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authorAndré Fabian Silva Delgado <emulatorman@parabola.nu>2015-08-05 17:04:01 -0300
committerAndré Fabian Silva Delgado <emulatorman@parabola.nu>2015-08-05 17:04:01 -0300
commit57f0f512b273f60d52568b8c6b77e17f5636edc0 (patch)
tree5e910f0e82173f4ef4f51111366a3f1299037a7b /net/sunrpc/auth_generic.c
Initial import
Diffstat (limited to 'net/sunrpc/auth_generic.c')
-rw-r--r--net/sunrpc/auth_generic.c290
1 files changed, 290 insertions, 0 deletions
diff --git a/net/sunrpc/auth_generic.c b/net/sunrpc/auth_generic.c
new file mode 100644
index 000000000..41248b182
--- /dev/null
+++ b/net/sunrpc/auth_generic.c
@@ -0,0 +1,290 @@
+/*
+ * Generic RPC credential
+ *
+ * Copyright (C) 2008, Trond Myklebust <Trond.Myklebust@netapp.com>
+ */
+
+#include <linux/err.h>
+#include <linux/slab.h>
+#include <linux/types.h>
+#include <linux/module.h>
+#include <linux/sched.h>
+#include <linux/sunrpc/auth.h>
+#include <linux/sunrpc/clnt.h>
+#include <linux/sunrpc/debug.h>
+#include <linux/sunrpc/sched.h>
+
+#if IS_ENABLED(CONFIG_SUNRPC_DEBUG)
+# define RPCDBG_FACILITY RPCDBG_AUTH
+#endif
+
+#define RPC_MACHINE_CRED_USERID GLOBAL_ROOT_UID
+#define RPC_MACHINE_CRED_GROUPID GLOBAL_ROOT_GID
+
+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);
+
+struct rpc_cred *rpc_lookup_cred_nonblock(void)
+{
+ return rpcauth_lookupcred(&generic_auth, RPCAUTH_LOOKUP_RCU);
+}
+EXPORT_SYMBOL_GPL(rpc_lookup_cred_nonblock);
+
+/*
+ * Public call interface for looking up machine creds.
+ */
+struct rpc_cred *rpc_lookup_machine_cred(const char *service_name)
+{
+ struct auth_cred acred = {
+ .uid = RPC_MACHINE_CRED_USERID,
+ .gid = RPC_MACHINE_CRED_GROUPID,
+ .principal = service_name,
+ .machine_cred = 1,
+ };
+
+ dprintk("RPC: looking up machine cred for service %s\n",
+ service_name);
+ return generic_auth.au_ops->lookup_cred(&generic_auth, &acred, 0);
+}
+EXPORT_SYMBOL_GPL(rpc_lookup_machine_cred);
+
+static struct rpc_cred *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;
+
+ return auth->au_ops->lookup_cred(auth, acred, lookupflags);
+}
+
+/*
+ * 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;
+ gcred->acred.ac_flags = 0;
+ if (gcred->acred.group_info != NULL)
+ get_group_info(gcred->acred.group_info);
+ gcred->acred.machine_cred = acred->machine_cred;
+ gcred->acred.principal = acred->principal;
+
+ dprintk("RPC: allocated %s cred %p for uid %d gid %d\n",
+ gcred->acred.machine_cred ? "machine" : "generic",
+ gcred,
+ from_kuid(&init_user_ns, acred->uid),
+ from_kgid(&init_user_ns, 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);
+}
+
+static int
+machine_cred_match(struct auth_cred *acred, struct generic_cred *gcred, int flags)
+{
+ if (!gcred->acred.machine_cred ||
+ gcred->acred.principal != acred->principal ||
+ !uid_eq(gcred->acred.uid, acred->uid) ||
+ !gid_eq(gcred->acred.gid, acred->gid))
+ return 0;
+ return 1;
+}
+
+/*
+ * 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 (acred->machine_cred)
+ return machine_cred_match(acred, gcred, flags);
+
+ if (!uid_eq(gcred->acred.uid, acred->uid) ||
+ !gid_eq(gcred->acred.gid, acred->gid) ||
+ gcred->acred.machine_cred != 0)
+ 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 (!gid_eq(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 rpc_destroy_generic_auth(void)
+{
+ rpcauth_destroy_credcache(&generic_auth);
+}
+
+/*
+ * Test the the current time (now) against the underlying credential key expiry
+ * minus a timeout and setup notification.
+ *
+ * The normal case:
+ * If 'now' is before the key expiry minus RPC_KEY_EXPIRE_TIMEO, set
+ * the RPC_CRED_NOTIFY_TIMEOUT flag to setup the underlying credential
+ * rpc_credops crmatch routine to notify this generic cred when it's key
+ * expiration is within RPC_KEY_EXPIRE_TIMEO, and return 0.
+ *
+ * The error case:
+ * If the underlying cred lookup fails, return -EACCES.
+ *
+ * The 'almost' error case:
+ * If 'now' is within key expiry minus RPC_KEY_EXPIRE_TIMEO, but not within
+ * key expiry minus RPC_KEY_EXPIRE_FAIL, set the RPC_CRED_EXPIRE_SOON bit
+ * on the acred ac_flags and return 0.
+ */
+static int
+generic_key_timeout(struct rpc_auth *auth, struct rpc_cred *cred)
+{
+ struct auth_cred *acred = &container_of(cred, struct generic_cred,
+ gc_base)->acred;
+ struct rpc_cred *tcred;
+ int ret = 0;
+
+
+ /* Fast track for non crkey_timeout (no key) underlying credentials */
+ if (test_bit(RPC_CRED_NO_CRKEY_TIMEOUT, &acred->ac_flags))
+ return 0;
+
+ /* Fast track for the normal case */
+ if (test_bit(RPC_CRED_NOTIFY_TIMEOUT, &acred->ac_flags))
+ return 0;
+
+ /* lookup_cred either returns a valid referenced rpc_cred, or PTR_ERR */
+ tcred = auth->au_ops->lookup_cred(auth, acred, 0);
+ if (IS_ERR(tcred))
+ return -EACCES;
+
+ if (!tcred->cr_ops->crkey_timeout) {
+ set_bit(RPC_CRED_NO_CRKEY_TIMEOUT, &acred->ac_flags);
+ ret = 0;
+ goto out_put;
+ }
+
+ /* Test for the almost error case */
+ ret = tcred->cr_ops->crkey_timeout(tcred);
+ if (ret != 0) {
+ set_bit(RPC_CRED_KEY_EXPIRE_SOON, &acred->ac_flags);
+ ret = 0;
+ } else {
+ /* In case underlying cred key has been reset */
+ if (test_and_clear_bit(RPC_CRED_KEY_EXPIRE_SOON,
+ &acred->ac_flags))
+ dprintk("RPC: UID %d Credential key reset\n",
+ from_kuid(&init_user_ns, tcred->cr_uid));
+ /* set up fasttrack for the normal case */
+ set_bit(RPC_CRED_NOTIFY_TIMEOUT, &acred->ac_flags);
+ }
+
+out_put:
+ put_rpccred(tcred);
+ return ret;
+}
+
+static const struct rpc_authops generic_auth_ops = {
+ .owner = THIS_MODULE,
+ .au_name = "Generic",
+ .lookup_cred = generic_lookup_cred,
+ .crcreate = generic_create_cred,
+ .key_timeout = generic_key_timeout,
+};
+
+static struct rpc_auth generic_auth = {
+ .au_ops = &generic_auth_ops,
+ .au_count = ATOMIC_INIT(0),
+};
+
+static bool generic_key_to_expire(struct rpc_cred *cred)
+{
+ struct auth_cred *acred = &container_of(cred, struct generic_cred,
+ gc_base)->acred;
+ bool ret;
+
+ get_rpccred(cred);
+ ret = test_bit(RPC_CRED_KEY_EXPIRE_SOON, &acred->ac_flags);
+ put_rpccred(cred);
+
+ return ret;
+}
+
+static const struct rpc_credops generic_credops = {
+ .cr_name = "Generic cred",
+ .crdestroy = generic_destroy_cred,
+ .crbind = generic_bind_cred,
+ .crmatch = generic_match,
+ .crkey_to_expire = generic_key_to_expire,
+};