| /* Test whether a file has a nontrivial ACL. -*- coding: utf-8 -*- | |
| Copyright (C) 2002-2003, 2005-2026 Free Software Foundation, Inc. | |
| This program is free software: you can redistribute it and/or modify | |
| it under the terms of the GNU General Public License as published by | |
| the Free Software Foundation, either version 3 of the License, or | |
| (at your option) any later version. | |
| This program 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 General Public License for more details. | |
| You should have received a copy of the GNU General Public License | |
| along with this program. If not, see <https://www.gnu.org/licenses/>. | |
| Written by Paul Eggert, Andreas Grünbacher, and Bruno Haible. */ | |
| #define ACL_INTERNAL_INLINE _GL_EXTERN_INLINE | |
| #include <config.h> | |
| /* Specification. */ | |
| #include "acl-internal.h" | |
| #include "acl.h" | |
| #if defined __CYGWIN__ | |
| # include <sys/types.h> | |
| # include <grp.h> | |
| # include <string.h> | |
| #endif | |
| #if USE_ACL && HAVE_ACL_GET_FILE /* Linux, FreeBSD, NetBSD >= 10, Mac OS X, Cygwin >= 2.5 */ | |
| # if HAVE_ACL_TYPE_EXTENDED /* Mac OS X */ | |
| /* ACL is an ACL, from a file, stored as type ACL_TYPE_EXTENDED. | |
| Return 1 if the given ACL is non-trivial. | |
| Return 0 if it is trivial. */ | |
| int | |
| acl_extended_nontrivial (acl_t acl) | |
| { | |
| /* acl is non-trivial if it is non-empty. */ | |
| return (acl_entries (acl) > 0); | |
| } | |
| # else /* Linux, FreeBSD, NetBSD >= 10, Cygwin >= 2.5 */ | |
| /* ACL is an ACL, from a file, stored as type ACL_TYPE_ACCESS. | |
| Return 1 if the given ACL is non-trivial. | |
| Return 0 if it is trivial, i.e. equivalent to a simple stat() mode. | |
| Return -1 and set errno upon failure to determine it. */ | |
| int | |
| acl_access_nontrivial (acl_t acl) | |
| { | |
| /* acl is non-trivial if it has some entries other than for "user::", | |
| "group::", and "other::". Normally these three should be present | |
| at least, allowing us to write | |
| return (3 < acl_entries (acl)); | |
| but the following code is more robust. */ | |
| # if HAVE_ACL_FIRST_ENTRY /* Linux, FreeBSD, NetBSD >= 10, Cygwin >= 2.5 */ | |
| acl_entry_t ace; | |
| int got_one; | |
| for (got_one = acl_get_entry (acl, ACL_FIRST_ENTRY, &ace); | |
| got_one > 0; | |
| got_one = acl_get_entry (acl, ACL_NEXT_ENTRY, &ace)) | |
| { | |
| acl_tag_t tag; | |
| if (acl_get_tag_type (ace, &tag) < 0) | |
| return -1; | |
| switch (tag) | |
| { | |
| case ACL_USER_OBJ: | |
| case ACL_GROUP_OBJ: | |
| case ACL_OTHER: | |
| break; | |
| # ifdef __CYGWIN__ | |
| /* On Cygwin, a trivial ACL inside the Cygwin file system consists of | |
| e.g. | |
| user::rwx | |
| group::r-x | |
| other::r-x | |
| but a trivial ACL outside the Cygwin file system has more entries: | |
| e.g. | |
| user::rwx | |
| group::r-x | |
| group:SYSTEM:rwx | |
| group:Administrators:rwx | |
| mask::r-x | |
| other::r-x | |
| or | |
| user::rwx | |
| group::r-x | |
| group:SYSTEM:rwx | |
| group:Administrators:rwx | |
| group:Users:rwx | |
| mask::rwx | |
| other::r-x | |
| */ | |
| case ACL_GROUP: | |
| { | |
| int ignorable = 0; | |
| void *qualifier = acl_get_qualifier (ace); | |
| if (qualifier != NULL) | |
| { | |
| gid_t group_id = *(gid_t const *) qualifier; | |
| acl_free (qualifier); | |
| struct group *group_details = getgrgid (group_id); | |
| if (group_details != NULL) | |
| { | |
| const char *group_sid = group_details->gr_passwd; | |
| /* Ignore the ace if the group_sid is one of | |
| - S-1-5-18 (group "SYSTEM") | |
| - S-1-5-32-544 (group "Administrators") | |
| - S-1-5-32-545 (group "Users") | |
| Cf. <https://learn.microsoft.com/en-us/windows/win32/secauthz/well-known-sids> | |
| and look at the output of the 'mkgroup' command. */ | |
| ignorable = (streq (group_sid, "S-1-5-18") | |
| || streq (group_sid, "S-1-5-32-544") | |
| || streq (group_sid, "S-1-5-32-545")); | |
| } | |
| } | |
| if (!ignorable) | |
| return 1; | |
| } | |
| break; | |
| case ACL_MASK: | |
| /* XXX Is it OK to ignore acl_get_permset (ace, ...) ? */ | |
| break; | |
| # endif | |
| default: | |
| return 1; | |
| } | |
| } | |
| return got_one; | |
| # else | |
| errno = ENOSYS; | |
| return -1; | |
| # endif | |
| } | |
| int | |
| acl_default_nontrivial (acl_t acl) | |
| { | |
| /* acl is non-trivial if it is non-empty. */ | |
| return (acl_entries (acl) > 0); | |
| } | |
| # endif | |
| #elif USE_ACL && HAVE_FACL && defined GETACL /* Solaris, Cygwin < 2.5, not HP-UX */ | |
| /* Test an ACL retrieved with GETACL. | |
| Return 1 if the given ACL, consisting of COUNT entries, is non-trivial. | |
| Return 0 if it is trivial, i.e. equivalent to a simple stat() mode. */ | |
| int | |
| acl_nontrivial (int count, aclent_t *entries) | |
| { | |
| for (int i = 0; i < count; i++) | |
| { | |
| aclent_t *ace = &entries[i]; | |
| /* Note: If ace->a_type = USER_OBJ, ace->a_id is the st_uid from stat(). | |
| If ace->a_type = GROUP_OBJ, ace->a_id is the st_gid from stat(). | |
| We don't need to check ace->a_id in these cases. */ | |
| if (!(ace->a_type == USER_OBJ | |
| || ace->a_type == GROUP_OBJ | |
| || ace->a_type == OTHER_OBJ | |
| /* Note: Cygwin does not return a CLASS_OBJ ("mask:") entry | |
| sometimes. */ | |
| || ace->a_type == CLASS_OBJ)) | |
| return 1; | |
| } | |
| return 0; | |
| } | |
| # ifdef ACE_GETACL | |
| /* A shortcut for a bitmask. */ | |
| # define NEW_ACE_WRITEA_DATA (NEW_ACE_WRITE_DATA | NEW_ACE_APPEND_DATA) | |
| /* Test an ACL retrieved with ACE_GETACL. | |
| Return 1 if the given ACL, consisting of COUNT entries, is non-trivial. | |
| Return 0 if it is trivial, i.e. equivalent to a simple stat() mode. */ | |
| int | |
| acl_ace_nontrivial (int count, ace_t *entries) | |
| { | |
| /* The flags in the ace_t structure changed in a binary incompatible way | |
| when ACL_NO_TRIVIAL etc. were introduced in <sys/acl.h> version 1.15. | |
| How to distinguish the two conventions at runtime? | |
| In the old convention, usually three ACEs have a_flags = ACE_OWNER / | |
| ACE_GROUP / ACE_OTHER, in the range 0x0100..0x0400. In the new | |
| convention, these values are not used. */ | |
| int old_convention = 0; | |
| for (int i = 0; i < count; i++) | |
| if (entries[i].a_flags & (OLD_ACE_OWNER | OLD_ACE_GROUP | OLD_ACE_OTHER)) | |
| { | |
| old_convention = 1; | |
| break; | |
| } | |
| if (old_convention) | |
| /* Running on Solaris 10. */ | |
| for (int i = 0; i < count; i++) | |
| { | |
| ace_t *ace = &entries[i]; | |
| /* Note: | |
| If ace->a_flags = ACE_OWNER, ace->a_who is the st_uid from stat(). | |
| If ace->a_flags = ACE_GROUP, ace->a_who is the st_gid from stat(). | |
| We don't need to check ace->a_who in these cases. */ | |
| if (!(ace->a_type == OLD_ALLOW | |
| && (ace->a_flags == OLD_ACE_OWNER | |
| || ace->a_flags == OLD_ACE_GROUP | |
| || ace->a_flags == OLD_ACE_OTHER))) | |
| return 1; | |
| } | |
| else | |
| { | |
| /* Running on Solaris 10 (newer version) or Solaris 11. */ | |
| unsigned int access_masks[6] = | |
| { | |
| 0, /* owner@ deny */ | |
| 0, /* owner@ allow */ | |
| 0, /* group@ deny */ | |
| 0, /* group@ allow */ | |
| 0, /* everyone@ deny */ | |
| 0 /* everyone@ allow */ | |
| }; | |
| for (int i = 0; i < count; i++) | |
| { | |
| ace_t *ace = &entries[i]; | |
| unsigned int index1; | |
| if (ace->a_type == NEW_ACE_ACCESS_ALLOWED_ACE_TYPE) | |
| index1 = 1; | |
| else if (ace->a_type == NEW_ACE_ACCESS_DENIED_ACE_TYPE) | |
| index1 = 0; | |
| else | |
| return 1; | |
| unsigned int index2; | |
| if (ace->a_flags == NEW_ACE_OWNER) | |
| index2 = 0; | |
| else if (ace->a_flags == (NEW_ACE_GROUP | NEW_ACE_IDENTIFIER_GROUP)) | |
| index2 = 2; | |
| else if (ace->a_flags == NEW_ACE_EVERYONE) | |
| index2 = 4; | |
| else | |
| return 1; | |
| access_masks[index1 + index2] |= ace->a_access_mask; | |
| } | |
| /* The same bit shouldn't be both allowed and denied. */ | |
| if (access_masks[0] & access_masks[1]) | |
| return 1; | |
| if (access_masks[2] & access_masks[3]) | |
| return 1; | |
| if (access_masks[4] & access_masks[5]) | |
| return 1; | |
| /* Check minimum masks. */ | |
| if ((NEW_ACE_WRITE_NAMED_ATTRS | |
| | NEW_ACE_WRITE_ATTRIBUTES | |
| | NEW_ACE_WRITE_ACL | |
| | NEW_ACE_WRITE_OWNER) | |
| & ~ access_masks[1]) | |
| return 1; | |
| access_masks[1] &= ~(NEW_ACE_WRITE_NAMED_ATTRS | |
| | NEW_ACE_WRITE_ATTRIBUTES | |
| | NEW_ACE_WRITE_ACL | |
| | NEW_ACE_WRITE_OWNER); | |
| if ((NEW_ACE_READ_NAMED_ATTRS | |
| | NEW_ACE_READ_ATTRIBUTES | |
| | NEW_ACE_READ_ACL | |
| | NEW_ACE_SYNCHRONIZE) | |
| & ~ access_masks[5]) | |
| return 1; | |
| access_masks[5] &= ~(NEW_ACE_READ_NAMED_ATTRS | |
| | NEW_ACE_READ_ATTRIBUTES | |
| | NEW_ACE_READ_ACL | |
| | NEW_ACE_SYNCHRONIZE); | |
| /* Check the allowed or denied bits. */ | |
| switch ((access_masks[0] | access_masks[1]) | |
| & ~(NEW_ACE_READ_NAMED_ATTRS | |
| | NEW_ACE_READ_ATTRIBUTES | |
| | NEW_ACE_READ_ACL | |
| | NEW_ACE_SYNCHRONIZE)) | |
| { | |
| case 0: | |
| case NEW_ACE_READ_DATA: | |
| case NEW_ACE_WRITEA_DATA: | |
| case NEW_ACE_READ_DATA | NEW_ACE_WRITEA_DATA: | |
| case NEW_ACE_EXECUTE: | |
| case NEW_ACE_READ_DATA | NEW_ACE_EXECUTE: | |
| case NEW_ACE_WRITEA_DATA | NEW_ACE_EXECUTE: | |
| case NEW_ACE_READ_DATA | NEW_ACE_WRITEA_DATA | NEW_ACE_EXECUTE: | |
| break; | |
| default: | |
| return 1; | |
| } | |
| switch ((access_masks[2] | access_masks[3]) | |
| & ~(NEW_ACE_READ_NAMED_ATTRS | |
| | NEW_ACE_READ_ATTRIBUTES | |
| | NEW_ACE_READ_ACL | |
| | NEW_ACE_SYNCHRONIZE)) | |
| { | |
| case 0: | |
| case NEW_ACE_READ_DATA: | |
| case NEW_ACE_WRITEA_DATA: | |
| case NEW_ACE_READ_DATA | NEW_ACE_WRITEA_DATA: | |
| case NEW_ACE_EXECUTE: | |
| case NEW_ACE_READ_DATA | NEW_ACE_EXECUTE: | |
| case NEW_ACE_WRITEA_DATA | NEW_ACE_EXECUTE: | |
| case NEW_ACE_READ_DATA | NEW_ACE_WRITEA_DATA | NEW_ACE_EXECUTE: | |
| break; | |
| default: | |
| return 1; | |
| } | |
| switch ((access_masks[4] | access_masks[5]) | |
| & ~(NEW_ACE_WRITE_NAMED_ATTRS | |
| | NEW_ACE_WRITE_ATTRIBUTES | |
| | NEW_ACE_WRITE_ACL | |
| | NEW_ACE_WRITE_OWNER)) | |
| { | |
| case 0: | |
| case NEW_ACE_READ_DATA: | |
| case NEW_ACE_WRITEA_DATA: | |
| case NEW_ACE_READ_DATA | NEW_ACE_WRITEA_DATA: | |
| case NEW_ACE_EXECUTE: | |
| case NEW_ACE_READ_DATA | NEW_ACE_EXECUTE: | |
| case NEW_ACE_WRITEA_DATA | NEW_ACE_EXECUTE: | |
| case NEW_ACE_READ_DATA | NEW_ACE_WRITEA_DATA | NEW_ACE_EXECUTE: | |
| break; | |
| default: | |
| return 1; | |
| } | |
| /* Check that the NEW_ACE_WRITE_DATA and NEW_ACE_APPEND_DATA bits are | |
| either both allowed or both denied. */ | |
| if (((access_masks[0] & NEW_ACE_WRITE_DATA) != 0) | |
| != ((access_masks[0] & NEW_ACE_APPEND_DATA) != 0)) | |
| return 1; | |
| if (((access_masks[2] & NEW_ACE_WRITE_DATA) != 0) | |
| != ((access_masks[2] & NEW_ACE_APPEND_DATA) != 0)) | |
| return 1; | |
| if (((access_masks[4] & NEW_ACE_WRITE_DATA) != 0) | |
| != ((access_masks[4] & NEW_ACE_APPEND_DATA) != 0)) | |
| return 1; | |
| } | |
| return 0; | |
| } | |
| # endif | |
| #elif USE_ACL && HAVE_GETACL /* HP-UX */ | |
| /* Return 1 if the given ACL is non-trivial. | |
| Return 0 if it is trivial, i.e. equivalent to a simple stat() mode. */ | |
| int | |
| acl_nontrivial (int count, struct acl_entry *entries) | |
| { | |
| if (count > 3) | |
| return 1; | |
| for (int i = 0; i < count; i++) | |
| { | |
| struct acl_entry *ace = &entries[i]; | |
| if (ace->uid != ACL_NSUSER && ace->gid != ACL_NSGROUP) | |
| return 1; | |
| } | |
| return 0; | |
| } | |
| # if HAVE_ACLV_H /* HP-UX >= 11.11 */ | |
| /* Return 1 if the given ACL is non-trivial. | |
| Return 0 if it is trivial, i.e. equivalent to a simple stat() mode. */ | |
| int | |
| aclv_nontrivial (int count, struct acl *entries) | |
| { | |
| for (int i = 0; i < count; i++) | |
| { | |
| struct acl *ace = &entries[i]; | |
| /* Note: If ace->a_type = USER_OBJ, ace->a_id is the st_uid from stat(). | |
| If ace->a_type = GROUP_OBJ, ace->a_id is the st_gid from stat(). | |
| We don't need to check ace->a_id in these cases. */ | |
| if (!(ace->a_type == USER_OBJ /* no need to check ace->a_id here */ | |
| || ace->a_type == GROUP_OBJ /* no need to check ace->a_id here */ | |
| || ace->a_type == CLASS_OBJ | |
| || ace->a_type == OTHER_OBJ)) | |
| return 1; | |
| } | |
| return 0; | |
| } | |
| # endif | |
| #elif USE_ACL && (HAVE_ACLX_GET || HAVE_STATACL) /* AIX */ | |
| /* Return 1 if the given ACL is non-trivial. | |
| Return 0 if it is trivial, i.e. equivalent to a simple stat() mode. */ | |
| int | |
| acl_nontrivial (struct acl *a) | |
| { | |
| /* The normal way to iterate through an ACL is like this: | |
| for (struct acl_entry *ace = a->acl_ext; ace != acl_last (a); ace = acl_nxt (ace)) | |
| { | |
| switch (ace->ace_type) | |
| { | |
| case ACC_PERMIT: | |
| case ACC_DENY: | |
| case ACC_SPECIFY: | |
| ...; | |
| } | |
| for (struct ace_id *aei = ace->ace_id; aei != id_last (ace); aei = id_nxt (aei)) | |
| ... | |
| } | |
| */ | |
| return (acl_last (a) != a->acl_ext ? 1 : 0); | |
| } | |
| # if HAVE_ACLX_GET && defined ACL_AIX_WIP /* newer AIX */ | |
| /* Return 1 if the given ACL is non-trivial. | |
| Return 0 if it is trivial, i.e. equivalent to a simple stat() mode. */ | |
| int | |
| acl_nfs4_nontrivial (nfs4_acl_int_t *a) | |
| { | |
| # if 1 /* let's try this first */ | |
| return (a->aclEntryN > 0 ? 1 : 0); | |
| # else | |
| int count = a->aclEntryN; | |
| for (int i = 0; i < count; i++) | |
| { | |
| nfs4_ace_int_t *ace = &a->aclEntry[i]; | |
| if (!((ace->flags & ACE4_ID_SPECIAL) != 0 | |
| && (ace->aceWho.special_whoid == ACE4_WHO_OWNER | |
| || ace->aceWho.special_whoid == ACE4_WHO_GROUP | |
| || ace->aceWho.special_whoid == ACE4_WHO_EVERYONE) | |
| && ace->aceType == ACE4_ACCESS_ALLOWED_ACE_TYPE | |
| && ace->aceFlags == 0 | |
| && (ace->aceMask & ~(ACE4_READ_DATA | ACE4_LIST_DIRECTORY | |
| | ACE4_WRITE_DATA | ACE4_ADD_FILE | |
| | ACE4_EXECUTE)) == 0)) | |
| return 1; | |
| } | |
| return 0; | |
| # endif | |
| } | |
| # endif | |
| #elif USE_ACL && HAVE_ACLSORT /* NonStop Kernel */ | |
| /* Test an ACL retrieved with ACL_GET. | |
| Return 1 if the given ACL, consisting of COUNT entries, is non-trivial. | |
| Return 0 if it is trivial, i.e. equivalent to a simple stat() mode. */ | |
| int | |
| acl_nontrivial (int count, struct acl *entries) | |
| { | |
| for (int i = 0; i < count; i++) | |
| { | |
| struct acl *ace = &entries[i]; | |
| /* Note: If ace->a_type = USER_OBJ, ace->a_id is the st_uid from stat(). | |
| If ace->a_type = GROUP_OBJ, ace->a_id is the st_gid from stat(). | |
| We don't need to check ace->a_id in these cases. */ | |
| if (!(ace->a_type == USER_OBJ /* no need to check ace->a_id here */ | |
| || ace->a_type == GROUP_OBJ /* no need to check ace->a_id here */ | |
| || ace->a_type == CLASS_OBJ | |
| || ace->a_type == OTHER_OBJ)) | |
| return 1; | |
| } | |
| return 0; | |
| } | |
| #endif | |
| void | |
| free_permission_context (struct permission_context *ctx) | |
| { | |
| #if USE_ACL | |
| # if HAVE_ACL_GET_FILE /* Linux, FreeBSD, NetBSD >= 10, Mac OS X, Cygwin >= 2.5 */ | |
| if (ctx->acl) | |
| acl_free (ctx->acl); | |
| # if !HAVE_ACL_TYPE_EXTENDED | |
| if (ctx->default_acl) | |
| acl_free (ctx->default_acl); | |
| # endif | |
| # elif defined GETACL /* Solaris, Cygwin < 2.5 */ | |
| free (ctx->entries); | |
| # ifdef ACE_GETACL | |
| free (ctx->ace_entries); | |
| # endif | |
| # elif HAVE_GETACL /* HP-UX */ | |
| # if HAVE_ACLV_H | |
| # endif | |
| # elif HAVE_STATACL /* older AIX */ | |
| # elif HAVE_ACLSORT /* NonStop Kernel */ | |
| # endif | |
| #endif | |
| } |