/* * Generic RPC credential * * Copyright (C) 2008, Trond Myklebust */ #include #include #include #include #include #include #include #include #include #ifdef RPC_DEBUG # define RPCDBG_FACILITY RPCDBG_AUTH #endif #define RPC_MACHINE_CRED_USERID ((uid_t)0) #define RPC_MACHINE_CRED_GROUPID ((gid_t)0) struct generic_cred { struct rpc_cred gc_base; struct auth_cred acred; }; static struct rpc_auth generic_auth; static const struct rpc_credops generic_credops; /* * Public call interface */ struct rpc_cred *rpc_lookup_cred(void) { return rpcauth_lookupcred(&generic_auth, 0); } EXPORT_SYMBOL_GPL(rpc_lookup_cred); /* * Public call interface for looking up machine creds. */ struct rpc_cred *rpc_lookup_machine_cred(void) { struct auth_cred acred = { .uid = RPC_MACHINE_CRED_USERID, .gid = RPC_MACHINE_CRED_GROUPID, .machine_cred = 1, }; dprintk("RPC: looking up machine cred\n"); return generic_auth.au_ops->lookup_cred(&generic_auth, &acred, 0); } EXPORT_SYMBOL_GPL(rpc_lookup_machine_cred); static void generic_bind_cred(struct rpc_task *task, struct rpc_cred *cred, int lookupflags) { struct rpc_auth *auth = task->tk_client->cl_auth; struct auth_cred *acred = &container_of(cred, struct generic_cred, gc_base)->acred; struct rpc_cred *ret; ret = auth->au_ops->lookup_cred(auth, acred, lookupflags); if (!IS_ERR(ret)) task->tk_msg.rpc_cred = ret; else task->tk_status = PTR_ERR(ret); } /* * Lookup generic creds for current process */ static struct rpc_cred * generic_lookup_cred(struct rpc_auth *auth, struct auth_cred *acred, int flags) { return rpcauth_lookup_credcache(&generic_auth, acred, flags); } static struct rpc_cred * generic_create_cred(struct rpc_auth *auth, struct auth_cred *acred, int flags) { struct generic_cred *gcred; gcred = kmalloc(sizeof(*gcred), GFP_KERNEL); if (gcred == NULL) return ERR_PTR(-ENOMEM); rpcauth_init_cred(&gcred->gc_base, acred, &generic_auth, &generic_credops); gcred->gc_base.cr_flags = 1UL << RPCAUTH_CRED_UPTODATE; gcred->acred.uid = acred->uid; gcred->acred.gid = acred->gid; gcred->acred.group_info = acred->group_info; if (gcred->acred.group_info != NULL) get_group_info(gcred->acred.group_info); gcred->acred.machine_cred = acred->machine_cred; dprintk("RPC: allocated %s cred %p for uid %d gid %d\n", gcred->acred.machine_cred ? "machine" : "generic", gcred, acred->uid, acred->gid); return &gcred->gc_base; } static void generic_free_cred(struct rpc_cred *cred) { struct generic_cred *gcred = container_of(cred, struct generic_cred, gc_base); dprintk("RPC: generic_free_cred %p\n", gcred); if (gcred->acred.group_info != NULL) put_group_info(gcred->acred.group_info); kfree(gcred); } static void generic_free_cred_callback(struct rcu_head *head) { struct rpc_cred *cred = container_of(head, struct rpc_cred, cr_rcu); generic_free_cred(cred); } static void generic_destroy_cred(struct rpc_cred *cred) { call_rcu(&cred->cr_rcu, generic_free_cred_callback); } /* * Match credentials against current process creds. */ static int generic_match(struct auth_cred *acred, struct rpc_cred *cred, int flags) { struct generic_cred *gcred = container_of(cred, struct generic_cred, gc_base); int i; if (gcred->acred.uid != acred->uid || gcred->acred.gid != acred->gid || gcred->acred.machine_cred != acred->machine_cred) goto out_nomatch; /* Optimisation in the case where pointers are identical... */ if (gcred->acred.group_info == acred->group_info) goto out_match; /* Slow path... */ if (gcred->acred.group_info->ngroups != acred->group_info->ngroups) goto out_nomatch; for (i = 0; i < gcred->acred.group_info->ngroups; i++) { if (GROUP_AT(gcred->acred.group_info, i) != GROUP_AT(acred->group_info, i)) goto out_nomatch; } out_match: return 1; out_nomatch: return 0; } int __init rpc_init_generic_auth(void) { return rpcauth_init_credcache(&generic_auth); } void __exit rpc_destroy_generic_auth(void) { rpcauth_destroy_credcache(&generic_auth); } static const struct rpc_authops generic_auth_ops = { .owner = THIS_MODULE, .au_name = "Generic", .lookup_cred = generic_lookup_cred, .crcreate = generic_create_cred, }; static struct rpc_auth generic_auth = { .au_ops = &generic_auth_ops, .au_count = ATOMIC_INIT(0), }; static const struct rpc_credops generic_credops = { .cr_name = "Generic cred", .crdestroy = generic_destroy_cred, .crbind = generic_bind_cred, .crmatch = generic_match, };