linux项目工程资料-基于Linux内核4.19.157版本，对网络协议栈部分源码进行研读并加以注释 .zip

/* * This is the new netlink-based wireless configuration interface. * * Copyright 2006-2010 Johannes Berg <johannes@sipsolutions.net> * Copyright 2013-2014 Intel Mobile Communications GmbH * Copyright 2015-2017 Intel Deutschland GmbH * Copyright (C) 2018 Intel Corporation */ #include <linux/if.h> #include <linux/module.h> #include <linux/err.h> #include <linux/slab.h> #include <linux/list.h> #include <linux/if_ether.h> #include <linux/ieee80211.h> #include <linux/nl80211.h> #include <linux/rtnetlink.h> #include <linux/netlink.h> #include <linux/nospec.h> #include <linux/etherdevice.h> #include <net/net_namespace.h> #include <net/genetlink.h> #include <net/cfg80211.h> #include <net/sock.h> #include <net/inet_connection_sock.h> #include "core.h" #include "nl80211.h" #include "reg.h" #include "rdev-ops.h" static int nl80211_crypto_settings(struct cfg80211_registered_device *rdev, struct genl_info *info, struct cfg80211_crypto_settings *settings, int cipher_limit); /* the netlink family */ static struct genl_family nl80211_fam; /* multicast groups */ enum nl80211_multicast_groups { NL80211_MCGRP_CONFIG, NL80211_MCGRP_SCAN, NL80211_MCGRP_REGULATORY, NL80211_MCGRP_MLME, NL80211_MCGRP_VENDOR, NL80211_MCGRP_NAN, NL80211_MCGRP_TESTMODE /* keep last - ifdef! */ }; static const struct genl_multicast_group nl80211_mcgrps[] = { [NL80211_MCGRP_CONFIG] = { .name = NL80211_MULTICAST_GROUP_CONFIG }, [NL80211_MCGRP_SCAN] = { .name = NL80211_MULTICAST_GROUP_SCAN }, [NL80211_MCGRP_REGULATORY] = { .name = NL80211_MULTICAST_GROUP_REG }, [NL80211_MCGRP_MLME] = { .name = NL80211_MULTICAST_GROUP_MLME }, [NL80211_MCGRP_VENDOR] = { .name = NL80211_MULTICAST_GROUP_VENDOR }, [NL80211_MCGRP_NAN] = { .name = NL80211_MULTICAST_GROUP_NAN }, #ifdef CONFIG_NL80211_TESTMODE [NL80211_MCGRP_TESTMODE] = { .name = NL80211_MULTICAST_GROUP_TESTMODE } #endif }; /* returns ERR_PTR values */ static struct wireless_dev * __cfg80211_wdev_from_attrs(struct net *netns, struct nlattr **attrs) { struct cfg80211_registered_device *rdev; struct wireless_dev *result = NULL; bool have_ifidx = attrs[NL80211_ATTR_IFINDEX]; bool have_wdev_id = attrs[NL80211_ATTR_WDEV]; u64 wdev_id; int wiphy_idx = -1; int ifidx = -1; ASSERT_RTNL(); if (!have_ifidx && !have_wdev_id) return ERR_PTR(-EINVAL); if (have_ifidx) ifidx = nla_get_u32(attrs[NL80211_ATTR_IFINDEX]); if (have_wdev_id) { wdev_id = nla_get_u64(attrs[NL80211_ATTR_WDEV]); wiphy_idx = wdev_id >> 32; } list_for_each_entry(rdev, &cfg80211_rdev_list, list) { struct wireless_dev *wdev; if (wiphy_net(&rdev->wiphy) != netns) continue; if (have_wdev_id && rdev->wiphy_idx != wiphy_idx) continue; list_for_each_entry(wdev, &rdev->wiphy.wdev_list, list) { if (have_ifidx && wdev->netdev && wdev->netdev->ifindex == ifidx) { result = wdev; break; } if (have_wdev_id && wdev->identifier == (u32)wdev_id) { result = wdev; break; } } if (result) break; } if (result) return result; return ERR_PTR(-ENODEV); } static struct cfg80211_registered_device * __cfg80211_rdev_from_attrs(struct net *netns, struct nlattr **attrs) { struct cfg80211_registered_device *rdev = NULL, *tmp; struct net_device *netdev; ASSERT_RTNL(); if (!attrs[NL80211_ATTR_WIPHY] && !attrs[NL80211_ATTR_IFINDEX] && !attrs[NL80211_ATTR_WDEV]) return ERR_PTR(-EINVAL); if (attrs[NL80211_ATTR_WIPHY]) rdev = cfg80211_rdev_by_wiphy_idx( nla_get_u32(attrs[NL80211_ATTR_WIPHY])); if (attrs[NL80211_ATTR_WDEV]) { u64 wdev_id = nla_get_u64(attrs[NL80211_ATTR_WDEV]); struct wireless_dev *wdev; bool found = false; tmp = cfg80211_rdev_by_wiphy_idx(wdev_id >> 32); if (tmp) { /* make sure wdev exists */ list_for_each_entry(wdev, &tmp->wiphy.wdev_list, list) { if (wdev->identifier != (u32)wdev_id) continue; found = true; break; } if (!found) tmp = NULL; if (rdev && tmp != rdev) return ERR_PTR(-EINVAL); rdev = tmp; } } if (attrs[NL80211_ATTR_IFINDEX]) { int ifindex = nla_get_u32(attrs[NL80211_ATTR_IFINDEX]); netdev = __dev_get_by_index(netns, ifindex); if (netdev) { if (netdev->ieee80211_ptr) tmp = wiphy_to_rdev( netdev->ieee80211_ptr->wiphy); else tmp = NULL; /* not wireless device -- return error */ if (!tmp) return ERR_PTR(-EINVAL); /* mismatch -- return error */ if (rdev && tmp != rdev) return ERR_PTR(-EINVAL); rdev = tmp; } } if (!rdev) return ERR_PTR(-ENODEV); if (netns != wiphy_net(&rdev->wiphy)) return ERR_PTR(-ENODEV); return rdev; } /* * This function returns a pointer to the driver * that the genl_info item that is passed refers to. * * The result of this can be a PTR_ERR and hence must * be checked with IS_ERR() for errors. */ static struct cfg80211_registered_device * cfg80211_get_dev_from_info(struct net *netns, struct genl_info *info) { return __cfg80211_rdev_from_attrs(netns, info->attrs); } static int validate_beacon_head(const struct nlattr *attr, struct netlink_ext_ack *extack) { const u8 *data = nla_data(attr); unsigned int len = nla_len(attr); const struct element *elem; const struct ieee80211_mgmt *mgmt = (void *)data; unsigned int fixedlen = offsetof(struct ieee80211_mgmt, u.beacon.variable); if (len < fixedlen) goto err; if (ieee80211_hdrlen(mgmt->frame_control) != offsetof(struct ieee80211_mgmt, u.beacon)) goto err; data += fixedlen; len -= fixedlen; for_each_element(elem, data, len) { /* nothing */ } if (for_each_element_completed(elem, data, len)) return 0; err: NL_SET_ERR_MSG_ATTR(extack, attr, "malformed beacon head"); return -EINVAL; } /* policy for the attributes */ static const struct nla_policy nl80211_policy[NUM_NL80211_ATTR] = { [NL80211_ATTR_WIPHY] = { .type = NLA_U32 }, [NL80211_ATTR_WIPHY_NAME] = { .type = NLA_NUL_STRING, .len = 20-1 }, [NL80211_ATTR_WIPHY_TXQ_PARAMS] = { .type = NLA_NESTED }, [NL80211_ATTR_WIPHY_FREQ] = { .type = NLA_U32 }, [NL80211_ATTR_WIPHY_CHANNEL_TYPE] = { .type = NLA_U32 }, [NL80211_ATTR_CHANNEL_WIDTH] = { .type = NLA_U32 }, [NL80211_ATTR_CENTER_FREQ1] = { .type = NLA_U32 }, [NL80211_ATTR_CENTER_FREQ2] = { .type = NLA_U32 }, [NL80211_ATTR_WIPHY_RETRY_SHORT] = { .type = NLA_U8 }, [NL80211_ATTR_WIPHY_RETRY_LONG] = { .type = NLA_U8 }, [NL80211_ATTR_WIPHY_FRAG_THRESHOLD] = { .type = NLA_U32 }, [NL80211_ATTR_WIPHY_RTS_THRESHOLD] = { .type = NLA_U32 }, [NL80211_ATTR_WIPHY_COVERAGE_CLASS] = { .type = NLA_U8 }, [NL80211_ATTR_WIPHY_DYN_ACK] = { .type = NLA_FLAG }, [NL80211_ATTR_IFTYPE] = { .type = NLA_U32 }, [NL80211_ATTR_IFINDEX] = { .type = NLA_U32 }, [NL80211_ATTR_IFNAME] = { .type = NLA_NUL_STRING, .len = IFNAMSIZ-1 }, [NL80211_ATTR_MAC] = { .len = ETH_ALEN }, [NL80211_ATTR_PREV_BSSID] = { .len = ETH_ALEN }, [NL80211_ATTR_KEY] = { .type = NLA_NESTED, }, [NL80211_ATTR_KEY_DATA] = { .type = NLA_BINARY, .len = WLAN_MAX_KEY_LEN }, [NL80211_ATTR_KEY_IDX] = { .type = NLA_U8 }, [NL80211_ATTR_KEY_CIPHER] = { .type = NLA_U32 }, [NL80211_ATTR_KEY_DEFAULT] = { .type = NLA_FLAG }, [NL80211_ATTR_KEY_SEQ] = { .type = NLA_BINARY, .len = 16 }, [NL80211_ATTR_KEY_TYPE] = { .type = NLA_U32 }, [NL80211_ATTR_BEACON_INTERVAL] = { .type = NLA_U32 }, [NL80211_ATTR_DTIM_PERIOD] = { .type = NLA_U32 }, [NL80211_ATTR_BEACON_HEAD] = { .type = NLA_BINARY, .len = IEEE80211_MAX_DATA_LEN }, [NL80211_ATTR_BEACON_TAIL] = { .type = NLA_BINARY, .len = IEEE80211_MAX_DATA_LEN }, [NL80211_ATTR_STA_AID] = { .type = NLA_U16 }, [NL80211_ATTR_STA_FLAGS] = { .type = NLA_NESTED }, [NL80211_ATTR_STA_LISTEN_INTERVAL] = { .type = NLA_U16 }, [NL80211_ATTR_STA_SUPPORTED_RATES] = { .type = NLA_BINARY, .len = NL80211_MAX_SUPP_RATES }, [NL80211_ATTR_STA_PLINK_ACTION] = { .type = NLA_U8 }, [NL80211_ATTR_STA_VLAN] = { .type = NLA_U32 }, [NL80211_ATTR_MNTR_FLAGS] = { /* NLA_NESTED can't be empty