/* * fs/nfs4acl/acl.c * * Common NFSv4 ACL handling code. * * Copyright (c) 2002, 2003 The Regents of the University of Michigan. * All rights reserved. * * Marius Aamodt Eriksen * Jeff Sedlak * J. Bruce Fields * * 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 #include /* mode bit translations: */ #define NFS4_READ_MODE (NFS4_ACE_READ_DATA) #define NFS4_WRITE_MODE (NFS4_ACE_WRITE_DATA | NFS4_ACE_APPEND_DATA) #define NFS4_EXECUTE_MODE NFS4_ACE_EXECUTE #define NFS4_ANYONE_MODE (NFS4_ACE_READ_ATTRIBUTES | NFS4_ACE_READ_ACL | NFS4_ACE_SYNCHRONIZE) #define NFS4_OWNER_MODE (NFS4_ACE_WRITE_ATTRIBUTES | NFS4_ACE_WRITE_ACL) /* We don't support these bits; insist they be neither allowed nor denied */ #define NFS4_MASK_UNSUPP (NFS4_ACE_DELETE | NFS4_ACE_WRITE_OWNER \ | NFS4_ACE_READ_NAMED_ATTRS | NFS4_ACE_WRITE_NAMED_ATTRS) /* flags used to simulate posix default ACLs */ #define NFS4_INHERITANCE_FLAGS (NFS4_ACE_FILE_INHERIT_ACE \ | NFS4_ACE_DIRECTORY_INHERIT_ACE) #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) ) static u32 mask_from_posix(unsigned short perm, unsigned int flags) { int mask = NFS4_ANYONE_MODE; if (flags & NFS4_ACL_OWNER) mask |= NFS4_OWNER_MODE; 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; } static u32 deny_mask_from_posix(unsigned short perm, u32 flags) { 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 * used by nfs code, after all.... */ /* We only map from NFSv4 to POSIX ACLs when setting ACLs, when we err on the * side of being more restrictive, so the mode bit mapping below is * pessimistic. An optimistic version would be needed to handle DENY's, * but we espect to coalesce all ALLOWs and DENYs before mapping to mode * bits. */ static void low_mode_from_nfs4(u32 perm, unsigned short *mode, unsigned int flags) { u32 write_mode = NFS4_WRITE_MODE; if (flags & NFS4_ACL_DIR) write_mode |= NFS4_ACE_DELETE_CHILD; *mode = 0; if ((perm & NFS4_READ_MODE) == NFS4_READ_MODE) *mode |= ACL_READ; if ((perm & write_mode) == write_mode) *mode |= ACL_WRITE; if ((perm & NFS4_EXECUTE_MODE) == NFS4_EXECUTE_MODE) *mode |= ACL_EXECUTE; } struct ace_container { struct nfs4_ace *ace; struct list_head ace_l; }; static short ace2type(struct nfs4_ace *); static void _posix_to_nfsv4_one(struct posix_acl *, struct nfs4_acl *, unsigned int); struct nfs4_acl * nfs4_acl_posix_to_nfsv4(struct posix_acl *pacl, struct posix_acl *dpacl, unsigned int flags) { struct nfs4_acl *acl; int size = 0; if (pacl) { if (posix_acl_valid(pacl) < 0) return ERR_PTR(-EINVAL); size += 2*pacl->a_count; } if (dpacl) { if (posix_acl_valid(dpacl) < 0) return ERR_PTR(-EINVAL); size += 2*dpacl->a_count; } /* Allocate for worst case: one (deny, allow) pair each: */ acl = nfs4_acl_new(size); if (acl == NULL) return ERR_PTR(-ENOMEM); if (pacl) _posix_to_nfsv4_one(pacl, acl, flags & ~NFS4_ACL_TYPE_DEFAULT); if (dpacl) _posix_to_nfsv4_one(dpacl, acl, flags | NFS4_ACL_TYPE_DEFAULT); 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 summarize_posix_acl(struct posix_acl *acl, struct posix_acl_summary *pas) { struct posix_acl_entry *pa, *pe; /* * Only pas.users and pas.groups need initialization; previous * posix_acl_valid() calls ensure that the other fields will be * initialized in the following loop. But, just to placate gcc: */ memset(pas, 0, sizeof(*pas)); 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 void _posix_to_nfsv4_one(struct posix_acl *pacl, struct nfs4_acl *acl, unsigned int flags) { 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 | NFS4_ACE_INHERIT_ONLY_ACE : 0); BUG_ON(pacl->a_count < 3); summarize_posix_acl(pacl, &pas); pa = pacl->a_entries; 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) { 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++; } /* In the case of groups, we apply allow ACEs first, then deny ACEs, * since a user can be in more than one group. */ /* allow ACEs */ group_owner_entry = pa; 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) { 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; deny = ~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_GROUP; ace++; acl->naces++; } pa++; while (pa->e_tag == ACL_GROUP) { 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 = deny_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++; 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 sort_pacl_range(struct posix_acl *pacl, int start, int end) { int sorted = 0, i; struct posix_acl_entry tmp; /* We just do a bubble sort; easy to do in place, and we're not * expecting acl's to be long enough to justify anything more. */ while (!sorted) { sorted = 1; for (i = start; i < end; i++) { if (pacl->a_entries[i].e_id > pacl->a_entries[i+1].e_id) { sorted = 0; tmp = pacl->a_entries[i]; pacl->a_entries[i] = pacl->a_entries[i+1]; pacl->a_entries[i+1] = tmp; } } } } static void sort_pacl(struct posix_acl *pacl) { /* posix_acl_valid requires that users and groups be in order * by uid/gid. */ int i, j; if (pacl->a_count <= 4) return; /* no users or groups */ i = 1; while (pacl->a_entries[i].e_tag == ACL_USER) i++; sort_pacl_range(pacl, 1, i-1); BUG_ON(pacl->a_entries[i].e_tag != ACL_GROUP_OBJ); j = ++i; while (pacl->a_entries[j].e_tag == ACL_GROUP) j++; sort_pacl_range(pacl, i, j-1); return; } /* * While processing the NFSv4 ACE, this maintains bitmasks representing * which permission bits have been allowed and which denied to a given * entity: */ struct posix_ace_state { u32 allow; u32 deny; }; struct posix_user_ace_state { uid_t uid; struct posix_ace_state perms; }; struct posix_ace_state_array { int n; struct posix_user_ace_state aces[]; }; /* * While processing the NFSv4 ACE, this maintains the partial permissions * calculated so far: */ struct posix_acl_state { int empty; struct posix_ace_state owner; struct posix_ace_state group; struct posix_ace_state other; struct posix_ace_state everyone; struct posix_ace_state mask; /* Deny unused in this case */ struct posix_ace_state_array *users; struct posix_ace_state_array *groups; }; static int 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 * enough space for either: */ alloc = sizeof(struct posix_ace_state_array) + cnt*sizeof(struct posix_user_ace_state); state->users = kzalloc(alloc, GFP_KERNEL); if (!state->users) return -ENOMEM; state->groups = kzalloc(alloc, GFP_KERNEL); if (!state->groups) { kfree(state->users); return -ENOMEM; } return 0; } static void free_state(struct posix_acl_state *state) { kfree(state->users); kfree(state->groups); } static inline void add_to_mask(struct posix_acl_state *state, struct posix_ace_state *astate) { state->mask.allow |= astate->allow; } /* * Certain bits (SYNCHRONIZE, DELETE, WRITE_OWNER, READ/WRITE_NAMED_ATTRS, * READ_ATTRIBUTES, READ_ACL) are currently unenforceable and don't translate * to traditional read/write/execute permissions. * * It's problematic to reject acls that use certain mode bits, because it * places the burden on users to learn the rules about which bits one * particular server sets, without giving the user a lot of help--we return an * error that could mean any number of different things. To make matters * worse, the problematic bits might be introduced by some application that's * automatically mapping from some other acl model. * * So wherever possible we accept anything, possibly erring on the side of * denying more permissions than necessary. * * However we do reject *explicit* DENY's of a few bits representing * permissions we could never deny: */ static inline int check_deny(u32 mask, int isowner) { if (mask & (NFS4_ACE_READ_ATTRIBUTES | NFS4_ACE_READ_ACL)) return -EINVAL; if (!isowner) return 0; if (mask & (NFS4_ACE_WRITE_ATTRIBUTES | NFS4_ACE_WRITE_ACL)) return -EINVAL; return 0; } static struct posix_acl * posix_state_to_acl(struct posix_acl_state *state, unsigned int flags) { struct posix_acl_entry *pace; struct posix_acl *pacl; 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) return ERR_PTR(-ENOMEM); pace = pacl->a_entries; pace->e_tag = ACL_USER_OBJ; error = check_deny(state->owner.deny, 1); if (error) goto out_err; low_mode_from_nfs4(state->owner.allow, &pace->e_perm, flags); pace->e_id = ACL_UNDEFINED_ID; for (i=0; i < state->users->n; i++) { pace++; pace->e_tag = ACL_USER; error = check_deny(state->users->aces[i].perms.deny, 0); if (error) goto out_err; low_mode_from_nfs4(state->users->aces[i].perms.allow, &pace->e_perm, flags); pace->e_id = state->users->aces[i].uid; add_to_mask(state, &state->users->aces[i].perms); } pace++; pace->e_tag = ACL_GROUP_OBJ; error = check_deny(state->group.deny, 0); if (error) goto out_err; low_mode_from_nfs4(state->group.allow, &pace->e_perm, flags); pace->e_id = ACL_UNDEFINED_ID; add_to_mask(state, &state->group); for (i=0; i < state->groups->n; i++) { pace++; pace->e_tag = ACL_GROUP; error = check_deny(state->groups->aces[i].perms.deny, 0); if (error) goto out_err; low_mode_from_nfs4(state->groups->aces[i].perms.allow, &pace->e_perm, flags); pace->e_id = state->groups->aces[i].uid; add_to_mask(state, &state->groups->aces[i].perms); } pace++; pace->e_tag = ACL_MASK; low_mode_from_nfs4(state->mask.allow, &pace->e_perm, flags); pace->e_id = ACL_UNDEFINED_ID; pace++; pace->e_tag = ACL_OTHER; error = check_deny(state->other.deny, 0); if (error) goto out_err; low_mode_from_nfs4(state->other.allow, &pace->e_perm, flags); pace->e_id = ACL_UNDEFINED_ID; return pacl; out_err: posix_acl_release(pacl); return ERR_PTR(error); } static inline void allow_bits(struct posix_ace_state *astate, u32 mask) { /* Allow all bits in the mask not already denied: */ astate->allow |= mask & ~astate->deny; } static inline void deny_bits(struct posix_ace_state *astate, u32 mask) { /* Deny all bits in the mask not already allowed: */ astate->deny |= mask & ~astate->allow; } static int find_uid(struct posix_acl_state *state, struct posix_ace_state_array *a, uid_t uid) { int i; for (i = 0; i < a->n; i++) if (a->aces[i].uid == uid) return i; /* Not found: */ a->n++; a->aces[i].uid = uid; a->aces[i].perms.allow = state->everyone.allow; a->aces[i].perms.deny = state->everyone.deny; return i; } static void deny_bits_array(struct posix_ace_state_array *a, u32 mask) { int i; for (i=0; i < a->n; i++) deny_bits(&a->aces[i].perms, mask); } static void allow_bits_array(struct posix_ace_state_array *a, u32 mask) { int i; for (i=0; i < a->n; i++) allow_bits(&a->aces[i].perms, mask); } static void process_one_v4_ace(struct posix_acl_state *state, struct nfs4_ace *ace) { 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) { allow_bits(&state->owner, mask); } else { deny_bits(&state->owner, mask); } break; case ACL_USER: i = find_uid(state, state->users, ace->who); if (ace->type == NFS4_ACE_ACCESS_ALLOWED_ACE_TYPE) { allow_bits(&state->users->aces[i].perms, mask); } else { deny_bits(&state->users->aces[i].perms, mask); mask = state->users->aces[i].perms.deny; deny_bits(&state->owner, mask); } break; case ACL_GROUP_OBJ: if (ace->type == NFS4_ACE_ACCESS_ALLOWED_ACE_TYPE) { allow_bits(&state->group, mask); } else { deny_bits(&state->group, mask); mask = state->group.deny; deny_bits(&state->owner, mask); deny_bits(&state->everyone, mask); deny_bits_array(state->users, mask); deny_bits_array(state->groups, mask); } break; case ACL_GROUP: i = find_uid(state, state->groups, ace->who); if (ace->type == NFS4_ACE_ACCESS_ALLOWED_ACE_TYPE) { allow_bits(&state->groups->aces[i].perms, mask); } else { deny_bits(&state->groups->aces[i].perms, mask); mask = state->groups->aces[i].perms.deny; deny_bits(&state->owner, mask); deny_bits(&state->group, mask); deny_bits(&state->everyone, mask); deny_bits_array(state->users, mask); deny_bits_array(state->groups, mask); } break; case ACL_OTHER: if (ace->type == NFS4_ACE_ACCESS_ALLOWED_ACE_TYPE) { allow_bits(&state->owner, mask); allow_bits(&state->group, mask); allow_bits(&state->other, mask); allow_bits(&state->everyone, mask); allow_bits_array(state->users, mask); allow_bits_array(state->groups, mask); } else { deny_bits(&state->owner, mask); deny_bits(&state->group, mask); deny_bits(&state->other, mask); deny_bits(&state->everyone, mask); deny_bits_array(state->users, mask); deny_bits_array(state->groups, mask); } } } 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 effective_acl_state, default_acl_state; struct nfs4_ace *ace; int ret; ret = init_state(&effective_acl_state, acl->naces); if (ret) 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) goto out_dstate; if (ace->flag & ~NFS4_SUPPORTED_FLAGS) goto out_dstate; if ((ace->flag & NFS4_INHERITANCE_FLAGS) == 0) { process_one_v4_ace(&effective_acl_state, ace); continue; } 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); } *pacl = posix_state_to_acl(&effective_acl_state, flags); if (IS_ERR(*pacl)) { ret = PTR_ERR(*pacl); *pacl = NULL; goto out_dstate; } *dpacl = posix_state_to_acl(&default_acl_state, flags | NFS4_ACL_TYPE_DEFAULT); if (IS_ERR(*dpacl)) { ret = PTR_ERR(*dpacl); *dpacl = NULL; posix_acl_release(*pacl); *pacl = NULL; 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 ace2type(struct nfs4_ace *ace) { switch (ace->whotype) { case NFS4_ACL_WHO_NAMED: return (ace->flag & NFS4_ACE_IDENTIFIER_GROUP ? ACL_GROUP : ACL_USER); case NFS4_ACL_WHO_OWNER: return ACL_USER_OBJ; case NFS4_ACL_WHO_GROUP: return ACL_GROUP_OBJ; case NFS4_ACL_WHO_EVERYONE: return ACL_OTHER; } BUG(); return -1; } EXPORT_SYMBOL(nfs4_acl_posix_to_nfsv4); EXPORT_SYMBOL(nfs4_acl_nfsv4_to_posix); struct nfs4_acl * nfs4_acl_new(int n) { struct nfs4_acl *acl; acl = kmalloc(sizeof(*acl) + n*sizeof(struct nfs4_ace), GFP_KERNEL); if (acl == NULL) return NULL; acl->naces = 0; return acl; } static struct { char *string; int stringlen; int type; } s2t_map[] = { { .string = "OWNER@", .stringlen = sizeof("OWNER@") - 1, .type = NFS4_ACL_WHO_OWNER, }, { .string = "GROUP@", .stringlen = sizeof("GROUP@") - 1, .type = NFS4_ACL_WHO_GROUP, }, { .string = "EVERYONE@", .stringlen = sizeof("EVERYONE@") - 1, .type = NFS4_ACL_WHO_EVERYONE, }, }; int nfs4_acl_get_whotype(char *p, u32 len) { int i; for (i = 0; i < ARRAY_SIZE(s2t_map); i++) { if (s2t_map[i].stringlen == len && 0 == memcmp(s2t_map[i].string, p, len)) return s2t_map[i].type; } return NFS4_ACL_WHO_NAMED; } int nfs4_acl_write_who(int who, char *p) { int i; for (i = 0; i < ARRAY_SIZE(s2t_map); i++) { if (s2t_map[i].type == who) { memcpy(p, s2t_map[i].string, s2t_map[i].stringlen); return s2t_map[i].stringlen; } } BUG(); return -1; } EXPORT_SYMBOL(nfs4_acl_new); EXPORT_SYMBOL(nfs4_acl_get_whotype); EXPORT_SYMBOL(nfs4_acl_write_who);