From: Stefano Brivio <sbrivio@redhat.com>
To: passt-dev@passt.top
Cc: Andrew Sayers <andrew-bugs.passt.top@pileofstuff.org>,
Paul Holzinger <pholzing@redhat.com>,
David Gibson <david@gibson.dropbear.id.au>
Subject: [PATCH 1/2] conf: Split add_dns_resolv() into separate IPv4 and IPv6 versions
Date: Fri, 11 Apr 2025 11:14:38 +0200 [thread overview]
Message-ID: <20250411091439.2943014-2-sbrivio@redhat.com> (raw)
In-Reply-To: <20250411091439.2943014-1-sbrivio@redhat.com>
Not really valuable by itself, but dropping one level of nested blocks
makes the next change more convenient.
No functional changes intended.
Signed-off-by: Stefano Brivio <sbrivio@redhat.com>
---
conf.c | 101 ++++++++++++++++++++++++++++++++++-----------------------
1 file changed, 60 insertions(+), 41 deletions(-)
diff --git a/conf.c b/conf.c
index 168646f..18ed11c 100644
--- a/conf.c
+++ b/conf.c
@@ -414,6 +414,62 @@ static unsigned add_dns6(struct ctx *c, const struct in6_addr *addr,
return 1;
}
+/**
+ * add_dns_resolv4() - Possibly add one IPv4 nameserver from host's resolv.conf
+ * @c: Execution context
+ * @ns: Nameserver address
+ * @idx: Pointer to index of current IPv4 resolver entry, set on return
+ */
+static void add_dns_resolv4(struct ctx *c, struct in_addr *ns, unsigned *idx)
+{
+ if (IN4_IS_ADDR_UNSPECIFIED(&c->ip4.dns_host))
+ c->ip4.dns_host = *ns;
+
+ /* Special handling if guest or container can only access local
+ * addresses via redirect, or if the host gateway is also a resolver and
+ * we shadow its address
+ */
+ if (IN4_IS_ADDR_LOOPBACK(ns) ||
+ IN4_ARE_ADDR_EQUAL(ns, &c->ip4.map_host_loopback)) {
+ if (IN4_IS_ADDR_UNSPECIFIED(&c->ip4.map_host_loopback))
+ return;
+
+ *ns = c->ip4.map_host_loopback;
+ if (IN4_IS_ADDR_UNSPECIFIED(&c->ip4.dns_match))
+ c->ip4.dns_match = c->ip4.map_host_loopback;
+ }
+
+ *idx += add_dns4(c, ns, *idx);
+}
+
+/**
+ * add_dns_resolv6() - Possibly add one IPv6 nameserver from host's resolv.conf
+ * @c: Execution context
+ * @ns: Nameserver address
+ * @idx: Pointer to index of current IPv6 resolver entry, set on return
+ */
+static void add_dns_resolv6(struct ctx *c, struct in6_addr *ns, unsigned *idx)
+{
+ if (IN6_IS_ADDR_UNSPECIFIED(&c->ip6.dns_host))
+ c->ip6.dns_host = *ns;
+
+ /* Special handling if guest or container can only access local
+ * addresses via redirect, or if the host gateway is also a resolver and
+ * we shadow its address
+ */
+ if (IN6_IS_ADDR_LOOPBACK(ns) ||
+ IN6_ARE_ADDR_EQUAL(ns, &c->ip6.map_host_loopback)) {
+ if (IN6_IS_ADDR_UNSPECIFIED(&c->ip6.map_host_loopback))
+ return;
+
+ *ns = c->ip6.map_host_loopback;
+ if (IN6_IS_ADDR_UNSPECIFIED(&c->ip6.dns_match))
+ c->ip6.dns_match = c->ip6.map_host_loopback;
+ }
+
+ *idx += add_dns6(c, ns, *idx);
+}
+
/**
* add_dns_resolv() - Possibly add ns from host resolv.conf to configuration
* @c: Execution context
@@ -430,48 +486,11 @@ static void add_dns_resolv(struct ctx *c, const char *nameserver,
struct in6_addr ns6;
struct in_addr ns4;
- if (idx4 && inet_pton(AF_INET, nameserver, &ns4)) {
- if (IN4_IS_ADDR_UNSPECIFIED(&c->ip4.dns_host))
- c->ip4.dns_host = ns4;
-
- /* Special handling if guest or container can only access local
- * addresses via redirect, or if the host gateway is also a
- * resolver and we shadow its address
- */
- if (IN4_IS_ADDR_LOOPBACK(&ns4) ||
- IN4_ARE_ADDR_EQUAL(&ns4, &c->ip4.map_host_loopback)) {
- if (IN4_IS_ADDR_UNSPECIFIED(&c->ip4.map_host_loopback))
- return;
-
- ns4 = c->ip4.map_host_loopback;
- if (IN4_IS_ADDR_UNSPECIFIED(&c->ip4.dns_match))
- c->ip4.dns_match = c->ip4.map_host_loopback;
- }
-
- *idx4 += add_dns4(c, &ns4, *idx4);
- }
-
- if (idx6 && inet_pton(AF_INET6, nameserver, &ns6)) {
- if (IN6_IS_ADDR_UNSPECIFIED(&c->ip6.dns_host))
- c->ip6.dns_host = ns6;
-
- /* Special handling if guest or container can only access local
- * addresses via redirect, or if the host gateway is also a
- * resolver and we shadow its address
- */
- if (IN6_IS_ADDR_LOOPBACK(&ns6) ||
- IN6_ARE_ADDR_EQUAL(&ns6, &c->ip6.map_host_loopback)) {
- if (IN6_IS_ADDR_UNSPECIFIED(&c->ip6.map_host_loopback))
- return;
+ if (idx4 && inet_pton(AF_INET, nameserver, &ns4))
+ add_dns_resolv4(c, &ns4, idx4);
- ns6 = c->ip6.map_host_loopback;
-
- if (IN6_IS_ADDR_UNSPECIFIED(&c->ip6.dns_match))
- c->ip6.dns_match = c->ip6.map_host_loopback;
- }
-
- *idx6 += add_dns6(c, &ns6, *idx6);
- }
+ if (idx6 && inet_pton(AF_INET6, nameserver, &ns6))
+ add_dns_resolv6(c, &ns6, idx6);
}
/**
--
@@ -414,6 +414,62 @@ static unsigned add_dns6(struct ctx *c, const struct in6_addr *addr,
return 1;
}
+/**
+ * add_dns_resolv4() - Possibly add one IPv4 nameserver from host's resolv.conf
+ * @c: Execution context
+ * @ns: Nameserver address
+ * @idx: Pointer to index of current IPv4 resolver entry, set on return
+ */
+static void add_dns_resolv4(struct ctx *c, struct in_addr *ns, unsigned *idx)
+{
+ if (IN4_IS_ADDR_UNSPECIFIED(&c->ip4.dns_host))
+ c->ip4.dns_host = *ns;
+
+ /* Special handling if guest or container can only access local
+ * addresses via redirect, or if the host gateway is also a resolver and
+ * we shadow its address
+ */
+ if (IN4_IS_ADDR_LOOPBACK(ns) ||
+ IN4_ARE_ADDR_EQUAL(ns, &c->ip4.map_host_loopback)) {
+ if (IN4_IS_ADDR_UNSPECIFIED(&c->ip4.map_host_loopback))
+ return;
+
+ *ns = c->ip4.map_host_loopback;
+ if (IN4_IS_ADDR_UNSPECIFIED(&c->ip4.dns_match))
+ c->ip4.dns_match = c->ip4.map_host_loopback;
+ }
+
+ *idx += add_dns4(c, ns, *idx);
+}
+
+/**
+ * add_dns_resolv6() - Possibly add one IPv6 nameserver from host's resolv.conf
+ * @c: Execution context
+ * @ns: Nameserver address
+ * @idx: Pointer to index of current IPv6 resolver entry, set on return
+ */
+static void add_dns_resolv6(struct ctx *c, struct in6_addr *ns, unsigned *idx)
+{
+ if (IN6_IS_ADDR_UNSPECIFIED(&c->ip6.dns_host))
+ c->ip6.dns_host = *ns;
+
+ /* Special handling if guest or container can only access local
+ * addresses via redirect, or if the host gateway is also a resolver and
+ * we shadow its address
+ */
+ if (IN6_IS_ADDR_LOOPBACK(ns) ||
+ IN6_ARE_ADDR_EQUAL(ns, &c->ip6.map_host_loopback)) {
+ if (IN6_IS_ADDR_UNSPECIFIED(&c->ip6.map_host_loopback))
+ return;
+
+ *ns = c->ip6.map_host_loopback;
+ if (IN6_IS_ADDR_UNSPECIFIED(&c->ip6.dns_match))
+ c->ip6.dns_match = c->ip6.map_host_loopback;
+ }
+
+ *idx += add_dns6(c, ns, *idx);
+}
+
/**
* add_dns_resolv() - Possibly add ns from host resolv.conf to configuration
* @c: Execution context
@@ -430,48 +486,11 @@ static void add_dns_resolv(struct ctx *c, const char *nameserver,
struct in6_addr ns6;
struct in_addr ns4;
- if (idx4 && inet_pton(AF_INET, nameserver, &ns4)) {
- if (IN4_IS_ADDR_UNSPECIFIED(&c->ip4.dns_host))
- c->ip4.dns_host = ns4;
-
- /* Special handling if guest or container can only access local
- * addresses via redirect, or if the host gateway is also a
- * resolver and we shadow its address
- */
- if (IN4_IS_ADDR_LOOPBACK(&ns4) ||
- IN4_ARE_ADDR_EQUAL(&ns4, &c->ip4.map_host_loopback)) {
- if (IN4_IS_ADDR_UNSPECIFIED(&c->ip4.map_host_loopback))
- return;
-
- ns4 = c->ip4.map_host_loopback;
- if (IN4_IS_ADDR_UNSPECIFIED(&c->ip4.dns_match))
- c->ip4.dns_match = c->ip4.map_host_loopback;
- }
-
- *idx4 += add_dns4(c, &ns4, *idx4);
- }
-
- if (idx6 && inet_pton(AF_INET6, nameserver, &ns6)) {
- if (IN6_IS_ADDR_UNSPECIFIED(&c->ip6.dns_host))
- c->ip6.dns_host = ns6;
-
- /* Special handling if guest or container can only access local
- * addresses via redirect, or if the host gateway is also a
- * resolver and we shadow its address
- */
- if (IN6_IS_ADDR_LOOPBACK(&ns6) ||
- IN6_ARE_ADDR_EQUAL(&ns6, &c->ip6.map_host_loopback)) {
- if (IN6_IS_ADDR_UNSPECIFIED(&c->ip6.map_host_loopback))
- return;
+ if (idx4 && inet_pton(AF_INET, nameserver, &ns4))
+ add_dns_resolv4(c, &ns4, idx4);
- ns6 = c->ip6.map_host_loopback;
-
- if (IN6_IS_ADDR_UNSPECIFIED(&c->ip6.dns_match))
- c->ip6.dns_match = c->ip6.map_host_loopback;
- }
-
- *idx6 += add_dns6(c, &ns6, *idx6);
- }
+ if (idx6 && inet_pton(AF_INET6, nameserver, &ns6))
+ add_dns_resolv6(c, &ns6, idx6);
}
/**
--
2.43.0
next prev parent reply other threads:[~2025-04-11 9:14 UTC|newest]
Thread overview: 6+ messages / expand[flat|nested] mbox.gz Atom feed top
2025-04-11 9:14 [PATCH 0/2] Fix --dns-forward with --no-map-gw Stefano Brivio
2025-04-11 9:14 ` Stefano Brivio [this message]
2025-04-14 2:05 ` [PATCH 1/2] conf: Split add_dns_resolv() into separate IPv4 and IPv6 versions David Gibson
2025-04-11 9:14 ` [PATCH 2/2] conf: Honour --dns-forward for local resolver even with --no-map-gw Stefano Brivio
2025-04-14 2:07 ` David Gibson
2025-04-11 15:14 ` [PATCH 0/2] Fix --dns-forward " Paul Holzinger
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