shared/acl-util: add mask only when needed, always add base ACLs

[elogind.git] / src / shared / acl-util.c

diff --git a/src/shared/acl-util.c b/src/shared/acl-util.c
index fb04e49dc4367e74454bb9996b23823c42b4f926..a4ff1ab878e12aa3d2bff6dfc0cdbe22c5b47619 100644 (file)
--- a/src/shared/acl-util.c
+++ b/src/shared/acl-util.c
@@ -20,8 +20,6 @@
 ***/
 
 #include <assert.h>
-#include <sys/acl.h>
-#include <acl/libacl.h>
 #include <errno.h>
 #include <stdbool.h>
 
@@ -31,14 +29,14 @@
 
 int acl_find_uid(acl_t acl, uid_t uid, acl_entry_t *entry) {
         acl_entry_t i;
-        int found;
+        int r;
 
         assert(acl);
         assert(entry);
 
-        for (found = acl_get_entry(acl, ACL_FIRST_ENTRY, &i);
-             found > 0;
-             found = acl_get_entry(acl, ACL_NEXT_ENTRY, &i)) {
+        for (r = acl_get_entry(acl, ACL_FIRST_ENTRY, &i);
+             r > 0;
+             r = acl_get_entry(acl, ACL_NEXT_ENTRY, &i)) {
 
                 acl_tag_t tag;
                 uid_t *u;
@@ -62,8 +60,7 @@ int acl_find_uid(acl_t acl, uid_t uid, acl_entry_t *entry) {
                         return 1;
                 }
         }
-
-        if (found < 0)
+        if (r < 0)
                 return -errno;
 
         return 0;
@@ -71,14 +68,13 @@ int acl_find_uid(acl_t acl, uid_t uid, acl_entry_t *entry) {
 
 int calc_acl_mask_if_needed(acl_t *acl_p) {
         acl_entry_t i;
-        int found;
+        int r;
 
         assert(acl_p);
 
-        for (found = acl_get_entry(*acl_p, ACL_FIRST_ENTRY, &i);
-             found > 0;
-             found = acl_get_entry(*acl_p, ACL_NEXT_ENTRY, &i)) {
-
+        for (r = acl_get_entry(*acl_p, ACL_FIRST_ENTRY, &i);
+             r > 0;
+             r = acl_get_entry(*acl_p, ACL_NEXT_ENTRY, &i)) {
                 acl_tag_t tag;
 
                 if (acl_get_tag_type(i, &tag) < 0)
@@ -86,14 +82,80 @@ int calc_acl_mask_if_needed(acl_t *acl_p) {
 
                 if (tag == ACL_MASK)
                         return 0;
+                if (IN_SET(tag, ACL_USER, ACL_GROUP))
+                        goto calc;
         }
-
-        if (found < 0)
+        if (r < 0)
                 return -errno;
+        return 0;
 
+calc:
         if (acl_calc_mask(acl_p) < 0)
                 return -errno;
+        return 1;
+}
+
+int add_base_acls_if_needed(acl_t *acl_p, const char *path) {
+        acl_entry_t i;
+        int r;
+        bool have_user_obj = false, have_group_obj = false, have_other = false;
+        struct stat st;
+        _cleanup_(acl_freep) acl_t basic = NULL;
+
+        assert(acl_p);
+
+        for (r = acl_get_entry(*acl_p, ACL_FIRST_ENTRY, &i);
+             r > 0;
+             r = acl_get_entry(*acl_p, ACL_NEXT_ENTRY, &i)) {
+                acl_tag_t tag;
+
+                if (acl_get_tag_type(i, &tag) < 0)
+                        return -errno;
+
+                if (tag == ACL_USER_OBJ)
+                        have_user_obj = true;
+                else if (tag == ACL_GROUP_OBJ)
+                        have_group_obj = true;
+                else if (tag == ACL_OTHER)
+                        have_other = true;
+                if (have_user_obj && have_group_obj && have_other)
+                        return 0;
+        }
+        if (r < 0)
+                return -errno;
 
+        r = stat(path, &st);
+        if (r < 0)
+                return -errno;
+
+        basic = acl_from_mode(st.st_mode);
+        if (!basic)
+                return -errno;
+
+        for (r = acl_get_entry(basic, ACL_FIRST_ENTRY, &i);
+             r > 0;
+             r = acl_get_entry(basic, ACL_NEXT_ENTRY, &i)) {
+                acl_tag_t tag;
+                acl_entry_t dst;
+
+                if (acl_get_tag_type(i, &tag) < 0)
+                        return -errno;
+
+                if ((tag == ACL_USER_OBJ && have_user_obj) ||
+                    (tag == ACL_GROUP_OBJ && have_group_obj) ||
+                    (tag == ACL_OTHER && have_other))
+                        continue;
+
+                r = acl_create_entry(acl_p, &dst);
+                if (r < 0)
+                        return -errno;
+
+                r = acl_copy_entry(dst, i);
+                if (r < 0)
+                        return -errno;
+        }
+        if (r < 0)
+                return -errno;
         return 0;
 }
 
@@ -136,9 +198,8 @@ int search_acl_groups(char*** dst, const char* path, bool* belong) {
                                 return log_oom();
                         }
 
-                        r = strv_push(dst, name);
+                        r = strv_consume(dst, name);
                         if (r < 0) {
-                                free(name);
                                 acl_free(acl);
                                 return log_oom();
                         }
@@ -152,3 +213,100 @@ int search_acl_groups(char*** dst, const char* path, bool* belong) {
 
         return 0;
 }
+
+int parse_acl(char *text, acl_t *acl_access, acl_t *acl_default, bool want_mask) {
+        _cleanup_free_ char **a = NULL, **d = NULL; /* strings are not be freed */
+        _cleanup_strv_free_ char **split;
+        char **entry;
+        int r = -EINVAL;
+        _cleanup_(acl_freep) acl_t a_acl = NULL, d_acl = NULL;
+
+        split = strv_split(text, ",");
+        if (!split)
+                return log_oom();
+
+        STRV_FOREACH(entry, split) {
+                char *p;
+
+                p = startswith(*entry, "default:");
+                if (!p)
+                        p = startswith(*entry, "d:");
+
+                if (p)
+                        r = strv_push(&d, p);
+                else
+                        r = strv_push(&a, *entry);
+        }
+        if (r < 0)
+                return r;
+
+        if (!strv_isempty(a)) {
+                _cleanup_free_ char *join;
+
+                join = strv_join(a, ",");
+                if (!join)
+                        return -ENOMEM;
+
+                a_acl = acl_from_text(join);
+                if (!a_acl)
+                        return -EINVAL;
+
+                if (want_mask) {
+                        r = calc_acl_mask_if_needed(&a_acl);
+                        if (r < 0)
+                                return r;
+                }
+        }
+
+        if (!strv_isempty(d)) {
+                _cleanup_free_ char *join;
+
+                join = strv_join(d, ",");
+                if (!join)
+                        return -ENOMEM;
+
+                d_acl = acl_from_text(join);
+                if (!d_acl)
+                        return -EINVAL;
+
+                if (want_mask) {
+                        r = calc_acl_mask_if_needed(&d_acl);
+                        if (r < 0)
+                                return r;
+                }
+        }
+
+        *acl_access = a_acl;
+        *acl_default = d_acl;
+        a_acl = d_acl = NULL;
+        return 0;
+}
+
+int acls_for_file(const char *path, acl_type_t type, acl_t new, acl_t *acl) {
+        _cleanup_(acl_freep) acl_t old;
+        acl_entry_t i;
+        int r;
+
+        old = acl_get_file(path, type);
+        if (!old)
+                return -errno;
+
+        for (r = acl_get_entry(new, ACL_FIRST_ENTRY, &i);
+             r > 0;
+             r = acl_get_entry(new, ACL_NEXT_ENTRY, &i)) {
+
+                acl_entry_t j;
+
+                if (acl_create_entry(&old, &j) < 0)
+                        return -errno;
+
+                if (acl_copy_entry(j, i) < 0)
+                        return -errno;
+        }
+        if (r < 0)
+                return -errno;
+
+        *acl = old;
+        old = NULL;
+        return 0;
+}