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=aEQnsRZy; dkim-atps=neutral Received: from mail.ozlabs.org (mail.ozlabs.org [IPv6:2404:9400:2221:ea00::3]) by passt.top (Postfix) with ESMTPS id 343FD5A061D for ; Mon, 04 Nov 2024 09:40:29 +0100 (CET) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gibson.dropbear.id.au; s=202410; t=1730709607; bh=pUx/JhHom8otjkrj4Y8BecKeZYs3EF5B6p4m/lVbCR8=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=aEQnsRZy4Q7Ko0HuqwOgpsQXyfK0mIvlb24203SaIDHxaYof6+Mo8NNvayxYsdIQo A5sq954SdgALpe7svTjc1kWoguYW8KRpTiUnuj+JlFGdNTQC3mVnk2kINN2e9es4L8 j15cooAsX9818l/Dp3XFZVvhObVmVjpiIlG75ZEalK+iD6VPMMOD16rAsaoqYgLXTM v9syA68au0hpQslf72ViKqtw55vJe6PVr2hcKwtKF5r14Lgbauh7rd5s2c9UJNIwzZ 38fQvyygkfyiuBhQcubNi83odE5in9tV/6A7cOou3+4FxDIEijGykRZC2OejjLzhq+ W3jBV7sSbFrrg== Received: by gandalf.ozlabs.org (Postfix, from userid 1007) id 4XhlK352k8z4xKl; Mon, 4 Nov 2024 19:40:07 +1100 (AEDT) From: David Gibson To: passt-dev@passt.top, Stefano Brivio Subject: [PATCH v9 19/20] tcp: Merge tcp_update_check_tcp[46]() Date: Mon, 4 Nov 2024 19:40:02 +1100 Message-ID: <20241104084004.3544294-20-david@gibson.dropbear.id.au> X-Mailer: git-send-email 2.47.0 In-Reply-To: <20241104084004.3544294-1-david@gibson.dropbear.id.au> References: <20241104084004.3544294-1-david@gibson.dropbear.id.au> MIME-Version: 1.0 Content-Transfer-Encoding: 8bit Message-ID-Hash: MOYIJ33JNIS5JLRXYXWIK763RYT7EPZB X-Message-ID-Hash: MOYIJ33JNIS5JLRXYXWIK763RYT7EPZB 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 | 65 +++++++++++++++++--------------------------------- tcp_internal.h | 9 +++---- tcp_vu.c | 18 +++++++++----- 3 files changed, 37 insertions(+), 55 deletions(-) diff --git a/tcp.c b/tcp.c index 5e26243..297eb8c 100644 --- a/tcp.c +++ b/tcp.c @@ -753,50 +753,20 @@ 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) * @iov: IO vector containing the TCP payload * @iov_cnt: Length of @iov * @doffset: TCP payload offset in @iov */ -void tcp_update_check_tcp4(const struct iphdr *iph, struct tcphdr *th, - const struct iovec *iov, int iov_cnt, - size_t doffset) +void tcp_update_csum(uint32_t psum, struct tcphdr *th, + const struct iovec *iov, int iov_cnt, + size_t doffset) { - 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(iov, iov_cnt, doffset, sum); -} - -/** - * tcp_update_check_tcp6() - Calculate TCP checksum for IPv6 - * @ip6h: IPv6 header - * @th: TCP header (updated) - * @iov: IO vector containing the TCP payload - * @iov_cnt: Length of @iov - * @doffset: TCP payload offset in @iov - */ -void tcp_update_check_tcp6(const struct ipv6hdr *ip6h, struct tcphdr *th, - const struct iovec *iov, int iov_cnt, - size_t doffset) -{ - 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(iov, iov_cnt, doffset, sum); + psum = csum_unfolded(th, sizeof(*th), psum); + th->check = csum_iov(iov, iov_cnt, doffset, psum); } /** @@ -948,10 +918,14 @@ 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, iov, iov_cnt, doffset); + } else { + uint32_t psum = proto_ipv4_header_psum(l4len, IPPROTO_TCP, + *src4, *dst4); + + tcp_update_csum(psum, th, iov, iov_cnt, doffset); + } tap_hdr_update(taph, l3len + sizeof(struct ethhdr)); } @@ -993,10 +967,15 @@ 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, iov, iov_cnt, doffset); + } else { + uint32_t psum = proto_ipv6_header_psum(l4len, IPPROTO_TCP, + &ip6h->saddr, + &ip6h->daddr); + + tcp_update_csum(psum, th, iov, iov_cnt, doffset); + } tap_hdr_update(taph, l4len + sizeof(*ip6h) + sizeof(struct ethhdr)); } diff --git a/tcp_internal.h b/tcp_internal.h index 8f9267c..a2de15a 100644 --- a/tcp_internal.h +++ b/tcp_internal.h @@ -177,12 +177,9 @@ 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, - const struct iovec *iov, int iov_cnt, - size_t doffset); -void tcp_update_check_tcp6(const struct ipv6hdr *ip6h, struct tcphdr *th, - const struct iovec *iov, int iov_cnt, - size_t doffset); +void tcp_update_csum(uint32_t psum, struct tcphdr *th, + const struct iovec *iov, int iov_cnt, + size_t doffset); void tcp_fill_headers4(const struct tcp_tap_conn *conn, struct tap_hdr *taph, struct iphdr *iph, struct tcphdr *th, diff --git a/tcp_vu.c b/tcp_vu.c index bf45c74..916e35d 100644 --- a/tcp_vu.c +++ b/tcp_vu.c @@ -67,20 +67,26 @@ static void tcp_vu_update_check(const struct flowside *tapside, struct iovec *iov, int iov_used) { char *base = iov[0].iov_base; + 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); + size_t l4len = ntohs(iph->tot_len) - sizeof(*th); - tcp_update_check_tcp4(iph, th, iov, iov_used, - (char *)(th + 1) - base); + 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); + size_t l4len = ntohs(ip6h->payload_len); - tcp_update_check_tcp6(ip6h, th, iov, iov_used, - (char *)(th + 1) - base); + th = vu_payloadv6(base); + psum = proto_ipv6_header_psum(l4len, IPPROTO_TCP, + &ip6h->saddr, &ip6h->daddr); } + tcp_update_csum(psum, th, iov, iov_used, (char *)(th + 1) - base); } /** -- 2.47.0