doc: Rename and convert Raw socket heads-up to Markdown

Signed-off-by: Joachim Nilsson <troglobit@gmail.com>

1 files changed, 46 insertions, 0 deletions

diff --git a/doc/RAWSOCKET.md b/doc/RAWSOCKET.md
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+Raw Socket Non-Sequitur
+=======================
+by Mike D. Schiffman <mike@infonexus.com>
+
+Raw sockets are horribly non-standard across implementations.  Here is
+an incomplete list of some of the differences (corrections welcomed).
+
+Solaris, for example, has terrible support for this packet interface.
+Older OpenBSD versions and FreeBSD before 11 versions have the
+`BSD_BYTE_SWAP` issue where the `ip_len` and `ip_frag` fields must be in
+host byte order.  Linux apparently doesn't allow for the injection of
+broadcast IP datagrams.  Whenever complete control over the IP header is
+desired, use the link layer API.
+
+
+Linux 2.2+
+----------
+
+    IP fragmentation:       performed if packet is larger than MTU
+    IP checksum:            always filled in
+    IP total length:        always filled in
+    IP ID:                  filled in when zero
+    IP source address:      filled in when zero
+    IP destination address: filled in when zero
+
+    Max packet size before kernel complains: 1500 bytes
+
+
+Solaris 2.6+
+------------
+
+    IP fragmentation bits:  can't specify 
+    IP fragmentation:       performed if packet is larger than MTU
+    IP DF bit:              always set
+    IP checksum:            always filled in
+
+    Max packet size before kernel complains: ?
+
+
+OpenBSD 2.8+
+------------
+
+    IP fragmentation:       performed if packet is larger than MTU
+
+    Max packet size before kernel complains: 8192 bytes
+