diff options
| author | Kurt Kanzenbach <kurt@linutronix.de> | 2020-08-18 12:32:43 +0200 |
|---|---|---|
| committer | David S. Miller <davem@davemloft.net> | 2020-08-19 16:07:49 -0700 |
| commit | bdfbb63c314a6fb7d27dddd62f5a3e4f062b92bb (patch) | |
| tree | 40323ad304ef541518009a986fda4b571c0b0785 /net/core/ptp_classifier.c | |
| parent | f3ae59c0c01530ab48faf72cc678f92ad8aa7b4f (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>
Reviewed-by: Richard Cochran <richardcochran@gmail.com>
Reviewed-by: Florian Fainelli <f.fainelli@gmail.com>
Reviewed-by: Russell King <rmk+kernel@armlinux.org.uk>
Signed-off-by: David S. Miller <davem@davemloft.net>
Diffstat (limited to 'net/core/ptp_classifier.c')
| -rw-r--r-- | net/core/ptp_classifier.c | 30 |
1 files changed, 30 insertions, 0 deletions
diff --git a/net/core/ptp_classifier.c b/net/core/ptp_classifier.c index d964a5147f22..e33fde06d528 100644 --- a/net/core/ptp_classifier.c +++ b/net/core/ptp_classifier.c @@ -107,6 +107,36 @@ 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 *ptr = skb_mac_header(skb); + + 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 = { |