From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from gandalf.ozlabs.org (mail.ozlabs.org [IPv6:2404:9400:2221:ea00::3]) by passt.top (Postfix) with ESMTPS id 2C96D5A0270 for ; Tue, 18 Oct 2022 14:08:15 +0200 (CEST) Received: by gandalf.ozlabs.org (Postfix, from userid 1007) id 4MsCLH53Pkz4xGv; Tue, 18 Oct 2022 23:08:07 +1100 (AEDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gibson.dropbear.id.au; s=201602; t=1666094887; bh=F3VoUse0+lE008HRzQDdvdrPbhDNZzLF4IvTXibeslI=; h=Date:From:To:Cc:Subject:References:In-Reply-To:From; b=CgxE3FUW60GDPXFfGu3BGE4fqSHKIibn31hC+8wK9OA83XDuMsOtDw8yr5hTr1w/K yST113EiTE1vOr6KwSv8LJLZ0qH+wOCrRlrT3kXHFELu0OYUCTeNnG2m94sSsUURwC QWpoiqmmNJJwf8BqU9j9qfejuj00PWNYAve24ACw= Date: Tue, 18 Oct 2022 23:07:43 +1100 From: David Gibson To: Stefano Brivio Subject: Re: [PATCH 09/14] Split tap_ip_send() into IPv4 and IPv6 specific functions Message-ID: References: <20221017085807.473470-1-david@gibson.dropbear.id.au> <20221017085807.473470-10-david@gibson.dropbear.id.au> <20221018050611.02d79478@elisabeth> MIME-Version: 1.0 Content-Type: multipart/signed; micalg=pgp-sha256; protocol="application/pgp-signature"; boundary="frKgLE6mtWncRg6v" Content-Disposition: inline In-Reply-To: <20221018050611.02d79478@elisabeth> Message-ID-Hash: EK3KTUFIZBT53IW2NPOT63WDGKU75A3C X-Message-ID-Hash: EK3KTUFIZBT53IW2NPOT63WDGKU75A3C X-MailFrom: dgibson@gandalf.ozlabs.org X-Mailman-Rule-Misses: dmarc-mitigation; no-senders; approved; emergency; loop; banned-address; member-moderation; nonmember-moderation; administrivia; implicit-dest; max-recipients; max-size; news-moderation; no-subject; digests; suspicious-header CC: passt-dev@passt.top X-Mailman-Version: 3.3.3 Precedence: list List-Id: Development discussion and patches for passt Archived-At: <> Archived-At: List-Archive: <> List-Archive: List-Help: List-Owner: List-Post: List-Subscribe: List-Unsubscribe: --frKgLE6mtWncRg6v Content-Type: text/plain; charset=us-ascii Content-Disposition: inline Content-Transfer-Encoding: quoted-printable On Tue, Oct 18, 2022 at 05:06:11AM +0200, Stefano Brivio wrote: > On Mon, 17 Oct 2022 19:58:02 +1100 > David Gibson wrote: >=20 > > The IPv4 and IPv6 paths in tap_ip_send() have very little in common, and > > it turns out that every caller (statically) knows if it is using IPv4 or > > IPv6. So split into separate tap_ip4_send() and tap_ip6_send() functio= ns. > > Use a new tap_l2_hdr() function for the very small common part. > >=20 > > While we're there, make some minor cleanups: > > - We were double writing some fields in the IPv6 header, so that it > > temporary matched the pseudo-header for checksum calculation. With > > recent checksum reworks, this isn't neccessary any more. > > - We don't use any IPv4 header options, so use some sizeof() construc= ts > > instead of some open coded values for header length. > > - The comment used to say that the flow label was for TCP over IPv6, = but > > in fact the only thing we used it for was ICMPv6 >=20 > ...right, this used to be the data path. Makes sense. Realized that comment isn't quite correct, because it was DHCPv6 rather than ICMPv6 traffic that got the flow labels. > > Signed-off-by: David Gibson > > --- > > dhcpv6.c | 6 +- > > icmp.c | 10 +--- > > tap.c | 176 +++++++++++++++++++++++++++++-------------------------- > > tap.h | 6 +- > > 4 files changed, 102 insertions(+), 96 deletions(-) > >=20 > > diff --git a/dhcpv6.c b/dhcpv6.c > > index e7640ce..7829968 100644 > > --- a/dhcpv6.c > > +++ b/dhcpv6.c > > @@ -531,8 +531,8 @@ int dhcpv6(struct ctx *c, const struct pool *p, > > =20 > > resp_not_on_link.hdr.xid =3D mh->xid; > > =20 > > - tap_ip_send(c, src, IPPROTO_UDP, > > - (char *)&resp_not_on_link, n, mh->xid); > > + tap_ip6_send(c, src, IPPROTO_UDP, > > + (char *)&resp_not_on_link, n, mh->xid); > > =20 > > return 1; > > } > > @@ -580,7 +580,7 @@ int dhcpv6(struct ctx *c, const struct pool *p, > > =20 > > resp.hdr.xid =3D mh->xid; > > =20 > > - tap_ip_send(c, src, IPPROTO_UDP, (char *)&resp, n, mh->xid); > > + tap_ip6_send(c, src, IPPROTO_UDP, (char *)&resp, n, mh->xid); > > c->ip6.addr_seen =3D c->ip6.addr; > > =20 > > return 1; > > diff --git a/icmp.c b/icmp.c > > index 21ea2d7..61c2d90 100644 > > --- a/icmp.c > > +++ b/icmp.c > > @@ -69,10 +69,6 @@ static uint8_t icmp_act[IP_VERSIONS][DIV_ROUND_UP(IC= MP_NUM_IDS, 8)]; > > void icmp_sock_handler(const struct ctx *c, union epoll_ref ref, > > uint32_t events, const struct timespec *now) > > { > > - struct in6_addr a6 =3D { .s6_addr =3D { 0, 0, 0, 0, > > - 0, 0, 0, 0, > > - 0, 0, 0xff, 0xff, > > - 0, 0, 0, 0 } }; > > union icmp_epoll_ref *iref =3D &ref.r.p.icmp; > > struct sockaddr_storage sr; > > socklen_t sl =3D sizeof(sr); > > @@ -109,7 +105,7 @@ void icmp_sock_handler(const struct ctx *c, union e= poll_ref ref, > > icmp_id_map[V6][id].seq =3D seq; > > } > > =20 > > - tap_ip_send(c, &sr6->sin6_addr, IPPROTO_ICMPV6, buf, n, 0); > > + tap_ip6_send(c, &sr6->sin6_addr, IPPROTO_ICMPV6, buf, n, 0); > > } else { > > struct sockaddr_in *sr4 =3D (struct sockaddr_in *)&sr; > > struct icmphdr *ih =3D (struct icmphdr *)buf; > > @@ -127,9 +123,7 @@ void icmp_sock_handler(const struct ctx *c, union e= poll_ref ref, > > icmp_id_map[V4][id].seq =3D seq; > > } > > =20 > > - memcpy(&a6.s6_addr[12], &sr4->sin_addr, sizeof(sr4->sin_addr)); > > - > > - tap_ip_send(c, &a6, IPPROTO_ICMP, buf, n, 0); > > + tap_ip4_send(c, sr4->sin_addr.s_addr, IPPROTO_ICMP, buf, n); > > } > > } > > =20 > > diff --git a/tap.c b/tap.c > > index ae75fac..45547ac 100644 > > --- a/tap.c > > +++ b/tap.c > > @@ -109,100 +109,110 @@ const struct in6_addr *tap_ip6_daddr(const stru= ct ctx *c, > > } > > =20 > > /** > > - * tap_ip_send() - Send IP packet, with L2 headers, calculating L3/L4 = checksums > > + * tap_l2_hdr() - Build an L2 header for an inbound packet > > * @c: Execution context > > - * @src: IPv6 source address, IPv4-mapped for IPv4 sources > > - * @proto: L4 protocol number > > - * @in: Payload > > - * @len: L4 payload length > > - * @flow: Flow label for TCP over IPv6 > > + * @buf: Buffer address at which to generate header > > + * @proto: Ethernet protocol number for L3 > > + * > > + * Returns a pointer at which to write the packet's payload >=20 > * Return: ... Done. --=20 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 --frKgLE6mtWncRg6v Content-Type: application/pgp-signature; name="signature.asc" -----BEGIN PGP SIGNATURE----- iQIzBAEBCAAdFiEEoULxWu4/Ws0dB+XtgypY4gEwYSIFAmNOlwgACgkQgypY4gEw YSLEkRAAmPYqNZBwwziCIwb6+0BgJ9AAwblO5cQ73ec5kV5HclowHb2y2eTGwufT lWYSNLUGe0zm7iYDQ+kLJ3xdzKRlf5jGG+GVxuvlmQYGdQErRXnjTG+9xPBirNqO ZzaQ+6WX1HryT5+su+4/35w31Erf9hXKX6yMQ7OMh73J5188qxTmfwXJAxyjfgO0 LbH54fmYkC+IYNAHKxNNECM6MXe3uhQaotZV5JrB2M11yXlOgMWu9j9EAQTPXB9P 6AYXNdhnfJNM2jsdVrcy1m56S3DwQ9AOSVjsWwztj6/hP4JXKI9S7Qs+/5yIRXxZ YRDPXjKDP9IeF83T0c+strUTshJrg3ICaC/hXSszTkONiADi3b/3xc2GGSgY7EEU eEf5MiUQwpvd0mZiJqz7GclTwLjpMpjuvj18olem2yaIBb7Fm30u09g6jXM6dByu aJxmeZSjq/+sqKVNLa2hSvCdPjdzOidmxUfF8/MfCALci3dquu66xwq6OJ0zxdn2 PxVkstJ6XjPOudxEDNj05uuy2e/jrlfQGRm+64AlFqxMxdYA7p34auPA00Tps6Cc ZUSLxygxUBv/xgihnO08yWgec3vPw9fesd2mpEaI4l9HGoQlnhhLyLjqMtXstbrh 22rJxCZP7DHu7Kl9O13LRxrtP80X3fr+t8lmDt3mmFgtpQa9Q4o= =MVZs -----END PGP SIGNATURE----- --frKgLE6mtWncRg6v--