#include <errno.h>
+#include <libgen.h> /* dirname() */
#include <limits.h> /* PATH_MAX */
#include <stdbool.h>
#include <stdio.h>
#include <stdlib.h>
+#include <string.h>
+#include <sys/stat.h>
+#include <unistd.h>
/* ACLs */
+#include <acl/libacl.h> /* acl_get_perm, not portable */
#include <sys/types.h>
#include <sys/acl.h>
-bool has_default_acl(const char* path) {
- /* Return true if the given path has a default ACL, false
- otherwise. */
- acl_t defacl = acl_get_file(path, ACL_TYPE_DEFAULT);
-
- if (defacl == (acl_t)NULL) {
+
+mode_t get_mode(const char* path) {
+ if (path == NULL) {
+ errno = ENOENT;
+ return -1;
+ }
+
+ struct stat s;
+ int result = stat(path, &s);
+
+ if (result == 0) {
+ return s.st_mode;
+ }
+ else {
+ /* errno will be set already by stat() */
+ return result;
+ }
+}
+
+
+bool is_regular_file(const char* path) {
+ if (path == NULL) {
return false;
}
- /* Used to store the entry if it exists, even though we don't care
- what it is. */
- acl_entry_t dummy;
-
- int result = acl_get_entry(defacl, ACL_FIRST_ENTRY, &dummy);
-
- if (result == 1) {
- /* There's a first entry in the default ACL. */
- return true;
+ struct stat s;
+ int result = stat(path, &s);
+ if (result == 0) {
+ return S_ISREG(s.st_mode);
}
- else if (result == 0) {
+ else {
+ return false;
+ }
+}
+
+bool is_directory(const char* path) {
+ if (path == NULL) {
return false;
}
+
+ struct stat s;
+ int result = stat(path, &s);
+ if (result == 0) {
+ return S_ISDIR(s.st_mode);
+ }
else {
- perror("has_default_acl");
return false;
}
}
-bool has_default_tag_acl(const char* path, acl_tag_t tag_type) {
- /* Return true if the given path has a default ACL for the supplied
- tag, false otherwise. */
- acl_t defacl = acl_get_file(path, ACL_TYPE_DEFAULT);
-
- if (defacl == (acl_t)NULL) {
- return false;
+int acl_set_entry(acl_t* aclp,
+ acl_entry_t entry) {
+ /* Update or create the given entry. */
+
+ acl_tag_t entry_tag;
+ int gt_result = acl_get_tag_type(entry, &entry_tag);
+ if (gt_result == -1) {
+ perror("acl_set_entry (acl_get_tag_type)");
+ return -1;
}
- acl_entry_t entry;
- int result = acl_get_entry(defacl, ACL_FIRST_ENTRY, &entry);
+ acl_permset_t entry_permset;
+ int ps_result = acl_get_permset(entry, &entry_permset);
+ if (ps_result == -1) {
+ perror("acl_set_entry (acl_get_permset)");
+ return -1;
+ }
+
+ acl_entry_t existing_entry;
+ /* Loop through the given ACL looking for matching entries. */
+ int result = acl_get_entry(*aclp, ACL_FIRST_ENTRY, &existing_entry);
while (result == 1) {
- acl_tag_t tag = ACL_UNDEFINED_TAG;
- int tag_result = acl_get_tag_type(entry, &tag);
-
+ acl_tag_t existing_tag = ACL_UNDEFINED_TAG;
+ int tag_result = acl_get_tag_type(existing_entry, &existing_tag);
+
if (tag_result == -1) {
- perror("has_default_tag_acl");
- return false;
+ perror("set_acl_tag_permset (acl_get_tag_type)");
+ return -1;
}
- else {
- if (tag == tag_type) {
- return true;
+
+ if (existing_tag == entry_tag) {
+ if (entry_tag == ACL_USER_OBJ ||
+ entry_tag == ACL_GROUP_OBJ ||
+ entry_tag == ACL_OTHER) {
+ /* Only update for these three since all other tags will have
+ been wiped. */
+ acl_permset_t existing_permset;
+ int gep_result = acl_get_permset(existing_entry, &existing_permset);
+ if (gep_result == -1) {
+ perror("acl_set_entry (acl_get_permset)");
+ return -1;
+ }
+
+ int s_result = acl_set_permset(existing_entry, entry_permset);
+ if (s_result == -1) {
+ perror("acl_set_entry (acl_set_permset)");
+ return -1;
+ }
+
+ return 1;
}
+
+ }
+
+ result = acl_get_entry(*aclp, ACL_NEXT_ENTRY, &existing_entry);
+ }
+
+ /* This catches both the initial acl_get_entry and the ones at the
+ end of the loop. */
+ if (result == -1) {
+ perror("acl_set_entry (acl_get_entry)");
+ return -1;
+ }
+
+ /* If we've made it this far, we need to add a new entry to the
+ ACL. */
+ acl_entry_t new_entry;
+
+ /* We allocate memory here that we should release! */
+ int c_result = acl_create_entry(aclp, &new_entry);
+ if (c_result == -1) {
+ perror("acl_set_entry (acl_create_entry)");
+ return -1;
+ }
+
+ int st_result = acl_set_tag_type(new_entry, entry_tag);
+ if (st_result == -1) {
+ perror("acl_set_entry (acl_set_tag_type)");
+ return -1;
+ }
+
+ int s_result = acl_set_permset(new_entry, entry_permset);
+ if (s_result == -1) {
+ perror("acl_set_entry (acl_set_permset)");
+ return -1;
+ }
+
+ if (entry_tag == ACL_USER || entry_tag == ACL_GROUP) {
+ /* We need to set the qualifier too. */
+ void* entry_qual = acl_get_qualifier(entry);
+ if (entry_qual == (void*)NULL) {
+ perror("acl_set_entry (acl_get_qualifier)");
+ return -1;
+ }
+
+ int sq_result = acl_set_qualifier(new_entry, entry_qual);
+ if (sq_result == -1) {
+ perror("acl_set_entry (acl_set_qualifier)");
+ return -1;
}
-
- result = acl_get_entry(defacl, ACL_NEXT_ENTRY, &entry);
}
-
- return false;
+
+ return 1;
}
-bool has_default_user_obj_acl(const char* path) {
- return has_default_tag_acl(path, ACL_USER_OBJ);
+
+int acl_entry_count(acl_t* acl) {
+ /* Return the number of entries in ACL, or -1 on error. */
+ acl_entry_t entry;
+ int entry_count = 0;
+ int result = acl_get_entry(*acl, ACL_FIRST_ENTRY, &entry);
+
+ while (result == 1) {
+ entry_count++;
+ result = acl_get_entry(*acl, ACL_NEXT_ENTRY, &entry);
+ }
+
+ if (result == -1) {
+ perror("acl_is_minimal (acl_get_entry)");
+ return -1;
+ }
+
+ return entry_count;
}
-bool has_default_group_obj_acl(const char* path) {
- return has_default_tag_acl(path, ACL_GROUP_OBJ);
+
+int acl_is_minimal(acl_t* acl) {
+ /* An ACL is minimal if it has fewer than four entries. Return 0 for
+ false, 1 for true, and -1 on error. */
+
+ int ec = acl_entry_count(acl);
+ if (ec == -1) {
+ perror("acl_is_minimal (acl_entry_count)");
+ return -1;
+ }
+
+ if (ec < 4) {
+ return 1;
+ }
+ else {
+ return 0;
+ }
}
-bool has_default_other_obj_acl(const char* path) {
- return has_default_tag_acl(path, ACL_OTHER);
+
+int any_can_execute(const char* path) {
+ /* Returns 1 if any ACL entry has execute access, 0 if none do, and
+ -1 on error. */
+ acl_t acl = acl_get_file(path, ACL_TYPE_ACCESS);
+
+ if (acl == (acl_t)NULL) {
+ return 0;
+ }
+
+ /* Our return value. */
+ int result = 0;
+
+ if (acl_is_minimal(&acl)) {
+ mode_t mode = get_mode(path);
+ if (mode & (S_IXUSR | S_IXOTH | S_IXGRP)) {
+ result = 1;
+ goto cleanup;
+ }
+ else {
+ result = 0;
+ goto cleanup;
+ }
+ }
+
+ acl_entry_t entry;
+ int ge_result = acl_get_entry(acl, ACL_FIRST_ENTRY, &entry);
+
+ while (ge_result == 1) {
+ acl_permset_t permset;
+
+ int ps_result = acl_get_permset(entry, &permset);
+ if (ps_result == -1) {
+ perror("any_can_execute (acl_get_permset)");
+ result = -1;
+ goto cleanup;
+ }
+
+ int gp_result = acl_get_perm(permset, ACL_EXECUTE);
+ if (gp_result == -1) {
+ perror("any_can_execute (acl_get_perm)");
+ result = -1;
+ goto cleanup;
+ }
+
+ if (gp_result == 1) {
+ result = 1;
+ goto cleanup;
+ }
+
+ ge_result = acl_get_entry(acl, ACL_NEXT_ENTRY, &entry);
+ }
+
+ if (ge_result == -1) {
+ perror("any_can_execute (acl_get_entry)");
+ result = -1;
+ goto cleanup;
+ }
+
+ cleanup:
+ acl_free(acl);
+ return result;
+}
+
+
+int inherit_default_acl(const char* path, const char* parent) {
+ /* Inherit the default ACL from parent to path. This overwrites any
+ existing default ACL. Returns 1 for success, 0 for failure, and
+ -1 on error. */
+
+ /* Our return value. */
+ int result = 1;
+
+ if (path == NULL) {
+ errno = ENOENT;
+ return -1;
+ }
+
+ if (!is_directory(path) || !is_directory(parent)) {
+ return 0;
+ }
+
+ acl_t parent_acl = acl_get_file(parent, ACL_TYPE_DEFAULT);
+ if (parent_acl == (acl_t)NULL) {
+ return 0;
+ }
+
+ acl_t path_acl = acl_dup(parent_acl);
+
+ if (path_acl == (acl_t)NULL) {
+ perror("inherit_default_acl (acl_dup)");
+ acl_free(parent_acl);
+ return -1;
+ }
+
+ int sf_result = acl_set_file(path, ACL_TYPE_DEFAULT, path_acl);
+ if (sf_result == -1) {
+ perror("inherit_default_acl (acl_set_file)");
+ result = -1;
+ goto cleanup;
+ }
+
+ cleanup:
+ acl_free(path_acl);
+ return result;
+}
+
+
+int wipe_acls(const char* path) {
+ /* Remove ACL_USER, ACL_GROUP, and ACL_MASK entries from
+ path. Returns 1 for success, 0 for failure, and -1 on error. */
+
+ if (path == NULL) {
+ errno = ENOENT;
+ return -1;
+ }
+
+ /* Finally, remove individual named/mask entries. */
+ acl_t acl = acl_get_file(path, ACL_TYPE_ACCESS);
+ if (acl == (acl_t)NULL) {
+ perror("wipe_acls (acl_get_file)");
+ return -1;
+ }
+
+ /* Our return value. */
+ int result = 1;
+
+ acl_entry_t entry;
+ int ge_result = acl_get_entry(acl, ACL_FIRST_ENTRY, &entry);
+
+ while (ge_result == 1) {
+ int d_result = acl_delete_entry(acl, entry);
+ if (d_result == -1) {
+ perror("wipe_acls (acl_delete_entry)");
+ result = -1;
+ goto cleanup;
+ }
+
+ ge_result = acl_get_entry(acl, ACL_NEXT_ENTRY, &entry);
+ }
+
+ /* Catches the first acl_get_entry as well as the ones at the end of
+ the loop. */
+ if (ge_result == -1) {
+ perror("wipe_acls (acl_get_entry)");
+ result = -1;
+ goto cleanup;
+ }
+
+ int sf_result = acl_set_file(path, ACL_TYPE_ACCESS, acl);
+ if (sf_result == -1) {
+ perror("wipe_acls (acl_set_file)");
+ result = -1;
+ goto cleanup;
+ }
+
+ cleanup:
+ acl_free(acl);
+ return result;
}
-int get_default_tag_permset(const char* path,
- acl_tag_t tag_type,
- acl_permset_t* output_perms) {
- /* Return true if the given path has a default ACL for the supplied
- tag, false otherwise. */
- acl_t defacl = acl_get_file(path, ACL_TYPE_DEFAULT);
-
+int reapply_default_acl(const char* path) {
+ /* Really reapply the default ACL by looping through it. Returns one
+ for success, zero for failure (i.e. no ACL), and -1 on unexpected
+ errors. */
+ if (path == NULL) {
+ return 0;
+ }
+
+ if (!is_regular_file(path) && !is_directory(path)) {
+ return 0;
+ }
+
+ /* dirname mangles its argument */
+ char path_copy[PATH_MAX];
+ strncpy(path_copy, path, PATH_MAX-1);
+ path_copy[PATH_MAX-1] = 0;
+
+ char* parent = dirname(path_copy);
+ if (!is_directory(parent)) {
+ /* Make sure dirname() did what we think it did. */
+ return 0;
+ }
+
+ int ace_result = any_can_execute(path);
+ if (ace_result == -1) {
+ perror("reapply_default_acl_ng (any_can_execute)");
+ return -1;
+ }
+
+ bool allow_exec = (bool)ace_result;
+
+ acl_t defacl = acl_get_file(parent, ACL_TYPE_DEFAULT);
+
if (defacl == (acl_t)NULL) {
- /* Follow the acl_foo convention of -1 == error. */
+ perror("reapply_default_acl_ng (acl_get_file)");
return -1;
}
+ /* Our return value. */
+ int result = 1;
+
+ int wipe_result = wipe_acls(path);
+ if (wipe_result == -1) {
+ perror("reapply_default_acl_ng (wipe_acls)");
+ result = -1;
+ goto cleanup;
+ }
+
+ /* Do this after wipe_acls(), otherwise we'll overwrite the wiped
+ ACL with this one. */
+ acl_t acl = acl_get_file(path, ACL_TYPE_ACCESS);
+ if (acl == (acl_t)NULL) {
+ perror("reapply_default_acl_ng (acl_get_file)");
+ return -1;
+ }
+
+ /* If it's a directory, inherit the parent's default. */
+ int inherit_result = inherit_default_acl(path, parent);
+ if (inherit_result == -1) {
+ perror("reapply_default_acl_ng (inherit_acls)");
+ result = -1;
+ goto cleanup;
+ }
+
acl_entry_t entry;
- int result = acl_get_entry(defacl, ACL_FIRST_ENTRY, &entry);
+ int ge_result = acl_get_entry(defacl, ACL_FIRST_ENTRY, &entry);
- while (result == 1) {
+ while (ge_result == 1) {
acl_tag_t tag = ACL_UNDEFINED_TAG;
int tag_result = acl_get_tag_type(entry, &tag);
-
+
if (tag_result == -1) {
- perror("get_default_tag_permset");
- return -1;
+ perror("has_default_tag_acl (acl_get_tag_type)");
+ result = -1;
+ goto cleanup;
}
- else {
- if (tag == tag_type) {
- /* We found the right tag, now get the permset. */
- return acl_get_permset(entry, output_perms);
+
+
+ /* We've got an entry/tag from the default ACL. Get its permset. */
+ acl_permset_t permset;
+ int ps_result = acl_get_permset(entry, &permset);
+ if (ps_result == -1) {
+ perror("reapply_default_acl_ng (acl_get_permset)");
+ result = -1;
+ goto cleanup;
+ }
+
+ /* If this is a default mask, fix it up. */
+ if (tag == ACL_MASK ||
+ tag == ACL_USER_OBJ ||
+ tag == ACL_GROUP_OBJ ||
+ tag == ACL_OTHER) {
+ if (!allow_exec) {
+ /* The mask doesn't affect acl_user_obj, acl_group_obj (in
+ minimal ACLs) or acl_other entries, so if execute should be
+ masked, we have to do it manually. */
+ int d_result = acl_delete_perm(permset, ACL_EXECUTE);
+ if (d_result == -1) {
+ perror("reapply_default_acl_ng (acl_delete_perm)");
+ result = -1;
+ goto cleanup;
+ }
+
+ int sp_result = acl_set_permset(entry, permset);
+ if (sp_result == -1) {
+ perror("reapply_default_acl_ng (acl_set_permset)");
+ result = -1;
+ goto cleanup;
+ }
}
}
-
- result = acl_get_entry(defacl, ACL_NEXT_ENTRY, &entry);
+
+ /* Finally, add the permset to the access ACL. */
+ int set_result = acl_set_entry(&acl, entry);
+ if (set_result == -1) {
+ perror("reapply_default_acl_ng (acl_set_entry)");
+ result = -1;
+ goto cleanup;
+ }
+
+ ge_result = acl_get_entry(defacl, ACL_NEXT_ENTRY, &entry);
}
-
- return false;
-}
-int get_default_user_obj_permset(const char* path,
- acl_permset_t* output_perms) {
- return get_default_tag_permset(path, ACL_USER_OBJ, output_perms);
-}
+ /* Catches the first acl_get_entry as well as the ones at the end of
+ the loop. */
+ if (ge_result == -1) {
+ perror("reapply_default_acl_ng (acl_get_entry)");
+ result = -1;
+ goto cleanup;
+ }
-int get_default_group_obj_permset(const char* path,
- acl_permset_t* output_perms) {
- return get_default_tag_permset(path, ACL_GROUP_OBJ, output_perms);
-}
+ int sf_result = acl_set_file(path, ACL_TYPE_ACCESS, acl);
+ if (sf_result == -1) {
+ perror("reapply_default_acl_ng (acl_set_file)");
+ result = -1;
+ goto cleanup;
+ }
-int get_default_other_obj_permset(const char* path,
- acl_permset_t* output_perms) {
- return get_default_tag_permset(path, ACL_OTHER, output_perms);
+ cleanup:
+ acl_free(defacl);
+ return result;
}
+
int main(int argc, char* argv[]) {
const char* target = argv[1];
- printf("Target: %s\n", target);
-
- if (has_default_acl(target)) {
- printf("Target has a default ACL.\n");
- }
- else {
- printf("Target does not have a default ACL.\n");
- }
- if (has_default_user_obj_acl(target)) {
- printf("Target has a default owner ACL.\n");
- acl_permset_t owner_perms;
- get_default_user_obj_permset(target, &owner_perms);
- if (acl_get_perm(owner_perms, ACL_READ) == 1) {
- printf("User: read\n");
- }
- if (acl_get_perm(owner_perms, ACL_WRITE) == 1) {
- printf("User: write\n");
- }
- if (acl_get_perm(owner_perms, ACL_EXECUTE) == 1) {
- printf("User: execute\n");
- }
- }
- else {
- printf("Target does not have a default owner ACL.\n");
- }
-
- if (has_default_group_obj_acl(target)) {
- printf("Target has a default group ACL.\n");
- }
- else {
- printf("Target does not have a default group ACL.\n");
- }
+ bool result = reapply_default_acl(target);
- if (has_default_other_obj_acl(target)) {
- printf("Target has a default other ACL.\n");
+ if (result) {
+ return EXIT_SUCCESS;
}
else {
- printf("Target does not have a default other ACL.\n");
+ return EXIT_FAILURE;
}
- /*
- acl_permset_t group_perms;
- get_default_group_obj_permset();
-
- acl_permset_t other_perms;
- get_default_other_obj_permset();
- */
- return EXIT_SUCCESS;
}
projects / apply-default-acl.git / blobdiff