From 52409fae3e4b8d16b68b61902fc09075cd97b75d Mon Sep 17 00:00:00 2001 From: Dominik Sliwa Date: Sun, 2 Jul 2017 16:41:37 +0200 Subject: Backports generated from 4.11 kernel Initial commit. Signed-off-by: Dominik Sliwa --- drivers/net/usb/rndis_host.c | 653 +++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 653 insertions(+) create mode 100644 drivers/net/usb/rndis_host.c (limited to 'drivers/net/usb/rndis_host.c') diff --git a/drivers/net/usb/rndis_host.c b/drivers/net/usb/rndis_host.c new file mode 100644 index 0000000..c5b2113 --- /dev/null +++ b/drivers/net/usb/rndis_host.c @@ -0,0 +1,653 @@ +/* + * Host Side support for RNDIS Networking Links + * Copyright (C) 2005 by David Brownell + * + * This program is free software; you can redistribute it and/or modify + * it under the terms of the GNU General Public License as published by + * the Free Software Foundation; either version 2 of the License, or + * (at your option) any later version. + * + * This program is distributed in the hope that it will be useful, + * but WITHOUT ANY WARRANTY; without even the implied warranty of + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the + * GNU General Public License for more details. + * + * You should have received a copy of the GNU General Public License + * along with this program; if not, see . + */ +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include + + +/* + * RNDIS is NDIS remoted over USB. It's a MSFT variant of CDC ACM ... of + * course ACM was intended for modems, not Ethernet links! USB's standard + * for Ethernet links is "CDC Ethernet", which is significantly simpler. + * + * NOTE that Microsoft's "RNDIS 1.0" specification is incomplete. Issues + * include: + * - Power management in particular relies on information that's scattered + * through other documentation, and which is incomplete or incorrect even + * there. + * - There are various undocumented protocol requirements, such as the + * need to send unused garbage in control-OUT messages. + * - In some cases, MS-Windows will emit undocumented requests; this + * matters more to peripheral implementations than host ones. + * + * Moreover there's a no-open-specs variant of RNDIS called "ActiveSync". + * + * For these reasons and others, ** USE OF RNDIS IS STRONGLY DISCOURAGED ** in + * favor of such non-proprietary alternatives as CDC Ethernet or the newer (and + * currently rare) "Ethernet Emulation Model" (EEM). + */ + +/* + * RNDIS notifications from device: command completion; "reverse" + * keepalives; etc + */ +void rndis_status(struct usbnet *dev, struct urb *urb) +{ + netdev_dbg(dev->net, "rndis status urb, len %d stat %d\n", + urb->actual_length, urb->status); + // FIXME for keepalives, respond immediately (asynchronously) + // if not an RNDIS status, do like cdc_status(dev,urb) does +} +EXPORT_SYMBOL_GPL(rndis_status); + +/* + * RNDIS indicate messages. + */ +static void rndis_msg_indicate(struct usbnet *dev, struct rndis_indicate *msg, + int buflen) +{ + struct cdc_state *info = (void *)&dev->data; + struct device *udev = &info->control->dev; + + if (dev->driver_info->indication) { + dev->driver_info->indication(dev, msg, buflen); + } else { + u32 status = le32_to_cpu(msg->status); + + switch (status) { + case RNDIS_STATUS_MEDIA_CONNECT: + dev_info(udev, "rndis media connect\n"); + break; + case RNDIS_STATUS_MEDIA_DISCONNECT: + dev_info(udev, "rndis media disconnect\n"); + break; + default: + dev_info(udev, "rndis indication: 0x%08x\n", status); + } + } +} + +/* + * RPC done RNDIS-style. Caller guarantees: + * - message is properly byteswapped + * - there's no other request pending + * - buf can hold up to 1KB response (required by RNDIS spec) + * On return, the first few entries are already byteswapped. + * + * Call context is likely probe(), before interface name is known, + * which is why we won't try to use it in the diagnostics. + */ +int rndis_command(struct usbnet *dev, struct rndis_msg_hdr *buf, int buflen) +{ + struct cdc_state *info = (void *) &dev->data; + struct usb_cdc_notification notification; + int master_ifnum; + int retval; + int partial; + unsigned count; + u32 xid = 0, msg_len, request_id, msg_type, rsp, + status; + + /* REVISIT when this gets called from contexts other than probe() or + * disconnect(): either serialize, or dispatch responses on xid + */ + + msg_type = le32_to_cpu(buf->msg_type); + + /* Issue the request; xid is unique, don't bother byteswapping it */ + if (likely(msg_type != RNDIS_MSG_HALT && msg_type != RNDIS_MSG_RESET)) { + xid = dev->xid++; + if (!xid) + xid = dev->xid++; + buf->request_id = (__force __le32) xid; + } + master_ifnum = info->control->cur_altsetting->desc.bInterfaceNumber; + retval = usb_control_msg(dev->udev, + usb_sndctrlpipe(dev->udev, 0), + USB_CDC_SEND_ENCAPSULATED_COMMAND, + USB_TYPE_CLASS | USB_RECIP_INTERFACE, + 0, master_ifnum, + buf, le32_to_cpu(buf->msg_len), + RNDIS_CONTROL_TIMEOUT_MS); + if (unlikely(retval < 0 || xid == 0)) + return retval; + + /* Some devices don't respond on the control channel until + * polled on the status channel, so do that first. */ + if (dev->driver_info->data & RNDIS_DRIVER_DATA_POLL_STATUS) { + retval = usb_interrupt_msg( + dev->udev, + usb_rcvintpipe(dev->udev, + dev->status->desc.bEndpointAddress), + ¬ification, sizeof(notification), &partial, + RNDIS_CONTROL_TIMEOUT_MS); + if (unlikely(retval < 0)) + return retval; + } + + /* Poll the control channel; the request probably completed immediately */ + rsp = le32_to_cpu(buf->msg_type) | RNDIS_MSG_COMPLETION; + for (count = 0; count < 10; count++) { + memset(buf, 0, CONTROL_BUFFER_SIZE); + retval = usb_control_msg(dev->udev, + usb_rcvctrlpipe(dev->udev, 0), + USB_CDC_GET_ENCAPSULATED_RESPONSE, + USB_DIR_IN | USB_TYPE_CLASS | USB_RECIP_INTERFACE, + 0, master_ifnum, + buf, buflen, + RNDIS_CONTROL_TIMEOUT_MS); + if (likely(retval >= 8)) { + msg_type = le32_to_cpu(buf->msg_type); + msg_len = le32_to_cpu(buf->msg_len); + status = le32_to_cpu(buf->status); + request_id = (__force u32) buf->request_id; + if (likely(msg_type == rsp)) { + if (likely(request_id == xid)) { + if (unlikely(rsp == RNDIS_MSG_RESET_C)) + return 0; + if (likely(RNDIS_STATUS_SUCCESS == + status)) + return 0; + dev_dbg(&info->control->dev, + "rndis reply status %08x\n", + status); + return -EL3RST; + } + dev_dbg(&info->control->dev, + "rndis reply id %d expected %d\n", + request_id, xid); + /* then likely retry */ + } else switch (msg_type) { + case RNDIS_MSG_INDICATE: /* fault/event */ + rndis_msg_indicate(dev, (void *)buf, buflen); + break; + case RNDIS_MSG_KEEPALIVE: { /* ping */ + struct rndis_keepalive_c *msg = (void *)buf; + + msg->msg_type = cpu_to_le32(RNDIS_MSG_KEEPALIVE_C); + msg->msg_len = cpu_to_le32(sizeof *msg); + msg->status = cpu_to_le32(RNDIS_STATUS_SUCCESS); + retval = usb_control_msg(dev->udev, + usb_sndctrlpipe(dev->udev, 0), + USB_CDC_SEND_ENCAPSULATED_COMMAND, + USB_TYPE_CLASS | USB_RECIP_INTERFACE, + 0, master_ifnum, + msg, sizeof *msg, + RNDIS_CONTROL_TIMEOUT_MS); + if (unlikely(retval < 0)) + dev_dbg(&info->control->dev, + "rndis keepalive err %d\n", + retval); + } + break; + default: + dev_dbg(&info->control->dev, + "unexpected rndis msg %08x len %d\n", + le32_to_cpu(buf->msg_type), msg_len); + } + } else { + /* device probably issued a protocol stall; ignore */ + dev_dbg(&info->control->dev, + "rndis response error, code %d\n", retval); + } + msleep(20); + } + dev_dbg(&info->control->dev, "rndis response timeout\n"); + return -ETIMEDOUT; +} +EXPORT_SYMBOL_GPL(rndis_command); + +/* + * rndis_query: + * + * Performs a query for @oid along with 0 or more bytes of payload as + * specified by @in_len. If @reply_len is not set to -1 then the reply + * length is checked against this value, resulting in an error if it + * doesn't match. + * + * NOTE: Adding a payload exactly or greater than the size of the expected + * response payload is an evident requirement MSFT added for ActiveSync. + * + * The only exception is for OIDs that return a variably sized response, + * in which case no payload should be added. This undocumented (and + * nonsensical!) issue was found by sniffing protocol requests from the + * ActiveSync 4.1 Windows driver. + */ +static int rndis_query(struct usbnet *dev, struct usb_interface *intf, + void *buf, u32 oid, u32 in_len, + void **reply, int *reply_len) +{ + int retval; + union { + void *buf; + struct rndis_msg_hdr *header; + struct rndis_query *get; + struct rndis_query_c *get_c; + } u; + u32 off, len; + + u.buf = buf; + + memset(u.get, 0, sizeof *u.get + in_len); + u.get->msg_type = cpu_to_le32(RNDIS_MSG_QUERY); + u.get->msg_len = cpu_to_le32(sizeof *u.get + in_len); + u.get->oid = cpu_to_le32(oid); + u.get->len = cpu_to_le32(in_len); + u.get->offset = cpu_to_le32(20); + + retval = rndis_command(dev, u.header, CONTROL_BUFFER_SIZE); + if (unlikely(retval < 0)) { + dev_err(&intf->dev, "RNDIS_MSG_QUERY(0x%08x) failed, %d\n", + oid, retval); + return retval; + } + + off = le32_to_cpu(u.get_c->offset); + len = le32_to_cpu(u.get_c->len); + if (unlikely((8 + off + len) > CONTROL_BUFFER_SIZE)) + goto response_error; + + if (*reply_len != -1 && len != *reply_len) + goto response_error; + + *reply = (unsigned char *) &u.get_c->request_id + off; + *reply_len = len; + + return retval; + +response_error: + dev_err(&intf->dev, "RNDIS_MSG_QUERY(0x%08x) " + "invalid response - off %d len %d\n", + oid, off, len); + return -EDOM; +} + +/* same as usbnet_netdev_ops but MTU change not allowed */ +static const struct net_device_ops rndis_netdev_ops = { + .ndo_open = usbnet_open, + .ndo_stop = usbnet_stop, + .ndo_start_xmit = usbnet_start_xmit, + .ndo_tx_timeout = usbnet_tx_timeout, + .ndo_set_mac_address = eth_mac_addr, + .ndo_validate_addr = eth_validate_addr, +}; + +int +generic_rndis_bind(struct usbnet *dev, struct usb_interface *intf, int flags) +{ + int retval; + struct net_device *net = dev->net; + struct cdc_state *info = (void *) &dev->data; + union { + void *buf; + struct rndis_msg_hdr *header; + struct rndis_init *init; + struct rndis_init_c *init_c; + struct rndis_query *get; + struct rndis_query_c *get_c; + struct rndis_set *set; + struct rndis_set_c *set_c; + struct rndis_halt *halt; + } u; + u32 tmp; + __le32 phym_unspec, *phym; + int reply_len; + unsigned char *bp; + + /* we can't rely on i/o from stack working, or stack allocation */ + u.buf = kmalloc(CONTROL_BUFFER_SIZE, GFP_KERNEL); + if (!u.buf) + return -ENOMEM; + retval = usbnet_generic_cdc_bind(dev, intf); + if (retval < 0) + goto fail; + + u.init->msg_type = cpu_to_le32(RNDIS_MSG_INIT); + u.init->msg_len = cpu_to_le32(sizeof *u.init); + u.init->major_version = cpu_to_le32(1); + u.init->minor_version = cpu_to_le32(0); + + /* max transfer (in spec) is 0x4000 at full speed, but for + * TX we'll stick to one Ethernet packet plus RNDIS framing. + * For RX we handle drivers that zero-pad to end-of-packet. + * Don't let userspace change these settings. + * + * NOTE: there still seems to be wierdness here, as if we need + * to do some more things to make sure WinCE targets accept this. + * They default to jumbograms of 8KB or 16KB, which is absurd + * for such low data rates and which is also more than Linux + * can usually expect to allocate for SKB data... + */ + net->hard_header_len += sizeof (struct rndis_data_hdr); + dev->hard_mtu = net->mtu + net->hard_header_len; + + dev->maxpacket = usb_maxpacket(dev->udev, dev->out, 1); + if (dev->maxpacket == 0) { + netif_dbg(dev, probe, dev->net, + "dev->maxpacket can't be 0\n"); + retval = -EINVAL; + goto fail_and_release; + } + + dev->rx_urb_size = dev->hard_mtu + (dev->maxpacket + 1); + dev->rx_urb_size &= ~(dev->maxpacket - 1); + u.init->max_transfer_size = cpu_to_le32(dev->rx_urb_size); + + net->netdev_ops = &rndis_netdev_ops; + + retval = rndis_command(dev, u.header, CONTROL_BUFFER_SIZE); + if (unlikely(retval < 0)) { + /* it might not even be an RNDIS device!! */ + dev_err(&intf->dev, "RNDIS init failed, %d\n", retval); + goto fail_and_release; + } + tmp = le32_to_cpu(u.init_c->max_transfer_size); + if (tmp < dev->hard_mtu) { + if (tmp <= net->hard_header_len) { + dev_err(&intf->dev, + "dev can't take %u byte packets (max %u)\n", + dev->hard_mtu, tmp); + retval = -EINVAL; + goto halt_fail_and_release; + } + dev_warn(&intf->dev, + "dev can't take %u byte packets (max %u), " + "adjusting MTU to %u\n", + dev->hard_mtu, tmp, tmp - net->hard_header_len); + dev->hard_mtu = tmp; + net->mtu = dev->hard_mtu - net->hard_header_len; + } + + /* REVISIT: peripheral "alignment" request is ignored ... */ + dev_dbg(&intf->dev, + "hard mtu %u (%u from dev), rx buflen %zu, align %d\n", + dev->hard_mtu, tmp, dev->rx_urb_size, + 1 << le32_to_cpu(u.init_c->packet_alignment)); + + /* module has some device initialization code needs to be done right + * after RNDIS_INIT */ + if (dev->driver_info->early_init && + dev->driver_info->early_init(dev) != 0) + goto halt_fail_and_release; + + /* Check physical medium */ + phym = NULL; + reply_len = sizeof *phym; + retval = rndis_query(dev, intf, u.buf, + RNDIS_OID_GEN_PHYSICAL_MEDIUM, + 0, (void **) &phym, &reply_len); + if (retval != 0 || !phym) { + /* OID is optional so don't fail here. */ + phym_unspec = cpu_to_le32(RNDIS_PHYSICAL_MEDIUM_UNSPECIFIED); + phym = &phym_unspec; + } + if ((flags & FLAG_RNDIS_PHYM_WIRELESS) && + le32_to_cpup(phym) != RNDIS_PHYSICAL_MEDIUM_WIRELESS_LAN) { + netif_dbg(dev, probe, dev->net, + "driver requires wireless physical medium, but device is not\n"); + retval = -ENODEV; + goto halt_fail_and_release; + } + if ((flags & FLAG_RNDIS_PHYM_NOT_WIRELESS) && + le32_to_cpup(phym) == RNDIS_PHYSICAL_MEDIUM_WIRELESS_LAN) { + netif_dbg(dev, probe, dev->net, + "driver requires non-wireless physical medium, but device is wireless.\n"); + retval = -ENODEV; + goto halt_fail_and_release; + } + + /* Get designated host ethernet address */ + reply_len = ETH_ALEN; + retval = rndis_query(dev, intf, u.buf, + RNDIS_OID_802_3_PERMANENT_ADDRESS, + 48, (void **) &bp, &reply_len); + if (unlikely(retval< 0)) { + dev_err(&intf->dev, "rndis get ethaddr, %d\n", retval); + goto halt_fail_and_release; + } + + if (bp[0] & 0x02) + eth_hw_addr_random(net); + else + ether_addr_copy(net->dev_addr, bp); + + /* set a nonzero filter to enable data transfers */ + memset(u.set, 0, sizeof *u.set); + u.set->msg_type = cpu_to_le32(RNDIS_MSG_SET); + u.set->msg_len = cpu_to_le32(4 + sizeof *u.set); + u.set->oid = cpu_to_le32(RNDIS_OID_GEN_CURRENT_PACKET_FILTER); + u.set->len = cpu_to_le32(4); + u.set->offset = cpu_to_le32((sizeof *u.set) - 8); + *(__le32 *)(u.buf + sizeof *u.set) = cpu_to_le32(RNDIS_DEFAULT_FILTER); + + retval = rndis_command(dev, u.header, CONTROL_BUFFER_SIZE); + if (unlikely(retval < 0)) { + dev_err(&intf->dev, "rndis set packet filter, %d\n", retval); + goto halt_fail_and_release; + } + + retval = 0; + + kfree(u.buf); + return retval; + +halt_fail_and_release: + memset(u.halt, 0, sizeof *u.halt); + u.halt->msg_type = cpu_to_le32(RNDIS_MSG_HALT); + u.halt->msg_len = cpu_to_le32(sizeof *u.halt); + (void) rndis_command(dev, (void *)u.halt, CONTROL_BUFFER_SIZE); +fail_and_release: + usb_set_intfdata(info->data, NULL); + usb_driver_release_interface(driver_of(intf), info->data); + info->data = NULL; +fail: + kfree(u.buf); + return retval; +} +EXPORT_SYMBOL_GPL(generic_rndis_bind); + +static int rndis_bind(struct usbnet *dev, struct usb_interface *intf) +{ + return generic_rndis_bind(dev, intf, FLAG_RNDIS_PHYM_NOT_WIRELESS); +} + +void rndis_unbind(struct usbnet *dev, struct usb_interface *intf) +{ + struct rndis_halt *halt; + + /* try to clear any rndis state/activity (no i/o from stack!) */ + halt = kzalloc(CONTROL_BUFFER_SIZE, GFP_KERNEL); + if (halt) { + halt->msg_type = cpu_to_le32(RNDIS_MSG_HALT); + halt->msg_len = cpu_to_le32(sizeof *halt); + (void) rndis_command(dev, (void *)halt, CONTROL_BUFFER_SIZE); + kfree(halt); + } + + usbnet_cdc_unbind(dev, intf); +} +EXPORT_SYMBOL_GPL(rndis_unbind); + +/* + * DATA -- host must not write zlps + */ +int rndis_rx_fixup(struct usbnet *dev, struct sk_buff *skb) +{ + /* This check is no longer done by usbnet */ + if (skb->len < dev->net->hard_header_len) + return 0; + + /* peripheral may have batched packets to us... */ + while (likely(skb->len)) { + struct rndis_data_hdr *hdr = (void *)skb->data; + struct sk_buff *skb2; + u32 msg_type, msg_len, data_offset, data_len; + + msg_type = le32_to_cpu(hdr->msg_type); + msg_len = le32_to_cpu(hdr->msg_len); + data_offset = le32_to_cpu(hdr->data_offset); + data_len = le32_to_cpu(hdr->data_len); + + /* don't choke if we see oob, per-packet data, etc */ + if (unlikely(msg_type != RNDIS_MSG_PACKET || skb->len < msg_len + || (data_offset + data_len + 8) > msg_len)) { + dev->net->stats.rx_frame_errors++; + netdev_dbg(dev->net, "bad rndis message %d/%d/%d/%d, len %d\n", + le32_to_cpu(hdr->msg_type), + msg_len, data_offset, data_len, skb->len); + return 0; + } + skb_pull(skb, 8 + data_offset); + + /* at most one packet left? */ + if (likely((data_len - skb->len) <= sizeof *hdr)) { + skb_trim(skb, data_len); + break; + } + + /* try to return all the packets in the batch */ + skb2 = skb_clone(skb, GFP_ATOMIC); + if (unlikely(!skb2)) + break; + skb_pull(skb, msg_len - sizeof *hdr); + skb_trim(skb2, data_len); + usbnet_skb_return(dev, skb2); + } + + /* caller will usbnet_skb_return the remaining packet */ + return 1; +} +EXPORT_SYMBOL_GPL(rndis_rx_fixup); + +struct sk_buff * +rndis_tx_fixup(struct usbnet *dev, struct sk_buff *skb, gfp_t flags) +{ + struct rndis_data_hdr *hdr; + struct sk_buff *skb2; + unsigned len = skb->len; + + if (likely(!skb_cloned(skb))) { + int room = skb_headroom(skb); + + /* enough head room as-is? */ + if (unlikely((sizeof *hdr) <= room)) + goto fill; + + /* enough room, but needs to be readjusted? */ + room += skb_tailroom(skb); + if (likely((sizeof *hdr) <= room)) { + skb->data = memmove(skb->head + sizeof *hdr, + skb->data, len); + skb_set_tail_pointer(skb, len); + goto fill; + } + } + + /* create a new skb, with the correct size (and tailpad) */ + skb2 = skb_copy_expand(skb, sizeof *hdr, 1, flags); + dev_kfree_skb_any(skb); + if (unlikely(!skb2)) + return skb2; + skb = skb2; + + /* fill out the RNDIS header. we won't bother trying to batch + * packets; Linux minimizes wasted bandwidth through tx queues. + */ +fill: + hdr = (void *) __skb_push(skb, sizeof *hdr); + memset(hdr, 0, sizeof *hdr); + hdr->msg_type = cpu_to_le32(RNDIS_MSG_PACKET); + hdr->msg_len = cpu_to_le32(skb->len); + hdr->data_offset = cpu_to_le32(sizeof(*hdr) - 8); + hdr->data_len = cpu_to_le32(len); + + /* FIXME make the last packet always be short ... */ + return skb; +} +EXPORT_SYMBOL_GPL(rndis_tx_fixup); + + +static const struct driver_info rndis_info = { + .description = "RNDIS device", + .flags = FLAG_ETHER | FLAG_POINTTOPOINT | FLAG_FRAMING_RN | FLAG_NO_SETINT, + .bind = rndis_bind, + .unbind = rndis_unbind, + .status = rndis_status, + .rx_fixup = rndis_rx_fixup, + .tx_fixup = rndis_tx_fixup, +}; + +static const struct driver_info rndis_poll_status_info = { + .description = "RNDIS device (poll status before control)", + .flags = FLAG_ETHER | FLAG_POINTTOPOINT | FLAG_FRAMING_RN | FLAG_NO_SETINT, + .data = RNDIS_DRIVER_DATA_POLL_STATUS, + .bind = rndis_bind, + .unbind = rndis_unbind, + .status = rndis_status, + .rx_fixup = rndis_rx_fixup, + .tx_fixup = rndis_tx_fixup, +}; + +/*-------------------------------------------------------------------------*/ + +static const struct usb_device_id products [] = { +{ + /* 2Wire HomePortal 1000SW */ + USB_DEVICE_AND_INTERFACE_INFO(0x1630, 0x0042, + USB_CLASS_COMM, 2 /* ACM */, 0x0ff), + .driver_info = (unsigned long) &rndis_poll_status_info, +}, { + /* RNDIS is MSFT's un-official variant of CDC ACM */ + USB_INTERFACE_INFO(USB_CLASS_COMM, 2 /* ACM */, 0x0ff), + .driver_info = (unsigned long) &rndis_info, +}, { + /* "ActiveSync" is an undocumented variant of RNDIS, used in WM5 */ + USB_INTERFACE_INFO(USB_CLASS_MISC, 1, 1), + .driver_info = (unsigned long) &rndis_poll_status_info, +}, { + /* RNDIS for tethering */ + USB_INTERFACE_INFO(USB_CLASS_WIRELESS_CONTROLLER, 1, 3), + .driver_info = (unsigned long) &rndis_info, +}, + { }, // END +}; +MODULE_DEVICE_TABLE(usb, products); + +static struct usb_driver rndis_driver = { + .name = "rndis_host", + .id_table = products, + .probe = usbnet_probe, + .disconnect = usbnet_disconnect, + .suspend = usbnet_suspend, + .resume = usbnet_resume, + .disable_hub_initiated_lpm = 1, +}; + +module_usb_driver(rndis_driver); + +MODULE_AUTHOR("David Brownell"); +MODULE_DESCRIPTION("USB Host side RNDIS driver"); +MODULE_LICENSE("GPL"); -- cgit v1.2.3