So far, if the rule loaded had a backslash character ("\") in its
content field, the rule will fail to load but without giving a
descriptive error message. This patch tells the user to escape the
troubling character.
Before
```
9409] 7/6/2019 -- 16:12:22 - (detect-engine-loader.c:184) <Error> (DetectLoadSigFile) -- [ERRCODE: SC_ERR_INVALID_SIGNATURE(39)] - error parsing signature "alert tcp $HOME_NET any -> $EXTERNAL_NET any (msg:"Backslash needs escaping msg"; flow:established,to_server; content:"MyBackslash\here"; sid:86; rev:1; )" from file /var/lib/suricata/rules/myrule.rules at line 1
```
After
```
[9409] 7/6/2019 -- 16:12:22 - (detect-content.c:155) <Error> (DetectContentDataParse) -- [ERRCODE: SC_ERR_INVALID_SIGNATURE(39)] - '\' has to be escaped
[9409] 7/6/2019 -- 16:12:22 - (detect-engine-loader.c:184) <Error> (DetectLoadSigFile) -- [ERRCODE: SC_ERR_INVALID_SIGNATURE(39)] - error parsing signature "alert tcp $HOME_NET any -> $EXTERNAL_NET any (msg:"Backslash needs escaping msg"; flow:established,to_server; content:"MyBackslash\here"; sid:86; rev:1; )" from file /var/lib/suricata/rules/myrule.rules at line 1
```
Closes redmine ticket #2626
Stream reassembly memcap is regulated by the Init and Cleanup
callbacks. If Init fails due to memcap reached, Cleanup had no
way of knowing and it would decrease the memcap even if it hadn't
been increased by Init. This could lead to too much memory use and
memcap counter underflow.
This patch fixes the issue by not calling Cleanup in this case. It's
fair to see a failed Init the responsibility of Init.
The capture threads can receive packets from the flow manager in their
Threadvars::stream_pq packet queue. This mechanism makes sure the packets
the flow manager injects into the engine are processed by the correct
worker thread.
If the capture thread(s) would not receive packets for a long time, the
Threadvars::stream_pq would not be checked and processed. This could
lead to packet pool depletion in the flow manager. It would also lead
to flows not being timed out/logged until either packets started flowing
again or until the engine was shut down.
The scenario is more likely to happen in a test (e.g. replay) but could
also delay logging on low traffic sensors.