From 37dd0247797b168ad1cc7f5dbec825a1ee66535b Mon Sep 17 00:00:00 2001 From: Tom Herbert Date: Fri, 3 Oct 2014 15:48:09 -0700 Subject: [PATCH] gue: Receive side for Generic UDP Encapsulation This patch adds support receiving for GUE packets in the fou module. The fou module now supports direct foo-over-udp (no encapsulation header) and GUE. To support this a type parameter is added to the fou netlink parameters. For a GUE socket we define gue_udp_recv, gue_gro_receive, and gue_gro_complete to handle the specifics of the GUE protocol. Most of the code to manage and configure sockets is common with the fou. Signed-off-by: Tom Herbert Signed-off-by: David S. Miller --- include/net/gue.h | 23 +++++ include/uapi/linux/fou.h | 7 ++ net/ipv4/fou.c | 196 +++++++++++++++++++++++++++++++++++++-- 3 files changed, 217 insertions(+), 9 deletions(-) create mode 100644 include/net/gue.h diff --git a/include/net/gue.h b/include/net/gue.h new file mode 100644 index 000000000000..b6c332788084 --- /dev/null +++ b/include/net/gue.h @@ -0,0 +1,23 @@ +#ifndef __NET_GUE_H +#define __NET_GUE_H + +struct guehdr { + union { + struct { +#if defined(__LITTLE_ENDIAN_BITFIELD) + __u8 hlen:4, + version:4; +#elif defined (__BIG_ENDIAN_BITFIELD) + __u8 version:4, + hlen:4; +#else +#error "Please fix " +#endif + __u8 next_hdr; + __u16 flags; + }; + __u32 word; + }; +}; + +#endif diff --git a/include/uapi/linux/fou.h b/include/uapi/linux/fou.h index e03376de453d..8df06894da23 100644 --- a/include/uapi/linux/fou.h +++ b/include/uapi/linux/fou.h @@ -13,6 +13,7 @@ enum { FOU_ATTR_PORT, /* u16 */ FOU_ATTR_AF, /* u8 */ FOU_ATTR_IPPROTO, /* u8 */ + FOU_ATTR_TYPE, /* u8 */ __FOU_ATTR_MAX, }; @@ -27,6 +28,12 @@ enum { __FOU_CMD_MAX, }; +enum { + FOU_ENCAP_UNSPEC, + FOU_ENCAP_DIRECT, + FOU_ENCAP_GUE, +}; + #define FOU_CMD_MAX (__FOU_CMD_MAX - 1) #endif /* _UAPI_LINUX_FOU_H */ diff --git a/net/ipv4/fou.c b/net/ipv4/fou.c index 7e2126a31f2e..efa70ad44906 100644 --- a/net/ipv4/fou.c +++ b/net/ipv4/fou.c @@ -7,6 +7,7 @@ #include #include #include +#include #include #include #include @@ -27,6 +28,7 @@ struct fou { }; struct fou_cfg { + u16 type; u8 protocol; struct udp_port_cfg udp_config; }; @@ -64,6 +66,41 @@ static int fou_udp_recv(struct sock *sk, struct sk_buff *skb) sizeof(struct udphdr)); } +static int gue_udp_recv(struct sock *sk, struct sk_buff *skb) +{ + struct fou *fou = fou_from_sock(sk); + size_t len; + struct guehdr *guehdr; + struct udphdr *uh; + + if (!fou) + return 1; + + len = sizeof(struct udphdr) + sizeof(struct guehdr); + if (!pskb_may_pull(skb, len)) + goto drop; + + uh = udp_hdr(skb); + guehdr = (struct guehdr *)&uh[1]; + + len += guehdr->hlen << 2; + if (!pskb_may_pull(skb, len)) + goto drop; + + if (guehdr->version != 0) + goto drop; + + if (guehdr->flags) { + /* No support yet */ + goto drop; + } + + return fou_udp_encap_recv_deliver(skb, guehdr->next_hdr, len); +drop: + kfree_skb(skb); + return 0; +} + static struct sk_buff **fou_gro_receive(struct sk_buff **head, struct sk_buff *skb) { @@ -107,6 +144,112 @@ out_unlock: return err; } +static struct sk_buff **gue_gro_receive(struct sk_buff **head, + struct sk_buff *skb) +{ + const struct net_offload **offloads; + const struct net_offload *ops; + struct sk_buff **pp = NULL; + struct sk_buff *p; + u8 proto; + struct guehdr *guehdr; + unsigned int hlen, guehlen; + unsigned int off; + int flush = 1; + + off = skb_gro_offset(skb); + hlen = off + sizeof(*guehdr); + guehdr = skb_gro_header_fast(skb, off); + if (skb_gro_header_hard(skb, hlen)) { + guehdr = skb_gro_header_slow(skb, hlen, off); + if (unlikely(!guehdr)) + goto out; + } + + proto = guehdr->next_hdr; + + rcu_read_lock(); + offloads = NAPI_GRO_CB(skb)->is_ipv6 ? inet6_offloads : inet_offloads; + ops = rcu_dereference(offloads[proto]); + if (WARN_ON(!ops || !ops->callbacks.gro_receive)) + goto out_unlock; + + guehlen = sizeof(*guehdr) + (guehdr->hlen << 2); + + hlen = off + guehlen; + if (skb_gro_header_hard(skb, hlen)) { + guehdr = skb_gro_header_slow(skb, hlen, off); + if (unlikely(!guehdr)) + goto out_unlock; + } + + flush = 0; + + for (p = *head; p; p = p->next) { + const struct guehdr *guehdr2; + + if (!NAPI_GRO_CB(p)->same_flow) + continue; + + guehdr2 = (struct guehdr *)(p->data + off); + + /* Compare base GUE header to be equal (covers + * hlen, version, next_hdr, and flags. + */ + if (guehdr->word != guehdr2->word) { + NAPI_GRO_CB(p)->same_flow = 0; + continue; + } + + /* Compare optional fields are the same. */ + if (guehdr->hlen && memcmp(&guehdr[1], &guehdr2[1], + guehdr->hlen << 2)) { + NAPI_GRO_CB(p)->same_flow = 0; + continue; + } + } + + skb_gro_pull(skb, guehlen); + + /* Adjusted NAPI_GRO_CB(skb)->csum after skb_gro_pull()*/ + skb_gro_postpull_rcsum(skb, guehdr, guehlen); + + pp = ops->callbacks.gro_receive(head, skb); + +out_unlock: + rcu_read_unlock(); +out: + NAPI_GRO_CB(skb)->flush |= flush; + + return pp; +} + +static int gue_gro_complete(struct sk_buff *skb, int nhoff) +{ + const struct net_offload **offloads; + struct guehdr *guehdr = (struct guehdr *)(skb->data + nhoff); + const struct net_offload *ops; + unsigned int guehlen; + u8 proto; + int err = -ENOENT; + + proto = guehdr->next_hdr; + + guehlen = sizeof(*guehdr) + (guehdr->hlen << 2); + + rcu_read_lock(); + offloads = NAPI_GRO_CB(skb)->is_ipv6 ? inet6_offloads : inet_offloads; + ops = rcu_dereference(offloads[proto]); + if (WARN_ON(!ops || !ops->callbacks.gro_complete)) + goto out_unlock; + + err = ops->callbacks.gro_complete(skb, nhoff + guehlen); + +out_unlock: + rcu_read_unlock(); + return err; +} + static int fou_add_to_port_list(struct fou *fou) { struct fou *fout; @@ -142,6 +285,28 @@ static void fou_release(struct fou *fou) kfree(fou); } +static int fou_encap_init(struct sock *sk, struct fou *fou, struct fou_cfg *cfg) +{ + udp_sk(sk)->encap_rcv = fou_udp_recv; + fou->protocol = cfg->protocol; + fou->udp_offloads.callbacks.gro_receive = fou_gro_receive; + fou->udp_offloads.callbacks.gro_complete = fou_gro_complete; + fou->udp_offloads.port = cfg->udp_config.local_udp_port; + fou->udp_offloads.ipproto = cfg->protocol; + + return 0; +} + +static int gue_encap_init(struct sock *sk, struct fou *fou, struct fou_cfg *cfg) +{ + udp_sk(sk)->encap_rcv = gue_udp_recv; + fou->udp_offloads.callbacks.gro_receive = gue_gro_receive; + fou->udp_offloads.callbacks.gro_complete = gue_gro_complete; + fou->udp_offloads.port = cfg->udp_config.local_udp_port; + + return 0; +} + static int fou_create(struct net *net, struct fou_cfg *cfg, struct socket **sockp) { @@ -164,10 +329,24 @@ static int fou_create(struct net *net, struct fou_cfg *cfg, sk = sock->sk; - /* Mark socket as an encapsulation socket. See net/ipv4/udp.c */ - fou->protocol = cfg->protocol; - fou->port = cfg->udp_config.local_udp_port; - udp_sk(sk)->encap_rcv = fou_udp_recv; + fou->port = cfg->udp_config.local_udp_port; + + /* Initial for fou type */ + switch (cfg->type) { + case FOU_ENCAP_DIRECT: + err = fou_encap_init(sk, fou, cfg); + if (err) + goto error; + break; + case FOU_ENCAP_GUE: + err = gue_encap_init(sk, fou, cfg); + if (err) + goto error; + break; + default: + err = -EINVAL; + goto error; + } udp_sk(sk)->encap_type = 1; udp_encap_enable(); @@ -179,11 +358,6 @@ static int fou_create(struct net *net, struct fou_cfg *cfg, sk->sk_allocation = GFP_ATOMIC; - fou->udp_offloads.callbacks.gro_receive = fou_gro_receive; - fou->udp_offloads.callbacks.gro_complete = fou_gro_complete; - fou->udp_offloads.port = cfg->udp_config.local_udp_port; - fou->udp_offloads.ipproto = cfg->protocol; - if (cfg->udp_config.family == AF_INET) { err = udp_add_offload(&fou->udp_offloads); if (err) @@ -240,6 +414,7 @@ static struct nla_policy fou_nl_policy[FOU_ATTR_MAX + 1] = { [FOU_ATTR_PORT] = { .type = NLA_U16, }, [FOU_ATTR_AF] = { .type = NLA_U8, }, [FOU_ATTR_IPPROTO] = { .type = NLA_U8, }, + [FOU_ATTR_TYPE] = { .type = NLA_U8, }, }; static int parse_nl_config(struct genl_info *info, @@ -267,6 +442,9 @@ static int parse_nl_config(struct genl_info *info, if (info->attrs[FOU_ATTR_IPPROTO]) cfg->protocol = nla_get_u8(info->attrs[FOU_ATTR_IPPROTO]); + if (info->attrs[FOU_ATTR_TYPE]) + cfg->type = nla_get_u8(info->attrs[FOU_ATTR_TYPE]); + return 0; } -- 2.20.1