udev: move devnoce_acl() to udev-builtin-uaccess.c

As it is now only used by udev-builtin-uaccess.c.

This also makes devnode_acl() use fd rather than path to device node.

src/shared/devnode-acl.c

@@ -1,228 +0,0 @@
-/* SPDX-License-Identifier: LGPL-2.1-or-later */
-
-#include <errno.h>
-
-#include "sd-device.h"
-
-#include "acl-util.h"
-#include "alloc-util.h"
-#include "device-util.h"
-#include "devnode-acl.h"
-#include "dirent-util.h"
-#include "errno-util.h"
-#include "fd-util.h"
-#include "format-util.h"
-#include "fs-util.h"
-#include "glyph-util.h"
-#include "set.h"
-#include "string-util.h"
-
-static int flush_acl(acl_t acl) {
-        acl_entry_t i;
-        int found;
-        bool changed = false;
-
-        assert(acl);
-
-        for (found = acl_get_entry(acl, ACL_FIRST_ENTRY, &i);
-             found > 0;
-             found = acl_get_entry(acl, ACL_NEXT_ENTRY, &i)) {
-
-                acl_tag_t tag;
-
-                if (acl_get_tag_type(i, &tag) < 0)
-                        return -errno;
-
-                if (tag != ACL_USER)
-                        continue;
-
-                if (acl_delete_entry(acl, i) < 0)
-                        return -errno;
-
-                changed = true;
-        }
-
-        if (found < 0)
-                return -errno;
-
-        return changed;
-}
-
-int devnode_acl(const char *path,
-                bool flush,
-                bool del, uid_t old_uid,
-                bool add, uid_t new_uid) {
-
-        _cleanup_(acl_freep) acl_t acl = NULL;
-        int r;
-        bool changed = false;
-
-        assert(path);
-
-        acl = acl_get_file(path, ACL_TYPE_ACCESS);
-        if (!acl)
-                return -errno;
-
-        if (flush) {
-
-                r = flush_acl(acl);
-                if (r < 0)
-                        return r;
-                if (r > 0)
-                        changed = true;
-
-        } else if (del && old_uid > 0) {
-                acl_entry_t entry;
-
-                r = acl_find_uid(acl, old_uid, &entry);
-                if (r < 0)
-                        return r;
-
-                if (r > 0) {
-                        if (acl_delete_entry(acl, entry) < 0)
-                                return -errno;
-
-                        changed = true;
-                }
-        }
-
-        if (add && new_uid > 0) {
-                acl_entry_t entry;
-                acl_permset_t permset;
-                int rd, wt;
-
-                r = acl_find_uid(acl, new_uid, &entry);
-                if (r < 0)
-                        return r;
-
-                if (r == 0) {
-                        if (acl_create_entry(&acl, &entry) < 0)
-                                return -errno;
-
-                        if (acl_set_tag_type(entry, ACL_USER) < 0 ||
-                            acl_set_qualifier(entry, &new_uid) < 0)
-                                return -errno;
-                }
-
-                if (acl_get_permset(entry, &permset) < 0)
-                        return -errno;
-
-                rd = acl_get_perm(permset, ACL_READ);
-                if (rd < 0)
-                        return -errno;
-
-                wt = acl_get_perm(permset, ACL_WRITE);
-                if (wt < 0)
-                        return -errno;
-
-                if (!rd || !wt) {
-
-                        if (acl_add_perm(permset, ACL_READ|ACL_WRITE) < 0)
-                                return -errno;
-
-                        changed = true;
-                }
-        }
-
-        if (!changed)
-                return 0;
-
-        if (acl_calc_mask(&acl) < 0)
-                return -errno;
-
-        if (acl_set_file(path, ACL_TYPE_ACCESS, acl) < 0)
-                return -errno;
-
-        return 0;
-}
-
-int devnode_acl_all(const char *seat,
-                    bool flush,
-                    bool del, uid_t old_uid,
-                    bool add, uid_t new_uid) {
-
-        _cleanup_(sd_device_enumerator_unrefp) sd_device_enumerator *e = NULL;
-        _cleanup_set_free_ Set *nodes = NULL;
-        _cleanup_closedir_ DIR *dir = NULL;
-        char *n;
-        int r;
-
-        r = sd_device_enumerator_new(&e);
-        if (r < 0)
-                return r;
-
-        if (isempty(seat))
-                seat = "seat0";
-
-        /* We can only match by one tag in libudev. We choose
-         * "uaccess" for that. If we could match for two tags here we
-         * could add the seat name as second match tag, but this would
-         * be hardly optimizable in libudev, and hence checking the
-         * second tag manually in our loop is a good solution. */
-        r = sd_device_enumerator_add_match_tag(e, "uaccess");
-        if (r < 0)
-                return r;
-
-        FOREACH_DEVICE(e, d) {
-                const char *node, *sn;
-
-                /* Make sure the tag is still in place */
-                if (sd_device_has_current_tag(d, "uaccess") <= 0)
-                        continue;
-
-                r = device_get_seat(d, &sn);
-                if (r < 0)
-                        return r;
-
-                if (!streq(seat, sn))
-                        continue;
-
-                /* In case people mistag devices with nodes, we need to ignore this */
-                if (sd_device_get_devname(d, &node) < 0)
-                        continue;
-
-                log_device_debug(d, "Found udev node %s for seat %s", node, seat);
-                r = set_put_strdup_full(&nodes, &path_hash_ops_free, node);
-                if (r < 0)
-                        return r;
-        }
-
-        /* udev exports "dead" device nodes to allow module on-demand loading,
-         * these devices are not known to the kernel at this moment */
-        dir = opendir("/run/udev/static_node-tags/uaccess");
-        if (dir) {
-                FOREACH_DIRENT(de, dir, return -errno) {
-                        r = readlinkat_malloc(dirfd(dir), de->d_name, &n);
-                        if (r == -ENOENT)
-                                continue;
-                        if (r < 0) {
-                                log_debug_errno(r,
-                                                "Unable to read symlink '/run/udev/static_node-tags/uaccess/%s', ignoring: %m",
-                                                de->d_name);
-                                continue;
-                        }
-
-                        log_debug("Found static node %s for seat %s", n, seat);
-                        r = set_ensure_consume(&nodes, &path_hash_ops_free, n);
-                        if (r < 0)
-                                return r;
-                }
-        }
-
-        r = 0;
-        SET_FOREACH(n, nodes) {
-                int k;
-
-                log_debug("Changing ACLs at %s for seat %s (uid "UID_FMT"%s"UID_FMT"%s%s)",
-                          n, seat, old_uid, glyph(GLYPH_ARROW_RIGHT), new_uid,
-                          del ? " del" : "", add ? " add" : "");
-
-                k = devnode_acl(n, flush, del, old_uid, add, new_uid);
-                if (k == -ENOENT)
-                        log_debug("Device %s disappeared while setting ACLs", n);
-                else
-                        RET_GATHER(r, k);
-        }
-
-        return r;
-}

src/shared/devnode-acl.h

@@ -1,34 +0,0 @@
-/* SPDX-License-Identifier: LGPL-2.1-or-later */
-#pragma once
-
-#include <stdbool.h>
-#include <sys/types.h>
-
-#if HAVE_ACL
-
-int devnode_acl(const char *path,
-                bool flush,
-                bool del, uid_t old_uid,
-                bool add, uid_t new_uid);
-
-int devnode_acl_all(const char *seat,
-                    bool flush,
-                    bool del, uid_t old_uid,
-                    bool add, uid_t new_uid);
-#else
-
-static inline int devnode_acl(const char *path,
-                bool flush,
-                bool del, uid_t old_uid,
-                bool add, uid_t new_uid) {
-        return 0;
-}
-
-static inline int devnode_acl_all(const char *seat,
-                                  bool flush,
-                                  bool del, uid_t old_uid,
-                                  bool add, uid_t new_uid) {
-        return 0;
-}
-
-#endif

src/shared/meson.build

@@ -238,10 +238,6 @@ syscall_list_h = custom_target(
 
 generated_sources += syscall_list_h
 
-if conf.get('HAVE_ACL') == 1
-        shared_sources += files('devnode-acl.c')
-endif
-
 if conf.get('ENABLE_UTMP') == 1
         shared_sources += files('utmp-wtmp.c')
 endif

src/udev/udev-builtin-uaccess.c

@@ -5,12 +5,106 @@
 
 #include "sd-login.h"
 
+#include "acl-util.h"
 #include "device-util.h"
-#include "devnode-acl.h"
 #include "errno-util.h"
+#include "fd-util.h"
 #include "login-util.h"
 #include "udev-builtin.h"
 
+static int devnode_acl(int fd, uid_t uid) {
+        bool changed = false, found = false;
+        int r;
+
+        assert(fd >= 0);
+
+        _cleanup_(acl_freep) acl_t acl = NULL;
+        acl = acl_get_fd(fd);
+        if (!acl)
+                return -errno;
+
+        acl_entry_t entry;
+        for (r = acl_get_entry(acl, ACL_FIRST_ENTRY, &entry);
+             r > 0;
+             r = acl_get_entry(acl, ACL_NEXT_ENTRY, &entry)) {
+
+                acl_tag_t tag;
+                if (acl_get_tag_type(entry, &tag) < 0)
+                        return -errno;
+
+                if (tag != ACL_USER)
+                        continue;
+
+                if (uid > 0) {
+                        uid_t *u = acl_get_qualifier(entry);
+                        if (!u)
+                                return -errno;
+
+                        if (*u == uid) {
+                                acl_permset_t permset;
+                                if (acl_get_permset(entry, &permset) < 0)
+                                        return -errno;
+
+                                int rd = acl_get_perm(permset, ACL_READ);
+                                if (rd < 0)
+                                        return -errno;
+
+                                int wt = acl_get_perm(permset, ACL_WRITE);
+                                if (wt < 0)
+                                        return -errno;
+
+                                if (!rd || !wt) {
+                                        if (acl_add_perm(permset, ACL_READ|ACL_WRITE) < 0)
+                                                return -errno;
+
+                                        changed = true;
+                                }
+
+                                found = true;
+                                continue;
+                        }
+                }
+
+                if (acl_delete_entry(acl, entry) < 0)
+                        return -errno;
+
+                changed = true;
+        }
+        if (r < 0)
+                return -errno;
+
+        if (!found && uid > 0) {
+                if (acl_create_entry(&acl, &entry) < 0)
+                        return -errno;
+
+                if (acl_set_tag_type(entry, ACL_USER) < 0)
+                        return -errno;
+
+                if (acl_set_qualifier(entry, &uid) < 0)
+                        return -errno;
+
+                acl_permset_t permset;
+                if (acl_get_permset(entry, &permset) < 0)
+                        return -errno;
+
+                if (acl_add_perm(permset, ACL_READ|ACL_WRITE) < 0)
+                        return -errno;
+
+                changed = true;
+        }
+
+        if (!changed)
+                return 0;
+
+        if (acl_calc_mask(&acl) < 0)
+                return -errno;
+
+        if (acl_set_fd(fd, acl) < 0)
+                return -errno;
+
+        return 0;
+}
+
 static int builtin_uaccess(UdevEvent *event, int argc, char *argv[]) {
         sd_device *dev = ASSERT_PTR(ASSERT_PTR(event)->dev);
         int r, k;
@@ -26,10 +120,9 @@ static int builtin_uaccess(UdevEvent *event, int argc, char *argv[]) {
         if (!logind_running())
                 return 0;
 
-        const char *node;
+        _cleanup_close_ int fd = sd_device_open(dev, O_CLOEXEC|O_RDWR);
-        r = sd_device_get_devname(dev, &node);
+        if (fd < 0)
-        if (r < 0)
+                return log_device_error_errno(dev, fd, "Failed to open device node: %m");
-                return log_device_error_errno(dev, r, "Failed to get device node: %m");
 
         const char *seat;
         r = device_get_seat(dev, &seat);
@@ -48,10 +141,7 @@ static int builtin_uaccess(UdevEvent *event, int argc, char *argv[]) {
                 goto reset;
         }
 
-        r = devnode_acl(node,
+        r = devnode_acl(fd, uid);
-                        /* flush = */ true,
-                        /* del = */ false, /* old_uid = */ 0,
-                        /* add = */ true, /* new_uid = */ uid);
         if (r < 0) {
                 log_device_full_errno(dev, r == -ENOENT ? LOG_DEBUG : LOG_ERR, r, "Failed to apply ACL: %m");
                 goto reset;
@@ -61,10 +151,7 @@ static int builtin_uaccess(UdevEvent *event, int argc, char *argv[]) {
 
 reset:
         /* Better be safe than sorry and reset ACL */
-        k = devnode_acl(node,
+        k = devnode_acl(fd, /* uid = */ 0);
-                        /* flush = */ true,
-                        /* del = */ false, /* old_uid = */ 0,
-                        /* add = */ false, /* new_uid = */ 0);
         if (k < 0)
                 RET_GATHER(r, log_device_full_errno(dev, k == -ENOENT ? LOG_DEBUG : LOG_ERR, k, "Failed to flush ACLs: %m"));