From: Gao Feng <f...@ikuai8.com> The PPTP is encapsulated by GRE header with that GRE_VERSION bits must contain one. But current GRE RPS needs the GRE_VERSION must be zero. So RPS does not work for PPTP traffic.
In my test environment, there are four MIPS cores, and all traffic are passed through by PPTP. As a result, only one core is 100% busy while other three cores are very idle. After this patch, the usage of four cores are balanced well. Signed-off-by: Gao Feng <f...@ikuai8.com> --- v3: 1) Move struct pptp_gre_header defination into new file pptp.h 2) Use sizeof GRE and PPTP type instead of literal value; 3) Remove strict flag check for PPTP to robust; 4) Consolidate the codes again; v2: Update according to Tom and Philp's advice. 1) Consolidate the codes with GRE version 0 path; 2) Use PPP_PROTOCOL to get ppp protol; 3) Set the FLOW_DIS_ENCAPSULATION flag; v1: Intial patch drivers/net/ppp/pptp.c | 36 +---------- include/net/pptp.h | 40 ++++++++++++ include/uapi/linux/if_tunnel.h | 7 +- net/core/flow_dissector.c | 141 +++++++++++++++++++++++++---------------- 4 files changed, 134 insertions(+), 90 deletions(-) create mode 100644 include/net/pptp.h diff --git a/drivers/net/ppp/pptp.c b/drivers/net/ppp/pptp.c index ae0905e..3e68dbc 100644 --- a/drivers/net/ppp/pptp.c +++ b/drivers/net/ppp/pptp.c @@ -37,6 +37,7 @@ #include <net/icmp.h> #include <net/route.h> #include <net/gre.h> +#include <net/pptp.h> #include <linux/uaccess.h> @@ -53,41 +54,6 @@ static struct proto pptp_sk_proto __read_mostly; static const struct ppp_channel_ops pptp_chan_ops; static const struct proto_ops pptp_ops; -#define PPP_LCP_ECHOREQ 0x09 -#define PPP_LCP_ECHOREP 0x0A -#define SC_RCV_BITS (SC_RCV_B7_1|SC_RCV_B7_0|SC_RCV_ODDP|SC_RCV_EVNP) - -#define MISSING_WINDOW 20 -#define WRAPPED(curseq, lastseq)\ - ((((curseq) & 0xffffff00) == 0) &&\ - (((lastseq) & 0xffffff00) == 0xffffff00)) - -#define PPTP_GRE_PROTO 0x880B -#define PPTP_GRE_VER 0x1 - -#define PPTP_GRE_FLAG_C 0x80 -#define PPTP_GRE_FLAG_R 0x40 -#define PPTP_GRE_FLAG_K 0x20 -#define PPTP_GRE_FLAG_S 0x10 -#define PPTP_GRE_FLAG_A 0x80 - -#define PPTP_GRE_IS_C(f) ((f)&PPTP_GRE_FLAG_C) -#define PPTP_GRE_IS_R(f) ((f)&PPTP_GRE_FLAG_R) -#define PPTP_GRE_IS_K(f) ((f)&PPTP_GRE_FLAG_K) -#define PPTP_GRE_IS_S(f) ((f)&PPTP_GRE_FLAG_S) -#define PPTP_GRE_IS_A(f) ((f)&PPTP_GRE_FLAG_A) - -#define PPTP_HEADER_OVERHEAD (2+sizeof(struct pptp_gre_header)) -struct pptp_gre_header { - u8 flags; - u8 ver; - __be16 protocol; - __be16 payload_len; - __be16 call_id; - __be32 seq; - __be32 ack; -} __packed; - static struct pppox_sock *lookup_chan(u16 call_id, __be32 s_addr) { struct pppox_sock *sock; diff --git a/include/net/pptp.h b/include/net/pptp.h new file mode 100644 index 0000000..301d3e2 --- /dev/null +++ b/include/net/pptp.h @@ -0,0 +1,40 @@ +#ifndef _NET_PPTP_H +#define _NET_PPTP_H + +#define PPP_LCP_ECHOREQ 0x09 +#define PPP_LCP_ECHOREP 0x0A +#define SC_RCV_BITS (SC_RCV_B7_1|SC_RCV_B7_0|SC_RCV_ODDP|SC_RCV_EVNP) + +#define MISSING_WINDOW 20 +#define WRAPPED(curseq, lastseq)\ + ((((curseq) & 0xffffff00) == 0) &&\ + (((lastseq) & 0xffffff00) == 0xffffff00)) + +#define PPTP_GRE_PROTO 0x880B +#define PPTP_GRE_VER 0x1 + +#define PPTP_GRE_FLAG_C 0x80 +#define PPTP_GRE_FLAG_R 0x40 +#define PPTP_GRE_FLAG_K 0x20 +#define PPTP_GRE_FLAG_S 0x10 +#define PPTP_GRE_FLAG_A 0x80 + +#define PPTP_GRE_IS_C(f) ((f)&PPTP_GRE_FLAG_C) +#define PPTP_GRE_IS_R(f) ((f)&PPTP_GRE_FLAG_R) +#define PPTP_GRE_IS_K(f) ((f)&PPTP_GRE_FLAG_K) +#define PPTP_GRE_IS_S(f) ((f)&PPTP_GRE_FLAG_S) +#define PPTP_GRE_IS_A(f) ((f)&PPTP_GRE_FLAG_A) + +#define PPTP_HEADER_OVERHEAD (2+sizeof(struct pptp_gre_header)) +struct pptp_gre_header { + u8 flags; + u8 ver; + __be16 protocol; + __be16 payload_len; + __be16 call_id; + __be32 seq; + __be32 ack; +} __packed; + + +#endif diff --git a/include/uapi/linux/if_tunnel.h b/include/uapi/linux/if_tunnel.h index 1046f55..7d889db 100644 --- a/include/uapi/linux/if_tunnel.h +++ b/include/uapi/linux/if_tunnel.h @@ -24,9 +24,14 @@ #define GRE_SEQ __cpu_to_be16(0x1000) #define GRE_STRICT __cpu_to_be16(0x0800) #define GRE_REC __cpu_to_be16(0x0700) -#define GRE_FLAGS __cpu_to_be16(0x00F8) +#define GRE_ACK __cpu_to_be16(0x0080) +#define GRE_FLAGS __cpu_to_be16(0x0078) #define GRE_VERSION __cpu_to_be16(0x0007) +#define GRE_VERSION_1 __cpu_to_be16(0x0001) +#define GRE_PROTO_PPP __cpu_to_be16(0x880b) + + struct ip_tunnel_parm { char name[IFNAMSIZ]; int link; diff --git a/net/core/flow_dissector.c b/net/core/flow_dissector.c index 61ad43f..52b7c3c 100644 --- a/net/core/flow_dissector.c +++ b/net/core/flow_dissector.c @@ -6,6 +6,8 @@ #include <linux/if_vlan.h> #include <net/ip.h> #include <net/ipv6.h> +#include <net/gre.h> +#include <net/pptp.h> #include <linux/igmp.h> #include <linux/icmp.h> #include <linux/sctp.h> @@ -338,71 +340,102 @@ mpls: ip_proto_again: switch (ip_proto) { case IPPROTO_GRE: { - struct gre_hdr { - __be16 flags; - __be16 proto; - } *hdr, _hdr; + struct gre_base_hdr *hdr, _hdr; hdr = __skb_header_pointer(skb, nhoff, sizeof(_hdr), data, hlen, &_hdr); if (!hdr) goto out_bad; - /* - * Only look inside GRE if version zero and no - * routing - */ - if (hdr->flags & (GRE_VERSION | GRE_ROUTING)) - break; - proto = hdr->proto; - nhoff += 4; - if (hdr->flags & GRE_CSUM) - nhoff += 4; - if (hdr->flags & GRE_KEY) { - const __be32 *keyid; - __be32 _keyid; + /* Only look inside GRE without routing */ + if (!(hdr->flags & GRE_ROUTING)) { + int offset = 0; - keyid = __skb_header_pointer(skb, nhoff, sizeof(_keyid), - data, hlen, &_keyid); + proto = hdr->protocol; - if (!keyid) - goto out_bad; + if (hdr->flags & GRE_VERSION) { + /* Maybe PPTP in GRE */ + if (!(proto == GRE_PROTO_PPP && (hdr->flags & GRE_KEY) && + (hdr->flags & GRE_VERSION) == GRE_VERSION_1)) + break; + } - if (dissector_uses_key(flow_dissector, - FLOW_DISSECTOR_KEY_GRE_KEYID)) { - key_keyid = skb_flow_dissector_target(flow_dissector, - FLOW_DISSECTOR_KEY_GRE_KEYID, - target_container); - key_keyid->keyid = *keyid; + offset += sizeof(struct gre_base_hdr); + + if (hdr->flags & GRE_CSUM) + offset += sizeof(__be32); + + if (hdr->flags & GRE_KEY) { + const __be32 *keyid; + __be32 _keyid; + + keyid = __skb_header_pointer(skb, nhoff + offset, sizeof(_keyid), + data, hlen, &_keyid); + + if (!keyid) + goto out_bad; + + if (dissector_uses_key(flow_dissector, + FLOW_DISSECTOR_KEY_GRE_KEYID)) { + key_keyid = skb_flow_dissector_target(flow_dissector, + FLOW_DISSECTOR_KEY_GRE_KEYID, + target_container); + key_keyid->keyid = *keyid; + } + offset += sizeof(_keyid); } - nhoff += 4; - } - if (hdr->flags & GRE_SEQ) - nhoff += 4; - if (proto == htons(ETH_P_TEB)) { - const struct ethhdr *eth; - struct ethhdr _eth; - - eth = __skb_header_pointer(skb, nhoff, - sizeof(_eth), - data, hlen, &_eth); - if (!eth) - goto out_bad; - proto = eth->h_proto; - nhoff += sizeof(*eth); - - /* Cap headers that we access via pointers at the - * end of the Ethernet header as our maximum alignment - * at that point is only 2 bytes. - */ - if (NET_IP_ALIGN) - hlen = nhoff; - } - key_control->flags |= FLOW_DIS_ENCAPSULATION; - if (flags & FLOW_DISSECTOR_F_STOP_AT_ENCAP) - goto out_good; + if (hdr->flags & GRE_SEQ) + offset += sizeof(((struct pptp_gre_header *)0)->seq); + + if (hdr->flags & GRE_ACK) + offset += sizeof(((struct pptp_gre_header *)0)->ack); + + if (proto == GRE_PROTO_PPP) { + u8 _ppp_hdr[PPP_HDRLEN]; + u8 *ppp_hdr; + + ppp_hdr = skb_header_pointer(skb, nhoff + offset, + sizeof(_ppp_hdr), _ppp_hdr); + if (!ppp_hdr) + goto out_bad; + + proto = PPP_PROTOCOL(ppp_hdr); + if (proto == PPP_IP) + proto = htons(ETH_P_IP); + else if (proto == PPP_IPV6) + proto = htons(ETH_P_IPV6); + else + break; + + offset += PPP_HDRLEN; + } else if (proto == htons(ETH_P_TEB)) { + const struct ethhdr *eth; + struct ethhdr _eth; + + eth = __skb_header_pointer(skb, nhoff + offset, + sizeof(_eth), + data, hlen, &_eth); + if (!eth) + goto out_bad; + proto = eth->h_proto; + offset += sizeof(*eth); + + /* Cap headers that we access via pointers at the + * end of the Ethernet header as our maximum alignment + * at that point is only 2 bytes. + */ + if (NET_IP_ALIGN) + hlen = (nhoff + offset); + } - goto again; + nhoff += offset; + key_control->flags |= FLOW_DIS_ENCAPSULATION; + if (flags & FLOW_DISSECTOR_F_STOP_AT_ENCAP) + goto out_good; + + goto again; + } + break; } case NEXTHDR_HOP: case NEXTHDR_ROUTING: -- 1.9.1