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C++ Requires Chilkat v11.6.0+

Hash a Password with Argon2 (Tuned Options)

Demonstrates Crypt2.Argon2HashPassword with explicit options: the cost parameters, saltLen (how many random salt bytes to generate when no salt is given), and an optional secret (pepper).

Background. For hashing, the salt is optional — when omitted, a random salt of saltLen bytes (default 16) is generated, which is the normal case. A secret or ad is not stored in the PHC string; the same values must be supplied to Argon2VerifyPassword for the password to verify.

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C++
#include <CkCrypt2.h>
#include <CkJsonObject.h>

void ChilkatSample(void)
    {
    CkCrypt2 crypt;

    //  The password should come from a secure source rather than being hard-coded.
    const char *password = "correct horse battery staple";

    //  The Argon2 options are the same members as Argon2DeriveKey, except the salt is optional for
    //  hashing.  When no "salt" is given, a random salt is generated; "saltLen" (default 16, range 8..1024)
    //  sets how many random bytes to use.
    CkJsonObject json;
    json.UpdateString("variant","argon2id");
    json.UpdateInt("memoryCostKb",131072);
    json.UpdateInt("iterations",4);
    json.UpdateInt("parallelism",2);
    json.UpdateInt("saltLen",16);

    //  A secret (pepper) and/or ad may be used, but neither is stored in the returned PHC string.  The
    //  same values must be supplied to Argon2VerifyPassword for the password to verify.
    json.UpdateString("secret","application-wide-pepper");
    json.UpdateString("secretEncoding","utf-8");

    const char *phcHash = crypt.argon2HashPassword(password,json.emit());
    if (crypt.get_LastMethodSuccess() == false) {
        std::cout << crypt.lastErrorText() << "\r\n";
        return;
    }

    std::cout << phcHash << "\r\n";
    }