From 51149a2ac1ed962e04c48fe591f2b6b288755af6 Mon Sep 17 00:00:00 2001 From: Laurent Vivier Date: Mon, 27 Mar 2017 10:46:12 +0200 Subject: [PATCH 1/3] slirp: fix compilation errors with DEBUG set MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit slirp/slirp.c: In function 'get_dns_addr_resolv_conf': slirp/slirp.c:202:29: error: initialization discards 'const' qualifier from pointer target type [-Werror=discarded-qualifiers] char *res = inet_ntop(af, tmp_addr, s, sizeof(s)); ^~~~~~~~~ slirp/slirp.c:204:25: error: assignment discards 'const' qualifier from pointer target type [-Werror=discarded-qualifiers] res = "(string conversion error)"; Signed-off-by: Laurent Vivier Reviewed-by: Philippe Mathieu-Daudé Signed-off-by: Samuel Thibault --- slirp/slirp.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/slirp/slirp.c b/slirp/slirp.c index 60539de7a3..5a94b06f5e 100644 --- a/slirp/slirp.c +++ b/slirp/slirp.c @@ -198,7 +198,7 @@ static int get_dns_addr_resolv_conf(int af, void *pdns_addr, void *cached_addr, #ifdef DEBUG else { char s[INET6_ADDRSTRLEN]; - char *res = inet_ntop(af, tmp_addr, s, sizeof(s)); + const char *res = inet_ntop(af, tmp_addr, s, sizeof(s)); if (!res) { res = "(string conversion error)"; } From e42f869b5118fa9ac64dcea624276204567fc581 Mon Sep 17 00:00:00 2001 From: Samuel Thibault Date: Sun, 26 Mar 2017 20:28:11 +0200 Subject: [PATCH 2/3] slirp: Make RA build more flexible MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Do not hardcode the RA size at all, use a pl_size variable which accounts the accumulated size, and fill rip->ip_pl at the end. This will allow to make some blocks optional. Signed-off-by: Samuel Thibault Reviewed-by: Philippe Mathieu-Daudé --- slirp/ip6_icmp.c | 24 +++++++++--------------- 1 file changed, 9 insertions(+), 15 deletions(-) diff --git a/slirp/ip6_icmp.c b/slirp/ip6_icmp.c index 298a48dd25..d0f5cc1456 100644 --- a/slirp/ip6_icmp.c +++ b/slirp/ip6_icmp.c @@ -143,17 +143,10 @@ void ndp_send_ra(Slirp *slirp) /* Build IPv6 packet */ struct mbuf *t = m_get(slirp); struct ip6 *rip = mtod(t, struct ip6 *); + size_t pl_size = 0; rip->ip_src = (struct in6_addr)LINKLOCAL_ADDR; rip->ip_dst = (struct in6_addr)ALLNODES_MULTICAST; rip->ip_nh = IPPROTO_ICMPV6; - rip->ip_pl = htons(ICMP6_NDP_RA_MINLEN - + NDPOPT_LINKLAYER_LEN - + NDPOPT_PREFIXINFO_LEN -#ifndef _WIN32 - + NDPOPT_RDNSS_LEN -#endif - ); - t->m_len = sizeof(struct ip6) + ntohs(rip->ip_pl); /* Build ICMPv6 packet */ t->m_data += sizeof(struct ip6); @@ -171,6 +164,7 @@ void ndp_send_ra(Slirp *slirp) ricmp->icmp6_nra.reach_time = htonl(NDP_AdvReachableTime); ricmp->icmp6_nra.retrans_time = htonl(NDP_AdvRetransTime); t->m_data += ICMP6_NDP_RA_MINLEN; + pl_size += ICMP6_NDP_RA_MINLEN; /* Source link-layer address (NDP option) */ struct ndpopt *opt = mtod(t, struct ndpopt *); @@ -178,6 +172,7 @@ void ndp_send_ra(Slirp *slirp) opt->ndpopt_len = NDPOPT_LINKLAYER_LEN / 8; in6_compute_ethaddr(rip->ip_src, opt->ndpopt_linklayer); t->m_data += NDPOPT_LINKLAYER_LEN; + pl_size += NDPOPT_LINKLAYER_LEN; /* Prefix information (NDP option) */ struct ndpopt *opt2 = mtod(t, struct ndpopt *); @@ -192,6 +187,7 @@ void ndp_send_ra(Slirp *slirp) opt2->ndpopt_prefixinfo.reserved2 = 0; opt2->ndpopt_prefixinfo.prefix = slirp->vprefix_addr6; t->m_data += NDPOPT_PREFIXINFO_LEN; + pl_size += NDPOPT_PREFIXINFO_LEN; #ifndef _WIN32 /* Prefix information (NDP option) */ @@ -203,16 +199,14 @@ void ndp_send_ra(Slirp *slirp) opt3->ndpopt_rdnss.lifetime = htonl(2 * NDP_MaxRtrAdvInterval); opt3->ndpopt_rdnss.addr = slirp->vnameserver_addr6; t->m_data += NDPOPT_RDNSS_LEN; + pl_size += NDPOPT_RDNSS_LEN; #endif + rip->ip_pl = htons(pl_size); + t->m_data -= sizeof(struct ip6) + pl_size; + t->m_len = sizeof(struct ip6) + pl_size; + /* ICMPv6 Checksum */ -#ifndef _WIN32 - t->m_data -= NDPOPT_RDNSS_LEN; -#endif - t->m_data -= NDPOPT_PREFIXINFO_LEN; - t->m_data -= NDPOPT_LINKLAYER_LEN; - t->m_data -= ICMP6_NDP_RA_MINLEN; - t->m_data -= sizeof(struct ip6); ricmp->icmp6_cksum = ip6_cksum(t); ip6_output(NULL, t, 0); From a2f80fdfc683019901cdf4c0863a5920c0ca7245 Mon Sep 17 00:00:00 2001 From: Samuel Thibault Date: Sun, 26 Mar 2017 20:46:34 +0200 Subject: [PATCH 3/3] slirp: Send RDNSS in RA only if host has an IPv6 DNS server MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Previously we would always send an RDNSS option in the RA, making the guest try to resolve DNS through IPv6, even if the host does not actually have and IPv6 DNS server available. This makes the RDNSS option enabled only when an IPv6 DNS server is available. Signed-off-by: Samuel Thibault Reviewed-by: Philippe Mathieu-Daudé --- slirp/ip6_icmp.c | 25 ++++++++++++++----------- 1 file changed, 14 insertions(+), 11 deletions(-) diff --git a/slirp/ip6_icmp.c b/slirp/ip6_icmp.c index d0f5cc1456..777eb574be 100644 --- a/slirp/ip6_icmp.c +++ b/slirp/ip6_icmp.c @@ -144,6 +144,9 @@ void ndp_send_ra(Slirp *slirp) struct mbuf *t = m_get(slirp); struct ip6 *rip = mtod(t, struct ip6 *); size_t pl_size = 0; + struct in6_addr addr; + uint32_t scope_id; + rip->ip_src = (struct in6_addr)LINKLOCAL_ADDR; rip->ip_dst = (struct in6_addr)ALLNODES_MULTICAST; rip->ip_nh = IPPROTO_ICMPV6; @@ -189,18 +192,18 @@ void ndp_send_ra(Slirp *slirp) t->m_data += NDPOPT_PREFIXINFO_LEN; pl_size += NDPOPT_PREFIXINFO_LEN; -#ifndef _WIN32 /* Prefix information (NDP option) */ - /* disabled for windows for now, until get_dns6_addr is implemented */ - struct ndpopt *opt3 = mtod(t, struct ndpopt *); - opt3->ndpopt_type = NDPOPT_RDNSS; - opt3->ndpopt_len = NDPOPT_RDNSS_LEN / 8; - opt3->ndpopt_rdnss.reserved = 0; - opt3->ndpopt_rdnss.lifetime = htonl(2 * NDP_MaxRtrAdvInterval); - opt3->ndpopt_rdnss.addr = slirp->vnameserver_addr6; - t->m_data += NDPOPT_RDNSS_LEN; - pl_size += NDPOPT_RDNSS_LEN; -#endif + if (get_dns6_addr(&addr, &scope_id) >= 0) { + /* Host system does have an IPv6 DNS server, announce our proxy. */ + struct ndpopt *opt3 = mtod(t, struct ndpopt *); + opt3->ndpopt_type = NDPOPT_RDNSS; + opt3->ndpopt_len = NDPOPT_RDNSS_LEN / 8; + opt3->ndpopt_rdnss.reserved = 0; + opt3->ndpopt_rdnss.lifetime = htonl(2 * NDP_MaxRtrAdvInterval); + opt3->ndpopt_rdnss.addr = slirp->vnameserver_addr6; + t->m_data += NDPOPT_RDNSS_LEN; + pl_size += NDPOPT_RDNSS_LEN; + } rip->ip_pl = htons(pl_size); t->m_data -= sizeof(struct ip6) + pl_size;