diff options
Diffstat (limited to 'fs/nfsd/nfs4idmap.c')
-rw-r--r-- | fs/nfsd/nfs4idmap.c | 588 |
1 files changed, 588 insertions, 0 deletions
diff --git a/fs/nfsd/nfs4idmap.c b/fs/nfsd/nfs4idmap.c new file mode 100644 index 0000000..4ba5408 --- /dev/null +++ b/fs/nfsd/nfs4idmap.c @@ -0,0 +1,588 @@ +/* + * fs/nfsd/nfs4idmap.c + * + * 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/config.h> +#include <linux/module.h> +#include <linux/init.h> + +#include <linux/mm.h> +#include <linux/utsname.h> +#include <linux/errno.h> +#include <linux/string.h> +#include <linux/sunrpc/clnt.h> +#include <linux/nfs.h> +#include <linux/nfs4.h> +#include <linux/nfs_fs.h> +#include <linux/nfs_page.h> +#include <linux/smp_lock.h> +#include <linux/sunrpc/cache.h> +#include <linux/nfsd_idmap.h> +#include <linux/list.h> +#include <linux/sched.h> +#include <linux/time.h> +#include <linux/seq_file.h> +#include <linux/sunrpc/svcauth.h> + +/* + * Cache entry + */ + +/* + * XXX we know that IDMAP_NAMESZ < PAGE_SIZE, but it's ugly to rely on + * that. + */ + +#define IDMAP_TYPE_USER 0 +#define IDMAP_TYPE_GROUP 1 + +struct ent { + struct cache_head h; + int type; /* User / Group */ + uid_t id; + char name[IDMAP_NAMESZ]; + char authname[IDMAP_NAMESZ]; +}; + +#define DefineSimpleCacheLookupMap(STRUCT, FUNC) \ + DefineCacheLookup(struct STRUCT, h, FUNC##_lookup, \ + (struct STRUCT *item, int set), /*no setup */, \ + & FUNC##_cache, FUNC##_hash(item), FUNC##_match(item, tmp), \ + STRUCT##_init(new, item), STRUCT##_update(tmp, item), 0) + +/* Common entry handling */ + +#define ENT_HASHBITS 8 +#define ENT_HASHMAX (1 << ENT_HASHBITS) +#define ENT_HASHMASK (ENT_HASHMAX - 1) + +static inline void +ent_init(struct ent *new, struct ent *itm) +{ + 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 inline void +ent_update(struct ent *new, struct ent *itm) +{ + ent_init(new, itm); +} + +void +ent_put(struct cache_head *ch, struct cache_detail *cd) +{ + if (cache_put(ch, cd)) { + struct ent *map = container_of(ch, struct ent, h); + kfree(map); + } +} + +/* + * ID -> Name cache + */ + +static struct cache_head *idtoname_table[ENT_HASHMAX]; + +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), "%d", ent->id); + qword_add(bpp, blen, ent->type == IDMAP_TYPE_GROUP ? "group" : "user"); + qword_add(bpp, blen, idstr); + + (*bpp)[-1] = '\n'; +} + +static inline int +idtoname_match(struct ent *a, struct ent *b) +{ + 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 %d", 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) +{ + printk("nfsd: nfsv4 idmapping failing: has idmapd %s?\n", + detail->last_close? "died" : "not been started"); +} + + +static int idtoname_parse(struct cache_detail *, char *, int); +static struct ent *idtoname_lookup(struct ent *, int); + +struct cache_detail idtoname_cache = { + .hash_size = ENT_HASHMAX, + .hash_table = idtoname_table, + .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, +}; + +int +idtoname_parse(struct cache_detail *cd, char *buf, int buflen) +{ + struct ent ent, *res; + char *buf1, *bp; + 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 */ + if (qword_get(&buf, buf1, PAGE_SIZE) <= 0) + 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; + + /* Name */ + error = qword_get(&buf, buf1, PAGE_SIZE); + if (error == -EINVAL) + goto out; + if (error == -ENOENT) + set_bit(CACHE_NEGATIVE, &ent.h.flags); + else { + if (error >= IDMAP_NAMESZ) { + error = -EINVAL; + goto out; + } + memcpy(ent.name, buf1, sizeof(ent.name)); + } + error = -ENOMEM; + if ((res = idtoname_lookup(&ent, 1)) == NULL) + goto out; + + ent_put(&res->h, &idtoname_cache); + + error = 0; +out: + kfree(buf1); + + return error; +} + +static DefineSimpleCacheLookupMap(ent, idtoname); + +/* + * Name -> ID cache + */ + +static struct cache_head *nametoid_table[ENT_HASHMAX]; + +static inline int +nametoid_hash(struct ent *ent) +{ + return hash_str(ent->name, ENT_HASHBITS); +} + +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 inline int +nametoid_match(struct ent *a, struct ent *b) +{ + 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, " %d", ent->id); + seq_printf(m, "\n"); + return 0; +} + +static struct ent *nametoid_lookup(struct ent *, int); +int nametoid_parse(struct cache_detail *, char *, int); + +struct cache_detail nametoid_cache = { + .hash_size = ENT_HASHMAX, + .hash_table = nametoid_table, + .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, +}; + +int +nametoid_parse(struct cache_detail *cd, char *buf, int buflen) +{ + struct ent ent, *res; + char *buf1; + 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 */ + if (qword_get(&buf, buf1, PAGE_SIZE) <= 0) + 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 */ + error = qword_get(&buf, buf1, PAGE_SIZE); + if (error <= 0 || error >= 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; + if ((res = nametoid_lookup(&ent, 1)) == NULL) + goto out; + + ent_put(&res->h, &nametoid_cache); + error = 0; +out: + kfree(buf1); + + return (error); +} + +static DefineSimpleCacheLookupMap(ent, nametoid); + +/* + * Exported API + */ + +void +nfsd_idmap_init(void) +{ + cache_register(&idtoname_cache); + cache_register(&nametoid_cache); +} + +void +nfsd_idmap_shutdown(void) +{ + cache_unregister(&idtoname_cache); + cache_unregister(&nametoid_cache); +} + +/* + * Deferred request handling + */ + +struct idmap_defer_req { + struct cache_req req; + struct cache_deferred_req deferred_req; + wait_queue_head_t waitq; + atomic_t count; +}; + +static inline void +put_mdr(struct idmap_defer_req *mdr) +{ + if (atomic_dec_and_test(&mdr->count)) + kfree(mdr); +} + +static inline void +get_mdr(struct idmap_defer_req *mdr) +{ + atomic_inc(&mdr->count); +} + +static void +idmap_revisit(struct cache_deferred_req *dreq, int toomany) +{ + struct idmap_defer_req *mdr = + container_of(dreq, struct idmap_defer_req, deferred_req); + + wake_up(&mdr->waitq); + put_mdr(mdr); +} + +static struct cache_deferred_req * +idmap_defer(struct cache_req *req) +{ + struct idmap_defer_req *mdr = + container_of(req, struct idmap_defer_req, req); + + mdr->deferred_req.revisit = idmap_revisit; + get_mdr(mdr); + return (&mdr->deferred_req); +} + +static inline int +do_idmap_lookup(struct ent *(*lookup_fn)(struct ent *, int), struct ent *key, + struct cache_detail *detail, struct ent **item, + struct idmap_defer_req *mdr) +{ + *item = lookup_fn(key, 0); + if (!*item) + return -ENOMEM; + return cache_check(detail, &(*item)->h, &mdr->req); +} + +static inline int +do_idmap_lookup_nowait(struct ent *(*lookup_fn)(struct ent *, int), + struct ent *key, struct cache_detail *detail, + struct ent **item) +{ + int ret = -ENOMEM; + + *item = lookup_fn(key, 0); + if (!*item) + goto out_err; + ret = -ETIMEDOUT; + if (!test_bit(CACHE_VALID, &(*item)->h.flags) + || (*item)->h.expiry_time < get_seconds() + || detail->flush_time > (*item)->h.last_refresh) + goto out_put; + ret = -ENOENT; + if (test_bit(CACHE_NEGATIVE, &(*item)->h.flags)) + goto out_put; + return 0; +out_put: + ent_put(&(*item)->h, detail); +out_err: + *item = NULL; + return ret; +} + +static int +idmap_lookup(struct svc_rqst *rqstp, + struct ent *(*lookup_fn)(struct ent *, int), struct ent *key, + struct cache_detail *detail, struct ent **item) +{ + struct idmap_defer_req *mdr; + int ret; + + mdr = kmalloc(sizeof(*mdr), GFP_KERNEL); + if (!mdr) + return -ENOMEM; + memset(mdr, 0, sizeof(*mdr)); + atomic_set(&mdr->count, 1); + init_waitqueue_head(&mdr->waitq); + mdr->req.defer = idmap_defer; + ret = do_idmap_lookup(lookup_fn, key, detail, item, mdr); + if (ret == -EAGAIN) { + wait_event_interruptible_timeout(mdr->waitq, + test_bit(CACHE_VALID, &(*item)->h.flags), 1 * HZ); + ret = do_idmap_lookup_nowait(lookup_fn, key, detail, item); + } + put_mdr(mdr); + return ret; +} + +static int +idmap_name_to_id(struct svc_rqst *rqstp, int type, const char *name, u32 namelen, + uid_t *id) +{ + struct ent *item, key = { + .type = type, + }; + int ret; + + if (namelen + 1 > sizeof(key.name)) + return -EINVAL; + memcpy(key.name, name, namelen); + key.name[namelen] = '\0'; + strlcpy(key.authname, rqstp->rq_client->name, sizeof(key.authname)); + ret = idmap_lookup(rqstp, nametoid_lookup, &key, &nametoid_cache, &item); + if (ret == -ENOENT) + ret = -ESRCH; /* nfserr_badname */ + if (ret) + return ret; + *id = item->id; + ent_put(&item->h, &nametoid_cache); + return 0; +} + +static int +idmap_id_to_name(struct svc_rqst *rqstp, int type, uid_t id, char *name) +{ + struct ent *item, key = { + .id = id, + .type = type, + }; + int ret; + + strlcpy(key.authname, rqstp->rq_client->name, sizeof(key.authname)); + ret = idmap_lookup(rqstp, idtoname_lookup, &key, &idtoname_cache, &item); + if (ret == -ENOENT) + return sprintf(name, "%u", id); + if (ret) + return ret; + ret = strlen(item->name); + BUG_ON(ret > IDMAP_NAMESZ); + memcpy(name, item->name, ret); + ent_put(&item->h, &idtoname_cache); + return ret; +} + +int +nfsd_map_name_to_uid(struct svc_rqst *rqstp, const char *name, size_t namelen, + __u32 *id) +{ + return idmap_name_to_id(rqstp, IDMAP_TYPE_USER, name, namelen, id); +} + +int +nfsd_map_name_to_gid(struct svc_rqst *rqstp, const char *name, size_t namelen, + __u32 *id) +{ + return idmap_name_to_id(rqstp, IDMAP_TYPE_GROUP, name, namelen, id); +} + +int +nfsd_map_uid_to_name(struct svc_rqst *rqstp, __u32 id, char *name) +{ + return idmap_id_to_name(rqstp, IDMAP_TYPE_USER, id, name); +} + +int +nfsd_map_gid_to_name(struct svc_rqst *rqstp, __u32 id, char *name) +{ + return idmap_id_to_name(rqstp, IDMAP_TYPE_GROUP, id, name); +} |