iOS开发--使用RSA加密

　在iOS中使用RSA加密解密，需要用到.der和.p12后缀格式的文件，其中.der格式的文件存放的是公钥（Public key）用于加密，.p12格式的文件存放的是私钥（Private key）用于解密. 首先需要先生成这些文件，然后再将文件导入工程使用，不多说，开始做！

一、使用openssl生成所需秘钥文件

　　生成环境是在mac系统下，使用openssl进行生成，首先打开终端，按下面这些步骤依次来做：

1. 生成模长为1024bit的私钥文件`private_key.pem`

openssl genrsa -out private_key.pem 1024

2. 生成证书请求文件`rsaCertReq.csr`

openssl req -new -key private_key.pem -out rsaCerReq.csr

注意：这一步会提示输入国家、省份、mail等信息，可以根据实际情况填写，或者全部不用填写，直接全部敲回车.

3. 生成证书`rsaCert.crt`，并设置有效时间为1年

openssl x509 -req -days 3650 -in rsaCerReq.csr -signkey private_key.pem -out rsaCert.crt

4. 生成供iOS使用的公钥文件`public_key.der`

openssl x509 -outform der -in rsaCert.crt -out public_key.der

5. 生成供iOS使用的私钥文件`private_key.p12`

openssl pkcs12 -export -out private_key.p12 -inkey private_key.pem -in rsaCert.crt

注意：这一步会提示给私钥文件设置密码，直接输入想要设置密码即可，然后敲回车，然后再验证刚才设置的密码，再次输入密码，然后敲回车，完毕！
在解密时，private_key.p12文件需要和这里设置的密码配合使用，因此需要牢记此密码.

6. 生成供Java使用的公钥`rsa_public_key.pem`

openssl rsa -in private_key.pem -out rsa_public_key.pem -pubout

7. 生成供Java使用的私钥`pkcs8_private_key.pem`

openssl pkcs8 -topk8 -in private_key.pem -out pkcs8_private_key.pem -nocrypt

全部执行成功后，会生成如下文件，其中public_key.der和private_key.p12就是iOS需要用到的文件，如下图：

生成的文件

二、将文件导入工程使用

1.新建工程, 并导入`Security.framework`框架, 如下图:

新建工程并添加框架

2.导入秘钥文件

导入.der和.p12格式的秘钥文件, 如下图:

导入秘钥文件

3.新建用于加密、解密的类`RSAEncryptor`, 并实现相关方法

新建RSAEncryptor类, 如下图:

新建用于加密解密的类

下面开始上代码, 可以直接复制过去用:
RSAEncryptor.h代码如下:

#import <Foundation/Foundation.h>

@interface RSAEncryptor : NSObject

/**

 *  加密方法

 *

 *  @param str   需要加密的字符串

 *  @param path  '.der'格式的公钥文件路径

 */

+ (NSString *)encryptString:(NSString *)str publicKeyWithContentsOfFile:(NSString *)path;

/**

 *  解密方法

 *

 *  @param str       需要解密的字符串

 *  @param path      '.p12'格式的私钥文件路径

 *  @param password  私钥文件密码

 */

+ (NSString *)decryptString:(NSString *)str privateKeyWithContentsOfFile:(NSString *)path password:(NSString *)password;

/**

 *  加密方法

 *

 *  @param str    需要加密的字符串

 *  @param pubKey 公钥字符串

 */

+ (NSString *)encryptString:(NSString *)str publicKey:(NSString *)pubKey;

/**

 *  解密方法

 *

 *  @param str     需要解密的字符串

 *  @param privKey 私钥字符串

 */

+ (NSString *)decryptString:(NSString *)str privateKey:(NSString *)privKey;

@end

RSAEncryptor.m代码如下:

#import "RSAEncryptor.h"

#import <Security/Security.h>

@implementation RSAEncryptor

static NSString *base64_encode_data(NSData *data){

    data = [data base64EncodedDataWithOptions:0];

    NSString *ret = [[NSString alloc] initWithData:data encoding:NSUTF8StringEncoding];

    return ret;

}

static NSData *base64_decode(NSString *str){

    NSData *data = [[NSData alloc] initWithBase64EncodedString:str options:NSDataBase64DecodingIgnoreUnknownCharacters];

    return data;

}

#pragma mark - 使用'.der'公钥文件加密

//加密

+ (NSString *)encryptString:(NSString *)str publicKeyWithContentsOfFile:(NSString *)path{

    if (!str || !path)  return nil;

    return [self encryptString:str publicKeyRef:[self getPublicKeyRefWithContentsOfFile:path]];

}

//获取公钥

+ (SecKeyRef)getPublicKeyRefWithContentsOfFile:(NSString *)filePath{

    NSData *certData = [NSData dataWithContentsOfFile:filePath];

    if (!certData) {

        return nil;

    }

    SecCertificateRef cert = SecCertificateCreateWithData(NULL, (CFDataRef)certData);

    SecKeyRef key = NULL;

    SecTrustRef trust = NULL;

    SecPolicyRef policy = NULL;

    if (cert != NULL) {

        policy = SecPolicyCreateBasicX509();

        if (policy) {

            if (SecTrustCreateWithCertificates((CFTypeRef)cert, policy, &trust) == noErr) {

                SecTrustResultType result;

                if (SecTrustEvaluate(trust, &result) == noErr) {

                    key = SecTrustCopyPublicKey(trust);

                }

            }

        }

    }

    if (policy) CFRelease(policy);

    if (trust) CFRelease(trust);

    if (cert) CFRelease(cert);

    return key;

}

+ (NSString *)encryptString:(NSString *)str publicKeyRef:(SecKeyRef)publicKeyRef{

    if(![str dataUsingEncoding:NSUTF8StringEncoding]){

        return nil;

    }

    if(!publicKeyRef){

        return nil;

    }

    NSData *data = [self encryptData:[str dataUsingEncoding:NSUTF8StringEncoding] withKeyRef:publicKeyRef];

    NSString *ret = base64_encode_data(data);

    return ret;

}

#pragma mark - 使用'.12'私钥文件解密

//解密

+ (NSString *)decryptString:(NSString *)str privateKeyWithContentsOfFile:(NSString *)path password:(NSString *)password{

    if (!str || !path) return nil;

    if (!password) password = @"";

    return [self decryptString:str privateKeyRef:[self getPrivateKeyRefWithContentsOfFile:path password:password]];

}

//获取私钥

+ (SecKeyRef)getPrivateKeyRefWithContentsOfFile:(NSString *)filePath password:(NSString*)password{

    NSData *p12Data = [NSData dataWithContentsOfFile:filePath];

    if (!p12Data) {

        return nil;

    }

    SecKeyRef privateKeyRef = NULL;

    NSMutableDictionary * options = [[NSMutableDictionary alloc] init];

    [options setObject: password forKey:(__bridge id)kSecImportExportPassphrase];

    CFArrayRef items = CFArrayCreate(NULL, 0, 0, NULL);

    OSStatus securityError = SecPKCS12Import((__bridge CFDataRef) p12Data, (__bridge CFDictionaryRef)options, &items);

    if (securityError == noErr && CFArrayGetCount(items) > 0) {

        CFDictionaryRef identityDict = CFArrayGetValueAtIndex(items, 0);

        SecIdentityRef identityApp = (SecIdentityRef)CFDictionaryGetValue(identityDict, kSecImportItemIdentity);

        securityError = SecIdentityCopyPrivateKey(identityApp, &privateKeyRef);

        if (securityError != noErr) {

            privateKeyRef = NULL;

        }

    }

    CFRelease(items);

    return privateKeyRef;

}

+ (NSString *)decryptString:(NSString *)str privateKeyRef:(SecKeyRef)privKeyRef{

    NSData *data = [[NSData alloc] initWithBase64EncodedString:str options:NSDataBase64DecodingIgnoreUnknownCharacters];

    if (!privKeyRef) {

        return nil;

    }

    data = [self decryptData:data withKeyRef:privKeyRef];

    NSString *ret = [[NSString alloc] initWithData:data encoding:NSUTF8StringEncoding];

    return ret;

}

#pragma mark - 使用公钥字符串加密

/* START: Encryption with RSA public key */

//使用公钥字符串加密

+ (NSString *)encryptString:(NSString *)str publicKey:(NSString *)pubKey{

    NSData *data = [self encryptData:[str dataUsingEncoding:NSUTF8StringEncoding] publicKey:pubKey];

    NSString *ret = base64_encode_data(data);

    return ret;

}

+ (NSData *)encryptData:(NSData *)data publicKey:(NSString *)pubKey{

    if(!data || !pubKey){

        return nil;

    }

    SecKeyRef keyRef = [self addPublicKey:pubKey];

    if(!keyRef){

        return nil;

    }

    return [self encryptData:data withKeyRef:keyRef];

}

+ (SecKeyRef)addPublicKey:(NSString *)key{

    NSRange spos = [key rangeOfString:@"-----BEGIN PUBLIC KEY-----"];

    NSRange epos = [key rangeOfString:@"-----END PUBLIC KEY-----"];

    if(spos.location != NSNotFound && epos.location != NSNotFound){

        NSUInteger s = spos.location + spos.length;

        NSUInteger e = epos.location;

        NSRange range = NSMakeRange(s, e-s);

        key = [key substringWithRange:range];

    }

    key = [key stringByReplacingOccurrencesOfString:@"\r" withString:@""];

    key = [key stringByReplacingOccurrencesOfString:@"\n" withString:@""];

    key = [key stringByReplacingOccurrencesOfString:@"\t" withString:@""];

    key = [key stringByReplacingOccurrencesOfString:@" "  withString:@""];

    // This will be base64 encoded, decode it.

    NSData *data = base64_decode(key);

    data = [self stripPublicKeyHeader:data];

    if(!data){

        return nil;

    }

    //a tag to read/write keychain storage

    NSString *tag = @"RSAUtil_PubKey";

    NSData *d_tag = [NSData dataWithBytes:[tag UTF8String] length:[tag length]];

    // Delete any old lingering key with the same tag

    NSMutableDictionary *publicKey = [[NSMutableDictionary alloc] init];

    [publicKey setObject:(__bridge id) kSecClassKey forKey:(__bridge id)kSecClass];

    [publicKey setObject:(__bridge id) kSecAttrKeyTypeRSA forKey:(__bridge id)kSecAttrKeyType];

    [publicKey setObject:d_tag forKey:(__bridge id)kSecAttrApplicationTag];

    SecItemDelete((__bridge CFDictionaryRef)publicKey);

    // Add persistent version of the key to system keychain

    [publicKey setObject:data forKey:(__bridge id)kSecValueData];

    [publicKey setObject:(__bridge id) kSecAttrKeyClassPublic forKey:(__bridge id)

     kSecAttrKeyClass];

    [publicKey setObject:[NSNumber numberWithBool:YES] forKey:(__bridge id)

     kSecReturnPersistentRef];

    CFTypeRef persistKey = nil;

    OSStatus status = SecItemAdd((__bridge CFDictionaryRef)publicKey, &persistKey);

    if (persistKey != nil){

        CFRelease(persistKey);

    }

    if ((status != noErr) && (status != errSecDuplicateItem)) {

        return nil;

    }

    [publicKey removeObjectForKey:(__bridge id)kSecValueData];

    [publicKey removeObjectForKey:(__bridge id)kSecReturnPersistentRef];

    [publicKey setObject:[NSNumber numberWithBool:YES] forKey:(__bridge id)kSecReturnRef];

    [publicKey setObject:(__bridge id) kSecAttrKeyTypeRSA forKey:(__bridge id)kSecAttrKeyType];

    // Now fetch the SecKeyRef version of the key

    SecKeyRef keyRef = nil;

    status = SecItemCopyMatching((__bridge CFDictionaryRef)publicKey, (CFTypeRef *)&keyRef);

    if(status != noErr){

        return nil;

    }

    return keyRef;

}

+ (NSData *)stripPublicKeyHeader:(NSData *)d_key{

    // Skip ASN.1 public key header

    if (d_key == nil) return(nil);

    unsigned long len = [d_key length];

    if (!len) return(nil);

    unsigned char *c_key = (unsigned char *)[d_key bytes];

    unsigned int  idx     = 0;

    if (c_key[idx++] != 0x30) return(nil);

    if (c_key[idx] > 0x80) idx += c_key[idx] - 0x80 + 1;

    else idx++;

    // PKCS #1 rsaEncryption szOID_RSA_RSA

    static unsigned char seqiod[] =

    { 0x30,   0x0d, 0x06, 0x09, 0x2a, 0x86, 0x48, 0x86, 0xf7, 0x0d, 0x01, 0x01,

        0x01, 0x05, 0x00 };

    if (memcmp(&c_key[idx], seqiod, 15)) return(nil);

    idx += 15;

    if (c_key[idx++] != 0x03) return(nil);

    if (c_key[idx] > 0x80) idx += c_key[idx] - 0x80 + 1;

    else idx++;

    if (c_key[idx++] != '\0') return(nil);

    // Now make a new NSData from this buffer

    return ([NSData dataWithBytes:&c_key[idx] length:len - idx]);

}

+ (NSData *)encryptData:(NSData *)data withKeyRef:(SecKeyRef) keyRef{

    const uint8_t *srcbuf = (const uint8_t *)[data bytes];

    size_t srclen = (size_t)data.length;

    size_t block_size = SecKeyGetBlockSize(keyRef) * sizeof(uint8_t);

    void *outbuf = malloc(block_size);

    size_t src_block_size = block_size - 11;

    NSMutableData *ret = [[NSMutableData alloc] init];

    for(int idx=0; idx<srclen; idx+=src_block_size){

        //NSLog(@"%d/%d block_size: %d", idx, (int)srclen, (int)block_size);

        size_t data_len = srclen - idx;

        if(data_len > src_block_size){

            data_len = src_block_size;

        }

        size_t outlen = block_size;

        OSStatus status = noErr;

        status = SecKeyEncrypt(keyRef,

                               kSecPaddingPKCS1,

                               srcbuf + idx,

                               data_len,

                               outbuf,

                               &outlen

                               );

        if (status != 0) {

            NSLog(@"SecKeyEncrypt fail. Error Code: %d", status);

            ret = nil;

            break;

        }else{

            [ret appendBytes:outbuf length:outlen];

        }

    }

    free(outbuf);

    CFRelease(keyRef);

    return ret;

}

/* END: Encryption with RSA public key */

#pragma mark - 使用私钥字符串解密

/* START: Decryption with RSA private key */

//使用私钥字符串解密

+ (NSString *)decryptString:(NSString *)str privateKey:(NSString *)privKey{

    if (!str) return nil;

    NSData *data = [[NSData alloc] initWithBase64EncodedString:str options:NSDataBase64DecodingIgnoreUnknownCharacters];

    data = [self decryptData:data privateKey:privKey];

    NSString *ret = [[NSString alloc] initWithData:data encoding:NSUTF8StringEncoding];

    return ret;

}

+ (NSData *)decryptData:(NSData *)data privateKey:(NSString *)privKey{

    if(!data || !privKey){

        return nil;

    }

    SecKeyRef keyRef = [self addPrivateKey:privKey];

    if(!keyRef){

        return nil;

    }

    return [self decryptData:data withKeyRef:keyRef];

}

+ (SecKeyRef)addPrivateKey:(NSString *)key{

    NSRange spos = [key rangeOfString:@"-----BEGIN RSA PRIVATE KEY-----"];

    NSRange epos = [key rangeOfString:@"-----END RSA PRIVATE KEY-----"];

    if(spos.location != NSNotFound && epos.location != NSNotFound){

        NSUInteger s = spos.location + spos.length;

        NSUInteger e = epos.location;

        NSRange range = NSMakeRange(s, e-s);

        key = [key substringWithRange:range];

    }

    key = [key stringByReplacingOccurrencesOfString:@"\r" withString:@""];

    key = [key stringByReplacingOccurrencesOfString:@"\n" withString:@""];

    key = [key stringByReplacingOccurrencesOfString:@"\t" withString:@""];

    key = [key stringByReplacingOccurrencesOfString:@" "  withString:@""];

    // This will be base64 encoded, decode it.

    NSData *data = base64_decode(key);

    data = [self stripPrivateKeyHeader:data];

    if(!data){

        return nil;

    }

    //a tag to read/write keychain storage

    NSString *tag = @"RSAUtil_PrivKey";

    NSData *d_tag = [NSData dataWithBytes:[tag UTF8String] length:[tag length]];

    // Delete any old lingering key with the same tag

    NSMutableDictionary *privateKey = [[NSMutableDictionary alloc] init];

    [privateKey setObject:(__bridge id) kSecClassKey forKey:(__bridge id)kSecClass];

    [privateKey setObject:(__bridge id) kSecAttrKeyTypeRSA forKey:(__bridge id)kSecAttrKeyType];

    [privateKey setObject:d_tag forKey:(__bridge id)kSecAttrApplicationTag];

    SecItemDelete((__bridge CFDictionaryRef)privateKey);

    // Add persistent version of the key to system keychain

    [privateKey setObject:data forKey:(__bridge id)kSecValueData];

    [privateKey setObject:(__bridge id) kSecAttrKeyClassPrivate forKey:(__bridge id)

     kSecAttrKeyClass];

    [privateKey setObject:[NSNumber numberWithBool:YES] forKey:(__bridge id)

     kSecReturnPersistentRef];

    CFTypeRef persistKey = nil;

    OSStatus status = SecItemAdd((__bridge CFDictionaryRef)privateKey, &persistKey);

    if (persistKey != nil){

        CFRelease(persistKey);

    }

    if ((status != noErr) && (status != errSecDuplicateItem)) {

        return nil;

    }

    [privateKey removeObjectForKey:(__bridge id)kSecValueData];

    [privateKey removeObjectForKey:(__bridge id)kSecReturnPersistentRef];

    [privateKey setObject:[NSNumber numberWithBool:YES] forKey:(__bridge id)kSecReturnRef];

    [privateKey setObject:(__bridge id) kSecAttrKeyTypeRSA forKey:(__bridge id)kSecAttrKeyType];

    // Now fetch the SecKeyRef version of the key

    SecKeyRef keyRef = nil;

    status = SecItemCopyMatching((__bridge CFDictionaryRef)privateKey, (CFTypeRef *)&keyRef);

    if(status != noErr){

        return nil;

    }

    return keyRef;

}

+ (NSData *)stripPrivateKeyHeader:(NSData *)d_key{

    // Skip ASN.1 private key header

    if (d_key == nil) return(nil);

    unsigned long len = [d_key length];

    if (!len) return(nil);

    unsigned char *c_key = (unsigned char *)[d_key bytes];

    unsigned int  idx     = 22; //magic byte at offset 22

    if (0x04 != c_key[idx++]) return nil;

    //calculate length of the key

    unsigned int c_len = c_key[idx++];

    int det = c_len & 0x80;

    if (!det) {

        c_len = c_len & 0x7f;

    } else {

        int byteCount = c_len & 0x7f;

        if (byteCount + idx > len) {

            //rsa length field longer than buffer

            return nil;

        }

        unsigned int accum = 0;

        unsigned char *ptr = &c_key[idx];

        idx += byteCount;

        while (byteCount) {

            accum = (accum << 8) + *ptr;

            ptr++;

            byteCount--;

        }

        c_len = accum;

    }

    // Now make a new NSData from this buffer

    return [d_key subdataWithRange:NSMakeRange(idx, c_len)];

}

+ (NSData *)decryptData:(NSData *)data withKeyRef:(SecKeyRef) keyRef{

    const uint8_t *srcbuf = (const uint8_t *)[data bytes];

    size_t srclen = (size_t)data.length;

    size_t block_size = SecKeyGetBlockSize(keyRef) * sizeof(uint8_t);

    UInt8 *outbuf = malloc(block_size);

    size_t src_block_size = block_size;

    NSMutableData *ret = [[NSMutableData alloc] init];

    for(int idx=0; idx<srclen; idx+=src_block_size){

        //NSLog(@"%d/%d block_size: %d", idx, (int)srclen, (int)block_size);

        size_t data_len = srclen - idx;

        if(data_len > src_block_size){

            data_len = src_block_size;

        }

        size_t outlen = block_size;

        OSStatus status = noErr;

        status = SecKeyDecrypt(keyRef,

                               kSecPaddingNone,

                               srcbuf + idx,

                               data_len,

                               outbuf,

                               &outlen

                               );

        if (status != 0) {

            NSLog(@"SecKeyEncrypt fail. Error Code: %d", status);

            ret = nil;

            break;

        }else{

            //the actual decrypted data is in the middle, locate it!

            int idxFirstZero = -1;

            int idxNextZero = (int)outlen;

            for ( int i = 0; i < outlen; i++ ) {

                if ( outbuf[i] == 0 ) {

                    if ( idxFirstZero < 0 ) {

                        idxFirstZero = i;

                    } else {

                        idxNextZero = i;

                        break;

                    }

                }

            }

            [ret appendBytes:&outbuf[idxFirstZero+1] length:idxNextZero-idxFirstZero-1];

        }

    }

    free(outbuf);

    CFRelease(keyRef);

    return ret;

}

/* END: Decryption with RSA private key */

@end

4. 测试加密、解密

首先先测试使用.der和.p12秘钥文件进行加密、解密, 在ViewController.m中进行测试, 代码如下:

#import "ViewController.h"

#import "RSAEncryptor.h"

@interface ViewController ()

@end

@implementation ViewController

- (void)viewDidLoad {

    [super viewDidLoad];

    //原始数据

    NSString *originalString = @"这是一段将要使用'.der'文件加密的字符串!";

    //使用.der和.p12中的公钥私钥加密解密

    NSString *public_key_path = [[NSBundle mainBundle] pathForResource:@"public_key.der" ofType:nil];

    NSString *private_key_path = [[NSBundle mainBundle] pathForResource:@"private_key.p12" ofType:nil];

    NSString *encryptStr = [RSAEncryptor encryptString:originalString publicKeyWithContentsOfFile:public_key_path];

    NSLog(@"加密前:%@", originalString);

    NSLog(@"加密后:%@", encryptStr);

    NSLog(@"解密后:%@", [RSAEncryptor decryptString:encryptStr privateKeyWithContentsOfFile:private_key_path password:@"123456"]);

}

- (void)didReceiveMemoryWarning {

    [super didReceiveMemoryWarning];

    // Dispose of any resources that can be recreated.

}

@end

运行后, 输出信息如下:

输出结果

可以看到已经可以成功加密、解密了.

下面接着测试使用秘钥字符串进行加密、解密, 那么秘钥字符串从哪里来? 可以来这里:http://web.chacuo.net/netrsakeypair, 这是一个在线生成RSA秘钥的网站, 生成公钥和秘钥后, 复制出来用于测试. 然后在ViewController.m中使用RSAEntryptor.h头文件中对应的加密方法进行加密, ViewController.m中代码如下:

#import "ViewController.h"

#import "RSAEncryptor.h"

@interface ViewController ()

@end

@implementation ViewController

- (void)viewDidLoad {

    [super viewDidLoad];

    //原始数据

    NSString *originalString = @"这是一段将要使用'秘钥字符串'进行加密的字符串!";

    //使用字符串格式的公钥私钥加密解密

    NSString *encryptStr = [RSAEncryptor encryptString:originalString publicKey:@"MIGfMA0GCSqGSIb3DQEBAQUAA4GNADCBiQKBgQDTbZ6cNH9PgdF60aQKveLz3FTalyzHQwbp601y77SzmGHX3F5NoVUZbdK7UMdoCLK4FBziTewYD9DWvAErXZo9BFuI96bAop8wfl1VkZyyHTcznxNJFGSQd/B70/ExMgMBpEwkAAdyUqIjIdVGh1FQK/4acwS39YXwbS+IlHsPSQIDAQAB"];

    NSLog(@"加密前:%@", originalString);

    NSLog(@"加密后:%@", encryptStr);

    NSLog(@"解密后:%@", [RSAEncryptor decryptString:encryptStr privateKey:@"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"]);

}

- (void)didReceiveMemoryWarning {

    [super didReceiveMemoryWarning];

    // Dispose of any resources that can be recreated.

}

@end

运行后, 输出信息如下:

输出结果

可以看到,也成功加密、解密了.

至此, RSA加密演示完毕!

文／jianshu_wl（简书作者）
原文链接：http://www.jianshu.com/p/74a796ec5038
著作权归作者所有，转载请联系作者获得授权，并标注“简书作者”。