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authorDaniel Baumann <daniel.baumann@progress-linux.org>2024-04-11 08:27:49 +0000
committerDaniel Baumann <daniel.baumann@progress-linux.org>2024-04-11 08:27:49 +0000
commitace9429bb58fd418f0c81d4c2835699bddf6bde6 (patch)
treeb2d64bc10158fdd5497876388cd68142ca374ed3 /fs/nfs/nfs4idmap.c
parentInitial commit. (diff)
downloadlinux-ace9429bb58fd418f0c81d4c2835699bddf6bde6.tar.xz
linux-ace9429bb58fd418f0c81d4c2835699bddf6bde6.zip
Adding upstream version 6.6.15.upstream/6.6.15
Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>
Diffstat (limited to 'fs/nfs/nfs4idmap.c')
-rw-r--r--fs/nfs/nfs4idmap.c806
1 files changed, 806 insertions, 0 deletions
diff --git a/fs/nfs/nfs4idmap.c b/fs/nfs/nfs4idmap.c
new file mode 100644
index 0000000000..25a7c771cf
--- /dev/null
+++ b/fs/nfs/nfs4idmap.c
@@ -0,0 +1,806 @@
+/*
+ * fs/nfs/idmap.c
+ *
+ * UID and GID to name mapping for clients.
+ *
+ * Copyright (c) 2002 The Regents of the University of Michigan.
+ * All rights reserved.
+ *
+ * Marius Aamodt Eriksen <marius@umich.edu>
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ *
+ * 1. Redistributions of source code must retain the above copyright
+ * notice, this list of conditions and the following disclaimer.
+ * 2. Redistributions in binary form must reproduce the above copyright
+ * notice, this list of conditions and the following disclaimer in the
+ * documentation and/or other materials provided with the distribution.
+ * 3. Neither the name of the University nor the names of its
+ * contributors may be used to endorse or promote products derived
+ * from this software without specific prior written permission.
+ *
+ * THIS SOFTWARE IS PROVIDED ``AS IS'' AND ANY EXPRESS OR IMPLIED
+ * WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF
+ * MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
+ * DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
+ * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
+ * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
+ * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR
+ * BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF
+ * LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING
+ * NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
+ * SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ */
+#include <linux/types.h>
+#include <linux/parser.h>
+#include <linux/fs.h>
+#include <net/net_namespace.h>
+#include <linux/sunrpc/rpc_pipe_fs.h>
+#include <linux/nfs_fs.h>
+#include <linux/nfs_fs_sb.h>
+#include <linux/key.h>
+#include <linux/keyctl.h>
+#include <linux/key-type.h>
+#include <keys/user-type.h>
+#include <keys/request_key_auth-type.h>
+#include <linux/module.h>
+#include <linux/user_namespace.h>
+
+#include "internal.h"
+#include "netns.h"
+#include "nfs4idmap.h"
+#include "nfs4trace.h"
+
+#define NFS_UINT_MAXLEN 11
+
+static const struct cred *id_resolver_cache;
+static struct key_type key_type_id_resolver_legacy;
+
+struct idmap_legacy_upcalldata {
+ struct rpc_pipe_msg pipe_msg;
+ struct idmap_msg idmap_msg;
+ struct key *authkey;
+ struct idmap *idmap;
+};
+
+struct idmap {
+ struct rpc_pipe_dir_object idmap_pdo;
+ struct rpc_pipe *idmap_pipe;
+ struct idmap_legacy_upcalldata *idmap_upcall_data;
+ struct mutex idmap_mutex;
+ struct user_namespace *user_ns;
+};
+
+static struct user_namespace *idmap_userns(const struct idmap *idmap)
+{
+ if (idmap && idmap->user_ns)
+ return idmap->user_ns;
+ return &init_user_ns;
+}
+
+/**
+ * nfs_fattr_init_names - initialise the nfs_fattr owner_name/group_name fields
+ * @fattr: fully initialised struct nfs_fattr
+ * @owner_name: owner name string cache
+ * @group_name: group name string cache
+ */
+void nfs_fattr_init_names(struct nfs_fattr *fattr,
+ struct nfs4_string *owner_name,
+ struct nfs4_string *group_name)
+{
+ fattr->owner_name = owner_name;
+ fattr->group_name = group_name;
+}
+
+static void nfs_fattr_free_owner_name(struct nfs_fattr *fattr)
+{
+ fattr->valid &= ~NFS_ATTR_FATTR_OWNER_NAME;
+ kfree(fattr->owner_name->data);
+}
+
+static void nfs_fattr_free_group_name(struct nfs_fattr *fattr)
+{
+ fattr->valid &= ~NFS_ATTR_FATTR_GROUP_NAME;
+ kfree(fattr->group_name->data);
+}
+
+static bool nfs_fattr_map_owner_name(struct nfs_server *server, struct nfs_fattr *fattr)
+{
+ struct nfs4_string *owner = fattr->owner_name;
+ kuid_t uid;
+
+ if (!(fattr->valid & NFS_ATTR_FATTR_OWNER_NAME))
+ return false;
+ if (nfs_map_name_to_uid(server, owner->data, owner->len, &uid) == 0) {
+ fattr->uid = uid;
+ fattr->valid |= NFS_ATTR_FATTR_OWNER;
+ }
+ return true;
+}
+
+static bool nfs_fattr_map_group_name(struct nfs_server *server, struct nfs_fattr *fattr)
+{
+ struct nfs4_string *group = fattr->group_name;
+ kgid_t gid;
+
+ if (!(fattr->valid & NFS_ATTR_FATTR_GROUP_NAME))
+ return false;
+ if (nfs_map_group_to_gid(server, group->data, group->len, &gid) == 0) {
+ fattr->gid = gid;
+ fattr->valid |= NFS_ATTR_FATTR_GROUP;
+ }
+ return true;
+}
+
+/**
+ * nfs_fattr_free_names - free up the NFSv4 owner and group strings
+ * @fattr: a fully initialised nfs_fattr structure
+ */
+void nfs_fattr_free_names(struct nfs_fattr *fattr)
+{
+ if (fattr->valid & NFS_ATTR_FATTR_OWNER_NAME)
+ nfs_fattr_free_owner_name(fattr);
+ if (fattr->valid & NFS_ATTR_FATTR_GROUP_NAME)
+ nfs_fattr_free_group_name(fattr);
+}
+
+/**
+ * nfs_fattr_map_and_free_names - map owner/group strings into uid/gid and free
+ * @server: pointer to the filesystem nfs_server structure
+ * @fattr: a fully initialised nfs_fattr structure
+ *
+ * This helper maps the cached NFSv4 owner/group strings in fattr into
+ * their numeric uid/gid equivalents, and then frees the cached strings.
+ */
+void nfs_fattr_map_and_free_names(struct nfs_server *server, struct nfs_fattr *fattr)
+{
+ if (nfs_fattr_map_owner_name(server, fattr))
+ nfs_fattr_free_owner_name(fattr);
+ if (nfs_fattr_map_group_name(server, fattr))
+ nfs_fattr_free_group_name(fattr);
+}
+
+int nfs_map_string_to_numeric(const char *name, size_t namelen, __u32 *res)
+{
+ unsigned long val;
+ char buf[16];
+
+ if (memchr(name, '@', namelen) != NULL || namelen >= sizeof(buf))
+ return 0;
+ memcpy(buf, name, namelen);
+ buf[namelen] = '\0';
+ if (kstrtoul(buf, 0, &val) != 0)
+ return 0;
+ *res = val;
+ return 1;
+}
+EXPORT_SYMBOL_GPL(nfs_map_string_to_numeric);
+
+static int nfs_map_numeric_to_string(__u32 id, char *buf, size_t buflen)
+{
+ return snprintf(buf, buflen, "%u", id);
+}
+
+static struct key_type key_type_id_resolver = {
+ .name = "id_resolver",
+ .preparse = user_preparse,
+ .free_preparse = user_free_preparse,
+ .instantiate = generic_key_instantiate,
+ .revoke = user_revoke,
+ .destroy = user_destroy,
+ .describe = user_describe,
+ .read = user_read,
+};
+
+int nfs_idmap_init(void)
+{
+ struct cred *cred;
+ struct key *keyring;
+ int ret = 0;
+
+ printk(KERN_NOTICE "NFS: Registering the %s key type\n",
+ key_type_id_resolver.name);
+
+ cred = prepare_kernel_cred(&init_task);
+ if (!cred)
+ return -ENOMEM;
+
+ keyring = keyring_alloc(".id_resolver",
+ GLOBAL_ROOT_UID, GLOBAL_ROOT_GID, cred,
+ (KEY_POS_ALL & ~KEY_POS_SETATTR) |
+ KEY_USR_VIEW | KEY_USR_READ,
+ KEY_ALLOC_NOT_IN_QUOTA, NULL, NULL);
+ if (IS_ERR(keyring)) {
+ ret = PTR_ERR(keyring);
+ goto failed_put_cred;
+ }
+
+ ret = register_key_type(&key_type_id_resolver);
+ if (ret < 0)
+ goto failed_put_key;
+
+ ret = register_key_type(&key_type_id_resolver_legacy);
+ if (ret < 0)
+ goto failed_reg_legacy;
+
+ set_bit(KEY_FLAG_ROOT_CAN_CLEAR, &keyring->flags);
+ cred->thread_keyring = keyring;
+ cred->jit_keyring = KEY_REQKEY_DEFL_THREAD_KEYRING;
+ id_resolver_cache = cred;
+ return 0;
+
+failed_reg_legacy:
+ unregister_key_type(&key_type_id_resolver);
+failed_put_key:
+ key_put(keyring);
+failed_put_cred:
+ put_cred(cred);
+ return ret;
+}
+
+void nfs_idmap_quit(void)
+{
+ key_revoke(id_resolver_cache->thread_keyring);
+ unregister_key_type(&key_type_id_resolver);
+ unregister_key_type(&key_type_id_resolver_legacy);
+ put_cred(id_resolver_cache);
+}
+
+/*
+ * Assemble the description to pass to request_key()
+ * This function will allocate a new string and update dest to point
+ * at it. The caller is responsible for freeing dest.
+ *
+ * On error 0 is returned. Otherwise, the length of dest is returned.
+ */
+static ssize_t nfs_idmap_get_desc(const char *name, size_t namelen,
+ const char *type, size_t typelen, char **desc)
+{
+ char *cp;
+ size_t desclen = typelen + namelen + 2;
+
+ *desc = kmalloc(desclen, GFP_KERNEL);
+ if (!*desc)
+ return -ENOMEM;
+
+ cp = *desc;
+ memcpy(cp, type, typelen);
+ cp += typelen;
+ *cp++ = ':';
+
+ memcpy(cp, name, namelen);
+ cp += namelen;
+ *cp = '\0';
+ return desclen;
+}
+
+static struct key *nfs_idmap_request_key(const char *name, size_t namelen,
+ const char *type, struct idmap *idmap)
+{
+ char *desc;
+ struct key *rkey = ERR_PTR(-EAGAIN);
+ ssize_t ret;
+
+ ret = nfs_idmap_get_desc(name, namelen, type, strlen(type), &desc);
+ if (ret < 0)
+ return ERR_PTR(ret);
+
+ if (!idmap->user_ns || idmap->user_ns == &init_user_ns)
+ rkey = request_key(&key_type_id_resolver, desc, "");
+ if (IS_ERR(rkey)) {
+ mutex_lock(&idmap->idmap_mutex);
+ rkey = request_key_with_auxdata(&key_type_id_resolver_legacy,
+ desc, NULL, "", 0, idmap);
+ mutex_unlock(&idmap->idmap_mutex);
+ }
+ if (!IS_ERR(rkey))
+ set_bit(KEY_FLAG_ROOT_CAN_INVAL, &rkey->flags);
+
+ kfree(desc);
+ return rkey;
+}
+
+static ssize_t nfs_idmap_get_key(const char *name, size_t namelen,
+ const char *type, void *data,
+ size_t data_size, struct idmap *idmap)
+{
+ const struct cred *saved_cred;
+ struct key *rkey;
+ const struct user_key_payload *payload;
+ ssize_t ret;
+
+ saved_cred = override_creds(id_resolver_cache);
+ rkey = nfs_idmap_request_key(name, namelen, type, idmap);
+ revert_creds(saved_cred);
+
+ if (IS_ERR(rkey)) {
+ ret = PTR_ERR(rkey);
+ goto out;
+ }
+
+ rcu_read_lock();
+ rkey->perm |= KEY_USR_VIEW;
+
+ ret = key_validate(rkey);
+ if (ret < 0)
+ goto out_up;
+
+ payload = user_key_payload_rcu(rkey);
+ if (IS_ERR_OR_NULL(payload)) {
+ ret = PTR_ERR(payload);
+ goto out_up;
+ }
+
+ ret = payload->datalen;
+ if (ret > 0 && ret <= data_size)
+ memcpy(data, payload->data, ret);
+ else
+ ret = -EINVAL;
+
+out_up:
+ rcu_read_unlock();
+ key_put(rkey);
+out:
+ return ret;
+}
+
+/* ID -> Name */
+static ssize_t nfs_idmap_lookup_name(__u32 id, const char *type, char *buf,
+ size_t buflen, struct idmap *idmap)
+{
+ char id_str[NFS_UINT_MAXLEN];
+ int id_len;
+ ssize_t ret;
+
+ id_len = nfs_map_numeric_to_string(id, id_str, sizeof(id_str));
+ ret = nfs_idmap_get_key(id_str, id_len, type, buf, buflen, idmap);
+ if (ret < 0)
+ return -EINVAL;
+ return ret;
+}
+
+/* Name -> ID */
+static int nfs_idmap_lookup_id(const char *name, size_t namelen, const char *type,
+ __u32 *id, struct idmap *idmap)
+{
+ char id_str[NFS_UINT_MAXLEN];
+ long id_long;
+ ssize_t data_size;
+ int ret = 0;
+
+ data_size = nfs_idmap_get_key(name, namelen, type, id_str, NFS_UINT_MAXLEN, idmap);
+ if (data_size <= 0) {
+ ret = -EINVAL;
+ } else {
+ ret = kstrtol(id_str, 10, &id_long);
+ if (!ret)
+ *id = (__u32)id_long;
+ }
+ return ret;
+}
+
+/* idmap classic begins here */
+
+enum {
+ Opt_find_uid, Opt_find_gid, Opt_find_user, Opt_find_group, Opt_find_err
+};
+
+static const match_table_t nfs_idmap_tokens = {
+ { Opt_find_uid, "uid:%s" },
+ { Opt_find_gid, "gid:%s" },
+ { Opt_find_user, "user:%s" },
+ { Opt_find_group, "group:%s" },
+ { Opt_find_err, NULL }
+};
+
+static int nfs_idmap_legacy_upcall(struct key *, void *);
+static ssize_t idmap_pipe_downcall(struct file *, const char __user *,
+ size_t);
+static void idmap_release_pipe(struct inode *);
+static void idmap_pipe_destroy_msg(struct rpc_pipe_msg *);
+
+static const struct rpc_pipe_ops idmap_upcall_ops = {
+ .upcall = rpc_pipe_generic_upcall,
+ .downcall = idmap_pipe_downcall,
+ .release_pipe = idmap_release_pipe,
+ .destroy_msg = idmap_pipe_destroy_msg,
+};
+
+static struct key_type key_type_id_resolver_legacy = {
+ .name = "id_legacy",
+ .preparse = user_preparse,
+ .free_preparse = user_free_preparse,
+ .instantiate = generic_key_instantiate,
+ .revoke = user_revoke,
+ .destroy = user_destroy,
+ .describe = user_describe,
+ .read = user_read,
+ .request_key = nfs_idmap_legacy_upcall,
+};
+
+static void nfs_idmap_pipe_destroy(struct dentry *dir,
+ struct rpc_pipe_dir_object *pdo)
+{
+ struct idmap *idmap = pdo->pdo_data;
+ struct rpc_pipe *pipe = idmap->idmap_pipe;
+
+ if (pipe->dentry) {
+ rpc_unlink(pipe->dentry);
+ pipe->dentry = NULL;
+ }
+}
+
+static int nfs_idmap_pipe_create(struct dentry *dir,
+ struct rpc_pipe_dir_object *pdo)
+{
+ struct idmap *idmap = pdo->pdo_data;
+ struct rpc_pipe *pipe = idmap->idmap_pipe;
+ struct dentry *dentry;
+
+ dentry = rpc_mkpipe_dentry(dir, "idmap", idmap, pipe);
+ if (IS_ERR(dentry))
+ return PTR_ERR(dentry);
+ pipe->dentry = dentry;
+ return 0;
+}
+
+static const struct rpc_pipe_dir_object_ops nfs_idmap_pipe_dir_object_ops = {
+ .create = nfs_idmap_pipe_create,
+ .destroy = nfs_idmap_pipe_destroy,
+};
+
+int
+nfs_idmap_new(struct nfs_client *clp)
+{
+ struct idmap *idmap;
+ struct rpc_pipe *pipe;
+ int error;
+
+ idmap = kzalloc(sizeof(*idmap), GFP_KERNEL);
+ if (idmap == NULL)
+ return -ENOMEM;
+
+ mutex_init(&idmap->idmap_mutex);
+ idmap->user_ns = get_user_ns(clp->cl_rpcclient->cl_cred->user_ns);
+
+ rpc_init_pipe_dir_object(&idmap->idmap_pdo,
+ &nfs_idmap_pipe_dir_object_ops,
+ idmap);
+
+ pipe = rpc_mkpipe_data(&idmap_upcall_ops, 0);
+ if (IS_ERR(pipe)) {
+ error = PTR_ERR(pipe);
+ goto err;
+ }
+ idmap->idmap_pipe = pipe;
+
+ error = rpc_add_pipe_dir_object(clp->cl_net,
+ &clp->cl_rpcclient->cl_pipedir_objects,
+ &idmap->idmap_pdo);
+ if (error)
+ goto err_destroy_pipe;
+
+ clp->cl_idmap = idmap;
+ return 0;
+err_destroy_pipe:
+ rpc_destroy_pipe_data(idmap->idmap_pipe);
+err:
+ put_user_ns(idmap->user_ns);
+ kfree(idmap);
+ return error;
+}
+
+void
+nfs_idmap_delete(struct nfs_client *clp)
+{
+ struct idmap *idmap = clp->cl_idmap;
+
+ if (!idmap)
+ return;
+ clp->cl_idmap = NULL;
+ rpc_remove_pipe_dir_object(clp->cl_net,
+ &clp->cl_rpcclient->cl_pipedir_objects,
+ &idmap->idmap_pdo);
+ rpc_destroy_pipe_data(idmap->idmap_pipe);
+ put_user_ns(idmap->user_ns);
+ kfree(idmap);
+}
+
+static int nfs_idmap_prepare_message(char *desc, struct idmap *idmap,
+ struct idmap_msg *im,
+ struct rpc_pipe_msg *msg)
+{
+ substring_t substr;
+ int token, ret;
+
+ im->im_type = IDMAP_TYPE_GROUP;
+ token = match_token(desc, nfs_idmap_tokens, &substr);
+
+ switch (token) {
+ case Opt_find_uid:
+ im->im_type = IDMAP_TYPE_USER;
+ fallthrough;
+ case Opt_find_gid:
+ im->im_conv = IDMAP_CONV_NAMETOID;
+ ret = match_strlcpy(im->im_name, &substr, IDMAP_NAMESZ);
+ break;
+
+ case Opt_find_user:
+ im->im_type = IDMAP_TYPE_USER;
+ fallthrough;
+ case Opt_find_group:
+ im->im_conv = IDMAP_CONV_IDTONAME;
+ ret = match_int(&substr, &im->im_id);
+ if (ret)
+ goto out;
+ break;
+
+ default:
+ ret = -EINVAL;
+ goto out;
+ }
+
+ msg->data = im;
+ msg->len = sizeof(struct idmap_msg);
+
+out:
+ return ret;
+}
+
+static bool
+nfs_idmap_prepare_pipe_upcall(struct idmap *idmap,
+ struct idmap_legacy_upcalldata *data)
+{
+ if (idmap->idmap_upcall_data != NULL) {
+ WARN_ON_ONCE(1);
+ return false;
+ }
+ idmap->idmap_upcall_data = data;
+ return true;
+}
+
+static void nfs_idmap_complete_pipe_upcall(struct idmap_legacy_upcalldata *data,
+ int ret)
+{
+ complete_request_key(data->authkey, ret);
+ key_put(data->authkey);
+ kfree(data);
+}
+
+static void nfs_idmap_abort_pipe_upcall(struct idmap *idmap,
+ struct idmap_legacy_upcalldata *data,
+ int ret)
+{
+ if (cmpxchg(&idmap->idmap_upcall_data, data, NULL) == data)
+ nfs_idmap_complete_pipe_upcall(data, ret);
+}
+
+static int nfs_idmap_legacy_upcall(struct key *authkey, void *aux)
+{
+ struct idmap_legacy_upcalldata *data;
+ struct request_key_auth *rka = get_request_key_auth(authkey);
+ struct rpc_pipe_msg *msg;
+ struct idmap_msg *im;
+ struct idmap *idmap = aux;
+ struct key *key = rka->target_key;
+ int ret = -ENOKEY;
+
+ if (!aux)
+ goto out1;
+
+ /* msg and im are freed in idmap_pipe_destroy_msg */
+ ret = -ENOMEM;
+ data = kzalloc(sizeof(*data), GFP_KERNEL);
+ if (!data)
+ goto out1;
+
+ msg = &data->pipe_msg;
+ im = &data->idmap_msg;
+ data->idmap = idmap;
+ data->authkey = key_get(authkey);
+
+ ret = nfs_idmap_prepare_message(key->description, idmap, im, msg);
+ if (ret < 0)
+ goto out2;
+
+ ret = -EAGAIN;
+ if (!nfs_idmap_prepare_pipe_upcall(idmap, data))
+ goto out2;
+
+ ret = rpc_queue_upcall(idmap->idmap_pipe, msg);
+ if (ret < 0)
+ nfs_idmap_abort_pipe_upcall(idmap, data, ret);
+
+ return ret;
+out2:
+ kfree(data);
+out1:
+ complete_request_key(authkey, ret);
+ return ret;
+}
+
+static int nfs_idmap_instantiate(struct key *key, struct key *authkey, char *data, size_t datalen)
+{
+ return key_instantiate_and_link(key, data, datalen,
+ id_resolver_cache->thread_keyring,
+ authkey);
+}
+
+static int nfs_idmap_read_and_verify_message(struct idmap_msg *im,
+ struct idmap_msg *upcall,
+ struct key *key, struct key *authkey)
+{
+ char id_str[NFS_UINT_MAXLEN];
+ size_t len;
+ int ret = -ENOKEY;
+
+ /* ret = -ENOKEY */
+ if (upcall->im_type != im->im_type || upcall->im_conv != im->im_conv)
+ goto out;
+ switch (im->im_conv) {
+ case IDMAP_CONV_NAMETOID:
+ if (strcmp(upcall->im_name, im->im_name) != 0)
+ break;
+ /* Note: here we store the NUL terminator too */
+ len = 1 + nfs_map_numeric_to_string(im->im_id, id_str,
+ sizeof(id_str));
+ ret = nfs_idmap_instantiate(key, authkey, id_str, len);
+ break;
+ case IDMAP_CONV_IDTONAME:
+ if (upcall->im_id != im->im_id)
+ break;
+ len = strlen(im->im_name);
+ ret = nfs_idmap_instantiate(key, authkey, im->im_name, len);
+ break;
+ default:
+ ret = -EINVAL;
+ }
+out:
+ return ret;
+}
+
+static ssize_t
+idmap_pipe_downcall(struct file *filp, const char __user *src, size_t mlen)
+{
+ struct request_key_auth *rka;
+ struct rpc_inode *rpci = RPC_I(file_inode(filp));
+ struct idmap *idmap = (struct idmap *)rpci->private;
+ struct idmap_legacy_upcalldata *data;
+ struct key *authkey;
+ struct idmap_msg im;
+ size_t namelen_in;
+ int ret = -ENOKEY;
+
+ /* If instantiation is successful, anyone waiting for key construction
+ * will have been woken up and someone else may now have used
+ * idmap_key_cons - so after this point we may no longer touch it.
+ */
+ data = xchg(&idmap->idmap_upcall_data, NULL);
+ if (data == NULL)
+ goto out_noupcall;
+
+ authkey = data->authkey;
+ rka = get_request_key_auth(authkey);
+
+ if (mlen != sizeof(im)) {
+ ret = -ENOSPC;
+ goto out;
+ }
+
+ if (copy_from_user(&im, src, mlen) != 0) {
+ ret = -EFAULT;
+ goto out;
+ }
+
+ if (!(im.im_status & IDMAP_STATUS_SUCCESS)) {
+ ret = -ENOKEY;
+ goto out;
+ }
+
+ namelen_in = strnlen(im.im_name, IDMAP_NAMESZ);
+ if (namelen_in == 0 || namelen_in == IDMAP_NAMESZ) {
+ ret = -EINVAL;
+ goto out;
+ }
+
+ ret = nfs_idmap_read_and_verify_message(&im, &data->idmap_msg,
+ rka->target_key, authkey);
+ if (ret >= 0) {
+ key_set_timeout(rka->target_key, nfs_idmap_cache_timeout);
+ ret = mlen;
+ }
+
+out:
+ nfs_idmap_complete_pipe_upcall(data, ret);
+out_noupcall:
+ return ret;
+}
+
+static void
+idmap_pipe_destroy_msg(struct rpc_pipe_msg *msg)
+{
+ struct idmap_legacy_upcalldata *data = container_of(msg,
+ struct idmap_legacy_upcalldata,
+ pipe_msg);
+ struct idmap *idmap = data->idmap;
+
+ if (msg->errno)
+ nfs_idmap_abort_pipe_upcall(idmap, data, msg->errno);
+}
+
+static void
+idmap_release_pipe(struct inode *inode)
+{
+ struct rpc_inode *rpci = RPC_I(inode);
+ struct idmap *idmap = (struct idmap *)rpci->private;
+ struct idmap_legacy_upcalldata *data;
+
+ data = xchg(&idmap->idmap_upcall_data, NULL);
+ if (data)
+ nfs_idmap_complete_pipe_upcall(data, -EPIPE);
+}
+
+int nfs_map_name_to_uid(const struct nfs_server *server, const char *name, size_t namelen, kuid_t *uid)
+{
+ struct idmap *idmap = server->nfs_client->cl_idmap;
+ __u32 id = -1;
+ int ret = 0;
+
+ if (!nfs_map_string_to_numeric(name, namelen, &id))
+ ret = nfs_idmap_lookup_id(name, namelen, "uid", &id, idmap);
+ if (ret == 0) {
+ *uid = make_kuid(idmap_userns(idmap), id);
+ if (!uid_valid(*uid))
+ ret = -ERANGE;
+ }
+ trace_nfs4_map_name_to_uid(name, namelen, id, ret);
+ return ret;
+}
+
+int nfs_map_group_to_gid(const struct nfs_server *server, const char *name, size_t namelen, kgid_t *gid)
+{
+ struct idmap *idmap = server->nfs_client->cl_idmap;
+ __u32 id = -1;
+ int ret = 0;
+
+ if (!nfs_map_string_to_numeric(name, namelen, &id))
+ ret = nfs_idmap_lookup_id(name, namelen, "gid", &id, idmap);
+ if (ret == 0) {
+ *gid = make_kgid(idmap_userns(idmap), id);
+ if (!gid_valid(*gid))
+ ret = -ERANGE;
+ }
+ trace_nfs4_map_group_to_gid(name, namelen, id, ret);
+ return ret;
+}
+
+int nfs_map_uid_to_name(const struct nfs_server *server, kuid_t uid, char *buf, size_t buflen)
+{
+ struct idmap *idmap = server->nfs_client->cl_idmap;
+ int ret = -EINVAL;
+ __u32 id;
+
+ id = from_kuid_munged(idmap_userns(idmap), uid);
+ if (!(server->caps & NFS_CAP_UIDGID_NOMAP))
+ ret = nfs_idmap_lookup_name(id, "user", buf, buflen, idmap);
+ if (ret < 0)
+ ret = nfs_map_numeric_to_string(id, buf, buflen);
+ trace_nfs4_map_uid_to_name(buf, ret, id, ret);
+ return ret;
+}
+int nfs_map_gid_to_group(const struct nfs_server *server, kgid_t gid, char *buf, size_t buflen)
+{
+ struct idmap *idmap = server->nfs_client->cl_idmap;
+ int ret = -EINVAL;
+ __u32 id;
+
+ id = from_kgid_munged(idmap_userns(idmap), gid);
+ if (!(server->caps & NFS_CAP_UIDGID_NOMAP))
+ ret = nfs_idmap_lookup_name(id, "group", buf, buflen, idmap);
+ if (ret < 0)
+ ret = nfs_map_numeric_to_string(id, buf, buflen);
+ trace_nfs4_map_gid_to_group(buf, ret, id, ret);
+ return ret;
+}