使用自定义URL方案在两个iOS应用程序之间安全地传输数据+;加密的URL查询字段

使用自定义URL方案在两个iOS应用程序之间安全地传输数据+;加密的URL查询字段,ios,objective-c,security,encryption,Ios,Objective C,Security,Encryption,我将在这里列出我的代码,并希望您告诉我,我在两个应用程序之间传输机密用户数据的方法是否安全。我们公司非常重视安全问题,所以请帮我弄清楚我是否做对了 首先,我使用一个自定义URL方案让应用程序a启动应用程序B,并在两者之间传输一些数据。当通过URL启动时,应用程序B将检查应用程序a的身份,并且仅在应用程序a被授权发送此类数据的情况下使用传输的数据 我在应用程序a中获取密码和用户名,将它们编码为数据,加密数据,将NSData描述转换为字符串,然后在URL请求中发送。我创建了一个名为LaunchEko

我将在这里列出我的代码,并希望您告诉我,我在两个应用程序之间传输机密用户数据的方法是否安全。我们公司非常重视安全问题,所以请帮我弄清楚我是否做对了

首先,我使用一个自定义URL方案让应用程序a启动应用程序B,并在两者之间传输一些数据。当通过URL启动时,应用程序B将检查应用程序a的身份,并且仅在应用程序a被授权发送此类数据的情况下使用传输的数据

我在应用程序a中获取密码和用户名,将它们编码为数据,加密数据,将NSData描述转换为字符串,然后在URL请求中发送。我创建了一个名为LaunchEkoApp的对象,它使用launchEkoAppWithUsername方法处理这个问题

// This is called by my main class in App A
- (void)banishUserToOtherApp
{
    LaunchEkoApp *launcher = [[LaunchEkoApp alloc] init];
    [launcher launchEkoAppWithUsername:@"?!+=WhateverUsernameYouWant=+!?" password:@"123456"];
    @autoreleasepool {
        launcher = nil;
    }
}
LaunchEkoApp对象中的相关代码如下:

#import "LaunchEkoApp.h"
#import "NSData+AESCrypt.h"// Encrypt data for transfer between apps
#import <UIKit/UIKit.h> // Used to launch URL

@implementation LaunchEkoApp

#pragma mark - Encrypt Methods

- (void) launchEkoAppWithUsername: (NSString*) username password:(NSString*) password{
    NSData *uData = [[NSData alloc] initWithData:[[username dataUsingEncoding:NSUTF8StringEncoding] AES256EncryptWithKey:@"superSecretPassword"]];
    NSData *pData = [[NSData alloc] initWithData:[[password dataUsingEncoding:NSUTF8StringEncoding] AES256EncryptWithKey:@"superSecretPassword"]];

    NSString* customURL = [NSString stringWithFormat:@"ekoeko://?U=%@&C=%@", [self formatURLArgumentString:[[[uData.description stringByReplacingOccurrencesOfString:@"<" withString:@""] stringByReplacingOccurrencesOfString:@">" withString:@""] stringByReplacingOccurrencesOfString:@" " withString:@"_"]], [self formatURLArgumentString:[[[pData.description stringByReplacingOccurrencesOfString:@"<" withString:@""] stringByReplacingOccurrencesOfString:@">" withString:@""] stringByReplacingOccurrencesOfString:@" " withString:@"_"]]];

    @autoreleasepool { // Release encripted data. Important!
        uData = nil;
        pData = nil;
    }

    [[UIApplication sharedApplication] openURL:[NSURL URLWithString:customURL]];
}

#pragma mark - Decrypt Methods

-(NSString *) decryptStringFromDataDescription: (NSString *) description{
    return [[NSString alloc] initWithData:[[[NSData data] getNSDataFromNSDataDescription:description] AES256DecryptWithKey:@"superSecretPassword"] encoding:NSUTF8StringEncoding];
}

-(NSString *) decryptStringFromData: (NSData *) data{
    return [[NSString alloc] initWithData:[data AES256DecryptWithKey:@"superSecretPassword"] encoding:NSUTF8StringEncoding];
}

#pragma mark - Helper Methods

-(NSString*) formatURLArgumentString:(NSString*) theString{
    NSMutableCharacterSet * URLQueryPartAllowedCharacterSet; // possibly defined in class extension ...

    // ... and built in init or on first use
    URLQueryPartAllowedCharacterSet = [[NSCharacterSet URLQueryAllowedCharacterSet] mutableCopy];
    [URLQueryPartAllowedCharacterSet removeCharactersInString:@"&+=?"]; // %26, %3D, %3F

    // then escape variables in the URL, such as values in the query and any fragment:
    NSString * escapedValue = [theString stringByAddingPercentEncodingWithAllowedCharacters:URLQueryPartAllowedCharacterSet];

    //[self.delegate logString: [NSString stringWithFormat:@"%@ --> %@", theString, escapedValue]];

    return escapedValue;
}

@end
#导入“LaunchEkoApp.h”
#导入“NSData+AESCrypt.h”//Encrypt数据以在应用程序之间传输
#导入//用于启动URL
@实现启动应用程序
#pragma标记-加密方法
-(void)launchEkoAppWithUsername:(NSString*)用户名密码:(NSString*)密码{
NSData*uData=[[NSData alloc]initWithData:[[username dataUsingEncoding:NSUTF8StringEncoding]AES256EncryptWithKey:@“superSecretPassword”];
NSData*pData=[[NSData alloc]initWithData:[[password dataUsingEncoding:NSUTF8StringEncoding]AES256EncryptWithKey:@“superSecretPassword”];
NSString*customURL=[NSString stringWithFormat:@“ekoeko://?U=%@&C=%@],[self-FormatturArgumentString:[[[uData.description StringByReplacingOccurrences sofString:@”“with String:@”“]StringByReplacingOccurrencessofString:@”“with String:@”“with String:@”“with String:@”],[self-FormatturArgumentArgumentString:[[[pData.description StringByReplacingOccurReplacingOccurcessofString:@]]stringByReplacingOccurrencesOfString:@“with string:@”“]];
@自动释放池{//释放加密数据。重要!
uData=零;
pData=零;
}
[[UIApplication sharedApplication]openURL:[NSURL URLWithString:customURL]];
}
#pragma标记-解密方法
-(NSString*)decryptStringFromDataDescription:(NSString*)说明{
返回[[NSString alloc]initWithData:[[NSData data]getNSDataFromNSDataDescription:description]AES256DecryptWithKey:@“superSecretPassword”]编码:NSUTF8StringEncoding];
}
-(NSString*)解密StringFromData:(NSData*)数据{
返回[[NSString alloc]initWithData:[data AES256DecryptWithKey:@“superSecretPassword”]编码:NSUTF8StringEncoding];
}
#pragma-mark-Helper方法
-(NSString*)formatURLArgumentString:(NSString*)字符串{
NSMutableCharacterSet*URLQueryPartAllowedCharacterSet;//可能在类扩展中定义。。。
//…并内置于init或首次使用时
URLQueryPartAllowedCharacterSet=[[NSCharacterSet URLQueryAllowedCharacterSet]可变副本];
[URLQueryPartAllowedCharacterSet removeCharactersInString:@“&+=?”];//%26,%3D,%3F
//然后在URL中转义变量,例如查询中的值和任何片段:
NSString*escapedValue=[theString stringByAddingPercentEncodingWithAllowedCharacters:URLQueryPartAllowedCharacterSet];
//[self.delegate日志字符串:[NSString stringWithFormat:@“%@-->%@”,字符串,转义值];
返回转义值;
}
@结束
这里可以看到我用来加密用户名/密码字符串NSData的代码(请参阅AES256EncryptWithKey,不要担心,我会在生产中使用更好的加密密码):

//NSData+AESCrypt.m
#导入“NSData+AESCrypt.h”
#进口
静态字符编码表[64]=
{
‘A’、‘B’、‘C’、‘D’、‘E’、‘F’、‘G’、‘H’、‘I’、‘J’、‘K’、‘L’、‘M’、‘N’、‘O’、‘P’,
‘Q’、‘R’、‘S’、‘T’、‘U’、‘V’、‘W’、‘X’、‘Y’、‘Z’、‘a’、‘b’、‘c’、‘d’、‘e’、‘f’,
‘g’、‘h’、‘i’、‘j’、‘k’、‘l’、‘m’、‘n’、‘o’、‘p’、‘q’、‘r’、‘s’、‘t’、‘u’、‘v’,
‘w’、‘x’、‘y’、‘z’、‘0’、‘1’、‘2’、‘3’、‘4’、‘5’、‘6’、‘7’、‘8’、‘9’、‘加’、‘/’
};
@实现NSData(AESCrypt)
-(NSData*)AES256EncryptWithKey:(NSString*)密钥{
//AES256的“键”应为32字节,否则将填充为空
char keyPtr[kCCKeySizeAES256+1];//为终止符预留的空间(未使用)
bzero(keyPtr,sizeof(keyPtr));//用零填充(用于填充)
//获取关键数据
[key-getCString:keyPtr-maxLength:sizeof(keyPtr)编码:NSUTF8StringEncoding];
NSU整数数据长度=[自身长度];
//参见文档:对于分组密码,输出大小将始终小于或
//等于输入大小加上一个块的大小。
//这就是为什么我们需要在这里添加一个块的大小
size\u t bufferSize=dataLength+kccblocksizeaaes128;
void*buffer=malloc(bufferSize);
大小\u t numBytesEncrypted=0;
CCCryptorStatus cryptStatus=CCCrypt(kCCEncrypt,kCCAlgorithmAES128,kCCOptionPKCS7Padding,
keyPtr,kCCKeySizeAES256,
NULL/*初始化向量(可选)*/,,
[self bytes],数据长度,/*输入*/
缓冲区,缓冲区大小,/*输出*/
&(未加密);
@自动释放池{
键=零;
}
if(cryptStatus==kCCSuccess)
{
//返回的NSData拥有缓冲区的所有权,并在释放时释放缓冲区
返回[NSData DATAFTHBYTESNOCOPY:缓冲区长度:numBytesEncrypted];
}
释放(缓冲区);//释放缓冲区
返回零;
}
-(NSData*)AES256DecryptWithKey:(NSString*)密钥{
//AES256的“键”应为32字节,否则将填充为空
char keyPtr[kCCKeySizeAES256+1];//为终止符预留的空间(未使用)
bzero(keyPtr,sizeof(keyPtr));//用零填充(用于填充)
//获取关键数据
[key-getCString:keyPtr-maxLength:sizeof(keyPtr)编码:NSUTF8StringEncoding];
NSU整数数据长度=[自身长度];
//参见文档:对于分组密码,输出大小将始终小于或
// NSData+AESCrypt.m

#import "NSData+AESCrypt.h"
#import <CommonCrypto/CommonCryptor.h>

static char encodingTable[64] =
{
    'A','B','C','D','E','F','G','H','I','J','K','L','M','N','O','P',
    'Q','R','S','T','U','V','W','X','Y','Z','a','b','c','d','e','f',
    'g','h','i','j','k','l','m','n','o','p','q','r','s','t','u','v',
    'w','x','y','z','0','1','2','3','4','5','6','7','8','9','+','/'
};

@implementation NSData (AESCrypt)

- (NSData *)AES256EncryptWithKey:(NSString *)key{
    // 'key' should be 32 bytes for AES256, will be null-padded otherwise
    char keyPtr[kCCKeySizeAES256 + 1]; // room for terminator (unused)
    bzero( keyPtr, sizeof( keyPtr ) ); // fill with zeroes (for padding)

    // fetch key data
    [key getCString:keyPtr maxLength:sizeof( keyPtr ) encoding:NSUTF8StringEncoding];

    NSUInteger dataLength = [self length];

    //See the doc: For block ciphers, the output size will always be less than or
    //equal to the input size plus the size of one block.
    //That's why we need to add the size of one block here
    size_t bufferSize = dataLength + kCCBlockSizeAES128;
    void *buffer = malloc( bufferSize );

    size_t numBytesEncrypted = 0;
    CCCryptorStatus cryptStatus = CCCrypt( kCCEncrypt, kCCAlgorithmAES128, kCCOptionPKCS7Padding,
                                          keyPtr, kCCKeySizeAES256,
                                          NULL /* initialization vector (optional) */,
                                          [self bytes], dataLength, /* input */
                                          buffer, bufferSize, /* output */
                                          &numBytesEncrypted );
    @autoreleasepool {
        key = nil;
    }

    if( cryptStatus == kCCSuccess )
    {
        //the returned NSData takes ownership of the buffer and will free it on deallocation
        return [NSData dataWithBytesNoCopy:buffer length:numBytesEncrypted];
    }

    free( buffer ); //free the buffer
    return nil;
}

- (NSData *)AES256DecryptWithKey:(NSString *)key{

    // 'key' should be 32 bytes for AES256, will be null-padded otherwise
    char keyPtr[kCCKeySizeAES256+1]; // room for terminator (unused)
    bzero( keyPtr, sizeof( keyPtr ) ); // fill with zeroes (for padding)

    // fetch key data
    [key getCString:keyPtr maxLength:sizeof( keyPtr ) encoding:NSUTF8StringEncoding];

    NSUInteger dataLength = [self length];

    //See the doc: For block ciphers, the output size will always be less than or
    //equal to the input size plus the size of one block.
    //That's why we need to add the size of one block here
    size_t bufferSize = dataLength + kCCBlockSizeAES128;
    void *buffer = malloc( bufferSize );

    size_t numBytesDecrypted = 0;
    CCCryptorStatus cryptStatus = CCCrypt( kCCDecrypt, kCCAlgorithmAES128, kCCOptionPKCS7Padding,
                                          keyPtr, kCCKeySizeAES256,
                                          NULL /* initialization vector (optional) */,
                                          [self bytes], dataLength, /* input */
                                          buffer, bufferSize, /* output */
                                          &numBytesDecrypted );

    @autoreleasepool {
        key = nil;
    }

    if( cryptStatus == kCCSuccess )
    {
        //the returned NSData takes ownership of the buffer and will free it on deallocation
        return [NSData dataWithBytesNoCopy:buffer length:numBytesDecrypted];
    }

    free( buffer ); //free the buffer
    return nil;
}

# pragma mark -

-(NSData*) getNSDataFromNSDataDescription:(NSString*) dataDescription{
    const char *ptr = [dataDescription cStringUsingEncoding:NSUTF8StringEncoding];

    NSMutableData *encryptedData = [NSMutableData data];

    while (*ptr) {
        unsigned char c1 = *ptr;
        ptr++;
        if (isalpha(c1))
            c1 = (10 + c1 - 'a')<<4;
        else if (isnumber(c1))
            c1 = (c1 - '0')<<4;
        else
            continue;
        if (!*ptr)
            break; // Shouldn't occure -- bad input
        unsigned char c2 = *ptr;
        ptr++;
        if (isalpha(c2))
            c2 = 10 + c2 - 'a';
        else if (isnumber(c2))
            c2 = c2 - '0';
        c1 = c1 | c2;
        [encryptedData appendBytes:&c1 length:1];
    }

    return encryptedData;
}

#pragma mark -

+ (NSData *)dataWithBase64EncodedString:(NSString *)string
{
    return [[NSData allocWithZone:nil] initWithBase64EncodedString:string];
}

- (id)initWithBase64EncodedString:(NSString *)string
{
    NSMutableData *mutableData = nil;

    if( string )
    {
        unsigned long ixtext = 0;
        unsigned long lentext = 0;
        unsigned char ch = 0;
        unsigned char inbuf[4], outbuf[3];
        short i = 0, ixinbuf = 0;
        BOOL flignore = NO;
        BOOL flendtext = NO;
        NSData *base64Data = nil;
        const unsigned char *base64Bytes = nil;

        // Convert the string to ASCII data.
        base64Data = [string dataUsingEncoding:NSASCIIStringEncoding];
        base64Bytes = [base64Data bytes];
        mutableData = [NSMutableData dataWithCapacity:base64Data.length];
        lentext = base64Data.length;

        while( YES )
        {
            if( ixtext >= lentext ) break;
            ch = base64Bytes[ixtext++];
            flignore = NO;

            if( ( ch >= 'A' ) && ( ch <= 'Z' ) ) ch = ch - 'A';
            else if( ( ch >= 'a' ) && ( ch <= 'z' ) ) ch = ch - 'a' + 26;
            else if( ( ch >= '0' ) && ( ch <= '9' ) ) ch = ch - '0' + 52;
            else if( ch == '+' ) ch = 62;
            else if( ch == '=' ) flendtext = YES;
            else if( ch == '/' ) ch = 63;
            else flignore = YES;

            if( ! flignore )
            {
                short ctcharsinbuf = 3;
                BOOL flbreak = NO;

                if( flendtext )
                {
                    if( ! ixinbuf ) break;
                    if( ( ixinbuf == 1 ) || ( ixinbuf == 2 ) ) ctcharsinbuf = 1;
                    else ctcharsinbuf = 2;
                    ixinbuf = 3;
                    flbreak = YES;
                }

                inbuf [ixinbuf++] = ch;

                if( ixinbuf == 4 )
                {
                    ixinbuf = 0;
                    outbuf [0] = ( inbuf[0] << 2 ) | ( ( inbuf[1] & 0x30) >> 4 );
                    outbuf [1] = ( ( inbuf[1] & 0x0F ) << 4 ) | ( ( inbuf[2] & 0x3C ) >> 2 );
                    outbuf [2] = ( ( inbuf[2] & 0x03 ) << 6 ) | ( inbuf[3] & 0x3F );

                    for( i = 0; i < ctcharsinbuf; i++ )
                        [mutableData appendBytes:&outbuf[i] length:1];
                }

                if( flbreak )  break;
            }
        }
    }

    self = [self initWithData:mutableData];
    return self;
}

#pragma mark -

- (NSString *)base64Encoding
{
    return [self base64EncodingWithLineLength:0];
}

- (NSString *)base64EncodingWithLineLength:(NSUInteger)lineLength
{
    const unsigned char   *bytes = [self bytes];
    NSMutableString *result = [NSMutableString stringWithCapacity:self.length];
    unsigned long ixtext = 0;
    unsigned long lentext = self.length;
    long ctremaining = 0;
    unsigned char inbuf[3], outbuf[4];
    unsigned short i = 0;
    unsigned short charsonline = 0, ctcopy = 0;
    unsigned long ix = 0;

    while( YES )
    {
        ctremaining = lentext - ixtext;
        if( ctremaining <= 0 ) break;

        for( i = 0; i < 3; i++ )
        {
            ix = ixtext + i;
            if( ix < lentext ) inbuf[i] = bytes[ix];
            else inbuf [i] = 0;
        }

        outbuf [0] = (inbuf [0] & 0xFC) >> 2;
        outbuf [1] = ((inbuf [0] & 0x03) << 4) | ((inbuf [1] & 0xF0) >> 4);
        outbuf [2] = ((inbuf [1] & 0x0F) << 2) | ((inbuf [2] & 0xC0) >> 6);
        outbuf [3] = inbuf [2] & 0x3F;
        ctcopy = 4;

        switch( ctremaining )
        {
            case 1:
                ctcopy = 2;
                break;
            case 2:
                ctcopy = 3;
                break;
        }

        for( i = 0; i < ctcopy; i++ )
            [result appendFormat:@"%c", encodingTable[outbuf[i]]];

        for( i = ctcopy; i < 4; i++ )
            [result appendString:@"="];

        ixtext += 3;
        charsonline += 4;

        if( lineLength > 0 )
        {
            if( charsonline >= lineLength )
            {
                charsonline = 0;
                [result appendString:@"\n"];
            }
        }
    }

    return [NSString stringWithString:result];
}
#pragma mark -
- (BOOL)hasPrefixBytes:(const void *)prefix length:(NSUInteger)length
{
    if( ! prefix || ! length || self.length < length ) return NO;
    return ( memcmp( [self bytes], prefix, length ) == 0 );
}

- (BOOL)hasSuffixBytes:(const void *)suffix length:(NSUInteger)length
{
    if( ! suffix || ! length || self.length < length ) return NO;
    return ( memcmp( ((const char *)[self bytes] + (self.length - length)), suffix, length ) == 0  );
}
// This is the main class in App B
-(void) appLoadedThroughURLWithQuery: (NSString*) query{
    // Populate sign in fields with that and try to login

    if(_initialLoad || _activeViewController == theSignInVC){
        LaunchEkoApp *launcher = [[LaunchEkoApp alloc] init];
        [_signInVC autoLoginUserWithUsername:[launcher decryptStringFromDataDescription:[NSString stringWithFormat:@"<%@>", [[[query substringToIndex:[query rangeOfString:@"&"].location] stringByReplacingOccurrencesOfString:@"U=" withString:@""] stringByReplacingOccurrencesOfString:@"_" withString:@" "]]] password:[launcher decryptStringFromDataDescription:[NSString stringWithFormat:@"<%@>", [[[query substringFromIndex:[query rangeOfString:@"&"].location+1] stringByReplacingOccurrencesOfString:@"C=" withString:@""] stringByReplacingOccurrencesOfString:@"_" withString:@" "]]]];
        @autoreleasepool {
            launcher = nil;
        }
    }

    // Get username/credential
    //NSString *credential = [[NSString alloc] initWithData:[[self getNSDataFromNSDataDescription:[NSString stringWithFormat:@"<%@>", [[[query substringFromIndex:[query rangeOfString:@"&"].location+1] stringByReplacingOccurrencesOfString:@"C=" withString:@""] stringByReplacingOccurrencesOfString:@"_" withString:@" "]]] AES256DecryptWithKey:@"superSecretPassword"] encoding:NSUTF8StringEncoding];;
    //NSString *username = [[NSString alloc] initWithData:[[self getNSDataFromNSDataDescription:[NSString stringWithFormat:@"<%@>", [[[query substringToIndex:[query rangeOfString:@"&"].location] stringByReplacingOccurrencesOfString:@"U=" withString:@""] stringByReplacingOccurrencesOfString:@"_" withString:@" "]]] AES256DecryptWithKey:@"superSecretPassword"] encoding:NSUTF8StringEncoding];

    @autoreleasepool {
        query = nil;
    }
}