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,
+};