[XFRM]: Define packet dropping statistics.

This statistics is shown factor dropped by transformation
at /proc/net/xfrm_stat for developer.
It is a counter designed from current transformation source code
and defined as linux private MIB.

See Documentation/networking/xfrm_proc.txt for the detail.

Signed-off-by: Masahide NAKAMURA <nakam@linux-ipv6.org>
Signed-off-by: David S. Miller <davem@davemloft.net>

1 files changed, 71 insertions, 0 deletions

diff --git a/Documentation/networking/xfrm_proc.txt b/Documentation/networking/xfrm_proc.txt
new file mode 100644
index 00000000000..ec9045b5c34
--- /dev/null
+++ b/Documentation/networking/xfrm_proc.txt
@@ -0,0 +1,71 @@
+XFRM proc - /proc/net/xfrm_* files
+==================================
+Masahide NAKAMURA <nakam@linux-ipv6.org>
+
+
+Transformation Statistics
+-------------------------
+xfrm_proc is a statistics shown factor dropped by transformation
+for developer.
+It is a counter designed from current transformation source code
+and defined like linux private MIB.
+
+Inbound statistics
+~~~~~~~~~~~~~~~~~~
+XfrmInError:
+        All errors which is not matched others
+XfrmInBufferError:
+        No buffer is left
+XfrmInHdrError:
+        Header error
+XfrmInNoStates:
+        No state is found
+        i.e. Either inbound SPI, address, or IPsec protocol at SA is wrong
+XfrmInStateProtoError:
+        Transformation protocol specific error
+        e.g. SA key is wrong
+XfrmInStateModeError:
+        Transformation mode specific error
+XfrmInSeqOutOfWindow:
+        Sequence out of window
+XfrmInStateExpired:
+        State is expired
+XfrmInStateMismatch:
+        State has mismatch option
+        e.g. UDP encapsulation type is mismatch
+XfrmInStateInvalid:
+        State is invalid
+XfrmInTmplMismatch:
+        No matching template for states
+        e.g. Inbound SAs are correct but SP rule is wrong
+XfrmInNoPols:
+        No policy is found for states
+        e.g. Inbound SAs are correct but no SP is found
+XfrmInPolBlock:
+        Policy discards
+XfrmInPolError:
+        Policy error
+
+Outbound errors
+~~~~~~~~~~~~~~~
+XfrmOutError:
+        All errors which is not matched others
+XfrmOutBundleGenError:
+        Bundle generation error
+XfrmOutBundleCheckError:
+        Bundle check error
+XfrmOutNoStates:
+        No state is found
+XfrmOutStateProtoError:
+        Transformation protocol specific error
+XfrmOutStateModeError:
+        Transformation mode specific error
+        e.g. Outer header space is not enough
+XfrmOutStateExpired:
+        State is expired
+XfrmOutPolBlock:
+        Policy discards
+XfrmOutPolDead:
+        Policy is dead
+XfrmOutPolError:
+        Policy error