| /* |
| * Wireless utility functions |
| * |
| * Copyright 2007-2009 Johannes Berg <johannes@sipsolutions.net> |
| */ |
| #include <linux/bitops.h> |
| #include <linux/etherdevice.h> |
| #include <net/cfg80211.h> |
| #include <net/ip.h> |
| #include "core.h" |
| |
| struct ieee80211_rate * |
| ieee80211_get_response_rate(struct ieee80211_supported_band *sband, |
| u32 basic_rates, int bitrate) |
| { |
| struct ieee80211_rate *result = &sband->bitrates[0]; |
| int i; |
| |
| for (i = 0; i < sband->n_bitrates; i++) { |
| if (!(basic_rates & BIT(i))) |
| continue; |
| if (sband->bitrates[i].bitrate > bitrate) |
| continue; |
| result = &sband->bitrates[i]; |
| } |
| |
| return result; |
| } |
| EXPORT_SYMBOL(ieee80211_get_response_rate); |
| |
| int ieee80211_channel_to_frequency(int chan) |
| { |
| if (chan < 14) |
| return 2407 + chan * 5; |
| |
| if (chan == 14) |
| return 2484; |
| |
| /* FIXME: 802.11j 17.3.8.3.2 */ |
| return (chan + 1000) * 5; |
| } |
| EXPORT_SYMBOL(ieee80211_channel_to_frequency); |
| |
| int ieee80211_frequency_to_channel(int freq) |
| { |
| if (freq == 2484) |
| return 14; |
| |
| if (freq < 2484) |
| return (freq - 2407) / 5; |
| |
| /* FIXME: 802.11j 17.3.8.3.2 */ |
| return freq/5 - 1000; |
| } |
| EXPORT_SYMBOL(ieee80211_frequency_to_channel); |
| |
| struct ieee80211_channel *__ieee80211_get_channel(struct wiphy *wiphy, |
| int freq) |
| { |
| enum ieee80211_band band; |
| struct ieee80211_supported_band *sband; |
| int i; |
| |
| for (band = 0; band < IEEE80211_NUM_BANDS; band++) { |
| sband = wiphy->bands[band]; |
| |
| if (!sband) |
| continue; |
| |
| for (i = 0; i < sband->n_channels; i++) { |
| if (sband->channels[i].center_freq == freq) |
| return &sband->channels[i]; |
| } |
| } |
| |
| return NULL; |
| } |
| EXPORT_SYMBOL(__ieee80211_get_channel); |
| |
| static void set_mandatory_flags_band(struct ieee80211_supported_band *sband, |
| enum ieee80211_band band) |
| { |
| int i, want; |
| |
| switch (band) { |
| case IEEE80211_BAND_5GHZ: |
| want = 3; |
| for (i = 0; i < sband->n_bitrates; i++) { |
| if (sband->bitrates[i].bitrate == 60 || |
| sband->bitrates[i].bitrate == 120 || |
| sband->bitrates[i].bitrate == 240) { |
| sband->bitrates[i].flags |= |
| IEEE80211_RATE_MANDATORY_A; |
| want--; |
| } |
| } |
| WARN_ON(want); |
| break; |
| case IEEE80211_BAND_2GHZ: |
| want = 7; |
| for (i = 0; i < sband->n_bitrates; i++) { |
| if (sband->bitrates[i].bitrate == 10) { |
| sband->bitrates[i].flags |= |
| IEEE80211_RATE_MANDATORY_B | |
| IEEE80211_RATE_MANDATORY_G; |
| want--; |
| } |
| |
| if (sband->bitrates[i].bitrate == 20 || |
| sband->bitrates[i].bitrate == 55 || |
| sband->bitrates[i].bitrate == 110 || |
| sband->bitrates[i].bitrate == 60 || |
| sband->bitrates[i].bitrate == 120 || |
| sband->bitrates[i].bitrate == 240) { |
| sband->bitrates[i].flags |= |
| IEEE80211_RATE_MANDATORY_G; |
| want--; |
| } |
| |
| if (sband->bitrates[i].bitrate != 10 && |
| sband->bitrates[i].bitrate != 20 && |
| sband->bitrates[i].bitrate != 55 && |
| sband->bitrates[i].bitrate != 110) |
| sband->bitrates[i].flags |= |
| IEEE80211_RATE_ERP_G; |
| } |
| WARN_ON(want != 0 && want != 3 && want != 6); |
| break; |
| case IEEE80211_NUM_BANDS: |
| WARN_ON(1); |
| break; |
| } |
| } |
| |
| void ieee80211_set_bitrate_flags(struct wiphy *wiphy) |
| { |
| enum ieee80211_band band; |
| |
| for (band = 0; band < IEEE80211_NUM_BANDS; band++) |
| if (wiphy->bands[band]) |
| set_mandatory_flags_band(wiphy->bands[band], band); |
| } |
| |
| int cfg80211_validate_key_settings(struct key_params *params, int key_idx, |
| const u8 *mac_addr) |
| { |
| if (key_idx > 5) |
| return -EINVAL; |
| |
| /* |
| * Disallow pairwise keys with non-zero index unless it's WEP |
| * (because current deployments use pairwise WEP keys with |
| * non-zero indizes but 802.11i clearly specifies to use zero) |
| */ |
| if (mac_addr && key_idx && |
| params->cipher != WLAN_CIPHER_SUITE_WEP40 && |
| params->cipher != WLAN_CIPHER_SUITE_WEP104) |
| return -EINVAL; |
| |
| switch (params->cipher) { |
| case WLAN_CIPHER_SUITE_WEP40: |
| if (params->key_len != WLAN_KEY_LEN_WEP40) |
| return -EINVAL; |
| break; |
| case WLAN_CIPHER_SUITE_TKIP: |
| if (params->key_len != WLAN_KEY_LEN_TKIP) |
| return -EINVAL; |
| break; |
| case WLAN_CIPHER_SUITE_CCMP: |
| if (params->key_len != WLAN_KEY_LEN_CCMP) |
| return -EINVAL; |
| break; |
| case WLAN_CIPHER_SUITE_WEP104: |
| if (params->key_len != WLAN_KEY_LEN_WEP104) |
| return -EINVAL; |
| break; |
| case WLAN_CIPHER_SUITE_AES_CMAC: |
| if (params->key_len != WLAN_KEY_LEN_AES_CMAC) |
| return -EINVAL; |
| break; |
| default: |
| return -EINVAL; |
| } |
| |
| if (params->seq) { |
| switch (params->cipher) { |
| case WLAN_CIPHER_SUITE_WEP40: |
| case WLAN_CIPHER_SUITE_WEP104: |
| /* These ciphers do not use key sequence */ |
| return -EINVAL; |
| case WLAN_CIPHER_SUITE_TKIP: |
| case WLAN_CIPHER_SUITE_CCMP: |
| case WLAN_CIPHER_SUITE_AES_CMAC: |
| if (params->seq_len != 6) |
| return -EINVAL; |
| break; |
| } |
| } |
| |
| return 0; |
| } |
| |
| /* See IEEE 802.1H for LLC/SNAP encapsulation/decapsulation */ |
| /* Ethernet-II snap header (RFC1042 for most EtherTypes) */ |
| const unsigned char rfc1042_header[] __aligned(2) = |
| { 0xaa, 0xaa, 0x03, 0x00, 0x00, 0x00 }; |
| EXPORT_SYMBOL(rfc1042_header); |
| |
| /* Bridge-Tunnel header (for EtherTypes ETH_P_AARP and ETH_P_IPX) */ |
| const unsigned char bridge_tunnel_header[] __aligned(2) = |
| { 0xaa, 0xaa, 0x03, 0x00, 0x00, 0xf8 }; |
| EXPORT_SYMBOL(bridge_tunnel_header); |
| |
| unsigned int ieee80211_hdrlen(__le16 fc) |
| { |
| unsigned int hdrlen = 24; |
| |
| if (ieee80211_is_data(fc)) { |
| if (ieee80211_has_a4(fc)) |
| hdrlen = 30; |
| if (ieee80211_is_data_qos(fc)) |
| hdrlen += IEEE80211_QOS_CTL_LEN; |
| goto out; |
| } |
| |
| if (ieee80211_is_ctl(fc)) { |
| /* |
| * ACK and CTS are 10 bytes, all others 16. To see how |
| * to get this condition consider |
| * subtype mask: 0b0000000011110000 (0x00F0) |
| * ACK subtype: 0b0000000011010000 (0x00D0) |
| * CTS subtype: 0b0000000011000000 (0x00C0) |
| * bits that matter: ^^^ (0x00E0) |
| * value of those: 0b0000000011000000 (0x00C0) |
| */ |
| if ((fc & cpu_to_le16(0x00E0)) == cpu_to_le16(0x00C0)) |
| hdrlen = 10; |
| else |
| hdrlen = 16; |
| } |
| out: |
| return hdrlen; |
| } |
| EXPORT_SYMBOL(ieee80211_hdrlen); |
| |
| unsigned int ieee80211_get_hdrlen_from_skb(const struct sk_buff *skb) |
| { |
| const struct ieee80211_hdr *hdr = |
| (const struct ieee80211_hdr *)skb->data; |
| unsigned int hdrlen; |
| |
| if (unlikely(skb->len < 10)) |
| return 0; |
| hdrlen = ieee80211_hdrlen(hdr->frame_control); |
| if (unlikely(hdrlen > skb->len)) |
| return 0; |
| return hdrlen; |
| } |
| EXPORT_SYMBOL(ieee80211_get_hdrlen_from_skb); |
| |
| static int ieee80211_get_mesh_hdrlen(struct ieee80211s_hdr *meshhdr) |
| { |
| int ae = meshhdr->flags & MESH_FLAGS_AE; |
| /* 7.1.3.5a.2 */ |
| switch (ae) { |
| case 0: |
| return 6; |
| case 1: |
| return 12; |
| case 2: |
| return 18; |
| case 3: |
| return 24; |
| default: |
| return 6; |
| } |
| } |
| |
| int ieee80211_data_to_8023(struct sk_buff *skb, u8 *addr, |
| enum nl80211_iftype iftype) |
| { |
| struct ieee80211_hdr *hdr = (struct ieee80211_hdr *) skb->data; |
| u16 hdrlen, ethertype; |
| u8 *payload; |
| u8 dst[ETH_ALEN]; |
| u8 src[ETH_ALEN] __aligned(2); |
| |
| if (unlikely(!ieee80211_is_data_present(hdr->frame_control))) |
| return -1; |
| |
| hdrlen = ieee80211_hdrlen(hdr->frame_control); |
| |
| /* convert IEEE 802.11 header + possible LLC headers into Ethernet |
| * header |
| * IEEE 802.11 address fields: |
| * ToDS FromDS Addr1 Addr2 Addr3 Addr4 |
| * 0 0 DA SA BSSID n/a |
| * 0 1 DA BSSID SA n/a |
| * 1 0 BSSID SA DA n/a |
| * 1 1 RA TA DA SA |
| */ |
| memcpy(dst, ieee80211_get_DA(hdr), ETH_ALEN); |
| memcpy(src, ieee80211_get_SA(hdr), ETH_ALEN); |
| |
| switch (hdr->frame_control & |
| cpu_to_le16(IEEE80211_FCTL_TODS | IEEE80211_FCTL_FROMDS)) { |
| case cpu_to_le16(IEEE80211_FCTL_TODS): |
| if (unlikely(iftype != NL80211_IFTYPE_AP && |
| iftype != NL80211_IFTYPE_AP_VLAN)) |
| return -1; |
| break; |
| case cpu_to_le16(IEEE80211_FCTL_TODS | IEEE80211_FCTL_FROMDS): |
| if (unlikely(iftype != NL80211_IFTYPE_WDS && |
| iftype != NL80211_IFTYPE_MESH_POINT)) |
| return -1; |
| if (iftype == NL80211_IFTYPE_MESH_POINT) { |
| struct ieee80211s_hdr *meshdr = |
| (struct ieee80211s_hdr *) (skb->data + hdrlen); |
| hdrlen += ieee80211_get_mesh_hdrlen(meshdr); |
| if (meshdr->flags & MESH_FLAGS_AE_A5_A6) { |
| memcpy(dst, meshdr->eaddr1, ETH_ALEN); |
| memcpy(src, meshdr->eaddr2, ETH_ALEN); |
| } |
| } |
| break; |
| case cpu_to_le16(IEEE80211_FCTL_FROMDS): |
| if (iftype != NL80211_IFTYPE_STATION || |
| (is_multicast_ether_addr(dst) && |
| !compare_ether_addr(src, addr))) |
| return -1; |
| break; |
| case cpu_to_le16(0): |
| if (iftype != NL80211_IFTYPE_ADHOC) |
| return -1; |
| break; |
| } |
| |
| if (unlikely(skb->len - hdrlen < 8)) |
| return -1; |
| |
| payload = skb->data + hdrlen; |
| ethertype = (payload[6] << 8) | payload[7]; |
| |
| if (likely((compare_ether_addr(payload, rfc1042_header) == 0 && |
| ethertype != ETH_P_AARP && ethertype != ETH_P_IPX) || |
| compare_ether_addr(payload, bridge_tunnel_header) == 0)) { |
| /* remove RFC1042 or Bridge-Tunnel encapsulation and |
| * replace EtherType */ |
| skb_pull(skb, hdrlen + 6); |
| memcpy(skb_push(skb, ETH_ALEN), src, ETH_ALEN); |
| memcpy(skb_push(skb, ETH_ALEN), dst, ETH_ALEN); |
| } else { |
| struct ethhdr *ehdr; |
| __be16 len; |
| |
| skb_pull(skb, hdrlen); |
| len = htons(skb->len); |
| ehdr = (struct ethhdr *) skb_push(skb, sizeof(struct ethhdr)); |
| memcpy(ehdr->h_dest, dst, ETH_ALEN); |
| memcpy(ehdr->h_source, src, ETH_ALEN); |
| ehdr->h_proto = len; |
| } |
| return 0; |
| } |
| EXPORT_SYMBOL(ieee80211_data_to_8023); |
| |
| int ieee80211_data_from_8023(struct sk_buff *skb, u8 *addr, |
| enum nl80211_iftype iftype, u8 *bssid, bool qos) |
| { |
| struct ieee80211_hdr hdr; |
| u16 hdrlen, ethertype; |
| __le16 fc; |
| const u8 *encaps_data; |
| int encaps_len, skip_header_bytes; |
| int nh_pos, h_pos; |
| int head_need; |
| |
| if (unlikely(skb->len < ETH_HLEN)) |
| return -EINVAL; |
| |
| nh_pos = skb_network_header(skb) - skb->data; |
| h_pos = skb_transport_header(skb) - skb->data; |
| |
| /* convert Ethernet header to proper 802.11 header (based on |
| * operation mode) */ |
| ethertype = (skb->data[12] << 8) | skb->data[13]; |
| fc = cpu_to_le16(IEEE80211_FTYPE_DATA | IEEE80211_STYPE_DATA); |
| |
| switch (iftype) { |
| case NL80211_IFTYPE_AP: |
| case NL80211_IFTYPE_AP_VLAN: |
| fc |= cpu_to_le16(IEEE80211_FCTL_FROMDS); |
| /* DA BSSID SA */ |
| memcpy(hdr.addr1, skb->data, ETH_ALEN); |
| memcpy(hdr.addr2, addr, ETH_ALEN); |
| memcpy(hdr.addr3, skb->data + ETH_ALEN, ETH_ALEN); |
| hdrlen = 24; |
| break; |
| case NL80211_IFTYPE_STATION: |
| fc |= cpu_to_le16(IEEE80211_FCTL_TODS); |
| /* BSSID SA DA */ |
| memcpy(hdr.addr1, bssid, ETH_ALEN); |
| memcpy(hdr.addr2, skb->data + ETH_ALEN, ETH_ALEN); |
| memcpy(hdr.addr3, skb->data, ETH_ALEN); |
| hdrlen = 24; |
| break; |
| case NL80211_IFTYPE_ADHOC: |
| /* DA SA BSSID */ |
| memcpy(hdr.addr1, skb->data, ETH_ALEN); |
| memcpy(hdr.addr2, skb->data + ETH_ALEN, ETH_ALEN); |
| memcpy(hdr.addr3, bssid, ETH_ALEN); |
| hdrlen = 24; |
| break; |
| default: |
| return -EOPNOTSUPP; |
| } |
| |
| if (qos) { |
| fc |= cpu_to_le16(IEEE80211_STYPE_QOS_DATA); |
| hdrlen += 2; |
| } |
| |
| hdr.frame_control = fc; |
| hdr.duration_id = 0; |
| hdr.seq_ctrl = 0; |
| |
| skip_header_bytes = ETH_HLEN; |
| if (ethertype == ETH_P_AARP || ethertype == ETH_P_IPX) { |
| encaps_data = bridge_tunnel_header; |
| encaps_len = sizeof(bridge_tunnel_header); |
| skip_header_bytes -= 2; |
| } else if (ethertype > 0x600) { |
| encaps_data = rfc1042_header; |
| encaps_len = sizeof(rfc1042_header); |
| skip_header_bytes -= 2; |
| } else { |
| encaps_data = NULL; |
| encaps_len = 0; |
| } |
| |
| skb_pull(skb, skip_header_bytes); |
| nh_pos -= skip_header_bytes; |
| h_pos -= skip_header_bytes; |
| |
| head_need = hdrlen + encaps_len - skb_headroom(skb); |
| |
| if (head_need > 0 || skb_cloned(skb)) { |
| head_need = max(head_need, 0); |
| if (head_need) |
| skb_orphan(skb); |
| |
| if (pskb_expand_head(skb, head_need, 0, GFP_ATOMIC)) { |
| printk(KERN_ERR "failed to reallocate Tx buffer\n"); |
| return -ENOMEM; |
| } |
| skb->truesize += head_need; |
| } |
| |
| if (encaps_data) { |
| memcpy(skb_push(skb, encaps_len), encaps_data, encaps_len); |
| nh_pos += encaps_len; |
| h_pos += encaps_len; |
| } |
| |
| memcpy(skb_push(skb, hdrlen), &hdr, hdrlen); |
| |
| nh_pos += hdrlen; |
| h_pos += hdrlen; |
| |
| /* Update skb pointers to various headers since this modified frame |
| * is going to go through Linux networking code that may potentially |
| * need things like pointer to IP header. */ |
| skb_set_mac_header(skb, 0); |
| skb_set_network_header(skb, nh_pos); |
| skb_set_transport_header(skb, h_pos); |
| |
| return 0; |
| } |
| EXPORT_SYMBOL(ieee80211_data_from_8023); |
| |
| /* Given a data frame determine the 802.1p/1d tag to use. */ |
| unsigned int cfg80211_classify8021d(struct sk_buff *skb) |
| { |
| unsigned int dscp; |
| |
| /* skb->priority values from 256->263 are magic values to |
| * directly indicate a specific 802.1d priority. This is used |
| * to allow 802.1d priority to be passed directly in from VLAN |
| * tags, etc. |
| */ |
| if (skb->priority >= 256 && skb->priority <= 263) |
| return skb->priority - 256; |
| |
| switch (skb->protocol) { |
| case htons(ETH_P_IP): |
| dscp = ip_hdr(skb)->tos & 0xfc; |
| break; |
| default: |
| return 0; |
| } |
| |
| return dscp >> 5; |
| } |
| EXPORT_SYMBOL(cfg80211_classify8021d); |