerificationErrorAppCancel,
    TITouchIDVerificationErrorUnknown
};

typedef NS_ENUM(NSInteger, TIVerificationStatus) {
    TIVerificationStatusSuccess,
    TIVerificationStatusPasswordNotSet,
    TIVerificationStatusNotEncrolled,
    TIVerificationStatusFailed,
    TIVerificationStatusFallback,
    TIVerificationStatusLockOut,
    TIVerificationStatusCancel,
    TIVerificationStatusError,
};

typedef void(^VerificationCompletion)(TIVerificationStatus status, NSError *error);

@interface LYYTouchID : NSObject


/**
 调用TouchID

 @param completion 验证完成,如果返回YES,验证成功;如果返回NO,验证失败(输入密码和指纹验证失败)
 */
+ (void)touchVerificationWithFallbackTitle:(NSString*)fallbackTitle completion:(VerificationCompletion)completion;
@end


---------------------------.m文件

#import "LYYTouchID.h"
#import <UIKit/UIKit.h>
#import <LocalAuthentication/LocalAuthentication.h>

#define TI_IS_iOS_LATER(num)  ([UIDevice currentDevice].systemVersion.floatValue >= (num))
#define TI_IS_iOS8_LATER  TI_IS_iOS_LATER(8.0)
#define TI_IS_iOS9_LATER  TI_IS_iOS_LATER(9.0)
#define TI_IS_iOS10_LATER  TI_IS_iOS_LATER(10.0)
#define TI_IS_iOS11_LATER  TI_IS_iOS_LATER(11.0)

NSString * const TouchIDLocalizedReason = @"请您验证已有TouchID";
NSString * const TouchIDNotAvailableMessage = @"您当前设备不支持TouchID";
NSString * const TouchIDNotEnrolledMessage = @"您当前没有录入指纹信息";
NSString * const TouchIDNotCorrectMessage = @"您的指纹信息不匹配";
NSString * const TouchIDPasscodeNotSetMessage = @"您当前没有设置密码";
NSString * const TouchIDCancelMessage = @"您已取消验证TouchID";
NSString * const TouchIDUnknownErrorMessage = @"出现未知错误";
NSString * const TouchIDLockOutMessage = @"TouchID 被锁定";

static BOOL _isTouchIDLocked;//用于存储第一遍canEvaluatePolicy检查到的指纹被锁的状态
static BOOL _touchIDSecondCheck;//用于存储canEvaluatePolicy是否是第二次查询

@interface LYYTouchID ()
@end


@implementation LYYTouchID

#pragma mark - 验证
+ (void)touchVerificationWithFallbackTitle:(NSString*)fallbackTitle completion:(VerificationCompletion)completion{
    LAContext *context = [[LAContext alloc] init];
    context.localizedFallbackTitle = fallbackTitle?:@"";
    LAPolicy policy = [self setPolicy];
    
    NSError *notSupportError = nil;
    if ([context canEvaluatePolicy:policy error:&notSupportError]) {
        
        //处理10.*系统纯指纹策略不走passwordNotSet方法
        if (_touchIDSecondCheck&&TI_IS_iOS10_LATER&&!TI_IS_iOS11_LATER) {//第二次检测指纹是否可用（指纹+密码策略），且可以
            _touchIDSecondCheck = NO;
            completion(TIVerificationStatusNotEncrolled,[self returnErrorInfoWithErrorCode:LAErrorTouchIDNotEnrolled]);
            return;
        }
        
        //不是第二次检测指纹是否可用，直接进行验证
        [context evaluatePolicy:policy localizedReason:TouchIDLocalizedReason reply:^(BOOL success, NSError * _Nullable error) {
            
            dispatch_async(dispatch_get_main_queue(), ^{
                if (success) {
                    
                    if (TI_IS_iOS9_LATER&&_isTouchIDLocked) {//TouchID 解锁成功时，更改为纯指纹策略，验证TouchID
                        _isTouchIDLocked = NO;
                        [self touchVerificationWithFallbackTitle:fallbackTitle completion:completion];
                    }else{//ios9.0之前版本不支持密码策略直接返回信息
                        _isTouchIDLocked = NO;
                        completion(TIVerificationStatusSuccess,nil);
                    }
                }
                else {
                    int code = (int)error.code;
                    ////设置锁定状态为NO
                    _isTouchIDLocked = NO;
                    [self dealErrorWithErrorCode:code fallbackTitle:fallbackTitle complection:completion];
                }

            });
            
        }];
    }else {
        
        [self dealErrorWithErrorCode:(int)notSupportError.code fallbackTitle:fallbackTitle complection:completion];
    }
}
#pragma mark - 设置指纹策略
+ (LAPolicy)setPolicy{
    LAPolicy policy;
    
    if (_touchIDSecondCheck&&TI_IS_iOS9_LATER){//已经查验过纯指纹策略，且纯指纹策略不支持，改变策略为指纹+密码进行二次验证
        policy = LAPolicyDeviceOwnerAuthentication;
        return policy;
    }
    if (_isTouchIDLocked&&TI_IS_iOS9_LATER) {//指纹被锁定且系统大于9.0，使用“指纹+密码”策略
        policy = LAPolicyDeviceOwnerAuthentication;
    }else{//使用“指纹”策略（默认是指纹策略）
        policy = LAPolicyDeviceOwnerAuthenticationWithBiometrics;
    }
    return policy;
}
#pragma mark - 处理不同错误
+ (void)dealErrorWithErrorCode:(int)code fallbackTitle:(NSString*)fallbackTitle complection:(VerificationCompletion)completion{
    
    switch (code) {
        case LAErrorUserFallback:
            completion(TIVerificationStatusFallback,[self returnErrorInfoWithErrorCode:code]);
            break;
            
        case LAErrorAuthenticationFailed:
            completion(TIVerificationStatusFailed,[self returnErrorInfoWithErrorCode:code]);
            break;
            
        case LAErrorSystemCancel:{
            _isTouchIDLocked = NO;
            _touchIDSecondCheck = NO;
        }
            break;
         
        case LAErrorPasscodeNotSet:
            _isTouchIDLocked = NO;
            _touchIDSecondCheck = NO;
            completion(TIVerificationStatusPasswordNotSet,[self returnErrorInfoWithErrorCode:code]);
            break;
            
        case LAErrorTouchIDNotAvailable:
            
            break;
  
        case LAErrorAppCancel:{
            _isTouchIDLocked = NO;
            _touchIDSecondCheck = NO;
        }
            break;
        case LAErrorUserCancel:
            _isTouchIDLocked = NO;
            _touchIDSecondCheck = NO;
            completion(TIVerificationStatusCancel,[self returnErrorInfoWithErrorCode:code]);
            break;

        default: {
            if (TI_IS_iOS9_LATER) {
                if (code==LAErrorTouchIDLockout) {
                    //ios9.0更改为密码策略，解锁TouchID
                    _isTouchIDLocked = YES;
                    [self touchVerificationWithFallbackTitle:fallbackTitle completion:completion];
                    break;

                }
            }
            if (TI_IS_iOS8_LATER&&!TI_IS_iOS11_LATER) {
                if (code==LAErrorTouchIDNotEnrolled) {
                    //处理ios 10.*系统不走passwordNotSet
                    if (TI_IS_iOS10_LATER&&!_touchIDSecondCheck) {//ios 9.0之后，第一次返回指纹不可用的结果（这时是纯指纹策略）
                        _touchIDSecondCheck = YES;
                        [self touchVerificationWithFallbackTitle:fallbackTitle completion:completion];
                    }else{
                        //ios 9.0 之后是第二次返回不可用结果，此时采用的是指纹+密码策略，此时指纹确实不可用
                        //ios 9.0 之前，第一次返回指纹不可用的结果，此时直接返回指纹不可用的错误
                        _touchIDSecondCheck = NO;
                        completion(TIVerificationStatusNotEncrolled,[self returnErrorInfoWithErrorCode:code]);
                    }
                    
                    break;
                }
            }
            if (@available(iOS 11.0, *)) {
                if (code==LAErrorBiometryNotEnrolled) {
                    completion(TIVerificationStatusNotEncrolled,[self returnErrorInfoWithErrorCode:code]);
                    break;
                }
            }
            
            completion(TIVerificationStatusError,[self returnErrorInfoWithErrorCode:code]);
        }
            break;
            
    }
}

#pragma mark - 生成error
+ (NSError *)returnErrorInfoWithErrorCode:(int)errorCode {
    
    if (TI_IS_iOS9_LATER) {
        if (errorCode == LAErrorAppCancel) {
            NSError *tempError = [NSError errorWithDomain:@"TouchIDVerfityDomain" code:TITouchIDVerificationErrorAppCancel userInfo:@{@"message":TouchIDCancelMessage}];
            return tempError;
        }
    }
    
    NSString *errorMessage = @"";
    NSUInteger errCode = 0;
    
    switch (errorCode) {
        case LAErrorTouchIDNotAvailable:
            errorMessage = TouchIDNotAvailableMessage;
            errCode = TITouchIDVerificationErrorNotAvailableMessage;
            break;
        case LAErrorAuthenticationFailed:
            errorMessage = TouchIDNotCorrectMessage;
            errCode = TITouchIDVerificationErrorAuthFailMessage;
            break;
        case LAErrorPasscodeNotSet:
            errorMessage = TouchIDPasscodeNotSetMessage;
            errCode = TITouchIDVerificationErrorPasscodeNotSetMessage;
            break;
        case LAErrorUserCancel:
            errorMessage = TouchIDCancelMessage;
            errCode = TITouchIDVerificationErrorUserCancel;
            break;
        default:
            if (TI_IS_iOS9_LATER) {
                if (errorCode==LAErrorTouchIDLockout) {
                    errorMessage = TouchIDLockOutMessage;
                    errCode = TITouchIDVerificationErrorLockOut;
                    break;
                }
            }
            if (TI_IS_iOS8_LATER&&!TI_IS_iOS11_LATER) {
                if (errorCode==LAErrorTouchIDNotEnrolled) {
                    errorMessage = TouchIDNotEnrolledMessage;
                    errCode = TITouchIDVerificationErrorNotEnrolledMessage;
                    break;
                }
            }
            if (@available(iOS 11.0, *)) {
                if (errorCode==LAErrorBiometryNotEnrolled) {
                    errorMessage = TouchIDNotEnrolledMessage;
                    errCode = TITouchIDVerificationErrorNotEnrolledMessage;
                    break;
                }
            }
            errorMessage = TouchIDUnknownErrorMessage;
            errCode = TITouchIDVerificationErrorUnknown;
            break;
    }
    
    NSError *tempError = [NSError errorWithDomain:@"TouchIDVerfityDomain" code:errCode userInfo:@{@"message":errorMessage}];
    //
    return tempError;
}
@end