RPC_CLNT_AUTH(3)

💖 RPC_CLNT_AUTH(3) 💖

okay bestie, so this is a Library Functions Manual page, section 3 of the manual, and the whole vibe is client side RPC authentication. no cap. let's get into it 🦋

✨ NAME ✨

auth_destroy, authnone_create, authsys_create, authsys_create_default — library routines for client side remote procedure call authentication 👑

🌸 SYNOPSIS 🌸

#include <rpc/rpc.h>

void
auth_destroy(AUTH *auth);

AUTH *
authnone_create(void);

AUTH *
authsys_create(const char *host, const uid_t uid, const gid_t gid,
    const int len, const gid_t *aup_gids);

AUTH *
authsys_create_default(void);

like. look at those signatures. they're serving 💅

🎀 DESCRIPTION 🎀

so these routines are part of the RPC library, and what that library does is let C language programs make procedure calls on other machines across the network — with whatever authentication you want. desired authentication. your choice, your rules. ✨

the way these get called is normally after you've created the CLIENT handle. like, CLIENT first, auth second, that's the order, don't fight it.

then: the cl_auth field of the CLIENT structure should be initialized by the AUTH structure that some of the following routines hand back to you. 💖

and the client's authentication information? it gets passed to the server when the RPC call is made. that's the whole point. that's the moment. 🌈

heads up bestie: only the NULL and the SYS style of authentication is discussed here. the others are simply not this page's business. iykyk.

🧚 Routines 🧚

• auth_destroy() — okay so this one is a function macro (yes, a macro, not a regular function, stay woke) that destroys the authentication information associated with auth. destruction usually involves deallocation of private data structures. and here's the scary part: the use of auth is undefined after calling auth_destroy(). undefined!! so like, do NOT touch it afterwards. it's gone. it's in the past. move on. 💀
• authnone_create() — create and return an RPC authentication handle that passes nonusable authentication information with each remote procedure call. and fun fact: this is the default authentication used by RPC. the default. the moment. the icon. 🎀
• authsys_create() — create and return an RPC authentication handle that contains AUTH_SYS authentication information. now let's break down the arguments, bestie, because there's a lot:
  • host — the name of the machine on which the information was created 🖥️
  • uid — the user's user ID
  • gid — the user's current group ID
  • len and aup_gids — these two refer to a counted array of groups to which the user belongs. len is the count, aup_gids is the array. they're a package deal, you can't split them up, that's the rules 🫶
• authsys_create_default() — literally just calls authsys_create() with the appropriate arguments. that's it. that's the whole job. lowkey the easiest one here, and honestly? slay. ✨

🌟 AVAILABILITY 🌟

these functions are part of libtirpc. 🧚‍♀️

💜 SEE ALSO 💜

rpc(3), rpc_clnt_calls(3), rpc_clnt_create(3)

go read those too, bestie, they're all connected, it's giving ✨lore✨

and that's the page!! 🎉 this one came from Debian and it's dated May 7, 1993 — yes, 1993, this manual page is older than basically everyone you know and it's still running things. iconic behavior honestly. periodt. 💅👑🌸