diff options
Diffstat (limited to 'fs/cifs/cifsacl.c')
| -rw-r--r-- | fs/cifs/cifsacl.c | 1069 |
1 files changed, 0 insertions, 1069 deletions
diff --git a/fs/cifs/cifsacl.c b/fs/cifs/cifsacl.c deleted file mode 100644 index 51f5e0ee7237..000000000000 --- a/fs/cifs/cifsacl.c +++ /dev/null @@ -1,1069 +0,0 @@ -/* - * 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}, {__constant_cpu_to_le32(11)} }; -/* group users */ -static const struct cifs_sid sid_user = {1, 2 , {0, 0, 0, 0, 0, 5}, {} }; - -static const struct cred *root_cred; - -static int -cifs_idmap_key_instantiate(struct key *key, struct key_preparsed_payload *prep) -{ - char *payload; - - /* - * If the payload is less than or equal to the size of a pointer, then - * an allocation here is wasteful. Just copy the data directly to the - * payload.value union member instead. - * - * With this however, you must check the datalen before trying to - * dereference payload.data! - */ - if (prep->datalen <= sizeof(key->payload)) { - key->payload.value = 0; - memcpy(&key->payload.value, prep->data, prep->datalen); - key->datalen = prep->datalen; - return 0; - } - payload = kmemdup(prep->data, prep->datalen, GFP_KERNEL); - if (!payload) - return -ENOMEM; - - key->payload.data = payload; - key->datalen = prep->datalen; - return 0; -} - -static inline void -cifs_idmap_key_destroy(struct key *key) -{ - if (key->datalen > sizeof(key->payload)) - kfree(key->payload.data); -} - -static 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 char * -sid_to_key_str(struct cifs_sid *sidptr, unsigned int type) -{ - int i, len; - unsigned int saval; - char *sidstr, *strptr; - unsigned long long id_auth_val; - - /* 3 bytes for prefix */ - sidstr = kmalloc(3 + SID_STRING_BASE_SIZE + - (SID_STRING_SUBAUTH_SIZE * sidptr->num_subauth), - GFP_KERNEL); - if (!sidstr) - return sidstr; - - strptr = sidstr; - len = sprintf(strptr, "%cs:S-%hhu", type == SIDOWNER ? 'o' : 'g', - sidptr->revision); - strptr += len; - - /* The authority field is a single 48-bit number */ - id_auth_val = (unsigned long long)sidptr->authority[5]; - id_auth_val |= (unsigned long long)sidptr->authority[4] << 8; - id_auth_val |= (unsigned long long)sidptr->authority[3] << 16; - id_auth_val |= (unsigned long long)sidptr->authority[2] << 24; - id_auth_val |= (unsigned long long)sidptr->authority[1] << 32; - id_auth_val |= (unsigned long long)sidptr->authority[0] << 48; - - /* - * MS-DTYP states that if the authority is >= 2^32, then it should be - * expressed as a hex value. - */ - if (id_auth_val <= UINT_MAX) - len = sprintf(strptr, "-%llu", id_auth_val); - else - len = sprintf(strptr, "-0x%llx", id_auth_val); - - strptr += len; - - for (i = 0; i < sidptr->num_subauth; ++i) { - saval = le32_to_cpu(sidptr->sub_auth[i]); - len = sprintf(strptr, "-%u", saval); - strptr += len; - } - - return sidstr; -} - -/* - * if the two SIDs (roughly equivalent to a UUID for a user or group) are - * the same returns zero, if they do not match returns non-zero. - */ -static 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 < NUM_AUTHS; ++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 */ -} - -static void -cifs_copy_sid(struct cifs_sid *dst, const struct cifs_sid *src) -{ - int i; - - dst->revision = src->revision; - dst->num_subauth = min_t(u8, src->num_subauth, SID_MAX_SUB_AUTHORITIES); - for (i = 0; i < NUM_AUTHS; ++i) - dst->authority[i] = src->authority[i]; - for (i = 0; i < dst->num_subauth; ++i) - dst->sub_auth[i] = src->sub_auth[i]; -} - -static int -id_to_sid(unsigned int cid, uint sidtype, struct cifs_sid *ssid) -{ - int rc; - struct key *sidkey; - struct cifs_sid *ksid; - unsigned int ksid_size; - char desc[3 + 10 + 1]; /* 3 byte prefix + 10 bytes for value + NULL */ - const struct cred *saved_cred; - - rc = snprintf(desc, sizeof(desc), "%ci:%u", - sidtype == SIDOWNER ? 'o' : 'g', cid); - if (rc >= sizeof(desc)) - return -EINVAL; - - rc = 0; - saved_cred = override_creds(root_cred); - sidkey = request_key(&cifs_idmap_key_type, desc, ""); - if (IS_ERR(sidkey)) { - rc = -EINVAL; - cifs_dbg(FYI, "%s: Can't map %cid %u to a SID\n", - __func__, sidtype == SIDOWNER ? 'u' : 'g', cid); - goto out_revert_creds; - } else if (sidkey->datalen < CIFS_SID_BASE_SIZE) { - rc = -EIO; - cifs_dbg(FYI, "%s: Downcall contained malformed key (datalen=%hu)\n", - __func__, sidkey->datalen); - goto invalidate_key; - } - - /* - * A sid is usually too large to be embedded in payload.value, but if - * there are no subauthorities and the host has 8-byte pointers, then - * it could be. - */ - ksid = sidkey->datalen <= sizeof(sidkey->payload) ? - (struct cifs_sid *)&sidkey->payload.value : - (struct cifs_sid *)sidkey->payload.data; - - ksid_size = CIFS_SID_BASE_SIZE + (ksid->num_subauth * sizeof(__le32)); - if (ksid_size > sidkey->datalen) { - rc = -EIO; - cifs_dbg(FYI, "%s: Downcall contained malformed key (datalen=%hu, ksid_size=%u)\n", - __func__, sidkey->datalen, ksid_size); - goto invalidate_key; - } - - cifs_copy_sid(ssid, ksid); -out_key_put: - key_put(sidkey); -out_revert_creds: - revert_creds(saved_cred); - return rc; - -invalidate_key: - key_invalidate(sidkey); - goto out_key_put; -} - -static int -sid_to_id(struct cifs_sb_info *cifs_sb, struct cifs_sid *psid, - struct cifs_fattr *fattr, uint sidtype) -{ - int rc; - struct key *sidkey; - char *sidstr; - const struct cred *saved_cred; - kuid_t fuid = cifs_sb->mnt_uid; - kgid_t fgid = cifs_sb->mnt_gid; - - /* - * If we have too many subauthorities, then something is really wrong. - * Just return an error. - */ - if (unlikely(psid->num_subauth > SID_MAX_SUB_AUTHORITIES)) { - cifs_dbg(FYI, "%s: %u subauthorities is too many!\n", - __func__, psid->num_subauth); - return -EIO; - } - - sidstr = sid_to_key_str(psid, sidtype); - if (!sidstr) - return -ENOMEM; - - saved_cred = override_creds(root_cred); - sidkey = request_key(&cifs_idmap_key_type, sidstr, ""); - if (IS_ERR(sidkey)) { - rc = -EINVAL; - cifs_dbg(FYI, "%s: Can't map SID %s to a %cid\n", - __func__, sidstr, sidtype == SIDOWNER ? 'u' : 'g'); - goto out_revert_creds; - } - - /* - * FIXME: Here we assume that uid_t and gid_t are same size. It's - * probably a safe assumption but might be better to check based on - * sidtype. - */ - BUILD_BUG_ON(sizeof(uid_t) != sizeof(gid_t)); - if (sidkey->datalen != sizeof(uid_t)) { - rc = -EIO; - cifs_dbg(FYI, "%s: Downcall contained malformed key (datalen=%hu)\n", - __func__, sidkey->datalen); - key_invalidate(sidkey); - goto out_key_put; - } - - if (sidtype == SIDOWNER) { - kuid_t uid; - uid_t id; - memcpy(&id, &sidkey->payload.value, sizeof(uid_t)); - uid = make_kuid(&init_user_ns, id); - if (uid_valid(uid)) - fuid = uid; - } else { - kgid_t gid; - gid_t id; - memcpy(&id, &sidkey->payload.value, sizeof(gid_t)); - gid = make_kgid(&init_user_ns, id); - if (gid_valid(gid)) - fgid = gid; - } - -out_key_put: - key_put(sidkey); -out_revert_creds: - revert_creds(saved_cred); - kfree(sidstr); - - /* - * Note that we return 0 here unconditionally. If the mapping - * fails then we just fall back to using the mnt_uid/mnt_gid. - */ - if (sidtype == SIDOWNER) - fattr->cf_uid = fuid; - else - fattr->cf_gid = fgid; - return 0; -} - -int -init_cifs_idmap(void) -{ - struct cred *cred; - struct key *keyring; - int ret; - - cifs_dbg(FYI, "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 = keyring_alloc(".cifs_idmap", - 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); - if (IS_ERR(keyring)) { - ret = PTR_ERR(keyring); - goto failed_put_cred; - } - - 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 */ - set_bit(KEY_FLAG_ROOT_CAN_CLEAR, &keyring->flags); - cred->thread_keyring = keyring; - cred->jit_keyring = KEY_REQKEY_DEFL_THREAD_KEYRING; - root_cred = cred; - - cifs_dbg(FYI, "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); - cifs_dbg(FYI, "Unregistered %s key type\n", cifs_idmap_key_type.name); -} - -/* 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) -{ - 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); - cifs_copy_sid(nowner_sid_ptr, owner_sid_ptr); - - /* 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)); - cifs_copy_sid(ngroup_sid_ptr, group_sid_ptr); - - 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) { - cifs_dbg(VFS, "unknown access control type %d\n", type); - return; - } - /* else ACCESS_ALLOWED type */ - - if (flags & GENERIC_ALL) { - *pmode |= (S_IRWXUGO & (*pbits_to_set)); - cifs_dbg(NOISY, "all perms\n"); - 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)); - - cifs_dbg(NOISY, "access flags 0x%x mode now 0x%x\n", 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; - - cifs_dbg(NOISY, "mode: 0x%x, access flags now 0x%x\n", - 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 < NUM_AUTHS; 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) { - cifs_dbg(VFS, "ACE too small %d\n", le16_to_cpu(pace->size)); - return; - } - - if (end_of_acl < (char *)pace + le16_to_cpu(pace->size)) { - cifs_dbg(VFS, "ACL too small to parse ACE\n"); - return; - } - - num_subauth = pace->sid.num_subauth; - if (num_subauth) { - int i; - cifs_dbg(FYI, "ACE revision %d num_auth %d type %d flags %d size %d\n", - pace->sid.revision, pace->sid.num_subauth, pace->type, - pace->flags, le16_to_cpu(pace->size)); - for (i = 0; i < num_subauth; ++i) { - cifs_dbg(FYI, "ACE sub_auth[%d]: 0x%x\n", - 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)) { - cifs_dbg(VFS, "ACL too small to parse DACL\n"); - return; - } - - cifs_dbg(NOISY, "DACL revision %d size %d num aces %d\n", - 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; - - if (num_aces > ULONG_MAX / sizeof(struct cifs_ace *)) - return; - ppace = kmalloc(num_aces * sizeof(struct cifs_ace *), - GFP_KERNEL); - if (!ppace) - 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) { - cifs_dbg(VFS, "ACL too small to parse SID %p\n", psid); - return -EINVAL; - } - -#ifdef CONFIG_CIFS_DEBUG2 - if (psid->num_subauth) { - int i; - cifs_dbg(FYI, "SID revision %d num_auth %d\n", - psid->revision, psid->num_subauth); - - for (i = 0; i < psid->num_subauth; i++) { - cifs_dbg(FYI, "SID sub_auth[%d]: 0x%x\n", - 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 */ - cifs_dbg(FYI, "RID 0x%x\n", - 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); - cifs_dbg(NOISY, "revision %d type 0x%x ooffset 0x%x goffset 0x%x sacloffset 0x%x dacloffset 0x%x\n", - 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) { - cifs_dbg(FYI, "%s: Error %d parsing Owner SID\n", __func__, rc); - return rc; - } - rc = sid_to_id(cifs_sb, owner_sid_ptr, fattr, SIDOWNER); - if (rc) { - cifs_dbg(FYI, "%s: Error %d mapping Owner SID to uid\n", - __func__, rc); - return rc; - } - - rc = parse_sid(group_sid_ptr, end_of_acl); - if (rc) { - cifs_dbg(FYI, "%s: Error %d mapping Owner SID to gid\n", - __func__, rc); - return rc; - } - rc = sid_to_id(cifs_sb, group_sid_ptr, fattr, SIDGROUP); - if (rc) { - cifs_dbg(FYI, "%s: Error %d mapping Group SID to gid\n", - __func__, rc); - return rc; - } - - if (dacloffset) - parse_dacl(dacl_ptr, end_of_acl, owner_sid_ptr, - group_sid_ptr, fattr); - else - cifs_dbg(FYI, "no ACL\n"); /* BB grant all or default perms? */ - - return rc; -} - -/* Convert permission bits from mode to equivalent CIFS ACL */ -static int build_sec_desc(struct cifs_ntsd *pntsd, struct cifs_ntsd *pnntsd, - __u32 secdesclen, __u64 nmode, kuid_t uid, kgid_t gid, int *aclflag) -{ - int rc = 0; - __u32 dacloffset; - __u32 ndacloffset; - __u32 sidsoffset; - struct cifs_sid *owner_sid_ptr, *group_sid_ptr; - struct cifs_sid *nowner_sid_ptr, *ngroup_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 (nmode != NO_CHANGE_64) { /* chmod */ - 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 sec desc control portion & owner and group sids */ - copy_sec_desc(pntsd, pnntsd, sidsoffset); - *aclflag = CIFS_ACL_DACL; - } else { - memcpy(pnntsd, pntsd, secdesclen); - if (uid_valid(uid)) { /* chown */ - uid_t id; - owner_sid_ptr = (struct cifs_sid *)((char *)pnntsd + - le32_to_cpu(pnntsd->osidoffset)); - nowner_sid_ptr = kmalloc(sizeof(struct cifs_sid), - GFP_KERNEL); - if (!nowner_sid_ptr) - return -ENOMEM; - id = from_kuid(&init_user_ns, uid); - rc = id_to_sid(id, SIDOWNER, nowner_sid_ptr); - if (rc) { - cifs_dbg(FYI, "%s: Mapping error %d for owner id %d\n", - __func__, rc, id); - kfree(nowner_sid_ptr); - return rc; - } - cifs_copy_sid(owner_sid_ptr, nowner_sid_ptr); - kfree(nowner_sid_ptr); - *aclflag = CIFS_ACL_OWNER; - } - if (gid_valid(gid)) { /* chgrp */ - gid_t id; - group_sid_ptr = (struct cifs_sid *)((char *)pnntsd + - le32_to_cpu(pnntsd->gsidoffset)); - ngroup_sid_ptr = kmalloc(sizeof(struct cifs_sid), - GFP_KERNEL); - if (!ngroup_sid_ptr) - return -ENOMEM; - id = from_kgid(&init_user_ns, gid); - rc = id_to_sid(id, SIDGROUP, ngroup_sid_ptr); - if (rc) { - cifs_dbg(FYI, "%s: Mapping error %d for group id %d\n", - __func__, rc, id); - kfree(ngroup_sid_ptr); - return rc; - } - cifs_copy_sid(group_sid_ptr, ngroup_sid_ptr); - kfree(ngroup_sid_ptr); - *aclflag = CIFS_ACL_GROUP; - } - } - - 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; - unsigned int xid; - int rc; - struct tcon_link *tlink = cifs_sb_tlink(cifs_sb); - - if (IS_ERR(tlink)) - return ERR_CAST(tlink); - - xid = get_xid(); - rc = CIFSSMBGetCIFSACL(xid, tlink_tcon(tlink), fid, &pntsd, pacllen); - free_xid(xid); - - cifs_put_tlink(tlink); - - cifs_dbg(FYI, "%s: rc = %d ACL len %d\n", __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; - unsigned int xid; - int rc, create_options = 0; - __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 = get_xid(); - - if (backup_cred(cifs_sb)) - create_options |= CREATE_OPEN_BACKUP_INTENT; - - rc = CIFSSMBOpen(xid, tcon, path, FILE_OPEN, READ_CONTROL, - create_options, &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); - free_xid(xid); - - cifs_dbg(FYI, "%s: rc = %d ACL len %d\n", __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->fid.netfid, pacllen); - cifsFileInfo_put(open_file); - return pntsd; -} - - /* Set an ACL on the server */ -int set_cifs_acl(struct cifs_ntsd *pnntsd, __u32 acllen, - struct inode *inode, const char *path, int aclflag) -{ - int oplock = 0; - unsigned int xid; - int rc, access_flags, create_options = 0; - __u16 fid; - struct cifs_tcon *tcon; - struct cifs_sb_info *cifs_sb = CIFS_SB(inode->i_sb); - struct tcon_link *tlink = cifs_sb_tlink(cifs_sb); - - if (IS_ERR(tlink)) - return PTR_ERR(tlink); - - tcon = tlink_tcon(tlink); - xid = get_xid(); - - if (backup_cred(cifs_sb)) - create_options |= CREATE_OPEN_BACKUP_INTENT; - - if (aclflag == CIFS_ACL_OWNER || aclflag == CIFS_ACL_GROUP) - access_flags = WRITE_OWNER; - else - access_flags = WRITE_DAC; - - rc = CIFSSMBOpen(xid, tcon, path, FILE_OPEN, access_flags, - create_options, &fid, &oplock, NULL, cifs_sb->local_nls, - cifs_sb->mnt_cifs_flags & CIFS_MOUNT_MAP_SPECIAL_CHR); - if (rc) { - cifs_dbg(VFS, "Unable to open file to set ACL\n"); - goto out; - } - - rc = CIFSSMBSetCIFSACL(xid, tcon, fid, pnntsd, acllen, aclflag); - cifs_dbg(NOISY, "SetCIFSACL rc = %d\n", rc); - - CIFSSMBClose(xid, tcon, fid); -out: - free_xid(xid); - cifs_put_tlink(tlink); - 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; - - cifs_dbg(NOISY, "converting ACL to mode for %s\n", 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); - cifs_dbg(VFS, "%s: error %d getting sec desc\n", __func__, rc); - } else { - rc = parse_sec_desc(cifs_sb, pntsd, acllen, fattr); - kfree(pntsd); - if (rc) - cifs_dbg(VFS, "parse sec desc failed rc = %d\n", rc); - } - - return rc; -} - -/* Convert mode bits to an ACL so we can update the ACL on the server */ -int -id_mode_to_cifs_acl(struct inode *inode, const char *path, __u64 nmode, - kuid_t uid, kgid_t gid) -{ - int rc = 0; - int aclflag = CIFS_ACL_DACL; /* default flag to set */ - __u32 secdesclen = 0; - struct cifs_ntsd *pntsd = NULL; /* acl obtained from server */ - struct cifs_ntsd *pnntsd = NULL; /* modified acl to be sent to server */ - - cifs_dbg(NOISY, "set ACL from mode for %s\n", path); - - /* Get the security descriptor */ - pntsd = get_cifs_acl(CIFS_SB(inode->i_sb), inode, path, &secdesclen); - if (IS_ERR(pntsd)) { - rc = PTR_ERR(pntsd); - cifs_dbg(VFS, "%s: error %d getting sec desc\n", __func__, rc); - goto out; - } - - /* - * Add three ACEs for owner, group, everyone getting rid of other ACEs - * as chmod disables ACEs and set the security descriptor. Allocate - * memory for the smb header, set security descriptor request security - * descriptor parameters, and secuirty descriptor itself - */ - secdesclen = max_t(u32, secdesclen, DEFAULT_SEC_DESC_LEN); - pnntsd = kmalloc(secdesclen, GFP_KERNEL); - if (!pnntsd) { - kfree(pntsd); - return -ENOMEM; - } - - rc = build_sec_desc(pntsd, pnntsd, secdesclen, nmode, uid, gid, - &aclflag); - - cifs_dbg(NOISY, "build_sec_desc rc: %d\n", rc); - - if (!rc) { - /* Set the security descriptor */ - rc = set_cifs_acl(pnntsd, secdesclen, inode, path, aclflag); - cifs_dbg(NOISY, "set_cifs_acl rc: %d\n", rc); - } - - kfree(pnntsd); - kfree(pntsd); -out: - return rc; -} |