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随即生成一个md5的字符串

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  • iOS
 
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首先需要导入两个文件:OpenUDID.h  ,OpenUDID.m

OpenUDID.h:

//

//  OpenUDID.h

//  openudid

//

//  initiated by Yann Lechelle (cofounder @Appsfire) on 8/28/11.

//  Copyright 2011 OpenUDID.org

//

//  Main branches

//      iOS code: https://github.com/ylechelle/OpenUDID

//

 

/*

    !!! IMPORTANT !!!

 

    IF YOU ARE GOING TO INTEGRATE OpenUDID INSIDE A (STATIC) LIBRARY,

    PLEASE MAKE SURE YOU REFACTOR THE OpenUDID CLASS WITH A PREFIX OF YOUR OWN,

    E.G. ACME_OpenUDID. THIS WILL AVOID CONFUSION BY DEVELOPERS WHO ARE ALSO

    USING OpenUDID IN THEIR OWN CODE. 

 

    !!! IMPORTANT !!!

 

*/

 

/*

 http://en.wikipedia.org/wiki/Zlib_License

 

 This software is provided 'as-is', without any express or implied

 warranty. In no event will the authors be held liable for any damages

 arising from the use of this software.

 

 Permission is granted to anyone to use this software for any purpose,

 including commercial applications, and to alter it and redistribute it

 freely, subject to the following restrictions:

 

 1. The origin of this software must not be misrepresented; you must not

 claim that you wrote the original software. If you use this software

 in a product, an acknowledgment in the product documentation would be

 appreciated but is not required.

 

 2. Altered source versions must be plainly marked as such, and must not be

 misrepresented as being the original software.

 

 3. This notice may not be removed or altered from any source

 distribution.

*/

 

#import <Foundation/Foundation.h>

 

//

// Usage:

//    #include "OpenUDID.h"

//    NSString* openUDID = [OpenUDID value];

//

 

#define kOpenUDIDErrorNone          0

#define kOpenUDIDErrorOptedOut      1

#define kOpenUDIDErrorCompromised   2

 

@interface OpenUDID : NSObject {

}

+ (NSString*) value;

+ (NSString*) valueWithError:(NSError**)error;

+ (void) setOptOut:(BOOL)optOutValue;

 

@end



OpenUDID.m


//

//  OpenUDID.m

//  openudid

//

//  initiated by Yann Lechelle (cofounder @Appsfire) on 8/28/11.

//  Copyright 2011 OpenUDID.org

//

//  Initiators/root branches

//      iOS code: https://github.com/ylechelle/OpenUDID

//      Android code: https://github.com/vieux/OpenUDID

//

//  Contributors:

//      https://github.com/ylechelle/OpenUDID/contributors

//

 

/*

 http://en.wikipedia.org/wiki/Zlib_License

 

 This software is provided 'as-is', without any express or implied

 warranty. In no event will the authors be held liable for any damages

 arising from the use of this software.

 

 Permission is granted to anyone to use this software for any purpose,

 including commercial applications, and to alter it and redistribute it

 freely, subject to the following restrictions:

 

 1. The origin of this software must not be misrepresented; you must not

 claim that you wrote the original software. If you use this software

 in a product, an acknowledgment in the product documentation would be

 appreciated but is not required.

 

 2. Altered source versions must be plainly marked as such, and must not be

 misrepresented as being the original software.

 

 3. This notice may not be removed or altered from any source

 distribution.

*/

 

#if __has_feature(objc_arc)

#error This file uses the classic non-ARC retain/release model; hints below... 

    // to selectively compile this file as non-ARC, do as follows:

    // https://img.skitch.com/20120411-bcku69k1uw528cwh9frh5px8ya.png

#endif

 

#import "OpenUDID.h"

#import <CommonCrypto/CommonDigest.h> // Need to import for CC_MD5 access

#if TARGET_OS_IPHONE || TARGET_IPHONE_SIMULATOR

#import <UIKit/UIPasteboard.h>

#import <UIKit/UIKit.h>

#else

#import <AppKit/NSPasteboard.h>

#endif

 

#define OpenUDIDLog(fmt, ...)

//#define OpenUDIDLog(fmt, ...) //NSLog((@"%s [Line %d] " fmt), __PRETTY_FUNCTION__, __LINE__, ##__VA_ARGS__);

//#define OpenUDIDLog(fmt, ...) //NSLog((@"[Line %d] " fmt), __LINE__, ##__VA_ARGS__);

 

static NSString * kOpenUDIDSessionCache = nil;

static NSString * const kOpenUDIDKey = @"OpenUDID";

static NSString * const kOpenUDIDSlotKey = @"OpenUDID_slot";

static NSString * const kOpenUDIDAppUIDKey = @"OpenUDID_appUID";

static NSString * const kOpenUDIDTSKey = @"OpenUDID_createdTS";

static NSString * const kOpenUDIDOOTSKey = @"OpenUDID_optOutTS";

static NSString * const kOpenUDIDDomain = @"org.OpenUDID";

static NSString * const kOpenUDIDSlotPBPrefix = @"org.OpenUDID.slot.";

static int const kOpenUDIDRedundancySlots = 100;

 

@interface OpenUDID (Private)

+ (void) _setDict:(id)dict forPasteboard:(id)pboard;

+ (NSMutableDictionary*) _getDictFromPasteboard:(id)pboard;

+ (NSString*) _generateFreshOpenUDID;

@end

 

@implementation OpenUDID

 

// Archive a NSDictionary inside a pasteboard of a given type

// Convenience method to support iOS & Mac OS X

//

+ (void) _setDict:(id)dict forPasteboard:(id)pboard {

#if TARGET_OS_IPHONE || TARGET_IPHONE_SIMULATOR

    [pboard setData:[NSKeyedArchiver archivedDataWithRootObject:dict] forPasteboardType:kOpenUDIDDomain];

#else

    [pboard setData:[NSKeyedArchiver archivedDataWithRootObject:dict] forType:kOpenUDIDDomain];

#endif

}

 

// Retrieve an NSDictionary from a pasteboard of a given type

// Convenience method to support iOS & Mac OS X

//

+ (NSMutableDictionary*) _getDictFromPasteboard:(id)pboard {

#if TARGET_OS_IPHONE || TARGET_IPHONE_SIMULATOR

    id item = [pboard dataForPasteboardType:kOpenUDIDDomain];

#else

id item = [pboard dataForType:kOpenUDIDDomain];

#endif

    if (item) {

        @try{

            item = [NSKeyedUnarchiver unarchiveObjectWithData:item];

        } @catch(NSException* e) {

            OpenUDIDLog(@"Unable to unarchive item %@ on pasteboard!", [pboard name]);

            item = nil;

        }

    }

 

    // return an instance of a MutableDictionary 

    return [NSMutableDictionary dictionaryWithDictionary:(item == nil || [item isKindOfClass:[NSDictionary class]]) ? item : nil];

}

 

// Private method to create and return a new OpenUDID

// Theoretically, this function is called once ever per application when calling [OpenUDID value] for the first time.

// After that, the caching/pasteboard/redundancy mechanism inside [OpenUDID value] returns a persistent and cross application OpenUDID

//

+ (NSString*) _generateFreshOpenUDID {

 

    NSString* _openUDID = nil;

 

    // August 2011: One day, this may no longer be allowed in iOS. When that is, just comment this line out.

    // March 25th 2012: this day has come, let's remove this "outlawed" call... 

#if TARGET_OS_IPHONE

//    if([UIDevice instancesRespondToSelector:@selector(uniqueIdentifier)]){

//        _openUDID = [[UIDevice currentDevice] uniqueIdentifier];

//    }

#endif

    // Next we generate a UUID.

    // UUIDs (Universally Unique Identifiers), also known as GUIDs (Globally Unique Identifiers) or IIDs 

    // (Interface Identifiers), are 128-bit values guaranteed to be unique. A UUID is made unique over 

    // both space and time by combining a value unique to the computer on which it was generated—usually the

    // Ethernet hardware address—and a value representing the number of 100-nanosecond intervals since 

    // October 15, 1582 at 00:00:00.

    // We then hash this UUID with md5 to get 32 bytes, and then add 4 extra random bytes

    // Collision is possible of course, but unlikely and suitable for most industry needs (e.g. aggregate tracking)

    //

    if (_openUDID==nil) {

        CFUUIDRef uuid = CFUUIDCreate(kCFAllocatorDefault);

        CFStringRef cfstring = CFUUIDCreateString(kCFAllocatorDefault, uuid);

        const char *cStr = CFStringGetCStringPtr(cfstring,CFStringGetFastestEncoding(cfstring));

        unsigned char result[16];

        CC_MD5( cStr, strlen(cStr), result );

        CFRelease(uuid);

 

        _openUDID = [NSString stringWithFormat:

                @"%02x%02x%02x%02x%02x%02x%02x%02x%02x%02x%02x%02x%02x%02x%02x%02x%08llx",

                result[0], result[1], result[2], result[3], 

                result[4], result[5], result[6], result[7],

                result[8], result[9], result[10], result[11],

                result[12], result[13], result[14], result[15],

                arc4random() % 4294967295];  

    }

 

    // Call to other developers in the Open Source community:

    //

    // feel free to suggest better or alternative "UDID" generation code above.

    // NOTE that the goal is NOT to find a better hash method, but rather, find a decentralized (i.e. not web-based)

    // 160 bits / 20 bytes random string generator with the fewest possible collisions.

    // 

 

    return _openUDID;

}

 

 

// Main public method that returns the OpenUDID

// This method will generate and store the OpenUDID if it doesn't exist, typically the first time it is called

// It will return the null udid (forty zeros) if the user has somehow opted this app out (this is subject to 3rd party implementation)

// Otherwise, it will register the current app and return the OpenUDID

//

+ (NSString*) value {

    return [OpenUDID valueWithError:nil];

}

 

+ (NSString*) valueWithError:(NSError **)error {

 

    if (kOpenUDIDSessionCache!=nil) {

        if (error!=nil)

            *error = [NSError errorWithDomain:kOpenUDIDDomain

                                         code:kOpenUDIDErrorNone

                                     userInfo:[NSDictionary dictionaryWithObjectsAndKeys:@"OpenUDID in cache from first call",@"description", nil]];

        return kOpenUDIDSessionCache;

    }

 

  NSUserDefaults *defaults = [NSUserDefaults standardUserDefaults];

 

    // The AppUID will uniquely identify this app within the pastebins

    //

    NSString * appUID = (NSString *) [defaults objectForKey:kOpenUDIDAppUIDKey];

    if(appUID == nil)

    {

      // generate a new uuid and store it in user defaults

      CFUUIDRef uuid = CFUUIDCreate(NULL);

      appUID = (NSString *) CFUUIDCreateString(NULL, uuid);

      CFRelease(uuid);

    }

 

    NSString* openUDID = nil;

    NSString* myRedundancySlotPBid = nil;

    NSDate* optedOutDate = nil;

    BOOL optedOut = NO;

    BOOL saveLocalDictToDefaults = NO;

    BOOL isCompromised = NO;

 

    // Do we have a local copy of the OpenUDID dictionary?

    // This local copy contains a copy of the openUDID, myRedundancySlotPBid (and unused in this block, the local bundleid, and the timestamp)

    //

    id localDict = [defaults objectForKey:kOpenUDIDKey];

    if ([localDict isKindOfClass:[NSDictionary class]]) {

        localDict = [NSMutableDictionary dictionaryWithDictionary:localDict]; // we might need to set/overwrite the redundancy slot

        openUDID = [localDict objectForKey:kOpenUDIDKey];

        myRedundancySlotPBid = [localDict objectForKey:kOpenUDIDSlotKey];

        optedOutDate = [localDict objectForKey:kOpenUDIDOOTSKey];

        optedOut = optedOutDate!=nil;

        OpenUDIDLog(@"localDict = %@",localDict);

    }

 

    // Here we go through a sequence of slots, each of which being a UIPasteboard created by each participating app

    // The idea behind this is to both multiple and redundant representations of OpenUDIDs, as well as serve as placeholder for potential opt-out

    //

    NSString* availableSlotPBid = nil;

    NSMutableDictionary* frequencyDict = [NSMutableDictionary dictionaryWithCapacity:kOpenUDIDRedundancySlots];

    for (int n=0; n<kOpenUDIDRedundancySlots; n++) {

        NSString* slotPBid = [NSString stringWithFormat:@"%@%d",kOpenUDIDSlotPBPrefix,n];

#if TARGET_OS_IPHONE || TARGET_IPHONE_SIMULATOR

        UIPasteboard* slotPB = [UIPasteboard pasteboardWithName:slotPBid create:NO];

#else

        NSPasteboard* slotPB = [NSPasteboard pasteboardWithName:slotPBid];

#endif

        OpenUDIDLog(@"SlotPB name = %@",slotPBid);

        if (slotPB==nil) {

            // assign availableSlotPBid to be the first one available

            if (availableSlotPBid==nil) availableSlotPBid = slotPBid;

        } else {

            NSDictionary* dict = [OpenUDID _getDictFromPasteboard:slotPB];

            NSString* oudid = [dict objectForKey:kOpenUDIDKey];

            OpenUDIDLog(@"SlotPB dict = %@",dict);

            if (oudid==nil) {

                // availableSlotPBid could inside a non null slot where no oudid can be found

                if (availableSlotPBid==nil) availableSlotPBid = slotPBid;

            } else {

                // increment the frequency of this oudid key

                int count = [[frequencyDict valueForKey:oudid] intValue];

                [frequencyDict setObject:[NSNumber numberWithInt:++count] forKey:oudid];

            }

            // if we have a match with the app unique id,

            // then let's look if the external UIPasteboard representation marks this app as OptedOut

            NSString* gid = [dict objectForKey:kOpenUDIDAppUIDKey];

            if (gid!=nil && [gid isEqualToString:appUID]) {

                myRedundancySlotPBid = slotPBid;

                // the local dictionary is prime on the opt-out subject, so ignore if already opted-out locally

                if (optedOut) {

                    optedOutDate = [dict objectForKey:kOpenUDIDOOTSKey];

                    optedOut = optedOutDate!=nil;   

                }

            }

        }

    }

 

    // sort the Frequency dict with highest occurence count of the same OpenUDID (redundancy, failsafe)

    // highest is last in the list

    //

    NSArray* arrayOfUDIDs = [frequencyDict keysSortedByValueUsingSelector:@selector(compare:)];

    NSString* mostReliableOpenUDID = (arrayOfUDIDs!=nil && [arrayOfUDIDs count]>0)? [arrayOfUDIDs lastObject] : nil;

    OpenUDIDLog(@"Freq Dict = %@\nMost reliable %@",frequencyDict,mostReliableOpenUDID);

 

    // if openUDID was not retrieved from the local preferences, then let's try to get it from the frequency dictionary above

    //

    if (openUDID==nil) {        

        if (mostReliableOpenUDID==nil) {

            // this is the case where this app instance is likely to be the first one to use OpenUDID on this device

            // we create the OpenUDID, legacy or semi-random (i.e. most certainly unique)

            //

            openUDID = [OpenUDID _generateFreshOpenUDID];

        } else {

            // or we leverage the OpenUDID shared by other apps that have already gone through the process

            // 

            openUDID = mostReliableOpenUDID;

        }

        // then we create a local representation

        //

        if (localDict==nil) { 

            localDict = [NSMutableDictionary dictionaryWithCapacity:4];

            [localDict setObject:openUDID forKey:kOpenUDIDKey];

            [localDict setObject:appUID forKey:kOpenUDIDAppUIDKey];

            [localDict setObject:[NSDate date] forKey:kOpenUDIDTSKey];

            if (optedOut) [localDict setObject:optedOutDate forKey:kOpenUDIDTSKey];

            saveLocalDictToDefaults = YES;

        }

    }

    else {

        // Sanity/tampering check

        //

        if (mostReliableOpenUDID!=nil && ![mostReliableOpenUDID isEqualToString:openUDID])

            isCompromised = YES;

    }

 

    // Here we store in the available PB slot, if applicable

    //

    OpenUDIDLog(@"Available Slot %@ Existing Slot %@",availableSlotPBid,myRedundancySlotPBid);

    if (availableSlotPBid!=nil && (myRedundancySlotPBid==nil || [availableSlotPBid isEqualToString:myRedundancySlotPBid])) {

#if TARGET_OS_IPHONE || TARGET_IPHONE_SIMULATOR

        UIPasteboard* slotPB = [UIPasteboard pasteboardWithName:availableSlotPBid create:YES];

        [slotPB setPersistent:YES];

#else

        NSPasteboard* slotPB = [NSPasteboard pasteboardWithName:availableSlotPBid];

#endif

 

        // save slotPBid to the defaults, and remember to save later

        //

        if (localDict) {

            [localDict setObject:availableSlotPBid forKey:kOpenUDIDSlotKey];

            saveLocalDictToDefaults = YES;

        }

 

        // Save the local dictionary to the corresponding UIPasteboard slot

        //

        if (openUDID && localDict)

            [OpenUDID _setDict:localDict forPasteboard:slotPB];

    }

 

    // Save the dictionary locally if applicable

    //

    if (localDict && saveLocalDictToDefaults)

        [defaults setObject:localDict forKey:kOpenUDIDKey];

 

    // If the UIPasteboard external representation marks this app as opted-out, then to respect privacy, we return the ZERO OpenUDID, a sequence of 40 zeros...

    // This is a *new* case that developers have to deal with. Unlikely, statistically low, but still.

    // To circumvent this and maintain good tracking (conversion ratios, etc.), developers are invited to calculate how many of their users have opted-out from the full set of users.

    // This ratio will let them extrapolate convertion ratios more accurately.

    //

    if (optedOut) {

        if (error!=nil) *error = [NSError errorWithDomain:kOpenUDIDDomain

                                                     code:kOpenUDIDErrorOptedOut

                                                 userInfo:[NSDictionary dictionaryWithObjectsAndKeys:[NSString stringWithFormat:@"Application with unique id %@ is opted-out from OpenUDID as of %@",appUID,optedOutDate],@"description", nil]];

 

        kOpenUDIDSessionCache = [[NSString stringWithFormat:@"%040x",0] retain];

        return kOpenUDIDSessionCache;

    }

 

    // return the well earned openUDID!

    //

    if (error!=nil) {

        if (isCompromised)

            *error = [NSError errorWithDomain:kOpenUDIDDomain

                                         code:kOpenUDIDErrorCompromised

                                     userInfo:[NSDictionary dictionaryWithObjectsAndKeys:@"Found a discrepancy between stored OpenUDID (reliable) and redundant copies; one of the apps on the device is most likely corrupting the OpenUDID protocol",@"description", nil]];

        else

            *error = [NSError errorWithDomain:kOpenUDIDDomain

                                         code:kOpenUDIDErrorNone

                                     userInfo:[NSDictionary dictionaryWithObjectsAndKeys:@"OpenUDID succesfully retrieved",@"description", nil]];

    }

    kOpenUDIDSessionCache = [openUDID retain];

    return kOpenUDIDSessionCache;

}

 

+ (void) setOptOut:(BOOL)optOutValue {

 

    // init call

    [OpenUDID value];

 

    NSUserDefaults *defaults = [NSUserDefaults standardUserDefaults];

 

    // load the dictionary from local cache or create one

    id dict = [defaults objectForKey:kOpenUDIDKey];

    if ([dict isKindOfClass:[NSDictionary class]]) 

    {

        dict = [NSMutableDictionary dictionaryWithDictionary:dict];

    } else {

        dict = [NSMutableDictionary dictionaryWithCapacity:2];

    }

 

    // set the opt-out date or remove key, according to parameter

    if (optOutValue)

        [dict setObject:[NSDate date] forKey:kOpenUDIDOOTSKey];

    else

        [dict removeObjectForKey:kOpenUDIDOOTSKey];

 

  // store the dictionary locally

    [defaults setObject:dict forKey:kOpenUDIDKey];

 

    OpenUDIDLog(@"Local dict after opt-out = %@",dict);

 

    // reset memory cache 

    kOpenUDIDSessionCache = nil;

 

}

 

@end




 

 

 

 

 

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    vb-字符串md5码生成器

    在VB(Visual Basic)环境中,开发一个MD5码生成器可以帮助用户快速计算字符串的MD5值,这对于数据校验、密码存储或文件完整性检查等场景非常有用。 MD5的工作原理基于密码学中的散列函数概念,它将输入数据通过一...

    MD5加密字符串(32位,16位大小写输出)

    MD5(Message-Digest Algorithm 5)是一种广泛使用的哈希函数,设计用于生成一个128位(16字节)的散列值,通常表示为32位的十六进制数字,也就是32个字符的字符串。这个过程被称为MD5哈希或MD5校验和,它在信息技术...

    md5算法.可以对文件和字符串计算md5值

    你可以创建一个MD5_CTX对象,调用`MD5_Init`开始计算,然后用`MD5_Update`处理文件或字符串内容,最后调用`MD5_Final`获取MD5值。如果是在处理文件,你需要逐块读取文件内容,每次调用`MD5_Update`。计算完成后,...

    MD5加密 32位加密字符串

    MD5加密 32位加密字符串 MD5加密 32位加密字符串 MD5加密 32位加密字符串

    MD5字符串工具.7z

    总的来说,这款“MD5字符串工具”是一个基于Lazarus或Delphi开发的实用小工具,旨在帮助用户快速地对字符串进行MD5加密,适用于教学、测试或者验证数据一致性。由于提供了源代码,对于想要深入理解MD5算法以及Pascal...

    MD5包直接生成MD5加密字符串

    经常把用户密码经过MD5加密之后保存到数据库,弄成个包以便备用。放到lib下直接导入调用就行了。。。 &lt;br&gt;//////// import com.sinnk.Md5; ... System.out.println(Md5.getMD5(\"加密之前的密码\"));...

    字符串、文件MD5值计算工具

    标题中的“字符串、文件MD5值计算工具”指的是一个程序,能够快速计算出字符串和文件的MD5哈希值。这个工具简化了MD5计算的过程,用户只需输入字符串或者直接将文件拖拽到程序界面上,程序就能自动计算出对应的MD5值...

    生成随机字符串(字符串,数字)

    例如,生成一个由小写字母组成的字符串: ```csharp string alphabet = "abcdefghijklmnopqrstuvwxyz"; int length = 10; StringBuilder sb = new StringBuilder(); Random rand = new Random(); for (int i = 0; i...

    .NET中获取字符串的MD5码

    MD5是一种不可逆的散列函数,其主要功能是接收输入(通常是字符串)并生成一个固定长度的输出(散列值)。这个输出通常是一个32位的十六进制数,每个字符代表4位的二进制数。由于其不可逆性,即使知道散列值也无法...

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