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kevinchl/Readme.markdown

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Created June 4, 2012 08:02
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Revisions

  1. @gonecoding gonecoding revised this gist Mar 23, 2012. 1 changed file with 3 additions and 1 deletion.
    4 changes: 3 additions & 1 deletion Readme.markdown
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    @@ -1,4 +1,6 @@
    # Important notice

    I took down this Gist due to concerns about the security of the encryption/decryption part of this code (see comments below). Rob Napier (@rnapier) has created a publicly available class that provides AES encryption/decryption functionality at https://github.com/rnapier/RNCryptor.
    I took down this Gist due to concerns about the security of the encryption/decryption part of this code (see comments below).

    Rob Napier (@rnapier) has created a publicly available class that provides similar AES encryption/decryption functionality at https://github.com/rnapier/RNCryptor.

  2. @gonecoding gonecoding revised this gist Mar 23, 2012. 4 changed files with 0 additions and 336 deletions.
    31 changes: 0 additions & 31 deletions NSData+AESCrypt.h
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    Original file line number Diff line number Diff line change
    @@ -1,31 +0,0 @@
    //
    // NSData+AESCrypt.h
    //
    // AES Encrypt/Decrypt
    // Created by Jim Dovey and 'Jean'
    // See http://iphonedevelopment.blogspot.com/2009/02/strong-encryption-for-cocoa-cocoa-touch.html
    //
    // BASE64 Encoding/Decoding
    // Copyright (c) 2001 Kyle Hammond. All rights reserved.
    // Original development by Dave Winer.
    //
    // Put together by Michael Sedlaczek, Gone Coding on 2011-02-22
    //

    #import <Foundation/Foundation.h>

    @interface NSData (AESCrypt)

    - (NSData *)AES256EncryptWithKey:(NSString *)key;
    - (NSData *)AES256DecryptWithKey:(NSString *)key;

    + (NSData *)dataWithBase64EncodedString:(NSString *)string;
    - (id)initWithBase64EncodedString:(NSString *)string;

    - (NSString *)base64Encoding;
    - (NSString *)base64EncodingWithLineLength:(NSUInteger)lineLength;

    - (BOOL)hasPrefixBytes:(const void *)prefix length:(NSUInteger)length;
    - (BOOL)hasSuffixBytes:(const void *)suffix length:(NSUInteger)length;

    @end
    259 changes: 0 additions & 259 deletions NSData+AESCrypt.m
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    @@ -1,259 +0,0 @@
    //
    // NSData+AESCrypt.m
    //
    // AES Encrypt/Decrypt
    // Created by Jim Dovey and 'Jean'
    // See http://iphonedevelopment.blogspot.com/2009/02/strong-encryption-for-cocoa-cocoa-touch.html
    //
    // BASE64 Encoding/Decoding
    // Copyright (c) 2001 Kyle Hammond. All rights reserved.
    // Original development by Dave Winer.
    //
    // Put together by Michael Sedlaczek, Gone Coding on 2011-02-22
    //

    #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 );
    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 );

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

    - (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 );
    }

    @end
    15 changes: 0 additions & 15 deletions NSString+AESCrypt.h
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    @@ -1,15 +0,0 @@
    //
    // NSString+AESCrypt.h
    //
    // Created by Michael Sedlaczek, Gone Coding on 2011-02-22
    //

    #import <Foundation/Foundation.h>
    #import "NSData+AESCrypt.h"

    @interface NSString (AESCrypt)

    - (NSString *)AES256EncryptWithKey:(NSString *)key;
    - (NSString *)AES256DecryptWithKey:(NSString *)key;

    @end
    31 changes: 0 additions & 31 deletions NSString+AESCrypt.m
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    //
    // NSString+AESCrypt.m
    //
    // Created by Michael Sedlaczek, Gone Coding on 2011-02-22
    //

    #import "NSString+AESCrypt.h"

    @implementation NSString (AESCrypt)

    - (NSString *)AES256EncryptWithKey:(NSString *)key
    {
    NSData *plainData = [self dataUsingEncoding:NSUTF8StringEncoding];
    NSData *encryptedData = [plainData AES256EncryptWithKey:key];

    NSString *encryptedString = [encryptedData base64Encoding];

    return encryptedString;
    }

    - (NSString *)AES256DecryptWithKey:(NSString *)key
    {
    NSData *encryptedData = [NSData dataWithBase64EncodedString:self];
    NSData *plainData = [encryptedData AES256DecryptWithKey:key];

    NSString *plainString = [[NSString alloc] initWithData:plainData encoding:NSUTF8StringEncoding];

    return [plainString autorelease];
    }

    @end
  3. @gonecoding gonecoding revised this gist Mar 23, 2012. 4 changed files with 0 additions and 12 deletions.
    3 changes: 0 additions & 3 deletions NSDataAESCrypt.h
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    //
    // Removed. See notice above.
    //
    3 changes: 0 additions & 3 deletions NSDataAESCrypt.m
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    //
    // Removed. See notice above.
    //
    3 changes: 0 additions & 3 deletions NSStringAESCrypt.h
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    //
    // Removed. See notice above.
    //
    3 changes: 0 additions & 3 deletions NSStringAESCrypt.m
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    //
    // Removed. See notice above.
    //
  4. @gonecoding gonecoding revised this gist Mar 23, 2012. 1 changed file with 1 addition and 3 deletions.
    4 changes: 1 addition & 3 deletions Readme.markdown
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    @@ -1,6 +1,4 @@
    # Important notice

    I took down this Gist due to concerns about the security of the encryption/decryption part of this code (see comments below).

    Rob Napier (@rnapier) has created a publicly available class that provides AES encryption/decryption functionality at https://github.com/rnapier/RNCryptor.
    I took down this Gist due to concerns about the security of the encryption/decryption part of this code (see comments below). Rob Napier (@rnapier) has created a publicly available class that provides AES encryption/decryption functionality at https://github.com/rnapier/RNCryptor.

  5. @gonecoding gonecoding revised this gist Mar 23, 2012. 4 changed files with 12 additions and 0 deletions.
    3 changes: 3 additions & 0 deletions NSDataAESCrypt.h
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    @@ -0,0 +1,3 @@
    //
    // Removed. See notice above.
    //
    3 changes: 3 additions & 0 deletions NSDataAESCrypt.m
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    @@ -0,0 +1,3 @@
    //
    // Removed. See notice above.
    //
    3 changes: 3 additions & 0 deletions NSStringAESCrypt.h
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    @@ -0,0 +1,3 @@
    //
    // Removed. See notice above.
    //
    3 changes: 3 additions & 0 deletions NSStringAESCrypt.m
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    @@ -0,0 +1,3 @@
    //
    // Removed. See notice above.
    //
  6. @gonecoding gonecoding revised this gist Mar 23, 2012. No changes.
  7. @gonecoding gonecoding revised this gist Mar 23, 2012. 5 changed files with 2 additions and 336 deletions.
    31 changes: 0 additions & 31 deletions NSDataAESCrypt.h
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    @@ -1,31 +0,0 @@
    //
    // NSData+AESCrypt.h
    //
    // AES Encrypt/Decrypt
    // Created by Jim Dovey and 'Jean'
    // See http://iphonedevelopment.blogspot.com/2009/02/strong-encryption-for-cocoa-cocoa-touch.html
    //
    // BASE64 Encoding/Decoding
    // Copyright (c) 2001 Kyle Hammond. All rights reserved.
    // Original development by Dave Winer.
    //
    // Put together by Michael Sedlaczek, Gone Coding on 2011-02-22
    //

    #import <Foundation/Foundation.h>

    @interface NSData (AESCrypt)

    - (NSData *)AES256EncryptWithKey:(NSString *)key;
    - (NSData *)AES256DecryptWithKey:(NSString *)key;

    + (NSData *)dataWithBase64EncodedString:(NSString *)string;
    - (id)initWithBase64EncodedString:(NSString *)string;

    - (NSString *)base64Encoding;
    - (NSString *)base64EncodingWithLineLength:(NSUInteger)lineLength;

    - (BOOL)hasPrefixBytes:(const void *)prefix length:(NSUInteger)length;
    - (BOOL)hasSuffixBytes:(const void *)suffix length:(NSUInteger)length;

    @end
    259 changes: 0 additions & 259 deletions NSDataAESCrypt.m
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    @@ -1,259 +0,0 @@
    //
    // NSData+AESCrypt.m
    //
    // AES Encrypt/Decrypt
    // Created by Jim Dovey and 'Jean'
    // See http://iphonedevelopment.blogspot.com/2009/02/strong-encryption-for-cocoa-cocoa-touch.html
    //
    // BASE64 Encoding/Decoding
    // Copyright (c) 2001 Kyle Hammond. All rights reserved.
    // Original development by Dave Winer.
    //
    // Put together by Michael Sedlaczek, Gone Coding on 2011-02-22
    //

    #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 );
    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 );

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

    - (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 );
    }

    @end
    15 changes: 0 additions & 15 deletions NSStringAESCrypt.h
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    @@ -1,15 +0,0 @@
    //
    // NSString+AESCrypt.h
    //
    // Created by Michael Sedlaczek, Gone Coding on 2011-02-22
    //

    #import <Foundation/Foundation.h>
    #import "NSData+AESCrypt.h"

    @interface NSString (AESCrypt)

    - (NSString *)AES256EncryptWithKey:(NSString *)key;
    - (NSString *)AES256DecryptWithKey:(NSString *)key;

    @end
    31 changes: 0 additions & 31 deletions NSStringAESCrypt.m
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    @@ -1,31 +0,0 @@
    //
    // NSString+AESCrypt.m
    //
    // Created by Michael Sedlaczek, Gone Coding on 2011-02-22
    //

    #import "NSString+AESCrypt.h"

    @implementation NSString (AESCrypt)

    - (NSString *)AES256EncryptWithKey:(NSString *)key
    {
    NSData *plainData = [self dataUsingEncoding:NSUTF8StringEncoding];
    NSData *encryptedData = [plainData AES256EncryptWithKey:key];

    NSString *encryptedString = [encryptedData base64Encoding];

    return encryptedString;
    }

    - (NSString *)AES256DecryptWithKey:(NSString *)key
    {
    NSData *encryptedData = [NSData dataWithBase64EncodedString:self];
    NSData *plainData = [encryptedData AES256DecryptWithKey:key];

    NSString *plainString = [[NSString alloc] initWithData:plainData encoding:NSUTF8StringEncoding];

    return [plainString autorelease];
    }

    @end
    2 changes: 2 additions & 0 deletions Readme.markdown
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    @@ -1,3 +1,5 @@
    # Important notice

    I took down this Gist due to concerns about the security of the encryption/decryption part of this code (see comments below).

    Rob Napier (@rnapier) has created a publicly available class that provides AES encryption/decryption functionality at https://github.com/rnapier/RNCryptor.
  8. @gonecoding gonecoding revised this gist Mar 23, 2012. 5 changed files with 340 additions and 0 deletions.
    31 changes: 31 additions & 0 deletions NSDataAESCrypt.h
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    @@ -0,0 +1,31 @@
    //
    // NSData+AESCrypt.h
    //
    // AES Encrypt/Decrypt
    // Created by Jim Dovey and 'Jean'
    // See http://iphonedevelopment.blogspot.com/2009/02/strong-encryption-for-cocoa-cocoa-touch.html
    //
    // BASE64 Encoding/Decoding
    // Copyright (c) 2001 Kyle Hammond. All rights reserved.
    // Original development by Dave Winer.
    //
    // Put together by Michael Sedlaczek, Gone Coding on 2011-02-22
    //

    #import <Foundation/Foundation.h>

    @interface NSData (AESCrypt)

    - (NSData *)AES256EncryptWithKey:(NSString *)key;
    - (NSData *)AES256DecryptWithKey:(NSString *)key;

    + (NSData *)dataWithBase64EncodedString:(NSString *)string;
    - (id)initWithBase64EncodedString:(NSString *)string;

    - (NSString *)base64Encoding;
    - (NSString *)base64EncodingWithLineLength:(NSUInteger)lineLength;

    - (BOOL)hasPrefixBytes:(const void *)prefix length:(NSUInteger)length;
    - (BOOL)hasSuffixBytes:(const void *)suffix length:(NSUInteger)length;

    @end
    259 changes: 259 additions & 0 deletions NSDataAESCrypt.m
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    //
    // NSData+AESCrypt.m
    //
    // AES Encrypt/Decrypt
    // Created by Jim Dovey and 'Jean'
    // See http://iphonedevelopment.blogspot.com/2009/02/strong-encryption-for-cocoa-cocoa-touch.html
    //
    // BASE64 Encoding/Decoding
    // Copyright (c) 2001 Kyle Hammond. All rights reserved.
    // Original development by Dave Winer.
    //
    // Put together by Michael Sedlaczek, Gone Coding on 2011-02-22
    //

    #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 );
    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 );

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

    - (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 );
    }

    @end
    15 changes: 15 additions & 0 deletions NSStringAESCrypt.h
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    @@ -0,0 +1,15 @@
    //
    // NSString+AESCrypt.h
    //
    // Created by Michael Sedlaczek, Gone Coding on 2011-02-22
    //

    #import <Foundation/Foundation.h>
    #import "NSData+AESCrypt.h"

    @interface NSString (AESCrypt)

    - (NSString *)AES256EncryptWithKey:(NSString *)key;
    - (NSString *)AES256DecryptWithKey:(NSString *)key;

    @end
    31 changes: 31 additions & 0 deletions NSStringAESCrypt.m
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    @@ -0,0 +1,31 @@
    //
    // NSString+AESCrypt.m
    //
    // Created by Michael Sedlaczek, Gone Coding on 2011-02-22
    //

    #import "NSString+AESCrypt.h"

    @implementation NSString (AESCrypt)

    - (NSString *)AES256EncryptWithKey:(NSString *)key
    {
    NSData *plainData = [self dataUsingEncoding:NSUTF8StringEncoding];
    NSData *encryptedData = [plainData AES256EncryptWithKey:key];

    NSString *encryptedString = [encryptedData base64Encoding];

    return encryptedString;
    }

    - (NSString *)AES256DecryptWithKey:(NSString *)key
    {
    NSData *encryptedData = [NSData dataWithBase64EncodedString:self];
    NSData *plainData = [encryptedData AES256DecryptWithKey:key];

    NSString *plainString = [[NSString alloc] initWithData:plainData encoding:NSUTF8StringEncoding];

    return [plainString autorelease];
    }

    @end
    4 changes: 4 additions & 0 deletions Readme.markdown
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    @@ -0,0 +1,4 @@
    I took down this Gist due to concerns about the security of the encryption/decryption part of this code (see comments below).

    Rob Napier (@rnapier) has created a publicly available class that provides AES encryption/decryption functionality at https://github.com/rnapier/RNCryptor.

  9. @gonecoding gonecoding revised this gist Feb 22, 2011. 1 changed file with 144 additions and 144 deletions.
    288 changes: 144 additions & 144 deletions NSData+AESCrypt.m
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    Original file line number Diff line number Diff line change
    @@ -27,233 +27,233 @@ @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,
    // '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 );
    if( cryptStatus == kCCSuccess )
    if( cryptStatus == kCCSuccess )
    {
    //the returned NSData takes ownership of the buffer and will free it on deallocation
    return [NSData dataWithBytesNoCopy:buffer length:numBytesEncrypted];
    }
    //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;
    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,
    // '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 );
    if( cryptStatus == kCCSuccess )
    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;
    //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 *)dataWithBase64EncodedString:(NSString *)string
    {
    return [[[NSData allocWithZone:nil] initWithBase64EncodedString:string] autorelease];
    return [[[NSData allocWithZone:nil] initWithBase64EncodedString:string] autorelease];
    }

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

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

    while( YES )
    while( YES )
    {
    if( ixtext >= lentext ) break;
    ch = base64Bytes[ixtext++];
    flignore = NO;
    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( ( 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 )
    if( ! flignore )
    {
    short ctcharsinbuf = 3;
    BOOL flbreak = NO;
    short ctcharsinbuf = 3;
    BOOL flbreak = NO;

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

    inbuf [ixinbuf++] = ch;
    inbuf [ixinbuf++] = ch;

    if( ixinbuf == 4 )
    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 );
    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];
    }
    for( i = 0; i < ctcharsinbuf; i++ )
    [mutableData appendBytes:&outbuf[i] length:1];
    }

    if( flbreak ) break;
    }
    }
    }
    if( flbreak ) break;
    }
    }
    }

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

    #pragma mark -

    - (NSString *)base64Encoding
    {
    return [self base64EncodingWithLineLength:0];
    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;
    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 )
    while( YES )
    {
    ctremaining = lentext - ixtext;
    if( ctremaining <= 0 ) break;
    ctremaining = lentext - ixtext;
    if( ctremaining <= 0 ) break;

    for( i = 0; i < 3; i++ )
    for( i = 0; i < 3; i++ )
    {
    ix = ixtext + i;
    if( ix < lentext ) inbuf[i] = bytes[ix];
    else inbuf [i] = 0;
    }
    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;
    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 )
    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 = 0; i < ctcopy; i++ )
    [result appendFormat:@"%c", encodingTable[outbuf[i]]];

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

    ixtext += 3;
    charsonline += 4;
    ixtext += 3;
    charsonline += 4;

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

    return [NSString stringWithString:result];
    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 );
    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 );
    if( ! suffix || ! length || self.length < length ) return NO;
    return ( memcmp( ((const char *)[self bytes] + (self.length - length)), suffix, length ) == 0 );
    }

    @end
  10. @gonecoding gonecoding created this gist Feb 22, 2011.
    31 changes: 31 additions & 0 deletions NSData+AESCrypt.h
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    //
    // NSData+AESCrypt.h
    //
    // AES Encrypt/Decrypt
    // Created by Jim Dovey and 'Jean'
    // See http://iphonedevelopment.blogspot.com/2009/02/strong-encryption-for-cocoa-cocoa-touch.html
    //
    // BASE64 Encoding/Decoding
    // Copyright (c) 2001 Kyle Hammond. All rights reserved.
    // Original development by Dave Winer.
    //
    // Put together by Michael Sedlaczek, Gone Coding on 2011-02-22
    //

    #import <Foundation/Foundation.h>

    @interface NSData (AESCrypt)

    - (NSData *)AES256EncryptWithKey:(NSString *)key;
    - (NSData *)AES256DecryptWithKey:(NSString *)key;

    + (NSData *)dataWithBase64EncodedString:(NSString *)string;
    - (id)initWithBase64EncodedString:(NSString *)string;

    - (NSString *)base64Encoding;
    - (NSString *)base64EncodingWithLineLength:(NSUInteger)lineLength;

    - (BOOL)hasPrefixBytes:(const void *)prefix length:(NSUInteger)length;
    - (BOOL)hasSuffixBytes:(const void *)suffix length:(NSUInteger)length;

    @end
    259 changes: 259 additions & 0 deletions NSData+AESCrypt.m
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    //
    // NSData+AESCrypt.m
    //
    // AES Encrypt/Decrypt
    // Created by Jim Dovey and 'Jean'
    // See http://iphonedevelopment.blogspot.com/2009/02/strong-encryption-for-cocoa-cocoa-touch.html
    //
    // BASE64 Encoding/Decoding
    // Copyright (c) 2001 Kyle Hammond. All rights reserved.
    // Original development by Dave Winer.
    //
    // Put together by Michael Sedlaczek, Gone Coding on 2011-02-22
    //

    #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 );
    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 );

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

    - (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 );
    }

    @end
    15 changes: 15 additions & 0 deletions NSString+AESCrypt.h
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    //
    // NSString+AESCrypt.h
    //
    // Created by Michael Sedlaczek, Gone Coding on 2011-02-22
    //

    #import <Foundation/Foundation.h>
    #import "NSData+AESCrypt.h"

    @interface NSString (AESCrypt)

    - (NSString *)AES256EncryptWithKey:(NSString *)key;
    - (NSString *)AES256DecryptWithKey:(NSString *)key;

    @end
    31 changes: 31 additions & 0 deletions NSString+AESCrypt.m
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    Original file line number Diff line number Diff line change
    @@ -0,0 +1,31 @@
    //
    // NSString+AESCrypt.m
    //
    // Created by Michael Sedlaczek, Gone Coding on 2011-02-22
    //

    #import "NSString+AESCrypt.h"

    @implementation NSString (AESCrypt)

    - (NSString *)AES256EncryptWithKey:(NSString *)key
    {
    NSData *plainData = [self dataUsingEncoding:NSUTF8StringEncoding];
    NSData *encryptedData = [plainData AES256EncryptWithKey:key];

    NSString *encryptedString = [encryptedData base64Encoding];

    return encryptedString;
    }

    - (NSString *)AES256DecryptWithKey:(NSString *)key
    {
    NSData *encryptedData = [NSData dataWithBase64EncodedString:self];
    NSData *plainData = [encryptedData AES256DecryptWithKey:key];

    NSString *plainString = [[NSString alloc] initWithData:plainData encoding:NSUTF8StringEncoding];

    return [plainString autorelease];
    }

    @end