diff options
| author | Kurt Kanzenbach <kurt@linutronix.de> | 2020-07-30 10:00:40 +0200 |
|---|---|---|
| committer | Russell King <rmk+kernel@armlinux.org.uk> | 2020-08-03 22:04:22 +0100 |
| commit | 9d1bbf391734e6850b04c852f9877ec63793841f (patch) | |
| tree | 57129ae8539c5299d860739bb1df0769fbea4642 /net | |
| parent | c23fa81ecec8d33042f2a923c7f84376a628816c (diff) | |
ptp: Add generic ptp v2 header parsing function
Reason: A lot of the ptp drivers - which implement hardware time stamping - need
specific fields such as the sequence id from the ptp v2 header. Currently all
drivers implement that themselves.
Introduce a generic function to retrieve a pointer to the start of the ptp v2
header.
Suggested-by: Russell King <rmk+kernel@armlinux.org.uk>
Signed-off-by: Kurt Kanzenbach <kurt@linutronix.de>
Signed-off-by: Russell King <rmk+kernel@armlinux.org.uk>
Diffstat (limited to 'net')
| -rw-r--r-- | net/core/ptp_classifier.c | 31 |
1 files changed, 31 insertions, 0 deletions
diff --git a/net/core/ptp_classifier.c b/net/core/ptp_classifier.c index d964a5147f22..41f373477812 100644 --- a/net/core/ptp_classifier.c +++ b/net/core/ptp_classifier.c @@ -107,6 +107,37 @@ unsigned int ptp_classify_raw(const struct sk_buff *skb) } EXPORT_SYMBOL_GPL(ptp_classify_raw); +struct ptp_header *ptp_parse_header(struct sk_buff *skb, unsigned int type) +{ + u8 *data = skb_mac_header(skb); + u8 *ptr = data; + + if (type & PTP_CLASS_VLAN) + ptr += VLAN_HLEN; + + switch (type & PTP_CLASS_PMASK) { + case PTP_CLASS_IPV4: + ptr += IPV4_HLEN(ptr) + UDP_HLEN; + break; + case PTP_CLASS_IPV6: + ptr += IP6_HLEN + UDP_HLEN; + break; + case PTP_CLASS_L2: + break; + default: + return NULL; + } + + ptr += ETH_HLEN; + + /* Ensure that the entire header is present in this packet. */ + if (ptr + sizeof(struct ptp_header) > skb->data + skb->len) + return NULL; + + return (struct ptp_header *)ptr; +} +EXPORT_SYMBOL_GPL(ptp_parse_header); + void __init ptp_classifier_init(void) { static struct sock_filter ptp_filter[] __initdata = { |