From mboxrd@z Thu Jan 1 00:00:00 1970 Authentication-Results: passt.top; dmarc=none (p=none dis=none) header.from=gibson.dropbear.id.au Authentication-Results: passt.top; dkim=pass (2048-bit key; secure) header.d=gibson.dropbear.id.au header.i=@gibson.dropbear.id.au header.a=rsa-sha256 header.s=202410 header.b=LqGdoWF3; dkim-atps=neutral Received: from mail.ozlabs.org (mail.ozlabs.org [IPv6:2404:9400:2221:ea00::3]) by passt.top (Postfix) with ESMTPS id 280595A0624 for ; Wed, 27 Nov 2024 04:54:25 +0100 (CET) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gibson.dropbear.id.au; s=202410; t=1732679649; bh=5bZ2Gj9oa711as5osOuQe+7V7A9xNATORMT8HdL+6mk=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=LqGdoWF3SVJ0LWfPv4LMZFYQ6mxbNByrMC4Mhu9jO5+PPNn5CJy9BnIZYxD/2HK2l YMwmGem+iICaj+6S510lWeDbXyAf2bOimUpzu4Sg0gB3tinCHl36lyMfxr8MCLWDBN 1ebk40YoJJj9pvFRekM0V4t8KMTdU0xD2eVNVQtDj8b2bjL2/uNGBt2nSsNlQH7CWG zDAWnIh2DvMMKD+YbbKUXCqRhz14+wYABeZqCI07lTvSM1p59492QSYkV6JOk+Sbqv OQG7upFFhcOayEMpKIcUTN7SgAErL+gFWfuWh8zzcjY5W4ceEaga/eo8zdWeQRcMsE LLz8ENtNJLGog== Received: by gandalf.ozlabs.org (Postfix, from userid 1007) id 4XyltT5b4jz4xgj; Wed, 27 Nov 2024 14:54:09 +1100 (AEDT) From: David Gibson To: Stefano Brivio , passt-dev@passt.top Subject: [PATCH 5/7] tcp: Merge tcp_update_check_tcp[46]() Date: Wed, 27 Nov 2024 14:54:08 +1100 Message-ID: <20241127035410.1167773-6-david@gibson.dropbear.id.au> X-Mailer: git-send-email 2.47.0 In-Reply-To: <20241127035410.1167773-1-david@gibson.dropbear.id.au> References: <20241127035410.1167773-1-david@gibson.dropbear.id.au> MIME-Version: 1.0 Content-Transfer-Encoding: 8bit Message-ID-Hash: 7CPC2BSJXSV6GANAYL2BGYFGAG36TZ5T X-Message-ID-Hash: 7CPC2BSJXSV6GANAYL2BGYFGAG36TZ5T 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: David Gibson X-Mailman-Version: 3.3.8 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: The only reason we need separate functions for the IPv4 and IPv6 case is to calculate the checksum of the IP pseudo-header, which is different for the two cases. However, the caller already knows which path it's on and can access the values needed for the pseudo-header partial sum more easily than tcp_update_check_tcp[46]() can. So, merge these functions into a single tcp_update_csum() function that just takes the pseudo-header partial sum, calculated in the caller. Signed-off-by: David Gibson --- tcp.c | 59 +++++++++++++++++--------------------------------- tcp_internal.h | 6 ++--- tcp_vu.c | 22 ++++++++++++------- 3 files changed, 36 insertions(+), 51 deletions(-) diff --git a/tcp.c b/tcp.c index 2f900fc..482e460 100644 --- a/tcp.c +++ b/tcp.c @@ -753,44 +753,16 @@ static void tcp_sock_set_bufsize(const struct ctx *c, int s) } /** - * tcp_update_check_tcp4() - Calculate TCP checksum for IPv4 - * @iph: IPv4 header + * tcp_update_csum() - Calculate TCP checksum + * @psum: Unfolded partial checksum of the IPv4 or IPv6 pseudo-header * @th: TCP header (updated) * @payload: TCP payload */ -void tcp_update_check_tcp4(const struct iphdr *iph, struct tcphdr *th, - struct iov_tail *payload) +void tcp_update_csum(uint32_t psum, struct tcphdr *th, struct iov_tail *payload) { - uint16_t l4len = ntohs(iph->tot_len) - sizeof(struct iphdr); - struct in_addr saddr = { .s_addr = iph->saddr }; - struct in_addr daddr = { .s_addr = iph->daddr }; - uint32_t sum; - - sum = proto_ipv4_header_psum(l4len, IPPROTO_TCP, saddr, daddr); - - th->check = 0; - sum = csum_unfolded(th, sizeof(*th), sum); - th->check = csum_iov_tail(payload, sum); -} - -/** - * tcp_update_check_tcp6() - Calculate TCP checksum for IPv6 - * @ip6h: IPv6 header - * @th: TCP header (updated) - * @payload: TCP payload - */ -void tcp_update_check_tcp6(const struct ipv6hdr *ip6h, struct tcphdr *th, - struct iov_tail *payload) -{ - uint16_t l4len = ntohs(ip6h->payload_len); - uint32_t sum; - - sum = proto_ipv6_header_psum(l4len, IPPROTO_TCP, &ip6h->saddr, - &ip6h->daddr); - th->check = 0; - sum = csum_unfolded(th, sizeof(*th), sum); - th->check = csum_iov_tail(payload, sum); + psum = csum_unfolded(th, sizeof(*th), psum); + th->check = csum_iov_tail(payload, psum); } /** @@ -937,10 +909,14 @@ void tcp_fill_headers4(const struct tcp_tap_conn *conn, tcp_fill_header(th, conn, seq); - if (no_tcp_csum) + if (no_tcp_csum) { th->check = 0; - else - tcp_update_check_tcp4(iph, th, payload); + } else { + uint32_t psum = proto_ipv4_header_psum(l4len, IPPROTO_TCP, + *src4, *dst4); + + tcp_update_csum(psum, th, payload); + } tap_hdr_update(taph, l3len + sizeof(struct ethhdr)); } @@ -978,10 +954,15 @@ void tcp_fill_headers6(const struct tcp_tap_conn *conn, tcp_fill_header(th, conn, seq); - if (no_tcp_csum) + if (no_tcp_csum) { th->check = 0; - else - tcp_update_check_tcp6(ip6h, th, payload); + } else { + uint32_t psum = proto_ipv6_header_psum(l4len, IPPROTO_TCP, + &ip6h->saddr, + &ip6h->daddr); + + tcp_update_csum(psum, th, payload); + } tap_hdr_update(taph, l4len + sizeof(*ip6h) + sizeof(struct ethhdr)); } diff --git a/tcp_internal.h b/tcp_internal.h index 9732b5b..cff06e0 100644 --- a/tcp_internal.h +++ b/tcp_internal.h @@ -162,10 +162,8 @@ void tcp_rst_do(const struct ctx *c, struct tcp_tap_conn *conn); struct tcp_info_linux; -void tcp_update_check_tcp4(const struct iphdr *iph, struct tcphdr *th, - struct iov_tail *payload); -void tcp_update_check_tcp6(const struct ipv6hdr *ip6h, struct tcphdr *th, - struct iov_tail *payload); +void tcp_update_csum(uint32_t psum, struct tcphdr *th, + struct iov_tail *payload); void tcp_fill_headers4(const struct tcp_tap_conn *conn, struct tap_hdr *taph, struct iphdr *iph, struct tcphdr *th, struct iov_tail *payload, diff --git a/tcp_vu.c b/tcp_vu.c index a4ec512..081c752 100644 --- a/tcp_vu.c +++ b/tcp_vu.c @@ -70,22 +70,28 @@ static void tcp_vu_update_check(const struct flowside *tapside, struct iovec *iov, int iov_cnt) { char *base = iov[0].iov_base; + struct iov_tail payload; + struct tcphdr *th; + uint32_t psum; if (inany_v4(&tapside->oaddr)) { - struct tcphdr *th = vu_payloadv4(base); + const struct in_addr *src4 = inany_v4(&tapside->oaddr); + const struct in_addr *dst4 = inany_v4(&tapside->eaddr); const struct iphdr *iph = vu_ip(base); - struct iov_tail payload = IOV_TAIL(iov, iov_cnt, - (char *)(th + 1) - base); + size_t l4len = ntohs(iph->tot_len) - sizeof(*iph); - tcp_update_check_tcp4(iph, th, &payload); + th = vu_payloadv4(base); + psum = proto_ipv4_header_psum(l4len, IPPROTO_TCP, *src4, *dst4); } else { - struct tcphdr *th = vu_payloadv6(base); const struct ipv6hdr *ip6h = vu_ip(base); - struct iov_tail payload = IOV_TAIL(iov, iov_cnt, - (char *)(th + 1) - base); + size_t l4len = ntohs(ip6h->payload_len); - tcp_update_check_tcp6(ip6h, th, &payload); + th = vu_payloadv6(base); + psum = proto_ipv6_header_psum(l4len, IPPROTO_TCP, + &ip6h->saddr, &ip6h->daddr); } + payload = IOV_TAIL(iov, iov_cnt, (char *)(th + 1) - base); + tcp_update_csum(psum, th, &payload); } /** -- 2.47.0