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//注册请求
- (void)postRequest
{//POST请求 请求参数放在请求内部(httpBody)//设置请求NSMutableURLRequest * request = [[NSMutableURLRequest alloc] init];request.timeoutInterval = 10;request.HTTPMethod = @"POST";request.URL = [NSURL URLWithString:@"https://api.cn.rong.io/user/getToken.json"];NSString * appkey = @"你注册的key";NSString * nonce = [NSString stringWithFormat:@"%d",arc4random()];NSString * timestamp = [[NSString alloc] initWithFormat:@"%ld",(NSInteger)[NSDate timeIntervalSinceReferenceDate]];//配置http header[request setValue:appkey forHTTPHeaderField:@"App-Key"];[request setValue:nonce forHTTPHeaderField:@"Nonce"];[request setValue:timestamp forHTTPHeaderField:@"Timestamp"];[request setValue:@"4kr0B8zlhXux" forHTTPHeaderField:@"appSecret"];//生成hashcode 用以验证签名[request setValue:[self sha1:[NSString stringWithFormat:@"%@%@%@",appkey,nonce,timestamp]] forHTTPHeaderField:@"Signature"];[request setValue:@"application/x-www-form-urlencoded" forHTTPHeaderField:@"Content-Type"];NSMutableDictionary * paramDic = [NSMutableDictionary dictionary];[paramDic setObject:_accountField.text forKey:@"userId"];[paramDic setObject:_accountField.text forKey:@"name"];[paramDic setObject:@"一张图片的网络连接" forKey:@"portraitUri"];request.HTTPBody = [self httpBodyFromParamDictionary:paramDic];[NSURLConnection connectionWithRequest:request delegate:self];
}//请求拼接
- (NSData *)httpBodyFromParamDictionary:(NSDictionary *)param
{NSMutableString * data = [NSMutableString string];for (NSString * key in param.allKeys) {[data appendFormat:@"%@=%@&",key,param[key]];}return [[data substringToIndex:data.length-1] dataUsingEncoding:NSUTF8StringEncoding];
}//hash算法
- (NSString*) sha1:(NSString *)hashString
{const char *cstr = [hashString cStringUsingEncoding:NSUTF8StringEncoding];NSData *data = [NSData dataWithBytes:cstr length:hashString.length];uint8_t digest[CC_SHA1_DIGEST_LENGTH];CC_SHA1(data.bytes, (CC_LONG)data.length, digest);NSMutableString* output = [NSMutableString stringWithCapacity:CC_SHA1_DIGEST_LENGTH * 2];for(int i = 0; i < CC_SHA1_DIGEST_LENGTH; i++)[output appendFormat:@"%02x", digest[i]];return output;
}//64位 hash算法
- (NSString *) sha1_base64:(NSString *)hashString
{const char *cstr = [hashString cStringUsingEncoding:NSUTF8StringEncoding];NSData *data = [NSData dataWithBytes:cstr length:hashString.length];uint8_t digest[CC_SHA1_DIGEST_LENGTH];CC_SHA1(data.bytes, (CC_LONG)data.length, digest);NSData * base64 = [[NSData alloc]initWithBytes:digest length:CC_SHA1_DIGEST_LENGTH];base64 = [GTMBase64 encodeData:base64];NSString * output = [[NSString alloc] initWithData:base64 encoding:NSUTF8StringEncoding];return output;
}GTMBase64.h
//
// GTMBase64.h
//
// Copyright 2006-2008 Google Inc.
//
// Licensed under the Apache License, Version 2.0 (the "License"); you may not
// use this file except in compliance with the License. You may obtain a copy
// of the License at
//
// http://www.apache.org/licenses/LICENSE-2.0
//
// Unless required by applicable law or agreed to in writing, software
// distributed under the License is distributed on an "AS IS" BASIS, WITHOUT
// WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the
// License for the specific language governing permissions and limitations under
// the License.
//#import <Foundation/Foundation.h>
#import "GTMDefines.h"// GTMBase64
//
/// Helper for handling Base64 and WebSafeBase64 encodings
//
/// The webSafe methods use different character set and also the results aren't
/// always padded to a multiple of 4 characters. This is done so the resulting
/// data can be used in urls and url query arguments without needing any
/// encoding. You must use the webSafe* methods together, the data does not
/// interop with the RFC methods.
//
@interface GTMBase64 : NSObject//
// Standard Base64 (RFC) handling
//// encodeData:
//
/// Base64 encodes contents of the NSData object.
//
/// Returns:
/// A new autoreleased NSData with the encoded payload. nil for any error.
//
+(NSData *)encodeData:(NSData *)data;// decodeData:
//
/// Base64 decodes contents of the NSData object.
//
/// Returns:
/// A new autoreleased NSData with the decoded payload. nil for any error.
//
+(NSData *)decodeData:(NSData *)data;// encodeBytes:length:
//
/// Base64 encodes the data pointed at by |bytes|.
//
/// Returns:
/// A new autoreleased NSData with the encoded payload. nil for any error.
//
+(NSData *)encodeBytes:(const void *)bytes length:(NSUInteger)length;// decodeBytes:length:
//
/// Base64 decodes the data pointed at by |bytes|.
//
/// Returns:
/// A new autoreleased NSData with the encoded payload. nil for any error.
//
+(NSData *)decodeBytes:(const void *)bytes length:(NSUInteger)length;// stringByEncodingData:
//
/// Base64 encodes contents of the NSData object.
//
/// Returns:
/// A new autoreleased NSString with the encoded payload. nil for any error.
//
+(NSString *)stringByEncodingData:(NSData *)data;// stringByEncodingBytes:length:
//
/// Base64 encodes the data pointed at by |bytes|.
//
/// Returns:
/// A new autoreleased NSString with the encoded payload. nil for any error.
//
+(NSString *)stringByEncodingBytes:(const void *)bytes length:(NSUInteger)length;// decodeString:
//
/// Base64 decodes contents of the NSString.
//
/// Returns:
/// A new autoreleased NSData with the decoded payload. nil for any error.
//
+(NSData *)decodeString:(NSString *)string;//
// Modified Base64 encoding so the results can go onto urls.
//
// The changes are in the characters generated and also allows the result to
// not be padded to a multiple of 4.
// Must use the matching call to encode/decode, won't interop with the
// RFC versions.
//// webSafeEncodeData:padded:
//
/// WebSafe Base64 encodes contents of the NSData object. If |padded| is YES
/// then padding characters are added so the result length is a multiple of 4.
//
/// Returns:
/// A new autoreleased NSData with the encoded payload. nil for any error.
//
+(NSData *)webSafeEncodeData:(NSData *)datapadded:(BOOL)padded;// webSafeDecodeData:
//
/// WebSafe Base64 decodes contents of the NSData object.
//
/// Returns:
/// A new autoreleased NSData with the decoded payload. nil for any error.
//
+(NSData *)webSafeDecodeData:(NSData *)data;// webSafeEncodeBytes:length:padded:
//
/// WebSafe Base64 encodes the data pointed at by |bytes|. If |padded| is YES
/// then padding characters are added so the result length is a multiple of 4.
//
/// Returns:
/// A new autoreleased NSData with the encoded payload. nil for any error.
//
+(NSData *)webSafeEncodeBytes:(const void *)byteslength:(NSUInteger)lengthpadded:(BOOL)padded;// webSafeDecodeBytes:length:
//
/// WebSafe Base64 decodes the data pointed at by |bytes|.
//
/// Returns:
/// A new autoreleased NSData with the encoded payload. nil for any error.
//
+(NSData *)webSafeDecodeBytes:(const void *)bytes length:(NSUInteger)length;// stringByWebSafeEncodingData:padded:
//
/// WebSafe Base64 encodes contents of the NSData object. If |padded| is YES
/// then padding characters are added so the result length is a multiple of 4.
//
/// Returns:
/// A new autoreleased NSString with the encoded payload. nil for any error.
//
+(NSString *)stringByWebSafeEncodingData:(NSData *)datapadded:(BOOL)padded;// stringByWebSafeEncodingBytes:length:padded:
//
/// WebSafe Base64 encodes the data pointed at by |bytes|. If |padded| is YES
/// then padding characters are added so the result length is a multiple of 4.
//
/// Returns:
/// A new autoreleased NSString with the encoded payload. nil for any error.
//
+(NSString *)stringByWebSafeEncodingBytes:(const void *)byteslength:(NSUInteger)lengthpadded:(BOOL)padded;// webSafeDecodeString:
//
/// WebSafe Base64 decodes contents of the NSString.
//
/// Returns:
/// A new autoreleased NSData with the decoded payload. nil for any error.
//
+(NSData *)webSafeDecodeString:(NSString *)string;@end//
// GTMBase64.m
//
// Copyright 2006-2008 Google Inc.
//
// Licensed under the Apache License, Version 2.0 (the "License"); you may not
// use this file except in compliance with the License. You may obtain a copy
// of the License at
//
// http://www.apache.org/licenses/LICENSE-2.0
//
// Unless required by applicable law or agreed to in writing, software
// distributed under the License is distributed on an "AS IS" BASIS, WITHOUT
// WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the
// License for the specific language governing permissions and limitations under
// the License.
//#import "GTMBase64.h"
#import "GTMDefines.h"static const char *kBase64EncodeChars = "ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz0123456789+/";
static const char *kWebSafeBase64EncodeChars = "ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz0123456789-_";
static const char kBase64PaddingChar = '=';
static const char kBase64InvalidChar = 99;static const char kBase64DecodeChars[] = {// This array was generated by the following code:// #include <sys/time.h>// #include <stdlib.h>// #include <string.h>// main()// {// static const char Base64[] =// "ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz0123456789+/";// char *pos;// int idx, i, j;// printf(" ");// for (i = 0; i < 255; i += 8) {// for (j = i; j < i + 8; j++) {// pos = strchr(Base64, j);// if ((pos == NULL) || (j == 0))// idx = 99;// else// idx = pos - Base64;// if (idx == 99)// printf(" %2d, ", idx);// else// printf(" %2d/*%c*/,", idx, j);// }// printf("\n ");// }// }99, 99, 99, 99, 99, 99, 99, 99,99, 99, 99, 99, 99, 99, 99, 99,99, 99, 99, 99, 99, 99, 99, 99,99, 99, 99, 99, 99, 99, 99, 99,99, 99, 99, 99, 99, 99, 99, 99,99, 99, 99, 62/*+*/, 99, 99, 99, 63/*/ */,52/*0*/, 53/*1*/, 54/*2*/, 55/*3*/, 56/*4*/, 57/*5*/, 58/*6*/, 59/*7*/,60/*8*/, 61/*9*/, 99, 99, 99, 99, 99, 99,99, 0/*A*/, 1/*B*/, 2/*C*/, 3/*D*/, 4/*E*/, 5/*F*/, 6/*G*/,7/*H*/, 8/*I*/, 9/*J*/, 10/*K*/, 11/*L*/, 12/*M*/, 13/*N*/, 14/*O*/,15/*P*/, 16/*Q*/, 17/*R*/, 18/*S*/, 19/*T*/, 20/*U*/, 21/*V*/, 22/*W*/,23/*X*/, 24/*Y*/, 25/*Z*/, 99, 99, 99, 99, 99,99, 26/*a*/, 27/*b*/, 28/*c*/, 29/*d*/, 30/*e*/, 31/*f*/, 32/*g*/,33/*h*/, 34/*i*/, 35/*j*/, 36/*k*/, 37/*l*/, 38/*m*/, 39/*n*/, 40/*o*/,41/*p*/, 42/*q*/, 43/*r*/, 44/*s*/, 45/*t*/, 46/*u*/, 47/*v*/, 48/*w*/,49/*x*/, 50/*y*/, 51/*z*/, 99, 99, 99, 99, 99,99, 99, 99, 99, 99, 99, 99, 99,99, 99, 99, 99, 99, 99, 99, 99,99, 99, 99, 99, 99, 99, 99, 99,99, 99, 99, 99, 99, 99, 99, 99,99, 99, 99, 99, 99, 99, 99, 99,99, 99, 99, 99, 99, 99, 99, 99,99, 99, 99, 99, 99, 99, 99, 99,99, 99, 99, 99, 99, 99, 99, 99,99, 99, 99, 99, 99, 99, 99, 99,99, 99, 99, 99, 99, 99, 99, 99,99, 99, 99, 99, 99, 99, 99, 99,99, 99, 99, 99, 99, 99, 99, 99,99, 99, 99, 99, 99, 99, 99, 99,99, 99, 99, 99, 99, 99, 99, 99,99, 99, 99, 99, 99, 99, 99, 99,99, 99, 99, 99, 99, 99, 99, 99
};static const char kWebSafeBase64DecodeChars[] = {// This array was generated by the following code:// #include <sys/time.h>// #include <stdlib.h>// #include <string.h>// main()// {// static const char Base64[] =// "ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz0123456789-_";// char *pos;// int idx, i, j;// printf(" ");// for (i = 0; i < 255; i += 8) {// for (j = i; j < i + 8; j++) {// pos = strchr(Base64, j);// if ((pos == NULL) || (j == 0))// idx = 99;// else// idx = pos - Base64;// if (idx == 99)// printf(" %2d, ", idx);// else// printf(" %2d/*%c*/,", idx, j);// }// printf("\n ");// }// }99, 99, 99, 99, 99, 99, 99, 99,99, 99, 99, 99, 99, 99, 99, 99,99, 99, 99, 99, 99, 99, 99, 99,99, 99, 99, 99, 99, 99, 99, 99,99, 99, 99, 99, 99, 99, 99, 99,99, 99, 99, 99, 99, 62/*-*/, 99, 99,52/*0*/, 53/*1*/, 54/*2*/, 55/*3*/, 56/*4*/, 57/*5*/, 58/*6*/, 59/*7*/,60/*8*/, 61/*9*/, 99, 99, 99, 99, 99, 99,99, 0/*A*/, 1/*B*/, 2/*C*/, 3/*D*/, 4/*E*/, 5/*F*/, 6/*G*/,7/*H*/, 8/*I*/, 9/*J*/, 10/*K*/, 11/*L*/, 12/*M*/, 13/*N*/, 14/*O*/,15/*P*/, 16/*Q*/, 17/*R*/, 18/*S*/, 19/*T*/, 20/*U*/, 21/*V*/, 22/*W*/,23/*X*/, 24/*Y*/, 25/*Z*/, 99, 99, 99, 99, 63/*_*/,99, 26/*a*/, 27/*b*/, 28/*c*/, 29/*d*/, 30/*e*/, 31/*f*/, 32/*g*/,33/*h*/, 34/*i*/, 35/*j*/, 36/*k*/, 37/*l*/, 38/*m*/, 39/*n*/, 40/*o*/,41/*p*/, 42/*q*/, 43/*r*/, 44/*s*/, 45/*t*/, 46/*u*/, 47/*v*/, 48/*w*/,49/*x*/, 50/*y*/, 51/*z*/, 99, 99, 99, 99, 99,99, 99, 99, 99, 99, 99, 99, 99,99, 99, 99, 99, 99, 99, 99, 99,99, 99, 99, 99, 99, 99, 99, 99,99, 99, 99, 99, 99, 99, 99, 99,99, 99, 99, 99, 99, 99, 99, 99,99, 99, 99, 99, 99, 99, 99, 99,99, 99, 99, 99, 99, 99, 99, 99,99, 99, 99, 99, 99, 99, 99, 99,99, 99, 99, 99, 99, 99, 99, 99,99, 99, 99, 99, 99, 99, 99, 99,99, 99, 99, 99, 99, 99, 99, 99,99, 99, 99, 99, 99, 99, 99, 99,99, 99, 99, 99, 99, 99, 99, 99,99, 99, 99, 99, 99, 99, 99, 99,99, 99, 99, 99, 99, 99, 99, 99,99, 99, 99, 99, 99, 99, 99, 99
};// Tests a character to see if it's a whitespace character.
//
// Returns:
// YES if the character is a whitespace character.
// NO if the character is not a whitespace character.
//
GTM_INLINE BOOL IsSpace(unsigned char c) {// we use our own mapping here because we don't want anything w/ locale// support.static BOOL kSpaces[256] = {0, 0, 0, 0, 0, 0, 0, 0, 0, 1, // 0-91, 1, 1, 1, 0, 0, 0, 0, 0, 0, // 10-190, 0, 0, 0, 0, 0, 0, 0, 0, 0, // 20-290, 0, 1, 0, 0, 0, 0, 0, 0, 0, // 30-390, 0, 0, 0, 0, 0, 0, 0, 0, 0, // 40-490, 0, 0, 0, 0, 0, 0, 0, 0, 0, // 50-590, 0, 0, 0, 0, 0, 0, 0, 0, 0, // 60-690, 0, 0, 0, 0, 0, 0, 0, 0, 0, // 70-790, 0, 0, 0, 0, 0, 0, 0, 0, 0, // 80-890, 0, 0, 0, 0, 0, 0, 0, 0, 0, // 90-990, 0, 0, 0, 0, 0, 0, 0, 0, 0, // 100-1090, 0, 0, 0, 0, 0, 0, 0, 0, 0, // 110-1190, 0, 0, 0, 0, 0, 0, 0, 0, 0, // 120-1290, 0, 0, 0, 0, 0, 0, 0, 0, 0, // 130-1390, 0, 0, 0, 0, 0, 0, 0, 0, 0, // 140-1490, 0, 0, 0, 0, 0, 0, 0, 0, 0, // 150-1591, 0, 0, 0, 0, 0, 0, 0, 0, 0, // 160-1690, 0, 0, 0, 0, 0, 0, 0, 0, 0, // 170-1790, 0, 0, 0, 0, 0, 0, 0, 0, 0, // 180-1890, 0, 0, 0, 0, 0, 0, 0, 0, 0, // 190-1990, 0, 0, 0, 0, 0, 0, 0, 0, 0, // 200-2090, 0, 0, 0, 0, 0, 0, 0, 0, 0, // 210-2190, 0, 0, 0, 0, 0, 0, 0, 0, 0, // 220-2290, 0, 0, 0, 0, 0, 0, 0, 0, 0, // 230-2390, 0, 0, 0, 0, 0, 0, 0, 0, 0, // 240-2490, 0, 0, 0, 0, 1, // 250-255};return kSpaces[c];
}// Calculate how long the data will be once it's base64 encoded.
//
// Returns:
// The guessed encoded length for a source length
//
GTM_INLINE NSUInteger CalcEncodedLength(NSUInteger srcLen, BOOL padded) {NSUInteger intermediate_result = 8 * srcLen + 5;NSUInteger len = intermediate_result / 6;if (padded) {len = ((len + 3) / 4) * 4;}return len;
}// Tries to calculate how long the data will be once it's base64 decoded.
// Unlike the above, this is always an upperbound, since the source data
// could have spaces and might end with the padding characters on them.
//
// Returns:
// The guessed decoded length for a source length
//
GTM_INLINE NSUInteger GuessDecodedLength(NSUInteger srcLen) {return (srcLen + 3) / 4 * 3;
}@interface GTMBase64 (PrivateMethods)+(NSData *)baseEncode:(const void *)byteslength:(NSUInteger)lengthcharset:(const char *)charsetpadded:(BOOL)padded;+(NSData *)baseDecode:(const void *)byteslength:(NSUInteger)lengthcharset:(const char*)charsetrequirePadding:(BOOL)requirePadding;+(NSUInteger)baseEncode:(const char *)srcBytessrcLen:(NSUInteger)srcLendestBytes:(char *)destBytesdestLen:(NSUInteger)destLencharset:(const char *)charsetpadded:(BOOL)padded;+(NSUInteger)baseDecode:(const char *)srcBytessrcLen:(NSUInteger)srcLendestBytes:(char *)destBytesdestLen:(NSUInteger)destLencharset:(const char *)charsetrequirePadding:(BOOL)requirePadding;@end@implementation GTMBase64//
// Standard Base64 (RFC) handling
//+(NSData *)encodeData:(NSData *)data {return [self baseEncode:[data bytes]length:[data length]charset:kBase64EncodeCharspadded:YES];
}+(NSData *)decodeData:(NSData *)data {return [self baseDecode:[data bytes]length:[data length]charset:kBase64DecodeCharsrequirePadding:YES];
}+(NSData *)encodeBytes:(const void *)bytes length:(NSUInteger)length {return [self baseEncode:byteslength:lengthcharset:kBase64EncodeCharspadded:YES];
}+(NSData *)decodeBytes:(const void *)bytes length:(NSUInteger)length {return [self baseDecode:byteslength:lengthcharset:kBase64DecodeCharsrequirePadding:YES];
}+(NSString *)stringByEncodingData:(NSData *)data {NSString *result = nil;NSData *converted = [self baseEncode:[data bytes]length:[data length]charset:kBase64EncodeCharspadded:YES];if (converted) {result = [[[NSString alloc] initWithData:convertedencoding:NSASCIIStringEncoding] autorelease];}return result;
}+(NSString *)stringByEncodingBytes:(const void *)bytes length:(NSUInteger)length {NSString *result = nil;NSData *converted = [self baseEncode:byteslength:lengthcharset:kBase64EncodeCharspadded:YES];if (converted) {result = [[[NSString alloc] initWithData:convertedencoding:NSASCIIStringEncoding] autorelease];}return result;
}+(NSData *)decodeString:(NSString *)string {NSData *result = nil;NSData *data = [string dataUsingEncoding:NSASCIIStringEncoding];if (data) {result = [self baseDecode:[data bytes]length:[data length]charset:kBase64DecodeCharsrequirePadding:YES];}return result;
}//
// Modified Base64 encoding so the results can go onto urls.
//
// The changes are in the characters generated and also the result isn't
// padded to a multiple of 4.
// Must use the matching call to encode/decode, won't interop with the
// RFC versions.
//+(NSData *)webSafeEncodeData:(NSData *)datapadded:(BOOL)padded {return [self baseEncode:[data bytes]length:[data length]charset:kWebSafeBase64EncodeCharspadded:padded];
}+(NSData *)webSafeDecodeData:(NSData *)data {return [self baseDecode:[data bytes]length:[data length]charset:kWebSafeBase64DecodeCharsrequirePadding:NO];
}+(NSData *)webSafeEncodeBytes:(const void *)byteslength:(NSUInteger)lengthpadded:(BOOL)padded {return [self baseEncode:byteslength:lengthcharset:kWebSafeBase64EncodeCharspadded:padded];
}+(NSData *)webSafeDecodeBytes:(const void *)bytes length:(NSUInteger)length {return [self baseDecode:byteslength:lengthcharset:kWebSafeBase64DecodeCharsrequirePadding:NO];
}+(NSString *)stringByWebSafeEncodingData:(NSData *)datapadded:(BOOL)padded {NSString *result = nil;NSData *converted = [self baseEncode:[data bytes]length:[data length]charset:kWebSafeBase64EncodeCharspadded:padded];if (converted) {result = [[[NSString alloc] initWithData:convertedencoding:NSASCIIStringEncoding] autorelease];}return result;
}+(NSString *)stringByWebSafeEncodingBytes:(const void *)byteslength:(NSUInteger)lengthpadded:(BOOL)padded {NSString *result = nil;NSData *converted = [self baseEncode:byteslength:lengthcharset:kWebSafeBase64EncodeCharspadded:padded];if (converted) {result = [[[NSString alloc] initWithData:convertedencoding:NSASCIIStringEncoding] autorelease];}return result;
}+(NSData *)webSafeDecodeString:(NSString *)string {NSData *result = nil;NSData *data = [string dataUsingEncoding:NSASCIIStringEncoding];if (data) {result = [self baseDecode:[data bytes]length:[data length]charset:kWebSafeBase64DecodeCharsrequirePadding:NO];}return result;
}@end@implementation GTMBase64 (PrivateMethods)//
// baseEncode:length:charset:padded:
//
// Does the common lifting of creating the dest NSData. it creates & sizes the
// data for the results. |charset| is the characters to use for the encoding
// of the data. |padding| controls if the encoded data should be padded to a
// multiple of 4.
//
// Returns:
// an autorelease NSData with the encoded data, nil if any error.
//
+(NSData *)baseEncode:(const void *)byteslength:(NSUInteger)lengthcharset:(const char *)charsetpadded:(BOOL)padded {// how big could it be?NSUInteger maxLength = CalcEncodedLength(length, padded);// make spaceNSMutableData *result = [NSMutableData data];[result setLength:maxLength];// do itNSUInteger finalLength = [self baseEncode:bytessrcLen:lengthdestBytes:[result mutableBytes]destLen:[result length]charset:charsetpadded:padded];if (finalLength) {_GTMDevAssert(finalLength == maxLength, @"how did we calc the length wrong?");} else {// shouldn't happen, this means we ran out of spaceresult = nil;}return result;
}//
// baseDecode:length:charset:requirePadding:
//
// Does the common lifting of creating the dest NSData. it creates & sizes the
// data for the results. |charset| is the characters to use for the decoding
// of the data.
//
// Returns:
// an autorelease NSData with the decoded data, nil if any error.
//
//
+(NSData *)baseDecode:(const void *)byteslength:(NSUInteger)lengthcharset:(const char *)charsetrequirePadding:(BOOL)requirePadding {// could try to calculate what it will end up asNSUInteger maxLength = GuessDecodedLength(length);// make spaceNSMutableData *result = [NSMutableData data];[result setLength:maxLength];// do itNSUInteger finalLength = [self baseDecode:bytessrcLen:lengthdestBytes:[result mutableBytes]destLen:[result length]charset:charsetrequirePadding:requirePadding];if (finalLength) {if (finalLength != maxLength) {// resize down to how big it was[result setLength:finalLength];}} else {// either an error in the args, or we ran out of spaceresult = nil;}return result;
}//
// baseEncode:srcLen:destBytes:destLen:charset:padded:
//
// Encodes the buffer into the larger. returns the length of the encoded
// data, or zero for an error.
// |charset| is the characters to use for the encoding
// |padded| tells if the result should be padded to a multiple of 4.
//
// Returns:
// the length of the encoded data. zero if any error.
//
+(NSUInteger)baseEncode:(const char *)srcBytessrcLen:(NSUInteger)srcLendestBytes:(char *)destBytesdestLen:(NSUInteger)destLencharset:(const char *)charsetpadded:(BOOL)padded {if (!srcLen || !destLen || !srcBytes || !destBytes) {return 0;}char *curDest = destBytes;const unsigned char *curSrc = (const unsigned char *)(srcBytes);// Three bytes of data encodes to four characters of cyphertext.// So we can pump through three-byte chunks atomically.while (srcLen > 2) {// space?_GTMDevAssert(destLen >= 4, @"our calc for encoded length was wrong");curDest[0] = charset[curSrc[0] >> 2];curDest[1] = charset[((curSrc[0] & 0x03) << 4) + (curSrc[1] >> 4)];curDest[2] = charset[((curSrc[1] & 0x0f) << 2) + (curSrc[2] >> 6)];curDest[3] = charset[curSrc[2] & 0x3f];curDest += 4;curSrc += 3;srcLen -= 3;destLen -= 4;}// now deal with the tail (<=2 bytes)switch (srcLen) {case 0:// Nothing left; nothing more to do.break;case 1:// One byte left: this encodes to two characters, and (optionally)// two pad characters to round out the four-character cypherblock._GTMDevAssert(destLen >= 2, @"our calc for encoded length was wrong");curDest[0] = charset[curSrc[0] >> 2];curDest[1] = charset[(curSrc[0] & 0x03) << 4];curDest += 2;destLen -= 2;if (padded) {_GTMDevAssert(destLen >= 2, @"our calc for encoded length was wrong");curDest[0] = kBase64PaddingChar;curDest[1] = kBase64PaddingChar;curDest += 2;}break;case 2:// Two bytes left: this encodes to three characters, and (optionally)// one pad character to round out the four-character cypherblock._GTMDevAssert(destLen >= 3, @"our calc for encoded length was wrong");curDest[0] = charset[curSrc[0] >> 2];curDest[1] = charset[((curSrc[0] & 0x03) << 4) + (curSrc[1] >> 4)];curDest[2] = charset[(curSrc[1] & 0x0f) << 2];curDest += 3;destLen -= 3;if (padded) {_GTMDevAssert(destLen >= 1, @"our calc for encoded length was wrong");curDest[0] = kBase64PaddingChar;curDest += 1;}break;}// return the lengthreturn (curDest - destBytes);
}//
// baseDecode:srcLen:destBytes:destLen:charset:requirePadding:
//
// Decodes the buffer into the larger. returns the length of the decoded
// data, or zero for an error.
// |charset| is the character decoding buffer to use
//
// Returns:
// the length of the encoded data. zero if any error.
//
+(NSUInteger)baseDecode:(const char *)srcBytessrcLen:(NSUInteger)srcLendestBytes:(char *)destBytesdestLen:(NSUInteger)destLencharset:(const char *)charsetrequirePadding:(BOOL)requirePadding {if (!srcLen || !destLen || !srcBytes || !destBytes) {return 0;}int decode;NSUInteger destIndex = 0;int state = 0;char ch = 0;while (srcLen-- && (ch = *srcBytes++) != 0) {if (IsSpace(ch)) // Skip whitespacecontinue;if (ch == kBase64PaddingChar)break;decode = charset[(unsigned int)ch];if (decode == kBase64InvalidChar)return 0;// Four cyphertext characters decode to three bytes.// Therefore we can be in one of four states.switch (state) {case 0:// We're at the beginning of a four-character cyphertext block.// This sets the high six bits of the first byte of the// plaintext block._GTMDevAssert(destIndex < destLen, @"our calc for decoded length was wrong");destBytes[destIndex] = decode << 2;state = 1;break;case 1:// We're one character into a four-character cyphertext block.// This sets the low two bits of the first plaintext byte,// and the high four bits of the second plaintext byte._GTMDevAssert((destIndex+1) < destLen, @"our calc for decoded length was wrong");destBytes[destIndex] |= decode >> 4;destBytes[destIndex+1] = (decode & 0x0f) << 4;destIndex++;state = 2;break;case 2:// We're two characters into a four-character cyphertext block.// This sets the low four bits of the second plaintext// byte, and the high two bits of the third plaintext byte.// However, if this is the end of data, and those two// bits are zero, it could be that those two bits are// leftovers from the encoding of data that had a length// of two mod three._GTMDevAssert((destIndex+1) < destLen, @"our calc for decoded length was wrong");destBytes[destIndex] |= decode >> 2;destBytes[destIndex+1] = (decode & 0x03) << 6;destIndex++;state = 3;break;case 3:// We're at the last character of a four-character cyphertext block.// This sets the low six bits of the third plaintext byte._GTMDevAssert(destIndex < destLen, @"our calc for decoded length was wrong");destBytes[destIndex] |= decode;destIndex++;state = 0;break;}}// We are done decoding Base-64 chars. Let's see if we ended// on a byte boundary, and/or with erroneous trailing characters.if (ch == kBase64PaddingChar) { // We got a pad charif ((state == 0) || (state == 1)) {return 0; // Invalid '=' in first or second position}if (srcLen == 0) {if (state == 2) { // We run out of input but we still need another '='return 0;}// Otherwise, we are in state 3 and only need this '='} else {if (state == 2) { // need another '='while ((ch = *srcBytes++) && (srcLen-- > 0)) {if (!IsSpace(ch))break;}if (ch != kBase64PaddingChar) {return 0;}}// state = 1 or 2, check if all remain padding is spacewhile ((ch = *srcBytes++) && (srcLen-- > 0)) {if (!IsSpace(ch)) {return 0;}}}} else {// We ended by seeing the end of the string.if (requirePadding) {// If we require padding, then anything but state 0 is an error.if (state != 0) {return 0;}} else {// Make sure we have no partial bytes lying around. Note that we do not// require trailing '=', so states 2 and 3 are okay too.if (state == 1) {return 0;}}}// If then next piece of output was valid and got written to it means we got a// very carefully crafted input that appeared valid but contains some trailing// bits past the real length, so just toss the thing.if ((destIndex < destLen) &&(destBytes[destIndex] != 0)) {return 0;}return destIndex;
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