md5

php 在做注册、登录或是url 传递参数时都会用到 字符变量的加密，下面我们就来简单的介绍下：php 自带的加密函数 不可逆的加密函数为：md5()、crypt() md5() 用来计算 MD5 哈稀。语法为：string md5(string str); crypt() 将字符串用 UNIX 的标准加密 DES 模块加密。这是单向的加密函数，无法解密。欲比对字符串，将已加密的字符串的头二个字符放在 salt 的参数中，再比对加密后的字符串。语法为：string crypt(string str, string [salt]); 可逆转的加密为：base64_encode()、urlencode() 相对应的解密函数：base64_decode() 、urldecode() base64_encode() 将字符串以 MIME BASE64 编码。此编码方式可以让中文字或者图片也能在网络上顺利传输。语法为string base64_encode(string data); 它的解密函数为：string base64_decode(string encoded_data); 将复回原样 urlencode() 将字符串以 URL 编码。例如空格就会变成加号。语法为：string urlencode(string str); 它的解密函数为：string urldecode

I have a very large table in MySQL. I'm using a CHAR(32) field which contains an MD5 as a string of course. I'm running into an issue where I need to convert this to a decimal value using MySQL. A third party tool runs the query so writing code to do this isn't really an option. MySQL does support storing hex values natively and converting them to integers. But it gets hung up converting it from a string. Here's what I've tried so far (md5_key is the name of my column) First I just tried the UNHEX function but that returns a string so it gave me gooblygoop. I won't put that here. Next I tried

I am trying to build an application that needs to compare the MD5 hash of any file. Due to specific issues, before the upload, the MD5 must be generated client side, and after the upload the application needs to check it server side. My first approach was to use, at the client side, the JavaScript File API and the FileReader.ReadAs functions. Then I use the MD5 algorithm found here: http://pajhome.org.uk/crypt/md5/ Server side, I would use PHP's fopen command and the md5 function. This approach works fine when using simple text files. But, when a binary file is used (like some jpg or pdf), the

I need a 4-character hash. At the moment I am taking the first 4 characters of a md5() hash. I am hashing a string which is 80 characters long or less. Will this lead to collision? or, what is the chance of collision, assuming I'll hash less than 65,536 (16 4 ) different elements? Surprisingly high indeed. As you can see from this graph of an approximate collision probability (formula from the wikipedia page ), with just a few hundred elements your probability of having a collision is over 50%. Note, of course, if you're facing the possibility of an attacker providing the string, you can

I need a function that will take an entire cell value in Excel and convert the value into its MD5 hash equivalent in a new cell. Is there a formula in excel that does that? I need solution without using VBA. Is it possible? Taosique I did this. Here you can download MD5 in pure Excel without VBA. Office 2013 ONLY. https://tzamtzis.gr/2017/web-analytics/excel-function-md5-hashing-without-vba/ https://tzamtzis.gr/tzamtziswp/wp-content/uploads/2017/05/MD5.xlsx Office 2013 comes with handy functions for bitwise operations like BITAND() , BITOR() , BITXOR() , BITR[L]SHIFT() . I think it's

I want to serialize/deserialize md5 context. But I don't know how to do it in Python. Pseudocode of what I want to do. import md5 # Start hash generation m = md5.new() m.update("Content") # Serialize m serialized_m = serialize(m) # In another function/machine, deserialize m # and continue hash generation m2 = deserialize(serialized_m) m2.update("More content") m2.digest() There are C++ libraries for this. Is there one for Python? Why doesn't the md5 library support it? Are there security concerns? Thanks. Edited: I want to do this because for example, an HTTP server wants to accept streaming

I've written a script that reads through all files in a directory and returns md5 hash for each file. However, it renders nothing for a rather large file. I assume that the interpreter has some value set for maximum processing time, and since it takes too long to get this value, it just skips along to other files. Is there anyway to get an md5 checksum for large files through PHP? If not, could it be done through a chron job with cpanel? I gave it a shot there but it doesn't seem that my md5sum command has ever been processed: I never get an email with the hash. Here's the PHP I've already

What would be the fastest and more robust (in terms of uniqueness) way for implementing a method like public abstract String hash(String[] values); The values[] array has 100 to 1,000 members, each of a which with few dozen characters, and the method needs to be run about 10,000 times/sec on a different values[] array each time. Should a long string be build using a StringBuilder buffer and then a hash method invoked on the buffer contents, or is it better to keep invoking the hash method for each string from values[] ? Obviously a hash of at least 64 bits is needed (e.g., MD5) to avoid