From mboxrd@z Thu Jan 1 00:00:00 1970 Authentication-Results: passt.top; dmarc=pass (p=none dis=none) header.from=redhat.com Authentication-Results: passt.top; dkim=pass (1024-bit key; unprotected) header.d=redhat.com header.i=@redhat.com header.a=rsa-sha256 header.s=mimecast20190719 header.b=GMcpqamX; dkim-atps=neutral Received: from us-smtp-delivery-124.mimecast.com (us-smtp-delivery-124.mimecast.com [170.10.129.124]) by passt.top (Postfix) with ESMTPS id 76D525A0626 for ; Thu, 20 Feb 2025 17:02:43 +0100 (CET) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1740067362; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:mime-version:mime-version:content-type:content-type: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references; bh=zL++ndLxkPzH8Vp9FD2/pvreaUUUH0gjqvbR6T3VlNM=; b=GMcpqamXoFZ6TLq96u6oXnnjGX19uGJN+/DR/0mqklm34rM4GyF7hbutPewRSsYbrpTdox ogDXWdtZTU8JlVpPLU6l4Bh5ffb9iEx0oCR1hr1ggpGRQxPHKpBViCNo/9GT/G/S/Thpv8 zmswPaw95Onk5HCaPkzpsHy8CxWDBMk= Received: from mx-prod-mc-06.mail-002.prod.us-west-2.aws.redhat.com (ec2-35-165-154-97.us-west-2.compute.amazonaws.com [35.165.154.97]) by relay.mimecast.com with ESMTP with STARTTLS (version=TLSv1.3, cipher=TLS_AES_256_GCM_SHA384) id us-mta-155-lxyyCv2pNqizcXkFk60VqA-1; Thu, 20 Feb 2025 11:02:41 -0500 X-MC-Unique: lxyyCv2pNqizcXkFk60VqA-1 X-Mimecast-MFC-AGG-ID: lxyyCv2pNqizcXkFk60VqA_1740067360 Received: from mx-prod-int-03.mail-002.prod.us-west-2.aws.redhat.com (mx-prod-int-03.mail-002.prod.us-west-2.aws.redhat.com [10.30.177.12]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature RSA-PSS (2048 bits) server-digest SHA256) (No client certificate requested) by mx-prod-mc-06.mail-002.prod.us-west-2.aws.redhat.com (Postfix) with ESMTPS id 2CA33180087A for ; Thu, 20 Feb 2025 16:02:40 +0000 (UTC) Received: from jmaloy-thinkpadp16vgen1.rmtcaqc.csb (unknown [10.22.65.244]) by mx-prod-int-03.mail-002.prod.us-west-2.aws.redhat.com (Postfix) with ESMTP id B903B1955BCB; Thu, 20 Feb 2025 16:02:38 +0000 (UTC) From: Jon Maloy To: passt-dev@passt.top, sbrivio@redhat.com, lvivier@redhat.com, dgibson@redhat.com, jmaloy@redhat.com Subject: [PATCH v4 1/2] tap: break out building of udp header from tap_udp4_send function Date: Thu, 20 Feb 2025 11:02:34 -0500 Message-ID: <20250220160235.2467261-2-jmaloy@redhat.com> In-Reply-To: <20250220160235.2467261-1-jmaloy@redhat.com> References: <20250220160235.2467261-1-jmaloy@redhat.com> MIME-Version: 1.0 X-Scanned-By: MIMEDefang 3.0 on 10.30.177.12 X-Mimecast-Spam-Score: 0 X-Mimecast-MFC-PROC-ID: QTvNd_nB_hS5P1ekWi25wCsw488LO3xTwSyYKPvyEfg_1740067360 X-Mimecast-Originator: redhat.com Content-Transfer-Encoding: 8bit content-type: text/plain; charset="US-ASCII"; x-default=true Message-ID-Hash: ZRNY47S3YWN5N7D32WNN5T66L3GPLOCM X-Message-ID-Hash: ZRNY47S3YWN5N7D32WNN5T66L3GPLOCM X-MailFrom: jmaloy@redhat.com 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 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: We will need to build the UDP header at other locations than in function tap_udp4_send(), so we break that part out to a separate function. Signed-off-by: Jon Maloy --- tap.c | 32 +++++++++++++++++++++++++------- tap.h | 6 +++++- 2 files changed, 30 insertions(+), 8 deletions(-) diff --git a/tap.c b/tap.c index dfe6dcf..95d64bf 100644 --- a/tap.c +++ b/tap.c @@ -162,7 +162,7 @@ static void *tap_push_ip4h(struct iphdr *ip4h, struct in_addr src, } /** - * tap_udp4_send() - Send UDP over IPv4 packet + * tap_push_uh4() - Build UDPv4 header with checksum * @c: Execution context * @src: IPv4 source address * @sport: UDP source port @@ -171,15 +171,11 @@ static void *tap_push_ip4h(struct iphdr *ip4h, struct in_addr src, * @in: UDP payload contents (not including UDP header) * @dlen: UDP payload length (not including UDP header) */ -void tap_udp4_send(const struct ctx *c, struct in_addr src, in_port_t sport, +void *tap_push_uh4(struct udphdr *uh, struct in_addr src, in_port_t sport, struct in_addr dst, in_port_t dport, const void *in, size_t dlen) { size_t l4len = dlen + sizeof(struct udphdr); - char buf[USHRT_MAX]; - struct iphdr *ip4h = tap_push_l2h(c, buf, ETH_P_IP); - struct udphdr *uh = tap_push_ip4h(ip4h, src, dst, l4len, IPPROTO_UDP); - char *data = (char *)(uh + 1); const struct iovec iov = { .iov_base = (void *)in, .iov_len = dlen @@ -190,8 +186,30 @@ void tap_udp4_send(const struct ctx *c, struct in_addr src, in_port_t sport, uh->dest = htons(dport); uh->len = htons(l4len); csum_udp4(uh, src, dst, &payload); - memcpy(data, in, dlen); + return uh + 1; +} + +/** + * tap_udp4_send() - Send UDP over IPv4 packet + * @c: Execution context + * @src: IPv4 source address + * @sport: UDP source port + * @dst: IPv4 destination address + * @dport: UDP destination port + * @in: UDP payload contents (not including UDP header) + * @dlen: UDP payload length (not including UDP header) + */ +void tap_udp4_send(const struct ctx *c, struct in_addr src, in_port_t sport, + struct in_addr dst, in_port_t dport, + const void *in, size_t dlen) +{ + size_t l4len = dlen + sizeof(struct udphdr); + char buf[USHRT_MAX]; + struct iphdr *ip4h = tap_push_l2h(c, buf, ETH_P_IP); + struct udphdr *uh = tap_push_ip4h(ip4h, src, dst, l4len, IPPROTO_UDP); + char *data = tap_push_uh4(uh, src, sport, dst, dport, in, dlen); + memcpy(data, in, dlen); tap_send_single(c, buf, dlen + (data - buf)); } diff --git a/tap.h b/tap.h index dfbd8b9..3451343 100644 --- a/tap.h +++ b/tap.h @@ -8,6 +8,8 @@ #define ETH_HDR_INIT(proto) { .h_proto = htons_constant(proto) } +struct udphdr; + /** * struct tap_hdr - tap backend specific headers * @vnet_len: Frame length (for qemu socket transport) @@ -43,7 +45,9 @@ static inline void tap_hdr_update(struct tap_hdr *thdr, size_t l2len) if (thdr) thdr->vnet_len = htonl(l2len); } - +void *tap_push_uh4(struct udphdr *uh, struct in_addr src, in_port_t sport, + struct in_addr dst, in_port_t dport, + const void *in, size_t dlen); void tap_udp4_send(const struct ctx *c, struct in_addr src, in_port_t sport, struct in_addr dst, in_port_t dport, const void *in, size_t dlen); -- 2.48.1