diff options
| -rw-r--r-- | fwd.c | 41 | ||||
| -rw-r--r-- | inany.h | 2 |
2 files changed, 29 insertions, 14 deletions
@@ -1006,6 +1006,24 @@ bool nat_inbound(const struct ctx *c, const union inany_addr *addr, } /** + * fwd_default_guest_addr() - Get appropriate guest address to send to + * @c: Execution context + * @template: Address to match IP version and scope of + * + * Return: the address of the guest, which best matches the IP version and scope + * of @template + */ +static union inany_addr fwd_default_guest_addr(const struct ctx *c, + const union inany_addr *template) +{ + if (inany_v4(template)) + return inany_from_v4(c->ip4.addr_seen); + if (inany_is_linklocal6(template)) + return inany_from_v6(c->ip6.addr_ll_seen); + return inany_from_v6(c->ip6.addr_seen); +} + +/** * fwd_nat_from_host() - Determine to forward a flow from the host interface * @c: Execution context * @rule: Forwarding rule to apply @@ -1040,13 +1058,9 @@ uint8_t fwd_nat_from_host(const struct ctx *c, */ if (c->host_lo_to_ns_lo && inany_is_loopback(&ini->oaddr)) tgt->eaddr = ini->oaddr; - else if (inany_v4(&ini->eaddr)) - tgt->eaddr = inany_from_v4(c->ip4.addr_seen); - else - tgt->eaddr.a6 = c->ip6.addr_seen; /* Let the kernel pick source address and port */ - if (inany_v4(&tgt->eaddr)) + if (inany_v4(&ini->eaddr)) tgt->oaddr = inany_any4; else tgt->oaddr = inany_any6; @@ -1056,6 +1070,9 @@ uint8_t fwd_nat_from_host(const struct ctx *c, /* But for UDP preserve the source port */ tgt->oport = ini->eport; + /* Use guest address as destination, if otherwise unspecified */ + if (inany_is_unspecified(&tgt->eaddr)) + tgt->eaddr = fwd_default_guest_addr(c, &tgt->oaddr); return PIF_SPLICE; } @@ -1074,16 +1091,12 @@ uint8_t fwd_nat_from_host(const struct ctx *c, } tgt->oport = ini->eport; - if (!inany_is_unspecified(&rule->taddr)) { + if (!inany_is_unspecified(&rule->taddr)) tgt->eaddr = rule->taddr; - } else if (inany_v4(&tgt->oaddr)) { - tgt->eaddr = inany_from_v4(c->ip4.addr_seen); - } else { - if (inany_is_linklocal6(&tgt->oaddr)) - tgt->eaddr.a6 = c->ip6.addr_ll_seen; - else - tgt->eaddr.a6 = c->ip6.addr_seen; - } + + /* Use guest address as destination, if otherwise unspecified */ + if (inany_is_unspecified(&tgt->eaddr)) + tgt->eaddr = fwd_default_guest_addr(c, &tgt->oaddr); return PIF_TAP; } @@ -59,6 +59,8 @@ extern const union inany_addr inany_any4; #define inany_from_v4(a4) \ ((union inany_addr)INANY_INIT4((a4))) +#define inany_from_v6(a6_) \ + ((union inany_addr){.a6 = (a6_)}) /** union sockaddr_inany - Either a sockaddr_in or a sockaddr_in6 * @sa_family: Address family, AF_INET or AF_INET6 |