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path: root/drivers/net/usb/cdc_mbim.c
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Diffstat (limited to 'drivers/net/usb/cdc_mbim.c')
-rw-r--r--drivers/net/usb/cdc_mbim.c625
1 files changed, 625 insertions, 0 deletions
diff --git a/drivers/net/usb/cdc_mbim.c b/drivers/net/usb/cdc_mbim.c
new file mode 100644
index 00000000000..5ee7a1dbc02
--- /dev/null
+++ b/drivers/net/usb/cdc_mbim.c
@@ -0,0 +1,625 @@
+/*
+ * Copyright (c) 2012 Smith Micro Software, Inc.
+ * Copyright (c) 2012 Bjørn Mork <bjorn@mork.no>
+ *
+ * This driver is based on and reuse most of cdc_ncm, which is
+ * Copyright (C) ST-Ericsson 2010-2012
+ *
+ * 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.
+ */
+
+#include <linux/module.h>
+#include <linux/netdevice.h>
+#include <linux/ethtool.h>
+#include <linux/if_vlan.h>
+#include <linux/ip.h>
+#include <linux/mii.h>
+#include <linux/usb.h>
+#include <linux/usb/cdc.h>
+#include <linux/usb/usbnet.h>
+#include <linux/usb/cdc-wdm.h>
+#include <linux/usb/cdc_ncm.h>
+#include <net/ipv6.h>
+#include <net/addrconf.h>
+
+/* alternative VLAN for IP session 0 if not untagged */
+#define MBIM_IPS0_VID 4094
+
+/* driver specific data - must match cdc_ncm usage */
+struct cdc_mbim_state {
+ struct cdc_ncm_ctx *ctx;
+ atomic_t pmcount;
+ struct usb_driver *subdriver;
+ unsigned long _unused;
+ unsigned long flags;
+};
+
+/* flags for the cdc_mbim_state.flags field */
+enum cdc_mbim_flags {
+ FLAG_IPS0_VLAN = 1 << 0, /* IP session 0 is tagged */
+};
+
+/* using a counter to merge subdriver requests with our own into a combined state */
+static int cdc_mbim_manage_power(struct usbnet *dev, int on)
+{
+ struct cdc_mbim_state *info = (void *)&dev->data;
+ int rv = 0;
+
+ dev_dbg(&dev->intf->dev, "%s() pmcount=%d, on=%d\n", __func__, atomic_read(&info->pmcount), on);
+
+ if ((on && atomic_add_return(1, &info->pmcount) == 1) || (!on && atomic_dec_and_test(&info->pmcount))) {
+ /* need autopm_get/put here to ensure the usbcore sees the new value */
+ rv = usb_autopm_get_interface(dev->intf);
+ dev->intf->needs_remote_wakeup = on;
+ if (!rv)
+ usb_autopm_put_interface(dev->intf);
+ }
+ return 0;
+}
+
+static int cdc_mbim_wdm_manage_power(struct usb_interface *intf, int status)
+{
+ struct usbnet *dev = usb_get_intfdata(intf);
+
+ /* can be called while disconnecting */
+ if (!dev)
+ return 0;
+
+ return cdc_mbim_manage_power(dev, status);
+}
+
+static int cdc_mbim_rx_add_vid(struct net_device *netdev, __be16 proto, u16 vid)
+{
+ struct usbnet *dev = netdev_priv(netdev);
+ struct cdc_mbim_state *info = (void *)&dev->data;
+
+ /* creation of this VLAN is a request to tag IP session 0 */
+ if (vid == MBIM_IPS0_VID)
+ info->flags |= FLAG_IPS0_VLAN;
+ else
+ if (vid >= 512) /* we don't map these to MBIM session */
+ return -EINVAL;
+ return 0;
+}
+
+static int cdc_mbim_rx_kill_vid(struct net_device *netdev, __be16 proto, u16 vid)
+{
+ struct usbnet *dev = netdev_priv(netdev);
+ struct cdc_mbim_state *info = (void *)&dev->data;
+
+ /* this is a request for an untagged IP session 0 */
+ if (vid == MBIM_IPS0_VID)
+ info->flags &= ~FLAG_IPS0_VLAN;
+ return 0;
+}
+
+static const struct net_device_ops cdc_mbim_netdev_ops = {
+ .ndo_open = usbnet_open,
+ .ndo_stop = usbnet_stop,
+ .ndo_start_xmit = usbnet_start_xmit,
+ .ndo_tx_timeout = usbnet_tx_timeout,
+ .ndo_change_mtu = usbnet_change_mtu,
+ .ndo_set_mac_address = eth_mac_addr,
+ .ndo_validate_addr = eth_validate_addr,
+ .ndo_vlan_rx_add_vid = cdc_mbim_rx_add_vid,
+ .ndo_vlan_rx_kill_vid = cdc_mbim_rx_kill_vid,
+};
+
+/* Change the control interface altsetting and update the .driver_info
+ * pointer if the matching entry after changing class codes points to
+ * a different struct
+ */
+static int cdc_mbim_set_ctrlalt(struct usbnet *dev, struct usb_interface *intf, u8 alt)
+{
+ struct usb_driver *driver = to_usb_driver(intf->dev.driver);
+ const struct usb_device_id *id;
+ struct driver_info *info;
+ int ret;
+
+ ret = usb_set_interface(dev->udev,
+ intf->cur_altsetting->desc.bInterfaceNumber,
+ alt);
+ if (ret)
+ return ret;
+
+ id = usb_match_id(intf, driver->id_table);
+ if (!id)
+ return -ENODEV;
+
+ info = (struct driver_info *)id->driver_info;
+ if (info != dev->driver_info) {
+ dev_dbg(&intf->dev, "driver_info updated to '%s'\n",
+ info->description);
+ dev->driver_info = info;
+ }
+ return 0;
+}
+
+static int cdc_mbim_bind(struct usbnet *dev, struct usb_interface *intf)
+{
+ struct cdc_ncm_ctx *ctx;
+ struct usb_driver *subdriver = ERR_PTR(-ENODEV);
+ int ret = -ENODEV;
+ u8 data_altsetting = 1;
+ struct cdc_mbim_state *info = (void *)&dev->data;
+
+ /* should we change control altsetting on a NCM/MBIM function? */
+ if (cdc_ncm_select_altsetting(intf) == CDC_NCM_COMM_ALTSETTING_MBIM) {
+ data_altsetting = CDC_NCM_DATA_ALTSETTING_MBIM;
+ ret = cdc_mbim_set_ctrlalt(dev, intf, CDC_NCM_COMM_ALTSETTING_MBIM);
+ if (ret)
+ goto err;
+ ret = -ENODEV;
+ }
+
+ /* we will hit this for NCM/MBIM functions if prefer_mbim is false */
+ if (!cdc_ncm_comm_intf_is_mbim(intf->cur_altsetting))
+ goto err;
+
+ ret = cdc_ncm_bind_common(dev, intf, data_altsetting);
+ if (ret)
+ goto err;
+
+ ctx = info->ctx;
+
+ /* The MBIM descriptor and the status endpoint are required */
+ if (ctx->mbim_desc && dev->status)
+ subdriver = usb_cdc_wdm_register(ctx->control,
+ &dev->status->desc,
+ le16_to_cpu(ctx->mbim_desc->wMaxControlMessage),
+ cdc_mbim_wdm_manage_power);
+ if (IS_ERR(subdriver)) {
+ ret = PTR_ERR(subdriver);
+ cdc_ncm_unbind(dev, intf);
+ goto err;
+ }
+
+ /* can't let usbnet use the interrupt endpoint */
+ dev->status = NULL;
+ info->subdriver = subdriver;
+
+ /* MBIM cannot do ARP */
+ dev->net->flags |= IFF_NOARP;
+
+ /* no need to put the VLAN tci in the packet headers */
+ dev->net->features |= NETIF_F_HW_VLAN_CTAG_TX | NETIF_F_HW_VLAN_CTAG_FILTER;
+
+ /* monitor VLAN additions and removals */
+ dev->net->netdev_ops = &cdc_mbim_netdev_ops;
+err:
+ return ret;
+}
+
+static void cdc_mbim_unbind(struct usbnet *dev, struct usb_interface *intf)
+{
+ struct cdc_mbim_state *info = (void *)&dev->data;
+ struct cdc_ncm_ctx *ctx = info->ctx;
+
+ /* disconnect subdriver from control interface */
+ if (info->subdriver && info->subdriver->disconnect)
+ info->subdriver->disconnect(ctx->control);
+ info->subdriver = NULL;
+
+ /* let NCM unbind clean up both control and data interface */
+ cdc_ncm_unbind(dev, intf);
+}
+
+/* verify that the ethernet protocol is IPv4 or IPv6 */
+static bool is_ip_proto(__be16 proto)
+{
+ switch (proto) {
+ case htons(ETH_P_IP):
+ case htons(ETH_P_IPV6):
+ return true;
+ }
+ return false;
+}
+
+static struct sk_buff *cdc_mbim_tx_fixup(struct usbnet *dev, struct sk_buff *skb, gfp_t flags)
+{
+ struct sk_buff *skb_out;
+ struct cdc_mbim_state *info = (void *)&dev->data;
+ struct cdc_ncm_ctx *ctx = info->ctx;
+ __le32 sign = cpu_to_le32(USB_CDC_MBIM_NDP16_IPS_SIGN);
+ u16 tci = 0;
+ bool is_ip;
+ u8 *c;
+
+ if (!ctx)
+ goto error;
+
+ if (skb) {
+ if (skb->len <= ETH_HLEN)
+ goto error;
+
+ /* Some applications using e.g. packet sockets will
+ * bypass the VLAN acceleration and create tagged
+ * ethernet frames directly. We primarily look for
+ * the accelerated out-of-band tag, but fall back if
+ * required
+ */
+ skb_reset_mac_header(skb);
+ if (vlan_get_tag(skb, &tci) < 0 && skb->len > VLAN_ETH_HLEN &&
+ __vlan_get_tag(skb, &tci) == 0) {
+ is_ip = is_ip_proto(vlan_eth_hdr(skb)->h_vlan_encapsulated_proto);
+ skb_pull(skb, VLAN_ETH_HLEN);
+ } else {
+ is_ip = is_ip_proto(eth_hdr(skb)->h_proto);
+ skb_pull(skb, ETH_HLEN);
+ }
+
+ /* Is IP session <0> tagged too? */
+ if (info->flags & FLAG_IPS0_VLAN) {
+ /* drop all untagged packets */
+ if (!tci)
+ goto error;
+ /* map MBIM_IPS0_VID to IPS<0> */
+ if (tci == MBIM_IPS0_VID)
+ tci = 0;
+ }
+
+ /* mapping VLANs to MBIM sessions:
+ * no tag => IPS session <0> if !FLAG_IPS0_VLAN
+ * 1 - 255 => IPS session <vlanid>
+ * 256 - 511 => DSS session <vlanid - 256>
+ * 512 - 4093 => unsupported, drop
+ * 4094 => IPS session <0> if FLAG_IPS0_VLAN
+ */
+
+ switch (tci & 0x0f00) {
+ case 0x0000: /* VLAN ID 0 - 255 */
+ if (!is_ip)
+ goto error;
+ c = (u8 *)&sign;
+ c[3] = tci;
+ break;
+ case 0x0100: /* VLAN ID 256 - 511 */
+ if (is_ip)
+ goto error;
+ sign = cpu_to_le32(USB_CDC_MBIM_NDP16_DSS_SIGN);
+ c = (u8 *)&sign;
+ c[3] = tci;
+ break;
+ default:
+ netif_err(dev, tx_err, dev->net,
+ "unsupported tci=0x%04x\n", tci);
+ goto error;
+ }
+ }
+
+ spin_lock_bh(&ctx->mtx);
+ skb_out = cdc_ncm_fill_tx_frame(dev, skb, sign);
+ spin_unlock_bh(&ctx->mtx);
+ return skb_out;
+
+error:
+ if (skb)
+ dev_kfree_skb_any(skb);
+
+ return NULL;
+}
+
+/* Some devices are known to send Neigbor Solicitation messages and
+ * require Neigbor Advertisement replies. The IPv6 core will not
+ * respond since IFF_NOARP is set, so we must handle them ourselves.
+ */
+static void do_neigh_solicit(struct usbnet *dev, u8 *buf, u16 tci)
+{
+ struct ipv6hdr *iph = (void *)buf;
+ struct nd_msg *msg = (void *)(iph + 1);
+ struct net_device *netdev;
+ struct inet6_dev *in6_dev;
+ bool is_router;
+
+ /* we'll only respond to requests from unicast addresses to
+ * our solicited node addresses.
+ */
+ if (!ipv6_addr_is_solict_mult(&iph->daddr) ||
+ !(ipv6_addr_type(&iph->saddr) & IPV6_ADDR_UNICAST))
+ return;
+
+ /* need to send the NA on the VLAN dev, if any */
+ rcu_read_lock();
+ if (tci) {
+ netdev = __vlan_find_dev_deep_rcu(dev->net, htons(ETH_P_8021Q),
+ tci);
+ if (!netdev) {
+ rcu_read_unlock();
+ return;
+ }
+ } else {
+ netdev = dev->net;
+ }
+ dev_hold(netdev);
+ rcu_read_unlock();
+
+ in6_dev = in6_dev_get(netdev);
+ if (!in6_dev)
+ goto out;
+ is_router = !!in6_dev->cnf.forwarding;
+ in6_dev_put(in6_dev);
+
+ /* ipv6_stub != NULL if in6_dev_get returned an inet6_dev */
+ ipv6_stub->ndisc_send_na(netdev, NULL, &iph->saddr, &msg->target,
+ is_router /* router */,
+ true /* solicited */,
+ false /* override */,
+ true /* inc_opt */);
+out:
+ dev_put(netdev);
+}
+
+static bool is_neigh_solicit(u8 *buf, size_t len)
+{
+ struct ipv6hdr *iph = (void *)buf;
+ struct nd_msg *msg = (void *)(iph + 1);
+
+ return (len >= sizeof(struct ipv6hdr) + sizeof(struct nd_msg) &&
+ iph->nexthdr == IPPROTO_ICMPV6 &&
+ msg->icmph.icmp6_code == 0 &&
+ msg->icmph.icmp6_type == NDISC_NEIGHBOUR_SOLICITATION);
+}
+
+
+static struct sk_buff *cdc_mbim_process_dgram(struct usbnet *dev, u8 *buf, size_t len, u16 tci)
+{
+ __be16 proto = htons(ETH_P_802_3);
+ struct sk_buff *skb = NULL;
+
+ if (tci < 256 || tci == MBIM_IPS0_VID) { /* IPS session? */
+ if (len < sizeof(struct iphdr))
+ goto err;
+
+ switch (*buf & 0xf0) {
+ case 0x40:
+ proto = htons(ETH_P_IP);
+ break;
+ case 0x60:
+ if (is_neigh_solicit(buf, len))
+ do_neigh_solicit(dev, buf, tci);
+ proto = htons(ETH_P_IPV6);
+ break;
+ default:
+ goto err;
+ }
+ }
+
+ skb = netdev_alloc_skb_ip_align(dev->net, len + ETH_HLEN);
+ if (!skb)
+ goto err;
+
+ /* add an ethernet header */
+ skb_put(skb, ETH_HLEN);
+ skb_reset_mac_header(skb);
+ eth_hdr(skb)->h_proto = proto;
+ memset(eth_hdr(skb)->h_source, 0, ETH_ALEN);
+ memcpy(eth_hdr(skb)->h_dest, dev->net->dev_addr, ETH_ALEN);
+
+ /* add datagram */
+ memcpy(skb_put(skb, len), buf, len);
+
+ /* map MBIM session to VLAN */
+ if (tci)
+ vlan_put_tag(skb, htons(ETH_P_8021Q), tci);
+err:
+ return skb;
+}
+
+static int cdc_mbim_rx_fixup(struct usbnet *dev, struct sk_buff *skb_in)
+{
+ struct sk_buff *skb;
+ struct cdc_mbim_state *info = (void *)&dev->data;
+ struct cdc_ncm_ctx *ctx = info->ctx;
+ int len;
+ int nframes;
+ int x;
+ int offset;
+ struct usb_cdc_ncm_ndp16 *ndp16;
+ struct usb_cdc_ncm_dpe16 *dpe16;
+ int ndpoffset;
+ int loopcount = 50; /* arbitrary max preventing infinite loop */
+ u32 payload = 0;
+ u8 *c;
+ u16 tci;
+
+ ndpoffset = cdc_ncm_rx_verify_nth16(ctx, skb_in);
+ if (ndpoffset < 0)
+ goto error;
+
+next_ndp:
+ nframes = cdc_ncm_rx_verify_ndp16(skb_in, ndpoffset);
+ if (nframes < 0)
+ goto error;
+
+ ndp16 = (struct usb_cdc_ncm_ndp16 *)(skb_in->data + ndpoffset);
+
+ switch (ndp16->dwSignature & cpu_to_le32(0x00ffffff)) {
+ case cpu_to_le32(USB_CDC_MBIM_NDP16_IPS_SIGN):
+ c = (u8 *)&ndp16->dwSignature;
+ tci = c[3];
+ /* tag IPS<0> packets too if MBIM_IPS0_VID exists */
+ if (!tci && info->flags & FLAG_IPS0_VLAN)
+ tci = MBIM_IPS0_VID;
+ break;
+ case cpu_to_le32(USB_CDC_MBIM_NDP16_DSS_SIGN):
+ c = (u8 *)&ndp16->dwSignature;
+ tci = c[3] + 256;
+ break;
+ default:
+ netif_dbg(dev, rx_err, dev->net,
+ "unsupported NDP signature <0x%08x>\n",
+ le32_to_cpu(ndp16->dwSignature));
+ goto err_ndp;
+
+ }
+
+ dpe16 = ndp16->dpe16;
+ for (x = 0; x < nframes; x++, dpe16++) {
+ offset = le16_to_cpu(dpe16->wDatagramIndex);
+ len = le16_to_cpu(dpe16->wDatagramLength);
+
+ /*
+ * CDC NCM ch. 3.7
+ * All entries after first NULL entry are to be ignored
+ */
+ if ((offset == 0) || (len == 0)) {
+ if (!x)
+ goto err_ndp; /* empty NTB */
+ break;
+ }
+
+ /* sanity checking */
+ if (((offset + len) > skb_in->len) || (len > ctx->rx_max)) {
+ netif_dbg(dev, rx_err, dev->net,
+ "invalid frame detected (ignored) offset[%u]=%u, length=%u, skb=%p\n",
+ x, offset, len, skb_in);
+ if (!x)
+ goto err_ndp;
+ break;
+ } else {
+ skb = cdc_mbim_process_dgram(dev, skb_in->data + offset, len, tci);
+ if (!skb)
+ goto error;
+ usbnet_skb_return(dev, skb);
+ payload += len; /* count payload bytes in this NTB */
+ }
+ }
+err_ndp:
+ /* are there more NDPs to process? */
+ ndpoffset = le16_to_cpu(ndp16->wNextNdpIndex);
+ if (ndpoffset && loopcount--)
+ goto next_ndp;
+
+ /* update stats */
+ ctx->rx_overhead += skb_in->len - payload;
+ ctx->rx_ntbs++;
+
+ return 1;
+error:
+ return 0;
+}
+
+static int cdc_mbim_suspend(struct usb_interface *intf, pm_message_t message)
+{
+ int ret = -ENODEV;
+ struct usbnet *dev = usb_get_intfdata(intf);
+ struct cdc_mbim_state *info = (void *)&dev->data;
+ struct cdc_ncm_ctx *ctx = info->ctx;
+
+ if (!ctx)
+ goto error;
+
+ /*
+ * Both usbnet_suspend() and subdriver->suspend() MUST return 0
+ * in system sleep context, otherwise, the resume callback has
+ * to recover device from previous suspend failure.
+ */
+ ret = usbnet_suspend(intf, message);
+ if (ret < 0)
+ goto error;
+
+ if (intf == ctx->control && info->subdriver && info->subdriver->suspend)
+ ret = info->subdriver->suspend(intf, message);
+ if (ret < 0)
+ usbnet_resume(intf);
+
+error:
+ return ret;
+}
+
+static int cdc_mbim_resume(struct usb_interface *intf)
+{
+ int ret = 0;
+ struct usbnet *dev = usb_get_intfdata(intf);
+ struct cdc_mbim_state *info = (void *)&dev->data;
+ struct cdc_ncm_ctx *ctx = info->ctx;
+ bool callsub = (intf == ctx->control && info->subdriver && info->subdriver->resume);
+
+ if (callsub)
+ ret = info->subdriver->resume(intf);
+ if (ret < 0)
+ goto err;
+ ret = usbnet_resume(intf);
+ if (ret < 0 && callsub)
+ info->subdriver->suspend(intf, PMSG_SUSPEND);
+err:
+ return ret;
+}
+
+static const struct driver_info cdc_mbim_info = {
+ .description = "CDC MBIM",
+ .flags = FLAG_NO_SETINT | FLAG_MULTI_PACKET | FLAG_WWAN,
+ .bind = cdc_mbim_bind,
+ .unbind = cdc_mbim_unbind,
+ .manage_power = cdc_mbim_manage_power,
+ .rx_fixup = cdc_mbim_rx_fixup,
+ .tx_fixup = cdc_mbim_tx_fixup,
+};
+
+/* MBIM and NCM devices should not need a ZLP after NTBs with
+ * dwNtbOutMaxSize length. Nevertheless, a number of devices from
+ * different vendor IDs will fail unless we send ZLPs, forcing us
+ * to make this the default.
+ *
+ * This default may cause a performance penalty for spec conforming
+ * devices wanting to take advantage of optimizations possible without
+ * ZLPs. A whitelist is added in an attempt to avoid this for devices
+ * known to conform to the MBIM specification.
+ *
+ * All known devices supporting NCM compatibility mode are also
+ * conforming to the NCM and MBIM specifications. For this reason, the
+ * NCM subclass entry is also in the ZLP whitelist.
+ */
+static const struct driver_info cdc_mbim_info_zlp = {
+ .description = "CDC MBIM",
+ .flags = FLAG_NO_SETINT | FLAG_MULTI_PACKET | FLAG_WWAN | FLAG_SEND_ZLP,
+ .bind = cdc_mbim_bind,
+ .unbind = cdc_mbim_unbind,
+ .manage_power = cdc_mbim_manage_power,
+ .rx_fixup = cdc_mbim_rx_fixup,
+ .tx_fixup = cdc_mbim_tx_fixup,
+};
+
+static const struct usb_device_id mbim_devs[] = {
+ /* This duplicate NCM entry is intentional. MBIM devices can
+ * be disguised as NCM by default, and this is necessary to
+ * allow us to bind the correct driver_info to such devices.
+ *
+ * bind() will sort out this for us, selecting the correct
+ * entry and reject the other
+ */
+ { USB_INTERFACE_INFO(USB_CLASS_COMM, USB_CDC_SUBCLASS_NCM, USB_CDC_PROTO_NONE),
+ .driver_info = (unsigned long)&cdc_mbim_info,
+ },
+ /* ZLP conformance whitelist: All Ericsson MBIM devices */
+ { USB_VENDOR_AND_INTERFACE_INFO(0x0bdb, USB_CLASS_COMM, USB_CDC_SUBCLASS_MBIM, USB_CDC_PROTO_NONE),
+ .driver_info = (unsigned long)&cdc_mbim_info,
+ },
+ /* default entry */
+ { USB_INTERFACE_INFO(USB_CLASS_COMM, USB_CDC_SUBCLASS_MBIM, USB_CDC_PROTO_NONE),
+ .driver_info = (unsigned long)&cdc_mbim_info_zlp,
+ },
+ {
+ },
+};
+MODULE_DEVICE_TABLE(usb, mbim_devs);
+
+static struct usb_driver cdc_mbim_driver = {
+ .name = "cdc_mbim",
+ .id_table = mbim_devs,
+ .probe = usbnet_probe,
+ .disconnect = usbnet_disconnect,
+ .suspend = cdc_mbim_suspend,
+ .resume = cdc_mbim_resume,
+ .reset_resume = cdc_mbim_resume,
+ .supports_autosuspend = 1,
+ .disable_hub_initiated_lpm = 1,
+};
+module_usb_driver(cdc_mbim_driver);
+
+MODULE_AUTHOR("Greg Suarez <gsuarez@smithmicro.com>");
+MODULE_AUTHOR("Bjørn Mork <bjorn@mork.no>");
+MODULE_DESCRIPTION("USB CDC MBIM host driver");
+MODULE_LICENSE("GPL");
generated by cgit v1.2.3-70-g09d2 (git 2.46.0) at 2025-11-04 01:48:37 +0000