diff options
Diffstat (limited to 'drivers/staging/rtl8188eu/os_dep/mon.c')
-rw-r--r-- | drivers/staging/rtl8188eu/os_dep/mon.c | 195 |
1 files changed, 195 insertions, 0 deletions
diff --git a/drivers/staging/rtl8188eu/os_dep/mon.c b/drivers/staging/rtl8188eu/os_dep/mon.c new file mode 100644 index 000000000..63bb87593 --- /dev/null +++ b/drivers/staging/rtl8188eu/os_dep/mon.c @@ -0,0 +1,195 @@ +/* + * RTL8188EU monitor interface + * + * Copyright (C) 2015 Jakub Sitnicki + * + * 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. + * + * 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. + */ + +#include <linux/ieee80211.h> +#include <linux/netdevice.h> +#include <net/cfg80211.h> + +#include <drv_types.h> +#include <rtw_recv.h> +#include <rtw_xmit.h> +#include <mon.h> + +/** + * unprotect_frame() - unset Protected flag and strip off IV and ICV/MIC + */ +static void unprotect_frame(struct sk_buff *skb, int iv_len, int icv_len) +{ + struct ieee80211_hdr *hdr; + int hdr_len; + + hdr = (struct ieee80211_hdr *)skb->data; + hdr_len = ieee80211_hdrlen(hdr->frame_control); + + if (skb->len < hdr_len + iv_len + icv_len) + return; + if (!ieee80211_has_protected(hdr->frame_control)) + return; + + hdr->frame_control &= ~cpu_to_le16(IEEE80211_FCTL_PROTECTED); + + memmove(skb->data + iv_len, skb->data, hdr_len); + skb_pull(skb, iv_len); + skb_trim(skb, skb->len - icv_len); +} + +static void mon_recv_decrypted(struct net_device *dev, const u8 *data, + int data_len, int iv_len, int icv_len) +{ + struct sk_buff *skb; + + skb = netdev_alloc_skb(dev, data_len); + if (!skb) + return; + memcpy(skb_put(skb, data_len), data, data_len); + + /* + * Frame data is not encrypted. Strip off protection so + * userspace doesn't think that it is. + */ + unprotect_frame(skb, iv_len, icv_len); + + skb->ip_summed = CHECKSUM_UNNECESSARY; + skb->protocol = eth_type_trans(skb, dev); + netif_rx(skb); +} + +static void mon_recv_encrypted(struct net_device *dev, const u8 *data, + int data_len) +{ + if (net_ratelimit()) + netdev_info(dev, "Encrypted packets are not supported"); +} + +/** + * rtl88eu_mon_recv_hook() - forward received frame to the monitor interface + * + * Assumes that the frame contains an IV and an ICV/MIC, and that + * encrypt field in frame->attrib have been set accordingly. + */ +void rtl88eu_mon_recv_hook(struct net_device *dev, struct recv_frame *frame) +{ + struct rx_pkt_attrib *attr; + int iv_len, icv_len; + int data_len; + u8 *data; + + if (!dev || !frame) + return; + if (!netif_running(dev)) + return; + + attr = &frame->attrib; + data = frame->rx_data; + data_len = frame->len; + + /* Broadcast and multicast frames don't have attr->{iv,icv}_len set */ + SET_ICE_IV_LEN(iv_len, icv_len, attr->encrypt); + + if (attr->bdecrypted) + mon_recv_decrypted(dev, data, data_len, iv_len, icv_len); + else + mon_recv_encrypted(dev, data, data_len); +} + +/** + * rtl88eu_mon_xmit_hook() - forward trasmitted frame to the monitor interface + * + * Assumes that: + * - frame header contains an IV and frame->attrib.iv_len is set accordingly, + * - data is not encrypted and ICV/MIC has not been appended yet. + */ +void rtl88eu_mon_xmit_hook(struct net_device *dev, struct xmit_frame *frame, + uint frag_len) +{ + struct pkt_attrib *attr; + u8 *data; + int i, offset; + + if (!dev || !frame) + return; + if (!netif_running(dev)) + return; + + attr = &frame->attrib; + + offset = TXDESC_SIZE + frame->pkt_offset * PACKET_OFFSET_SZ; + data = frame->buf_addr + offset; + + for (i = 0; i < attr->nr_frags - 1; i++) { + mon_recv_decrypted(dev, data, frag_len, attr->iv_len, 0); + data += frag_len; + data = (u8 *)round_up((size_t)data, 4); + } + /* Last fragment has different length */ + mon_recv_decrypted(dev, data, attr->last_txcmdsz, attr->iv_len, 0); +} + +static netdev_tx_t mon_xmit(struct sk_buff *skb, struct net_device *dev) +{ + dev_kfree_skb(skb); + return NETDEV_TX_OK; +} + +static const struct net_device_ops mon_netdev_ops = { + .ndo_start_xmit = mon_xmit, + .ndo_change_mtu = eth_change_mtu, + .ndo_set_mac_address = eth_mac_addr, + .ndo_validate_addr = eth_validate_addr, +}; + +static void mon_setup(struct net_device *dev) +{ + dev->netdev_ops = &mon_netdev_ops; + dev->destructor = free_netdev; + ether_setup(dev); + dev->tx_queue_len = 0; + dev->type = ARPHRD_IEEE80211; + /* + * Use a locally administered address (IEEE 802) + * XXX: Copied from mac80211_hwsim driver. Revisit. + */ + eth_zero_addr(dev->dev_addr); + dev->dev_addr[0] = 0x12; +} + +struct net_device *rtl88eu_mon_init(void) +{ + struct net_device *dev; + int err; + + dev = alloc_netdev(0, "mon%d", NET_NAME_UNKNOWN, mon_setup); + if (!dev) + goto fail; + + err = register_netdev(dev); + if (err < 0) + goto fail_free_dev; + + return dev; + +fail_free_dev: + free_netdev(dev); +fail: + return NULL; +} + +void rtl88eu_mon_deinit(struct net_device *dev) +{ + if (!dev) + return; + + unregister_netdev(dev); +} |