| /* |
| * fs/cifs/cifsacl.c |
| * |
| * Copyright (C) International Business Machines Corp., 2007,2008 |
| * Author(s): Steve French (sfrench@us.ibm.com) |
| * |
| * Contains the routines for mapping CIFS/NTFS ACLs |
| * |
| * This library is free software; you can redistribute it and/or modify |
| * it under the terms of the GNU Lesser General Public License as published |
| * by the Free Software Foundation; either version 2.1 of the License, or |
| * (at your option) any later version. |
| * |
| * This library is distributed in the hope that it will be useful, |
| * but WITHOUT ANY WARRANTY; without even the implied warranty of |
| * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See |
| * the GNU Lesser General Public License for more details. |
| * |
| * You should have received a copy of the GNU Lesser General Public License |
| * along with this library; if not, write to the Free Software |
| * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA |
| */ |
| |
| #include <linux/fs.h> |
| #include <linux/slab.h> |
| #include <linux/string.h> |
| #include <linux/keyctl.h> |
| #include <linux/key-type.h> |
| #include <keys/user-type.h> |
| #include "cifspdu.h" |
| #include "cifsglob.h" |
| #include "cifsacl.h" |
| #include "cifsproto.h" |
| #include "cifs_debug.h" |
| |
| /* security id for everyone/world system group */ |
| static const struct cifs_sid sid_everyone = { |
| 1, 1, {0, 0, 0, 0, 0, 1}, {0} }; |
| /* security id for Authenticated Users system group */ |
| static const struct cifs_sid sid_authusers = { |
| 1, 1, {0, 0, 0, 0, 0, 5}, {cpu_to_le32(11)} }; |
| /* group users */ |
| static const struct cifs_sid sid_user = {1, 2 , {0, 0, 0, 0, 0, 5}, {} }; |
| |
| const struct cred *root_cred; |
| |
| static void |
| shrink_idmap_tree(struct rb_root *root, int nr_to_scan, int *nr_rem, |
| int *nr_del) |
| { |
| struct rb_node *node; |
| struct rb_node *tmp; |
| struct cifs_sid_id *psidid; |
| |
| node = rb_first(root); |
| while (node) { |
| tmp = node; |
| node = rb_next(tmp); |
| psidid = rb_entry(tmp, struct cifs_sid_id, rbnode); |
| if (nr_to_scan == 0 || *nr_del == nr_to_scan) |
| ++(*nr_rem); |
| else { |
| if (time_after(jiffies, psidid->time + SID_MAP_EXPIRE) |
| && psidid->refcount == 0) { |
| rb_erase(tmp, root); |
| ++(*nr_del); |
| } else |
| ++(*nr_rem); |
| } |
| } |
| } |
| |
| /* |
| * Run idmap cache shrinker. |
| */ |
| static int |
| cifs_idmap_shrinker(struct shrinker *shrink, int nr_to_scan, gfp_t gfp_mask) |
| { |
| int nr_del = 0; |
| int nr_rem = 0; |
| struct rb_root *root; |
| |
| root = &uidtree; |
| spin_lock(&siduidlock); |
| shrink_idmap_tree(root, nr_to_scan, &nr_rem, &nr_del); |
| spin_unlock(&siduidlock); |
| |
| root = &gidtree; |
| spin_lock(&sidgidlock); |
| shrink_idmap_tree(root, nr_to_scan, &nr_rem, &nr_del); |
| spin_unlock(&sidgidlock); |
| |
| return nr_rem; |
| } |
| |
| static struct shrinker cifs_shrinker = { |
| .shrink = cifs_idmap_shrinker, |
| .seeks = DEFAULT_SEEKS, |
| }; |
| |
| static int |
| cifs_idmap_key_instantiate(struct key *key, const void *data, size_t datalen) |
| { |
| char *payload; |
| |
| payload = kmalloc(datalen, GFP_KERNEL); |
| if (!payload) |
| return -ENOMEM; |
| |
| memcpy(payload, data, datalen); |
| key->payload.data = payload; |
| return 0; |
| } |
| |
| static inline void |
| cifs_idmap_key_destroy(struct key *key) |
| { |
| kfree(key->payload.data); |
| } |
| |
| struct key_type cifs_idmap_key_type = { |
| .name = "cifs.idmap", |
| .instantiate = cifs_idmap_key_instantiate, |
| .destroy = cifs_idmap_key_destroy, |
| .describe = user_describe, |
| .match = user_match, |
| }; |
| |
| static void |
| sid_to_str(struct cifs_sid *sidptr, char *sidstr) |
| { |
| int i; |
| unsigned long saval; |
| char *strptr; |
| |
| strptr = sidstr; |
| |
| sprintf(strptr, "%s", "S"); |
| strptr = sidstr + strlen(sidstr); |
| |
| sprintf(strptr, "-%d", sidptr->revision); |
| strptr = sidstr + strlen(sidstr); |
| |
| for (i = 0; i < 6; ++i) { |
| if (sidptr->authority[i]) { |
| sprintf(strptr, "-%d", sidptr->authority[i]); |
| strptr = sidstr + strlen(sidstr); |
| } |
| } |
| |
| for (i = 0; i < sidptr->num_subauth; ++i) { |
| saval = le32_to_cpu(sidptr->sub_auth[i]); |
| sprintf(strptr, "-%ld", saval); |
| strptr = sidstr + strlen(sidstr); |
| } |
| } |
| |
| static void |
| id_rb_insert(struct rb_root *root, struct cifs_sid *sidptr, |
| struct cifs_sid_id **psidid, char *typestr) |
| { |
| int rc; |
| char *strptr; |
| struct rb_node *node = root->rb_node; |
| struct rb_node *parent = NULL; |
| struct rb_node **linkto = &(root->rb_node); |
| struct cifs_sid_id *lsidid; |
| |
| while (node) { |
| lsidid = rb_entry(node, struct cifs_sid_id, rbnode); |
| parent = node; |
| rc = compare_sids(sidptr, &((lsidid)->sid)); |
| if (rc > 0) { |
| linkto = &(node->rb_left); |
| node = node->rb_left; |
| } else if (rc < 0) { |
| linkto = &(node->rb_right); |
| node = node->rb_right; |
| } |
| } |
| |
| memcpy(&(*psidid)->sid, sidptr, sizeof(struct cifs_sid)); |
| (*psidid)->time = jiffies - (SID_MAP_RETRY + 1); |
| (*psidid)->refcount = 0; |
| |
| sprintf((*psidid)->sidstr, "%s", typestr); |
| strptr = (*psidid)->sidstr + strlen((*psidid)->sidstr); |
| sid_to_str(&(*psidid)->sid, strptr); |
| |
| clear_bit(SID_ID_PENDING, &(*psidid)->state); |
| clear_bit(SID_ID_MAPPED, &(*psidid)->state); |
| |
| rb_link_node(&(*psidid)->rbnode, parent, linkto); |
| rb_insert_color(&(*psidid)->rbnode, root); |
| } |
| |
| static struct cifs_sid_id * |
| id_rb_search(struct rb_root *root, struct cifs_sid *sidptr) |
| { |
| int rc; |
| struct rb_node *node = root->rb_node; |
| struct cifs_sid_id *lsidid; |
| |
| while (node) { |
| lsidid = rb_entry(node, struct cifs_sid_id, rbnode); |
| rc = compare_sids(sidptr, &((lsidid)->sid)); |
| if (rc > 0) { |
| node = node->rb_left; |
| } else if (rc < 0) { |
| node = node->rb_right; |
| } else /* node found */ |
| return lsidid; |
| } |
| |
| return NULL; |
| } |
| |
| static int |
| sidid_pending_wait(void *unused) |
| { |
| schedule(); |
| return signal_pending(current) ? -ERESTARTSYS : 0; |
| } |
| |
| static int |
| sid_to_id(struct cifs_sb_info *cifs_sb, struct cifs_sid *psid, |
| struct cifs_fattr *fattr, uint sidtype) |
| { |
| int rc; |
| unsigned long cid; |
| struct key *idkey; |
| const struct cred *saved_cred; |
| struct cifs_sid_id *psidid, *npsidid; |
| struct rb_root *cidtree; |
| spinlock_t *cidlock; |
| |
| if (sidtype == SIDOWNER) { |
| cid = cifs_sb->mnt_uid; /* default uid, in case upcall fails */ |
| cidlock = &siduidlock; |
| cidtree = &uidtree; |
| } else if (sidtype == SIDGROUP) { |
| cid = cifs_sb->mnt_gid; /* default gid, in case upcall fails */ |
| cidlock = &sidgidlock; |
| cidtree = &gidtree; |
| } else |
| return -ENOENT; |
| |
| spin_lock(cidlock); |
| psidid = id_rb_search(cidtree, psid); |
| |
| if (!psidid) { /* node does not exist, allocate one & attempt adding */ |
| spin_unlock(cidlock); |
| npsidid = kzalloc(sizeof(struct cifs_sid_id), GFP_KERNEL); |
| if (!npsidid) |
| return -ENOMEM; |
| |
| npsidid->sidstr = kmalloc(SIDLEN, GFP_KERNEL); |
| if (!npsidid->sidstr) { |
| kfree(npsidid); |
| return -ENOMEM; |
| } |
| |
| spin_lock(cidlock); |
| psidid = id_rb_search(cidtree, psid); |
| if (psidid) { /* node happened to get inserted meanwhile */ |
| ++psidid->refcount; |
| spin_unlock(cidlock); |
| kfree(npsidid->sidstr); |
| kfree(npsidid); |
| } else { |
| psidid = npsidid; |
| id_rb_insert(cidtree, psid, &psidid, |
| sidtype == SIDOWNER ? "os:" : "gs:"); |
| ++psidid->refcount; |
| spin_unlock(cidlock); |
| } |
| } else { |
| ++psidid->refcount; |
| spin_unlock(cidlock); |
| } |
| |
| /* |
| * If we are here, it is safe to access psidid and its fields |
| * since a reference was taken earlier while holding the spinlock. |
| * A reference on the node is put without holding the spinlock |
| * and it is OK to do so in this case, shrinker will not erase |
| * this node until all references are put and we do not access |
| * any fields of the node after a reference is put . |
| */ |
| if (test_bit(SID_ID_MAPPED, &psidid->state)) { |
| cid = psidid->id; |
| psidid->time = jiffies; /* update ts for accessing */ |
| goto sid_to_id_out; |
| } |
| |
| if (time_after(psidid->time + SID_MAP_RETRY, jiffies)) |
| goto sid_to_id_out; |
| |
| if (!test_and_set_bit(SID_ID_PENDING, &psidid->state)) { |
| saved_cred = override_creds(root_cred); |
| idkey = request_key(&cifs_idmap_key_type, psidid->sidstr, ""); |
| if (IS_ERR(idkey)) |
| cFYI(1, "%s: Can't map SID to an id", __func__); |
| else { |
| cid = *(unsigned long *)idkey->payload.value; |
| psidid->id = cid; |
| set_bit(SID_ID_MAPPED, &psidid->state); |
| key_put(idkey); |
| kfree(psidid->sidstr); |
| } |
| revert_creds(saved_cred); |
| psidid->time = jiffies; /* update ts for accessing */ |
| clear_bit(SID_ID_PENDING, &psidid->state); |
| wake_up_bit(&psidid->state, SID_ID_PENDING); |
| } else { |
| rc = wait_on_bit(&psidid->state, SID_ID_PENDING, |
| sidid_pending_wait, TASK_INTERRUPTIBLE); |
| if (rc) { |
| cFYI(1, "%s: sidid_pending_wait interrupted %d", |
| __func__, rc); |
| --psidid->refcount; /* decremented without spinlock */ |
| return rc; |
| } |
| if (test_bit(SID_ID_MAPPED, &psidid->state)) |
| cid = psidid->id; |
| } |
| |
| sid_to_id_out: |
| --psidid->refcount; /* decremented without spinlock */ |
| if (sidtype == SIDOWNER) |
| fattr->cf_uid = cid; |
| else |
| fattr->cf_gid = cid; |
| |
| return 0; |
| } |
| |
| int |
| init_cifs_idmap(void) |
| { |
| struct cred *cred; |
| struct key *keyring; |
| int ret; |
| |
| cFYI(1, "Registering the %s key type\n", cifs_idmap_key_type.name); |
| |
| /* create an override credential set with a special thread keyring in |
| * which requests are cached |
| * |
| * this is used to prevent malicious redirections from being installed |
| * with add_key(). |
| */ |
| cred = prepare_kernel_cred(NULL); |
| if (!cred) |
| return -ENOMEM; |
| |
| keyring = key_alloc(&key_type_keyring, ".cifs_idmap", 0, 0, cred, |
| (KEY_POS_ALL & ~KEY_POS_SETATTR) | |
| KEY_USR_VIEW | KEY_USR_READ, |
| KEY_ALLOC_NOT_IN_QUOTA); |
| if (IS_ERR(keyring)) { |
| ret = PTR_ERR(keyring); |
| goto failed_put_cred; |
| } |
| |
| ret = key_instantiate_and_link(keyring, NULL, 0, NULL, NULL); |
| if (ret < 0) |
| goto failed_put_key; |
| |
| ret = register_key_type(&cifs_idmap_key_type); |
| if (ret < 0) |
| goto failed_put_key; |
| |
| /* instruct request_key() to use this special keyring as a cache for |
| * the results it looks up */ |
| cred->thread_keyring = keyring; |
| cred->jit_keyring = KEY_REQKEY_DEFL_THREAD_KEYRING; |
| root_cred = cred; |
| |
| spin_lock_init(&siduidlock); |
| uidtree = RB_ROOT; |
| spin_lock_init(&sidgidlock); |
| gidtree = RB_ROOT; |
| |
| register_shrinker(&cifs_shrinker); |
| |
| cFYI(1, "cifs idmap keyring: %d\n", key_serial(keyring)); |
| return 0; |
| |
| failed_put_key: |
| key_put(keyring); |
| failed_put_cred: |
| put_cred(cred); |
| return ret; |
| } |
| |
| void |
| exit_cifs_idmap(void) |
| { |
| key_revoke(root_cred->thread_keyring); |
| unregister_key_type(&cifs_idmap_key_type); |
| put_cred(root_cred); |
| unregister_shrinker(&cifs_shrinker); |
| cFYI(1, "Unregistered %s key type\n", cifs_idmap_key_type.name); |
| } |
| |
| void |
| cifs_destroy_idmaptrees(void) |
| { |
| struct rb_root *root; |
| struct rb_node *node; |
| |
| root = &uidtree; |
| spin_lock(&siduidlock); |
| while ((node = rb_first(root))) |
| rb_erase(node, root); |
| spin_unlock(&siduidlock); |
| |
| root = &gidtree; |
| spin_lock(&sidgidlock); |
| while ((node = rb_first(root))) |
| rb_erase(node, root); |
| spin_unlock(&sidgidlock); |
| } |
| |
| /* if the two SIDs (roughly equivalent to a UUID for a user or group) are |
| the same returns 1, if they do not match returns 0 */ |
| int compare_sids(const struct cifs_sid *ctsid, const struct cifs_sid *cwsid) |
| { |
| int i; |
| int num_subauth, num_sat, num_saw; |
| |
| if ((!ctsid) || (!cwsid)) |
| return 1; |
| |
| /* compare the revision */ |
| if (ctsid->revision != cwsid->revision) { |
| if (ctsid->revision > cwsid->revision) |
| return 1; |
| else |
| return -1; |
| } |
| |
| /* compare all of the six auth values */ |
| for (i = 0; i < 6; ++i) { |
| if (ctsid->authority[i] != cwsid->authority[i]) { |
| if (ctsid->authority[i] > cwsid->authority[i]) |
| return 1; |
| else |
| return -1; |
| } |
| } |
| |
| /* compare all of the subauth values if any */ |
| num_sat = ctsid->num_subauth; |
| num_saw = cwsid->num_subauth; |
| num_subauth = num_sat < num_saw ? num_sat : num_saw; |
| if (num_subauth) { |
| for (i = 0; i < num_subauth; ++i) { |
| if (ctsid->sub_auth[i] != cwsid->sub_auth[i]) { |
| if (le32_to_cpu(ctsid->sub_auth[i]) > |
| le32_to_cpu(cwsid->sub_auth[i])) |
| return 1; |
| else |
| return -1; |
| } |
| } |
| } |
| |
| return 0; /* sids compare/match */ |
| } |
| |
| |
| /* copy ntsd, owner sid, and group sid from a security descriptor to another */ |
| static void copy_sec_desc(const struct cifs_ntsd *pntsd, |
| struct cifs_ntsd *pnntsd, __u32 sidsoffset) |
| { |
| int i; |
| |
| struct cifs_sid *owner_sid_ptr, *group_sid_ptr; |
| struct cifs_sid *nowner_sid_ptr, *ngroup_sid_ptr; |
| |
| /* copy security descriptor control portion */ |
| pnntsd->revision = pntsd->revision; |
| pnntsd->type = pntsd->type; |
| pnntsd->dacloffset = cpu_to_le32(sizeof(struct cifs_ntsd)); |
| pnntsd->sacloffset = 0; |
| pnntsd->osidoffset = cpu_to_le32(sidsoffset); |
| pnntsd->gsidoffset = cpu_to_le32(sidsoffset + sizeof(struct cifs_sid)); |
| |
| /* copy owner sid */ |
| owner_sid_ptr = (struct cifs_sid *)((char *)pntsd + |
| le32_to_cpu(pntsd->osidoffset)); |
| nowner_sid_ptr = (struct cifs_sid *)((char *)pnntsd + sidsoffset); |
| |
| nowner_sid_ptr->revision = owner_sid_ptr->revision; |
| nowner_sid_ptr->num_subauth = owner_sid_ptr->num_subauth; |
| for (i = 0; i < 6; i++) |
| nowner_sid_ptr->authority[i] = owner_sid_ptr->authority[i]; |
| for (i = 0; i < 5; i++) |
| nowner_sid_ptr->sub_auth[i] = owner_sid_ptr->sub_auth[i]; |
| |
| /* copy group sid */ |
| group_sid_ptr = (struct cifs_sid *)((char *)pntsd + |
| le32_to_cpu(pntsd->gsidoffset)); |
| ngroup_sid_ptr = (struct cifs_sid *)((char *)pnntsd + sidsoffset + |
| sizeof(struct cifs_sid)); |
| |
| ngroup_sid_ptr->revision = group_sid_ptr->revision; |
| ngroup_sid_ptr->num_subauth = group_sid_ptr->num_subauth; |
| for (i = 0; i < 6; i++) |
| ngroup_sid_ptr->authority[i] = group_sid_ptr->authority[i]; |
| for (i = 0; i < 5; i++) |
| ngroup_sid_ptr->sub_auth[i] = group_sid_ptr->sub_auth[i]; |
| |
| return; |
| } |
| |
| |
| /* |
| change posix mode to reflect permissions |
| pmode is the existing mode (we only want to overwrite part of this |
| bits to set can be: S_IRWXU, S_IRWXG or S_IRWXO ie 00700 or 00070 or 00007 |
| */ |
| static void access_flags_to_mode(__le32 ace_flags, int type, umode_t *pmode, |
| umode_t *pbits_to_set) |
| { |
| __u32 flags = le32_to_cpu(ace_flags); |
| /* the order of ACEs is important. The canonical order is to begin with |
| DENY entries followed by ALLOW, otherwise an allow entry could be |
| encountered first, making the subsequent deny entry like "dead code" |
| which would be superflous since Windows stops when a match is made |
| for the operation you are trying to perform for your user */ |
| |
| /* For deny ACEs we change the mask so that subsequent allow access |
| control entries do not turn on the bits we are denying */ |
| if (type == ACCESS_DENIED) { |
| if (flags & GENERIC_ALL) |
| *pbits_to_set &= ~S_IRWXUGO; |
| |
| if ((flags & GENERIC_WRITE) || |
| ((flags & FILE_WRITE_RIGHTS) == FILE_WRITE_RIGHTS)) |
| *pbits_to_set &= ~S_IWUGO; |
| if ((flags & GENERIC_READ) || |
| ((flags & FILE_READ_RIGHTS) == FILE_READ_RIGHTS)) |
| *pbits_to_set &= ~S_IRUGO; |
| if ((flags & GENERIC_EXECUTE) || |
| ((flags & FILE_EXEC_RIGHTS) == FILE_EXEC_RIGHTS)) |
| *pbits_to_set &= ~S_IXUGO; |
| return; |
| } else if (type != ACCESS_ALLOWED) { |
| cERROR(1, "unknown access control type %d", type); |
| return; |
| } |
| /* else ACCESS_ALLOWED type */ |
| |
| if (flags & GENERIC_ALL) { |
| *pmode |= (S_IRWXUGO & (*pbits_to_set)); |
| cFYI(DBG2, "all perms"); |
| return; |
| } |
| if ((flags & GENERIC_WRITE) || |
| ((flags & FILE_WRITE_RIGHTS) == FILE_WRITE_RIGHTS)) |
| *pmode |= (S_IWUGO & (*pbits_to_set)); |
| if ((flags & GENERIC_READ) || |
| ((flags & FILE_READ_RIGHTS) == FILE_READ_RIGHTS)) |
| *pmode |= (S_IRUGO & (*pbits_to_set)); |
| if ((flags & GENERIC_EXECUTE) || |
| ((flags & FILE_EXEC_RIGHTS) == FILE_EXEC_RIGHTS)) |
| *pmode |= (S_IXUGO & (*pbits_to_set)); |
| |
| cFYI(DBG2, "access flags 0x%x mode now 0x%x", flags, *pmode); |
| return; |
| } |
| |
| /* |
| Generate access flags to reflect permissions mode is the existing mode. |
| This function is called for every ACE in the DACL whose SID matches |
| with either owner or group or everyone. |
| */ |
| |
| static void mode_to_access_flags(umode_t mode, umode_t bits_to_use, |
| __u32 *pace_flags) |
| { |
| /* reset access mask */ |
| *pace_flags = 0x0; |
| |
| /* bits to use are either S_IRWXU or S_IRWXG or S_IRWXO */ |
| mode &= bits_to_use; |
| |
| /* check for R/W/X UGO since we do not know whose flags |
| is this but we have cleared all the bits sans RWX for |
| either user or group or other as per bits_to_use */ |
| if (mode & S_IRUGO) |
| *pace_flags |= SET_FILE_READ_RIGHTS; |
| if (mode & S_IWUGO) |
| *pace_flags |= SET_FILE_WRITE_RIGHTS; |
| if (mode & S_IXUGO) |
| *pace_flags |= SET_FILE_EXEC_RIGHTS; |
| |
| cFYI(DBG2, "mode: 0x%x, access flags now 0x%x", mode, *pace_flags); |
| return; |
| } |
| |
| static __u16 fill_ace_for_sid(struct cifs_ace *pntace, |
| const struct cifs_sid *psid, __u64 nmode, umode_t bits) |
| { |
| int i; |
| __u16 size = 0; |
| __u32 access_req = 0; |
| |
| pntace->type = ACCESS_ALLOWED; |
| pntace->flags = 0x0; |
| mode_to_access_flags(nmode, bits, &access_req); |
| if (!access_req) |
| access_req = SET_MINIMUM_RIGHTS; |
| pntace->access_req = cpu_to_le32(access_req); |
| |
| pntace->sid.revision = psid->revision; |
| pntace->sid.num_subauth = psid->num_subauth; |
| for (i = 0; i < 6; i++) |
| pntace->sid.authority[i] = psid->authority[i]; |
| for (i = 0; i < psid->num_subauth; i++) |
| pntace->sid.sub_auth[i] = psid->sub_auth[i]; |
| |
| size = 1 + 1 + 2 + 4 + 1 + 1 + 6 + (psid->num_subauth * 4); |
| pntace->size = cpu_to_le16(size); |
| |
| return size; |
| } |
| |
| |
| #ifdef CONFIG_CIFS_DEBUG2 |
| static void dump_ace(struct cifs_ace *pace, char *end_of_acl) |
| { |
| int num_subauth; |
| |
| /* validate that we do not go past end of acl */ |
| |
| if (le16_to_cpu(pace->size) < 16) { |
| cERROR(1, "ACE too small %d", le16_to_cpu(pace->size)); |
| return; |
| } |
| |
| if (end_of_acl < (char *)pace + le16_to_cpu(pace->size)) { |
| cERROR(1, "ACL too small to parse ACE"); |
| return; |
| } |
| |
| num_subauth = pace->sid.num_subauth; |
| if (num_subauth) { |
| int i; |
| cFYI(1, "ACE revision %d num_auth %d type %d flags %d size %d", |
| pace->sid.revision, pace->sid.num_subauth, pace->type, |
| pace->flags, le16_to_cpu(pace->size)); |
| for (i = 0; i < num_subauth; ++i) { |
| cFYI(1, "ACE sub_auth[%d]: 0x%x", i, |
| le32_to_cpu(pace->sid.sub_auth[i])); |
| } |
| |
| /* BB add length check to make sure that we do not have huge |
| num auths and therefore go off the end */ |
| } |
| |
| return; |
| } |
| #endif |
| |
| |
| static void parse_dacl(struct cifs_acl *pdacl, char *end_of_acl, |
| struct cifs_sid *pownersid, struct cifs_sid *pgrpsid, |
| struct cifs_fattr *fattr) |
| { |
| int i; |
| int num_aces = 0; |
| int acl_size; |
| char *acl_base; |
| struct cifs_ace **ppace; |
| |
| /* BB need to add parm so we can store the SID BB */ |
| |
| if (!pdacl) { |
| /* no DACL in the security descriptor, set |
| all the permissions for user/group/other */ |
| fattr->cf_mode |= S_IRWXUGO; |
| return; |
| } |
| |
| /* validate that we do not go past end of acl */ |
| if (end_of_acl < (char *)pdacl + le16_to_cpu(pdacl->size)) { |
| cERROR(1, "ACL too small to parse DACL"); |
| return; |
| } |
| |
| cFYI(DBG2, "DACL revision %d size %d num aces %d", |
| le16_to_cpu(pdacl->revision), le16_to_cpu(pdacl->size), |
| le32_to_cpu(pdacl->num_aces)); |
| |
| /* reset rwx permissions for user/group/other. |
| Also, if num_aces is 0 i.e. DACL has no ACEs, |
| user/group/other have no permissions */ |
| fattr->cf_mode &= ~(S_IRWXUGO); |
| |
| acl_base = (char *)pdacl; |
| acl_size = sizeof(struct cifs_acl); |
| |
| num_aces = le32_to_cpu(pdacl->num_aces); |
| if (num_aces > 0) { |
| umode_t user_mask = S_IRWXU; |
| umode_t group_mask = S_IRWXG; |
| umode_t other_mask = S_IRWXU | S_IRWXG | S_IRWXO; |
| |
| ppace = kmalloc(num_aces * sizeof(struct cifs_ace *), |
| GFP_KERNEL); |
| if (!ppace) { |
| cERROR(1, "DACL memory allocation error"); |
| return; |
| } |
| |
| for (i = 0; i < num_aces; ++i) { |
| ppace[i] = (struct cifs_ace *) (acl_base + acl_size); |
| #ifdef CONFIG_CIFS_DEBUG2 |
| dump_ace(ppace[i], end_of_acl); |
| #endif |
| if (compare_sids(&(ppace[i]->sid), pownersid) == 0) |
| access_flags_to_mode(ppace[i]->access_req, |
| ppace[i]->type, |
| &fattr->cf_mode, |
| &user_mask); |
| if (compare_sids(&(ppace[i]->sid), pgrpsid) == 0) |
| access_flags_to_mode(ppace[i]->access_req, |
| ppace[i]->type, |
| &fattr->cf_mode, |
| &group_mask); |
| if (compare_sids(&(ppace[i]->sid), &sid_everyone) == 0) |
| access_flags_to_mode(ppace[i]->access_req, |
| ppace[i]->type, |
| &fattr->cf_mode, |
| &other_mask); |
| if (compare_sids(&(ppace[i]->sid), &sid_authusers) == 0) |
| access_flags_to_mode(ppace[i]->access_req, |
| ppace[i]->type, |
| &fattr->cf_mode, |
| &other_mask); |
| |
| |
| /* memcpy((void *)(&(cifscred->aces[i])), |
| (void *)ppace[i], |
| sizeof(struct cifs_ace)); */ |
| |
| acl_base = (char *)ppace[i]; |
| acl_size = le16_to_cpu(ppace[i]->size); |
| } |
| |
| kfree(ppace); |
| } |
| |
| return; |
| } |
| |
| |
| static int set_chmod_dacl(struct cifs_acl *pndacl, struct cifs_sid *pownersid, |
| struct cifs_sid *pgrpsid, __u64 nmode) |
| { |
| u16 size = 0; |
| struct cifs_acl *pnndacl; |
| |
| pnndacl = (struct cifs_acl *)((char *)pndacl + sizeof(struct cifs_acl)); |
| |
| size += fill_ace_for_sid((struct cifs_ace *) ((char *)pnndacl + size), |
| pownersid, nmode, S_IRWXU); |
| size += fill_ace_for_sid((struct cifs_ace *)((char *)pnndacl + size), |
| pgrpsid, nmode, S_IRWXG); |
| size += fill_ace_for_sid((struct cifs_ace *)((char *)pnndacl + size), |
| &sid_everyone, nmode, S_IRWXO); |
| |
| pndacl->size = cpu_to_le16(size + sizeof(struct cifs_acl)); |
| pndacl->num_aces = cpu_to_le32(3); |
| |
| return 0; |
| } |
| |
| |
| static int parse_sid(struct cifs_sid *psid, char *end_of_acl) |
| { |
| /* BB need to add parm so we can store the SID BB */ |
| |
| /* validate that we do not go past end of ACL - sid must be at least 8 |
| bytes long (assuming no sub-auths - e.g. the null SID */ |
| if (end_of_acl < (char *)psid + 8) { |
| cERROR(1, "ACL too small to parse SID %p", psid); |
| return -EINVAL; |
| } |
| |
| if (psid->num_subauth) { |
| #ifdef CONFIG_CIFS_DEBUG2 |
| int i; |
| cFYI(1, "SID revision %d num_auth %d", |
| psid->revision, psid->num_subauth); |
| |
| for (i = 0; i < psid->num_subauth; i++) { |
| cFYI(1, "SID sub_auth[%d]: 0x%x ", i, |
| le32_to_cpu(psid->sub_auth[i])); |
| } |
| |
| /* BB add length check to make sure that we do not have huge |
| num auths and therefore go off the end */ |
| cFYI(1, "RID 0x%x", |
| le32_to_cpu(psid->sub_auth[psid->num_subauth-1])); |
| #endif |
| } |
| |
| return 0; |
| } |
| |
| |
| /* Convert CIFS ACL to POSIX form */ |
| static int parse_sec_desc(struct cifs_sb_info *cifs_sb, |
| struct cifs_ntsd *pntsd, int acl_len, struct cifs_fattr *fattr) |
| { |
| int rc = 0; |
| struct cifs_sid *owner_sid_ptr, *group_sid_ptr; |
| struct cifs_acl *dacl_ptr; /* no need for SACL ptr */ |
| char *end_of_acl = ((char *)pntsd) + acl_len; |
| __u32 dacloffset; |
| |
| if (pntsd == NULL) |
| return -EIO; |
| |
| owner_sid_ptr = (struct cifs_sid *)((char *)pntsd + |
| le32_to_cpu(pntsd->osidoffset)); |
| group_sid_ptr = (struct cifs_sid *)((char *)pntsd + |
| le32_to_cpu(pntsd->gsidoffset)); |
| dacloffset = le32_to_cpu(pntsd->dacloffset); |
| dacl_ptr = (struct cifs_acl *)((char *)pntsd + dacloffset); |
| cFYI(DBG2, "revision %d type 0x%x ooffset 0x%x goffset 0x%x " |
| "sacloffset 0x%x dacloffset 0x%x", |
| pntsd->revision, pntsd->type, le32_to_cpu(pntsd->osidoffset), |
| le32_to_cpu(pntsd->gsidoffset), |
| le32_to_cpu(pntsd->sacloffset), dacloffset); |
| /* cifs_dump_mem("owner_sid: ", owner_sid_ptr, 64); */ |
| rc = parse_sid(owner_sid_ptr, end_of_acl); |
| if (rc) { |
| cFYI(1, "%s: Error %d parsing Owner SID", __func__, rc); |
| return rc; |
| } |
| rc = sid_to_id(cifs_sb, owner_sid_ptr, fattr, SIDOWNER); |
| if (rc) { |
| cFYI(1, "%s: Error %d mapping Owner SID to uid", __func__, rc); |
| return rc; |
| } |
| |
| rc = parse_sid(group_sid_ptr, end_of_acl); |
| if (rc) { |
| cFYI(1, "%s: Error %d mapping Owner SID to gid", __func__, rc); |
| return rc; |
| } |
| rc = sid_to_id(cifs_sb, group_sid_ptr, fattr, SIDGROUP); |
| if (rc) { |
| cFYI(1, "%s: Error %d mapping Group SID to gid", __func__, rc); |
| return rc; |
| } |
| |
| if (dacloffset) |
| parse_dacl(dacl_ptr, end_of_acl, owner_sid_ptr, |
| group_sid_ptr, fattr); |
| else |
| cFYI(1, "no ACL"); /* BB grant all or default perms? */ |
| |
| /* cifscred->uid = owner_sid_ptr->rid; |
| cifscred->gid = group_sid_ptr->rid; |
| memcpy((void *)(&(cifscred->osid)), (void *)owner_sid_ptr, |
| sizeof(struct cifs_sid)); |
| memcpy((void *)(&(cifscred->gsid)), (void *)group_sid_ptr, |
| sizeof(struct cifs_sid)); */ |
| |
| return rc; |
| } |
| |
| |
| /* Convert permission bits from mode to equivalent CIFS ACL */ |
| static int build_sec_desc(struct cifs_ntsd *pntsd, struct cifs_ntsd *pnntsd, |
| struct inode *inode, __u64 nmode) |
| { |
| int rc = 0; |
| __u32 dacloffset; |
| __u32 ndacloffset; |
| __u32 sidsoffset; |
| struct cifs_sid *owner_sid_ptr, *group_sid_ptr; |
| struct cifs_acl *dacl_ptr = NULL; /* no need for SACL ptr */ |
| struct cifs_acl *ndacl_ptr = NULL; /* no need for SACL ptr */ |
| |
| if ((inode == NULL) || (pntsd == NULL) || (pnntsd == NULL)) |
| return -EIO; |
| |
| owner_sid_ptr = (struct cifs_sid *)((char *)pntsd + |
| le32_to_cpu(pntsd->osidoffset)); |
| group_sid_ptr = (struct cifs_sid *)((char *)pntsd + |
| le32_to_cpu(pntsd->gsidoffset)); |
| |
| dacloffset = le32_to_cpu(pntsd->dacloffset); |
| dacl_ptr = (struct cifs_acl *)((char *)pntsd + dacloffset); |
| |
| ndacloffset = sizeof(struct cifs_ntsd); |
| ndacl_ptr = (struct cifs_acl *)((char *)pnntsd + ndacloffset); |
| ndacl_ptr->revision = dacl_ptr->revision; |
| ndacl_ptr->size = 0; |
| ndacl_ptr->num_aces = 0; |
| |
| rc = set_chmod_dacl(ndacl_ptr, owner_sid_ptr, group_sid_ptr, nmode); |
| |
| sidsoffset = ndacloffset + le16_to_cpu(ndacl_ptr->size); |
| |
| /* copy security descriptor control portion and owner and group sid */ |
| copy_sec_desc(pntsd, pnntsd, sidsoffset); |
| |
| return rc; |
| } |
| |
| static struct cifs_ntsd *get_cifs_acl_by_fid(struct cifs_sb_info *cifs_sb, |
| __u16 fid, u32 *pacllen) |
| { |
| struct cifs_ntsd *pntsd = NULL; |
| int xid, rc; |
| struct tcon_link *tlink = cifs_sb_tlink(cifs_sb); |
| |
| if (IS_ERR(tlink)) |
| return ERR_CAST(tlink); |
| |
| xid = GetXid(); |
| rc = CIFSSMBGetCIFSACL(xid, tlink_tcon(tlink), fid, &pntsd, pacllen); |
| FreeXid(xid); |
| |
| cifs_put_tlink(tlink); |
| |
| cFYI(1, "%s: rc = %d ACL len %d", __func__, rc, *pacllen); |
| if (rc) |
| return ERR_PTR(rc); |
| return pntsd; |
| } |
| |
| static struct cifs_ntsd *get_cifs_acl_by_path(struct cifs_sb_info *cifs_sb, |
| const char *path, u32 *pacllen) |
| { |
| struct cifs_ntsd *pntsd = NULL; |
| int oplock = 0; |
| int xid, rc; |
| __u16 fid; |
| struct cifs_tcon *tcon; |
| struct tcon_link *tlink = cifs_sb_tlink(cifs_sb); |
| |
| if (IS_ERR(tlink)) |
| return ERR_CAST(tlink); |
| |
| tcon = tlink_tcon(tlink); |
| xid = GetXid(); |
| |
| rc = CIFSSMBOpen(xid, tcon, path, FILE_OPEN, READ_CONTROL, 0, |
| &fid, &oplock, NULL, cifs_sb->local_nls, |
| cifs_sb->mnt_cifs_flags & CIFS_MOUNT_MAP_SPECIAL_CHR); |
| if (!rc) { |
| rc = CIFSSMBGetCIFSACL(xid, tcon, fid, &pntsd, pacllen); |
| CIFSSMBClose(xid, tcon, fid); |
| } |
| |
| cifs_put_tlink(tlink); |
| FreeXid(xid); |
| |
| cFYI(1, "%s: rc = %d ACL len %d", __func__, rc, *pacllen); |
| if (rc) |
| return ERR_PTR(rc); |
| return pntsd; |
| } |
| |
| /* Retrieve an ACL from the server */ |
| struct cifs_ntsd *get_cifs_acl(struct cifs_sb_info *cifs_sb, |
| struct inode *inode, const char *path, |
| u32 *pacllen) |
| { |
| struct cifs_ntsd *pntsd = NULL; |
| struct cifsFileInfo *open_file = NULL; |
| |
| if (inode) |
| open_file = find_readable_file(CIFS_I(inode), true); |
| if (!open_file) |
| return get_cifs_acl_by_path(cifs_sb, path, pacllen); |
| |
| pntsd = get_cifs_acl_by_fid(cifs_sb, open_file->netfid, pacllen); |
| cifsFileInfo_put(open_file); |
| return pntsd; |
| } |
| |
| static int set_cifs_acl_by_fid(struct cifs_sb_info *cifs_sb, __u16 fid, |
| struct cifs_ntsd *pnntsd, u32 acllen) |
| { |
| int xid, rc; |
| struct tcon_link *tlink = cifs_sb_tlink(cifs_sb); |
| |
| if (IS_ERR(tlink)) |
| return PTR_ERR(tlink); |
| |
| xid = GetXid(); |
| rc = CIFSSMBSetCIFSACL(xid, tlink_tcon(tlink), fid, pnntsd, acllen); |
| FreeXid(xid); |
| cifs_put_tlink(tlink); |
| |
| cFYI(DBG2, "SetCIFSACL rc = %d", rc); |
| return rc; |
| } |
| |
| static int set_cifs_acl_by_path(struct cifs_sb_info *cifs_sb, const char *path, |
| struct cifs_ntsd *pnntsd, u32 acllen) |
| { |
| int oplock = 0; |
| int xid, rc; |
| __u16 fid; |
| struct cifs_tcon *tcon; |
| struct tcon_link *tlink = cifs_sb_tlink(cifs_sb); |
| |
| if (IS_ERR(tlink)) |
| return PTR_ERR(tlink); |
| |
| tcon = tlink_tcon(tlink); |
| xid = GetXid(); |
| |
| rc = CIFSSMBOpen(xid, tcon, path, FILE_OPEN, WRITE_DAC, 0, |
| &fid, &oplock, NULL, cifs_sb->local_nls, |
| cifs_sb->mnt_cifs_flags & CIFS_MOUNT_MAP_SPECIAL_CHR); |
| if (rc) { |
| cERROR(1, "Unable to open file to set ACL"); |
| goto out; |
| } |
| |
| rc = CIFSSMBSetCIFSACL(xid, tcon, fid, pnntsd, acllen); |
| cFYI(DBG2, "SetCIFSACL rc = %d", rc); |
| |
| CIFSSMBClose(xid, tcon, fid); |
| out: |
| FreeXid(xid); |
| cifs_put_tlink(tlink); |
| return rc; |
| } |
| |
| /* Set an ACL on the server */ |
| int set_cifs_acl(struct cifs_ntsd *pnntsd, __u32 acllen, |
| struct inode *inode, const char *path) |
| { |
| struct cifs_sb_info *cifs_sb = CIFS_SB(inode->i_sb); |
| struct cifsFileInfo *open_file; |
| int rc; |
| |
| cFYI(DBG2, "set ACL for %s from mode 0x%x", path, inode->i_mode); |
| |
| open_file = find_readable_file(CIFS_I(inode), true); |
| if (!open_file) |
| return set_cifs_acl_by_path(cifs_sb, path, pnntsd, acllen); |
| |
| rc = set_cifs_acl_by_fid(cifs_sb, open_file->netfid, pnntsd, acllen); |
| cifsFileInfo_put(open_file); |
| return rc; |
| } |
| |
| /* Translate the CIFS ACL (simlar to NTFS ACL) for a file into mode bits */ |
| int |
| cifs_acl_to_fattr(struct cifs_sb_info *cifs_sb, struct cifs_fattr *fattr, |
| struct inode *inode, const char *path, const __u16 *pfid) |
| { |
| struct cifs_ntsd *pntsd = NULL; |
| u32 acllen = 0; |
| int rc = 0; |
| |
| cFYI(DBG2, "converting ACL to mode for %s", path); |
| |
| if (pfid) |
| pntsd = get_cifs_acl_by_fid(cifs_sb, *pfid, &acllen); |
| else |
| pntsd = get_cifs_acl(cifs_sb, inode, path, &acllen); |
| |
| /* if we can retrieve the ACL, now parse Access Control Entries, ACEs */ |
| if (IS_ERR(pntsd)) { |
| rc = PTR_ERR(pntsd); |
| cERROR(1, "%s: error %d getting sec desc", __func__, rc); |
| } else { |
| rc = parse_sec_desc(cifs_sb, pntsd, acllen, fattr); |
| kfree(pntsd); |
| if (rc) |
| cERROR(1, "parse sec desc failed rc = %d", rc); |
| } |
| |
| return rc; |
| } |
| |
| /* Convert mode bits to an ACL so we can update the ACL on the server */ |
| int mode_to_cifs_acl(struct inode *inode, const char *path, __u64 nmode) |
| { |
| int rc = 0; |
| __u32 secdesclen = 0; |
| struct cifs_ntsd *pntsd = NULL; /* acl obtained from server */ |
| struct cifs_ntsd *pnntsd = NULL; /* modified acl to be sent to server */ |
| |
| cFYI(DBG2, "set ACL from mode for %s", path); |
| |
| /* Get the security descriptor */ |
| pntsd = get_cifs_acl(CIFS_SB(inode->i_sb), inode, path, &secdesclen); |
| |
| /* Add three ACEs for owner, group, everyone getting rid of |
| other ACEs as chmod disables ACEs and set the security descriptor */ |
| |
| if (IS_ERR(pntsd)) { |
| rc = PTR_ERR(pntsd); |
| cERROR(1, "%s: error %d getting sec desc", __func__, rc); |
| } else { |
| /* allocate memory for the smb header, |
| set security descriptor request security descriptor |
| parameters, and secuirty descriptor itself */ |
| |
| secdesclen = secdesclen < DEFSECDESCLEN ? |
| DEFSECDESCLEN : secdesclen; |
| pnntsd = kmalloc(secdesclen, GFP_KERNEL); |
| if (!pnntsd) { |
| cERROR(1, "Unable to allocate security descriptor"); |
| kfree(pntsd); |
| return -ENOMEM; |
| } |
| |
| rc = build_sec_desc(pntsd, pnntsd, inode, nmode); |
| |
| cFYI(DBG2, "build_sec_desc rc: %d", rc); |
| |
| if (!rc) { |
| /* Set the security descriptor */ |
| rc = set_cifs_acl(pnntsd, secdesclen, inode, path); |
| cFYI(DBG2, "set_cifs_acl rc: %d", rc); |
| } |
| |
| kfree(pnntsd); |
| kfree(pntsd); |
| } |
| |
| return rc; |
| } |