KRB5_RD_SAFE(3)

💖 KRB5_RD_SAFE(3) — the krb5_rd_safe / krb5_rd_priv page 💖

okay bestie, so this is the man page for krb5_rd_safe and krb5_rd_priv — they're the verifiers. the ones who check that your messages are actually real and not somebody being shady. 💅

✨ NAME ✨

krb5_rd_safe, krb5_rd_priv — verifies authenticity of messages 🔍

📚 LIBRARY 📚

Kerberos 5 Library (libkrb5, -lkrb5)

🎀 SYNOPSIS 🎀

#include <krb5.h>

krb5_error_code
krb5_rd_priv(krb5_context context, krb5_auth_context auth_context,
    const krb5_data *inbuf, krb5_data *outbuf,
    krb5_replay_data *outdata);

krb5_error_code
krb5_rd_safe(krb5_context context, krb5_auth_context auth_context,
    const krb5_data *inbuf, krb5_data *outbuf,
    krb5_replay_data *outdata);

like. look at them. twins. 👯‍♀️

🌸 DESCRIPTION 🌸

so here's the vibe: krb5_rd_safe() and krb5_rd_priv() both parse KRB-SAFE and KRB-PRIV messages — the ones that got made by krb5_mk_safe(3) and krb5_mk_priv(3), bestie, you know the ones 💖 — and they pull those messages out of inbuf and then verify the message's integrity. like a vibe check but for cryptography. if it's fake, they will KNOW. 🔥

the user data part of the message ends up in outbuf. that's the actual good stuff, the payload, the main character of the whole operation. 👑

the encryption state — including the keyblocks and the addresses — gets taken from auth_context. it's all in there already, you don't have to hand it over again. 🫶

and THEN — this is the fun bit — if the KRB5_AUTH_CONTEXT_RET_SEQUENCE flag or the KRB5_AUTH_CONTEXT_RET_TIME flag is set in the auth_context, then the sequence number and the time come back to you in the outdata parameter. it's giving "yes and here's the receipts". 🧾✨

ngl, no return-value lore on this page — the synopsis literally says both functions hand you a krb5_error_code, so check that. no cap. 😭

👀 SEE ALSO 👀

• krb5_auth_con_init(3)
• krb5_mk_priv(3)
• krb5_mk_safe(3)

the whole little friend group. go read them, they're all part of the same era. 🦋

written by the lovely people at HEIMDAL, dated May 1, 2006 — a classic, honestly, an absolute icon of a timestamp, and it ate 💅✨🎀