diff --git a/fs/nfsd/nfs4acl.c b/fs/nfsd/nfs4acl.c index 8daa3f8bb303..0a69cce33efe 100644 --- a/fs/nfsd/nfs4acl.c +++ b/fs/nfsd/nfs4acl.c @@ -89,12 +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 @@ -164,14 +171,51 @@ nfs4_acl_posix_to_nfsv4(struct posix_acl *pacl, struct posix_acl *dpacl, return acl; } +struct posix_acl_summary { + unsigned short owner; + unsigned short users; + unsigned short group; + unsigned short groups; + unsigned short other; + unsigned short mask; +}; + static void -nfs4_acl_add_pair(struct nfs4_acl *acl, int eflag, u32 mask, int whotype, - uid_t owner, unsigned int flags) +summarize_posix_acl(struct posix_acl *acl, struct posix_acl_summary *pas) { - nfs4_acl_add_ace(acl, NFS4_ACE_ACCESS_ALLOWED_ACE_TYPE, - eflag, mask, whotype, owner); - nfs4_acl_add_ace(acl, NFS4_ACE_ACCESS_DENIED_ACE_TYPE, - eflag, deny_mask(mask, flags), whotype, owner); + 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. */ @@ -179,30 +223,63 @@ 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; - u32 mask; - unsigned short 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 = pa->e_perm; - else - mask_mask = S_IRWXO; + 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); - nfs4_acl_add_pair(acl, eflag, mask, NFS4_ACL_WHO_OWNER, 0, flags); + ace = acl->aces + acl->naces; + + /* 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++; while (pa->e_tag == ACL_USER) { - mask = mask_from_posix(pa->e_perm & mask_mask, flags); - nfs4_acl_add_pair(acl, eflag, mask, - NFS4_ACL_WHO_NAMED, pa->e_id, flags); + 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++; } @@ -212,41 +289,64 @@ _posix_to_nfsv4_one(struct posix_acl *pacl, struct nfs4_acl *acl, /* allow ACEs */ group_owner_entry = pa; - mask = mask_from_posix(pa->e_perm & mask_mask, flags); - nfs4_acl_add_ace(acl, NFS4_ACE_ACCESS_ALLOWED_ACE_TYPE, - NFS4_ACE_IDENTIFIER_GROUP | eflag, mask, - NFS4_ACL_WHO_GROUP, 0); + + 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 & mask_mask, flags); - nfs4_acl_add_ace(acl, NFS4_ACE_ACCESS_ALLOWED_ACE_TYPE, - NFS4_ACE_IDENTIFIER_GROUP | eflag, mask, - NFS4_ACL_WHO_NAMED, pa->e_id); + 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); - 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); + + 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); - 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); + 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); - nfs4_acl_add_pair(acl, eflag, mask, NFS4_ACL_WHO_EVERYONE, 0, flags); + 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