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What are crypto.constants?

Jennifer Isintume

Cybercrime is a criminal activity that uses new technologies against an individual at many levels. These cybercriminals tailor their attacks using some methods and co-operate with each other to achieve their aims. This crime has no bounds and can affect every aspect of an individual’s life. Cyber hackers pose a significant threat as they seek the easiest way to access and clone a database for their advantage. To avoid this, extra steps must be taken to protect user details.

What are crypto.constants in Node.js?

Crypto is a concept derived from cryptographythe process through which codes are converted into data and vice-versa., to allow only the recipient, for whom the data is intended, to read and understand it. The crypto module is in built-in module in Node.js that uses the require method to import it. For example:

Const crypto = require(“crypto”);

Any Node.js built without support for crypto will generate an error at run time. An attempt to require the module using the ES6 import method or the ES5 require method will generate an error, but this error can be resolved using try and catch when using Common.js.

let crypto; 
      try {
  crypto = require(“crypto”)
} catch(err) {
console.log(“crypto support is disabled”)

Crypto constants are one of the methods found in the crypto module. They return an object that contains constants commonly used for security and crypto-related operations. Some commonly used constants are found in the crypto module, which can be seen in the two lines of code below.

Const crypto = require(“crypto”) 

Nodejs crypto constants have two default methods:

  • DefaultCoreCipherList specifies the built-in default cipher list used by Node.js.

  • DefaultCipherList specifies the active default cipher list used by the current Node.js process.

There are many ways that a constant function can be used in crypto. One of the ways uses the syntax below.

static privateDecrypt(key, data) {
    return crypto.privateDecrypt({
      key: key.toPem(),
      padding: crypto.constants.RSA_PKCS1_PADDING,
    }, data);

A few other examples of crypto constants are:

  • Constants for CryptEncodeObject and CryptDecodeObject: These Predefined constants are used with Abstract Syntax Notation One (ASN.1) to encode and decode operations. ASNAbsolute Security Descriptor is a security descriptor structure that contains pointers to the security information associated with an object.

  • Constants for Netscape Extensions: These Predefined constants are used for Netscape certificate extensions. This section provides details on the use of these extensions with ASN.1 encoding and decoding operations.

  • Cryptographic Provider Names (CPN) : CPN predefines string constants for the names of common cryptographic service providersCSP. CSPs identify the certification authorityCA that issues server and client authentication certificates to the servers and clients that request these certificates. Because it contains a public key used in digital signatures, it is also referred to as a Signature Certificate.

  • MAXUIDLEN: MAXUIDLEN is a numeric constant that specifies the maximum number of characters that some Microsoft cryptographic providers will use when obtaining the user ID.



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