iOS开发之Objective-c的SHA224/SHA256/SHA384/SHA512加密算法的实现

之前在博文中实现的SHA1的安全性已经满足不了用户需求，今天把SHA224/SHA256/SHA384/SHA512的实现一并附上。
SHA即Secure Hash Algorithm（安全散列算法)有多种不同位数的实现，常见的有SHA224/SHA256/SHA384/SHA512等

SHA224:

- (NSString*) sha224
{
    const char *cstr = [self cStringUsingEncoding:NSUTF8StringEncoding];
    NSData *data = [NSData dataWithBytes:cstr length:self.length];
    
    uint8_t digest[CC_SHA224_DIGEST_LENGTH];
    
    CC_SHA224(data.bytes, data.length, digest);
    
    NSMutableString* output = [NSMutableString stringWithCapacity:CC_SHA224_DIGEST_LENGTH * 2];
    
    for(int i = 0; i 

SHA256:
- (NSString*) sha256
{
    const char *cstr = [self cStringUsingEncoding:NSUTF8StringEncoding];
    NSData *data = [NSData dataWithBytes:cstr length:self.length];
    
    uint8_t digest[CC_SHA256_DIGEST_LENGTH];
    
    CC_SHA256(data.bytes, data.length, digest);
    
    NSMutableString* output = [NSMutableString stringWithCapacity:CC_SHA256_DIGEST_LENGTH * 2];
    
    for(int i = 0; i 
SHA384:
- (NSString*) sha384
{
    const char *cstr = [self cStringUsingEncoding:NSUTF8StringEncoding];
    NSData *data = [NSData dataWithBytes:cstr length:self.length];
    
    uint8_t digest[CC_SHA384_DIGEST_LENGTH];
    
    CC_SHA384(data.bytes, data.length, digest);
    
    NSMutableString* output = [NSMutableString stringWithCapacity:CC_SHA384_DIGEST_LENGTH * 2];
    
    for(int i = 0; i 
SHA512:
- (NSString*) sha512
{
    const char *cstr = [self cStringUsingEncoding:NSUTF8StringEncoding];
    NSData *data = [NSData dataWithBytes:cstr length:self.length];
    
    uint8_t digest[CC_SHA512_DIGEST_LENGTH];
    
    CC_SHA512(data.bytes, data.length, digest);
    
    NSMutableString* output = [NSMutableString stringWithCapacity:CC_SHA512_DIGEST_LENGTH * 2];
    
    for(int i = 0; i 
放到一起大团结
//
//NSString+SHA.h
//

#import 
#import 
#import 

@interface NSString(SHA)
-(NSString *) sha1;
-(NSString *) sha224;
-(NSString *) sha256;
-(NSString *) sha384;
-(NSString *) sha512;
@end

//
//NSString+SHA.m
//

#import "NSString+SHA.h"

@implementation NSString(SHA)

- (NSString*) sha1
{
    const char *cstr = [self cStringUsingEncoding:NSUTF8StringEncoding];
    NSData *data = [NSData dataWithBytes:cstr length:self.length];
    
    uint8_t digest[CC_SHA1_DIGEST_LENGTH];
    
    CC_SHA1(data.bytes, data.length, digest);
    
    NSMutableString* output = [NSMutableString stringWithCapacity:CC_SHA1_DIGEST_LENGTH * 2];
    
    for(int i = 0; i