Message ID | 1588694706-26433-1-git-send-email-u9012063@gmail.com |
---|---|
State | Accepted |
Delegated to: | David Miller |
Headers | show |
Series | [PATCHv2] erspan: Add type I version 0 support. | expand |
From: William Tu <u9012063@gmail.com> Date: Tue, 5 May 2020 09:05:06 -0700 > > The Type I ERSPAN frame format is based on the barebones > IP + GRE(4-byte) encapsulation on top of the raw mirrored frame. > Both type I and II use 0x88BE as protocol type. Unlike type II > and III, no sequence number or key is required. > To creat a type I erspan tunnel device: > $ ip link add dev erspan11 type erspan \ > local 172.16.1.100 remote 172.16.1.200 \ > erspan_ver 0 > > Signed-off-by: William Tu <u9012063@gmail.com> Applied to net-next, thanks.
On 5/5/20 9:05 AM, William Tu wrote: > The Type I ERSPAN frame format is based on the barebones > IP + GRE(4-byte) encapsulation on top of the raw mirrored frame. > Both type I and II use 0x88BE as protocol type. Unlike type II > and III, no sequence number or key is required. > To creat a type I erspan tunnel device: > $ ip link add dev erspan11 type erspan \ > local 172.16.1.100 remote 172.16.1.200 \ > erspan_ver 0 > > Signed-off-by: William Tu <u9012063@gmail.com> > --- > v2: > remove the inline keyword, let compiler decide. > v1: > I didn't notice there is Type I when I did first erspan implementation > because it is not in the ietf draft 00 and 01. It's until recently I got > request for adding type I. Spec is below at draft 02: > https://tools.ietf.org/html/draft-foschiano-erspan-02#section-4.1 > > To verify with Wireshark, make sure you have: > commit ef76d65fc61d01c2ce5184140f4b1bba0019078b > Author: Guy Harris <guy@alum.mit.edu> > Date: Mon Sep 30 16:35:35 2019 -0700 > > Fix checks for "do we have an ERSPAN header?" > --- > include/net/erspan.h | 19 +++++++++++++++-- > net/ipv4/ip_gre.c | 58 ++++++++++++++++++++++++++++++++++++++-------------- > 2 files changed, 60 insertions(+), 17 deletions(-) > > diff --git a/include/net/erspan.h b/include/net/erspan.h > index b39643ef4c95..0d9e86bd9893 100644 > --- a/include/net/erspan.h > +++ b/include/net/erspan.h > @@ -2,7 +2,19 @@ > #define __LINUX_ERSPAN_H > > /* > - * GRE header for ERSPAN encapsulation (8 octets [34:41]) -- 8 bytes > + * GRE header for ERSPAN type I encapsulation (4 octets [34:37]) > + * 0 1 2 3 > + * 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 > + * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ > + * |0|0|0|0|0|00000|000000000|00000| Protocol Type for ERSPAN | > + * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ > + * > + * The Type I ERSPAN frame format is based on the barebones IP + GRE > + * encapsulation (as described above) on top of the raw mirrored frame. > + * There is no extra ERSPAN header. > + * > + * > + * GRE header for ERSPAN type II and II encapsulation (8 octets [34:41]) > * 0 1 2 3 > * 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 > * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ > @@ -43,7 +55,7 @@ > * | Platform Specific Info | > * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ > * > - * GRE proto ERSPAN type II = 0x88BE, type III = 0x22EB > + * GRE proto ERSPAN type I/II = 0x88BE, type III = 0x22EB > */ > > #include <uapi/linux/erspan.h> > @@ -139,6 +151,9 @@ static inline u8 get_hwid(const struct erspan_md2 *md2) > > static inline int erspan_hdr_len(int version) > { > + if (version == 0) > + return 0; > + > return sizeof(struct erspan_base_hdr) + > (version == 1 ? ERSPAN_V1_MDSIZE : ERSPAN_V2_MDSIZE); > } > diff --git a/net/ipv4/ip_gre.c b/net/ipv4/ip_gre.c > index 029b24eeafba..e29cd48674d7 100644 > --- a/net/ipv4/ip_gre.c > +++ b/net/ipv4/ip_gre.c > @@ -248,6 +248,15 @@ static void gre_err(struct sk_buff *skb, u32 info) > ipgre_err(skb, info, &tpi); > } > > +static bool is_erspan_type1(int gre_hdr_len) > +{ > + /* Both ERSPAN type I (version 0) and type II (version 1) use > + * protocol 0x88BE, but the type I has only 4-byte GRE header, > + * while type II has 8-byte. > + */ > + return gre_hdr_len == 4; > +} > + > static int erspan_rcv(struct sk_buff *skb, struct tnl_ptk_info *tpi, > int gre_hdr_len) > { > @@ -262,17 +271,26 @@ static int erspan_rcv(struct sk_buff *skb, struct tnl_ptk_info *tpi, > int len; > > itn = net_generic(net, erspan_net_id); > - > iph = ip_hdr(skb); > - ershdr = (struct erspan_base_hdr *)(skb->data + gre_hdr_len); > - ver = ershdr->ver; > - > - tunnel = ip_tunnel_lookup(itn, skb->dev->ifindex, > - tpi->flags | TUNNEL_KEY, > - iph->saddr, iph->daddr, tpi->key); > + if (is_erspan_type1(gre_hdr_len)) { > + ver = 0; > + tunnel = ip_tunnel_lookup(itn, skb->dev->ifindex, > + tpi->flags | TUNNEL_NO_KEY, > + iph->saddr, iph->daddr, 0); > + } else { > + ershdr = (struct erspan_base_hdr *)(skb->data + gre_hdr_len); > + ver = ershdr->ver; > + tunnel = ip_tunnel_lookup(itn, skb->dev->ifindex, > + tpi->flags | TUNNEL_KEY, > + iph->saddr, iph->daddr, tpi->key); > + } > > if (tunnel) { > - len = gre_hdr_len + erspan_hdr_len(ver); > + if (is_erspan_type1(gre_hdr_len)) > + len = gre_hdr_len; > + else > + len = gre_hdr_len + erspan_hdr_len(ver); > + > if (unlikely(!pskb_may_pull(skb, len))) > return PACKET_REJECT; > > @@ -665,7 +683,10 @@ static netdev_tx_t erspan_xmit(struct sk_buff *skb, > } > > /* Push ERSPAN header */ > - if (tunnel->erspan_ver == 1) { > + if (tunnel->erspan_ver == 0) { > + proto = htons(ETH_P_ERSPAN); > + tunnel->parms.o_flags &= ~TUNNEL_SEQ; > + } else if (tunnel->erspan_ver == 1) { > erspan_build_header(skb, ntohl(tunnel->parms.o_key), > tunnel->index, > truncate, true); > @@ -1066,7 +1087,10 @@ static int erspan_validate(struct nlattr *tb[], struct nlattr *data[], > if (ret) > return ret; > > - /* ERSPAN should only have GRE sequence and key flag */ > + if (nla_get_u8(data[IFLA_GRE_ERSPAN_VER]) == 0) I do not see anything in the code making sure IFLA_GRE_ERSPAN_VER has been provided by the user ? > + return 0; > + > + /* ERSPAN type II/III should only have GRE sequence and key flag */ > if (data[IFLA_GRE_OFLAGS]) > flags |= nla_get_be16(data[IFLA_GRE_OFLAGS]); > if (data[IFLA_GRE_IFLAGS]) > @@ -1174,7 +1198,7 @@ static int erspan_netlink_parms(struct net_device *dev, > if (data[IFLA_GRE_ERSPAN_VER]) { > t->erspan_ver = nla_get_u8(data[IFLA_GRE_ERSPAN_VER]); > > - if (t->erspan_ver != 1 && t->erspan_ver != 2) > + if (t->erspan_ver > 2) > return -EINVAL; > } > > @@ -1259,7 +1283,11 @@ static int erspan_tunnel_init(struct net_device *dev) > { > struct ip_tunnel *tunnel = netdev_priv(dev); > > - tunnel->tun_hlen = 8; > + if (tunnel->erspan_ver == 0) > + tunnel->tun_hlen = 4; /* 4-byte GRE hdr. */ > + else > + tunnel->tun_hlen = 8; /* 8-byte GRE hdr. */ > + > tunnel->parms.iph.protocol = IPPROTO_GRE; > tunnel->hlen = tunnel->tun_hlen + tunnel->encap_hlen + > erspan_hdr_len(tunnel->erspan_ver); > @@ -1456,8 +1484,8 @@ static int ipgre_fill_info(struct sk_buff *skb, const struct net_device *dev) > struct ip_tunnel_parm *p = &t->parms; > __be16 o_flags = p->o_flags; > > - if (t->erspan_ver == 1 || t->erspan_ver == 2) { > - if (!t->collect_md) > + if (t->erspan_ver <= 2) { > + if (t->erspan_ver != 0 && !t->collect_md) > o_flags |= TUNNEL_KEY; > > if (nla_put_u8(skb, IFLA_GRE_ERSPAN_VER, t->erspan_ver)) > @@ -1466,7 +1494,7 @@ static int ipgre_fill_info(struct sk_buff *skb, const struct net_device *dev) > if (t->erspan_ver == 1) { > if (nla_put_u32(skb, IFLA_GRE_ERSPAN_INDEX, t->index)) > goto nla_put_failure; > - } else { > + } else if (t->erspan_ver == 2) { > if (nla_put_u8(skb, IFLA_GRE_ERSPAN_DIR, t->dir)) > goto nla_put_failure; > if (nla_put_u16(skb, IFLA_GRE_ERSPAN_HWID, t->hwid)) >
On Wed, May 6, 2020 at 7:42 PM Eric Dumazet <eric.dumazet@gmail.com> wrote: > > > > On 5/5/20 9:05 AM, William Tu wrote: > > The Type I ERSPAN frame format is based on the barebones > > IP + GRE(4-byte) encapsulation on top of the raw mirrored frame. > > Both type I and II use 0x88BE as protocol type. Unlike type II > > and III, no sequence number or key is required. > > To creat a type I erspan tunnel device: > > $ ip link add dev erspan11 type erspan \ > > local 172.16.1.100 remote 172.16.1.200 \ > > erspan_ver 0 > > > > Signed-off-by: William Tu <u9012063@gmail.com> > > --- > > v2: > > remove the inline keyword, let compiler decide. > > v1: > > I didn't notice there is Type I when I did first erspan implementation > > because it is not in the ietf draft 00 and 01. It's until recently I got > > request for adding type I. Spec is below at draft 02: > > https://tools.ietf.org/html/draft-foschiano-erspan-02#section-4.1 > > > > To verify with Wireshark, make sure you have: > > commit ef76d65fc61d01c2ce5184140f4b1bba0019078b > > Author: Guy Harris <guy@alum.mit.edu> > > Date: Mon Sep 30 16:35:35 2019 -0700 > > > > Fix checks for "do we have an ERSPAN header?" > > --- > > include/net/erspan.h | 19 +++++++++++++++-- > > net/ipv4/ip_gre.c | 58 ++++++++++++++++++++++++++++++++++++++-------------- > > 2 files changed, 60 insertions(+), 17 deletions(-) > > > > diff --git a/include/net/erspan.h b/include/net/erspan.h > > index b39643ef4c95..0d9e86bd9893 100644 > > --- a/include/net/erspan.h > > +++ b/include/net/erspan.h > > @@ -2,7 +2,19 @@ > > #define __LINUX_ERSPAN_H > > > > /* > > - * GRE header for ERSPAN encapsulation (8 octets [34:41]) -- 8 bytes > > + * GRE header for ERSPAN type I encapsulation (4 octets [34:37]) > > + * 0 1 2 3 > > + * 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 > > + * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ > > + * |0|0|0|0|0|00000|000000000|00000| Protocol Type for ERSPAN | > > + * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ > > + * > > + * The Type I ERSPAN frame format is based on the barebones IP + GRE > > + * encapsulation (as described above) on top of the raw mirrored frame. > > + * There is no extra ERSPAN header. > > + * > > + * > > + * GRE header for ERSPAN type II and II encapsulation (8 octets [34:41]) > > * 0 1 2 3 > > * 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 > > * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ > > @@ -43,7 +55,7 @@ > > * | Platform Specific Info | > > * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ > > * > > - * GRE proto ERSPAN type II = 0x88BE, type III = 0x22EB > > + * GRE proto ERSPAN type I/II = 0x88BE, type III = 0x22EB > > */ > > > > #include <uapi/linux/erspan.h> > > @@ -139,6 +151,9 @@ static inline u8 get_hwid(const struct erspan_md2 *md2) > > > > static inline int erspan_hdr_len(int version) > > { > > + if (version == 0) > > + return 0; > > + > > return sizeof(struct erspan_base_hdr) + > > (version == 1 ? ERSPAN_V1_MDSIZE : ERSPAN_V2_MDSIZE); > > } > > diff --git a/net/ipv4/ip_gre.c b/net/ipv4/ip_gre.c > > index 029b24eeafba..e29cd48674d7 100644 > > --- a/net/ipv4/ip_gre.c > > +++ b/net/ipv4/ip_gre.c > > @@ -248,6 +248,15 @@ static void gre_err(struct sk_buff *skb, u32 info) > > ipgre_err(skb, info, &tpi); > > } > > > > +static bool is_erspan_type1(int gre_hdr_len) > > +{ > > + /* Both ERSPAN type I (version 0) and type II (version 1) use > > + * protocol 0x88BE, but the type I has only 4-byte GRE header, > > + * while type II has 8-byte. > > + */ > > + return gre_hdr_len == 4; > > +} > > + > > static int erspan_rcv(struct sk_buff *skb, struct tnl_ptk_info *tpi, > > int gre_hdr_len) > > { > > @@ -262,17 +271,26 @@ static int erspan_rcv(struct sk_buff *skb, struct tnl_ptk_info *tpi, > > int len; > > > > itn = net_generic(net, erspan_net_id); > > - > > iph = ip_hdr(skb); > > - ershdr = (struct erspan_base_hdr *)(skb->data + gre_hdr_len); > > - ver = ershdr->ver; > > - > > - tunnel = ip_tunnel_lookup(itn, skb->dev->ifindex, > > - tpi->flags | TUNNEL_KEY, > > - iph->saddr, iph->daddr, tpi->key); > > + if (is_erspan_type1(gre_hdr_len)) { > > + ver = 0; > > + tunnel = ip_tunnel_lookup(itn, skb->dev->ifindex, > > + tpi->flags | TUNNEL_NO_KEY, > > + iph->saddr, iph->daddr, 0); > > + } else { > > + ershdr = (struct erspan_base_hdr *)(skb->data + gre_hdr_len); > > + ver = ershdr->ver; > > + tunnel = ip_tunnel_lookup(itn, skb->dev->ifindex, > > + tpi->flags | TUNNEL_KEY, > > + iph->saddr, iph->daddr, tpi->key); > > + } > > > > if (tunnel) { > > - len = gre_hdr_len + erspan_hdr_len(ver); > > + if (is_erspan_type1(gre_hdr_len)) > > + len = gre_hdr_len; > > + else > > + len = gre_hdr_len + erspan_hdr_len(ver); > > + > > if (unlikely(!pskb_may_pull(skb, len))) > > return PACKET_REJECT; > > > > @@ -665,7 +683,10 @@ static netdev_tx_t erspan_xmit(struct sk_buff *skb, > > } > > > > /* Push ERSPAN header */ > > - if (tunnel->erspan_ver == 1) { > > + if (tunnel->erspan_ver == 0) { > > + proto = htons(ETH_P_ERSPAN); > > + tunnel->parms.o_flags &= ~TUNNEL_SEQ; > > + } else if (tunnel->erspan_ver == 1) { > > erspan_build_header(skb, ntohl(tunnel->parms.o_key), > > tunnel->index, > > truncate, true); > > @@ -1066,7 +1087,10 @@ static int erspan_validate(struct nlattr *tb[], struct nlattr *data[], > > if (ret) > > return ret; > > > > - /* ERSPAN should only have GRE sequence and key flag */ > > + if (nla_get_u8(data[IFLA_GRE_ERSPAN_VER]) == 0) > > I do not see anything in the code making sure IFLA_GRE_ERSPAN_VER has been provided by the user ? > Hi Eric, Thanks! at the iproute2 we always set the IFLA_GRE_ERSPAN_VER to 1 as default when user doesn't specify. But I should also make sure it is checked here for non-iproute2 users. If I understand correctly, I should add --- a/net/ipv4/ip_gre.c +++ b/net/ipv4/ip_gre.c @@ -1087,7 +1087,7 @@ static int erspan_validate(struct nlattr *tb[], struct nlattr *data[], if (ret) return ret; - if (nla_get_u8(data[IFLA_GRE_ERSPAN_VER]) == 0) + if (data[IFLA_GRE_ERSPAN_VER] && nla_get_u8(data[IFLA_GRE_ERSPAN_VER]) == 0) return 0; /* ERSPAN type II/III should only have GRE sequence and key flag */ Regards, William
diff --git a/include/net/erspan.h b/include/net/erspan.h index b39643ef4c95..0d9e86bd9893 100644 --- a/include/net/erspan.h +++ b/include/net/erspan.h @@ -2,7 +2,19 @@ #define __LINUX_ERSPAN_H /* - * GRE header for ERSPAN encapsulation (8 octets [34:41]) -- 8 bytes + * GRE header for ERSPAN type I encapsulation (4 octets [34:37]) + * 0 1 2 3 + * 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 + * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ + * |0|0|0|0|0|00000|000000000|00000| Protocol Type for ERSPAN | + * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ + * + * The Type I ERSPAN frame format is based on the barebones IP + GRE + * encapsulation (as described above) on top of the raw mirrored frame. + * There is no extra ERSPAN header. + * + * + * GRE header for ERSPAN type II and II encapsulation (8 octets [34:41]) * 0 1 2 3 * 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ @@ -43,7 +55,7 @@ * | Platform Specific Info | * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ * - * GRE proto ERSPAN type II = 0x88BE, type III = 0x22EB + * GRE proto ERSPAN type I/II = 0x88BE, type III = 0x22EB */ #include <uapi/linux/erspan.h> @@ -139,6 +151,9 @@ static inline u8 get_hwid(const struct erspan_md2 *md2) static inline int erspan_hdr_len(int version) { + if (version == 0) + return 0; + return sizeof(struct erspan_base_hdr) + (version == 1 ? ERSPAN_V1_MDSIZE : ERSPAN_V2_MDSIZE); } diff --git a/net/ipv4/ip_gre.c b/net/ipv4/ip_gre.c index 029b24eeafba..e29cd48674d7 100644 --- a/net/ipv4/ip_gre.c +++ b/net/ipv4/ip_gre.c @@ -248,6 +248,15 @@ static void gre_err(struct sk_buff *skb, u32 info) ipgre_err(skb, info, &tpi); } +static bool is_erspan_type1(int gre_hdr_len) +{ + /* Both ERSPAN type I (version 0) and type II (version 1) use + * protocol 0x88BE, but the type I has only 4-byte GRE header, + * while type II has 8-byte. + */ + return gre_hdr_len == 4; +} + static int erspan_rcv(struct sk_buff *skb, struct tnl_ptk_info *tpi, int gre_hdr_len) { @@ -262,17 +271,26 @@ static int erspan_rcv(struct sk_buff *skb, struct tnl_ptk_info *tpi, int len; itn = net_generic(net, erspan_net_id); - iph = ip_hdr(skb); - ershdr = (struct erspan_base_hdr *)(skb->data + gre_hdr_len); - ver = ershdr->ver; - - tunnel = ip_tunnel_lookup(itn, skb->dev->ifindex, - tpi->flags | TUNNEL_KEY, - iph->saddr, iph->daddr, tpi->key); + if (is_erspan_type1(gre_hdr_len)) { + ver = 0; + tunnel = ip_tunnel_lookup(itn, skb->dev->ifindex, + tpi->flags | TUNNEL_NO_KEY, + iph->saddr, iph->daddr, 0); + } else { + ershdr = (struct erspan_base_hdr *)(skb->data + gre_hdr_len); + ver = ershdr->ver; + tunnel = ip_tunnel_lookup(itn, skb->dev->ifindex, + tpi->flags | TUNNEL_KEY, + iph->saddr, iph->daddr, tpi->key); + } if (tunnel) { - len = gre_hdr_len + erspan_hdr_len(ver); + if (is_erspan_type1(gre_hdr_len)) + len = gre_hdr_len; + else + len = gre_hdr_len + erspan_hdr_len(ver); + if (unlikely(!pskb_may_pull(skb, len))) return PACKET_REJECT; @@ -665,7 +683,10 @@ static netdev_tx_t erspan_xmit(struct sk_buff *skb, } /* Push ERSPAN header */ - if (tunnel->erspan_ver == 1) { + if (tunnel->erspan_ver == 0) { + proto = htons(ETH_P_ERSPAN); + tunnel->parms.o_flags &= ~TUNNEL_SEQ; + } else if (tunnel->erspan_ver == 1) { erspan_build_header(skb, ntohl(tunnel->parms.o_key), tunnel->index, truncate, true); @@ -1066,7 +1087,10 @@ static int erspan_validate(struct nlattr *tb[], struct nlattr *data[], if (ret) return ret; - /* ERSPAN should only have GRE sequence and key flag */ + if (nla_get_u8(data[IFLA_GRE_ERSPAN_VER]) == 0) + return 0; + + /* ERSPAN type II/III should only have GRE sequence and key flag */ if (data[IFLA_GRE_OFLAGS]) flags |= nla_get_be16(data[IFLA_GRE_OFLAGS]); if (data[IFLA_GRE_IFLAGS]) @@ -1174,7 +1198,7 @@ static int erspan_netlink_parms(struct net_device *dev, if (data[IFLA_GRE_ERSPAN_VER]) { t->erspan_ver = nla_get_u8(data[IFLA_GRE_ERSPAN_VER]); - if (t->erspan_ver != 1 && t->erspan_ver != 2) + if (t->erspan_ver > 2) return -EINVAL; } @@ -1259,7 +1283,11 @@ static int erspan_tunnel_init(struct net_device *dev) { struct ip_tunnel *tunnel = netdev_priv(dev); - tunnel->tun_hlen = 8; + if (tunnel->erspan_ver == 0) + tunnel->tun_hlen = 4; /* 4-byte GRE hdr. */ + else + tunnel->tun_hlen = 8; /* 8-byte GRE hdr. */ + tunnel->parms.iph.protocol = IPPROTO_GRE; tunnel->hlen = tunnel->tun_hlen + tunnel->encap_hlen + erspan_hdr_len(tunnel->erspan_ver); @@ -1456,8 +1484,8 @@ static int ipgre_fill_info(struct sk_buff *skb, const struct net_device *dev) struct ip_tunnel_parm *p = &t->parms; __be16 o_flags = p->o_flags; - if (t->erspan_ver == 1 || t->erspan_ver == 2) { - if (!t->collect_md) + if (t->erspan_ver <= 2) { + if (t->erspan_ver != 0 && !t->collect_md) o_flags |= TUNNEL_KEY; if (nla_put_u8(skb, IFLA_GRE_ERSPAN_VER, t->erspan_ver)) @@ -1466,7 +1494,7 @@ static int ipgre_fill_info(struct sk_buff *skb, const struct net_device *dev) if (t->erspan_ver == 1) { if (nla_put_u32(skb, IFLA_GRE_ERSPAN_INDEX, t->index)) goto nla_put_failure; - } else { + } else if (t->erspan_ver == 2) { if (nla_put_u8(skb, IFLA_GRE_ERSPAN_DIR, t->dir)) goto nla_put_failure; if (nla_put_u16(skb, IFLA_GRE_ERSPAN_HWID, t->hwid))
The Type I ERSPAN frame format is based on the barebones IP + GRE(4-byte) encapsulation on top of the raw mirrored frame. Both type I and II use 0x88BE as protocol type. Unlike type II and III, no sequence number or key is required. To creat a type I erspan tunnel device: $ ip link add dev erspan11 type erspan \ local 172.16.1.100 remote 172.16.1.200 \ erspan_ver 0 Signed-off-by: William Tu <u9012063@gmail.com> --- v2: remove the inline keyword, let compiler decide. v1: I didn't notice there is Type I when I did first erspan implementation because it is not in the ietf draft 00 and 01. It's until recently I got request for adding type I. Spec is below at draft 02: https://tools.ietf.org/html/draft-foschiano-erspan-02#section-4.1 To verify with Wireshark, make sure you have: commit ef76d65fc61d01c2ce5184140f4b1bba0019078b Author: Guy Harris <guy@alum.mit.edu> Date: Mon Sep 30 16:35:35 2019 -0700 Fix checks for "do we have an ERSPAN header?" --- include/net/erspan.h | 19 +++++++++++++++-- net/ipv4/ip_gre.c | 58 ++++++++++++++++++++++++++++++++++++++-------------- 2 files changed, 60 insertions(+), 17 deletions(-)