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=AIXJH7F/; dkim-atps=neutral Received: from mail.ozlabs.org (mail.ozlabs.org [IPv6:2404:9400:2221:ea00::3]) by passt.top (Postfix) with ESMTPS id 0BEB65A061B for ; Mon, 28 Oct 2024 10:41:05 +0100 (CET) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gibson.dropbear.id.au; s=202410; t=1730108451; bh=tqxRGpGvQyY+whnYQdIW2VtBEsEr0w1+KBiiSmuLpQw=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=AIXJH7F/cA5R3FiEESDDt/i/jZifljkmvQAdCniLUgxuXCAj2cMcCtwO96NATw3Sb jr1B76iv+gvdGebsVkTiUlUpBsnEb0+9ETGpw0VO0O8oYPsS2HXGNMfv9PhTEmIYz4 SRYlkQ3Fo2GxwQB317ySsM1qGtNQP4X3W1MMbFiFJ4npT/TEO7vlRh8voolu2hEY2c 2jAL+Epc4BgV8u7RuBVboS+3UPaS9bXBuU6waN2SOQKnxeXuHCV6hlbHZZN9ytxOYg 9Yo4gXR6XgQhaNDRmOH3bXu5tZJbP/Q0UVzmXKtbV770+tYR0itGimiW7oZKmKKKW5 vot5LSG977XbQ== Received: by gandalf.ozlabs.org (Postfix, from userid 1007) id 4XcT0M20Jdz4x5J; Mon, 28 Oct 2024 20:40:51 +1100 (AEDT) From: David Gibson To: Stefano Brivio , Laurent Vivier , passt-dev@passt.top Subject: [PATCH 1/7] tcp: Pass TCP header and payload separately to tcp_update_check_tcp[46]() Date: Mon, 28 Oct 2024 20:40:44 +1100 Message-ID: <20241028094050.1609090-2-david@gibson.dropbear.id.au> X-Mailer: git-send-email 2.47.0 In-Reply-To: <20241028094050.1609090-1-david@gibson.dropbear.id.au> References: <20241028094050.1609090-1-david@gibson.dropbear.id.au> MIME-Version: 1.0 Content-Transfer-Encoding: 8bit Message-ID-Hash: DIKBNWZDUJ262R6JJ64IEQ5Q65V5RKQG X-Message-ID-Hash: DIKBNWZDUJ262R6JJ64IEQ5Q65V5RKQG 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: Currently these expects both the TCP header and payload in a single IOV, and goes to some trouble to locate the checksum field within it. In the current caller we've already know where the TCP header is, so we might as well just pass it in. This will need to work a bit differently for vhost-user, but that code already needs to locate the TCP header for other reasons, so again we can just pass it in. Signed-off-by: David Gibson --- tcp.c | 104 ++++++++++++++-------------------------------------------- 1 file changed, 24 insertions(+), 80 deletions(-) diff --git a/tcp.c b/tcp.c index 0569dc6..f2898ff 100644 --- a/tcp.c +++ b/tcp.c @@ -753,104 +753,48 @@ static void tcp_sock_set_bufsize(const struct ctx *c, int s) /** * tcp_update_check_tcp4() - Calculate TCP checksum for IPv4 * @iph: IPv4 header - * @iov: Pointer to the array of IO vectors - * @iov_cnt: Length of the array - * @l4offset: IPv4 payload offset in the iovec array + * @th: TCP header (updated) + * @iov: IO vector containing the TCP payload + * @iov_cnt: Length of @iov + * @doffset: TCP payload offset in @iov */ -static void tcp_update_check_tcp4(const struct iphdr *iph, +static void tcp_update_check_tcp4(const struct iphdr *iph, struct tcphdr *th, const struct iovec *iov, int iov_cnt, - size_t l4offset) + 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 }; - size_t check_ofs; - __sum16 *check; - int check_idx; uint32_t sum; - char *ptr; sum = proto_ipv4_header_psum(l4len, IPPROTO_TCP, saddr, daddr); - check_idx = iov_skip_bytes(iov, iov_cnt, - l4offset + offsetof(struct tcphdr, check), - &check_ofs); - - if (check_idx >= iov_cnt) { - err("TCP4 buffer is too small, iov size %zd, check offset %zd", - iov_size(iov, iov_cnt), - l4offset + offsetof(struct tcphdr, check)); - return; - } - - if (check_ofs + sizeof(*check) > iov[check_idx].iov_len) { - err("TCP4 checksum field memory is not contiguous " - "check_ofs %zd check_idx %d iov_len %zd", - check_ofs, check_idx, iov[check_idx].iov_len); - return; - } - - ptr = (char *)iov[check_idx].iov_base + check_ofs; - if ((uintptr_t)ptr & (__alignof__(*check) - 1)) { - err("TCP4 checksum field is not correctly aligned in memory"); - return; - } - - check = (__sum16 *)ptr; - - *check = 0; - *check = csum_iov(iov, iov_cnt, l4offset, sum); + 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 - * @iov: Pointer to the array of IO vectors - * @iov_cnt: Length of the array - * @l4offset: IPv6 payload offset in the iovec array + * @th: TCP header (updated) + * @iov: IO vector containing the TCP payload + * @iov_cnt: Length of @iov + * @doffset: TCP payload offset in @iov */ -static void tcp_update_check_tcp6(const struct ipv6hdr *ip6h, +static void tcp_update_check_tcp6(const struct ipv6hdr *ip6h, struct tcphdr *th, const struct iovec *iov, int iov_cnt, - size_t l4offset) + size_t doffset) { uint16_t l4len = ntohs(ip6h->payload_len); - size_t check_ofs; - __sum16 *check; - int check_idx; uint32_t sum; - char *ptr; sum = proto_ipv6_header_psum(l4len, IPPROTO_TCP, &ip6h->saddr, &ip6h->daddr); - check_idx = iov_skip_bytes(iov, iov_cnt, - l4offset + offsetof(struct tcphdr, check), - &check_ofs); - - if (check_idx >= iov_cnt) { - err("TCP6 buffer is too small, iov size %zd, check offset %zd", - iov_size(iov, iov_cnt), - l4offset + offsetof(struct tcphdr, check)); - return; - } - - if (check_ofs + sizeof(*check) > iov[check_idx].iov_len) { - err("TCP6 checksum field memory is not contiguous " - "check_ofs %zd check_idx %d iov_len %zd", - check_ofs, check_idx, iov[check_idx].iov_len); - return; - } - - ptr = (char *)iov[check_idx].iov_base + check_ofs; - if ((uintptr_t)ptr & (__alignof__(*check) - 1)) { - err("TCP6 checksum field is not correctly aligned in memory"); - return; - } - - check = (__sum16 *)ptr; - - *check = 0; - *check = csum_iov(iov, iov_cnt, l4offset, sum); + th->check = 0; + sum = csum_unfolded(th, sizeof(*th), sum); + th->check = csum_iov(iov, iov_cnt, doffset, sum); } /** @@ -1005,11 +949,11 @@ static size_t tcp_fill_headers4(const struct tcp_tap_conn *conn, bp->th.check = 0; } else { const struct iovec iov = { - .iov_base = bp, - .iov_len = ntohs(iph->tot_len) - sizeof(struct iphdr), + .iov_base = bp->data, + .iov_len = dlen, }; - tcp_update_check_tcp4(iph, &iov, 1, 0); + tcp_update_check_tcp4(iph, &bp->th, &iov, 1, 0); } tap_hdr_update(taph, l3len + sizeof(struct ethhdr)); @@ -1056,11 +1000,11 @@ static size_t tcp_fill_headers6(const struct tcp_tap_conn *conn, bp->th.check = 0; } else { const struct iovec iov = { - .iov_base = bp, - .iov_len = ntohs(ip6h->payload_len) + .iov_base = bp->data, + .iov_len = dlen, }; - tcp_update_check_tcp6(ip6h, &iov, 1, 0); + tcp_update_check_tcp6(ip6h, &bp->th, &iov, 1, 0); } tap_hdr_update(taph, l4len + sizeof(*ip6h) + sizeof(struct ethhdr)); -- 2.47.0