The INADDR_LOOPBACK constant is in host endianness, and similarly the IN_MULTICAST macro expects a host endian address. However, there are some places in passt where we use those with network endian values. This means that passt will incorrectly allow you to set 127.0.0.1 or a multicast address as the guest address or DNS forwarding address. Add the necessary conversions to correct this. INADDR_ANY and INADDR_BROADCAST logically behave the same way, although because they're palindromes it doesn't have an effect in practice. Change them to be logically correct while we're there, though. Signed-off-by: David Gibson <david(a)gibson.dropbear.id.au> --- conf.c | 26 +++++++++++++------------- icmp.c | 2 +- 2 files changed, 14 insertions(+), 14 deletions(-) diff --git a/conf.c b/conf.c index 598c711..769df97 100644 --- a/conf.c +++ b/conf.c @@ -1164,11 +1164,11 @@ void conf(struct ctx *c, int argc, char **argv) !IN6_IS_ADDR_LOOPBACK(&c->ip6.dns_fwd)) break; - if (c->ip4.dns_fwd == INADDR_ANY && + if (c->ip4.dns_fwd == htonl(INADDR_ANY) && inet_pton(AF_INET, optarg, &c->ip4.dns_fwd) && - c->ip4.dns_fwd != INADDR_ANY && - c->ip4.dns_fwd != INADDR_BROADCAST && - c->ip4.dns_fwd != INADDR_LOOPBACK) + c->ip4.dns_fwd != htonl(INADDR_ANY) && + c->ip4.dns_fwd != htonl(INADDR_BROADCAST) && + c->ip4.dns_fwd != htonl(INADDR_LOOPBACK)) break; err("Invalid DNS forwarding address: %s", optarg); @@ -1363,12 +1363,12 @@ void conf(struct ctx *c, int argc, char **argv) !IN6_IS_ADDR_MULTICAST(&c->ip6.addr)) break; - if (c->ip4.addr == INADDR_ANY && + if (c->ip4.addr == htonl(INADDR_ANY) && inet_pton(AF_INET, optarg, &c->ip4.addr) && - c->ip4.addr != INADDR_ANY && - c->ip4.addr != INADDR_BROADCAST && - c->ip4.addr != INADDR_LOOPBACK && - !IN_MULTICAST(c->ip4.addr)) + c->ip4.addr != htonl(INADDR_ANY) && + c->ip4.addr != htonl(INADDR_BROADCAST) && + c->ip4.addr != htonl(INADDR_LOOPBACK) && + !IN_MULTICAST(ntohl(c->ip4.addr))) break; err("Invalid address: %s", optarg); @@ -1406,11 +1406,11 @@ void conf(struct ctx *c, int argc, char **argv) !IN6_IS_ADDR_LOOPBACK(&c->ip6.gw)) break; - if (c->ip4.gw == INADDR_ANY && + if (c->ip4.gw == htonl(INADDR_ANY) && inet_pton(AF_INET, optarg, &c->ip4.gw) && - c->ip4.gw != INADDR_ANY && - c->ip4.gw != INADDR_BROADCAST && - c->ip4.gw != INADDR_LOOPBACK) + c->ip4.gw != htonl(INADDR_ANY) && + c->ip4.gw != htonl(INADDR_BROADCAST) && + c->ip4.gw != htonl(INADDR_LOOPBACK)) break; err("Invalid gateway address: %s", optarg); diff --git a/icmp.c b/icmp.c index 233acf9..125f314 100644 --- a/icmp.c +++ b/icmp.c @@ -148,7 +148,7 @@ int icmp_tap_handler(const struct ctx *c, int af, const void *addr, union icmp_epoll_ref iref = { .icmp.v6 = 0 }; struct sockaddr_in sa = { .sin_family = AF_INET, - .sin_addr = { .s_addr = INADDR_ANY }, + .sin_addr = { .s_addr = htonl(INADDR_ANY) }, }; struct icmphdr *ih; int id, s; -- 2.38.1