diff options
| -rw-r--r-- | include/net/ieee802154.h | 9 | ||||
| -rw-r--r-- | include/net/ieee802154_netdev.h | 29 | ||||
| -rw-r--r-- | net/ieee802154/header_ops.c | 52 |
3 files changed, 83 insertions, 7 deletions
diff --git a/include/net/ieee802154.h b/include/net/ieee802154.h index c7ae0ac528d..0aa7122e8f1 100644 --- a/include/net/ieee802154.h +++ b/include/net/ieee802154.h @@ -79,6 +79,15 @@ #define IEEE802154_SCF_KEY_SHORT_INDEX 2 #define IEEE802154_SCF_KEY_HW_INDEX 3 +#define IEEE802154_SCF_SECLEVEL_NONE 0 +#define IEEE802154_SCF_SECLEVEL_MIC32 1 +#define IEEE802154_SCF_SECLEVEL_MIC64 2 +#define IEEE802154_SCF_SECLEVEL_MIC128 3 +#define IEEE802154_SCF_SECLEVEL_ENC 4 +#define IEEE802154_SCF_SECLEVEL_ENC_MIC32 5 +#define IEEE802154_SCF_SECLEVEL_ENC_MIC64 6 +#define IEEE802154_SCF_SECLEVEL_ENC_MIC128 7 + /* MAC footer size */ #define IEEE802154_MFR_SIZE 2 /* 2 octets */ diff --git a/include/net/ieee802154_netdev.h b/include/net/ieee802154_netdev.h index 5a719ca892f..6e4d3e1071b 100644 --- a/include/net/ieee802154_netdev.h +++ b/include/net/ieee802154_netdev.h @@ -27,6 +27,7 @@ #ifndef IEEE802154_NETDEVICE_H #define IEEE802154_NETDEVICE_H +#include <net/ieee802154.h> #include <net/af_ieee802154.h> #include <linux/netdevice.h> #include <linux/skbuff.h> @@ -114,6 +115,34 @@ int ieee802154_hdr_pull(struct sk_buff *skb, struct ieee802154_hdr *hdr); int ieee802154_hdr_peek_addrs(const struct sk_buff *skb, struct ieee802154_hdr *hdr); +/* parses the full 802.15.4 header a given skb and stores them into hdr, + * performing pan id decompression and length checks to be suitable for use in + * header_ops.parse + */ +int ieee802154_hdr_peek(const struct sk_buff *skb, struct ieee802154_hdr *hdr); + +int ieee802154_max_payload(const struct ieee802154_hdr *hdr); + +static inline int +ieee802154_sechdr_authtag_len(const struct ieee802154_sechdr *sec) +{ + switch (sec->level) { + case IEEE802154_SCF_SECLEVEL_MIC32: + case IEEE802154_SCF_SECLEVEL_ENC_MIC32: + return 4; + case IEEE802154_SCF_SECLEVEL_MIC64: + case IEEE802154_SCF_SECLEVEL_ENC_MIC64: + return 8; + case IEEE802154_SCF_SECLEVEL_MIC128: + case IEEE802154_SCF_SECLEVEL_ENC_MIC128: + return 16; + case IEEE802154_SCF_SECLEVEL_NONE: + case IEEE802154_SCF_SECLEVEL_ENC: + default: + return 0; + } +} + static inline int ieee802154_hdr_length(struct sk_buff *skb) { struct ieee802154_hdr hdr; diff --git a/net/ieee802154/header_ops.c b/net/ieee802154/header_ops.c index bed42a48408..c09294e39ca 100644 --- a/net/ieee802154/header_ops.c +++ b/net/ieee802154/header_ops.c @@ -195,15 +195,16 @@ ieee802154_hdr_get_sechdr(const u8 *buf, struct ieee802154_sechdr *hdr) return pos; } +static int ieee802154_sechdr_lengths[4] = { + [IEEE802154_SCF_KEY_IMPLICIT] = 5, + [IEEE802154_SCF_KEY_INDEX] = 6, + [IEEE802154_SCF_KEY_SHORT_INDEX] = 10, + [IEEE802154_SCF_KEY_HW_INDEX] = 14, +}; + static int ieee802154_hdr_sechdr_len(u8 sc) { - switch (IEEE802154_SCF_KEY_ID_MODE(sc)) { - case IEEE802154_SCF_KEY_IMPLICIT: return 5; - case IEEE802154_SCF_KEY_INDEX: return 6; - case IEEE802154_SCF_KEY_SHORT_INDEX: return 10; - case IEEE802154_SCF_KEY_HW_INDEX: return 14; - default: return -EINVAL; - } + return ieee802154_sechdr_lengths[IEEE802154_SCF_KEY_ID_MODE(sc)]; } static int ieee802154_hdr_minlen(const struct ieee802154_hdr *hdr) @@ -285,3 +286,40 @@ ieee802154_hdr_peek_addrs(const struct sk_buff *skb, struct ieee802154_hdr *hdr) return pos; } EXPORT_SYMBOL_GPL(ieee802154_hdr_peek_addrs); + +int +ieee802154_hdr_peek(const struct sk_buff *skb, struct ieee802154_hdr *hdr) +{ + const u8 *buf = skb_mac_header(skb); + int pos; + + pos = ieee802154_hdr_peek_addrs(skb, hdr); + if (pos < 0) + return -EINVAL; + + if (hdr->fc.security_enabled) { + u8 key_id_mode = IEEE802154_SCF_KEY_ID_MODE(*(buf + pos)); + int want = pos + ieee802154_sechdr_lengths[key_id_mode]; + + if (buf + want > skb_tail_pointer(skb)) + return -EINVAL; + + pos += ieee802154_hdr_get_sechdr(buf + pos, &hdr->sec); + } + + return pos; +} +EXPORT_SYMBOL_GPL(ieee802154_hdr_peek); + +int ieee802154_max_payload(const struct ieee802154_hdr *hdr) +{ + int hlen = ieee802154_hdr_minlen(hdr); + + if (hdr->fc.security_enabled) { + hlen += ieee802154_sechdr_lengths[hdr->sec.key_id_mode] - 1; + hlen += ieee802154_sechdr_authtag_len(&hdr->sec); + } + + return IEEE802154_MTU - hlen - IEEE802154_MFR_SIZE; +} +EXPORT_SYMBOL_GPL(ieee802154_max_payload); |