Fix previous commit to properly check udev flag definition.

[platform/upstream/cryptsetup.git] / lib / libdevmapper.c

diff --git a/lib/libdevmapper.c b/lib/libdevmapper.c
index d4e9974..3d3c1a4 100644 (file)
--- a/lib/libdevmapper.c
+++ b/lib/libdevmapper.c
@@ -1,4 +1,6 @@
 #include <sys/ioctl.h>
+#include <sys/stat.h>
+#include <stdio.h>
 #include <dirent.h>
 #include <errno.h>
 #include <libdevmapper.h>
@@ -16,18 +18,24 @@
 #define DM_CRYPT_TARGET                "crypt"
 #define RETRY_COUNT            5
 
+/* Set if dm-crypt version was probed */
+static int _dm_crypt_checked = 0;
+static int _dm_crypt_wipe_key_supported = 0;
+
 static int _dm_use_count = 0;
 static struct crypt_device *_context = NULL;
 
 /* Compatibility for old device-mapper without udev support */
-#ifndef HAVE_DM_TASK_SET_COOKIE
-#define CRYPT_TEMP_UDEV_FLAGS  0
-static int dm_task_set_cookie(struct dm_task *dmt, uint32_t *cookie, uint16_t flags) { return 0; }
-static int dm_udev_wait(uint32_t cookie) { return 0; };
-#else
+#if HAVE_DECL_DM_UDEV_DISABLE_DISK_RULES_FLAG
 #define CRYPT_TEMP_UDEV_FLAGS  DM_UDEV_DISABLE_SUBSYSTEM_RULES_FLAG | \
                                DM_UDEV_DISABLE_DISK_RULES_FLAG | \
                                DM_UDEV_DISABLE_OTHER_RULES_FLAG
+#define _dm_task_set_cookie    dm_task_set_cookie
+#define _dm_udev_wait          dm_udev_wait
+#else
+#define CRYPT_TEMP_UDEV_FLAGS  0
+static int _dm_task_set_cookie(struct dm_task *dmt, uint32_t *cookie, uint16_t flags) { return 0; }
+static int _dm_udev_wait(uint32_t cookie) { return 0; };
 #endif
 
 static int _dm_use_udev()
@@ -59,13 +67,56 @@ static void set_dm_error(int level, const char *file, int line,
 
 static int _dm_simple(int task, const char *name, int udev_wait);
 
+static void _dm_set_crypt_compat(int maj, int min, int patch)
+{
+       log_dbg("Detected dm-crypt target of version %i.%i.%i.", maj, min, patch);
+
+       if (maj >= 1 && min >=2)
+               _dm_crypt_wipe_key_supported = 1;
+       else
+               log_dbg("Suspend and resume disabled, no wipe key support.");
+
+       _dm_crypt_checked = 1;
+}
+
+static int _dm_check_versions(void)
+{
+       struct dm_task *dmt;
+       struct dm_versions *target, *last_target;
+
+       if (_dm_crypt_checked)
+               return 1;
+
+       if (!(dmt = dm_task_create(DM_DEVICE_LIST_VERSIONS)))
+               return 0;
+
+       if (!dm_task_run(dmt)) {
+               dm_task_destroy(dmt);
+               return 0;
+       }
+
+       target = dm_task_get_versions(dmt);
+       do {
+               last_target = target;
+               if (!strcmp(DM_CRYPT_TARGET, target->name)) {
+                       _dm_set_crypt_compat((int)target->version[0],
+                                            (int)target->version[1],
+                                            (int)target->version[2]);
+               }
+               target = (void *) target + target->next;
+       } while (last_target != target);
+
+       dm_task_destroy(dmt);
+       return 1;
+}
+
 int dm_init(struct crypt_device *context, int check_kernel)
 {
        if (!_dm_use_count++) {
                log_dbg("Initialising device-mapper backend%s, UDEV is %sabled.",
                        check_kernel ? "" : " (NO kernel check requested)",
                        _dm_use_udev() ? "en" : "dis");
-               if (check_kernel && !_dm_simple(DM_DEVICE_LIST_VERSIONS, NULL, 0)) {
+               if (check_kernel && !_dm_check_versions()) {
                        log_err(context, _("Cannot initialize device-mapper. Is dm_mod kernel module loaded?\n"));
                        return -1;
                }
@@ -122,7 +173,7 @@ static char *__lookup_dev(char *path, dev_t dev, int dir_level, const int max_le
                        continue;
 
                strncpy(ptr, entry->d_name, space);
-               if (lstat(path, &st) < 0)
+               if (stat(path, &st) < 0)
                        continue;
 
                if (S_ISDIR(st.st_mode)) {
@@ -148,7 +199,7 @@ static char *lookup_dev(const char *dev_id)
 {
        uint32_t major, minor;
        dev_t dev;
-       char *result, buf[PATH_MAX + 1];
+       char *result = NULL, buf[PATH_MAX + 1];
 
        if (sscanf(dev_id, "%" PRIu32 ":%" PRIu32, &major, &minor) != 2)
                return NULL;
@@ -171,8 +222,8 @@ static char *lookup_dev(const char *dev_id)
        strncpy(buf, DEVICE_DIR, PATH_MAX);
        result = __lookup_dev(buf, dev, 0, 4);
 
-       /* If not found, return major:minor */
-       return result ?: strdup(dev_id);
+       /* If not found, return NULL */
+       return result;
 }
 
 static int _dev_read_ahead(const char *dev, uint32_t *read_ahead)
@@ -240,13 +291,13 @@ static int _dm_simple(int task, const char *name, int udev_wait)
        if (name && !dm_task_set_name(dmt, name))
                goto out;
 
-       if (udev_wait && !dm_task_set_cookie(dmt, &cookie, 0))
+       if (udev_wait && !_dm_task_set_cookie(dmt, &cookie, 0))
                goto out;
 
        r = dm_task_run(dmt);
 
        if (udev_wait)
-               (void)dm_udev_wait(cookie);
+               (void)_dm_udev_wait(cookie);
 
       out:
        dm_task_destroy(dmt);
@@ -406,7 +457,7 @@ int dm_create_device(const char *name,
                if (!dm_task_set_uuid(dmt, dev_uuid))
                        goto out_no_removal;
 
-               if (_dm_use_udev() && !dm_task_set_cookie(dmt, &cookie, udev_flags))
+               if (_dm_use_udev() && !_dm_task_set_cookie(dmt, &cookie, udev_flags))
                        goto out_no_removal;
        }
 
@@ -432,7 +483,7 @@ int dm_create_device(const char *name,
                        goto out;
                if (uuid && !dm_task_set_uuid(dmt, dev_uuid))
                        goto out;
-               if (_dm_use_udev() && !dm_task_set_cookie(dmt, &cookie, udev_flags))
+               if (_dm_use_udev() && !_dm_task_set_cookie(dmt, &cookie, udev_flags))
                        goto out;
                if (!dm_task_run(dmt))
                        goto out;
@@ -444,7 +495,7 @@ int dm_create_device(const char *name,
        r = 0;
 out:
        if (_dm_use_udev()) {
-               (void)dm_udev_wait(cookie);
+               (void)_dm_udev_wait(cookie);
                cookie = 0;
        }
 
@@ -462,7 +513,7 @@ out:
 
 out_no_removal:
        if (cookie && _dm_use_udev())
-               (void)dm_udev_wait(cookie);
+               (void)_dm_udev_wait(cookie);
 
        if (params)
                safe_free(params);
@@ -663,6 +714,12 @@ static int _dm_message(const char *name, const char *msg)
 
 int dm_suspend_and_wipe_key(const char *name)
 {
+       if (!_dm_check_versions())
+               return -ENOTSUP;
+
+       if (!_dm_crypt_wipe_key_supported)
+               return -ENOTSUP;
+
        if (!_dm_simple(DM_DEVICE_SUSPEND, name, 0))
                return -EINVAL;
 
@@ -682,6 +739,12 @@ int dm_resume_and_reinstate_key(const char *name,
        char *msg;
        int r = 0;
 
+       if (!_dm_check_versions())
+               return -ENOTSUP;
+
+       if (!_dm_crypt_wipe_key_supported)
+               return -ENOTSUP;
+
        msg = safe_alloc(msg_size);
        if (!msg)
                return -ENOMEM;