Extend ovpn-cli set_peer to pass the peer mssfix attribute. Use -1 as the selftest CLI sentinel for leaving mssfix unchanged, so existing timeout-only peer updates can keep omitting the netlink attribute.
Add an ovpn test stage that configures mssfix on each side of a peer pair and verifies the MSS advertised on TCP SYN packets seen on the tunnel device. This covers both TX-side and RX-side clamping, and also checks that an invalid non-zero MSS value is rejected. Signed-off-by: Ralf Lici <[email protected]> --- tools/testing/selftests/net/ovpn/ovpn-cli.c | 19 ++++- .../selftests/net/ovpn/test-close-socket.sh | 4 +- tools/testing/selftests/net/ovpn/test-mark.sh | 4 +- tools/testing/selftests/net/ovpn/test.sh | 75 +++++++++++++++++-- 4 files changed, 89 insertions(+), 13 deletions(-) diff --git a/tools/testing/selftests/net/ovpn/ovpn-cli.c b/tools/testing/selftests/net/ovpn/ovpn-cli.c index d40953375c86..ca992a7cee3d 100644 --- a/tools/testing/selftests/net/ovpn/ovpn-cli.c +++ b/tools/testing/selftests/net/ovpn/ovpn-cli.c @@ -10,6 +10,7 @@ #include <stdio.h> #include <inttypes.h> #include <stdbool.h> +#include <stdlib.h> #include <string.h> #include <errno.h> #include <unistd.h> @@ -129,6 +130,7 @@ struct ovpn_ctx { __u32 keepalive_interval; __u32 keepalive_timeout; + int mssfix; enum ovpn_key_direction key_dir; enum ovpn_key_slot key_slot; @@ -732,6 +734,8 @@ static int ovpn_set_peer(struct ovpn_ctx *ovpn) ovpn->keepalive_interval); NLA_PUT_U32(ctx->nl_msg, OVPN_A_PEER_KEEPALIVE_TIMEOUT, ovpn->keepalive_timeout); + if (ovpn->mssfix >= 0) + NLA_PUT_U16(ctx->nl_msg, OVPN_A_PEER_MSSFIX, ovpn->mssfix); nla_nest_end(ctx->nl_msg, attr); ret = ovpn_nl_msg_send(ctx, NULL); @@ -1730,13 +1734,15 @@ static void usage(const char *cmd) fprintf(stderr, "\tmark: socket FW mark value\n"); fprintf(stderr, - "* set_peer <iface> <peer_id> <keepalive_interval> <keepalive_timeout>: set peer attributes\n"); + "* set_peer <iface> <peer_id> <keepalive_interval> <keepalive_timeout> <mssfix>: set peer attributes\n"); fprintf(stderr, "\tiface: ovpn interface name\n"); fprintf(stderr, "\tpeer_id: peer ID of the peer to modify\n"); fprintf(stderr, "\tkeepalive_interval: interval for sending ping messages\n"); fprintf(stderr, "\tkeepalive_timeout: time after which a peer is timed out\n"); + fprintf(stderr, + "\tmssfix: TCP MSS value to clamp SYN packets to (0 disables, -1 leaves unchanged)\n"); fprintf(stderr, "* del_peer <iface> <peer_id>: delete peer\n"); fprintf(stderr, "\tiface: ovpn interface name\n"); @@ -2307,7 +2313,7 @@ static int ovpn_parse_cmd_args(struct ovpn_ctx *ovpn, int argc, char *argv[]) } break; case CMD_SET_PEER: - if (argc < 6) + if (argc < 7) return -EINVAL; ovpn->peer_id = strtoul(argv[3], NULL, 10); @@ -2329,6 +2335,14 @@ static int ovpn_parse_cmd_args(struct ovpn_ctx *ovpn, int argc, char *argv[]) "keepalive interval value out of range\n"); return -1; } + + errno = 0; + ovpn->mssfix = strtol(argv[6], NULL, 10); + if (errno == ERANGE || ovpn->mssfix < -1 || + ovpn->mssfix > UINT16_MAX) { + fprintf(stderr, "mssfix value out of range\n"); + return -1; + } break; case CMD_DEL_PEER: if (argc < 4) @@ -2442,6 +2456,7 @@ int main(int argc, char *argv[]) memset(&ovpn, 0, sizeof(ovpn)); ovpn.sa_family = AF_UNSPEC; ovpn.cipher = OVPN_CIPHER_ALG_NONE; + ovpn.mssfix = -1; ovpn.cmd = ovpn_parse_cmd(argv[1]); if (ovpn.cmd == CMD_INVALID) { diff --git a/tools/testing/selftests/net/ovpn/test-close-socket.sh b/tools/testing/selftests/net/ovpn/test-close-socket.sh index af1532b4d2da..091c0103bdba 100755 --- a/tools/testing/selftests/net/ovpn/test-close-socket.sh +++ b/tools/testing/selftests/net/ovpn/test-close-socket.sh @@ -41,10 +41,10 @@ ovpn_prepare_network() { peer_ns="ovpn_peer${p}" ovpn_cmd_ok "set peer0 timeout for peer ${p}" \ ip netns exec ovpn_peer0 ${OVPN_CLI} set_peer tun0 \ - ${p} 60 120 + ${p} 60 120 -1 ovpn_cmd_ok "set peer${p} timeout for peer ${p}" \ ip netns exec "${peer_ns}" ${OVPN_CLI} set_peer \ - tun${p} $((p + OVPN_ID_OFFSET)) 60 120 + tun${p} $((p + OVPN_ID_OFFSET)) 60 120 -1 done } diff --git a/tools/testing/selftests/net/ovpn/test-mark.sh b/tools/testing/selftests/net/ovpn/test-mark.sh index 5a8f47554286..11af23beea2a 100755 --- a/tools/testing/selftests/net/ovpn/test-mark.sh +++ b/tools/testing/selftests/net/ovpn/test-mark.sh @@ -54,10 +54,10 @@ ovpn_mark_prepare_network() { peer_ns="ovpn_peer${p}" ovpn_cmd_ok "set peer0 timeout for peer ${p}" \ ip netns exec ovpn_peer0 "${OVPN_CLI}" set_peer tun0 \ - "${p}" 60 120 + "${p}" 60 120 -1 ovpn_cmd_ok "set peer${p} timeout for peer ${p}" \ ip netns exec "${peer_ns}" "${OVPN_CLI}" set_peer \ - tun"${p}" $((p + OVPN_ID_OFFSET)) 60 120 + tun"${p}" $((p + OVPN_ID_OFFSET)) 60 120 -1 done } diff --git a/tools/testing/selftests/net/ovpn/test.sh b/tools/testing/selftests/net/ovpn/test.sh index c06e3135fbef..a0630034351a 100755 --- a/tools/testing/selftests/net/ovpn/test.sh +++ b/tools/testing/selftests/net/ovpn/test.sh @@ -49,10 +49,10 @@ ovpn_prepare_network() { peer_ns="ovpn_peer${p}" ovpn_cmd_ok "set peer0 timeout for peer ${p}" \ ip netns exec ovpn_peer0 ${OVPN_CLI} set_peer tun0 \ - ${p} 60 120 + ${p} 60 120 -1 ovpn_cmd_ok "set peer${p} timeout for peer ${p}" \ ip netns exec "${peer_ns}" ${OVPN_CLI} set_peer \ - tun${p} $((p + OVPN_ID_OFFSET)) 60 120 + tun${p} $((p + OVPN_ID_OFFSET)) 60 120 -1 done } @@ -142,6 +142,66 @@ ovpn_run_iperf() { wait "${iperf_pid}" || return 1 } +ovpn_run_mssfix_flow() { + local filter + local iperf_pid + local direction="$1" + local mssfix="$2" + local tcpdump_pid + + filter="tcp and src host 5.5.5.1 and dst host 5.5.5.2" + filter="${filter} and tcp[tcpflags] & tcp-syn != 0" + + ovpn_run_bg iperf_pid ip netns exec ovpn_peer1 iperf3 -1 -s + sleep 1 + + timeout 3s ip netns exec ovpn_peer1 tcpdump --immediate-mode -l -p \ + -vv -nn -i tun1 -c 1 "${filter}" 2>&1 | + grep -iq "mss ${mssfix}" & + tcpdump_pid=$! + sleep 0.3 + + ovpn_cmd_ok "run ${direction} mssfix TCP flow" \ + ip netns exec ovpn_peer0 iperf3 -t 1 -c 5.5.5.2 + + ovpn_cmd_ok "capture ${direction} mssfix TCP SYN" wait "${tcpdump_pid}" + ovpn_cmd_ok "finish ${direction} mssfix TCP server" wait "${iperf_pid}" +} + +ovpn_run_mssfix() { + local peer0_id=$((1 + OVPN_ID_OFFSET)) + + # peer0 will clamp MSS for packets exchanged with peer1 + ovpn_cmd_ok "set peer0 mssfix for peer 1" \ + ip netns exec ovpn_peer0 ${OVPN_CLI} set_peer tun0 1 \ + 60 120 900 + + ovpn_cmd_fail "reject invalid peer0 mssfix for peer 1" \ + ip netns exec ovpn_peer0 ${OVPN_CLI} set_peer tun0 1 \ + 60 120 20 + + ovpn_cmd_ok "clear peer1 mssfix for peer ${peer0_id}" \ + ip netns exec ovpn_peer1 ${OVPN_CLI} set_peer tun1 \ + "${peer0_id}" 60 120 0 + + ovpn_run_mssfix_flow "TX" 900 + + ovpn_cmd_ok "clear peer0 mssfix for peer 1" \ + ip netns exec ovpn_peer0 ${OVPN_CLI} set_peer tun0 1 \ + 60 120 0 + + # peer1 will clamp MSS for packets exchanged with peer0 + ovpn_cmd_ok "set peer1 mssfix for peer ${peer0_id}" \ + ip netns exec ovpn_peer1 ${OVPN_CLI} set_peer tun1 \ + "${peer0_id}" 60 120 901 + + ovpn_run_mssfix_flow "RX" 901 + + ovpn_cmd_ok "clear peer1 mssfix for peer ${peer0_id}" \ + ip netns exec ovpn_peer1 ${OVPN_CLI} set_peer tun1 \ + "${peer0_id}" 60 120 0 +} + ovpn_run_key_rollover() { local p local peer_ns @@ -259,11 +319,11 @@ ovpn_run_timeouts() { # Non-fatal: this may fail in some protocol modes. ovpn_cmd_mayfail "set peer0 timeout for peer ${p} (non-fatal)" \ ip netns exec ovpn_peer0 ${OVPN_CLI} set_peer tun0 \ - ${p} 3 3 + ${p} 3 3 -1 peer_ns="ovpn_peer${p}" ovpn_cmd_ok "disable timeout on peer${p} while peer0 adjusts \ state" ip netns exec "${peer_ns}" ${OVPN_CLI} set_peer \ - tun${p} $((p + OVPN_ID_OFFSET)) 0 0 + tun${p} $((p + OVPN_ID_OFFSET)) 0 0 -1 done # wait for peers to timeout sleep 5 @@ -274,7 +334,7 @@ ovpn_run_timeouts() { peer_ns="ovpn_peer${p}" ovpn_cmd_ok "set peer${p} P2P timeout" \ ip netns exec "${peer_ns}" ${OVPN_CLI} set_peer \ - tun${p} $((p + OVPN_ID_OFFSET)) 3 3 + tun${p} $((p + OVPN_ID_OFFSET)) 3 3 -1 done sleep 5 } @@ -293,9 +353,9 @@ trap ovpn_stage_err ERR ktap_print_header if [ "${OVPN_FLOAT}" == "1" ]; then - ktap_set_plan 13 + ktap_set_plan 14 else - ktap_set_plan 12 + ktap_set_plan 13 fi ovpn_cleanup @@ -307,6 +367,7 @@ ovpn_run_stage "run LAN traffic behind peer1" ovpn_run_lan_traffic [ "${OVPN_FLOAT}" == "1" ] && ovpn_run_stage "run floating peer checks" \ ovpn_run_float_mode ovpn_run_stage "run iperf throughput" ovpn_run_iperf +ovpn_run_stage "run mssfix TCP SYN clamp" ovpn_run_mssfix ovpn_run_stage "run key rollout" ovpn_run_key_rollover ovpn_run_stage "query peers" ovpn_run_queries ovpn_run_stage "query missing peer fails" ovpn_query_peer_missing -- 2.54.0 _______________________________________________ Openvpn-devel mailing list [email protected] https://lists.sourceforge.net/lists/listinfo/openvpn-devel
