v4.19.13 snapshot.
diff --git a/fs/nfsd/nfs4idmap.c b/fs/nfsd/nfs4idmap.c
new file mode 100644
index 0000000..a5bb765
--- /dev/null
+++ b/fs/nfsd/nfs4idmap.c
@@ -0,0 +1,671 @@
+/*
+ * Mapping of UID/GIDs to name and vice versa.
+ *
+ * Copyright (c) 2002, 2003 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/module.h>
+#include <linux/seq_file.h>
+#include <linux/sched.h>
+#include <linux/slab.h>
+#include <linux/sunrpc/svc_xprt.h>
+#include <net/net_namespace.h>
+#include "idmap.h"
+#include "nfsd.h"
+#include "netns.h"
+
+/*
+ * Turn off idmapping when using AUTH_SYS.
+ */
+static bool nfs4_disable_idmapping = true;
+module_param(nfs4_disable_idmapping, bool, 0644);
+MODULE_PARM_DESC(nfs4_disable_idmapping,
+ "Turn off server's NFSv4 idmapping when using 'sec=sys'");
+
+/*
+ * Cache entry
+ */
+
+/*
+ * XXX we know that IDMAP_NAMESZ < PAGE_SIZE, but it's ugly to rely on
+ * that.
+ */
+
+struct ent {
+ struct cache_head h;
+ int type; /* User / Group */
+ u32 id;
+ char name[IDMAP_NAMESZ];
+ char authname[IDMAP_NAMESZ];
+};
+
+/* Common entry handling */
+
+#define ENT_HASHBITS 8
+#define ENT_HASHMAX (1 << ENT_HASHBITS)
+
+static void
+ent_init(struct cache_head *cnew, struct cache_head *citm)
+{
+ struct ent *new = container_of(cnew, struct ent, h);
+ struct ent *itm = container_of(citm, struct ent, h);
+
+ new->id = itm->id;
+ new->type = itm->type;
+
+ strlcpy(new->name, itm->name, sizeof(new->name));
+ strlcpy(new->authname, itm->authname, sizeof(new->name));
+}
+
+static void
+ent_put(struct kref *ref)
+{
+ struct ent *map = container_of(ref, struct ent, h.ref);
+ kfree(map);
+}
+
+static struct cache_head *
+ent_alloc(void)
+{
+ struct ent *e = kmalloc(sizeof(*e), GFP_KERNEL);
+ if (e)
+ return &e->h;
+ else
+ return NULL;
+}
+
+/*
+ * ID -> Name cache
+ */
+
+static uint32_t
+idtoname_hash(struct ent *ent)
+{
+ uint32_t hash;
+
+ hash = hash_str(ent->authname, ENT_HASHBITS);
+ hash = hash_long(hash ^ ent->id, ENT_HASHBITS);
+
+ /* Flip LSB for user/group */
+ if (ent->type == IDMAP_TYPE_GROUP)
+ hash ^= 1;
+
+ return hash;
+}
+
+static void
+idtoname_request(struct cache_detail *cd, struct cache_head *ch, char **bpp,
+ int *blen)
+{
+ struct ent *ent = container_of(ch, struct ent, h);
+ char idstr[11];
+
+ qword_add(bpp, blen, ent->authname);
+ snprintf(idstr, sizeof(idstr), "%u", ent->id);
+ qword_add(bpp, blen, ent->type == IDMAP_TYPE_GROUP ? "group" : "user");
+ qword_add(bpp, blen, idstr);
+
+ (*bpp)[-1] = '\n';
+}
+
+static int
+idtoname_match(struct cache_head *ca, struct cache_head *cb)
+{
+ struct ent *a = container_of(ca, struct ent, h);
+ struct ent *b = container_of(cb, struct ent, h);
+
+ return (a->id == b->id && a->type == b->type &&
+ strcmp(a->authname, b->authname) == 0);
+}
+
+static int
+idtoname_show(struct seq_file *m, struct cache_detail *cd, struct cache_head *h)
+{
+ struct ent *ent;
+
+ if (h == NULL) {
+ seq_puts(m, "#domain type id [name]\n");
+ return 0;
+ }
+ ent = container_of(h, struct ent, h);
+ seq_printf(m, "%s %s %u", ent->authname,
+ ent->type == IDMAP_TYPE_GROUP ? "group" : "user",
+ ent->id);
+ if (test_bit(CACHE_VALID, &h->flags))
+ seq_printf(m, " %s", ent->name);
+ seq_printf(m, "\n");
+ return 0;
+}
+
+static void
+warn_no_idmapd(struct cache_detail *detail, int has_died)
+{
+ printk("nfsd: nfsv4 idmapping failing: has idmapd %s?\n",
+ has_died ? "died" : "not been started");
+}
+
+
+static int idtoname_parse(struct cache_detail *, char *, int);
+static struct ent *idtoname_lookup(struct cache_detail *, struct ent *);
+static struct ent *idtoname_update(struct cache_detail *, struct ent *,
+ struct ent *);
+
+static const struct cache_detail idtoname_cache_template = {
+ .owner = THIS_MODULE,
+ .hash_size = ENT_HASHMAX,
+ .name = "nfs4.idtoname",
+ .cache_put = ent_put,
+ .cache_request = idtoname_request,
+ .cache_parse = idtoname_parse,
+ .cache_show = idtoname_show,
+ .warn_no_listener = warn_no_idmapd,
+ .match = idtoname_match,
+ .init = ent_init,
+ .update = ent_init,
+ .alloc = ent_alloc,
+};
+
+static int
+idtoname_parse(struct cache_detail *cd, char *buf, int buflen)
+{
+ struct ent ent, *res;
+ char *buf1, *bp;
+ int len;
+ int error = -EINVAL;
+
+ if (buf[buflen - 1] != '\n')
+ return (-EINVAL);
+ buf[buflen - 1]= '\0';
+
+ buf1 = kmalloc(PAGE_SIZE, GFP_KERNEL);
+ if (buf1 == NULL)
+ return (-ENOMEM);
+
+ memset(&ent, 0, sizeof(ent));
+
+ /* Authentication name */
+ len = qword_get(&buf, buf1, PAGE_SIZE);
+ if (len <= 0 || len >= IDMAP_NAMESZ)
+ goto out;
+ memcpy(ent.authname, buf1, sizeof(ent.authname));
+
+ /* Type */
+ if (qword_get(&buf, buf1, PAGE_SIZE) <= 0)
+ goto out;
+ ent.type = strcmp(buf1, "user") == 0 ?
+ IDMAP_TYPE_USER : IDMAP_TYPE_GROUP;
+
+ /* ID */
+ if (qword_get(&buf, buf1, PAGE_SIZE) <= 0)
+ goto out;
+ ent.id = simple_strtoul(buf1, &bp, 10);
+ if (bp == buf1)
+ goto out;
+
+ /* expiry */
+ ent.h.expiry_time = get_expiry(&buf);
+ if (ent.h.expiry_time == 0)
+ goto out;
+
+ error = -ENOMEM;
+ res = idtoname_lookup(cd, &ent);
+ if (!res)
+ goto out;
+
+ /* Name */
+ error = -EINVAL;
+ len = qword_get(&buf, buf1, PAGE_SIZE);
+ if (len < 0 || len >= IDMAP_NAMESZ)
+ goto out;
+ if (len == 0)
+ set_bit(CACHE_NEGATIVE, &ent.h.flags);
+ else
+ memcpy(ent.name, buf1, sizeof(ent.name));
+ error = -ENOMEM;
+ res = idtoname_update(cd, &ent, res);
+ if (res == NULL)
+ goto out;
+
+ cache_put(&res->h, cd);
+ error = 0;
+out:
+ kfree(buf1);
+ return error;
+}
+
+static struct ent *
+idtoname_lookup(struct cache_detail *cd, struct ent *item)
+{
+ struct cache_head *ch = sunrpc_cache_lookup(cd, &item->h,
+ idtoname_hash(item));
+ if (ch)
+ return container_of(ch, struct ent, h);
+ else
+ return NULL;
+}
+
+static struct ent *
+idtoname_update(struct cache_detail *cd, struct ent *new, struct ent *old)
+{
+ struct cache_head *ch = sunrpc_cache_update(cd, &new->h, &old->h,
+ idtoname_hash(new));
+ if (ch)
+ return container_of(ch, struct ent, h);
+ else
+ return NULL;
+}
+
+
+/*
+ * Name -> ID cache
+ */
+
+static inline int
+nametoid_hash(struct ent *ent)
+{
+ return hash_str(ent->name, ENT_HASHBITS);
+}
+
+static void
+nametoid_request(struct cache_detail *cd, struct cache_head *ch, char **bpp,
+ int *blen)
+{
+ struct ent *ent = container_of(ch, struct ent, h);
+
+ qword_add(bpp, blen, ent->authname);
+ qword_add(bpp, blen, ent->type == IDMAP_TYPE_GROUP ? "group" : "user");
+ qword_add(bpp, blen, ent->name);
+
+ (*bpp)[-1] = '\n';
+}
+
+static int
+nametoid_match(struct cache_head *ca, struct cache_head *cb)
+{
+ struct ent *a = container_of(ca, struct ent, h);
+ struct ent *b = container_of(cb, struct ent, h);
+
+ return (a->type == b->type && strcmp(a->name, b->name) == 0 &&
+ strcmp(a->authname, b->authname) == 0);
+}
+
+static int
+nametoid_show(struct seq_file *m, struct cache_detail *cd, struct cache_head *h)
+{
+ struct ent *ent;
+
+ if (h == NULL) {
+ seq_puts(m, "#domain type name [id]\n");
+ return 0;
+ }
+ ent = container_of(h, struct ent, h);
+ seq_printf(m, "%s %s %s", ent->authname,
+ ent->type == IDMAP_TYPE_GROUP ? "group" : "user",
+ ent->name);
+ if (test_bit(CACHE_VALID, &h->flags))
+ seq_printf(m, " %u", ent->id);
+ seq_printf(m, "\n");
+ return 0;
+}
+
+static struct ent *nametoid_lookup(struct cache_detail *, struct ent *);
+static struct ent *nametoid_update(struct cache_detail *, struct ent *,
+ struct ent *);
+static int nametoid_parse(struct cache_detail *, char *, int);
+
+static const struct cache_detail nametoid_cache_template = {
+ .owner = THIS_MODULE,
+ .hash_size = ENT_HASHMAX,
+ .name = "nfs4.nametoid",
+ .cache_put = ent_put,
+ .cache_request = nametoid_request,
+ .cache_parse = nametoid_parse,
+ .cache_show = nametoid_show,
+ .warn_no_listener = warn_no_idmapd,
+ .match = nametoid_match,
+ .init = ent_init,
+ .update = ent_init,
+ .alloc = ent_alloc,
+};
+
+static int
+nametoid_parse(struct cache_detail *cd, char *buf, int buflen)
+{
+ struct ent ent, *res;
+ char *buf1;
+ int len, error = -EINVAL;
+
+ if (buf[buflen - 1] != '\n')
+ return (-EINVAL);
+ buf[buflen - 1]= '\0';
+
+ buf1 = kmalloc(PAGE_SIZE, GFP_KERNEL);
+ if (buf1 == NULL)
+ return (-ENOMEM);
+
+ memset(&ent, 0, sizeof(ent));
+
+ /* Authentication name */
+ len = qword_get(&buf, buf1, PAGE_SIZE);
+ if (len <= 0 || len >= IDMAP_NAMESZ)
+ goto out;
+ memcpy(ent.authname, buf1, sizeof(ent.authname));
+
+ /* Type */
+ if (qword_get(&buf, buf1, PAGE_SIZE) <= 0)
+ goto out;
+ ent.type = strcmp(buf1, "user") == 0 ?
+ IDMAP_TYPE_USER : IDMAP_TYPE_GROUP;
+
+ /* Name */
+ len = qword_get(&buf, buf1, PAGE_SIZE);
+ if (len <= 0 || len >= IDMAP_NAMESZ)
+ goto out;
+ memcpy(ent.name, buf1, sizeof(ent.name));
+
+ /* expiry */
+ ent.h.expiry_time = get_expiry(&buf);
+ if (ent.h.expiry_time == 0)
+ goto out;
+
+ /* ID */
+ error = get_int(&buf, &ent.id);
+ if (error == -EINVAL)
+ goto out;
+ if (error == -ENOENT)
+ set_bit(CACHE_NEGATIVE, &ent.h.flags);
+
+ error = -ENOMEM;
+ res = nametoid_lookup(cd, &ent);
+ if (res == NULL)
+ goto out;
+ res = nametoid_update(cd, &ent, res);
+ if (res == NULL)
+ goto out;
+
+ cache_put(&res->h, cd);
+ error = 0;
+out:
+ kfree(buf1);
+ return (error);
+}
+
+
+static struct ent *
+nametoid_lookup(struct cache_detail *cd, struct ent *item)
+{
+ struct cache_head *ch = sunrpc_cache_lookup(cd, &item->h,
+ nametoid_hash(item));
+ if (ch)
+ return container_of(ch, struct ent, h);
+ else
+ return NULL;
+}
+
+static struct ent *
+nametoid_update(struct cache_detail *cd, struct ent *new, struct ent *old)
+{
+ struct cache_head *ch = sunrpc_cache_update(cd, &new->h, &old->h,
+ nametoid_hash(new));
+ if (ch)
+ return container_of(ch, struct ent, h);
+ else
+ return NULL;
+}
+
+/*
+ * Exported API
+ */
+
+int
+nfsd_idmap_init(struct net *net)
+{
+ int rv;
+ struct nfsd_net *nn = net_generic(net, nfsd_net_id);
+
+ nn->idtoname_cache = cache_create_net(&idtoname_cache_template, net);
+ if (IS_ERR(nn->idtoname_cache))
+ return PTR_ERR(nn->idtoname_cache);
+ rv = cache_register_net(nn->idtoname_cache, net);
+ if (rv)
+ goto destroy_idtoname_cache;
+ nn->nametoid_cache = cache_create_net(&nametoid_cache_template, net);
+ if (IS_ERR(nn->nametoid_cache)) {
+ rv = PTR_ERR(nn->nametoid_cache);
+ goto unregister_idtoname_cache;
+ }
+ rv = cache_register_net(nn->nametoid_cache, net);
+ if (rv)
+ goto destroy_nametoid_cache;
+ return 0;
+
+destroy_nametoid_cache:
+ cache_destroy_net(nn->nametoid_cache, net);
+unregister_idtoname_cache:
+ cache_unregister_net(nn->idtoname_cache, net);
+destroy_idtoname_cache:
+ cache_destroy_net(nn->idtoname_cache, net);
+ return rv;
+}
+
+void
+nfsd_idmap_shutdown(struct net *net)
+{
+ struct nfsd_net *nn = net_generic(net, nfsd_net_id);
+
+ cache_unregister_net(nn->idtoname_cache, net);
+ cache_unregister_net(nn->nametoid_cache, net);
+ cache_destroy_net(nn->idtoname_cache, net);
+ cache_destroy_net(nn->nametoid_cache, net);
+}
+
+static int
+idmap_lookup(struct svc_rqst *rqstp,
+ struct ent *(*lookup_fn)(struct cache_detail *, struct ent *),
+ struct ent *key, struct cache_detail *detail, struct ent **item)
+{
+ int ret;
+
+ *item = lookup_fn(detail, key);
+ if (!*item)
+ return -ENOMEM;
+ retry:
+ ret = cache_check(detail, &(*item)->h, &rqstp->rq_chandle);
+
+ if (ret == -ETIMEDOUT) {
+ struct ent *prev_item = *item;
+ *item = lookup_fn(detail, key);
+ if (*item != prev_item)
+ goto retry;
+ cache_put(&(*item)->h, detail);
+ }
+ return ret;
+}
+
+static char *
+rqst_authname(struct svc_rqst *rqstp)
+{
+ struct auth_domain *clp;
+
+ clp = rqstp->rq_gssclient ? rqstp->rq_gssclient : rqstp->rq_client;
+ return clp->name;
+}
+
+static __be32
+idmap_name_to_id(struct svc_rqst *rqstp, int type, const char *name, u32 namelen,
+ u32 *id)
+{
+ struct ent *item, key = {
+ .type = type,
+ };
+ int ret;
+ struct nfsd_net *nn = net_generic(SVC_NET(rqstp), nfsd_net_id);
+
+ if (namelen + 1 > sizeof(key.name))
+ return nfserr_badowner;
+ memcpy(key.name, name, namelen);
+ key.name[namelen] = '\0';
+ strlcpy(key.authname, rqst_authname(rqstp), sizeof(key.authname));
+ ret = idmap_lookup(rqstp, nametoid_lookup, &key, nn->nametoid_cache, &item);
+ if (ret == -ENOENT)
+ return nfserr_badowner;
+ if (ret)
+ return nfserrno(ret);
+ *id = item->id;
+ cache_put(&item->h, nn->nametoid_cache);
+ return 0;
+}
+
+static __be32 encode_ascii_id(struct xdr_stream *xdr, u32 id)
+{
+ char buf[11];
+ int len;
+ __be32 *p;
+
+ len = sprintf(buf, "%u", id);
+ p = xdr_reserve_space(xdr, len + 4);
+ if (!p)
+ return nfserr_resource;
+ p = xdr_encode_opaque(p, buf, len);
+ return 0;
+}
+
+static __be32 idmap_id_to_name(struct xdr_stream *xdr,
+ struct svc_rqst *rqstp, int type, u32 id)
+{
+ struct ent *item, key = {
+ .id = id,
+ .type = type,
+ };
+ __be32 *p;
+ int ret;
+ struct nfsd_net *nn = net_generic(SVC_NET(rqstp), nfsd_net_id);
+
+ strlcpy(key.authname, rqst_authname(rqstp), sizeof(key.authname));
+ ret = idmap_lookup(rqstp, idtoname_lookup, &key, nn->idtoname_cache, &item);
+ if (ret == -ENOENT)
+ return encode_ascii_id(xdr, id);
+ if (ret)
+ return nfserrno(ret);
+ ret = strlen(item->name);
+ WARN_ON_ONCE(ret > IDMAP_NAMESZ);
+ p = xdr_reserve_space(xdr, ret + 4);
+ if (!p)
+ return nfserr_resource;
+ p = xdr_encode_opaque(p, item->name, ret);
+ cache_put(&item->h, nn->idtoname_cache);
+ return 0;
+}
+
+static bool
+numeric_name_to_id(struct svc_rqst *rqstp, int type, const char *name, u32 namelen, u32 *id)
+{
+ int ret;
+ char buf[11];
+
+ if (namelen + 1 > sizeof(buf))
+ /* too long to represent a 32-bit id: */
+ return false;
+ /* Just to make sure it's null-terminated: */
+ memcpy(buf, name, namelen);
+ buf[namelen] = '\0';
+ ret = kstrtouint(buf, 10, id);
+ return ret == 0;
+}
+
+static __be32
+do_name_to_id(struct svc_rqst *rqstp, int type, const char *name, u32 namelen, u32 *id)
+{
+ if (nfs4_disable_idmapping && rqstp->rq_cred.cr_flavor < RPC_AUTH_GSS)
+ if (numeric_name_to_id(rqstp, type, name, namelen, id))
+ return 0;
+ /*
+ * otherwise, fall through and try idmapping, for
+ * backwards compatibility with clients sending names:
+ */
+ return idmap_name_to_id(rqstp, type, name, namelen, id);
+}
+
+static __be32 encode_name_from_id(struct xdr_stream *xdr,
+ struct svc_rqst *rqstp, int type, u32 id)
+{
+ if (nfs4_disable_idmapping && rqstp->rq_cred.cr_flavor < RPC_AUTH_GSS)
+ return encode_ascii_id(xdr, id);
+ return idmap_id_to_name(xdr, rqstp, type, id);
+}
+
+__be32
+nfsd_map_name_to_uid(struct svc_rqst *rqstp, const char *name, size_t namelen,
+ kuid_t *uid)
+{
+ __be32 status;
+ u32 id = -1;
+
+ if (name == NULL || namelen == 0)
+ return nfserr_inval;
+
+ status = do_name_to_id(rqstp, IDMAP_TYPE_USER, name, namelen, &id);
+ *uid = make_kuid(&init_user_ns, id);
+ if (!uid_valid(*uid))
+ status = nfserr_badowner;
+ return status;
+}
+
+__be32
+nfsd_map_name_to_gid(struct svc_rqst *rqstp, const char *name, size_t namelen,
+ kgid_t *gid)
+{
+ __be32 status;
+ u32 id = -1;
+
+ if (name == NULL || namelen == 0)
+ return nfserr_inval;
+
+ status = do_name_to_id(rqstp, IDMAP_TYPE_GROUP, name, namelen, &id);
+ *gid = make_kgid(&init_user_ns, id);
+ if (!gid_valid(*gid))
+ status = nfserr_badowner;
+ return status;
+}
+
+__be32 nfsd4_encode_user(struct xdr_stream *xdr, struct svc_rqst *rqstp,
+ kuid_t uid)
+{
+ u32 id = from_kuid(&init_user_ns, uid);
+ return encode_name_from_id(xdr, rqstp, IDMAP_TYPE_USER, id);
+}
+
+__be32 nfsd4_encode_group(struct xdr_stream *xdr, struct svc_rqst *rqstp,
+ kgid_t gid)
+{
+ u32 id = from_kgid(&init_user_ns, gid);
+ return encode_name_from_id(xdr, rqstp, IDMAP_TYPE_GROUP, id);
+}