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path: root/drivers/platform/x86/dell-smbios-base.c
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Diffstat (limited to 'drivers/platform/x86/dell-smbios-base.c')
-rw-r--r--drivers/platform/x86/dell-smbios-base.c648
1 files changed, 648 insertions, 0 deletions
diff --git a/drivers/platform/x86/dell-smbios-base.c b/drivers/platform/x86/dell-smbios-base.c
new file mode 100644
index 000000000000..5bcf8a18f785
--- /dev/null
+++ b/drivers/platform/x86/dell-smbios-base.c
@@ -0,0 +1,648 @@
+/*
+ * Common functions for kernel modules using Dell SMBIOS
+ *
+ * Copyright (c) Red Hat <mjg@redhat.com>
+ * Copyright (c) 2014 Gabriele Mazzotta <gabriele.mzt@gmail.com>
+ * Copyright (c) 2014 Pali Rohár <pali.rohar@gmail.com>
+ *
+ * Based on documentation in the libsmbios package:
+ * Copyright (C) 2005-2014 Dell Inc.
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 as
+ * published by the Free Software Foundation.
+ */
+#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
+
+#include <linux/kernel.h>
+#include <linux/module.h>
+#include <linux/capability.h>
+#include <linux/dmi.h>
+#include <linux/err.h>
+#include <linux/mutex.h>
+#include <linux/platform_device.h>
+#include <linux/slab.h>
+#include "dell-smbios.h"
+
+static u32 da_supported_commands;
+static int da_num_tokens;
+static struct platform_device *platform_device;
+static struct calling_interface_token *da_tokens;
+static struct device_attribute *token_location_attrs;
+static struct device_attribute *token_value_attrs;
+static struct attribute **token_attrs;
+static DEFINE_MUTEX(smbios_mutex);
+
+struct smbios_device {
+ struct list_head list;
+ struct device *device;
+ int (*call_fn)(struct calling_interface_buffer *arg);
+};
+
+struct smbios_call {
+ u32 need_capability;
+ int cmd_class;
+ int cmd_select;
+};
+
+/* calls that are whitelisted for given capabilities */
+static struct smbios_call call_whitelist[] = {
+ /* generally tokens are allowed, but may be further filtered or
+ * restricted by token blacklist or whitelist
+ */
+ {CAP_SYS_ADMIN, CLASS_TOKEN_READ, SELECT_TOKEN_STD},
+ {CAP_SYS_ADMIN, CLASS_TOKEN_READ, SELECT_TOKEN_AC},
+ {CAP_SYS_ADMIN, CLASS_TOKEN_READ, SELECT_TOKEN_BAT},
+ {CAP_SYS_ADMIN, CLASS_TOKEN_WRITE, SELECT_TOKEN_STD},
+ {CAP_SYS_ADMIN, CLASS_TOKEN_WRITE, SELECT_TOKEN_AC},
+ {CAP_SYS_ADMIN, CLASS_TOKEN_WRITE, SELECT_TOKEN_BAT},
+ /* used by userspace: fwupdate */
+ {CAP_SYS_ADMIN, CLASS_ADMIN_PROP, SELECT_ADMIN_PROP},
+ /* used by userspace: fwupd */
+ {CAP_SYS_ADMIN, CLASS_INFO, SELECT_DOCK},
+ {CAP_SYS_ADMIN, CLASS_FLASH_INTERFACE, SELECT_FLASH_INTERFACE},
+};
+
+/* calls that are explicitly blacklisted */
+static struct smbios_call call_blacklist[] = {
+ {0x0000, 1, 7}, /* manufacturing use */
+ {0x0000, 6, 5}, /* manufacturing use */
+ {0x0000, 11, 3}, /* write once */
+ {0x0000, 11, 7}, /* write once */
+ {0x0000, 11, 11}, /* write once */
+ {0x0000, 19, -1}, /* diagnostics */
+ /* handled by kernel: dell-laptop */
+ {0x0000, CLASS_INFO, SELECT_RFKILL},
+ {0x0000, CLASS_KBD_BACKLIGHT, SELECT_KBD_BACKLIGHT},
+};
+
+struct token_range {
+ u32 need_capability;
+ u16 min;
+ u16 max;
+};
+
+/* tokens that are whitelisted for given capabilities */
+static struct token_range token_whitelist[] = {
+ /* used by userspace: fwupdate */
+ {CAP_SYS_ADMIN, CAPSULE_EN_TOKEN, CAPSULE_DIS_TOKEN},
+ /* can indicate to userspace that WMI is needed */
+ {0x0000, WSMT_EN_TOKEN, WSMT_DIS_TOKEN}
+};
+
+/* tokens that are explicitly blacklisted */
+static struct token_range token_blacklist[] = {
+ {0x0000, 0x0058, 0x0059}, /* ME use */
+ {0x0000, 0x00CD, 0x00D0}, /* raid shadow copy */
+ {0x0000, 0x013A, 0x01FF}, /* sata shadow copy */
+ {0x0000, 0x0175, 0x0176}, /* write once */
+ {0x0000, 0x0195, 0x0197}, /* diagnostics */
+ {0x0000, 0x01DC, 0x01DD}, /* manufacturing use */
+ {0x0000, 0x027D, 0x0284}, /* diagnostics */
+ {0x0000, 0x02E3, 0x02E3}, /* manufacturing use */
+ {0x0000, 0x02FF, 0x02FF}, /* manufacturing use */
+ {0x0000, 0x0300, 0x0302}, /* manufacturing use */
+ {0x0000, 0x0325, 0x0326}, /* manufacturing use */
+ {0x0000, 0x0332, 0x0335}, /* fan control */
+ {0x0000, 0x0350, 0x0350}, /* manufacturing use */
+ {0x0000, 0x0363, 0x0363}, /* manufacturing use */
+ {0x0000, 0x0368, 0x0368}, /* manufacturing use */
+ {0x0000, 0x03F6, 0x03F7}, /* manufacturing use */
+ {0x0000, 0x049E, 0x049F}, /* manufacturing use */
+ {0x0000, 0x04A0, 0x04A3}, /* disagnostics */
+ {0x0000, 0x04E6, 0x04E7}, /* manufacturing use */
+ {0x0000, 0x4000, 0x7FFF}, /* internal BIOS use */
+ {0x0000, 0x9000, 0x9001}, /* internal BIOS use */
+ {0x0000, 0xA000, 0xBFFF}, /* write only */
+ {0x0000, 0xEFF0, 0xEFFF}, /* internal BIOS use */
+ /* handled by kernel: dell-laptop */
+ {0x0000, BRIGHTNESS_TOKEN, BRIGHTNESS_TOKEN},
+ {0x0000, KBD_LED_OFF_TOKEN, KBD_LED_AUTO_TOKEN},
+ {0x0000, KBD_LED_AC_TOKEN, KBD_LED_AC_TOKEN},
+ {0x0000, KBD_LED_AUTO_25_TOKEN, KBD_LED_AUTO_75_TOKEN},
+ {0x0000, KBD_LED_AUTO_100_TOKEN, KBD_LED_AUTO_100_TOKEN},
+ {0x0000, GLOBAL_MIC_MUTE_ENABLE, GLOBAL_MIC_MUTE_DISABLE},
+};
+
+static LIST_HEAD(smbios_device_list);
+
+int dell_smbios_error(int value)
+{
+ switch (value) {
+ case 0: /* Completed successfully */
+ return 0;
+ case -1: /* Completed with error */
+ return -EIO;
+ case -2: /* Function not supported */
+ return -ENXIO;
+ default: /* Unknown error */
+ return -EINVAL;
+ }
+}
+EXPORT_SYMBOL_GPL(dell_smbios_error);
+
+int dell_smbios_register_device(struct device *d, void *call_fn)
+{
+ struct smbios_device *priv;
+
+ priv = devm_kzalloc(d, sizeof(struct smbios_device), GFP_KERNEL);
+ if (!priv)
+ return -ENOMEM;
+ get_device(d);
+ priv->device = d;
+ priv->call_fn = call_fn;
+ mutex_lock(&smbios_mutex);
+ list_add_tail(&priv->list, &smbios_device_list);
+ mutex_unlock(&smbios_mutex);
+ dev_dbg(d, "Added device: %s\n", d->driver->name);
+ return 0;
+}
+EXPORT_SYMBOL_GPL(dell_smbios_register_device);
+
+void dell_smbios_unregister_device(struct device *d)
+{
+ struct smbios_device *priv;
+
+ mutex_lock(&smbios_mutex);
+ list_for_each_entry(priv, &smbios_device_list, list) {
+ if (priv->device == d) {
+ list_del(&priv->list);
+ put_device(d);
+ break;
+ }
+ }
+ mutex_unlock(&smbios_mutex);
+ dev_dbg(d, "Remove device: %s\n", d->driver->name);
+}
+EXPORT_SYMBOL_GPL(dell_smbios_unregister_device);
+
+int dell_smbios_call_filter(struct device *d,
+ struct calling_interface_buffer *buffer)
+{
+ u16 t = 0;
+ int i;
+
+ /* can't make calls over 30 */
+ if (buffer->cmd_class > 30) {
+ dev_dbg(d, "class too big: %u\n", buffer->cmd_class);
+ return -EINVAL;
+ }
+
+ /* supported calls on the particular system */
+ if (!(da_supported_commands & (1 << buffer->cmd_class))) {
+ dev_dbg(d, "invalid command, supported commands: 0x%8x\n",
+ da_supported_commands);
+ return -EINVAL;
+ }
+
+ /* match against call blacklist */
+ for (i = 0; i < ARRAY_SIZE(call_blacklist); i++) {
+ if (buffer->cmd_class != call_blacklist[i].cmd_class)
+ continue;
+ if (buffer->cmd_select != call_blacklist[i].cmd_select &&
+ call_blacklist[i].cmd_select != -1)
+ continue;
+ dev_dbg(d, "blacklisted command: %u/%u\n",
+ buffer->cmd_class, buffer->cmd_select);
+ return -EINVAL;
+ }
+
+ /* if a token call, find token ID */
+
+ if ((buffer->cmd_class == CLASS_TOKEN_READ ||
+ buffer->cmd_class == CLASS_TOKEN_WRITE) &&
+ buffer->cmd_select < 3) {
+ /* find the matching token ID */
+ for (i = 0; i < da_num_tokens; i++) {
+ if (da_tokens[i].location != buffer->input[0])
+ continue;
+ t = da_tokens[i].tokenID;
+ break;
+ }
+
+ /* token call; but token didn't exist */
+ if (!t) {
+ dev_dbg(d, "token at location %04x doesn't exist\n",
+ buffer->input[0]);
+ return -EINVAL;
+ }
+
+ /* match against token blacklist */
+ for (i = 0; i < ARRAY_SIZE(token_blacklist); i++) {
+ if (!token_blacklist[i].min || !token_blacklist[i].max)
+ continue;
+ if (t >= token_blacklist[i].min &&
+ t <= token_blacklist[i].max)
+ return -EINVAL;
+ }
+
+ /* match against token whitelist */
+ for (i = 0; i < ARRAY_SIZE(token_whitelist); i++) {
+ if (!token_whitelist[i].min || !token_whitelist[i].max)
+ continue;
+ if (t < token_whitelist[i].min ||
+ t > token_whitelist[i].max)
+ continue;
+ if (!token_whitelist[i].need_capability ||
+ capable(token_whitelist[i].need_capability)) {
+ dev_dbg(d, "whitelisted token: %x\n", t);
+ return 0;
+ }
+
+ }
+ }
+ /* match against call whitelist */
+ for (i = 0; i < ARRAY_SIZE(call_whitelist); i++) {
+ if (buffer->cmd_class != call_whitelist[i].cmd_class)
+ continue;
+ if (buffer->cmd_select != call_whitelist[i].cmd_select)
+ continue;
+ if (!call_whitelist[i].need_capability ||
+ capable(call_whitelist[i].need_capability)) {
+ dev_dbg(d, "whitelisted capable command: %u/%u\n",
+ buffer->cmd_class, buffer->cmd_select);
+ return 0;
+ }
+ dev_dbg(d, "missing capability %d for %u/%u\n",
+ call_whitelist[i].need_capability,
+ buffer->cmd_class, buffer->cmd_select);
+
+ }
+
+ /* not in a whitelist, only allow processes with capabilities */
+ if (capable(CAP_SYS_RAWIO)) {
+ dev_dbg(d, "Allowing %u/%u due to CAP_SYS_RAWIO\n",
+ buffer->cmd_class, buffer->cmd_select);
+ return 0;
+ }
+
+ return -EACCES;
+}
+EXPORT_SYMBOL_GPL(dell_smbios_call_filter);
+
+int dell_smbios_call(struct calling_interface_buffer *buffer)
+{
+ int (*call_fn)(struct calling_interface_buffer *) = NULL;
+ struct device *selected_dev = NULL;
+ struct smbios_device *priv;
+ int ret;
+
+ mutex_lock(&smbios_mutex);
+ list_for_each_entry(priv, &smbios_device_list, list) {
+ if (!selected_dev || priv->device->id >= selected_dev->id) {
+ dev_dbg(priv->device, "Trying device ID: %d\n",
+ priv->device->id);
+ call_fn = priv->call_fn;
+ selected_dev = priv->device;
+ }
+ }
+
+ if (!selected_dev) {
+ ret = -ENODEV;
+ pr_err("No dell-smbios drivers are loaded\n");
+ goto out_smbios_call;
+ }
+
+ ret = call_fn(buffer);
+
+out_smbios_call:
+ mutex_unlock(&smbios_mutex);
+ return ret;
+}
+EXPORT_SYMBOL_GPL(dell_smbios_call);
+
+struct calling_interface_token *dell_smbios_find_token(int tokenid)
+{
+ int i;
+
+ for (i = 0; i < da_num_tokens; i++) {
+ if (da_tokens[i].tokenID == tokenid)
+ return &da_tokens[i];
+ }
+
+ return NULL;
+}
+EXPORT_SYMBOL_GPL(dell_smbios_find_token);
+
+static BLOCKING_NOTIFIER_HEAD(dell_laptop_chain_head);
+
+int dell_laptop_register_notifier(struct notifier_block *nb)
+{
+ return blocking_notifier_chain_register(&dell_laptop_chain_head, nb);
+}
+EXPORT_SYMBOL_GPL(dell_laptop_register_notifier);
+
+int dell_laptop_unregister_notifier(struct notifier_block *nb)
+{
+ return blocking_notifier_chain_unregister(&dell_laptop_chain_head, nb);
+}
+EXPORT_SYMBOL_GPL(dell_laptop_unregister_notifier);
+
+void dell_laptop_call_notifier(unsigned long action, void *data)
+{
+ blocking_notifier_call_chain(&dell_laptop_chain_head, action, data);
+}
+EXPORT_SYMBOL_GPL(dell_laptop_call_notifier);
+
+static void __init parse_da_table(const struct dmi_header *dm)
+{
+ /* Final token is a terminator, so we don't want to copy it */
+ int tokens = (dm->length-11)/sizeof(struct calling_interface_token)-1;
+ struct calling_interface_token *new_da_tokens;
+ struct calling_interface_structure *table =
+ container_of(dm, struct calling_interface_structure, header);
+
+ /*
+ * 4 bytes of table header, plus 7 bytes of Dell header
+ * plus at least 6 bytes of entry
+ */
+
+ if (dm->length < 17)
+ return;
+
+ da_supported_commands = table->supportedCmds;
+
+ new_da_tokens = krealloc(da_tokens, (da_num_tokens + tokens) *
+ sizeof(struct calling_interface_token),
+ GFP_KERNEL);
+
+ if (!new_da_tokens)
+ return;
+ da_tokens = new_da_tokens;
+
+ memcpy(da_tokens+da_num_tokens, table->tokens,
+ sizeof(struct calling_interface_token) * tokens);
+
+ da_num_tokens += tokens;
+}
+
+static void zero_duplicates(struct device *dev)
+{
+ int i, j;
+
+ for (i = 0; i < da_num_tokens; i++) {
+ if (da_tokens[i].tokenID == 0)
+ continue;
+ for (j = i+1; j < da_num_tokens; j++) {
+ if (da_tokens[j].tokenID == 0)
+ continue;
+ if (da_tokens[i].tokenID == da_tokens[j].tokenID) {
+ dev_dbg(dev, "Zeroing dup token ID %x(%x/%x)\n",
+ da_tokens[j].tokenID,
+ da_tokens[j].location,
+ da_tokens[j].value);
+ da_tokens[j].tokenID = 0;
+ }
+ }
+ }
+}
+
+static void __init find_tokens(const struct dmi_header *dm, void *dummy)
+{
+ switch (dm->type) {
+ case 0xd4: /* Indexed IO */
+ case 0xd5: /* Protected Area Type 1 */
+ case 0xd6: /* Protected Area Type 2 */
+ break;
+ case 0xda: /* Calling interface */
+ parse_da_table(dm);
+ break;
+ }
+}
+
+static int match_attribute(struct device *dev,
+ struct device_attribute *attr)
+{
+ int i;
+
+ for (i = 0; i < da_num_tokens * 2; i++) {
+ if (!token_attrs[i])
+ continue;
+ if (strcmp(token_attrs[i]->name, attr->attr.name) == 0)
+ return i/2;
+ }
+ dev_dbg(dev, "couldn't match: %s\n", attr->attr.name);
+ return -EINVAL;
+}
+
+static ssize_t location_show(struct device *dev,
+ struct device_attribute *attr, char *buf)
+{
+ int i;
+
+ if (!capable(CAP_SYS_ADMIN))
+ return -EPERM;
+
+ i = match_attribute(dev, attr);
+ if (i > 0)
+ return scnprintf(buf, PAGE_SIZE, "%08x", da_tokens[i].location);
+ return 0;
+}
+
+static ssize_t value_show(struct device *dev,
+ struct device_attribute *attr, char *buf)
+{
+ int i;
+
+ if (!capable(CAP_SYS_ADMIN))
+ return -EPERM;
+
+ i = match_attribute(dev, attr);
+ if (i > 0)
+ return scnprintf(buf, PAGE_SIZE, "%08x", da_tokens[i].value);
+ return 0;
+}
+
+static struct attribute_group smbios_attribute_group = {
+ .name = "tokens"
+};
+
+static struct platform_driver platform_driver = {
+ .driver = {
+ .name = "dell-smbios",
+ },
+};
+
+static int build_tokens_sysfs(struct platform_device *dev)
+{
+ char *location_name;
+ char *value_name;
+ size_t size;
+ int ret;
+ int i, j;
+
+ /* (number of tokens + 1 for null terminated */
+ size = sizeof(struct device_attribute) * (da_num_tokens + 1);
+ token_location_attrs = kzalloc(size, GFP_KERNEL);
+ if (!token_location_attrs)
+ return -ENOMEM;
+ token_value_attrs = kzalloc(size, GFP_KERNEL);
+ if (!token_value_attrs)
+ goto out_allocate_value;
+
+ /* need to store both location and value + terminator*/
+ size = sizeof(struct attribute *) * ((2 * da_num_tokens) + 1);
+ token_attrs = kzalloc(size, GFP_KERNEL);
+ if (!token_attrs)
+ goto out_allocate_attrs;
+
+ for (i = 0, j = 0; i < da_num_tokens; i++) {
+ /* skip empty */
+ if (da_tokens[i].tokenID == 0)
+ continue;
+ /* add location */
+ location_name = kasprintf(GFP_KERNEL, "%04x_location",
+ da_tokens[i].tokenID);
+ if (location_name == NULL)
+ goto out_unwind_strings;
+ sysfs_attr_init(&token_location_attrs[i].attr);
+ token_location_attrs[i].attr.name = location_name;
+ token_location_attrs[i].attr.mode = 0444;
+ token_location_attrs[i].show = location_show;
+ token_attrs[j++] = &token_location_attrs[i].attr;
+
+ /* add value */
+ value_name = kasprintf(GFP_KERNEL, "%04x_value",
+ da_tokens[i].tokenID);
+ if (value_name == NULL)
+ goto loop_fail_create_value;
+ sysfs_attr_init(&token_value_attrs[i].attr);
+ token_value_attrs[i].attr.name = value_name;
+ token_value_attrs[i].attr.mode = 0444;
+ token_value_attrs[i].show = value_show;
+ token_attrs[j++] = &token_value_attrs[i].attr;
+ continue;
+
+loop_fail_create_value:
+ kfree(value_name);
+ goto out_unwind_strings;
+ }
+ smbios_attribute_group.attrs = token_attrs;
+
+ ret = sysfs_create_group(&dev->dev.kobj, &smbios_attribute_group);
+ if (ret)
+ goto out_unwind_strings;
+ return 0;
+
+out_unwind_strings:
+ for (i = i-1; i > 0; i--) {
+ kfree(token_location_attrs[i].attr.name);
+ kfree(token_value_attrs[i].attr.name);
+ }
+ kfree(token_attrs);
+out_allocate_attrs:
+ kfree(token_value_attrs);
+out_allocate_value:
+ kfree(token_location_attrs);
+
+ return -ENOMEM;
+}
+
+static void free_group(struct platform_device *pdev)
+{
+ int i;
+
+ sysfs_remove_group(&pdev->dev.kobj,
+ &smbios_attribute_group);
+ for (i = 0; i < da_num_tokens; i++) {
+ kfree(token_location_attrs[i].attr.name);
+ kfree(token_value_attrs[i].attr.name);
+ }
+ kfree(token_attrs);
+ kfree(token_value_attrs);
+ kfree(token_location_attrs);
+}
+
+static int __init dell_smbios_init(void)
+{
+ const struct dmi_device *valid;
+ int ret, wmi, smm;
+
+ valid = dmi_find_device(DMI_DEV_TYPE_OEM_STRING, "Dell System", NULL);
+ if (!valid) {
+ pr_err("Unable to run on non-Dell system\n");
+ return -ENODEV;
+ }
+
+ dmi_walk(find_tokens, NULL);
+
+ if (!da_tokens) {
+ pr_info("Unable to find dmi tokens\n");
+ return -ENODEV;
+ }
+
+ ret = platform_driver_register(&platform_driver);
+ if (ret)
+ goto fail_platform_driver;
+
+ platform_device = platform_device_alloc("dell-smbios", 0);
+ if (!platform_device) {
+ ret = -ENOMEM;
+ goto fail_platform_device_alloc;
+ }
+ ret = platform_device_add(platform_device);
+ if (ret)
+ goto fail_platform_device_add;
+
+ /* duplicate tokens will cause problems building sysfs files */
+ zero_duplicates(&platform_device->dev);
+
+ ret = build_tokens_sysfs(platform_device);
+ if (ret)
+ goto fail_create_group;
+
+ /* register backends */
+ wmi = init_dell_smbios_wmi();
+ if (wmi)
+ pr_debug("Failed to initialize WMI backend: %d\n", wmi);
+ smm = init_dell_smbios_smm();
+ if (smm)
+ pr_debug("Failed to initialize SMM backend: %d\n", smm);
+ if (wmi && smm) {
+ pr_err("No SMBIOS backends available (wmi: %d, smm: %d)\n",
+ wmi, smm);
+ goto fail_sysfs;
+ }
+
+ return 0;
+
+fail_sysfs:
+ free_group(platform_device);
+
+fail_create_group:
+ platform_device_del(platform_device);
+
+fail_platform_device_add:
+ platform_device_put(platform_device);
+
+fail_platform_device_alloc:
+ platform_driver_unregister(&platform_driver);
+
+fail_platform_driver:
+ kfree(da_tokens);
+ return ret;
+}
+
+static void __exit dell_smbios_exit(void)
+{
+ exit_dell_smbios_wmi();
+ exit_dell_smbios_smm();
+ mutex_lock(&smbios_mutex);
+ if (platform_device) {
+ free_group(platform_device);
+ platform_device_unregister(platform_device);
+ platform_driver_unregister(&platform_driver);
+ }
+ kfree(da_tokens);
+ mutex_unlock(&smbios_mutex);
+}
+
+subsys_initcall(dell_smbios_init);
+module_exit(dell_smbios_exit);
+
+MODULE_AUTHOR("Matthew Garrett <mjg@redhat.com>");
+MODULE_AUTHOR("Gabriele Mazzotta <gabriele.mzt@gmail.com>");
+MODULE_AUTHOR("Pali Rohár <pali.rohar@gmail.com>");
+MODULE_AUTHOR("Mario Limonciello <mario.limonciello@dell.com>");
+MODULE_DESCRIPTION("Common functions for kernel modules using Dell SMBIOS");
+MODULE_LICENSE("GPL");
generated by cgit v1.2.3 (git 2.39.1) at 2024-12-18 21:54:10 +0000