wext: refactor
Refactor wext to
* split out iwpriv handling
* split out iwspy handling
* split out procfs support
* allow cfg80211 to have wireless extensions compat code
w/o CONFIG_WIRELESS_EXT
After this, drivers need to
- select WIRELESS_EXT - for wext support
- select WEXT_PRIV - for iwpriv support
- select WEXT_SPY - for iwspy support
except cfg80211 -- which gets new hooks in wext-core.c
and can then get wext handlers without CONFIG_WIRELESS_EXT.
Wireless extensions procfs support is auto-selected
based on PROC_FS and anything that requires the wext core
(i.e. WIRELESS_EXT or CFG80211_WEXT).
Signed-off-by: Johannes Berg <johannes@sipsolutions.net>
Signed-off-by: John W. Linville <linville@tuxdriver.com>
diff --git a/net/wireless/wext-priv.c b/net/wireless/wext-priv.c
new file mode 100644
index 0000000..a3c2277
--- /dev/null
+++ b/net/wireless/wext-priv.c
@@ -0,0 +1,248 @@
+/*
+ * This file implement the Wireless Extensions priv API.
+ *
+ * Authors : Jean Tourrilhes - HPL - <jt@hpl.hp.com>
+ * Copyright (c) 1997-2007 Jean Tourrilhes, All Rights Reserved.
+ * Copyright 2009 Johannes Berg <johannes@sipsolutions.net>
+ *
+ * (As all part of the Linux kernel, this file is GPL)
+ */
+#include <linux/wireless.h>
+#include <linux/netdevice.h>
+#include <net/iw_handler.h>
+#include <net/wext.h>
+
+int iw_handler_get_private(struct net_device * dev,
+ struct iw_request_info * info,
+ union iwreq_data * wrqu,
+ char * extra)
+{
+ /* Check if the driver has something to export */
+ if ((dev->wireless_handlers->num_private_args == 0) ||
+ (dev->wireless_handlers->private_args == NULL))
+ return -EOPNOTSUPP;
+
+ /* Check if there is enough buffer up there */
+ if (wrqu->data.length < dev->wireless_handlers->num_private_args) {
+ /* User space can't know in advance how large the buffer
+ * needs to be. Give it a hint, so that we can support
+ * any size buffer we want somewhat efficiently... */
+ wrqu->data.length = dev->wireless_handlers->num_private_args;
+ return -E2BIG;
+ }
+
+ /* Set the number of available ioctls. */
+ wrqu->data.length = dev->wireless_handlers->num_private_args;
+
+ /* Copy structure to the user buffer. */
+ memcpy(extra, dev->wireless_handlers->private_args,
+ sizeof(struct iw_priv_args) * wrqu->data.length);
+
+ return 0;
+}
+
+/* Size (in bytes) of the various private data types */
+static const char iw_priv_type_size[] = {
+ 0, /* IW_PRIV_TYPE_NONE */
+ 1, /* IW_PRIV_TYPE_BYTE */
+ 1, /* IW_PRIV_TYPE_CHAR */
+ 0, /* Not defined */
+ sizeof(__u32), /* IW_PRIV_TYPE_INT */
+ sizeof(struct iw_freq), /* IW_PRIV_TYPE_FLOAT */
+ sizeof(struct sockaddr), /* IW_PRIV_TYPE_ADDR */
+ 0, /* Not defined */
+};
+
+static int get_priv_size(__u16 args)
+{
+ int num = args & IW_PRIV_SIZE_MASK;
+ int type = (args & IW_PRIV_TYPE_MASK) >> 12;
+
+ return num * iw_priv_type_size[type];
+}
+
+static int adjust_priv_size(__u16 args, struct iw_point *iwp)
+{
+ int num = iwp->length;
+ int max = args & IW_PRIV_SIZE_MASK;
+ int type = (args & IW_PRIV_TYPE_MASK) >> 12;
+
+ /* Make sure the driver doesn't goof up */
+ if (max < num)
+ num = max;
+
+ return num * iw_priv_type_size[type];
+}
+
+/*
+ * Wrapper to call a private Wireless Extension handler.
+ * We do various checks and also take care of moving data between
+ * user space and kernel space.
+ * It's not as nice and slimline as the standard wrapper. The cause
+ * is struct iw_priv_args, which was not really designed for the
+ * job we are going here.
+ *
+ * IMPORTANT : This function prevent to set and get data on the same
+ * IOCTL and enforce the SET/GET convention. Not doing it would be
+ * far too hairy...
+ * If you need to set and get data at the same time, please don't use
+ * a iw_handler but process it in your ioctl handler (i.e. use the
+ * old driver API).
+ */
+static int get_priv_descr_and_size(struct net_device *dev, unsigned int cmd,
+ const struct iw_priv_args **descrp)
+{
+ const struct iw_priv_args *descr;
+ int i, extra_size;
+
+ descr = NULL;
+ for (i = 0; i < dev->wireless_handlers->num_private_args; i++) {
+ if (cmd == dev->wireless_handlers->private_args[i].cmd) {
+ descr = &dev->wireless_handlers->private_args[i];
+ break;
+ }
+ }
+
+ extra_size = 0;
+ if (descr) {
+ if (IW_IS_SET(cmd)) {
+ int offset = 0; /* For sub-ioctls */
+ /* Check for sub-ioctl handler */
+ if (descr->name[0] == '\0')
+ /* Reserve one int for sub-ioctl index */
+ offset = sizeof(__u32);
+
+ /* Size of set arguments */
+ extra_size = get_priv_size(descr->set_args);
+
+ /* Does it fits in iwr ? */
+ if ((descr->set_args & IW_PRIV_SIZE_FIXED) &&
+ ((extra_size + offset) <= IFNAMSIZ))
+ extra_size = 0;
+ } else {
+ /* Size of get arguments */
+ extra_size = get_priv_size(descr->get_args);
+
+ /* Does it fits in iwr ? */
+ if ((descr->get_args & IW_PRIV_SIZE_FIXED) &&
+ (extra_size <= IFNAMSIZ))
+ extra_size = 0;
+ }
+ }
+ *descrp = descr;
+ return extra_size;
+}
+
+static int ioctl_private_iw_point(struct iw_point *iwp, unsigned int cmd,
+ const struct iw_priv_args *descr,
+ iw_handler handler, struct net_device *dev,
+ struct iw_request_info *info, int extra_size)
+{
+ char *extra;
+ int err;
+
+ /* Check what user space is giving us */
+ if (IW_IS_SET(cmd)) {
+ if (!iwp->pointer && iwp->length != 0)
+ return -EFAULT;
+
+ if (iwp->length > (descr->set_args & IW_PRIV_SIZE_MASK))
+ return -E2BIG;
+ } else if (!iwp->pointer)
+ return -EFAULT;
+
+ extra = kmalloc(extra_size, GFP_KERNEL);
+ if (!extra)
+ return -ENOMEM;
+
+ /* If it is a SET, get all the extra data in here */
+ if (IW_IS_SET(cmd) && (iwp->length != 0)) {
+ if (copy_from_user(extra, iwp->pointer, extra_size)) {
+ err = -EFAULT;
+ goto out;
+ }
+ }
+
+ /* Call the handler */
+ err = handler(dev, info, (union iwreq_data *) iwp, extra);
+
+ /* If we have something to return to the user */
+ if (!err && IW_IS_GET(cmd)) {
+ /* Adjust for the actual length if it's variable,
+ * avoid leaking kernel bits outside.
+ */
+ if (!(descr->get_args & IW_PRIV_SIZE_FIXED))
+ extra_size = adjust_priv_size(descr->get_args, iwp);
+
+ if (copy_to_user(iwp->pointer, extra, extra_size))
+ err = -EFAULT;
+ }
+
+out:
+ kfree(extra);
+ return err;
+}
+
+int ioctl_private_call(struct net_device *dev, struct iwreq *iwr,
+ unsigned int cmd, struct iw_request_info *info,
+ iw_handler handler)
+{
+ int extra_size = 0, ret = -EINVAL;
+ const struct iw_priv_args *descr;
+
+ extra_size = get_priv_descr_and_size(dev, cmd, &descr);
+
+ /* Check if we have a pointer to user space data or not. */
+ if (extra_size == 0) {
+ /* No extra arguments. Trivial to handle */
+ ret = handler(dev, info, &(iwr->u), (char *) &(iwr->u));
+ } else {
+ ret = ioctl_private_iw_point(&iwr->u.data, cmd, descr,
+ handler, dev, info, extra_size);
+ }
+
+ /* Call commit handler if needed and defined */
+ if (ret == -EIWCOMMIT)
+ ret = call_commit_handler(dev);
+
+ return ret;
+}
+
+#ifdef CONFIG_COMPAT
+int compat_private_call(struct net_device *dev, struct iwreq *iwr,
+ unsigned int cmd, struct iw_request_info *info,
+ iw_handler handler)
+{
+ const struct iw_priv_args *descr;
+ int ret, extra_size;
+
+ extra_size = get_priv_descr_and_size(dev, cmd, &descr);
+
+ /* Check if we have a pointer to user space data or not. */
+ if (extra_size == 0) {
+ /* No extra arguments. Trivial to handle */
+ ret = handler(dev, info, &(iwr->u), (char *) &(iwr->u));
+ } else {
+ struct compat_iw_point *iwp_compat;
+ struct iw_point iwp;
+
+ iwp_compat = (struct compat_iw_point *) &iwr->u.data;
+ iwp.pointer = compat_ptr(iwp_compat->pointer);
+ iwp.length = iwp_compat->length;
+ iwp.flags = iwp_compat->flags;
+
+ ret = ioctl_private_iw_point(&iwp, cmd, descr,
+ handler, dev, info, extra_size);
+
+ iwp_compat->pointer = ptr_to_compat(iwp.pointer);
+ iwp_compat->length = iwp.length;
+ iwp_compat->flags = iwp.flags;
+ }
+
+ /* Call commit handler if needed and defined */
+ if (ret == -EIWCOMMIT)
+ ret = call_commit_handler(dev);
+
+ return ret;
+}
+#endif