Merge branch 'raimo/receive-TOS-TCLASS/ERIERL-187/OTP-15145' into maint

* raimo/receive-TOS-TCLASS/ERIERL-187/OTP-15145:
  Elaborate the disclaimer for 'pktoptions'
  Improve platform filter
  Fix endianness bug for CMSG parsing

4 files changed, 135 insertions, 56 deletions

diff --git a/erts/emulator/drivers/common/inet_drv.c b/erts/emulator/drivers/common/inet_drv.c
index 3478ba7081..7f20477363 100644
--- a/erts/emulator/drivers/common/inet_drv.c
+++ b/erts/emulator/drivers/common/inet_drv.c
@@ -634,11 +634,10 @@ static size_t my_strnlen(const char *s, size_t maxlen)
  * the pointer difference from the cmsg start pointer
  * to the CMSG_DATA(cmsg) pointer.
  */
-#define LEN_CMSG_DATA(cmsg)  ((char*)CMSG_DATA(cmsg) - (char*)(cmsg))
+#define LEN_CMSG_DATA(cmsg)                                             \
+    ((cmsg)->cmsg_len - ((char*)CMSG_DATA(cmsg) - (char*)(cmsg)))
 #define NXT_CMSG_HDR(cmsg)                                              \
-    ((struct cmsghdr*)                                                  \
-     (((char*)(cmsg)) +                                                 \
-      CMSG_SPACE((cmsg)->cmsg_len - LEN_CMSG_DATA(cmsg))))
+    ((struct cmsghdr*)(((char*)(cmsg)) + CMSG_SPACE(LEN_CMSG_DATA(cmsg))))
 #endif
 
 #if !defined(IPV6_PKTOPTIONS) && defined(IPV6_2292PKTOPTIONS)
@@ -2796,39 +2795,61 @@ static int inet_async_data(inet_descriptor* desc, const char* buf, int len)
 }
 
 #ifndef __WIN32__
+static int load_cmsg_int(ErlDrvTermData *spec, int i,
+                    struct cmsghdr *cmsg) {
+    union u {
+        byte uint8;
+        Uint16 uint16;
+        Uint32 uint32;
+        Uint64 uint64;
+    } *p;
+    p = (union u*) CMSG_DATA(cmsg);
+    switch (LEN_CMSG_DATA(cmsg) * CHAR_BIT) {
+    case 8:
+        return LOAD_INT(spec, i, p->uint8);
+    case 16:
+        return LOAD_INT(spec, i, p->uint16);
+
+    case 32:
+        return LOAD_INT(spec, i, p->uint32);
+
+    case 64:
+        return LOAD_INT(spec, i, p->uint64);
+    }
+    return LOAD_INT(spec, i, 0);
+}
+
 static int parse_ancillary_data_item(ErlDrvTermData *spec, int i,
                                      struct cmsghdr *cmsg, int *n) {
-#define LOAD_CMSG(proto, type, vtype, am, load)         \
-    if (cmsg->cmsg_level == (proto) &&                  \
-        cmsg->cmsg_type == (type)) {                    \
-        vtype *vp;                                      \
-        vp = (vtype *)CMSG_DATA(cmsg);                  \
-        i = LOAD_ATOM(spec, i, (am));                   \
-        i = load(spec, i, *vp);                         \
-        i = LOAD_TUPLE(spec, i, 2);                     \
-        (*n)++;                                         \
-        return i;                                       \
+#define LOAD_CMSG_INT(proto, type, am)              \
+    if (cmsg->cmsg_level == (proto) &&          \
+        cmsg->cmsg_type == (type)) {            \
+        i = LOAD_ATOM(spec, i, (am));           \
+        i = load_cmsg_int(spec, i, cmsg);            \
+        i = LOAD_TUPLE(spec, i, 2);             \
+        (*n)++;                                 \
+        return i;                               \
     }
 #if defined(IPPROTO_IP) && defined(IP_TOS)
-    LOAD_CMSG(IPPROTO_IP, IP_TOS, unsigned char, am_tos, LOAD_INT);
+    LOAD_CMSG_INT(IPPROTO_IP, IP_TOS, am_tos);
 #endif
 #if defined(IPPROTO_IPV6) && defined(IPV6_TCLASS)
-    LOAD_CMSG(IPPROTO_IPV6, IPV6_TCLASS, unsigned char, am_tclass, LOAD_INT);
+    LOAD_CMSG_INT(IPPROTO_IPV6, IPV6_TCLASS, am_tclass);
 #endif
 #if defined(IPPROTO_IP) && defined(IP_TTL)
-    LOAD_CMSG(IPPROTO_IP, IP_TTL, unsigned char, am_ttl, LOAD_INT);
+    LOAD_CMSG_INT(IPPROTO_IP, IP_TTL, am_ttl);
 #endif
     /* BSD uses the RECV* names in CMSG fields */
 #if defined(IPPROTO_IP) && defined(IP_RECVTOS)
-    LOAD_CMSG(IPPROTO_IP, IP_RECVTOS, unsigned char, am_tos, LOAD_INT);
+    LOAD_CMSG_INT(IPPROTO_IP, IP_RECVTOS, am_tos);
 #endif
 #if defined(IPPROTO_IPV6) && defined(IPV6_RECVTCLASS)
-    LOAD_CMSG(IPPROTO_IPV6, IPV6_RECVTCLASS, unsigned char, am_tclass, LOAD_INT);
+    LOAD_CMSG_INT(IPPROTO_IPV6, IPV6_RECVTCLASS, am_tclass);
 #endif
 #if defined(IPPROTO_IP) && defined(IP_RECVTTL)
-    LOAD_CMSG(IPPROTO_IP, IP_RECVTTL, unsigned char, am_ttl, LOAD_INT);
+    LOAD_CMSG_INT(IPPROTO_IP, IP_RECVTTL, am_ttl);
 #endif
-#undef LOAD_CMSG
+#undef LOAD_CMSG_INT
     return i;
 }
 #endif /* #ifndef __WIN32__ */
@@ -7330,6 +7351,35 @@ static int sctp_set_opts(inet_descriptor* desc, char* ptr, int len)
 }
 #endif /* HAVE_SCTP */
 
+#ifndef __WIN32__
+static void put_cmsg_int32(struct cmsghdr *cmsg, char *ptr) {
+    union u {
+        byte uint8;
+        Uint16 uint16;
+        Uint32 uint32;
+        Uint64 uint64;
+    } *p;
+    p = (union u*) CMSG_DATA(cmsg);
+    switch (LEN_CMSG_DATA(cmsg) * CHAR_BIT) {
+    case 8:
+        put_int32((Uint32) p->uint8, ptr);
+        break;
+    case 16:
+        put_int32((Uint32) p->uint16, ptr);
+        break;
+    case 32:
+        put_int32(p->uint32, ptr);
+        break;
+    case 64:
+        put_int32((Uint32) p->uint64, ptr);
+        break;
+    default:
+        put_int32(0, ptr);
+    }
+    return;
+}
+#endif
+
 /* load all option values into the buf and reply 
 ** return total length of reply filled into ptr
 ** ptr should point to a buffer with 9*len +1 to be safe!!
@@ -7796,44 +7846,37 @@ static ErlDrvSSizeT inet_fill_opts(inet_descriptor* desc,
                      cmsg = (struct cmsghdr*)cmsgbuf.buf;
                  cmsg < cmsg_top;
                  cmsg = NXT_CMSG_HDR(cmsg)) {
-#define PUT_CMSG_DATA(CMSG_LEVEL, CMSG_TYPE, OPT, TYPE, SZ, PUT)        \
-                if ((cmsg->cmsg_level == CMSG_LEVEL) &&                 \
-                    (cmsg->cmsg_type == CMSG_TYPE)) {                   \
-                    TYPE *cmsgp;                                        \
-                    cmsgp = (TYPE *)CMSG_DATA(cmsg);                    \
-                    PLACE_FOR(1+SZ, ptr);                               \
-                    *ptr = OPT;                                         \
-                    PUT(*cmsgp, ptr+1);                                 \
-                    arg_sz += 1+SZ;                                     \
-                    continue;                                           \
+#define PUT_CMSG_INT32(CMSG_LEVEL, CMSG_TYPE, OPT)      \
+                if ((cmsg->cmsg_level == CMSG_LEVEL) && \
+                    (cmsg->cmsg_type == CMSG_TYPE)) {   \
+                    PLACE_FOR(1+4, ptr);                \
+                    *ptr++ = OPT;                       \
+                    put_cmsg_int32(cmsg, ptr);          \
+                    ptr += 4;                           \
+                    arg_sz += 1+4;                      \
+                    continue;                           \
                 }
 #if defined(IPPROTO_IP) && defined(IP_TOS)
-                PUT_CMSG_DATA(IPPROTO_IP, IP_TOS,
-                              INET_OPT_TOS, unsigned char, 4, put_int32);
+                PUT_CMSG_INT32(IPPROTO_IP, IP_TOS, INET_OPT_TOS);
 #endif
 #if defined(IPPROTO_IPV6) && defined(IPV6_TCLASS)
-                PUT_CMSG_DATA(IPPROTO_IPV6, IPV6_TCLASS,
-                              INET_OPT_TCLASS, unsigned char, 4, put_int32);
+                PUT_CMSG_INT32(IPPROTO_IPV6, IPV6_TCLASS, INET_OPT_TCLASS);
 #endif
 #if defined(IPPROTO_IP) && defined(IP_TTL)
-                PUT_CMSG_DATA(IPPROTO_IP, IP_TTL,
-                              INET_OPT_TTL, unsigned char, 4, put_int32);
+                PUT_CMSG_INT32(IPPROTO_IP, IP_TTL, INET_OPT_TTL);
 #endif
                 /* BSD uses the RECV* names in CMSG fields */
             }
 #if defined(IPPROTO_IP) && defined(IP_RECVTOS)
-                PUT_CMSG_DATA(IPPROTO_IP, IP_RECVTOS,
-                              INET_OPT_TOS, unsigned char, 4, put_int32);
+                PUT_CMSG_INT32(IPPROTO_IP, IP_RECVTOS, INET_OPT_TOS);
 #endif
 #if defined(IPPROTO_IPV6) && defined(IPV6_RECVTCLASS)
-                PUT_CMSG_DATA(IPPROTO_IPV6, IPV6_RECVTCLASS,
-                              INET_OPT_TCLASS, unsigned char, 4, put_int32);
+                PUT_CMSG_INT32(IPPROTO_IPV6, IPV6_RECVTCLASS, INET_OPT_TCLASS);
 #endif
 #if defined(IPPROTO_IP) && defined(IP_RECVTTL)
-                PUT_CMSG_DATA(IPPROTO_IP, IP_RECVTTL,
-                              INET_OPT_TTL, unsigned char, 4, put_int32);
+                PUT_CMSG_INT32(IPPROTO_IP, IP_RECVTTL, INET_OPT_TTL);
 #endif
-#undef PUT_CMSG_DATA
+#undef PUT_CMSG_INT32
             put_int32(arg_sz, arg_ptr); /* Put total length */
             continue;
         }
diff --git a/lib/kernel/doc/src/gen_tcp.xml b/lib/kernel/doc/src/gen_tcp.xml
index cf649991d0..24d63693fd 100644
--- a/lib/kernel/doc/src/gen_tcp.xml
+++ b/lib/kernel/doc/src/gen_tcp.xml
@@ -74,13 +74,25 @@ do_recv(Sock, Bs) ->
       <desc>
 	<p>
 	  If the platform implements the IPv4 option
-	  <c>IP_PKTOPTIONS</c> (probably Linux specific), or the IPv6 option
+	  <c>IP_PKTOPTIONS</c>, or the IPv6 option
 	  <c>IPV6_PKTOPTIONS</c> or <c>IPV6_2292PKTOPTIONS</c> for the socket
 	  this value is returned from
 	  <seealso marker="inet#getopts/2"><c>inet:getopts/2</c></seealso>
 	  when called with the option name
 	  <seealso marker="#type-option_name"><c>pktoptions</c></seealso>.
 	</p>
+	<note>
+	  <p>
+	    This option appears to be VERY Linux specific,
+	    and its existence in future Linux kernel versions
+	    is also worrying since the option is part of RFC 2292
+	    which is since long (2003) obsoleted by RFC 3542
+	    that <em>explicitly</em> removes this possibility to get
+	    packet information from a stream socket.
+	    For comparision: it has existed in FreeBSD but is now removed,
+	    at least since FreeBSD 10.
+	  </p>
+	</note>
       </desc>
     </datatype>
     <datatype>
diff --git a/lib/kernel/test/gen_tcp_misc_SUITE.erl b/lib/kernel/test/gen_tcp_misc_SUITE.erl
index d532537eb9..358ca872f7 100644
--- a/lib/kernel/test/gen_tcp_misc_SUITE.erl
+++ b/lib/kernel/test/gen_tcp_misc_SUITE.erl
@@ -1919,7 +1919,17 @@ so_priority(Config) when is_list(Config) ->
 
 
 %% IP_RECVTOS and IP_RECVTCLASS for IP_PKTOPTIONS
-%% does not seem to be implemented in Linux until kernel 3.0
+%% does not seem to be implemented in Linux until kernel 3.1
+%%
+%% It seems pktoptions does not return valid values
+%% for IPv4 connect sockets.  On the accept socket
+%% we get valid values, but on the connect socket we get
+%% the default values for TOS and TTL.
+%%
+%% Therefore the argument CheckConnect that enables
+%% checking the returned values for the connect socket.
+%% It is only used for recvtclass that is an IPv6 option
+%% and there we get valid values from both socket ends.
 
 recvtos(_Config) ->
     test_pktoptions(
@@ -1965,25 +1975,38 @@ recvtclass(_Config) ->
 %% when machines with newer versions gets installed...
 %% If the test still fails for a plausible reason these
 %% version numbers simply should be increased.
+%% Or maybe we should change to only test on known good
+%% platforms - change {unix,_} to false?
 
-%% Using the option returns einval, so it is not implemented.
+%% pktoptions is not supported for IPv4
+recvtos_ok({unix,openbsd}, OSVer) -> not semver_lt(OSVer, {6,4,0});
 recvtos_ok({unix,darwin}, OSVer) -> not semver_lt(OSVer, {17,6,0});
+recvtos_ok({unix,freebsd}, OSVer) -> not semver_lt(OSVer, {11,2,0});
+%% Using the option returns einval, so it is not implemented.
+recvtos_ok({unix,sunos}, OSVer) -> not semver_lt(OSVer, {5,12,0});
 %% Does not return any value - not implemented for pktoptions
 recvtos_ok({unix,linux}, OSVer) -> not semver_lt(OSVer, {3,1,0});
 %%
 recvtos_ok({unix,_}, _) -> true;
 recvtos_ok(_, _) -> false.
 
+%% pktoptions is not supported for IPv4
+recvttl_ok({unix,openbsd}, OSVer) -> not semver_lt(OSVer, {6,4,0});
+recvttl_ok({unix,darwin}, OSVer) -> not semver_lt(OSVer, {17,6,0});
+recvttl_ok({unix,freebsd}, OSVer) -> not semver_lt(OSVer, {11,2,0});
+%% Using the option returns einval, so it is not implemented.
+recvttl_ok({unix,sunos}, OSVer) -> not semver_lt(OSVer, {5,12,0});
+%%
 recvttl_ok({unix,linux}, _) -> true;
 recvttl_ok({unix,_}, _) -> true;
 recvttl_ok(_, _) -> false.
 
-%% Using the option returns einval, so it is not implemented.
+%% pktoptions is not supported for IPv6
 recvtclass_ok({unix,openbsd}, OSVer) -> not semver_lt(OSVer, {6,4,0});
-recvtclass_ok({unix,freebsd}, OSVer) -> not semver_lt(OSVer, {11,2,0});
-%% Using the option returns einval up to 0.9.0, so it is not implemented.
-%% Does not return any value - not implemented for pktoptions
 recvtclass_ok({unix,darwin}, OSVer) -> not semver_lt(OSVer, {17,6,0});
+recvtclass_ok({unix,sunos}, OSVer) -> not semver_lt(OSVer, {5,12,0});
+%% Using the option returns einval, so it is not implemented.
+recvtclass_ok({unix,freebsd}, OSVer) -> not semver_lt(OSVer, {11,2,0});
 %% Does not return any value - not implemented for pktoptions
 recvtclass_ok({unix,linux}, OSVer) -> not semver_lt(OSVer, {3,1,0});
 %%
@@ -2002,18 +2025,18 @@ semver_lt({X1,Y1,Z1}, {X2,Y2,Z2}) ->
     end;
 semver_lt(_, {_,_,_}) -> false.
 
-test_pktoptions(Family, Spec, OSFilter, CheckAccept) ->
+test_pktoptions(Family, Spec, OSFilter, CheckConnect) ->
     OSType = os:type(),
     OSVer = os:version(),
     case OSFilter(OSType, OSVer) of
         true ->
             io:format("Os: ~p, ~p~n", [OSType,OSVer]),
-            test_pktoptions(Family, Spec, CheckAccept, OSType, OSVer);
+            test_pktoptions(Family, Spec, CheckConnect, OSType, OSVer);
         false ->
             {skip,{not_supported_for_os_version,{OSType,OSVer}}}
     end.
 %%
-test_pktoptions(Family, Spec, CheckAccept, OSType, OSVer) ->
+test_pktoptions(Family, Spec, CheckConnect, OSType, OSVer) ->
     Timeout = 5000,
     RecvOpts = [RecvOpt || {RecvOpt,_,_} <- Spec],
     TrueRecvOpts = [{RecvOpt,true} || {RecvOpt,_,_} <- Spec],
@@ -2105,7 +2128,7 @@ test_pktoptions(Family, Spec, CheckAccept, OSType, OSVer) ->
     ok = gen_tcp:close(S4),
     ok = gen_tcp:close(S3),
     ok = gen_tcp:close(L),
-    (Result1 and ((not CheckAccept) or (Result2 and Result3)))
+    (Result1 and ((not CheckConnect) or (Result2 and Result3)))
         orelse
         exit({failed,
               [{OptsVals1,OptsVals4,OptsVals},
diff --git a/lib/kernel/test/gen_udp_SUITE.erl b/lib/kernel/test/gen_udp_SUITE.erl
index 878e48786c..af9985de45 100644
--- a/lib/kernel/test/gen_udp_SUITE.erl
+++ b/lib/kernel/test/gen_udp_SUITE.erl
@@ -616,13 +616,14 @@ recvtclass(_Config) ->
 %% when machines with newer versions gets installed...
 %% If the test still fails for a plausible reason these
 %% version numbers simply should be increased.
+%% Or maybe we should change to only test on known good platforms?
 
 %% Using the option returns einval, so it is not implemented.
 recvtos_ok({unix,darwin}, OSVer) -> not semver_lt(OSVer, {17,6,0});
 %% Using the option returns einval, so it is not implemented.
 recvtos_ok({unix,openbsd}, OSVer) -> not semver_lt(OSVer, {6,4,0});
 %% Using the option returns einval, so it is not implemented.
-recvtos_ok({unix,sunos}, OSVer) -> not semver_lt(OSVer, {5,11,0});
+recvtos_ok({unix,sunos}, OSVer) -> not semver_lt(OSVer, {5,12,0});
 %%
 recvtos_ok({unix,_}, _) -> true;
 recvtos_ok(_, _) -> false.