linux-stable/include/linux/sunrpc/svcauth.h
Chuck Lever 78c542f916 SUNRPC: Add enum svc_auth_status
In addition to the benefits of using an enum rather than a set of
macros, we now have a named type that can improve static type
checking of function return values.

As part of this change, I removed a stale comment from svcauth.h;
the return values from current implementations of the
auth_ops::release method are all zero/negative errno, not the SVC_OK
enum values as the old comment suggested.

Suggested-by: NeilBrown <neilb@suse.de>
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
2023-08-29 17:45:22 -04:00

181 lines
5.8 KiB
C

/* SPDX-License-Identifier: GPL-2.0 */
/*
* linux/include/linux/sunrpc/svcauth.h
*
* RPC server-side authentication stuff.
*
* Copyright (C) 1995, 1996 Olaf Kirch <okir@monad.swb.de>
*/
#ifndef _LINUX_SUNRPC_SVCAUTH_H_
#define _LINUX_SUNRPC_SVCAUTH_H_
#include <linux/string.h>
#include <linux/sunrpc/msg_prot.h>
#include <linux/sunrpc/cache.h>
#include <linux/sunrpc/gss_api.h>
#include <linux/hash.h>
#include <linux/stringhash.h>
#include <linux/cred.h>
struct svc_cred {
kuid_t cr_uid;
kgid_t cr_gid;
struct group_info *cr_group_info;
u32 cr_flavor; /* pseudoflavor */
/* name of form servicetype/hostname@REALM, passed down by
* gss-proxy: */
char *cr_raw_principal;
/* name of form servicetype@hostname, passed down by
* rpc.svcgssd, or computed from the above: */
char *cr_principal;
char *cr_targ_princ;
struct gss_api_mech *cr_gss_mech;
};
static inline void init_svc_cred(struct svc_cred *cred)
{
cred->cr_group_info = NULL;
cred->cr_raw_principal = NULL;
cred->cr_principal = NULL;
cred->cr_targ_princ = NULL;
cred->cr_gss_mech = NULL;
}
static inline void free_svc_cred(struct svc_cred *cred)
{
if (cred->cr_group_info)
put_group_info(cred->cr_group_info);
kfree(cred->cr_raw_principal);
kfree(cred->cr_principal);
kfree(cred->cr_targ_princ);
gss_mech_put(cred->cr_gss_mech);
init_svc_cred(cred);
}
struct svc_rqst; /* forward decl */
struct in6_addr;
/* Authentication is done in the context of a domain.
*
* Currently, the nfs server uses the auth_domain to stand
* for the "client" listed in /etc/exports.
*
* More generally, a domain might represent a group of clients using
* a common mechanism for authentication and having a common mapping
* between local identity (uid) and network identity. All clients
* in a domain have similar general access rights. Each domain can
* contain multiple principals which will have different specific right
* based on normal Discretionary Access Control.
*
* A domain is created by an authentication flavour module based on name
* only. Userspace then fills in detail on demand.
*
* In the case of auth_unix and auth_null, the auth_domain is also
* associated with entries in another cache representing the mapping
* of ip addresses to the given client.
*/
struct auth_domain {
struct kref ref;
struct hlist_node hash;
char *name;
struct auth_ops *flavour;
struct rcu_head rcu_head;
};
enum svc_auth_status {
SVC_GARBAGE = 1,
SVC_SYSERR,
SVC_VALID,
SVC_NEGATIVE,
SVC_OK,
SVC_DROP,
SVC_CLOSE,
SVC_DENIED,
SVC_PENDING,
SVC_COMPLETE,
};
/*
* Each authentication flavour registers an auth_ops
* structure.
* name is simply the name.
* flavour gives the auth flavour. It determines where the flavour is registered
* accept() is given a request and should verify it.
* It should inspect the authenticator and verifier, and possibly the data.
* If there is a problem with the authentication *authp should be set.
* The return value of accept() can indicate:
* OK - authorised. client and credential are set in rqstp.
* reqbuf points to arguments
* resbuf points to good place for results. verfier
* is (probably) already in place. Certainly space is
* reserved for it.
* DROP - simply drop the request. It may have been deferred
* CLOSE - like SVC_DROP, but request is definitely lost.
* If there is a tcp connection, it should be closed.
* GARBAGE - rpc garbage_args error
* SYSERR - rpc system_err error
* DENIED - authp holds reason for denial.
* COMPLETE - the reply is encoded already and ready to be sent; no
* further processing is necessary. (This is used for processing
* null procedure calls which are used to set up encryption
* contexts.)
*
* accept is passed the proc number so that it can accept NULL rpc requests
* even if it cannot authenticate the client (as is sometimes appropriate).
*
* release() is given a request after the procedure has been run.
* It should sign/encrypt the results if needed
*
* domain_release()
* This call releases a domain.
*
* set_client()
* Givens a pending request (struct svc_rqst), finds and assigns
* an appropriate 'auth_domain' as the client.
*/
struct auth_ops {
char * name;
struct module *owner;
int flavour;
enum svc_auth_status (*accept)(struct svc_rqst *rqstp);
int (*release)(struct svc_rqst *rqstp);
void (*domain_release)(struct auth_domain *dom);
enum svc_auth_status (*set_client)(struct svc_rqst *rqstp);
};
struct svc_xprt;
extern enum svc_auth_status svc_authenticate(struct svc_rqst *rqstp);
extern int svc_authorise(struct svc_rqst *rqstp);
extern enum svc_auth_status svc_set_client(struct svc_rqst *rqstp);
extern int svc_auth_register(rpc_authflavor_t flavor, struct auth_ops *aops);
extern void svc_auth_unregister(rpc_authflavor_t flavor);
extern struct auth_domain *unix_domain_find(char *name);
extern void auth_domain_put(struct auth_domain *item);
extern struct auth_domain *auth_domain_lookup(char *name, struct auth_domain *new);
extern struct auth_domain *auth_domain_find(char *name);
extern void svcauth_unix_purge(struct net *net);
extern void svcauth_unix_info_release(struct svc_xprt *xpt);
extern enum svc_auth_status svcauth_unix_set_client(struct svc_rqst *rqstp);
extern int unix_gid_cache_create(struct net *net);
extern void unix_gid_cache_destroy(struct net *net);
/*
* The <stringhash.h> functions are good enough that we don't need to
* use hash_32() on them; just extracting the high bits is enough.
*/
static inline unsigned long hash_str(char const *name, int bits)
{
return hashlen_hash(hashlen_string(NULL, name)) >> (32 - bits);
}
static inline unsigned long hash_mem(char const *buf, int length, int bits)
{
return full_name_hash(NULL, buf, length) >> (32 - bits);
}
#endif /* _LINUX_SUNRPC_SVCAUTH_H_ */