diff options
Diffstat (limited to 'drivers/uwb/wlp/wss-lc.c')
| -rw-r--r-- | drivers/uwb/wlp/wss-lc.c | 1055 |
1 files changed, 1055 insertions, 0 deletions
diff --git a/drivers/uwb/wlp/wss-lc.c b/drivers/uwb/wlp/wss-lc.c new file mode 100644 index 000000000000..96b18c9bd6e9 --- /dev/null +++ b/drivers/uwb/wlp/wss-lc.c @@ -0,0 +1,1055 @@ +/* + * WiMedia Logical Link Control Protocol (WLP) + * + * 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. + * + * + * Implementation of the WLP association protocol. + * + * FIXME: Docs + * + * A UWB network interface will configure a WSS through wlp_wss_setup() after + * the interface has been assigned a MAC address, typically after + * "ifconfig" has been called. When the interface goes down it should call + * wlp_wss_remove(). + * + * When the WSS is ready for use the user interacts via sysfs to create, + * discover, and activate WSS. + * + * wlp_wss_enroll_activate() + * + * wlp_wss_create_activate() + * wlp_wss_set_wssid_hash() + * wlp_wss_comp_wssid_hash() + * wlp_wss_sel_bcast_addr() + * wlp_wss_sysfs_add() + * + * Called when no more references to WSS exist: + * wlp_wss_release() + * wlp_wss_reset() + */ + +#include <linux/etherdevice.h> /* for is_valid_ether_addr */ +#include <linux/skbuff.h> +#include <linux/wlp.h> +#define D_LOCAL 5 +#include <linux/uwb/debug.h> +#include "wlp-internal.h" + + +size_t wlp_wss_key_print(char *buf, size_t bufsize, u8 *key) +{ + size_t result; + + result = scnprintf(buf, bufsize, + "%02x %02x %02x %02x %02x %02x " + "%02x %02x %02x %02x %02x %02x " + "%02x %02x %02x %02x", + key[0], key[1], key[2], key[3], + key[4], key[5], key[6], key[7], + key[8], key[9], key[10], key[11], + key[12], key[13], key[14], key[15]); + return result; +} + +/** + * Compute WSSID hash + * WLP Draft 0.99 [7.2.1] + * + * The WSSID hash for a WSSID is the result of an octet-wise exclusive-OR + * of all octets in the WSSID. + */ +static +u8 wlp_wss_comp_wssid_hash(struct wlp_uuid *wssid) +{ + return wssid->data[0] ^ wssid->data[1] ^ wssid->data[2] + ^ wssid->data[3] ^ wssid->data[4] ^ wssid->data[5] + ^ wssid->data[6] ^ wssid->data[7] ^ wssid->data[8] + ^ wssid->data[9] ^ wssid->data[10] ^ wssid->data[11] + ^ wssid->data[12] ^ wssid->data[13] ^ wssid->data[14] + ^ wssid->data[15]; +} + +/** + * Select a multicast EUI-48 for the WSS broadcast address. + * WLP Draft 0.99 [7.2.1] + * + * Selected based on the WiMedia Alliance OUI, 00-13-88, within the WLP + * range, [01-13-88-00-01-00, 01-13-88-00-01-FF] inclusive. + * + * This address is currently hardcoded. + * FIXME? + */ +static +struct uwb_mac_addr wlp_wss_sel_bcast_addr(struct wlp_wss *wss) +{ + struct uwb_mac_addr bcast = { + .data = { 0x01, 0x13, 0x88, 0x00, 0x01, 0x00 } + }; + return bcast; +} + +/** + * Clear the contents of the WSS structure - all except kobj, mutex, virtual + * + * We do not want to reinitialize - the internal kobj should not change as + * it still points to the parent received during setup. The mutex should + * remain also. We thus just reset values individually. + * The virutal address assigned to WSS will remain the same for the + * lifetime of the WSS. We only reset the fields that can change during its + * lifetime. + */ +void wlp_wss_reset(struct wlp_wss *wss) +{ + struct wlp *wlp = container_of(wss, struct wlp, wss); + struct device *dev = &wlp->rc->uwb_dev.dev; + d_fnstart(5, dev, "wss (%p) \n", wss); + memset(&wss->wssid, 0, sizeof(wss->wssid)); + wss->hash = 0; + memset(&wss->name[0], 0, sizeof(wss->name)); + memset(&wss->bcast, 0, sizeof(wss->bcast)); + wss->secure_status = WLP_WSS_UNSECURE; + memset(&wss->master_key[0], 0, sizeof(wss->master_key)); + wss->tag = 0; + wss->state = WLP_WSS_STATE_NONE; + d_fnend(5, dev, "wss (%p) \n", wss); +} + +/** + * Create sysfs infrastructure for WSS + * + * The WSS is configured to have the interface as parent (see wlp_wss_setup()) + * a new sysfs directory that includes wssid as its name is created in the + * interface's sysfs directory. The group of files interacting with WSS are + * created also. + */ +static +int wlp_wss_sysfs_add(struct wlp_wss *wss, char *wssid_str) +{ + struct wlp *wlp = container_of(wss, struct wlp, wss); + struct device *dev = &wlp->rc->uwb_dev.dev; + int result; + + d_fnstart(5, dev, "wss (%p), wssid: %s\n", wss, wssid_str); + result = kobject_set_name(&wss->kobj, "wss-%s", wssid_str); + if (result < 0) + return result; + wss->kobj.ktype = &wss_ktype; + result = kobject_init_and_add(&wss->kobj, + &wss_ktype, wss->kobj.parent, "wlp"); + if (result < 0) { + dev_err(dev, "WLP: Cannot register WSS kobject.\n"); + goto error_kobject_register; + } + result = sysfs_create_group(&wss->kobj, &wss_attr_group); + if (result < 0) { + dev_err(dev, "WLP: Cannot register WSS attributes: %d\n", + result); + goto error_sysfs_create_group; + } + d_fnend(5, dev, "Completed. result = %d \n", result); + return 0; +error_sysfs_create_group: + + kobject_put(&wss->kobj); /* will free name if needed */ + return result; +error_kobject_register: + kfree(wss->kobj.name); + wss->kobj.name = NULL; + wss->kobj.ktype = NULL; + return result; +} + + +/** + * Release WSS + * + * No more references exist to this WSS. We should undo everything that was + * done in wlp_wss_create_activate() except removing the group. The group + * is not removed because an object can be unregistered before the group is + * created. We also undo any additional operations on the WSS after this + * (addition of members). + * + * If memory was allocated for the kobject's name then it will + * be freed by the kobject system during this time. + * + * The EDA cache is removed and reinitilized when the WSS is removed. We + * thus loose knowledge of members of this WSS at that time and need not do + * it here. + */ +void wlp_wss_release(struct kobject *kobj) +{ + struct wlp_wss *wss = container_of(kobj, struct wlp_wss, kobj); + + wlp_wss_reset(wss); +} + +/** + * Enroll into a WSS using provided neighbor as registrar + * + * First search the neighborhood information to learn which neighbor is + * referred to, next proceed with enrollment. + * + * &wss->mutex is held + */ +static +int wlp_wss_enroll_target(struct wlp_wss *wss, struct wlp_uuid *wssid, + struct uwb_dev_addr *dest) +{ + struct wlp *wlp = container_of(wss, struct wlp, wss); + struct device *dev = &wlp->rc->uwb_dev.dev; + struct wlp_neighbor_e *neighbor; + char buf[WLP_WSS_UUID_STRSIZE]; + int result = -ENXIO; + struct uwb_dev_addr *dev_addr; + + wlp_wss_uuid_print(buf, sizeof(buf), wssid); + d_fnstart(5, dev, "wss %p, wssid %s, registrar %02x:%02x \n", + wss, buf, dest->data[1], dest->data[0]); + mutex_lock(&wlp->nbmutex); + list_for_each_entry(neighbor, &wlp->neighbors, node) { + dev_addr = &neighbor->uwb_dev->dev_addr; + if (!memcmp(dest, dev_addr, sizeof(*dest))) { + d_printf(5, dev, "Neighbor %02x:%02x is valid, " + "enrolling. \n", + dev_addr->data[1], dev_addr->data[0]); + result = wlp_enroll_neighbor(wlp, neighbor, wss, + wssid); + break; + } + } + if (result == -ENXIO) + dev_err(dev, "WLP: Cannot find neighbor %02x:%02x. \n", + dest->data[1], dest->data[0]); + mutex_unlock(&wlp->nbmutex); + d_fnend(5, dev, "wss %p, wssid %s, registrar %02x:%02x, result %d \n", + wss, buf, dest->data[1], dest->data[0], result); + return result; +} + +/** + * Enroll into a WSS previously discovered + * + * User provides WSSID of WSS, search for neighbor that has this WSS + * activated and attempt to enroll. + * + * &wss->mutex is held + */ +static +int wlp_wss_enroll_discovered(struct wlp_wss *wss, struct wlp_uuid *wssid) +{ + struct wlp *wlp = container_of(wss, struct wlp, wss); + struct device *dev = &wlp->rc->uwb_dev.dev; + struct wlp_neighbor_e *neighbor; + struct wlp_wssid_e *wssid_e; + char buf[WLP_WSS_UUID_STRSIZE]; + int result = -ENXIO; + + wlp_wss_uuid_print(buf, sizeof(buf), wssid); + d_fnstart(5, dev, "wss %p, wssid %s \n", wss, buf); + mutex_lock(&wlp->nbmutex); + list_for_each_entry(neighbor, &wlp->neighbors, node) { + list_for_each_entry(wssid_e, &neighbor->wssid, node) { + if (!memcmp(wssid, &wssid_e->wssid, sizeof(*wssid))) { + d_printf(5, dev, "Found WSSID %s in neighbor " + "%02x:%02x cache. \n", buf, + neighbor->uwb_dev->dev_addr.data[1], + neighbor->uwb_dev->dev_addr.data[0]); + result = wlp_enroll_neighbor(wlp, neighbor, + wss, wssid); + if (result == 0) /* enrollment success */ + goto out; + break; + } + } + } +out: + if (result == -ENXIO) + dev_err(dev, "WLP: Cannot find WSSID %s in cache. \n", buf); + mutex_unlock(&wlp->nbmutex); + d_fnend(5, dev, "wss %p, wssid %s, result %d \n", wss, buf, result); + return result; +} + +/** + * Enroll into WSS with provided WSSID, registrar may be provided + * + * @wss: out WSS that will be enrolled + * @wssid: wssid of neighboring WSS that we want to enroll in + * @devaddr: registrar can be specified, will be broadcast (ff:ff) if any + * neighbor can be used as registrar. + * + * &wss->mutex is held + */ +static +int wlp_wss_enroll(struct wlp_wss *wss, struct wlp_uuid *wssid, + struct uwb_dev_addr *devaddr) +{ + int result; + struct wlp *wlp = container_of(wss, struct wlp, wss); + struct device *dev = &wlp->rc->uwb_dev.dev; + char buf[WLP_WSS_UUID_STRSIZE]; + struct uwb_dev_addr bcast = {.data = {0xff, 0xff} }; + + wlp_wss_uuid_print(buf, sizeof(buf), wssid); + if (wss->state != WLP_WSS_STATE_NONE) { + dev_err(dev, "WLP: Already enrolled in WSS %s.\n", buf); + result = -EEXIST; + goto error; + } + if (!memcmp(&bcast, devaddr, sizeof(bcast))) { + d_printf(5, dev, "Request to enroll in discovered WSS " + "with WSSID %s \n", buf); + result = wlp_wss_enroll_discovered(wss, wssid); + } else { + d_printf(5, dev, "Request to enroll in WSSID %s with " + "registrar %02x:%02x\n", buf, devaddr->data[1], + devaddr->data[0]); + result = wlp_wss_enroll_target(wss, wssid, devaddr); + } + if (result < 0) { + dev_err(dev, "WLP: Unable to enroll into WSS %s, result %d \n", + buf, result); + goto error; + } + d_printf(2, dev, "Successfully enrolled into WSS %s \n", buf); + result = wlp_wss_sysfs_add(wss, buf); + if (result < 0) { + dev_err(dev, "WLP: Unable to set up sysfs for WSS kobject.\n"); + wlp_wss_reset(wss); + } +error: + return result; + +} + +/** + * Activate given WSS + * + * Prior to activation a WSS must be enrolled. To activate a WSS a device + * includes the WSS hash in the WLP IE in its beacon in each superframe. + * WLP 0.99 [7.2.5]. + * + * The WSS tag is also computed at this time. We only support one activated + * WSS so we can use the hash as a tag - there will never be a conflict. + * + * We currently only support one activated WSS so only one WSS hash is + * included in the WLP IE. + */ +static +int wlp_wss_activate(struct wlp_wss *wss) +{ + struct wlp *wlp = container_of(wss, struct wlp, wss); + struct device *dev = &wlp->rc->uwb_dev.dev; + struct uwb_rc *uwb_rc = wlp->rc; + int result; + struct { + struct wlp_ie wlp_ie; + u8 hash; /* only include one hash */ + } ie_data; + + d_fnstart(5, dev, "Activating WSS %p. \n", wss); + BUG_ON(wss->state != WLP_WSS_STATE_ENROLLED); + wss->hash = wlp_wss_comp_wssid_hash(&wss->wssid); + wss->tag = wss->hash; + memset(&ie_data, 0, sizeof(ie_data)); + ie_data.wlp_ie.hdr.element_id = UWB_IE_WLP; + ie_data.wlp_ie.hdr.length = sizeof(ie_data) - sizeof(struct uwb_ie_hdr); + wlp_ie_set_hash_length(&ie_data.wlp_ie, sizeof(ie_data.hash)); + ie_data.hash = wss->hash; + result = uwb_rc_ie_add(uwb_rc, &ie_data.wlp_ie.hdr, + sizeof(ie_data)); + if (result < 0) { + dev_err(dev, "WLP: Unable to add WLP IE to beacon. " + "result = %d.\n", result); + goto error_wlp_ie; + } + wss->state = WLP_WSS_STATE_ACTIVE; + result = 0; +error_wlp_ie: + d_fnend(5, dev, "Activating WSS %p, result = %d \n", wss, result); + return result; +} + +/** + * Enroll in and activate WSS identified by provided WSSID + * + * The neighborhood cache should contain a list of all neighbors and the + * WSS they have activated. Based on that cache we search which neighbor we + * can perform the association process with. The user also has option to + * specify which neighbor it prefers as registrar. + * Successful enrollment is followed by activation. + * Successful activation will create the sysfs directory containing + * specific information regarding this WSS. + */ +int wlp_wss_enroll_activate(struct wlp_wss *wss, struct wlp_uuid *wssid, + struct uwb_dev_addr *devaddr) +{ + struct wlp *wlp = container_of(wss, struct wlp, wss); + struct device *dev = &wlp->rc->uwb_dev.dev; + int result = 0; + char buf[WLP_WSS_UUID_STRSIZE]; + + d_fnstart(5, dev, "Enrollment and activation requested. \n"); + mutex_lock(&wss->mutex); + result = wlp_wss_enroll(wss, wssid, devaddr); + if (result < 0) { + wlp_wss_uuid_print(buf, sizeof(buf), &wss->wssid); + dev_err(dev, "WLP: Enrollment into WSS %s failed.\n", buf); + goto error_enroll; + } + result = wlp_wss_activate(wss); + if (result < 0) { + dev_err(dev, "WLP: Unable to activate WSS. Undoing enrollment " + "result = %d \n", result); + /* Undo enrollment */ + wlp_wss_reset(wss); + goto error_activate; + } +error_activate: +error_enroll: + mutex_unlock(&wss->mutex); + d_fnend(5, dev, "Completed. result = %d \n", result); + return result; +} + +/** + * Create, enroll, and activate a new WSS + * + * @wssid: new wssid provided by user + * @name: WSS name requested by used. + * @sec_status: security status requested by user + * + * A user requested the creation of a new WSS. All operations are done + * locally. The new WSS will be stored locally, the hash will be included + * in the WLP IE, and the sysfs infrastructure for this WSS will be + * created. + */ +int wlp_wss_create_activate(struct wlp_wss *wss, struct wlp_uuid *wssid, + char *name, unsigned sec_status, unsigned accept) +{ + struct wlp *wlp = container_of(wss, struct wlp, wss); + struct device *dev = &wlp->rc->uwb_dev.dev; + int result = 0; + char buf[WLP_WSS_UUID_STRSIZE]; + d_fnstart(5, dev, "Request to create new WSS.\n"); + result = wlp_wss_uuid_print(buf, sizeof(buf), wssid); + d_printf(5, dev, "Request to create WSS: WSSID=%s, name=%s, " + "sec_status=%u, accepting enrollment=%u \n", + buf, name, sec_status, accept); + if (!mutex_trylock(&wss->mutex)) { + dev_err(dev, "WLP: WLP association session in progress.\n"); + return -EBUSY; + } + if (wss->state != WLP_WSS_STATE_NONE) { + dev_err(dev, "WLP: WSS already exists. Not creating new.\n"); + result = -EEXIST; + goto out; + } + if (wss->kobj.parent == NULL) { + dev_err(dev, "WLP: WSS parent not ready. Is network interface " + "up?\n"); + result = -ENXIO; + goto out; + } + if (sec_status == WLP_WSS_SECURE) { + dev_err(dev, "WLP: FIXME Creation of secure WSS not " + "supported yet.\n"); + result = -EINVAL; + goto out; + } + wss->wssid = *wssid; + memcpy(wss->name, name, sizeof(wss->name)); + wss->bcast = wlp_wss_sel_bcast_addr(wss); + wss->secure_status = sec_status; + wss->accept_enroll = accept; + /*wss->virtual_addr is initialized in call to wlp_wss_setup*/ + /* sysfs infrastructure */ + result = wlp_wss_sysfs_add(wss, buf); + if (result < 0) { + dev_err(dev, "Cannot set up sysfs for WSS kobject.\n"); + wlp_wss_reset(wss); + goto out; + } else + result = 0; + wss->state = WLP_WSS_STATE_ENROLLED; + result = wlp_wss_activate(wss); + if (result < 0) { + dev_err(dev, "WLP: Unable to activate WSS. Undoing " + "enrollment\n"); + wlp_wss_reset(wss); + goto out; + } + result = 0; +out: + mutex_unlock(&wss->mutex); + d_fnend(5, dev, "Completed. result = %d \n", result); + return result; +} + +/** + * Determine if neighbor has WSS activated + * + * @returns: 1 if neighbor has WSS activated, zero otherwise + * + * This can be done in two ways: + * - send a C1 frame, parse C2/F0 response + * - examine the WLP IE sent by the neighbor + * + * The WLP IE is not fully supported in hardware so we use the C1/C2 frame + * exchange to determine if a WSS is activated. Using the WLP IE should be + * faster and should be used when it becomes possible. + */ +int wlp_wss_is_active(struct wlp *wlp, struct wlp_wss *wss, + struct uwb_dev_addr *dev_addr) +{ + int result = 0; + struct device *dev = &wlp->rc->uwb_dev.dev; + char buf[WLP_WSS_UUID_STRSIZE]; + DECLARE_COMPLETION_ONSTACK(completion); + struct wlp_session session; + struct sk_buff *skb; + struct wlp_frame_assoc *resp; + struct wlp_uuid wssid; + + wlp_wss_uuid_print(buf, sizeof(buf), &wss->wssid); + d_fnstart(5, dev, "wlp %p, wss %p (wssid %s), neighbor %02x:%02x \n", + wlp, wss, buf, dev_addr->data[1], dev_addr->data[0]); + mutex_lock(&wlp->mutex); + /* Send C1 association frame */ + result = wlp_send_assoc_frame(wlp, wss, dev_addr, WLP_ASSOC_C1); + if (result < 0) { + dev_err(dev, "Unable to send C1 frame to neighbor " + "%02x:%02x (%d)\n", dev_addr->data[1], + dev_addr->data[0], result); + result = 0; + goto out; + } + /* Create session, wait for response */ + session.exp_message = WLP_ASSOC_C2; + session.cb = wlp_session_cb; + session.cb_priv = &completion; + session.neighbor_addr = *dev_addr; + BUG_ON(wlp->session != NULL); + wlp->session = &session; + /* Wait for C2/F0 frame */ + result = wait_for_completion_interruptible_timeout(&completion, + WLP_PER_MSG_TIMEOUT * HZ); + if (result == 0) { + dev_err(dev, "Timeout while sending C1 to neighbor " + "%02x:%02x.\n", dev_addr->data[1], + dev_addr->data[0]); + goto out; + } + if (result < 0) { + dev_err(dev, "Unable to send C1 to neighbor %02x:%02x.\n", + dev_addr->data[1], dev_addr->data[0]); + result = 0; + goto out; + } + /* Parse message in session->data: it will be either C2 or F0 */ + skb = session.data; + resp = (void *) skb->data; + d_printf(5, dev, "Received response to C1 frame. \n"); + d_dump(5, dev, skb->data, skb->len > 72 ? 72 : skb->len); + if (resp->type == WLP_ASSOC_F0) { + result = wlp_parse_f0(wlp, skb); + if (result < 0) + dev_err(dev, "WLP: unable to parse incoming F0 " + "frame from neighbor %02x:%02x.\n", + dev_addr->data[1], dev_addr->data[0]); + result = 0; + goto error_resp_parse; + } + /* WLP version and message type fields have already been parsed */ + result = wlp_get_wssid(wlp, (void *)resp + sizeof(*resp), &wssid, + skb->len - sizeof(*resp)); + if (result < 0) { + dev_err(dev, "WLP: unable to obtain WSSID from C2 frame.\n"); + result = 0; + goto error_resp_parse; + } + if (!memcmp(&wssid, &wss->wssid, sizeof(wssid))) { + d_printf(5, dev, "WSSID in C2 frame matches local " + "active WSS.\n"); + result = 1; + } else { + dev_err(dev, "WLP: Received a C2 frame without matching " + "WSSID.\n"); + result = 0; + } +error_resp_parse: + kfree_skb(skb); +out: + wlp->session = NULL; + mutex_unlock(&wlp->mutex); + d_fnend(5, dev, "wlp %p, wss %p (wssid %s), neighbor %02x:%02x \n", + wlp, wss, buf, dev_addr->data[1], dev_addr->data[0]); + return result; +} + +/** + * Activate connection with neighbor by updating EDA cache + * + * @wss: local WSS to which neighbor wants to connect + * @dev_addr: neighbor's address + * @wssid: neighbor's WSSID - must be same as our WSS's WSSID + * @tag: neighbor's WSS tag used to identify frames transmitted by it + * @virt_addr: neighbor's virtual EUI-48 + */ +static +int wlp_wss_activate_connection(struct wlp *wlp, struct wlp_wss *wss, + struct uwb_dev_addr *dev_addr, + struct wlp_uuid *wssid, u8 *tag, + struct uwb_mac_addr *virt_addr) +{ + struct device *dev = &wlp->rc->uwb_dev.dev; + int result = 0; + char buf[WLP_WSS_UUID_STRSIZE]; + wlp_wss_uuid_print(buf, sizeof(buf), wssid); + d_fnstart(5, dev, "wlp %p, wss %p, wssid %s, tag %u, virtual " + "%02x:%02x:%02x:%02x:%02x:%02x \n", wlp, wss, buf, *tag, + virt_addr->data[0], virt_addr->data[1], virt_addr->data[2], + virt_addr->data[3], virt_addr->data[4], virt_addr->data[5]); + + if (!memcmp(wssid, &wss->wssid, sizeof(*wssid))) { + d_printf(5, dev, "WSSID from neighbor frame matches local " + "active WSS.\n"); + /* Update EDA cache */ + result = wlp_eda_update_node(&wlp->eda, dev_addr, wss, + (void *) virt_addr->data, *tag, + WLP_WSS_CONNECTED); + if (result < 0) + dev_err(dev, "WLP: Unable to update EDA cache " + "with new connected neighbor information.\n"); + } else { + dev_err(dev, "WLP: Neighbor does not have matching " + "WSSID.\n"); + result = -EINVAL; + } + + d_fnend(5, dev, "wlp %p, wss %p, wssid %s, tag %u, virtual " + "%02x:%02x:%02x:%02x:%02x:%02x, result = %d \n", + wlp, wss, buf, *tag, + virt_addr->data[0], virt_addr->data[1], virt_addr->data[2], + virt_addr->data[3], virt_addr->data[4], virt_addr->data[5], + result); + + return result; +} + +/** + * Connect to WSS neighbor + * + * Use C3/C4 exchange to determine if neighbor has WSS activated and + * retrieve the WSS tag and virtual EUI-48 of the neighbor. + */ +static +int wlp_wss_connect_neighbor(struct wlp *wlp, struct wlp_wss *wss, + struct uwb_dev_addr *dev_addr) +{ + int result; + struct device *dev = &wlp->rc->uwb_dev.dev; + char buf[WLP_WSS_UUID_STRSIZE]; + struct wlp_uuid wssid; + u8 tag; + struct uwb_mac_addr virt_addr; + DECLARE_COMPLETION_ONSTACK(completion); + struct wlp_session session; + struct wlp_frame_assoc *resp; + struct sk_buff *skb; + + wlp_wss_uuid_print(buf, sizeof(buf), &wss->wssid); + d_fnstart(5, dev, "wlp %p, wss %p (wssid %s), neighbor %02x:%02x \n", + wlp, wss, buf, dev_addr->data[1], dev_addr->data[0]); + mutex_lock(&wlp->mutex); + /* Send C3 association frame */ + result = wlp_send_assoc_frame(wlp, wss, dev_addr, WLP_ASSOC_C3); + if (result < 0) { + dev_err(dev, "Unable to send C3 frame to neighbor " + "%02x:%02x (%d)\n", dev_addr->data[1], + dev_addr->data[0], result); + goto out; + } + /* Create session, wait for response */ + session.exp_message = WLP_ASSOC_C4; + session.cb = wlp_session_cb; + session.cb_priv = &completion; + session.neighbor_addr = *dev_addr; + BUG_ON(wlp->session != NULL); + wlp->session = &session; + /* Wait for C4/F0 frame */ + result = wait_for_completion_interruptible_timeout(&completion, + WLP_PER_MSG_TIMEOUT * HZ); + if (result == 0) { + dev_err(dev, "Timeout while sending C3 to neighbor " + "%02x:%02x.\n", dev_addr->data[1], + dev_addr->data[0]); + result = -ETIMEDOUT; + goto out; + } + if (result < 0) { + dev_err(dev, "Unable to send C3 to neighbor %02x:%02x.\n", + dev_addr->data[1], dev_addr->data[0]); + goto out; + } + /* Parse message in session->data: it will be either C4 or F0 */ + skb = session.data; + resp = (void *) skb->data; + d_printf(5, dev, "Received response to C3 frame. \n"); + d_dump(5, dev, skb->data, skb->len > 72 ? 72 : skb->len); + if (resp->type == WLP_ASSOC_F0) { + result = wlp_parse_f0(wlp, skb); + if (result < 0) + dev_err(dev, "WLP: unable to parse incoming F0 " + "frame from neighbor %02x:%02x.\n", + dev_addr->data[1], dev_addr->data[0]); + result = -EINVAL; + goto error_resp_parse; + } + result = wlp_parse_c3c4_frame(wlp, skb, &wssid, &tag, &virt_addr); + if (result < 0) { + dev_err(dev, "WLP: Unable to parse C4 frame from neighbor.\n"); + goto error_resp_parse; + } + result = wlp_wss_activate_connection(wlp, wss, dev_addr, &wssid, &tag, + &virt_addr); + if (result < 0) { + dev_err(dev, "WLP: Unable to activate connection to " + "neighbor %02x:%02x.\n", dev_addr->data[1], + dev_addr->data[0]); + goto error_resp_parse; + } +error_resp_parse: + kfree_skb(skb); +out: + /* Record that we unsuccessfully tried to connect to this neighbor */ + if (result < 0) + wlp_eda_update_node_state(&wlp->eda, dev_addr, + WLP_WSS_CONNECT_FAILED); + wlp->session = NULL; + mutex_unlock(&wlp->mutex); + d_fnend(5, dev, "wlp %p, wss %p (wssid %s), neighbor %02x:%02x \n", + wlp, wss, buf, dev_addr->data[1], dev_addr->data[0]); + return result; +} + +/** + * Connect to neighbor with common WSS, send pending frame + * + * This function is scheduled when a frame is destined to a neighbor with + * which we do not have a connection. A copy of the EDA cache entry is + * provided - not the actual cache entry (because it is protected by a + * spinlock). + * + * First determine if neighbor has the same WSS activated, connect if it + * does. The C3/C4 exchange is dual purpose to determine if neighbor has + * WSS activated and proceed with the connection. + * + * The frame that triggered the connection setup is sent after connection + * setup. + * + * network queue is stopped - we need to restart when done + * + */ +static +void wlp_wss_connect_send(struct work_struct *ws) +{ + struct wlp_assoc_conn_ctx *conn_ctx = container_of(ws, + struct wlp_assoc_conn_ctx, + ws); + struct wlp *wlp = conn_ctx->wlp; + struct sk_buff *skb = conn_ctx->skb; + struct wlp_eda_node *eda_entry = &conn_ctx->eda_entry; + struct uwb_dev_addr *dev_addr = &eda_entry->dev_addr; + struct wlp_wss *wss = &wlp->wss; + int result; + struct device *dev = &wlp->rc->uwb_dev.dev; + char buf[WLP_WSS_UUID_STRSIZE]; + + mutex_lock(&wss->mutex); + wlp_wss_uuid_print(buf, sizeof(buf), &wss->wssid); + d_fnstart(5, dev, "wlp %p, wss %p (wssid %s), neighbor %02x:%02x \n", + wlp, wss, buf, dev_addr->data[1], dev_addr->data[0]); + if (wss->state < WLP_WSS_STATE_ACTIVE) { + if (printk_ratelimit()) + dev_err(dev, "WLP: Attempting to connect with " + "WSS that is not active or connected.\n"); + dev_kfree_skb(skb); + goto out; + } + /* Establish connection - send C3 rcv C4 */ + result = wlp_wss_connect_neighbor(wlp, wss, dev_addr); + if (result < 0) { + if (printk_ratelimit()) + dev_err(dev, "WLP: Unable to establish connection " + "with neighbor %02x:%02x.\n", + dev_addr->data[1], dev_addr->data[0]); + dev_kfree_skb(skb); + goto out; + } + /* EDA entry changed, update the local copy being used */ + result = wlp_copy_eda_node(&wlp->eda, dev_addr, eda_entry); + if (result < 0) { + if (printk_ratelimit()) + dev_err(dev, "WLP: Cannot find EDA entry for " + "neighbor %02x:%02x \n", + dev_addr->data[1], dev_addr->data[0]); + } + result = wlp_wss_prep_hdr(wlp, eda_entry, skb); + if (result < 0) { + if (printk_ratelimit()) + dev_err(dev, "WLP: Unable to prepare frame header for " + "transmission (neighbor %02x:%02x). \n", + dev_addr->data[1], dev_addr->data[0]); + dev_kfree_skb(skb); + goto out; + } + BUG_ON(wlp->xmit_frame == NULL); + result = wlp->xmit_frame(wlp, skb, dev_addr); + if (result < 0) { + if (printk_ratelimit()) + dev_err(dev, "WLP: Unable to transmit frame: %d\n", + result); + if (result == -ENXIO) + dev_err(dev, "WLP: Is network interface up? \n"); + /* We could try again ... */ + dev_kfree_skb(skb);/*we need to free if tx fails */ + } +out: + kfree(conn_ctx); + BUG_ON(wlp->start_queue == NULL); + wlp->start_queue(wlp); + mutex_unlock(&wss->mutex); + d_fnend(5, dev, "wlp %p, wss %p (wssid %s)\n", wlp, wss, buf); +} + +/** + * Add WLP header to outgoing skb + * + * @eda_entry: pointer to neighbor's entry in the EDA cache + * @_skb: skb containing data destined to the neighbor + */ +int wlp_wss_prep_hdr(struct wlp *wlp, struct wlp_eda_node *eda_entry, + void *_skb) +{ + struct device *dev = &wlp->rc->uwb_dev.dev; + int result = 0; + unsigned char *eth_addr = eda_entry->eth_addr; + struct uwb_dev_addr *dev_addr = &eda_entry->dev_addr; + struct sk_buff *skb = _skb; + struct wlp_frame_std_abbrv_hdr *std_hdr; + + d_fnstart(6, dev, "wlp %p \n", wlp); + if (eda_entry->state == WLP_WSS_CONNECTED) { + /* Add WLP header */ + BUG_ON(skb_headroom(skb) < sizeof(*std_hdr)); + std_hdr = (void *) __skb_push(skb, sizeof(*std_hdr)); + std_hdr->hdr.mux_hdr = cpu_to_le16(WLP_PROTOCOL_ID); + std_hdr->hdr.type = WLP_FRAME_STANDARD; + std_hdr->tag = eda_entry->wss->tag; + } else { + if (printk_ratelimit()) + dev_err(dev, "WLP: Destination neighbor (Ethernet: " + "%02x:%02x:%02x:%02x:%02x:%02x, Dev: " + "%02x:%02x) is not connected. \n", eth_addr[0], + eth_addr[1], eth_addr[2], eth_addr[3], + eth_addr[4], eth_addr[5], dev_addr->data[1], + dev_addr->data[0]); + result = -EINVAL; + } + d_fnend(6, dev, "wlp %p \n", wlp); + return result; +} + + +/** + * Prepare skb for neighbor: connect if not already and prep WLP header + * + * This function is called in interrupt context, but it needs to sleep. We + * temporarily stop the net queue to establish the WLP connection. + * Setup of the WLP connection and restart of queue is scheduled + * on the default work queue. + * + * run with eda->lock held (spinlock) + */ +int wlp_wss_connect_prep(struct wlp *wlp, struct wlp_eda_node *eda_entry, + void *_skb) +{ + int result = 0; + struct device *dev = &wlp->rc->uwb_dev.dev; + struct uwb_dev_addr *dev_addr = &eda_entry->dev_addr; + unsigned char *eth_addr = eda_entry->eth_addr; + struct sk_buff *skb = _skb; + struct wlp_assoc_conn_ctx *conn_ctx; + + d_fnstart(5, dev, "wlp %p\n", wlp); + d_printf(5, dev, "To neighbor %02x:%02x with eth " + "%02x:%02x:%02x:%02x:%02x:%02x\n", dev_addr->data[1], + dev_addr->data[0], eth_addr[0], eth_addr[1], eth_addr[2], + eth_addr[3], eth_addr[4], eth_addr[5]); + if (eda_entry->state == WLP_WSS_UNCONNECTED) { + /* We don't want any more packets while we set up connection */ + BUG_ON(wlp->stop_queue == NULL); + wlp->stop_queue(wlp); + conn_ctx = kmalloc(sizeof(*conn_ctx), GFP_ATOMIC); + if (conn_ctx == NULL) { + if (printk_ratelimit()) + dev_err(dev, "WLP: Unable to allocate memory " + "for connection handling.\n"); + result = -ENOMEM; + goto out; + } + conn_ctx->wlp = wlp; + conn_ctx->skb = skb; + conn_ctx->eda_entry = *eda_entry; + INIT_WORK(&conn_ctx->ws, wlp_wss_connect_send); + schedule_work(&conn_ctx->ws); + result = 1; + } else if (eda_entry->state == WLP_WSS_CONNECT_FAILED) { + /* Previous connection attempts failed, don't retry - see + * conditions for connection in WLP 0.99 [7.6.2] */ + if (printk_ratelimit()) + dev_err(dev, "Could not connect to neighbor " + "previously. Not retrying. \n"); + result = -ENONET; + goto out; + } else { /* eda_entry->state == WLP_WSS_CONNECTED */ + d_printf(5, dev, "Neighbor is connected, preparing frame.\n"); + result = wlp_wss_prep_hdr(wlp, eda_entry, skb); + } +out: + d_fnend(5, dev, "wlp %p, result = %d \n", wlp, result); + return result; +} + +/** + * Emulate broadcast: copy skb, send copy to neighbor (connect if not already) + * + * We need to copy skbs in the case where we emulate broadcast through + * unicast. We copy instead of clone because we are modifying the data of + * the frame after copying ... clones share data so we cannot emulate + * broadcast using clones. + * + * run with eda->lock held (spinlock) + */ +int wlp_wss_send_copy(struct wlp *wlp, struct wlp_eda_node *eda_entry, + void *_skb) +{ + int result = -ENOMEM; + struct device *dev = &wlp->rc->uwb_dev.dev; + struct sk_buff *skb = _skb; + struct sk_buff *copy; + struct uwb_dev_addr *dev_addr = &eda_entry->dev_addr; + + d_fnstart(5, dev, "to neighbor %02x:%02x, skb (%p) \n", + dev_addr->data[1], dev_addr->data[0], skb); + copy = skb_copy(skb, GFP_ATOMIC); + if (copy == NULL) { + if (printk_ratelimit()) + dev_err(dev, "WLP: Unable to copy skb for " + "transmission.\n"); + goto out; + } + result = wlp_wss_connect_prep(wlp, eda_entry, copy); + if (result < 0) { + if (printk_ratelimit()) + dev_err(dev, "WLP: Unable to connect/send skb " + "to neighbor.\n"); + dev_kfree_skb_irq(copy); + goto out; + } else if (result == 1) + /* Frame will be transmitted separately */ + goto out; + BUG_ON(wlp->xmit_frame == NULL); + result = wlp->xmit_frame(wlp, copy, dev_addr); + if (result < 0) { + if (printk_ratelimit()) + dev_err(dev, "WLP: Unable to transmit frame: %d\n", + result); + if ((result == -ENXIO) && printk_ratelimit()) + dev_err(dev, "WLP: Is network interface up? \n"); + /* We could try again ... */ + dev_kfree_skb_irq(copy);/*we need to free if tx fails */ + } +out: + d_fnend(5, dev, "to neighbor %02x:%02x \n", dev_addr->data[1], + dev_addr->data[0]); + return result; +} + + +/** + * Setup WSS + * + * Should be called by network driver after the interface has been given a + * MAC address. + */ +int wlp_wss_setup(struct net_device *net_dev, struct wlp_wss *wss) +{ + struct wlp *wlp = container_of(wss, struct wlp, wss); + struct device *dev = &wlp->rc->uwb_dev.dev; + int result = 0; + d_fnstart(5, dev, "wss (%p) \n", wss); + mutex_lock(&wss->mutex); + wss->kobj.parent = &net_dev->dev.kobj; + if (!is_valid_ether_addr(net_dev->dev_addr)) { + dev_err(dev, "WLP: Invalid MAC address. Cannot use for" + "virtual.\n"); + result = -EINVAL; + goto out; + } + memcpy(wss->virtual_addr.data, net_dev->dev_addr, + sizeof(wss->virtual_addr.data)); +out: + mutex_unlock(&wss->mutex); + d_fnend(5, dev, "wss (%p) \n", wss); + return result; +} +EXPORT_SYMBOL_GPL(wlp_wss_setup); + +/** + * Remove WSS + * + * Called by client that configured WSS through wlp_wss_setup(). This + * function is called when client no longer needs WSS, eg. client shuts + * down. + * + * We remove the WLP IE from the beacon before initiating local cleanup. + */ +void wlp_wss_remove(struct wlp_wss *wss) +{ + struct wlp *wlp = container_of(wss, struct wlp, wss); + struct device *dev = &wlp->rc->uwb_dev.dev; + d_fnstart(5, dev, "wss (%p) \n", wss); + mutex_lock(&wss->mutex); + if (wss->state == WLP_WSS_STATE_ACTIVE) + uwb_rc_ie_rm(wlp->rc, UWB_IE_WLP); + if (wss->state != WLP_WSS_STATE_NONE) { + sysfs_remove_group(&wss->kobj, &wss_attr_group); + kobject_put(&wss->kobj); + } + wss->kobj.parent = NULL; + memset(&wss->virtual_addr, 0, sizeof(wss->virtual_addr)); + /* Cleanup EDA cache */ + wlp_eda_release(&wlp->eda); + wlp_eda_init(&wlp->eda); + mutex_unlock(&wss->mutex); + d_fnend(5, dev, "wss (%p) \n", wss); +} +EXPORT_SYMBOL_GPL(wlp_wss_remove); |