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In PHP, hashing algorithms are an important tool to ensure data integrity and security. PHP provides a variety of hash methods, among which hash_update_stream and openssl_digest() are two commonly used hash functions. However, there are some differences in safety, functionality, performance, etc. between the two. This article will conduct a detailed comparison and analysis of the two to help developers better understand their differences and choose the most appropriate hashing method.
hash_update_stream is one of the built-in hash functions in PHP that can process data streams step by step and hash them. This function is used in conjunction with hash_init() and hash_update() and is suitable for processing big data or streaming data.
$context = hash_init('sha256');
$fp = fopen('largefile.txt', 'rb');
while (!feof($fp)) {
$data = fread($fp, 1024);
hash_update_stream($context, $data);
}
fclose($fp);
$hash = hash_final($context);
echo $hash;
In the above example, hash_update_stream is used to process a large file stream. It reads data block by block and calculates hash values in real time.
openssl_digest() is a function provided in PHP, which uses the encryption algorithm of the OpenSSL library for hash calculation. It not only supports streaming data processing, but also hashing calculations for a single string. This function is usually used for stronger encryption and security requirements, because OpenSSL provides a variety of strong encryption algorithms, such as SHA256, SHA512, etc.
$data = file_get_contents('largefile.txt');
$hash = openssl_digest($data, 'sha256');
echo $hash;
In this example, openssl_digest() directly hashs the file contents. Unlike the step-by-step streaming process of hash_update_stream , openssl_digest() calculates the hash value of the entire data at one time.
hash_update_stream : It relies on the hash extension of PHP, and the supported algorithms include common SHA and MD5. Although these algorithms are sufficient to meet most security needs, some algorithms such as MD5 and SHA-1 have been considered to have security vulnerabilities in recent years and may be threatened by collision attacks.
openssl_digest() : It uses the encryption algorithm provided by OpenSSL to support stronger encryption algorithms, such as SHA-256, SHA-512 and higher-level encryption methods. OpenSSL's encryption library has been audited and updated for many years, so the algorithms it supports are usually highly secure.
hash_update_stream : Although the PHP hash extension library has high performance, it may have known vulnerabilities or does not support some latest security features in some older versions. Over time, some hash algorithms have gradually become considered no longer safe.
openssl_digest() : OpenSSL is a frequently updated encryption library that will promptly fix known security vulnerabilities. In contrast, OpenSSL supports algorithms generally more modern and secure.
Openssl_digest() usually performs better in terms of cryptographic performance, especially when dealing with complex algorithms such as SHA-512, its performance advantages are more obvious. In contrast, hash_update_stream also performs quite well when processing big data streams, but may be slightly inferior in encryption strength because it relies on more basic hash algorithms.
hash_update_stream is specially designed for streaming data, especially suitable for handling large files or real-time data streams. When processing big data, hash_update_stream does not load all data into memory at once, thus avoiding the problem of memory overflow.
openssl_digest() can also process streaming data, but its design prefers to process the entire data set at one time, suitable for scenarios with small data volume or sufficient memory.
openssl_digest() provides a stronger encryption algorithm, and OpenSSL itself is a strictly audited encryption library. Therefore, it is suitable for scenarios where high security is required, especially in financial, government and enterprise-level applications.
hash_update_stream is more suitable for general hashing needs and is suitable for scenarios that do not involve advanced encryption requirements.
In terms of security, openssl_digest() is more powerful than hash_update_stream , especially because it uses more advanced encryption algorithms and relies on OpenSSL, a widely audited encryption library. If your application needs to process high-security data, especially in combating collision attacks, brute-force cracking, etc., it is recommended to use openssl_digest() .
However, if you need to deal with large data streams and memory usage is limited, hash_update_stream is a very practical choice. It can effectively avoid memory overflow and is suitable for use in environments where streaming data processing is required.
In PHP code, if you want to make a URL request, you will usually use a domain name such as https://example.com . If you want to replace the domain name with m66.net , you can do it like this in the code:
