From mboxrd@z Thu Jan 1 00:00:00 1970 Authentication-Results: passt.top; dmarc=pass (p=quarantine 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=d4FR8vub; 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 135815A061D for ; Mon, 13 Apr 2026 02:53:31 +0200 (CEST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1776041610; 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=sMOmuai5tkRgu+/gCnwyaOzckW8uTXoEhZRfrR1HSr8=; b=d4FR8vubupwOT2s/e6mDyHulr6/1KE026OuXSB68DIHlYN2ZL47d0mpeU2amIQTFt/QfOr FNv8Dbe2JxwRoaOQ8xe/v6DkBEB6mNCWMiYjnjpnJKx94s3BulPXkvMrUWRyTtHXACv1qW dG6XJQ8hiOreQwjfBA4hrFnY7qfe8HU= Received: from mx-prod-mc-08.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-267-kVU5pgWsO8a7yUijd-3SIQ-1; Sun, 12 Apr 2026 20:53:29 -0400 X-MC-Unique: kVU5pgWsO8a7yUijd-3SIQ-1 X-Mimecast-MFC-AGG-ID: kVU5pgWsO8a7yUijd-3SIQ_1776041608 Received: from mx-prod-int-01.mail-002.prod.us-west-2.aws.redhat.com (mx-prod-int-01.mail-002.prod.us-west-2.aws.redhat.com [10.30.177.4]) (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-08.mail-002.prod.us-west-2.aws.redhat.com (Postfix) with ESMTPS id 556A21800371; Mon, 13 Apr 2026 00:53:28 +0000 (UTC) Received: from jmaloy-thinkpadp16vgen1.rmtcaqc.csb (unknown [10.22.64.70]) by mx-prod-int-01.mail-002.prod.us-west-2.aws.redhat.com (Postfix) with ESMTP id 9712230001A1; Mon, 13 Apr 2026 00:53:27 +0000 (UTC) From: Jon Maloy To: sbrivio@redhat.com, david@gibson.dropbear.id.au, jmaloy@redhat.com, passt-dev@passt.top Subject: [PATCH v7 06/13] netlink, conf: Read all addresses from template interface at startup Date: Sun, 12 Apr 2026 20:53:12 -0400 Message-ID: <20260413005319.3295910-7-jmaloy@redhat.com> In-Reply-To: <20260413005319.3295910-1-jmaloy@redhat.com> References: <20260413005319.3295910-1-jmaloy@redhat.com> MIME-Version: 1.0 X-Scanned-By: MIMEDefang 3.4.1 on 10.30.177.4 X-Mimecast-Spam-Score: 0 X-Mimecast-MFC-PROC-ID: yyyfg5aoFqXrVaDw8x0Ra5ZiUbm8E1md7jpl7wZ5SUw_1776041608 X-Mimecast-Originator: redhat.com Content-Transfer-Encoding: 8bit content-type: text/plain; charset="US-ASCII"; x-default=true Message-ID-Hash: MUM27LWNPSFJ3XHYZX4YALZYGDJUV2Z3 X-Message-ID-Hash: MUM27LWNPSFJ3XHYZX4YALZYGDJUV2Z3 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: Add nl_addr_get_all() to read all addresses from the template interface into c->addrs[] array, rather than just selecting the "best" one. This allows multi-address configurations where the template interface has multiple IPv4 or IPv6 addresses assigned to it, all of which will now be copied to the guest namespace when using --config-net. For IPv6, the function also captures the link-local address into c->ip6.our_tap_ll as a side effect. Update conf_ip4() and conf_ip6() to use nl_addr_get_all() when no user-specified addresses are present. Signed-off-by: Jon Maloy Reviewed-by: David Gibson --- v7: -Excluded all link local addresses from host to be added to array -Minor comment change suggested by Stefano --- conf.c | 51 ++++++++++++++++++++++++++------------------------- netlink.c | 53 +++++++++++++++++++++++++++++------------------------ netlink.h | 3 +-- 3 files changed, 56 insertions(+), 51 deletions(-) diff --git a/conf.c b/conf.c index 8b4a7a0..924ade2 100644 --- a/conf.c +++ b/conf.c @@ -736,6 +736,7 @@ static int conf_ip4_prefix(const char *arg) static unsigned int conf_ip4(struct ctx *c, unsigned int ifi) { struct ip4_ctx *ip4 = &c->ip4; + const struct guest_addr *a; if (!ifi) ifi = nl_get_ext_if(nl_sock, AF_INET); @@ -755,24 +756,24 @@ static unsigned int conf_ip4(struct ctx *c, unsigned int ifi) } } - if (!fwd_get_addr(c, AF_INET, 0, 0)) { - struct in_addr addr; - int prefix_len; - int rc = nl_addr_get(nl_sock, ifi, AF_INET, - &addr, &prefix_len, NULL); + a = fwd_get_addr(c, AF_INET, CONF_ADDR_USER, 0); + if (!a) { + int rc = nl_addr_get_all(c, nl_sock, ifi, AF_INET); + if (rc < 0) { - debug("Couldn't discover IPv4 address: %s", + debug("Couldn't discover IPv4 addresses: %s", strerror_(-rc)); return 0; } - if (IN4_IS_ADDR_UNSPECIFIED(&addr)) + if (!rc || !fwd_get_addr(c, AF_INET, 0, 0)) return 0; - fwd_set_addr(c, &inany_from_v4(addr), CONF_ADDR_HOST, - prefix_len); - ip4->addr_seen = addr; + a = fwd_get_addr(c, AF_INET, CONF_ADDR_HOST, 0); } + if (a) + ip4->addr_seen = *inany_v4(&a->addr); + ip4->our_tap_addr = ip4->guest_gw; return ifi; @@ -805,8 +806,6 @@ static unsigned int conf_ip6(struct ctx *c, unsigned int ifi) { struct ip6_ctx *ip6 = &c->ip6; const struct guest_addr *a; - union inany_addr addr; - int prefix_len = 0; int rc; if (!ifi) @@ -826,24 +825,26 @@ static unsigned int conf_ip6(struct ctx *c, unsigned int ifi) } } - rc = nl_addr_get(nl_sock, ifi, AF_INET6, &addr.a6, - &prefix_len, &ip6->our_tap_ll); - if (rc < 0) { - debug("Couldn't discover IPv6 address: %s", strerror_(-rc)); - return 0; - } - - a = fwd_get_addr(c, AF_INET6, 0, 0); + a = fwd_get_addr(c, AF_INET6, CONF_ADDR_USER, 0); if (!a) { - if (IN6_IS_ADDR_UNSPECIFIED(&addr)) + rc = nl_addr_get_all(c, nl_sock, ifi, AF_INET6); + if (rc < 0) { + debug("Couldn't discover IPv6 addresses: %s", + strerror_(-rc)); return 0; - - fwd_set_addr(c, &addr, CONF_ADDR_HOST, prefix_len); - ip6->addr_seen = addr.a6; + } + a = fwd_get_addr(c, AF_INET6, CONF_ADDR_HOST, 0); } else { - ip6->addr_seen = a->addr.a6; + rc = nl_addr_get_ll(nl_sock, ifi, &ip6->our_tap_ll); + if (rc < 0) { + debug("Couldn't get link-local address: %s", + strerror_(-rc)); + } } + if (a) + ip6->addr_seen = a->addr.a6; + if (IN6_IS_ADDR_LINKLOCAL(&ip6->guest_gw)) ip6->our_tap_ll = ip6->guest_gw; diff --git a/netlink.c b/netlink.c index e07b47f..3f5a812 100644 --- a/netlink.c +++ b/netlink.c @@ -747,20 +747,20 @@ int nl_addr_set_ll_nodad(int s, unsigned int ifi) } /** - * nl_addr_get() - Get most specific global address, given interface and family + * nl_addr_get_all() - Get all addresses for a given interface into ctx + * @c: Execution context * @s: Netlink socket - * @ifi: Interface index in outer network namespace - * @af: Address family - * @addr: Global address to fill - * @prefix_len: Mask or prefix length, to fill - * @addr_l: Link-scoped address to fill (for IPv6) + * @ifi: Interface index + * @af: Address family (AF_INET or AF_INET6) * - * Return: 0 on success, negative error code on failure + * Populates c->addrs[] with all non-deprecated addresses from the interface. + * For IPv6, also captures link-local address in c->ip6.our_tap_ll. + * Skips IPv6 link-local addresses for the main array. + * + * Return: number of addresses added, or negative error code on failure */ -int nl_addr_get(int s, unsigned int ifi, sa_family_t af, - void *addr, int *prefix_len, void *addr_l) +int nl_addr_get_all(struct ctx *c, int s, unsigned int ifi, sa_family_t af) { - uint8_t prefix_max = 0, prefix_max_ll = 0; struct req_t { struct nlmsghdr nlh; struct ifaddrmsg ifa; @@ -771,6 +771,7 @@ int nl_addr_get(int s, unsigned int ifi, sa_family_t af, struct nlmsghdr *nh; char buf[NLBUFSIZ]; ssize_t status; + int count = 0; uint32_t seq; seq = nl_send(s, &req, RTM_GETADDR, NLM_F_DUMP, sizeof(req)); @@ -784,27 +785,31 @@ int nl_addr_get(int s, unsigned int ifi, sa_family_t af, for (rta = IFA_RTA(ifa), na = IFA_PAYLOAD(nh); RTA_OK(rta, na); rta = RTA_NEXT(rta, na)) { - if ((af == AF_INET && rta->rta_type != IFA_LOCAL) || - (af == AF_INET6 && rta->rta_type != IFA_ADDRESS)) - continue; + union inany_addr addr; - if (ifa->ifa_prefixlen > prefix_max && addr && - (af == AF_INET || ifa->ifa_scope < RT_SCOPE_LINK)) { - memcpy(addr, RTA_DATA(rta), RTA_PAYLOAD(rta)); + if (af == AF_INET && rta->rta_type != IFA_LOCAL) + continue; + if (af == AF_INET6 && rta->rta_type != IFA_ADDRESS) + continue; - prefix_max = *prefix_len = ifa->ifa_prefixlen; + /* Skip link-local addresses (kernel auto-configures) */ + if (ifa->ifa_scope == RT_SCOPE_LINK) { + if (af == AF_INET) + continue; + memcpy(&c->ip6.our_tap_ll, RTA_DATA(rta), + sizeof(c->ip6.our_tap_ll)); + continue; } - if (addr_l && - af == AF_INET6 && ifa->ifa_scope == RT_SCOPE_LINK && - ifa->ifa_prefixlen > prefix_max_ll) { - memcpy(addr_l, RTA_DATA(rta), RTA_PAYLOAD(rta)); + inany_from_af(&addr, af, RTA_DATA(rta)); + fwd_set_addr(c, &addr, CONF_ADDR_HOST, + ifa->ifa_prefixlen); - prefix_max_ll = ifa->ifa_prefixlen; - } + count++; } } - return status; + + return status < 0 ? status : count; } /** diff --git a/netlink.h b/netlink.h index b22f485..3af6d58 100644 --- a/netlink.h +++ b/netlink.h @@ -19,8 +19,7 @@ int nl_route_get_def(int s, unsigned int ifi, sa_family_t af, void *gw); int nl_route_set_def(int s, unsigned int ifi, sa_family_t af, const void *gw); int nl_route_dup(int s_src, unsigned int ifi_src, int s_dst, unsigned int ifi_dst, sa_family_t af); -int nl_addr_get(int s, unsigned int ifi, sa_family_t af, - void *addr, int *prefix_len, void *addr_l); +int nl_addr_get_all(struct ctx *c, int s, unsigned int ifi, sa_family_t af); bool nl_neigh_mac_get(int s, const union inany_addr *addr, int ifi, unsigned char *mac); int nl_addr_set(int s, unsigned int ifi, sa_family_t af, -- 2.52.0