Something went wrong. Try again.
(I'm so sorry!) Linux kernel mirror (for testing) git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git
Something went wrong. Try again.
C
123456789101112131415161718192021222324252627282930313233343536373839404142434445464748495051525354555657585960616263646566676869707172737475767778798081828384858687888990919293949596979899100101102103104105106107108109110111112113114115116117118119120121122123124125126127128129130131132133134135136137138139140141142143144145146147148149150151152153154155156157158159160161162163164165166167168169170171172173174175176177178179180181182183184185186187188189190191192193194195196197198199200201202203204205206207208209210211212213214215216217218219220221222223224225226227228229230231232233234235236237238239240241242243244245246247248249250251252253254255256257258259260261262263264265266267268269270271272273274275276277278279280281282283284285286287288289290291292293294295296297298299300301302303304305306307308309310311312313314315316317318319320321322323324325326327328329330331332333334335336337338339340341342343344345346347348349350351352353354355356357358359360361362363364365366367368369370371372373374375376377378379380381382383384385386387388389390391392393394395396397398399400401402403404405406407408409410411412413414415416417418419420421422423424425426427428429430431432433434435436437438439440441442443444445446447448449450451452453454455456457458459460461462463464465466467468469470471472/* SPDX-License-Identifier: GPL-2.0 */#ifndef _LINUX_VIRTIO_NET_H#define _LINUX_VIRTIO_NET_H
#include <linux/if_vlan.h>#include <linux/ip.h>#include <linux/ipv6.h>#include <linux/udp.h>#include <net/tcp.h>#include <uapi/linux/tcp.h>#include <uapi/linux/virtio_net.h>
static inline bool virtio_net_hdr_match_proto(__be16 protocol, __u8 gso_type){ switch (gso_type & ~VIRTIO_NET_HDR_GSO_ECN) { case VIRTIO_NET_HDR_GSO_TCPV4: return protocol == cpu_to_be16(ETH_P_IP); case VIRTIO_NET_HDR_GSO_TCPV6: return protocol == cpu_to_be16(ETH_P_IPV6); case VIRTIO_NET_HDR_GSO_UDP: case VIRTIO_NET_HDR_GSO_UDP_L4: return protocol == cpu_to_be16(ETH_P_IP) || protocol == cpu_to_be16(ETH_P_IPV6); default: return false; }}
static inline int virtio_net_hdr_set_proto(struct sk_buff *skb, const struct virtio_net_hdr *hdr){ if (skb->protocol) return 0;
switch (hdr->gso_type & ~VIRTIO_NET_HDR_GSO_ECN) { case VIRTIO_NET_HDR_GSO_TCPV4: case VIRTIO_NET_HDR_GSO_UDP: case VIRTIO_NET_HDR_GSO_UDP_L4: skb->protocol = cpu_to_be16(ETH_P_IP); break; case VIRTIO_NET_HDR_GSO_TCPV6: skb->protocol = cpu_to_be16(ETH_P_IPV6); break; default: return -EINVAL; }
return 0;}
static inline int __virtio_net_hdr_to_skb(struct sk_buff *skb, const struct virtio_net_hdr *hdr, bool little_endian, u8 hdr_gso_type){ unsigned int nh_min_len = sizeof(struct iphdr); unsigned int gso_type = 0; unsigned int thlen = 0; unsigned int p_off = 0; unsigned int ip_proto;
if (hdr_gso_type != VIRTIO_NET_HDR_GSO_NONE) { switch (hdr_gso_type & ~VIRTIO_NET_HDR_GSO_ECN) { case VIRTIO_NET_HDR_GSO_TCPV4: gso_type = SKB_GSO_TCPV4; ip_proto = IPPROTO_TCP; thlen = sizeof(struct tcphdr); break; case VIRTIO_NET_HDR_GSO_TCPV6: gso_type = SKB_GSO_TCPV6; ip_proto = IPPROTO_TCP; thlen = sizeof(struct tcphdr); nh_min_len = sizeof(struct ipv6hdr); break; case VIRTIO_NET_HDR_GSO_UDP: gso_type = SKB_GSO_UDP; ip_proto = IPPROTO_UDP; thlen = sizeof(struct udphdr); break; case VIRTIO_NET_HDR_GSO_UDP_L4: gso_type = SKB_GSO_UDP_L4; ip_proto = IPPROTO_UDP; thlen = sizeof(struct udphdr); break; default: return -EINVAL; }
if (hdr_gso_type & VIRTIO_NET_HDR_GSO_ECN) gso_type |= SKB_GSO_TCP_ECN;
if (hdr->gso_size == 0) return -EINVAL; }
skb_reset_mac_header(skb);
if (hdr->flags & VIRTIO_NET_HDR_F_NEEDS_CSUM) { u32 start = __virtio16_to_cpu(little_endian, hdr->csum_start); u32 off = __virtio16_to_cpu(little_endian, hdr->csum_offset); u32 needed = start + max_t(u32, thlen, off + sizeof(__sum16));
if (!pskb_may_pull(skb, needed)) return -EINVAL;
if (!skb_partial_csum_set(skb, start, off)) return -EINVAL; if (skb_transport_offset(skb) < nh_min_len) return -EINVAL;
nh_min_len = skb_transport_offset(skb); p_off = nh_min_len + thlen; if (!pskb_may_pull(skb, p_off)) return -EINVAL; } else if (gso_type) { /* gso packets without NEEDS_CSUM do not set transport_offset. * probe and drop if does not match one of the above types. */ struct flow_keys_basic keys;
if (!skb->protocol) { skb->protocol = dev_parse_header_protocol(skb); if (!skb->protocol) virtio_net_hdr_set_proto(skb, hdr); }retry: if (!skb_flow_dissect_flow_keys_basic(NULL, skb, &keys, NULL, 0, 0, 0, 0)) { /* UFO does not specify ipv4 or 6: try both */ if (gso_type & SKB_GSO_UDP && skb->protocol == htons(ETH_P_IP)) { skb->protocol = htons(ETH_P_IPV6); goto retry; } return -EINVAL; }
p_off = keys.control.thoff + thlen; if (!pskb_may_pull(skb, p_off) || keys.basic.ip_proto != ip_proto || !virtio_net_hdr_match_proto(keys.basic.n_proto, hdr_gso_type)) return -EINVAL;
skb_set_transport_header(skb, keys.control.thoff); }
if (hdr_gso_type != VIRTIO_NET_HDR_GSO_NONE) { u16 gso_size = __virtio16_to_cpu(little_endian, hdr->gso_size); unsigned int nh_off = p_off; struct skb_shared_info *shinfo = skb_shinfo(skb);
switch (gso_type & ~SKB_GSO_TCP_ECN) { case SKB_GSO_UDP: /* UFO may not include transport header in gso_size. */ nh_off -= thlen; break; case SKB_GSO_UDP_L4: if (!(hdr->flags & VIRTIO_NET_HDR_F_NEEDS_CSUM)) return -EINVAL; if (skb->csum_offset != offsetof(struct udphdr, check)) return -EINVAL; if (skb->len - p_off > gso_size * UDP_MAX_SEGMENTS) return -EINVAL; if (gso_type != SKB_GSO_UDP_L4) return -EINVAL; break; case SKB_GSO_TCPV4: case SKB_GSO_TCPV6: if (skb->ip_summed == CHECKSUM_PARTIAL && skb->csum_offset != offsetof(struct tcphdr, check)) return -EINVAL;
BUILD_BUG_ON(TCP_MIN_GSO_SIZE * GSO_MAX_SEGS < GSO_MAX_SIZE); gso_size = max(gso_size, TCP_MIN_GSO_SIZE); break; }
/* Kernel has a special handling for GSO_BY_FRAGS. */ if (gso_size == GSO_BY_FRAGS) return -EINVAL;
/* Too small packets are not really GSO ones. */ if (skb->len - nh_off > gso_size) { shinfo->gso_size = gso_size; shinfo->gso_type = gso_type;
/* Header must be checked, and gso_segs computed. */ shinfo->gso_type |= SKB_GSO_DODGY; shinfo->gso_segs = 0; } }
return 0;}
static inline int virtio_net_hdr_to_skb(struct sk_buff *skb, const struct virtio_net_hdr *hdr, bool little_endian){ return __virtio_net_hdr_to_skb(skb, hdr, little_endian, hdr->gso_type);}
/* This function must be called after virtio_net_hdr_from_skb(). */static inline void __virtio_net_set_hdrlen(const struct sk_buff *skb, struct virtio_net_hdr *hdr, bool little_endian){ u16 hdr_len;
hdr_len = skb_transport_offset(skb);
if (hdr->gso_type == VIRTIO_NET_HDR_GSO_UDP_L4) hdr_len += sizeof(struct udphdr); else hdr_len += tcp_hdrlen(skb);
hdr->hdr_len = __cpu_to_virtio16(little_endian, hdr_len);}
/* This function must be called after virtio_net_hdr_from_skb(). */static inline void __virtio_net_set_tnl_hdrlen(const struct sk_buff *skb, struct virtio_net_hdr *hdr){ u16 hdr_len;
hdr_len = skb_inner_transport_offset(skb);
if (hdr->gso_type == VIRTIO_NET_HDR_GSO_UDP_L4) hdr_len += sizeof(struct udphdr); else hdr_len += inner_tcp_hdrlen(skb);
hdr->hdr_len = __cpu_to_virtio16(true, hdr_len);}
static inline int virtio_net_hdr_from_skb(const struct sk_buff *skb, struct virtio_net_hdr *hdr, bool little_endian, bool has_data_valid, int vlan_hlen){ memset(hdr, 0, sizeof(*hdr)); /* no info leak */
if (skb_is_gso(skb)) { struct skb_shared_info *sinfo = skb_shinfo(skb);
/* This is a hint as to how much should be linear. */ hdr->hdr_len = __cpu_to_virtio16(little_endian, skb_headlen(skb)); hdr->gso_size = __cpu_to_virtio16(little_endian, sinfo->gso_size); if (sinfo->gso_type & SKB_GSO_TCPV4) hdr->gso_type = VIRTIO_NET_HDR_GSO_TCPV4; else if (sinfo->gso_type & SKB_GSO_TCPV6) hdr->gso_type = VIRTIO_NET_HDR_GSO_TCPV6; else if (sinfo->gso_type & SKB_GSO_UDP_L4) hdr->gso_type = VIRTIO_NET_HDR_GSO_UDP_L4; else return -EINVAL; if (sinfo->gso_type & SKB_GSO_TCP_ECN) hdr->gso_type |= VIRTIO_NET_HDR_GSO_ECN; } else hdr->gso_type = VIRTIO_NET_HDR_GSO_NONE;
if (skb->ip_summed == CHECKSUM_PARTIAL) { hdr->flags = VIRTIO_NET_HDR_F_NEEDS_CSUM; hdr->csum_start = __cpu_to_virtio16(little_endian, skb_checksum_start_offset(skb) + vlan_hlen); hdr->csum_offset = __cpu_to_virtio16(little_endian, skb->csum_offset); } else if (has_data_valid && skb->ip_summed == CHECKSUM_UNNECESSARY) { hdr->flags = VIRTIO_NET_HDR_F_DATA_VALID; } /* else everything is zero */
return 0;}
static inline unsigned int virtio_l3min(bool is_ipv6){ return is_ipv6 ? sizeof(struct ipv6hdr) : sizeof(struct iphdr);}
static inline intvirtio_net_hdr_tnl_to_skb(struct sk_buff *skb, const struct virtio_net_hdr_v1_hash_tunnel *vhdr, bool tnl_hdr_negotiated, bool tnl_csum_negotiated, bool little_endian){ const struct virtio_net_hdr *hdr = (const struct virtio_net_hdr *)vhdr; unsigned int inner_nh, outer_th, inner_th; unsigned int inner_l3min, outer_l3min; u8 gso_inner_type, gso_tunnel_type; bool outer_isv6, inner_isv6; int ret;
gso_tunnel_type = hdr->gso_type & VIRTIO_NET_HDR_GSO_UDP_TUNNEL; if (!gso_tunnel_type) return virtio_net_hdr_to_skb(skb, hdr, little_endian);
/* Tunnel not supported/negotiated, but the hdr asks for it. */ if (!tnl_hdr_negotiated) return -EINVAL;
/* Either ipv4 or ipv6. */ if (gso_tunnel_type == VIRTIO_NET_HDR_GSO_UDP_TUNNEL) return -EINVAL;
/* The UDP tunnel must carry a GSO packet, but no UFO. */ gso_inner_type = hdr->gso_type & ~(VIRTIO_NET_HDR_GSO_ECN | VIRTIO_NET_HDR_GSO_UDP_TUNNEL); if (!gso_inner_type || gso_inner_type == VIRTIO_NET_HDR_GSO_UDP) return -EINVAL;
/* Rely on csum being present. */ if (!(hdr->flags & VIRTIO_NET_HDR_F_NEEDS_CSUM)) return -EINVAL;
/* Validate offsets. */ outer_isv6 = gso_tunnel_type & VIRTIO_NET_HDR_GSO_UDP_TUNNEL_IPV6; inner_isv6 = gso_inner_type == VIRTIO_NET_HDR_GSO_TCPV6; inner_l3min = virtio_l3min(inner_isv6); outer_l3min = ETH_HLEN + virtio_l3min(outer_isv6);
inner_th = __virtio16_to_cpu(little_endian, hdr->csum_start); inner_nh = le16_to_cpu(vhdr->inner_nh_offset); outer_th = le16_to_cpu(vhdr->outer_th_offset); if (outer_th < outer_l3min || inner_nh < outer_th + sizeof(struct udphdr) || inner_th < inner_nh + inner_l3min) return -EINVAL;
/* Let the basic parsing deal with plain GSO features. */ ret = __virtio_net_hdr_to_skb(skb, hdr, true, hdr->gso_type & ~gso_tunnel_type); if (ret) return ret;
/* In case of USO, the inner protocol is still unknown and * `inner_isv6` is just a guess, additional parsing is needed. * The previous validation ensures that accessing an ipv4 inner * network header is safe. */ if (gso_inner_type == VIRTIO_NET_HDR_GSO_UDP_L4) { struct iphdr *iphdr = (struct iphdr *)(skb->data + inner_nh);
inner_isv6 = iphdr->version == 6; inner_l3min = virtio_l3min(inner_isv6); if (inner_th < inner_nh + inner_l3min) return -EINVAL; }
skb_set_inner_protocol(skb, inner_isv6 ? htons(ETH_P_IPV6) : htons(ETH_P_IP)); if (hdr->flags & VIRTIO_NET_HDR_F_UDP_TUNNEL_CSUM) { if (!tnl_csum_negotiated) return -EINVAL;
skb_shinfo(skb)->gso_type |= SKB_GSO_UDP_TUNNEL_CSUM; } else { skb_shinfo(skb)->gso_type |= SKB_GSO_UDP_TUNNEL; }
skb->inner_transport_header = inner_th + skb_headroom(skb); skb->inner_network_header = inner_nh + skb_headroom(skb); skb->inner_mac_header = inner_nh + skb_headroom(skb); skb->transport_header = outer_th + skb_headroom(skb); skb->encapsulation = 1; return 0;}
/* Checksum-related fields validation for the driver */static inline int virtio_net_handle_csum_offload(struct sk_buff *skb, struct virtio_net_hdr *hdr, bool tnl_csum_negotiated){ if (!(hdr->gso_type & VIRTIO_NET_HDR_GSO_UDP_TUNNEL)) { if (!(hdr->flags & VIRTIO_NET_HDR_F_DATA_VALID)) return 0;
skb->ip_summed = CHECKSUM_UNNECESSARY; if (!(hdr->flags & VIRTIO_NET_HDR_F_UDP_TUNNEL_CSUM)) return 0;
/* tunnel csum packets are invalid when the related * feature has not been negotiated */ if (!tnl_csum_negotiated) return -EINVAL; skb->csum_level = 1; return 0; }
/* DATA_VALID is mutually exclusive with NEEDS_CSUM, and GSO * over UDP tunnel requires the latter */ if (hdr->flags & VIRTIO_NET_HDR_F_DATA_VALID) return -EINVAL; return 0;}
/* * vlan_hlen always refers to the outermost MAC header. That also * means it refers to the only MAC header, if the packet does not carry * any encapsulation. */static inline intvirtio_net_hdr_tnl_from_skb(const struct sk_buff *skb, struct virtio_net_hdr_v1_hash_tunnel *vhdr, bool tnl_hdr_negotiated, bool little_endian, int vlan_hlen, bool has_data_valid, bool feature_hdrlen){ struct virtio_net_hdr *hdr = (struct virtio_net_hdr *)vhdr; unsigned int inner_nh, outer_th; int tnl_gso_type; int ret;
tnl_gso_type = skb_shinfo(skb)->gso_type & (SKB_GSO_UDP_TUNNEL | SKB_GSO_UDP_TUNNEL_CSUM); if (!tnl_gso_type) { ret = virtio_net_hdr_from_skb(skb, hdr, little_endian, has_data_valid, vlan_hlen); if (ret) return ret;
if (feature_hdrlen && hdr->hdr_len) __virtio_net_set_hdrlen(skb, hdr, little_endian);
return ret; }
/* Tunnel support not negotiated but skb ask for it. */ if (!tnl_hdr_negotiated) return -EINVAL;
vhdr->hash_hdr.hash_value_lo = 0; vhdr->hash_hdr.hash_value_hi = 0; vhdr->hash_hdr.hash_report = 0; vhdr->hash_hdr.padding = 0;
/* Let the basic parsing deal with plain GSO features. */ skb_shinfo(skb)->gso_type &= ~tnl_gso_type; ret = virtio_net_hdr_from_skb(skb, hdr, true, false, vlan_hlen); skb_shinfo(skb)->gso_type |= tnl_gso_type; if (ret) return ret;
if (feature_hdrlen && hdr->hdr_len) __virtio_net_set_tnl_hdrlen(skb, hdr);
if (skb->protocol == htons(ETH_P_IPV6)) hdr->gso_type |= VIRTIO_NET_HDR_GSO_UDP_TUNNEL_IPV6; else hdr->gso_type |= VIRTIO_NET_HDR_GSO_UDP_TUNNEL_IPV4;
if (skb_shinfo(skb)->gso_type & SKB_GSO_UDP_TUNNEL_CSUM) hdr->flags |= VIRTIO_NET_HDR_F_UDP_TUNNEL_CSUM;
inner_nh = skb->inner_network_header - skb_headroom(skb); outer_th = skb->transport_header - skb_headroom(skb); vhdr->inner_nh_offset = cpu_to_le16(inner_nh); vhdr->outer_th_offset = cpu_to_le16(outer_th); return 0;}
#endif /* _LINUX_VIRTIO_NET_H */