From bf19154051b6c920f702c8394cd6821bb00f531a Mon Sep 17 00:00:00 2001 From: Stefano Brivio Date: Thu, 23 Feb 2023 13:32:30 +0000 Subject: [PATCH 02/20] conf: Split add_dns{4,6}() out of get_dns() The logic handling which resolvers we add, and whether to add them, is getting rather cramped in get_dns(): split it into separate functions. No functional changes intended. Signed-off-by: Stefano Brivio Tested-by: Andrea Bolognani Reviewed-by: David Gibson (cherry picked from commit 8ca907a3f0a095691cdaf56ad610fd802df88146) --- conf.c | 86 ++++++++++++++++++++++++++++++++++------------------------ 1 file changed, 51 insertions(+), 35 deletions(-) diff --git a/conf.c b/conf.c index 4dc0660..ed25e35 100644 --- a/conf.c +++ b/conf.c @@ -382,6 +382,53 @@ bind_fail: die("Failed to bind any port for '-%c %s', exiting", optname, optarg); } +/** + * add_dns4() - Possibly add the IPv4 address of a DNS resolver to configuration + * @c: Execution context + * @addr: Address found in /etc/resolv.conf + * @conf: Pointer to reference of current entry in array of IPv4 resolvers + */ +static void add_dns4(struct ctx *c, struct in_addr *addr, struct in_addr **conf) +{ + /* Guest or container can only access local addresses via redirect */ + if (IN4_IS_ADDR_LOOPBACK(addr)) { + if (!c->no_map_gw) { + **conf = c->ip4.gw; + (*conf)++; + } + } else { + **conf = *addr; + (*conf)++; + } + + if (IN4_IS_ADDR_UNSPECIFIED(&c->ip4.dns_host)) + c->ip4.dns_host = *addr; +} + +/** + * add_dns6() - Possibly add the IPv6 address of a DNS resolver to configuration + * @c: Execution context + * @addr: Address found in /etc/resolv.conf + * @conf: Pointer to reference of current entry in array of IPv6 resolvers + */ +static void add_dns6(struct ctx *c, + struct in6_addr *addr, struct in6_addr **conf) +{ + /* Guest or container can only access local addresses via redirect */ + if (IN6_IS_ADDR_LOOPBACK(addr)) { + if (!c->no_map_gw) { + memcpy(*conf, &c->ip6.gw, sizeof(**conf)); + (*conf)++; + } + } else { + memcpy(*conf, addr, sizeof(**conf)); + (*conf)++; + } + + if (IN6_IS_ADDR_UNSPECIFIED(&c->ip6.dns_host)) + c->ip6.dns_host = *addr; +} + /** * get_dns() - Get nameserver addresses from local /etc/resolv.conf * @c: Execution context @@ -420,44 +467,13 @@ static void get_dns(struct ctx *c) if (!dns4_set && dns4 - &c->ip4.dns[0] < ARRAY_SIZE(c->ip4.dns) - 1 - && inet_pton(AF_INET, p + 1, &dns4_tmp)) { - /* Guest or container can only access local - * addresses via local redirect - */ - if (IN4_IS_ADDR_LOOPBACK(&dns4_tmp)) { - if (!c->no_map_gw) { - *dns4 = c->ip4.gw; - dns4++; - } - } else { - *dns4 = dns4_tmp; - dns4++; - } - - if (IN4_IS_ADDR_UNSPECIFIED(&c->ip4.dns_host)) - c->ip4.dns_host = dns4_tmp; - } + && inet_pton(AF_INET, p + 1, &dns4_tmp)) + add_dns4(c, &dns4_tmp, &dns4); if (!dns6_set && dns6 - &c->ip6.dns[0] < ARRAY_SIZE(c->ip6.dns) - 1 - && inet_pton(AF_INET6, p + 1, &dns6_tmp)) { - /* Guest or container can only access local - * addresses via local redirect - */ - if (IN6_IS_ADDR_LOOPBACK(&dns6_tmp)) { - if (!c->no_map_gw) { - memcpy(dns6, &c->ip6.gw, - sizeof(*dns6)); - dns6++; - } - } else { - memcpy(dns6, &dns6_tmp, sizeof(*dns6)); - dns6++; - } - - if (IN6_IS_ADDR_UNSPECIFIED(&c->ip6.dns_host)) - c->ip6.dns_host = dns6_tmp; - } + && inet_pton(AF_INET6, p + 1, &dns6_tmp)) + add_dns6(c, &dns6_tmp, &dns6); } else if (!dnss_set && strstr(line, "search ") == line && s == c->dns_search) { end = strpbrk(line, "\n"); -- 2.39.2