Libsodium is a modern, easy-to-use software library for encryption, decryption, signatures, password hashing, and more. It is a portable, cross-platform, installable, and packageable fork of NaCl, with a compatible API and improved security and usability features.

Pros

• High-level cryptographic library with a focus on usability and security
• Cross-platform support (Windows, macOS, Linux, and more)
• Constant-time implementations to mitigate timing attacks
• Active development and maintenance

Cons

• Limited support for older cryptographic algorithms
• Slightly larger binary size compared to some alternatives
• May require additional steps for integration in some development environments
• Learning curve for developers new to modern cryptography concepts

Code Examples

1. Generating a random key:

#include <sodium.h>

unsigned char key[crypto_secretbox_KEYBYTES];
crypto_secretbox_keygen(key);

2. Encrypting a message:

#include <sodium.h>

const unsigned char nonce[crypto_secretbox_NONCEBYTES];
const unsigned char key[crypto_secretbox_KEYBYTES];
const unsigned char *message;
unsigned long long message_len;
unsigned char *ciphertext;

crypto_secretbox_easy(ciphertext, message, message_len, nonce, key);

3. Hashing a password:

#include <sodium.h>

char *passwd = "password123";
unsigned char hashed_password[crypto_pwhash_STRBYTES];

if (crypto_pwhash_str(hashed_password, passwd, strlen(passwd),
                      crypto_pwhash_OPSLIMIT_INTERACTIVE,
                      crypto_pwhash_MEMLIMIT_INTERACTIVE) != 0) {
    /* out of memory */
}

Getting Started

1. Install libsodium:

   • On macOS: brew install libsodium
   • On Ubuntu: sudo apt-get install libsodium-dev
   • On Windows: Download pre-built binaries from the official website

2. Include libsodium in your project:

   • Add #include <sodium.h> to your source files
   • Link against libsodium when compiling (e.g., -lsodium)

3. Initialize libsodium in your code:

#include <sodium.h>

int main(void) {
    if (sodium_init() < 0) {
        /* panic! the library couldn't be initialized */
        return 1;
    }

    /* Your code here */

    return 0;
}