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Shlok Kumar
Shlok Kumar

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SHA256 in Solidity

SHA256 in Solidity provides developers with a secure and efficient way to perform cryptographic operations on their data

SHA256 is a cryptographic hashing algorithm used in Solidity, the programming language of Ethereum. SHA stands for Secure Hash Algorithm and it was developed by the National Security Agency (NSA) to ensure data integrity when transferring information over a network. It produces an output called a hash value which is unique to each input, making it almost impossible to reverse engineer or generate two inputs that produce identical outputs. This makes SHA256 ideal for use in blockchain applications such as smart contracts, where data must be stored securely and tamper-proofed against malicious actors.

Solidity provides the sha256() function that computes the SHA-256 hash of the input and returns a bytes32 value. The sha256() function is used for hashing in Solidity, which is a process of converting an input (message) of arbitrary length into a fixed-size output (hash value) using a mathematical algorithm. The hash value is unique to the input message, and any change in the input message will result in a different hash value. The sha256() function is widely used in Solidity for its simplicity and efficiency.

The sha256() function outputs a fixed-size byte array, which can be easily accessed to obtain the leading byte of the hash. For example, if we use sha256("Hello World2"), we get 0x0de69f56365c10550d05e65ae8229dd0686f7894a807830daec8caa879731f4d as output. To find out the leading byte from this output, we can simply access bytes32, which gives us 0x0d.

Solidity provides the sha256() function to compute the SHA-256 hash of a given input. The sha256() function takes a bytes type argument and returns a bytes32 type output. Here's an example Solidity contract that demonstrates the use of sha256():

// SPDX-License-Identifier: MIT
pragma solidity ^0.8.0;

contract HashExample {
    function getHash(bytes memory data) public pure returns (bytes32) {
        return sha256(data);
    }
}
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This contract defines a function called getHash() that takes a bytes type argument and returns its SHA-256 hash as a bytes32 type value. The function is marked as pure because it does not modify the state of the contract.

In conclusion, Solidity provides the sha256() function for hashing in smart contracts. It computes the SHA-256 hash of the input and returns a bytes32 value. The output of sha256() can be easily accessed to obtain any byte of the hash value. Hashing is an essential concept in blockchain technology that ensures data integrity and security.

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Top comments (4)

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souadhimel profile image
souadhimel

Excellent write -up. 🔥🔥🔥
Keep going. Wanna more 💖💖

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shlok2740 profile image
Shlok Kumar

Thanks for the comment

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timjohnson2584 profile image
timjohnson2584

Great information, very comprehensive and easy to understand.

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shlok2740 profile image
Shlok Kumar

Thanks for that