diff options
Diffstat (limited to 'drivers/usb/wusbcore/security.c')
-rw-r--r-- | drivers/usb/wusbcore/security.c | 599 |
1 files changed, 0 insertions, 599 deletions
diff --git a/drivers/usb/wusbcore/security.c b/drivers/usb/wusbcore/security.c deleted file mode 100644 index 14ac8c98ac9e..000000000000 --- a/drivers/usb/wusbcore/security.c +++ /dev/null @@ -1,599 +0,0 @@ -// SPDX-License-Identifier: GPL-2.0 -/* - * Wireless USB Host Controller - * Security support: encryption enablement, etc - * - * Copyright (C) 2006 Intel Corporation - * Inaky Perez-Gonzalez <inaky.perez-gonzalez@intel.com> - * - * FIXME: docs - */ -#include <linux/types.h> -#include <linux/slab.h> -#include <linux/usb/ch9.h> -#include <linux/random.h> -#include <linux/export.h> -#include "wusbhc.h" -#include <asm/unaligned.h> - -static void wusbhc_gtk_rekey_work(struct work_struct *work); - -int wusbhc_sec_create(struct wusbhc *wusbhc) -{ - /* - * WQ is singlethread because we need to serialize rekey operations. - * Use a separate workqueue for security operations instead of the - * wusbd workqueue because security operations may need to communicate - * directly with downstream wireless devices using synchronous URBs. - * If a device is not responding, this could block other host - * controller operations. - */ - wusbhc->wq_security = create_singlethread_workqueue("wusbd_security"); - if (wusbhc->wq_security == NULL) { - pr_err("WUSB-core: Cannot create wusbd_security workqueue\n"); - return -ENOMEM; - } - - wusbhc->gtk.descr.bLength = sizeof(wusbhc->gtk.descr) + - sizeof(wusbhc->gtk.data); - wusbhc->gtk.descr.bDescriptorType = USB_DT_KEY; - wusbhc->gtk.descr.bReserved = 0; - wusbhc->gtk_index = 0; - - INIT_WORK(&wusbhc->gtk_rekey_work, wusbhc_gtk_rekey_work); - - return 0; -} - - -/* Called when the HC is destroyed */ -void wusbhc_sec_destroy(struct wusbhc *wusbhc) -{ - destroy_workqueue(wusbhc->wq_security); -} - - -/** - * wusbhc_next_tkid - generate a new, currently unused, TKID - * @wusbhc: the WUSB host controller - * @wusb_dev: the device whose PTK the TKID is for - * (or NULL for a TKID for a GTK) - * - * The generated TKID consists of two parts: the device's authenticated - * address (or 0 or a GTK); and an incrementing number. This ensures - * that TKIDs cannot be shared between devices and by the time the - * incrementing number wraps around the older TKIDs will no longer be - * in use (a maximum of two keys may be active at any one time). - */ -static u32 wusbhc_next_tkid(struct wusbhc *wusbhc, struct wusb_dev *wusb_dev) -{ - u32 *tkid; - u32 addr; - - if (wusb_dev == NULL) { - tkid = &wusbhc->gtk_tkid; - addr = 0; - } else { - tkid = &wusb_port_by_idx(wusbhc, wusb_dev->port_idx)->ptk_tkid; - addr = wusb_dev->addr & 0x7f; - } - - *tkid = (addr << 8) | ((*tkid + 1) & 0xff); - - return *tkid; -} - -static void wusbhc_generate_gtk(struct wusbhc *wusbhc) -{ - const size_t key_size = sizeof(wusbhc->gtk.data); - u32 tkid; - - tkid = wusbhc_next_tkid(wusbhc, NULL); - - wusbhc->gtk.descr.tTKID[0] = (tkid >> 0) & 0xff; - wusbhc->gtk.descr.tTKID[1] = (tkid >> 8) & 0xff; - wusbhc->gtk.descr.tTKID[2] = (tkid >> 16) & 0xff; - - get_random_bytes(wusbhc->gtk.descr.bKeyData, key_size); -} - -/** - * wusbhc_sec_start - start the security management process - * @wusbhc: the WUSB host controller - * - * Generate and set an initial GTK on the host controller. - * - * Called when the HC is started. - */ -int wusbhc_sec_start(struct wusbhc *wusbhc) -{ - const size_t key_size = sizeof(wusbhc->gtk.data); - int result; - - wusbhc_generate_gtk(wusbhc); - - result = wusbhc->set_gtk(wusbhc, wusbhc->gtk_tkid, - &wusbhc->gtk.descr.bKeyData, key_size); - if (result < 0) - dev_err(wusbhc->dev, "cannot set GTK for the host: %d\n", - result); - - return result; -} - -/** - * wusbhc_sec_stop - stop the security management process - * @wusbhc: the WUSB host controller - * - * Wait for any pending GTK rekeys to stop. - */ -void wusbhc_sec_stop(struct wusbhc *wusbhc) -{ - cancel_work_sync(&wusbhc->gtk_rekey_work); -} - - -/** @returns encryption type name */ -const char *wusb_et_name(u8 x) -{ - switch (x) { - case USB_ENC_TYPE_UNSECURE: return "unsecure"; - case USB_ENC_TYPE_WIRED: return "wired"; - case USB_ENC_TYPE_CCM_1: return "CCM-1"; - case USB_ENC_TYPE_RSA_1: return "RSA-1"; - default: return "unknown"; - } -} -EXPORT_SYMBOL_GPL(wusb_et_name); - -/* - * Set the device encryption method - * - * We tell the device which encryption method to use; we do this when - * setting up the device's security. - */ -static int wusb_dev_set_encryption(struct usb_device *usb_dev, int value) -{ - int result; - struct device *dev = &usb_dev->dev; - struct wusb_dev *wusb_dev = usb_dev->wusb_dev; - - if (value) { - value = wusb_dev->ccm1_etd.bEncryptionValue; - } else { - /* FIXME: should be wusb_dev->etd[UNSECURE].bEncryptionValue */ - value = 0; - } - /* Set device's */ - result = usb_control_msg(usb_dev, usb_sndctrlpipe(usb_dev, 0), - USB_REQ_SET_ENCRYPTION, - USB_DIR_OUT | USB_TYPE_STANDARD | USB_RECIP_DEVICE, - value, 0, NULL, 0, USB_CTRL_SET_TIMEOUT); - if (result < 0) - dev_err(dev, "Can't set device's WUSB encryption to " - "%s (value %d): %d\n", - wusb_et_name(wusb_dev->ccm1_etd.bEncryptionType), - wusb_dev->ccm1_etd.bEncryptionValue, result); - return result; -} - -/* - * Set the GTK to be used by a device. - * - * The device must be authenticated. - */ -static int wusb_dev_set_gtk(struct wusbhc *wusbhc, struct wusb_dev *wusb_dev) -{ - struct usb_device *usb_dev = wusb_dev->usb_dev; - u8 key_index = wusb_key_index(wusbhc->gtk_index, - WUSB_KEY_INDEX_TYPE_GTK, WUSB_KEY_INDEX_ORIGINATOR_HOST); - - return usb_control_msg( - usb_dev, usb_sndctrlpipe(usb_dev, 0), - USB_REQ_SET_DESCRIPTOR, - USB_DIR_OUT | USB_TYPE_STANDARD | USB_RECIP_DEVICE, - USB_DT_KEY << 8 | key_index, 0, - &wusbhc->gtk.descr, wusbhc->gtk.descr.bLength, - USB_CTRL_SET_TIMEOUT); -} - - -/* FIXME: prototype for adding security */ -int wusb_dev_sec_add(struct wusbhc *wusbhc, - struct usb_device *usb_dev, struct wusb_dev *wusb_dev) -{ - int result, bytes, secd_size; - struct device *dev = &usb_dev->dev; - struct usb_security_descriptor *secd, *new_secd; - const struct usb_encryption_descriptor *etd, *ccm1_etd = NULL; - const void *itr, *top; - char buf[64]; - - secd = kmalloc(sizeof(*secd), GFP_KERNEL); - if (secd == NULL) { - result = -ENOMEM; - goto out; - } - - result = usb_get_descriptor(usb_dev, USB_DT_SECURITY, - 0, secd, sizeof(*secd)); - if (result < (int)sizeof(*secd)) { - dev_err(dev, "Can't read security descriptor or " - "not enough data: %d\n", result); - goto out; - } - secd_size = le16_to_cpu(secd->wTotalLength); - new_secd = krealloc(secd, secd_size, GFP_KERNEL); - if (new_secd == NULL) { - dev_err(dev, - "Can't allocate space for security descriptors\n"); - result = -ENOMEM; - goto out; - } - secd = new_secd; - result = usb_get_descriptor(usb_dev, USB_DT_SECURITY, - 0, secd, secd_size); - if (result < secd_size) { - dev_err(dev, "Can't read security descriptor or " - "not enough data: %d\n", result); - goto out; - } - bytes = 0; - itr = &secd[1]; - top = (void *)secd + result; - while (itr < top) { - etd = itr; - if (top - itr < sizeof(*etd)) { - dev_err(dev, "BUG: bad device security descriptor; " - "not enough data (%zu vs %zu bytes left)\n", - top - itr, sizeof(*etd)); - break; - } - if (etd->bLength < sizeof(*etd)) { - dev_err(dev, "BUG: bad device encryption descriptor; " - "descriptor is too short " - "(%u vs %zu needed)\n", - etd->bLength, sizeof(*etd)); - break; - } - itr += etd->bLength; - bytes += snprintf(buf + bytes, sizeof(buf) - bytes, - "%s (0x%02x/%02x) ", - wusb_et_name(etd->bEncryptionType), - etd->bEncryptionValue, etd->bAuthKeyIndex); - if (etd->bEncryptionType == USB_ENC_TYPE_CCM_1) - ccm1_etd = etd; - } - /* This code only supports CCM1 as of now. */ - /* FIXME: user has to choose which sec mode to use? - * In theory we want CCM */ - if (ccm1_etd == NULL) { - dev_err(dev, "WUSB device doesn't support CCM1 encryption, " - "can't use!\n"); - result = -EINVAL; - goto out; - } - wusb_dev->ccm1_etd = *ccm1_etd; - dev_dbg(dev, "supported encryption: %s; using %s (0x%02x/%02x)\n", - buf, wusb_et_name(ccm1_etd->bEncryptionType), - ccm1_etd->bEncryptionValue, ccm1_etd->bAuthKeyIndex); - result = 0; -out: - kfree(secd); - return result; -} - -void wusb_dev_sec_rm(struct wusb_dev *wusb_dev) -{ - /* Nothing so far */ -} - -/** - * Update the address of an unauthenticated WUSB device - * - * Once we have successfully authenticated, we take it to addr0 state - * and then to a normal address. - * - * Before the device's address (as known by it) was usb_dev->devnum | - * 0x80 (unauthenticated address). With this we update it to usb_dev->devnum. - */ -int wusb_dev_update_address(struct wusbhc *wusbhc, struct wusb_dev *wusb_dev) -{ - int result = -ENOMEM; - struct usb_device *usb_dev = wusb_dev->usb_dev; - struct device *dev = &usb_dev->dev; - u8 new_address = wusb_dev->addr & 0x7F; - - /* Set address 0 */ - result = usb_control_msg(usb_dev, usb_sndctrlpipe(usb_dev, 0), - USB_REQ_SET_ADDRESS, - USB_DIR_OUT | USB_TYPE_STANDARD | USB_RECIP_DEVICE, - 0, 0, NULL, 0, USB_CTRL_SET_TIMEOUT); - if (result < 0) { - dev_err(dev, "auth failed: can't set address 0: %d\n", - result); - goto error_addr0; - } - result = wusb_set_dev_addr(wusbhc, wusb_dev, 0); - if (result < 0) - goto error_addr0; - usb_set_device_state(usb_dev, USB_STATE_DEFAULT); - usb_ep0_reinit(usb_dev); - - /* Set new (authenticated) address. */ - result = usb_control_msg(usb_dev, usb_sndctrlpipe(usb_dev, 0), - USB_REQ_SET_ADDRESS, - USB_DIR_OUT | USB_TYPE_STANDARD | USB_RECIP_DEVICE, - new_address, 0, NULL, 0, - USB_CTRL_SET_TIMEOUT); - if (result < 0) { - dev_err(dev, "auth failed: can't set address %u: %d\n", - new_address, result); - goto error_addr; - } - result = wusb_set_dev_addr(wusbhc, wusb_dev, new_address); - if (result < 0) - goto error_addr; - usb_set_device_state(usb_dev, USB_STATE_ADDRESS); - usb_ep0_reinit(usb_dev); - usb_dev->authenticated = 1; -error_addr: -error_addr0: - return result; -} - -/* - * - * - */ -/* FIXME: split and cleanup */ -int wusb_dev_4way_handshake(struct wusbhc *wusbhc, struct wusb_dev *wusb_dev, - struct wusb_ckhdid *ck) -{ - int result = -ENOMEM; - struct usb_device *usb_dev = wusb_dev->usb_dev; - struct device *dev = &usb_dev->dev; - u32 tkid; - struct usb_handshake *hs; - struct aes_ccm_nonce ccm_n; - u8 mic[8]; - struct wusb_keydvt_in keydvt_in; - struct wusb_keydvt_out keydvt_out; - - hs = kcalloc(3, sizeof(hs[0]), GFP_KERNEL); - if (!hs) - goto error_kzalloc; - - /* We need to turn encryption before beginning the 4way - * hshake (WUSB1.0[.3.2.2]) */ - result = wusb_dev_set_encryption(usb_dev, 1); - if (result < 0) - goto error_dev_set_encryption; - - tkid = wusbhc_next_tkid(wusbhc, wusb_dev); - - hs[0].bMessageNumber = 1; - hs[0].bStatus = 0; - put_unaligned_le32(tkid, hs[0].tTKID); - hs[0].bReserved = 0; - memcpy(hs[0].CDID, &wusb_dev->cdid, sizeof(hs[0].CDID)); - get_random_bytes(&hs[0].nonce, sizeof(hs[0].nonce)); - memset(hs[0].MIC, 0, sizeof(hs[0].MIC)); /* Per WUSB1.0[T7-22] */ - - result = usb_control_msg( - usb_dev, usb_sndctrlpipe(usb_dev, 0), - USB_REQ_SET_HANDSHAKE, - USB_DIR_OUT | USB_TYPE_STANDARD | USB_RECIP_DEVICE, - 1, 0, &hs[0], sizeof(hs[0]), USB_CTRL_SET_TIMEOUT); - if (result < 0) { - dev_err(dev, "Handshake1: request failed: %d\n", result); - goto error_hs1; - } - - /* Handshake 2, from the device -- need to verify fields */ - result = usb_control_msg( - usb_dev, usb_rcvctrlpipe(usb_dev, 0), - USB_REQ_GET_HANDSHAKE, - USB_DIR_IN | USB_TYPE_STANDARD | USB_RECIP_DEVICE, - 2, 0, &hs[1], sizeof(hs[1]), USB_CTRL_GET_TIMEOUT); - if (result < 0) { - dev_err(dev, "Handshake2: request failed: %d\n", result); - goto error_hs2; - } - - result = -EINVAL; - if (hs[1].bMessageNumber != 2) { - dev_err(dev, "Handshake2 failed: bad message number %u\n", - hs[1].bMessageNumber); - goto error_hs2; - } - if (hs[1].bStatus != 0) { - dev_err(dev, "Handshake2 failed: bad status %u\n", - hs[1].bStatus); - goto error_hs2; - } - if (memcmp(hs[0].tTKID, hs[1].tTKID, sizeof(hs[0].tTKID))) { - dev_err(dev, "Handshake2 failed: TKID mismatch " - "(#1 0x%02x%02x%02x vs #2 0x%02x%02x%02x)\n", - hs[0].tTKID[0], hs[0].tTKID[1], hs[0].tTKID[2], - hs[1].tTKID[0], hs[1].tTKID[1], hs[1].tTKID[2]); - goto error_hs2; - } - if (memcmp(hs[0].CDID, hs[1].CDID, sizeof(hs[0].CDID))) { - dev_err(dev, "Handshake2 failed: CDID mismatch\n"); - goto error_hs2; - } - - /* Setup the CCM nonce */ - memset(&ccm_n.sfn, 0, sizeof(ccm_n.sfn)); /* Per WUSB1.0[6.5.2] */ - put_unaligned_le32(tkid, ccm_n.tkid); - ccm_n.src_addr = wusbhc->uwb_rc->uwb_dev.dev_addr; - ccm_n.dest_addr.data[0] = wusb_dev->addr; - ccm_n.dest_addr.data[1] = 0; - - /* Derive the KCK and PTK from CK, the CCM, H and D nonces */ - memcpy(keydvt_in.hnonce, hs[0].nonce, sizeof(keydvt_in.hnonce)); - memcpy(keydvt_in.dnonce, hs[1].nonce, sizeof(keydvt_in.dnonce)); - result = wusb_key_derive(&keydvt_out, ck->data, &ccm_n, &keydvt_in); - if (result < 0) { - dev_err(dev, "Handshake2 failed: cannot derive keys: %d\n", - result); - goto error_hs2; - } - - /* Compute MIC and verify it */ - result = wusb_oob_mic(mic, keydvt_out.kck, &ccm_n, &hs[1]); - if (result < 0) { - dev_err(dev, "Handshake2 failed: cannot compute MIC: %d\n", - result); - goto error_hs2; - } - - if (memcmp(hs[1].MIC, mic, sizeof(hs[1].MIC))) { - dev_err(dev, "Handshake2 failed: MIC mismatch\n"); - goto error_hs2; - } - - /* Send Handshake3 */ - hs[2].bMessageNumber = 3; - hs[2].bStatus = 0; - put_unaligned_le32(tkid, hs[2].tTKID); - hs[2].bReserved = 0; - memcpy(hs[2].CDID, &wusb_dev->cdid, sizeof(hs[2].CDID)); - memcpy(hs[2].nonce, hs[0].nonce, sizeof(hs[2].nonce)); - result = wusb_oob_mic(hs[2].MIC, keydvt_out.kck, &ccm_n, &hs[2]); - if (result < 0) { - dev_err(dev, "Handshake3 failed: cannot compute MIC: %d\n", - result); - goto error_hs2; - } - - result = usb_control_msg( - usb_dev, usb_sndctrlpipe(usb_dev, 0), - USB_REQ_SET_HANDSHAKE, - USB_DIR_OUT | USB_TYPE_STANDARD | USB_RECIP_DEVICE, - 3, 0, &hs[2], sizeof(hs[2]), USB_CTRL_SET_TIMEOUT); - if (result < 0) { - dev_err(dev, "Handshake3: request failed: %d\n", result); - goto error_hs3; - } - - result = wusbhc->set_ptk(wusbhc, wusb_dev->port_idx, tkid, - keydvt_out.ptk, sizeof(keydvt_out.ptk)); - if (result < 0) - goto error_wusbhc_set_ptk; - - result = wusb_dev_set_gtk(wusbhc, wusb_dev); - if (result < 0) { - dev_err(dev, "Set GTK for device: request failed: %d\n", - result); - goto error_wusbhc_set_gtk; - } - - /* Update the device's address from unauth to auth */ - if (usb_dev->authenticated == 0) { - result = wusb_dev_update_address(wusbhc, wusb_dev); - if (result < 0) - goto error_dev_update_address; - } - result = 0; - dev_info(dev, "device authenticated\n"); - -error_dev_update_address: -error_wusbhc_set_gtk: -error_wusbhc_set_ptk: -error_hs3: -error_hs2: -error_hs1: - memset(hs, 0, 3*sizeof(hs[0])); - memzero_explicit(&keydvt_out, sizeof(keydvt_out)); - memzero_explicit(&keydvt_in, sizeof(keydvt_in)); - memzero_explicit(&ccm_n, sizeof(ccm_n)); - memzero_explicit(mic, sizeof(mic)); - if (result < 0) - wusb_dev_set_encryption(usb_dev, 0); -error_dev_set_encryption: - kfree(hs); -error_kzalloc: - return result; -} - -/* - * Once all connected and authenticated devices have received the new - * GTK, switch the host to using it. - */ -static void wusbhc_gtk_rekey_work(struct work_struct *work) -{ - struct wusbhc *wusbhc = container_of(work, - struct wusbhc, gtk_rekey_work); - size_t key_size = sizeof(wusbhc->gtk.data); - int port_idx; - struct wusb_dev *wusb_dev, *wusb_dev_next; - LIST_HEAD(rekey_list); - - mutex_lock(&wusbhc->mutex); - /* generate the new key */ - wusbhc_generate_gtk(wusbhc); - /* roll the gtk index. */ - wusbhc->gtk_index = (wusbhc->gtk_index + 1) % (WUSB_KEY_INDEX_MAX + 1); - /* - * Save all connected devices on a list while holding wusbhc->mutex and - * take a reference to each one. Then submit the set key request to - * them after releasing the lock in order to avoid a deadlock. - */ - for (port_idx = 0; port_idx < wusbhc->ports_max; port_idx++) { - wusb_dev = wusbhc->port[port_idx].wusb_dev; - if (!wusb_dev || !wusb_dev->usb_dev - || !wusb_dev->usb_dev->authenticated) - continue; - - wusb_dev_get(wusb_dev); - list_add_tail(&wusb_dev->rekey_node, &rekey_list); - } - mutex_unlock(&wusbhc->mutex); - - /* Submit the rekey requests without holding wusbhc->mutex. */ - list_for_each_entry_safe(wusb_dev, wusb_dev_next, &rekey_list, - rekey_node) { - list_del_init(&wusb_dev->rekey_node); - dev_dbg(&wusb_dev->usb_dev->dev, - "%s: rekey device at port %d\n", - __func__, wusb_dev->port_idx); - - if (wusb_dev_set_gtk(wusbhc, wusb_dev) < 0) { - dev_err(&wusb_dev->usb_dev->dev, - "%s: rekey device at port %d failed\n", - __func__, wusb_dev->port_idx); - } - wusb_dev_put(wusb_dev); - } - - /* Switch the host controller to use the new GTK. */ - mutex_lock(&wusbhc->mutex); - wusbhc->set_gtk(wusbhc, wusbhc->gtk_tkid, - &wusbhc->gtk.descr.bKeyData, key_size); - mutex_unlock(&wusbhc->mutex); -} - -/** - * wusbhc_gtk_rekey - generate and distribute a new GTK - * @wusbhc: the WUSB host controller - * - * Generate a new GTK and distribute it to all connected and - * authenticated devices. When all devices have the new GTK, the host - * starts using it. - * - * This must be called after every device disconnect (see [WUSB] - * section 6.2.11.2). - */ -void wusbhc_gtk_rekey(struct wusbhc *wusbhc) -{ - /* - * We need to submit a URB to the downstream WUSB devices in order to - * change the group key. This can't be done while holding the - * wusbhc->mutex since that is also taken in the urb_enqueue routine - * and will cause a deadlock. Instead, queue a work item to do - * it when the lock is not held - */ - queue_work(wusbhc->wq_security, &wusbhc->gtk_rekey_work); -} |