+++ /dev/null
-/*
- * WiMedia Logical Link Control Protocol (WLP)
- * Message exchange infrastructure
- *
- * Copyright (C) 2007 Intel Corporation
- * Reinette Chatre <reinette.chatre@intel.com>
- *
- * 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.
- *
- * You should have received a copy of the GNU General Public License
- * along with this program; if not, write to the Free Software
- * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA
- * 02110-1301, USA.
- *
- *
- * FIXME: Docs
- *
- */
-
-#include <linux/etherdevice.h>
-#include <linux/slab.h>
-#include <linux/wlp.h>
-
-#include "wlp-internal.h"
-
-/*
- * Direct incoming association msg to correct parsing routine
- *
- * We only expect D1, E1, C1, C3 messages as new. All other incoming
- * association messages should form part of an established session that is
- * handled elsewhere.
- * The handling of these messages often require calling sleeping functions
- * - this cannot be done in interrupt context. We use the kernel's
- * workqueue to handle these messages.
- */
-static
-void wlp_direct_assoc_frame(struct wlp *wlp, struct sk_buff *skb,
- struct uwb_dev_addr *src)
-{
- struct device *dev = &wlp->rc->uwb_dev.dev;
- struct wlp_frame_assoc *assoc = (void *) skb->data;
- struct wlp_assoc_frame_ctx *frame_ctx;
-
- frame_ctx = kmalloc(sizeof(*frame_ctx), GFP_ATOMIC);
- if (frame_ctx == NULL) {
- dev_err(dev, "WLP: Unable to allocate memory for association "
- "frame handling.\n");
- kfree_skb(skb);
- return;
- }
- frame_ctx->wlp = wlp;
- frame_ctx->skb = skb;
- frame_ctx->src = *src;
- switch (assoc->type) {
- case WLP_ASSOC_D1:
- INIT_WORK(&frame_ctx->ws, wlp_handle_d1_frame);
- schedule_work(&frame_ctx->ws);
- break;
- case WLP_ASSOC_E1:
- kfree_skb(skb); /* Temporary until we handle it */
- kfree(frame_ctx); /* Temporary until we handle it */
- break;
- case WLP_ASSOC_C1:
- INIT_WORK(&frame_ctx->ws, wlp_handle_c1_frame);
- schedule_work(&frame_ctx->ws);
- break;
- case WLP_ASSOC_C3:
- INIT_WORK(&frame_ctx->ws, wlp_handle_c3_frame);
- schedule_work(&frame_ctx->ws);
- break;
- default:
- dev_err(dev, "Received unexpected association frame. "
- "Type = %d \n", assoc->type);
- kfree_skb(skb);
- kfree(frame_ctx);
- break;
- }
-}
-
-/*
- * Process incoming association frame
- *
- * Although it could be possible to deal with some incoming association
- * messages without creating a new session we are keeping things simple. We
- * do not accept new association messages if there is a session in progress
- * and the messages do not belong to that session.
- *
- * If an association message arrives that causes the creation of a session
- * (WLP_ASSOC_E1) while we are in the process of creating a session then we
- * rely on the neighbor mutex to protect the data. That is, the new session
- * will not be started until the previous is completed.
- */
-static
-void wlp_receive_assoc_frame(struct wlp *wlp, struct sk_buff *skb,
- struct uwb_dev_addr *src)
-{
- struct device *dev = &wlp->rc->uwb_dev.dev;
- struct wlp_frame_assoc *assoc = (void *) skb->data;
- struct wlp_session *session = wlp->session;
- u8 version;
-
- if (wlp_get_version(wlp, &assoc->version, &version,
- sizeof(assoc->version)) < 0)
- goto error;
- if (version != WLP_VERSION) {
- dev_err(dev, "Unsupported WLP version in association "
- "message.\n");
- goto error;
- }
- if (session != NULL) {
- /* Function that created this session is still holding the
- * &wlp->mutex to protect this session. */
- if (assoc->type == session->exp_message ||
- assoc->type == WLP_ASSOC_F0) {
- if (!memcmp(&session->neighbor_addr, src,
- sizeof(*src))) {
- session->data = skb;
- (session->cb)(wlp);
- } else {
- dev_err(dev, "Received expected message from "
- "unexpected source. Expected message "
- "%d or F0 from %02x:%02x, but received "
- "it from %02x:%02x. Dropping.\n",
- session->exp_message,
- session->neighbor_addr.data[1],
- session->neighbor_addr.data[0],
- src->data[1], src->data[0]);
- goto error;
- }
- } else {
- dev_err(dev, "Association already in progress. "
- "Dropping.\n");
- goto error;
- }
- } else {
- wlp_direct_assoc_frame(wlp, skb, src);
- }
- return;
-error:
- kfree_skb(skb);
-}
-
-/*
- * Verify incoming frame is from connected neighbor, prep to pass to WLP client
- *
- * Verification proceeds according to WLP 0.99 [7.3.1]. The source address
- * is used to determine which neighbor is sending the frame and the WSS tag
- * is used to know to which WSS the frame belongs (we only support one WSS
- * so this test is straight forward).
- * With the WSS found we need to ensure that we are connected before
- * allowing the exchange of data frames.
- */
-static
-int wlp_verify_prep_rx_frame(struct wlp *wlp, struct sk_buff *skb,
- struct uwb_dev_addr *src)
-{
- struct device *dev = &wlp->rc->uwb_dev.dev;
- int result = -EINVAL;
- struct wlp_eda_node eda_entry;
- struct wlp_frame_std_abbrv_hdr *hdr = (void *) skb->data;
-
- /*verify*/
- result = wlp_copy_eda_node(&wlp->eda, src, &eda_entry);
- if (result < 0) {
- if (printk_ratelimit())
- dev_err(dev, "WLP: Incoming frame is from unknown "
- "neighbor %02x:%02x.\n", src->data[1],
- src->data[0]);
- goto out;
- }
- if (hdr->tag != eda_entry.tag) {
- if (printk_ratelimit())
- dev_err(dev, "WLP: Tag of incoming frame from "
- "%02x:%02x does not match expected tag. "
- "Received 0x%02x, expected 0x%02x. \n",
- src->data[1], src->data[0], hdr->tag,
- eda_entry.tag);
- result = -EINVAL;
- goto out;
- }
- if (eda_entry.state != WLP_WSS_CONNECTED) {
- if (printk_ratelimit())
- dev_err(dev, "WLP: Incoming frame from "
- "%02x:%02x does is not from connected WSS.\n",
- src->data[1], src->data[0]);
- result = -EINVAL;
- goto out;
- }
- /*prep*/
- skb_pull(skb, sizeof(*hdr));
-out:
- return result;
-}
-
-/*
- * Receive a WLP frame from device
- *
- * @returns: 1 if calling function should free the skb
- * 0 if it successfully handled skb and freed it
- * 0 if error occured, will free skb in this case
- */
-int wlp_receive_frame(struct device *dev, struct wlp *wlp, struct sk_buff *skb,
- struct uwb_dev_addr *src)
-{
- unsigned len = skb->len;
- void *ptr = skb->data;
- struct wlp_frame_hdr *hdr;
- int result = 0;
-
- if (len < sizeof(*hdr)) {
- dev_err(dev, "Not enough data to parse WLP header.\n");
- result = -EINVAL;
- goto out;
- }
- hdr = ptr;
- if (le16_to_cpu(hdr->mux_hdr) != WLP_PROTOCOL_ID) {
- dev_err(dev, "Not a WLP frame type.\n");
- result = -EINVAL;
- goto out;
- }
- switch (hdr->type) {
- case WLP_FRAME_STANDARD:
- if (len < sizeof(struct wlp_frame_std_abbrv_hdr)) {
- dev_err(dev, "Not enough data to parse Standard "
- "WLP header.\n");
- goto out;
- }
- result = wlp_verify_prep_rx_frame(wlp, skb, src);
- if (result < 0) {
- if (printk_ratelimit())
- dev_err(dev, "WLP: Verification of frame "
- "from neighbor %02x:%02x failed.\n",
- src->data[1], src->data[0]);
- goto out;
- }
- result = 1;
- break;
- case WLP_FRAME_ABBREVIATED:
- dev_err(dev, "Abbreviated frame received. FIXME?\n");
- kfree_skb(skb);
- break;
- case WLP_FRAME_CONTROL:
- dev_err(dev, "Control frame received. FIXME?\n");
- kfree_skb(skb);
- break;
- case WLP_FRAME_ASSOCIATION:
- if (len < sizeof(struct wlp_frame_assoc)) {
- dev_err(dev, "Not enough data to parse Association "
- "WLP header.\n");
- goto out;
- }
- wlp_receive_assoc_frame(wlp, skb, src);
- break;
- default:
- dev_err(dev, "Invalid frame received.\n");
- result = -EINVAL;
- break;
- }
-out:
- if (result < 0) {
- kfree_skb(skb);
- result = 0;
- }
- return result;
-}
-EXPORT_SYMBOL_GPL(wlp_receive_frame);
-
-
-/*
- * Verify frame from network stack, prepare for further transmission
- *
- * @skb: the socket buffer that needs to be prepared for transmission (it
- * is in need of a WLP header). If this is a broadcast frame we take
- * over the entire transmission.
- * If it is a unicast the WSS connection should already be established
- * and transmission will be done by the calling function.
- * @dst: On return this will contain the device address to which the
- * frame is destined.
- * @returns: 0 on success no tx : WLP header successfully applied to skb buffer,
- * calling function can proceed with tx
- * 1 on success with tx : WLP will take over transmission of this
- * frame
- * <0 on error
- *
- * The network stack (WLP client) is attempting to transmit a frame. We can
- * only transmit data if a local WSS is at least active (connection will be
- * done here if this is a broadcast frame and neighbor also has the WSS
- * active).
- *
- * The frame can be either broadcast or unicast. Broadcast in a WSS is
- * supported via multicast, but we don't support multicast yet (until
- * devices start to support MAB IEs). If a broadcast frame needs to be
- * transmitted it is treated as a unicast frame to each neighbor. In this
- * case the WLP takes over transmission of the skb and returns 1
- * to the caller to indicate so. Also, in this case, if a neighbor has the
- * same WSS activated but is not connected then the WSS connection will be
- * done at this time. The neighbor's virtual address will be learned at
- * this time.
- *
- * The destination address in a unicast frame is the virtual address of the
- * neighbor. This address only becomes known when a WSS connection is
- * established. We thus rely on a broadcast frame to trigger the setup of
- * WSS connections to all neighbors before we are able to send unicast
- * frames to them. This seems reasonable as IP would usually use ARP first
- * before any unicast frames are sent.
- *
- * If we are already connected to the neighbor (neighbor's virtual address
- * is known) we just prepare the WLP header and the caller will continue to
- * send the frame.
- *
- * A failure in this function usually indicates something that cannot be
- * fixed automatically. So, if this function fails (@return < 0) the calling
- * function should not retry to send the frame as it will very likely keep
- * failing.
- *
- */
-int wlp_prepare_tx_frame(struct device *dev, struct wlp *wlp,
- struct sk_buff *skb, struct uwb_dev_addr *dst)
-{
- int result = -EINVAL;
- struct ethhdr *eth_hdr = (void *) skb->data;
-
- if (is_multicast_ether_addr(eth_hdr->h_dest)) {
- result = wlp_eda_for_each(&wlp->eda, wlp_wss_send_copy, skb);
- if (result < 0) {
- if (printk_ratelimit())
- dev_err(dev, "Unable to handle broadcast "
- "frame from WLP client.\n");
- goto out;
- }
- dev_kfree_skb_irq(skb);
- result = 1;
- /* Frame will be transmitted by WLP. */
- } else {
- result = wlp_eda_for_virtual(&wlp->eda, eth_hdr->h_dest, dst,
- wlp_wss_prep_hdr, skb);
- if (unlikely(result < 0)) {
- if (printk_ratelimit())
- dev_err(dev, "Unable to prepare "
- "skb for transmission. \n");
- goto out;
- }
- }
-out:
- return result;
-}
-EXPORT_SYMBOL_GPL(wlp_prepare_tx_frame);
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