diff options
Diffstat (limited to 'fs/nfsd/nfs4acl.c')
-rw-r--r-- | fs/nfsd/nfs4acl.c | 491 |
1 files changed, 238 insertions, 253 deletions
diff --git a/fs/nfsd/nfs4acl.c b/fs/nfsd/nfs4acl.c index 5d94555cdc8..832673b1458 100644 --- a/fs/nfsd/nfs4acl.c +++ b/fs/nfsd/nfs4acl.c @@ -61,9 +61,11 @@ /* flags used to simulate posix default ACLs */ #define NFS4_INHERITANCE_FLAGS (NFS4_ACE_FILE_INHERIT_ACE \ - | NFS4_ACE_DIRECTORY_INHERIT_ACE | NFS4_ACE_INHERIT_ONLY_ACE) + | NFS4_ACE_DIRECTORY_INHERIT_ACE) -#define NFS4_SUPPORTED_FLAGS (NFS4_INHERITANCE_FLAGS | NFS4_ACE_IDENTIFIER_GROUP) +#define NFS4_SUPPORTED_FLAGS (NFS4_INHERITANCE_FLAGS \ + | NFS4_ACE_INHERIT_ONLY_ACE \ + | NFS4_ACE_IDENTIFIER_GROUP) #define MASK_EQUAL(mask1, mask2) \ ( ((mask1) & NFS4_ACE_MASK_ALL) == ((mask2) & NFS4_ACE_MASK_ALL) ) @@ -87,12 +89,19 @@ mask_from_posix(unsigned short perm, unsigned int flags) } static u32 -deny_mask(u32 allow_mask, unsigned int flags) +deny_mask_from_posix(unsigned short perm, u32 flags) { - u32 ret = ~allow_mask & ~NFS4_MASK_UNSUPP; - if (!(flags & NFS4_ACL_DIR)) - ret &= ~NFS4_ACE_DELETE_CHILD; - return ret; + u32 mask = 0; + + if (perm & ACL_READ) + mask |= NFS4_READ_MODE; + if (perm & ACL_WRITE) + mask |= NFS4_WRITE_MODE; + if ((perm & ACL_WRITE) && (flags & NFS4_ACL_DIR)) + mask |= NFS4_ACE_DELETE_CHILD; + if (perm & ACL_EXECUTE) + mask |= NFS4_EXECUTE_MODE; + return mask; } /* XXX: modify functions to return NFS errors; they're only ever @@ -126,108 +135,151 @@ struct ace_container { }; static short ace2type(struct nfs4_ace *); -static int _posix_to_nfsv4_one(struct posix_acl *, struct nfs4_acl *, unsigned int); -static struct posix_acl *_nfsv4_to_posix_one(struct nfs4_acl *, unsigned int); -int nfs4_acl_add_ace(struct nfs4_acl *, u32, u32, u32, int, uid_t); -static int nfs4_acl_split(struct nfs4_acl *, struct nfs4_acl *); +static void _posix_to_nfsv4_one(struct posix_acl *, struct nfs4_acl *, + unsigned int); +void nfs4_acl_add_ace(struct nfs4_acl *, u32, u32, u32, int, uid_t); struct nfs4_acl * nfs4_acl_posix_to_nfsv4(struct posix_acl *pacl, struct posix_acl *dpacl, unsigned int flags) { struct nfs4_acl *acl; - int error = -EINVAL; + int size = 0; - if ((pacl != NULL && - (posix_acl_valid(pacl) < 0 || pacl->a_count == 0)) || - (dpacl != NULL && - (posix_acl_valid(dpacl) < 0 || dpacl->a_count == 0))) - goto out_err; - - acl = nfs4_acl_new(); - if (acl == NULL) { - error = -ENOMEM; - goto out_err; + if (pacl) { + if (posix_acl_valid(pacl) < 0) + return ERR_PTR(-EINVAL); + size += 2*pacl->a_count; } - - if (pacl != NULL) { - error = _posix_to_nfsv4_one(pacl, acl, - flags & ~NFS4_ACL_TYPE_DEFAULT); - if (error < 0) - goto out_acl; + if (dpacl) { + if (posix_acl_valid(dpacl) < 0) + return ERR_PTR(-EINVAL); + size += 2*dpacl->a_count; } - if (dpacl != NULL) { - error = _posix_to_nfsv4_one(dpacl, acl, - flags | NFS4_ACL_TYPE_DEFAULT); - if (error < 0) - goto out_acl; - } + /* Allocate for worst case: one (deny, allow) pair each: */ + acl = nfs4_acl_new(size); + if (acl == NULL) + return ERR_PTR(-ENOMEM); - return acl; + if (pacl) + _posix_to_nfsv4_one(pacl, acl, flags & ~NFS4_ACL_TYPE_DEFAULT); -out_acl: - nfs4_acl_free(acl); -out_err: - acl = ERR_PTR(error); + if (dpacl) + _posix_to_nfsv4_one(dpacl, acl, flags | NFS4_ACL_TYPE_DEFAULT); return acl; } -static int -nfs4_acl_add_pair(struct nfs4_acl *acl, int eflag, u32 mask, int whotype, - uid_t owner, unsigned int flags) +struct posix_acl_summary { + unsigned short owner; + unsigned short users; + unsigned short group; + unsigned short groups; + unsigned short other; + unsigned short mask; +}; + +static void +summarize_posix_acl(struct posix_acl *acl, struct posix_acl_summary *pas) { - int error; - - error = nfs4_acl_add_ace(acl, NFS4_ACE_ACCESS_ALLOWED_ACE_TYPE, - eflag, mask, whotype, owner); - if (error < 0) - return error; - error = nfs4_acl_add_ace(acl, NFS4_ACE_ACCESS_DENIED_ACE_TYPE, - eflag, deny_mask(mask, flags), whotype, owner); - return error; + struct posix_acl_entry *pa, *pe; + pas->users = 0; + pas->groups = 0; + pas->mask = 07; + + pe = acl->a_entries + acl->a_count; + + FOREACH_ACL_ENTRY(pa, acl, pe) { + switch (pa->e_tag) { + case ACL_USER_OBJ: + pas->owner = pa->e_perm; + break; + case ACL_GROUP_OBJ: + pas->group = pa->e_perm; + break; + case ACL_USER: + pas->users |= pa->e_perm; + break; + case ACL_GROUP: + pas->groups |= pa->e_perm; + break; + case ACL_OTHER: + pas->other = pa->e_perm; + break; + case ACL_MASK: + pas->mask = pa->e_perm; + break; + } + } + /* We'll only care about effective permissions: */ + pas->users &= pas->mask; + pas->group &= pas->mask; + pas->groups &= pas->mask; } /* We assume the acl has been verified with posix_acl_valid. */ -static int +static void _posix_to_nfsv4_one(struct posix_acl *pacl, struct nfs4_acl *acl, unsigned int flags) { - struct posix_acl_entry *pa, *pe, *group_owner_entry; - int error = -EINVAL; - u32 mask, mask_mask; + struct posix_acl_entry *pa, *group_owner_entry; + struct nfs4_ace *ace; + struct posix_acl_summary pas; + unsigned short deny; int eflag = ((flags & NFS4_ACL_TYPE_DEFAULT) ? NFS4_INHERITANCE_FLAGS : 0); BUG_ON(pacl->a_count < 3); - pe = pacl->a_entries + pacl->a_count; - pa = pe - 2; /* if mask entry exists, it's second from the last. */ - if (pa->e_tag == ACL_MASK) - mask_mask = deny_mask(mask_from_posix(pa->e_perm, flags), flags); - else - mask_mask = 0; + summarize_posix_acl(pacl, &pas); pa = pacl->a_entries; - BUG_ON(pa->e_tag != ACL_USER_OBJ); - mask = mask_from_posix(pa->e_perm, flags | NFS4_ACL_OWNER); - error = nfs4_acl_add_pair(acl, eflag, mask, NFS4_ACL_WHO_OWNER, 0, flags); - if (error < 0) - goto out; - pa++; + ace = acl->aces + acl->naces; - while (pa->e_tag == ACL_USER) { - mask = mask_from_posix(pa->e_perm, flags); - error = nfs4_acl_add_ace(acl, NFS4_ACE_ACCESS_DENIED_ACE_TYPE, - eflag, mask_mask, NFS4_ACL_WHO_NAMED, pa->e_id); - if (error < 0) - goto out; + /* We could deny everything not granted by the owner: */ + deny = ~pas.owner; + /* + * but it is equivalent (and simpler) to deny only what is not + * granted by later entries: + */ + deny &= pas.users | pas.group | pas.groups | pas.other; + if (deny) { + ace->type = NFS4_ACE_ACCESS_DENIED_ACE_TYPE; + ace->flag = eflag; + ace->access_mask = deny_mask_from_posix(deny, flags); + ace->whotype = NFS4_ACL_WHO_OWNER; + ace++; + acl->naces++; + } + ace->type = NFS4_ACE_ACCESS_ALLOWED_ACE_TYPE; + ace->flag = eflag; + ace->access_mask = mask_from_posix(pa->e_perm, flags | NFS4_ACL_OWNER); + ace->whotype = NFS4_ACL_WHO_OWNER; + ace++; + acl->naces++; + pa++; - error = nfs4_acl_add_pair(acl, eflag, mask, - NFS4_ACL_WHO_NAMED, pa->e_id, flags); - if (error < 0) - goto out; + while (pa->e_tag == ACL_USER) { + deny = ~(pa->e_perm & pas.mask); + deny &= pas.groups | pas.group | pas.other; + if (deny) { + ace->type = NFS4_ACE_ACCESS_DENIED_ACE_TYPE; + ace->flag = eflag; + ace->access_mask = deny_mask_from_posix(deny, flags); + ace->whotype = NFS4_ACL_WHO_NAMED; + ace->who = pa->e_id; + ace++; + acl->naces++; + } + ace->type = NFS4_ACE_ACCESS_ALLOWED_ACE_TYPE; + ace->flag = eflag; + ace->access_mask = mask_from_posix(pa->e_perm & pas.mask, + flags); + ace->whotype = NFS4_ACL_WHO_NAMED; + ace->who = pa->e_id; + ace++; + acl->naces++; pa++; } @@ -236,67 +288,65 @@ _posix_to_nfsv4_one(struct posix_acl *pacl, struct nfs4_acl *acl, /* allow ACEs */ - if (pacl->a_count > 3) { - BUG_ON(pa->e_tag != ACL_GROUP_OBJ); - error = nfs4_acl_add_ace(acl, NFS4_ACE_ACCESS_DENIED_ACE_TYPE, - NFS4_ACE_IDENTIFIER_GROUP | eflag, mask_mask, - NFS4_ACL_WHO_GROUP, 0); - if (error < 0) - goto out; - } group_owner_entry = pa; - mask = mask_from_posix(pa->e_perm, flags); - error = nfs4_acl_add_ace(acl, NFS4_ACE_ACCESS_ALLOWED_ACE_TYPE, - NFS4_ACE_IDENTIFIER_GROUP | eflag, mask, - NFS4_ACL_WHO_GROUP, 0); - if (error < 0) - goto out; + + ace->type = NFS4_ACE_ACCESS_ALLOWED_ACE_TYPE; + ace->flag = eflag; + ace->access_mask = mask_from_posix(pas.group, flags); + ace->whotype = NFS4_ACL_WHO_GROUP; + ace++; + acl->naces++; pa++; while (pa->e_tag == ACL_GROUP) { - mask = mask_from_posix(pa->e_perm, flags); - error = nfs4_acl_add_ace(acl, NFS4_ACE_ACCESS_DENIED_ACE_TYPE, - NFS4_ACE_IDENTIFIER_GROUP | eflag, mask_mask, - NFS4_ACL_WHO_NAMED, pa->e_id); - if (error < 0) - goto out; - - error = nfs4_acl_add_ace(acl, NFS4_ACE_ACCESS_ALLOWED_ACE_TYPE, - NFS4_ACE_IDENTIFIER_GROUP | eflag, mask, - NFS4_ACL_WHO_NAMED, pa->e_id); - if (error < 0) - goto out; + ace->type = NFS4_ACE_ACCESS_ALLOWED_ACE_TYPE; + ace->flag = eflag | NFS4_ACE_IDENTIFIER_GROUP; + ace->access_mask = mask_from_posix(pa->e_perm & pas.mask, + flags); + ace->whotype = NFS4_ACL_WHO_NAMED; + ace->who = pa->e_id; + ace++; + acl->naces++; pa++; } /* deny ACEs */ pa = group_owner_entry; - mask = mask_from_posix(pa->e_perm, flags); - error = nfs4_acl_add_ace(acl, NFS4_ACE_ACCESS_DENIED_ACE_TYPE, - NFS4_ACE_IDENTIFIER_GROUP | eflag, - deny_mask(mask, flags), NFS4_ACL_WHO_GROUP, 0); - if (error < 0) - goto out; + + deny = ~pas.group & pas.other; + if (deny) { + ace->type = NFS4_ACE_ACCESS_DENIED_ACE_TYPE; + ace->flag = eflag | NFS4_ACE_IDENTIFIER_GROUP; + ace->access_mask = deny_mask_from_posix(deny, flags); + ace->whotype = NFS4_ACL_WHO_GROUP; + ace++; + acl->naces++; + } pa++; + while (pa->e_tag == ACL_GROUP) { - mask = mask_from_posix(pa->e_perm, flags); - error = nfs4_acl_add_ace(acl, NFS4_ACE_ACCESS_DENIED_ACE_TYPE, - NFS4_ACE_IDENTIFIER_GROUP | eflag, - deny_mask(mask, flags), NFS4_ACL_WHO_NAMED, pa->e_id); - if (error < 0) - goto out; + deny = ~(pa->e_perm & pas.mask); + deny &= pas.other; + if (deny) { + ace->type = NFS4_ACE_ACCESS_DENIED_ACE_TYPE; + ace->flag = eflag | NFS4_ACE_IDENTIFIER_GROUP; + ace->access_mask = mask_from_posix(deny, flags); + ace->whotype = NFS4_ACL_WHO_NAMED; + ace->who = pa->e_id; + ace++; + acl->naces++; + } pa++; } if (pa->e_tag == ACL_MASK) pa++; - BUG_ON(pa->e_tag != ACL_OTHER); - mask = mask_from_posix(pa->e_perm, flags); - error = nfs4_acl_add_pair(acl, eflag, mask, NFS4_ACL_WHO_EVERYONE, 0, flags); - -out: - return error; + ace->type = NFS4_ACE_ACCESS_ALLOWED_ACE_TYPE; + ace->flag = eflag; + ace->access_mask = mask_from_posix(pa->e_perm, flags); + ace->whotype = NFS4_ACL_WHO_EVERYONE; + acl->naces++; } static void @@ -342,46 +392,6 @@ sort_pacl(struct posix_acl *pacl) return; } -int -nfs4_acl_nfsv4_to_posix(struct nfs4_acl *acl, struct posix_acl **pacl, - struct posix_acl **dpacl, unsigned int flags) -{ - struct nfs4_acl *dacl; - int error = -ENOMEM; - - *pacl = NULL; - *dpacl = NULL; - - dacl = nfs4_acl_new(); - if (dacl == NULL) - goto out; - - error = nfs4_acl_split(acl, dacl); - if (error) - goto out_acl; - - *pacl = _nfsv4_to_posix_one(acl, flags); - if (IS_ERR(*pacl)) { - error = PTR_ERR(*pacl); - *pacl = NULL; - goto out_acl; - } - - *dpacl = _nfsv4_to_posix_one(dacl, flags); - if (IS_ERR(*dpacl)) { - error = PTR_ERR(*dpacl); - *dpacl = NULL; - } -out_acl: - if (error) { - posix_acl_release(*pacl); - *pacl = NULL; - } - nfs4_acl_free(dacl); -out: - return error; -} - /* * While processing the NFSv4 ACE, this maintains bitmasks representing * which permission bits have been allowed and which denied to a given @@ -406,6 +416,7 @@ struct posix_ace_state_array { * calculated so far: */ struct posix_acl_state { + int empty; struct posix_ace_state owner; struct posix_ace_state group; struct posix_ace_state other; @@ -421,6 +432,7 @@ init_state(struct posix_acl_state *state, int cnt) int alloc; memset(state, 0, sizeof(struct posix_acl_state)); + state->empty = 1; /* * In the worst case, each individual acl could be for a distinct * named user or group, but we don't no which, so we allocate @@ -488,6 +500,20 @@ posix_state_to_acl(struct posix_acl_state *state, unsigned int flags) int nace; int i, error = 0; + /* + * ACLs with no ACEs are treated differently in the inheritable + * and effective cases: when there are no inheritable ACEs, we + * set a zero-length default posix acl: + */ + if (state->empty && (flags & NFS4_ACL_TYPE_DEFAULT)) { + pacl = posix_acl_alloc(0, GFP_KERNEL); + return pacl ? pacl : ERR_PTR(-ENOMEM); + } + /* + * When there are no effective ACEs, the following will end + * up setting a 3-element effective posix ACL with all + * permissions zero. + */ nace = 4 + state->users->n + state->groups->n; pacl = posix_acl_alloc(nace, GFP_KERNEL); if (!pacl) @@ -603,6 +629,8 @@ static void process_one_v4_ace(struct posix_acl_state *state, u32 mask = ace->access_mask; int i; + state->empty = 0; + switch (ace2type(ace)) { case ACL_USER_OBJ: if (ace->type == NFS4_ACE_ACCESS_ALLOWED_ACE_TYPE) { @@ -666,75 +694,62 @@ static void process_one_v4_ace(struct posix_acl_state *state, } } -static struct posix_acl * -_nfsv4_to_posix_one(struct nfs4_acl *n4acl, unsigned int flags) +int nfs4_acl_nfsv4_to_posix(struct nfs4_acl *acl, struct posix_acl **pacl, + struct posix_acl **dpacl, unsigned int flags) { - struct posix_acl_state state; - struct posix_acl *pacl; + struct posix_acl_state effective_acl_state, default_acl_state; struct nfs4_ace *ace; int ret; - ret = init_state(&state, n4acl->naces); + ret = init_state(&effective_acl_state, acl->naces); if (ret) - return ERR_PTR(ret); - - list_for_each_entry(ace, &n4acl->ace_head, l_ace) - process_one_v4_ace(&state, ace); - - pacl = posix_state_to_acl(&state, flags); - - free_state(&state); - - if (!IS_ERR(pacl)) - sort_pacl(pacl); - return pacl; -} - -static int -nfs4_acl_split(struct nfs4_acl *acl, struct nfs4_acl *dacl) -{ - struct list_head *h, *n; - struct nfs4_ace *ace; - int error = 0; - - list_for_each_safe(h, n, &acl->ace_head) { - ace = list_entry(h, struct nfs4_ace, l_ace); - + return ret; + ret = init_state(&default_acl_state, acl->naces); + if (ret) + goto out_estate; + ret = -EINVAL; + for (ace = acl->aces; ace < acl->aces + acl->naces; ace++) { if (ace->type != NFS4_ACE_ACCESS_ALLOWED_ACE_TYPE && ace->type != NFS4_ACE_ACCESS_DENIED_ACE_TYPE) - return -EINVAL; - + goto out_dstate; if (ace->flag & ~NFS4_SUPPORTED_FLAGS) - return -EINVAL; - - switch (ace->flag & NFS4_INHERITANCE_FLAGS) { - case 0: - /* Leave this ace in the effective acl: */ + goto out_dstate; + if ((ace->flag & NFS4_INHERITANCE_FLAGS) == 0) { + process_one_v4_ace(&effective_acl_state, ace); continue; - case NFS4_INHERITANCE_FLAGS: - /* Add this ace to the default acl and remove it - * from the effective acl: */ - error = nfs4_acl_add_ace(dacl, ace->type, ace->flag, - ace->access_mask, ace->whotype, ace->who); - if (error) - return error; - list_del(h); - kfree(ace); - acl->naces--; - break; - case NFS4_INHERITANCE_FLAGS & ~NFS4_ACE_INHERIT_ONLY_ACE: - /* Add this ace to the default, but leave it in - * the effective acl as well: */ - error = nfs4_acl_add_ace(dacl, ace->type, ace->flag, - ace->access_mask, ace->whotype, ace->who); - if (error) - return error; - break; - default: - return -EINVAL; } + if (!(flags & NFS4_ACL_DIR)) + goto out_dstate; + /* + * Note that when only one of FILE_INHERIT or DIRECTORY_INHERIT + * is set, we're effectively turning on the other. That's OK, + * according to rfc 3530. + */ + process_one_v4_ace(&default_acl_state, ace); + + if (!(ace->flag & NFS4_ACE_INHERIT_ONLY_ACE)) + process_one_v4_ace(&effective_acl_state, ace); } - return 0; + *pacl = posix_state_to_acl(&effective_acl_state, flags); + if (IS_ERR(*pacl)) { + ret = PTR_ERR(*pacl); + goto out_dstate; + } + *dpacl = posix_state_to_acl(&default_acl_state, + flags | NFS4_ACL_TYPE_DEFAULT); + if (IS_ERR(*dpacl)) { + ret = PTR_ERR(*dpacl); + posix_acl_release(*pacl); + goto out_dstate; + } + sort_pacl(*pacl); + sort_pacl(*dpacl); + ret = 0; +out_dstate: + free_state(&default_acl_state); +out_estate: + free_state(&effective_acl_state); + return ret; } static short @@ -759,48 +774,22 @@ EXPORT_SYMBOL(nfs4_acl_posix_to_nfsv4); EXPORT_SYMBOL(nfs4_acl_nfsv4_to_posix); struct nfs4_acl * -nfs4_acl_new(void) +nfs4_acl_new(int n) { struct nfs4_acl *acl; - if ((acl = kmalloc(sizeof(*acl), GFP_KERNEL)) == NULL) + acl = kmalloc(sizeof(*acl) + n*sizeof(struct nfs4_ace), GFP_KERNEL); + if (acl == NULL) return NULL; - acl->naces = 0; - INIT_LIST_HEAD(&acl->ace_head); - return acl; } void -nfs4_acl_free(struct nfs4_acl *acl) -{ - struct list_head *h; - struct nfs4_ace *ace; - - if (!acl) - return; - - while (!list_empty(&acl->ace_head)) { - h = acl->ace_head.next; - list_del(h); - ace = list_entry(h, struct nfs4_ace, l_ace); - kfree(ace); - } - - kfree(acl); - - return; -} - -int nfs4_acl_add_ace(struct nfs4_acl *acl, u32 type, u32 flag, u32 access_mask, int whotype, uid_t who) { - struct nfs4_ace *ace; - - if ((ace = kmalloc(sizeof(*ace), GFP_KERNEL)) == NULL) - return -ENOMEM; + struct nfs4_ace *ace = acl->aces + acl->naces; ace->type = type; ace->flag = flag; @@ -808,10 +797,7 @@ nfs4_acl_add_ace(struct nfs4_acl *acl, u32 type, u32 flag, u32 access_mask, ace->whotype = whotype; ace->who = who; - list_add_tail(&ace->l_ace, &acl->ace_head); acl->naces++; - - return 0; } static struct { @@ -865,7 +851,6 @@ nfs4_acl_write_who(int who, char *p) } EXPORT_SYMBOL(nfs4_acl_new); -EXPORT_SYMBOL(nfs4_acl_free); EXPORT_SYMBOL(nfs4_acl_add_ace); EXPORT_SYMBOL(nfs4_acl_get_whotype); EXPORT_SYMBOL(nfs4_acl_write_who); |