RSA加密算法是一种非对称加密算法
RSA算法是第一个能同时用于加密和数字签名的算法，也易于理解和操作
DES全称为Data Encryption Standard，即数据加密标准，是一种使用密钥加密的块算法，1977年被美国联邦政府的国家标准局确定为联邦资料处理标准（FIPS），并授权在非密级政府通信中使用，随后该算法在国际上广泛流传开来。需要注意的是，在某些文献中，作为算法的DES称为数据加密算法（Data Encryption Algorithm,DEA），已与作为标准的DES区分开来。
废话少说，贴代码，亲测可用
.h文件的实现
//
// Cryptor.h
//
//
#import
@interface Cryptor : NSObject
/*AES加密
*key传16进制String类型
*/
+ (NSData *)AES128EncryptWithKeyStr:(NSString *)key iv:(NSString *)iv data:(NSData *)data;
+ (NSData *)AES128DecryptWithKeyStr:(NSString *)key iv:(NSString *)iv data:(NSData *)data;
/*AES解密
*key传NSData类型
*/
+ (NSData *)AES128EncryptWithKey:(NSData *)key iv:(NSData *)iv data:(NSData *)data;
+ (NSData *)AES128DecryptWithKey:(NSData *)key iv:(NSData *)iv data:(NSData *)data;
/*RSA加密
*传data和pubKey
*return raw data
*/
+ (NSData *)RSAencryptData:(NSData *)data publicKey:(NSString *)pubKey;
/*RSA加密
*传data和privKey
*return raw data
*/
+ (NSData *)RSAencryptData:(NSData *)data privateKey:(NSString *)privKey;
/*RSA解密
*传data和pubKey
*return raw data
*/
+ (NSData *)RSAdecryptData:(NSData *)data publicKey:(NSString *)pubKey;
/*RSA解密
*传data和privKey
*return raw data
*/
+ (NSData *)RSAdecryptData:(NSData *)data privateKey:(NSString *)privKey;
+ (NSString *)loadPubKeyWithPemName:(NSString *)pemName;
/*
*data转16进制字符串
*/
+ (NSString *)hexEncoding:(NSData*)data;
/*
*16进制转NSData
*/
+ (NSData *)hexDecoding:(NSString *)string;
@end
.m文件实现
//
// Cryptor.m
//
#import "Cryptor.h"
#import
#import "TVTools.h"
@implementation Cryptor
+ (NSData *)AES128EncryptWithKeyStr:(NSString *)key iv:(NSString *)iv data:(NSData *)data {
NSData *keyPtr = [Cryptor hexDecoding:key];
NSData *ivPtr = [Cryptor hexDecoding:iv];
NSUInteger dataLength = [data length];
size_t bufferSize = dataLength + kCCBlockSizeAES128;
void *buffer = malloc(bufferSize);
size_t numBytesEncrypted = 0;
CCCryptorStatus cryptStatus = CCCrypt(kCCEncrypt,
kCCAlgorithmAES128,
kCCOptionPKCS7Padding,
keyPtr.bytes,
kCCBlockSizeAES128,
ivPtr.bytes,
[data bytes],
dataLength,
buffer,
bufferSize,
&numBytesEncrypted);
if (cryptStatus == kCCSuccess) {
return [NSData dataWithBytesNoCopy:buffer length:numBytesEncrypted];
}
free(buffer);
return nil;
}
+ (NSData *)AES128DecryptWithKeyStr:(NSString *)key iv:(NSString *)iv data:(NSData *)data {
NSData *keyPtr = [Cryptor hexDecoding:key];
NSData *ivPtr = [Cryptor hexDecoding:iv];
NSUInteger dataLength = [data length];
size_t bufferSize = dataLength + kCCBlockSizeAES128;
void *buffer = malloc(bufferSize);
size_t numBytesDecrypted = 0;
CCCryptorStatus cryptStatus = CCCrypt(kCCDecrypt,
kCCAlgorithmAES128,
kCCOptionPKCS7Padding,
keyPtr.bytes,
kCCBlockSizeAES128,
ivPtr.bytes,
[data bytes],
dataLength,
buffer,
bufferSize,
&numBytesDecrypted);
if (cryptStatus == kCCSuccess) {
return [NSData dataWithBytesNoCopy:buffer length:numBytesDecrypted];
}
free(buffer);
return nil;
}
+ (NSData *)AES128EncryptWithKey:(NSData *)key iv:(NSData *)iv data:(NSData *)data {
NSUInteger dataLength = [data length];
size_t bufferSize = dataLength + kCCBlockSizeAES128;
void *buffer = malloc(bufferSize);
size_t numBytesEncrypted = 0;
CCCryptorStatus cryptStatus = CCCrypt(kCCEncrypt,
kCCAlgorithmAES128,
kCCOptionPKCS7Padding,
key.bytes,
kCCBlockSizeAES128,
iv.bytes,
[data bytes],
dataLength,
buffer,
bufferSize,
&numBytesEncrypted);
if (cryptStatus == kCCSuccess) {
return [NSData dataWithBytesNoCopy:buffer length:numBytesEncrypted];
}
free(buffer);
return nil;
}
+ (NSData *)AES128DecryptWithKey:(NSData *)key iv:(NSData *)iv data:(NSData *)data {
NSUInteger dataLength = [data length];
size_t bufferSize = dataLength + kCCBlockSizeAES128;
void *buffer = malloc(bufferSize);
size_t numBytesDecrypted = 0;
CCCryptorStatus cryptStatus = CCCrypt(kCCDecrypt,
kCCAlgorithmAES128,
kCCOptionPKCS7Padding,
key.bytes,
kCCBlockSizeAES128,
iv.bytes,
[data bytes],
dataLength,
buffer,
bufferSize,
&numBytesDecrypted);
if (cryptStatus == kCCSuccess) {
return [NSData dataWithBytesNoCopy:buffer length:numBytesDecrypted];
}
free(buffer);
return nil;
}
/*RSA加密
*传data和pubKey
*return raw data
*/
+ (NSData *)RSAencryptData:(NSData *)data publicKey:(NSString *)pubKey{
if(!data || !pubKey){
return nil;
}
SecKeyRef keyRef = [Cryptor addPublicKey:pubKey];
if(!keyRef){
return nil;
}
return [Cryptor encryptData:data withKeyRef:keyRef isSign:NO];
}
/*RSA加密
*传data和privKey
*return raw data
*/
+ (NSData *)RSAencryptData:(NSData *)data privateKey:(NSString *)privKey{
if(!data || !privKey){
return nil;
}
SecKeyRef keyRef = [Cryptor addPrivateKey:privKey];
if(!keyRef){
return nil;
}
return [Cryptor encryptData:data withKeyRef:keyRef isSign:YES];
}
/*RSA解密
*传data和pubKey
*return raw data
*/
+ (NSData *)RSAdecryptData:(NSData *)data publicKey:(NSString *)pubKey{
if(!data || !pubKey){
return nil;
}
SecKeyRef keyRef = [Cryptor addPublicKey:pubKey];
if(!keyRef){
return nil;
}
return [Cryptor decryptData:data withKeyRef:keyRef];
}
/*RSA解密
*传data和privKey
*return raw data
*/
+ (NSData *)RSAdecryptData:(NSData *)data privateKey:(NSString *)privKey{
if(!data || !privKey){
return nil;
}
SecKeyRef keyRef = [Cryptor addPrivateKey:privKey];
if(!keyRef){
return nil;
}
return [Cryptor decryptData:data withKeyRef:keyRef];
}
+ (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 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;
}
/* START: Encryption & Decryption with RSA private key */
+ (NSData *)encryptData:(NSData *)data withKeyRef:(SecKeyRef) keyRef isSign:(BOOL)isSign {
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 src_block_size){
data_len = src_block_size;
}
size_t outlen = block_size;
OSStatus status = noErr;
if (isSign) {
status = SecKeyRawSign(keyRef,
kSecPaddingPKCS1,
srcbuf + idx,
data_len,
outbuf,
&outlen
);
} else {
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;
}
+ (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 = [Cryptor 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 *)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)];
}
+ (SecKeyRef)addPrivateKey:(NSString *)key{
NSRange spos;
NSRange epos;
spos = [key rangeOfString:@"-----BEGIN RSA PRIVATE KEY-----"];
if(spos.length > 0){
epos = [key rangeOfString:@"-----END RSA PRIVATE KEY-----"];
}else{
spos = [key rangeOfString:@"-----BEGIN PRIVATE KEY-----"];
epos = [key rangeOfString:@"-----END 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 = [Cryptor 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;
}
+ (NSString *)loadPubKeyWithPemName:(NSString *)pemName {
NSString *fileName = [[NSBundle mainBundle] pathForResource:pemName ofType:@"pem"];
NSData *certData = [NSData dataWithContentsOfFile:fileName];
return [[NSString alloc]initWithData:certData encoding:NSUTF8StringEncoding];
}
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;
}
//data -> 16进制字符串
+ (NSString *)hexEncoding:(NSData*)data {
const unsigned char *dataBuffer = (const unsigned char *)[data bytes];
if (!dataBuffer) return [NSString string];
NSUInteger dataLength = [data length];
NSMutableString *hexString = [NSMutableString stringWithCapacity:(dataLength * 2)];
for (int i = 0; i < dataLength; ++i)
[hexString appendString:[NSString stringWithFormat:@"%02lx", (unsigned long)dataBuffer[i]]];
return [NSString stringWithString:hexString];
}
// 16进制转NSData
+ (NSData *)hexDecoding:(NSString *)string
{
string = [string lowercaseString];
NSMutableData *data= [NSMutableData new];
unsigned char whole_byte;
char byte_chars[3] = {'\0','\0','\0'};
int i = 0;
int length = string.length;
while (i < length-1) {
char c = [string characterAtIndex:i++];
if (c < '0' || (c > '9' && c < 'a') || c > 'f')
continue;
byte_chars[0] = c;
byte_chars[1] = [string characterAtIndex:i++];
whole_byte = strtol(byte_chars, NULL, 16);
[data appendBytes:&whole_byte length:1];
}
return data;
}
@end
生成RSA公钥和私钥的命令，亲测ok
openssl genrsa -out private_key.pem 1024
openssl req -new -key private_key.pem -out rsaCertReq.csr
openssl x509 -req -days 3650 -in rsaCertReq.csr -signkey private_key.pem -out rsaCert.crt
openssl x509 -outform der -in rsaCert.crt -out public_key.der // Create public_key.der For IOS
openssl pkcs12 -export -out private_key.p12 -inkey private_key.pem -in rsaCert.crt // Create private_key.p12 For IOS. 这一步，请记住你输入的密码，IOS代码里会用到
openssl rsa -in private_key.pem -out rsa_public_key.pem -pubout // Create rsa_public_key.pem For Java
openssl pkcs8 -topk8 -in private_key.pem -out pkcs8_private_key.pem -nocrypt // Create pkcs8_private_key.pem For Java
那些年趟过的坑
发现公司生成的密钥不是以上命令生成的，而是通过java代码生成的，并不是PKCS8，说是PKCS11，所以，上面代码公钥解密的时候，需要替换成以下方法
+ (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 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];
[ret appendBytes:&outbuf[idxFirstZero+1] length:outlen-idxFirstZero-1];
}
}
free(outbuf);
CFRelease(keyRef);
return ret;
}