1 files changed, 242 insertions, 0 deletions
diff --git a/net/sunrpc/auth_unix.c b/net/sunrpc/auth_unix.c
new file mode 100644
index 000000000000..4ff297a9b15b
--- /dev/null
+++ b/net/sunrpc/auth_unix.c
@@ -0,0 +1,242 @@
+/*
+ * linux/net/sunrpc/auth_unix.c
+ *
+ * UNIX-style authentication; no AUTH_SHORT support
+ *
+ * Copyright (C) 1996, Olaf Kirch <okir@monad.swb.de>
+ */
+
+#include <linux/types.h>
+#include <linux/sched.h>
+#include <linux/module.h>
+#include <linux/socket.h>
+#include <linux/in.h>
+#include <linux/sunrpc/clnt.h>
+#include <linux/sunrpc/auth.h>
+
+#define NFS_NGROUPS	16
+
+struct unx_cred {
+	struct rpc_cred		uc_base;
+	gid_t			uc_gid;
+	gid_t			uc_gids[NFS_NGROUPS];
+};
+#define uc_uid			uc_base.cr_uid
+#define uc_count		uc_base.cr_count
+#define uc_flags		uc_base.cr_flags
+#define uc_expire		uc_base.cr_expire
+
+#define UNX_CRED_EXPIRE		(60 * HZ)
+
+#define UNX_WRITESLACK		(21 + (UNX_MAXNODENAME >> 2))
+
+#ifdef RPC_DEBUG
+# define RPCDBG_FACILITY	RPCDBG_AUTH
+#endif
+
+static struct rpc_auth		unix_auth;
+static struct rpc_cred_cache	unix_cred_cache;
+static struct rpc_credops	unix_credops;
+
+static struct rpc_auth *
+unx_create(struct rpc_clnt *clnt, rpc_authflavor_t flavor)
+{
+	dprintk("RPC: creating UNIX authenticator for client %p\n", clnt);
+	if (atomic_inc_return(&unix_auth.au_count) == 0)
+		unix_cred_cache.nextgc = jiffies + (unix_cred_cache.expire >> 1);
+	return &unix_auth;
+}
+
+static void
+unx_destroy(struct rpc_auth *auth)
+{
+	dprintk("RPC: destroying UNIX authenticator %p\n", auth);
+	rpcauth_free_credcache(auth);
+}
+
+/*
+ * Lookup AUTH_UNIX creds for current process
+ */
+static struct rpc_cred *
+unx_lookup_cred(struct rpc_auth *auth, struct auth_cred *acred, int flags)
+{
+	return rpcauth_lookup_credcache(auth, acred, flags);
+}
+
+static struct rpc_cred *
+unx_create_cred(struct rpc_auth *auth, struct auth_cred *acred, int flags)
+{
+	struct unx_cred	*cred;
+	int		i;
+
+	dprintk("RPC:      allocating UNIX cred for uid %d gid %d\n",
+				acred->uid, acred->gid);
+
+	if (!(cred = (struct unx_cred *) kmalloc(sizeof(*cred), GFP_KERNEL)))
+		return ERR_PTR(-ENOMEM);
+
+	atomic_set(&cred->uc_count, 1);
+	cred->uc_flags = RPCAUTH_CRED_UPTODATE;
+	if (flags & RPC_TASK_ROOTCREDS) {
+		cred->uc_uid = 0;
+		cred->uc_gid = 0;
+		cred->uc_gids[0] = NOGROUP;
+	} else {
+		int groups = acred->group_info->ngroups;
+		if (groups > NFS_NGROUPS)
+			groups = NFS_NGROUPS;
+
+		cred->uc_uid = acred->uid;
+		cred->uc_gid = acred->gid;
+		for (i = 0; i < groups; i++)
+			cred->uc_gids[i] = GROUP_AT(acred->group_info, i);
+		if (i < NFS_NGROUPS)
+		  cred->uc_gids[i] = NOGROUP;
+	}
+	cred->uc_base.cr_ops = &unix_credops;
+
+	return (struct rpc_cred *) cred;
+}
+
+static void
+unx_destroy_cred(struct rpc_cred *cred)
+{
+	kfree(cred);
+}
+
+/*
+ * Match credentials against current process creds.
+ * The root_override argument takes care of cases where the caller may
+ * request root creds (e.g. for NFS swapping).
+ */
+static int
+unx_match(struct auth_cred *acred, struct rpc_cred *rcred, int taskflags)
+{
+	struct unx_cred	*cred = (struct unx_cred *) rcred;
+	int		i;
+
+	if (!(taskflags & RPC_TASK_ROOTCREDS)) {
+		int groups;
+
+		if (cred->uc_uid != acred->uid
+		 || cred->uc_gid != acred->gid)
+			return 0;
+
+		groups = acred->group_info->ngroups;
+		if (groups > NFS_NGROUPS)
+			groups = NFS_NGROUPS;
+		for (i = 0; i < groups ; i++)
+			if (cred->uc_gids[i] != GROUP_AT(acred->group_info, i))
+				return 0;
+		return 1;
+	}
+	return (cred->uc_uid == 0
+	     && cred->uc_gid == 0
+	     && cred->uc_gids[0] == (gid_t) NOGROUP);
+}
+
+/*
+ * Marshal credentials.
+ * Maybe we should keep a cached credential for performance reasons.
+ */
+static u32 *
+unx_marshal(struct rpc_task *task, u32 *p)
+{
+	struct rpc_clnt	*clnt = task->tk_client;
+	struct unx_cred	*cred = (struct unx_cred *) task->tk_msg.rpc_cred;
+	u32		*base, *hold;
+	int		i;
+
+	*p++ = htonl(RPC_AUTH_UNIX);
+	base = p++;
+	*p++ = htonl(jiffies/HZ);
+
+	/*
+	 * Copy the UTS nodename captured when the client was created.
+	 */
+	p = xdr_encode_array(p, clnt->cl_nodename, clnt->cl_nodelen);
+
+	*p++ = htonl((u32) cred->uc_uid);
+	*p++ = htonl((u32) cred->uc_gid);
+	hold = p++;
+	for (i = 0; i < 16 && cred->uc_gids[i] != (gid_t) NOGROUP; i++)
+		*p++ = htonl((u32) cred->uc_gids[i]);
+	*hold = htonl(p - hold - 1);		/* gid array length */
+	*base = htonl((p - base - 1) << 2);	/* cred length */
+
+	*p++ = htonl(RPC_AUTH_NULL);
+	*p++ = htonl(0);
+
+	return p;
+}
+
+/*
+ * Refresh credentials. This is a no-op for AUTH_UNIX
+ */
+static int
+unx_refresh(struct rpc_task *task)
+{
+	task->tk_msg.rpc_cred->cr_flags |= RPCAUTH_CRED_UPTODATE;
+	return 0;
+}
+
+static u32 *
+unx_validate(struct rpc_task *task, u32 *p)
+{
+	rpc_authflavor_t	flavor;
+	u32			size;
+
+	flavor = ntohl(*p++);
+	if (flavor != RPC_AUTH_NULL &&
+	    flavor != RPC_AUTH_UNIX &&
+	    flavor != RPC_AUTH_SHORT) {
+		printk("RPC: bad verf flavor: %u\n", flavor);
+		return NULL;
+	}
+
+	size = ntohl(*p++);
+	if (size > RPC_MAX_AUTH_SIZE) {
+		printk("RPC: giant verf size: %u\n", size);
+		return NULL;
+	}
+	task->tk_auth->au_rslack = (size >> 2) + 2;
+	p += (size >> 2);
+
+	return p;
+}
+
+struct rpc_authops	authunix_ops = {
+	.owner		= THIS_MODULE,
+	.au_flavor	= RPC_AUTH_UNIX,
+#ifdef RPC_DEBUG
+	.au_name	= "UNIX",
+#endif
+	.create		= unx_create,
+	.destroy	= unx_destroy,
+	.lookup_cred	= unx_lookup_cred,
+	.crcreate	= unx_create_cred,
+};
+
+static
+struct rpc_cred_cache	unix_cred_cache = {
+	.expire		= UNX_CRED_EXPIRE,
+};
+
+static
+struct rpc_auth		unix_auth = {
+	.au_cslack	= UNX_WRITESLACK,
+	.au_rslack	= 2,			/* assume AUTH_NULL verf */
+	.au_ops		= &authunix_ops,
+	.au_count	= ATOMIC_INIT(0),
+	.au_credcache	= &unix_cred_cache,
+};
+
+static
+struct rpc_credops	unix_credops = {
+	.cr_name	= "AUTH_UNIX",
+	.crdestroy	= unx_destroy_cred,
+	.crmatch	= unx_match,
+	.crmarshal	= unx_marshal,
+	.crrefresh	= unx_refresh,
+	.crvalidate	= unx_validate,
+};