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| author | Alexander Drozdov <al.drozdov@gmail.com> | 2015-03-23 09:11:13 +0300 |
|---|---|---|
| committer | David S. Miller <davem@davemloft.net> | 2015-03-23 22:01:28 -0400 |
| commit | 682f048bd49449f4ab978664a7f69a44a74e3caa (patch) | |
| tree | 4b623e8ddd2e4f874947e3c9f128591661dd10e8 | |
| parent | 68c2e5de360411674d9821ee2b46f5d8ee965161 (diff) | |
| download | blackbird-op-linux-682f048bd49449f4ab978664a7f69a44a74e3caa.tar.gz blackbird-op-linux-682f048bd49449f4ab978664a7f69a44a74e3caa.zip | |
af_packet: pass checksum validation status to the user
Introduce TP_STATUS_CSUM_VALID tp_status flag to tell the
af_packet user that at least the transport header checksum
has been already validated.
For now, the flag may be set for incoming packets only.
Signed-off-by: Alexander Drozdov <al.drozdov@gmail.com>
Cc: Willem de Bruijn <willemb@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
| -rw-r--r-- | Documentation/networking/packet_mmap.txt | 13 | ||||
| -rw-r--r-- | include/uapi/linux/if_packet.h | 1 | ||||
| -rw-r--r-- | net/packet/af_packet.c | 9 |
3 files changed, 20 insertions, 3 deletions
diff --git a/Documentation/networking/packet_mmap.txt b/Documentation/networking/packet_mmap.txt index a6d7cb91069e..daa015af16a0 100644 --- a/Documentation/networking/packet_mmap.txt +++ b/Documentation/networking/packet_mmap.txt @@ -440,9 +440,10 @@ and the following flags apply: +++ Capture process: from include/linux/if_packet.h - #define TP_STATUS_COPY 2 - #define TP_STATUS_LOSING 4 - #define TP_STATUS_CSUMNOTREADY 8 + #define TP_STATUS_COPY (1 << 1) + #define TP_STATUS_LOSING (1 << 2) + #define TP_STATUS_CSUMNOTREADY (1 << 3) + #define TP_STATUS_CSUM_VALID (1 << 7) TP_STATUS_COPY : This flag indicates that the frame (and associated meta information) has been truncated because it's @@ -466,6 +467,12 @@ TP_STATUS_CSUMNOTREADY: currently it's used for outgoing IP packets which reading the packet we should not try to check the checksum. +TP_STATUS_CSUM_VALID : This flag indicates that at least the transport + header checksum of the packet has been already + validated on the kernel side. If the flag is not set + then we are free to check the checksum by ourselves + provided that TP_STATUS_CSUMNOTREADY is also not set. + for convenience there are also the following defines: #define TP_STATUS_KERNEL 0 diff --git a/include/uapi/linux/if_packet.h b/include/uapi/linux/if_packet.h index da2d668b8cf1..053bd102fbe0 100644 --- a/include/uapi/linux/if_packet.h +++ b/include/uapi/linux/if_packet.h @@ -99,6 +99,7 @@ struct tpacket_auxdata { #define TP_STATUS_VLAN_VALID (1 << 4) /* auxdata has valid tp_vlan_tci */ #define TP_STATUS_BLK_TMO (1 << 5) #define TP_STATUS_VLAN_TPID_VALID (1 << 6) /* auxdata has valid tp_vlan_tpid */ +#define TP_STATUS_CSUM_VALID (1 << 7) /* Tx ring - header status */ #define TP_STATUS_AVAILABLE 0 diff --git a/net/packet/af_packet.c b/net/packet/af_packet.c index 9d854c5ce0b5..5102c3cc4eec 100644 --- a/net/packet/af_packet.c +++ b/net/packet/af_packet.c @@ -1924,6 +1924,10 @@ static int tpacket_rcv(struct sk_buff *skb, struct net_device *dev, if (skb->ip_summed == CHECKSUM_PARTIAL) status |= TP_STATUS_CSUMNOTREADY; + else if (skb->pkt_type != PACKET_OUTGOING && + (skb->ip_summed == CHECKSUM_COMPLETE || + skb_csum_unnecessary(skb))) + status |= TP_STATUS_CSUM_VALID; if (snaplen > res) snaplen = res; @@ -3031,6 +3035,11 @@ static int packet_recvmsg(struct socket *sock, struct msghdr *msg, size_t len, aux.tp_status = TP_STATUS_USER; if (skb->ip_summed == CHECKSUM_PARTIAL) aux.tp_status |= TP_STATUS_CSUMNOTREADY; + else if (skb->pkt_type != PACKET_OUTGOING && + (skb->ip_summed == CHECKSUM_COMPLETE || + skb_csum_unnecessary(skb))) + aux.tp_status |= TP_STATUS_CSUM_VALID; + aux.tp_len = origlen; aux.tp_snaplen = skb->len; aux.tp_mac = 0; |
