diff options
Diffstat (limited to 'conf.c')
| -rw-r--r-- | conf.c | 11 |
1 files changed, 7 insertions, 4 deletions
@@ -1434,6 +1434,7 @@ void conf(struct ctx *c, int argc, char **argv) enum fwd_ports_mode fwd_default = FWD_NONE; bool v4_only = false, v6_only = false; unsigned dns4_idx = 0, dns6_idx = 0; + unsigned long max_mtu = IP_MAX_MTU; struct fqdn *dnss = c->dns_search; unsigned int ifi4 = 0, ifi6 = 0; const char *logfile = NULL; @@ -1449,7 +1450,9 @@ void conf(struct ctx *c, int argc, char **argv) fwd_default = FWD_AUTO; } - c->mtu = ROUND_DOWN(ETH_MAX_MTU - ETH_HLEN, sizeof(uint32_t)); + if (tap_l2_max_len(c) - ETH_HLEN < max_mtu) + max_mtu = tap_l2_max_len(c) - ETH_HLEN; + c->mtu = ROUND_DOWN(max_mtu, sizeof(uint32_t)); c->tcp.fwd_in.mode = c->tcp.fwd_out.mode = FWD_UNSET; c->udp.fwd_in.mode = c->udp.fwd_out.mode = FWD_UNSET; memcpy(c->our_tap_mac, MAC_OUR_LAA, ETH_ALEN); @@ -1711,9 +1714,9 @@ void conf(struct ctx *c, int argc, char **argv) if (errno || *e) die("Invalid MTU: %s", optarg); - if (mtu > ETH_MAX_MTU) { - die("MTU %lu too large (max %u)", - mtu, ETH_MAX_MTU); + if (mtu > max_mtu) { + die("MTU %lu too large (max %lu)", + mtu, max_mtu); } c->mtu = mtu; |