mptcp: add support for ADD_ADDR "echo bit"

print "v1-echo" if the echo bit is set in the ADD_ADDR suboption (see
RFC8684 §3.4.1). While at it, dissect the 4 bits after the MPTCP option
subtype when the value is "ADD_ADDR" (0x3), according to protocol v0 and
v1. Add a selftest with a capture taken from a recent Linux kernel
implementation, and fix printout of add-addr in the existing selftests.

Signed-off-by: Davide Caratti <[email protected]>

diff --git a/print-mptcp.c b/print-mptcp.c
index cf01d9c9695f7a07d6f5c36d0325793c4cb254a2..77c26dc23ae0474992d7b6372a519e2aa5b30715 100644 (file)
--- a/print-mptcp.c
+++ b/print-mptcp.c
@@ -113,6 +113,13 @@ struct mp_dss {
 #define MP_DSS_a                        0x02
 #define MP_DSS_A                        0x01
 
+static const struct tok mptcp_addr_subecho_bits[] = {
+        { 0x6, "v0-ip6" },
+        { 0x4, "v0-ip4" },
+        { 0x1, "v1-echo" },
+        { 0x0, "v1" }
+};
+
 struct mp_add_addr {
         nd_uint8_t     kind;
         nd_uint8_t     len;
@@ -354,6 +361,9 @@ add_addr_print(netdissect_options *ndo,
             opt_len == 20 || opt_len == 22 || opt_len == 28 || opt_len == 30))
                 return 0;
 
+        ND_PRINT(" %s",
+                 tok2str(mptcp_addr_subecho_bits, "[bad version/echo]",
+                         GET_U_1(add_addr->sub_echo) & 0xF));
         ND_PRINT(" id %u", GET_U_1(add_addr->addr_id));
         if (opt_len == 8 || opt_len == 10 || opt_len == 16 || opt_len == 18) {
                 ND_PRINT(" %s", GET_IPADDR_STRING(add_addr->u.v4.addr));

diff --git a/tests/TESTLIST b/tests/TESTLIST
index 712af4f044738405e5a5103d42d67f2bec77455f..ae62f3634d4f3c04ab43526884caf0f0a3a6d8cb 100644 (file)
--- a/tests/TESTLIST
+++ b/tests/TESTLIST
@@ -229,7 +229,8 @@ msnlb2              msnlb2.pcapng           msnlb2.out
 mptcp-v0       mptcp-v0.pcap           mptcp-v0.out
 mptcp-v1       mptcp-v1.pcap           mptcp-v1.out
 mptcp-fclose   mptcp-fclose.pcap       mptcp-fclose.out
-mptcp-aa-v1     mptcp-aa-v1.pcap        mptcp-aa-v1.out
+mptcp-aa-v1    mptcp-aa-v1.pcap        mptcp-aa-v1.out
+mptcp-aa-echo  mptcp-aa-echo.pcap      mptcp-aa-echo.out
 
 # TFO tests
 tfo            tfo-5c1fa7f9ae91.pcap   tfo.out

diff --git a/tests/mptcp-aa-echo.out b/tests/mptcp-aa-echo.out
new file mode 100644 (file)
index 0000000..d44577d
--- /dev/null
+++ b/tests/mptcp-aa-echo.out
@@ -0,0 +1,2 @@
+    1  11:02:20.402400 IP 10.0.1.1.10000 > 10.0.3.2.54737: Flags [.], ack 2863732622, win 510, options [nop,nop,TS val 2041598247 ecr 805948318,mptcp add-addr v1 id 1 10.0.2.1 hmac 0xf8295862f645df19,mptcp dss ack 3502078703], length 0
+    2  11:02:20.602589 IP 10.0.1.2.35924 > 10.0.1.1.10000: Flags [.], ack 2394667731, win 501, options [nop,nop,TS val 373322532 ecr 4275366718,mptcp add-addr v1-echo id 1 10.0.2.1,mptcp dss ack 17984156407873109865], length 0

diff --git a/tests/mptcp-aa-echo.pcap b/tests/mptcp-aa-echo.pcap
new file mode 100644 (file)
index 0000000..b7d7107
Binary files /dev/null and b/tests/mptcp-aa-echo.pcap differ

diff --git a/tests/mptcp-aa-v1.out b/tests/mptcp-aa-v1.out
index 3fe5bf12d76fdf804429f10d4e2063a25168cc95..801c9ba88771969d4ae6513a3c5cc7dcbbb7bacc 100644 (file)
--- a/tests/mptcp-aa-v1.out
+++ b/tests/mptcp-aa-v1.out
@@ -10,7 +10,7 @@
    10  18:44:24.247920 IP 192.168.125.165.55555 > 192.168.125.212.52278: Flags [P.], seq 17:33, ack 17, win 509, options [nop,nop,TS val 938670368 ecr 2070300964,mptcp dss ack 17186763219675866581 seq 12148165319181844526 subseq 17 len 16,nop,nop], length 16
    11  18:44:24.248383 IP 192.168.125.212.52278 > 192.168.125.165.55555: Flags [.], ack 33, win 502, options [nop,nop,TS val 2070301169 ecr 938670368,mptcp dss ack 12148165319181844542], length 0
    12  18:44:25.046480 IP 192.168.125.212.52278 > 192.168.125.165.55555: Flags [P.], seq 17:33, ack 33, win 502, options [nop,nop,TS val 2070301967 ecr 938670368,mptcp dss ack 12148165319181844542 seq 17186763219675866581 subseq 17 len 16,nop,nop], length 16
-   13  18:44:25.046726 IP 192.168.125.165.55555 > 192.168.125.212.52278: Flags [.], ack 33, win 509, options [nop,nop,TS val 938671166 ecr 2070301967,mptcp add-addr id 1 192.168.136.225 hmac 0x669928744366716c,mptcp dss ack 17186763219675866581], length 0
+   13  18:44:25.046726 IP 192.168.125.165.55555 > 192.168.125.212.52278: Flags [.], ack 33, win 509, options [nop,nop,TS val 938671166 ecr 2070301967,mptcp add-addr v1 id 1 192.168.136.225 hmac 0x669928744366716c,mptcp dss ack 17186763219675866581], length 0
    14  18:44:25.048465 IP 192.168.125.165.55555 > 192.168.125.212.52278: Flags [P.], seq 33:49, ack 33, win 509, options [nop,nop,TS val 938671168 ecr 2070301967,mptcp dss ack 17186763219675866597 seq 12148165319181844542 subseq 33 len 16,nop,nop], length 16
    15  18:44:25.048568 IP 192.168.125.212.52278 > 192.168.125.165.55555: Flags [.], ack 49, win 502, options [nop,nop,TS val 2070301969 ecr 938671168,mptcp dss ack 12148165319181844542], length 0
    16  18:44:25.256088 IP 192.168.125.165.55555 > 192.168.125.212.52278: Flags [P.], seq 49:65, ack 33, win 509, options [nop,nop,TS val 938671376 ecr 2070301969,mptcp dss ack 17186763219675866597 seq 12148165319181844542 subseq 49 len 16,nop,nop], length 16

diff --git a/tests/mptcp-v0.out b/tests/mptcp-v0.out
index 722759d8d77f740626d5454559b82ed4a15c3d76..d3e1fa3c5f2958b0a9fae222d439e9e1813dab09 100644 (file)
--- a/tests/mptcp-v0.out
+++ b/tests/mptcp-v0.out
@@ -1,7 +1,7 @@
     1  12:56:35.701161 IP 10.2.1.2.35961 > 10.1.1.2.22: Flags [S], seq 2912457561, win 14600, options [mss 1460,sackOK,TS val 4294943152 ecr 0,nop,wscale 6,mptcp capable v0 csum {0x9c9eabd1e46a33b2}], length 0
     2  12:56:35.701661 IP 10.1.1.2.22 > 10.2.1.2.35961: Flags [S.], seq 125971326, ack 2912457562, win 14280, options [mss 1460,sackOK,TS val 4294943467 ecr 4294943152,nop,wscale 5,mptcp capable v0 csum {0x967d2770b6960552}], length 0
     3  12:56:35.702022 IP 10.2.1.2.35961 > 10.1.1.2.22: Flags [.], ack 1, win 229, options [nop,nop,TS val 4294943152 ecr 4294943467,mptcp capable v0 csum {0x9c9eabd1e46a33b2,0x967d2770b6960552}], length 0
-    4  12:56:35.786074 IP 10.1.1.2.22 > 10.2.1.2.35961: Flags [P.], seq 1:42, ack 1, win 447, options [nop,nop,TS val 4294943474 ecr 4294943152,mptcp add-addr id 1 10.1.2.2,mptcp dss ack 3576348362 seq 3518592144 subseq 1 len 41 csum 0x82f], length 41: SSH: SSH-2.0-OpenSSH_5.5p1 Debian-6+squeeze1
+    4  12:56:35.786074 IP 10.1.1.2.22 > 10.2.1.2.35961: Flags [P.], seq 1:42, ack 1, win 447, options [nop,nop,TS val 4294943474 ecr 4294943152,mptcp add-addr v0-ip4 id 1 10.1.2.2,mptcp dss ack 3576348362 seq 3518592144 subseq 1 len 41 csum 0x82f], length 41: SSH: SSH-2.0-OpenSSH_5.5p1 Debian-6+squeeze1
     5  12:56:35.786240 IP 10.2.1.2.35961 > 10.1.1.2.22: Flags [.], ack 42, win 229, options [nop,nop,TS val 4294943168 ecr 4294943474,mptcp dss ack 3518592185], length 0
     6  12:56:35.787634 IP 10.2.1.2.35961 > 10.1.1.2.22: Flags [P.], seq 1:42, ack 42, win 229, options [nop,nop,TS val 4294943168 ecr 4294943474,mptcp dss ack 3518592185 seq 3576348362 subseq 1 len 41 csum 0x45c9], length 41: SSH: SSH-2.0-OpenSSH_5.5p1 Debian-6+squeeze2
     7  12:56:35.787786 IP 10.1.1.2.22 > 10.2.1.2.35961: Flags [.], ack 42, win 447, options [nop,nop,TS val 4294943474 ecr 4294943168,mptcp dss ack 3576348403], length 0