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authorOliver Neukum <oneukum@suse.com>2015-09-07 17:05:40 +0300
committerDavid S. Miller <davem@davemloft.net>2015-09-15 22:43:27 +0300
commit823bd3433424aa959499e6fd8f2da842430a8d42 (patch)
treef16918ee3fcabe87461cc60fd55a37f48ac75b50 /drivers/net/usb/cdc_ether.c
parent77b0a099674ac1c43b631445d8d50453e4805b29 (diff)
downloadlinux-823bd3433424aa959499e6fd8f2da842430a8d42.tar.xz
cdc-ether: switch to common CDC parser
This patch uses the common parser to parse extra CDC headers in order to reduce code duplication. Signed-off-by: Oliver Neukum <oneukum@suse.com> Signed-off-by: David S. Miller <davem@davemloft.net>
Diffstat (limited to 'drivers/net/usb/cdc_ether.c')
-rw-r--r--drivers/net/usb/cdc_ether.c230
1 files changed, 81 insertions, 149 deletions
diff --git a/drivers/net/usb/cdc_ether.c b/drivers/net/usb/cdc_ether.c
index 35a2bffe848a..c78d3cb1b464 100644
--- a/drivers/net/usb/cdc_ether.c
+++ b/drivers/net/usb/cdc_ether.c
@@ -112,8 +112,7 @@ int usbnet_generic_cdc_bind(struct usbnet *dev, struct usb_interface *intf)
int rndis;
bool android_rndis_quirk = false;
struct usb_driver *driver = driver_of(intf);
- struct usb_cdc_mdlm_desc *desc = NULL;
- struct usb_cdc_mdlm_detail_desc *detail = NULL;
+ struct usb_cdc_parsed_header header;
if (sizeof(dev->data) < sizeof(*info))
return -EDOM;
@@ -155,156 +154,89 @@ int usbnet_generic_cdc_bind(struct usbnet *dev, struct usb_interface *intf)
memset(info, 0, sizeof(*info));
info->control = intf;
- while (len > 3) {
- if (buf[1] != USB_DT_CS_INTERFACE)
- goto next_desc;
-
- /* use bDescriptorSubType to identify the CDC descriptors.
- * We expect devices with CDC header and union descriptors.
- * For CDC Ethernet we need the ethernet descriptor.
- * For RNDIS, ignore two (pointless) CDC modem descriptors
- * in favor of a complicated OID-based RPC scheme doing what
- * CDC Ethernet achieves with a simple descriptor.
- */
- switch (buf[2]) {
- case USB_CDC_HEADER_TYPE:
- if (info->header) {
- dev_dbg(&intf->dev, "extra CDC header\n");
- goto bad_desc;
- }
- info->header = (void *) buf;
- if (info->header->bLength != sizeof(*info->header)) {
- dev_dbg(&intf->dev, "CDC header len %u\n",
- info->header->bLength);
- goto bad_desc;
- }
- break;
- case USB_CDC_ACM_TYPE:
- /* paranoia: disambiguate a "real" vendor-specific
- * modem interface from an RNDIS non-modem.
- */
- if (rndis) {
- struct usb_cdc_acm_descriptor *acm;
-
- acm = (void *) buf;
- if (acm->bmCapabilities) {
- dev_dbg(&intf->dev,
- "ACM capabilities %02x, "
- "not really RNDIS?\n",
- acm->bmCapabilities);
- goto bad_desc;
- }
- }
- break;
- case USB_CDC_UNION_TYPE:
- if (info->u) {
- dev_dbg(&intf->dev, "extra CDC union\n");
- goto bad_desc;
- }
- info->u = (void *) buf;
- if (info->u->bLength != sizeof(*info->u)) {
- dev_dbg(&intf->dev, "CDC union len %u\n",
- info->u->bLength);
- goto bad_desc;
- }
-
- /* we need a master/control interface (what we're
- * probed with) and a slave/data interface; union
- * descriptors sort this all out.
- */
- info->control = usb_ifnum_to_if(dev->udev,
- info->u->bMasterInterface0);
- info->data = usb_ifnum_to_if(dev->udev,
- info->u->bSlaveInterface0);
- if (!info->control || !info->data) {
- dev_dbg(&intf->dev,
- "master #%u/%p slave #%u/%p\n",
- info->u->bMasterInterface0,
- info->control,
- info->u->bSlaveInterface0,
- info->data);
- /* fall back to hard-wiring for RNDIS */
- if (rndis) {
- android_rndis_quirk = true;
- goto next_desc;
- }
- goto bad_desc;
- }
- if (info->control != intf) {
- dev_dbg(&intf->dev, "bogus CDC Union\n");
- /* Ambit USB Cable Modem (and maybe others)
- * interchanges master and slave interface.
- */
- if (info->data == intf) {
- info->data = info->control;
- info->control = intf;
- } else
- goto bad_desc;
- }
-
- /* some devices merge these - skip class check */
- if (info->control == info->data)
- goto next_desc;
-
- /* a data interface altsetting does the real i/o */
- d = &info->data->cur_altsetting->desc;
- if (d->bInterfaceClass != USB_CLASS_CDC_DATA) {
- dev_dbg(&intf->dev, "slave class %u\n",
- d->bInterfaceClass);
- goto bad_desc;
- }
- break;
- case USB_CDC_ETHERNET_TYPE:
- if (info->ether) {
- dev_dbg(&intf->dev, "extra CDC ether\n");
- goto bad_desc;
- }
- info->ether = (void *) buf;
- if (info->ether->bLength != sizeof(*info->ether)) {
- dev_dbg(&intf->dev, "CDC ether len %u\n",
- info->ether->bLength);
- goto bad_desc;
- }
- dev->hard_mtu = le16_to_cpu(
- info->ether->wMaxSegmentSize);
- /* because of Zaurus, we may be ignoring the host
- * side link address we were given.
- */
- break;
- case USB_CDC_MDLM_TYPE:
- if (desc) {
- dev_dbg(&intf->dev, "extra MDLM descriptor\n");
- goto bad_desc;
- }
-
- desc = (void *)buf;
-
- if (desc->bLength != sizeof(*desc))
- goto bad_desc;
-
- if (memcmp(&desc->bGUID, mbm_guid, 16))
- goto bad_desc;
- break;
- case USB_CDC_MDLM_DETAIL_TYPE:
- if (detail) {
- dev_dbg(&intf->dev, "extra MDLM detail descriptor\n");
- goto bad_desc;
- }
-
- detail = (void *)buf;
-
- if (detail->bGuidDescriptorType == 0) {
- if (detail->bLength < (sizeof(*detail) + 1))
- goto bad_desc;
- } else
- goto bad_desc;
- break;
+
+ cdc_parse_cdc_header(&header, intf, buf, len);
+
+ info->u = header.usb_cdc_union_desc;
+ info->header = header.usb_cdc_header_desc;
+ info->ether = header.usb_cdc_ether_desc;
+ /* we need a master/control interface (what we're
+ * probed with) and a slave/data interface; union
+ * descriptors sort this all out.
+ */
+ info->control = usb_ifnum_to_if(dev->udev,
+ info->u->bMasterInterface0);
+ info->data = usb_ifnum_to_if(dev->udev,
+ info->u->bSlaveInterface0);
+ if (!info->control || !info->data) {
+ dev_dbg(&intf->dev,
+ "master #%u/%p slave #%u/%p\n",
+ info->u->bMasterInterface0,
+ info->control,
+ info->u->bSlaveInterface0,
+ info->data);
+ /* fall back to hard-wiring for RNDIS */
+ if (rndis) {
+ android_rndis_quirk = true;
+ goto skip;
}
-next_desc:
- len -= buf[0]; /* bLength */
- buf += buf[0];
+ goto bad_desc;
+ }
+ if (info->control != intf) {
+ dev_dbg(&intf->dev, "bogus CDC Union\n");
+ /* Ambit USB Cable Modem (and maybe others)
+ * interchanges master and slave interface.
+ */
+ if (info->data == intf) {
+ info->data = info->control;
+ info->control = intf;
+ } else
+ goto bad_desc;
+ }
+
+ /* some devices merge these - skip class check */
+ if (info->control == info->data)
+ goto skip;
+
+ /* a data interface altsetting does the real i/o */
+ d = &info->data->cur_altsetting->desc;
+ if (d->bInterfaceClass != USB_CLASS_CDC_DATA) {
+ dev_dbg(&intf->dev, "slave class %u\n",
+ d->bInterfaceClass);
+ goto bad_desc;
+ }
+skip:
+ if ( rndis &&
+ header.usb_cdc_acm_descriptor &&
+ header.usb_cdc_acm_descriptor->bmCapabilities) {
+ dev_dbg(&intf->dev,
+ "ACM capabilities %02x, not really RNDIS?\n",
+ header.usb_cdc_acm_descriptor->bmCapabilities);
+ goto bad_desc;
}
+ if (header.usb_cdc_ether_desc) {
+ dev->hard_mtu = le16_to_cpu(info->ether->wMaxSegmentSize);
+ /* because of Zaurus, we may be ignoring the host
+ * side link address we were given.
+ */
+ }
+
+ if (header.usb_cdc_mdlm_desc &&
+ memcmp(header.usb_cdc_mdlm_desc->bGUID, mbm_guid, 16)) {
+ dev_dbg(&intf->dev, "GUID doesn't match\n");
+ goto bad_desc;
+ }
+
+ if (header.usb_cdc_mdlm_detail_desc &&
+ header.usb_cdc_mdlm_detail_desc->bLength <
+ (sizeof(struct usb_cdc_mdlm_detail_desc) + 1)) {
+ dev_dbg(&intf->dev, "Descriptor too short\n");
+ goto bad_desc;
+ }
+
+
+
/* Microsoft ActiveSync based and some regular RNDIS devices lack the
* CDC descriptors, so we'll hard-wire the interfaces and not check
* for descriptors.