On Wed, Jun 05, 2024 at 05:21:25PM +0200, Laurent Vivier wrote: > This commit refactors the udp_update_hdr4() and udp_update_hdr6() functions > to improve code portability by replacing the udp_meta_t parameter with > more specific parameters for the IPv4 and IPv6 headers (iphdr/ipv6hdr) > and the source socket address (sockaddr_in/sockaddr_in6). > It also moves the tap_hdr_update() function call inside the udp_tap_send() > function not to have to pass the TAP header to udp_update_hdr4() and > udp_update_hdr6() > > This refactor reduces complexity by making the functions more modular and > ensuring that each function operates on more narrowly scoped data structures. > This will facilitate future backend introduction like vhost-user. > > Signed-off-by: Laurent Vivier Reviewed-by: David Gibson With the exception of the trivial nits that Stefano noted. Again, it would be great to get this merged quickly, so I can get my rebasing of the flow table stuff out of the way. > --- > udp.c | 60 +++++++++++++++++++++++++++++++++-------------------------- > 1 file changed, 34 insertions(+), 26 deletions(-) > > diff --git a/udp.c b/udp.c > index 3abafc994537..4295d48046a6 100644 > --- a/udp.c > +++ b/udp.c > @@ -556,7 +556,8 @@ static void udp_splice_sendfrom(const struct ctx *c, unsigned start, unsigned n, > /** > * udp_update_hdr4() - Update headers for one IPv4 datagram > * @c: Execution context > - * @bm: Pointer to udp_meta_t to update > + * @ip4h: Pre-filled IPv4 header (except for tot_len and saddr) > + * @s_in: Source socket address, filled in by recvmmsg() > * @bp: Pointer to udp_payload_t to update > * @dstport: Destination port number > * @dlen: Length of UDP payload > @@ -565,15 +566,16 @@ static void udp_splice_sendfrom(const struct ctx *c, unsigned start, unsigned n, > * Return: size of IPv4 payload (UDP header + data) > */ > static size_t udp_update_hdr4(const struct ctx *c, > - struct udp_meta_t *bm, struct udp_payload_t *bp, > + struct iphdr *ip4h, const struct sockaddr_in *s_in, > + struct udp_payload_t *bp, > in_port_t dstport, size_t dlen, > const struct timespec *now) > { > - in_port_t srcport = ntohs(bm->s_in.sa4.sin_port); > + in_port_t srcport = ntohs(s_in->sin_port); > const struct in_addr dst = c->ip4.addr_seen; > - struct in_addr src = bm->s_in.sa4.sin_addr; > + struct in_addr src = s_in->sin_addr; > size_t l4len = dlen + sizeof(bp->uh); > - size_t l3len = l4len + sizeof(bm->ip4h); > + size_t l3len = l4len + sizeof(*ip4h); > > if (!IN4_IS_ADDR_UNSPECIFIED(&c->ip4.dns_match) && > IN4_ARE_ADDR_EQUAL(&src, &c->ip4.dns_host) && srcport == 53 && > @@ -594,24 +596,24 @@ static size_t udp_update_hdr4(const struct ctx *c, > src = c->ip4.gw; > } > > - bm->ip4h.tot_len = htons(l3len); > - bm->ip4h.daddr = dst.s_addr; > - bm->ip4h.saddr = src.s_addr; > - bm->ip4h.check = csum_ip4_header(l3len, IPPROTO_UDP, src, dst); > + ip4h->tot_len = htons(l3len); > + ip4h->daddr = dst.s_addr; > + ip4h->saddr = src.s_addr; > + ip4h->check = csum_ip4_header(l3len, IPPROTO_UDP, src, dst); > > - bp->uh.source = bm->s_in.sa4.sin_port; > + bp->uh.source = s_in->sin_port; > bp->uh.dest = htons(dstport); > bp->uh.len = htons(l4len); > csum_udp4(&bp->uh, src, dst, bp->data, dlen); > > - tap_hdr_update(&bm->taph, l3len + sizeof(udp4_eth_hdr)); > return l4len; > } > > /** > * udp_update_hdr6() - Update headers for one IPv6 datagram > * @c: Execution context > - * @bm: Pointer to udp_meta_t to update > + * @ip6h: Pre-filled IPv6 header (except for payload_len and addresses) > + * @s_in: Source socket address, filled in by recvmmsg() > * @bp: Pointer to udp_payload_t to update > * @dstport: Destination port number > * @dlen: Length of UDP payload > @@ -620,13 +622,14 @@ static size_t udp_update_hdr4(const struct ctx *c, > * Return: size of IPv6 payload (UDP header + data) > */ > static size_t udp_update_hdr6(const struct ctx *c, > - struct udp_meta_t *bm, struct udp_payload_t *bp, > + struct ipv6hdr *ip6h, struct sockaddr_in6 *s_in6, > + struct udp_payload_t *bp, > in_port_t dstport, size_t dlen, > const struct timespec *now) > { > - const struct in6_addr *src = &bm->s_in.sa6.sin6_addr; > + const struct in6_addr *src = &s_in6->sin6_addr; > const struct in6_addr *dst = &c->ip6.addr_seen; > - in_port_t srcport = ntohs(bm->s_in.sa6.sin6_port); > + in_port_t srcport = ntohs(s_in6->sin6_port); > uint16_t l4len = dlen + sizeof(bp->uh); > > if (IN6_IS_ADDR_LINKLOCAL(src)) { > @@ -663,19 +666,18 @@ static size_t udp_update_hdr6(const struct ctx *c, > > } > > - bm->ip6h.payload_len = htons(l4len); > - bm->ip6h.daddr = *dst; > - bm->ip6h.saddr = *src; > - bm->ip6h.version = 6; > - bm->ip6h.nexthdr = IPPROTO_UDP; > - bm->ip6h.hop_limit = 255; > + ip6h->payload_len = htons(l4len); > + ip6h->daddr = *dst; > + ip6h->saddr = *src; > + ip6h->version = 6; > + ip6h->nexthdr = IPPROTO_UDP; > + ip6h->hop_limit = 255; > > - bp->uh.source = bm->s_in.sa6.sin6_port; > + bp->uh.source = s_in6->sin6_port; > bp->uh.dest = htons(dstport); > - bp->uh.len = bm->ip6h.payload_len; > + bp->uh.len = ip6h->payload_len; > csum_udp6(&bp->uh, src, dst, bp->data, dlen); > > - tap_hdr_update(&bm->taph, l4len + sizeof(bm->ip6h) + sizeof(udp6_eth_hdr)); > return l4len; > } > > @@ -708,11 +710,17 @@ static void udp_tap_send(const struct ctx *c, > size_t l4len; > > if (v6) { > - l4len = udp_update_hdr6(c, bm, bp, dstport, > + l4len = udp_update_hdr6(c, &bm->ip6h, > + &bm->s_in.sa6, bp, dstport, > udp6_l2_mh_sock[i].msg_len, now); > + tap_hdr_update(&bm->taph, l4len + sizeof(bm->ip6h) + > + sizeof(udp6_eth_hdr)); > } else { > - l4len = udp_update_hdr4(c, bm, bp, dstport, > + l4len = udp_update_hdr4(c, &bm->ip4h, > + &bm->s_in.sa4, bp, dstport, > udp4_l2_mh_sock[i].msg_len, now); > + tap_hdr_update(&bm->taph, l4len + sizeof(bm->ip4h) + > + sizeof(udp4_eth_hdr)); > } > tap_iov[i][UDP_IOV_PAYLOAD].iov_len = l4len; > } -- David Gibson | I'll have my music baroque, and my code david AT gibson.dropbear.id.au | minimalist, thank you. NOT _the_ _other_ | _way_ _around_! http://www.ozlabs.org/~dgibson