Replaces default "alert" logic and removed SIG_FLAG_NOALERT.
Instead, "noalert" unsets ACTION_ALERT. Same for flowbits:noalert and
friends.
In signature ordering rules w/o action are sorted as if they have 'alert',
which is the same behavior as before, but now implemented explicitly.
Ticket: #5466.
DETECT_FLOWBITS_CMD_NOALERT is misleading as it gives an impression that
noalert is a flowbit specific command that'll be used and dealt with at
some point but as soon as noalert is found in the rule lang, signature
flag for noalert is set and control is returned. It never gets added to
cmd of the flowbits object.
Ticket: #6104
And failures should be handled to say that the rule failed to load
Reverts the fix by 299ee6ed55
that was simple, but not complete (memory leak),
to have this bigger API change which simplifies code.
Implement a new design for handling var name id's. The old logic
was aware of detection engine versions and generally didn't work
well for multi-tenancy cases. Other than memory leaks and crashes,
logging of var names worked or failed based on which tenant was
loaded last.
This patch implements a new approach, where there is a global store
of vars and their id's for the lifetime of the program.
Overall Design:
Base Store: "base"
Used during keyword registration. Operates under lock. Base is shared
between all detect engines, detect engine versions and tenants.
Each variable name is ref counted.
During the freeing of a detect engine / tenant, unregistration decreases
the ref cnt.
Base has both a string to id and a id to string hash table. String to
id is used during parsing/registration. id to string during unregistration.
Active Store Pointer (atomic)
The "active" store atomic pointer points to the active lookup store. The call
to `VarNameStoreActivate` will build a new lookup store and hot swap
the pointer.
Ensuring memory safety. During the hot swap, the pointer is replaced, so
any new call to the lookup functions will automatically use the new store.
This leaves the case of any lookup happening concurrently with the pointer
swap. For this case we add the old store to a free list. It gets a timestamp
before which it cannot be freed.
Free List
The free list contains old stores that are waiting to get removed. They
contain a timestamp that is checked before they are freed.
Bug: #6044.
Bug: #6201.
Issue: 6239
This commit moves the global variables associated with engine analysis
into the detect engine context. Doing so provides encapsulation of the
analysis components as well as thread-safe operation in a multi-tenant
(context) deployment.
Multi buffer matching is implemented as a way for a rule to match
on multiple buffers within the same transaction.
Before this patch a rule like:
dns.query; content:"example"; dns.query; content:".com";
would be equivalent to:
dns.query; content:"example"; content:".com";
If a DNS query would request more than one name, e.g.:
DNS: [example.net][something.com]
Eeach would be inspected to have both patterns present. Otherwise,
it would not be a match. So the rule above would not match, as neither
example.net and somthing.com satisfy both conditions at the same time.
This patch changes this behavior. Instead of the above, each time the
sticky buffer is specified, it creates a separate detection unit. Each
buffer is a "multi buffer" sticky buffer will now be evaluated against
each "instance" of the sticky buffer.
To continue with the above example:
DNS: [example.net] <- matches 'dns.query; content:"example";'
DNS: [something.com] <- matches 'dns.query; content:".com"'
So this would now be a match.
To make sure both patterns match in a single query string, the expression
'dns.query; content:"example"; content:".com";' still works for this.
This patch doesn't yet enable the behavior for the keywords. That is
done in a follow up patch.
To be able to implement this the internal storage of parsed rules
is changed. Until this patch and array of lists was used, where the
index was the buffer id (e.g. http_uri, dns_query). Therefore there
was only one list of matches per buffer id. As a side effect this
array was always very sparsely populated as many buffers could not
be mixed.
This patch changes the internal representation. The new array is densely
packed:
dns.query; content:"1"; dns.query; bsize:1; content:"2";
[type: dns_query][list: content:"1";]
[type: dns_query][list: bsize:1; content:"2";]
The new scheme allows for multiple instances of the same buffer.
These lists are then translated into multiple inspection engines
during the final setup of the rule.
Ticket: #5784.
Work towards making `suricata-common.h` only introduce system headers
and other things that are independent of complex internal Suricata
data structures.
Update files to compile after this.
Remove special DPDK handling for strlcpy and strlcat, as this caused
many compilation failures w/o including DPDK headers for all files.
Remove packet macros from decode.h and move them into their own file,
turn them into functions and rename them to match our function naming
policy.
Some unittests used SCMalloc for allocating new Packet the unittests.
While this is valid, it leads to segmentation faults when we move to
dynamic allocation of the maximum alerts allowed to be triggered by a
single packet.
This massive patch uses PacketGetFromAlloc, which initializes a Packet
in such a way that any dynamic allocated structures within will also be
initialized.
Related to
Task #4207
This patch allows to OR multiple flowbits on isset and isnotset flowbit
actions.
e.g.
Earlier in order to check if either fb1 or fb2 was set, it was required
to write two rules,
```
alert ip any any -> any any (msg:\"Flowbit fb1 isset\"; flowbits:isset,fb1; sid:1;)
alert ip any any -> any any (msg:\"Flowbit fb2 isset\"; flowbits:isset,fb2; sid:2;)
```
now, the same can be achieved with
```
alert ip any any -> any any (msg:\"Flowbit fb2 isset\"; flowbits:isset,fb1|fb2; sid:23;)
```
This operator can be used to check if one of the many flowbits is set
and also if one of the many flowbits is not set.
The regular expression was accepting something like
"flowbits:!isset,isma;" without complaining even if it is not
correct and don't have the expected result.
When stateless rules are depending on a flowbit being set by a stateful
rule, the inspection order is almost certainly wrong.
Switch stateless rules depending on stateful rules to being stateful.
This is used to turn 'TCP stream' inspecting rules (which are stateless
unless mixed with stateful keywords) into stateful rules.
Analyze flowbits to find which bits are only checked.
Track whether they are set and checked on the same level of 'statefulness'
for later used.
Dump flowbits to json including the sids that set/check etc the bit.
Set flags by default:
-Wmissing-prototypes
-Wmissing-declarations
-Wstrict-prototypes
-Wwrite-strings
-Wcast-align
-Wbad-function-cast
-Wformat-security
-Wno-format-nonliteral
-Wmissing-format-attribute
-funsigned-char
Fix minor compiler warnings for these new flags on gcc and clang.
Until now variable names, such as flowbit names, were local to a detect
engine. This made sense as they were only ever used in that context.
For the purpose of logging these names, this needs a different approach.
The loggers live outside of the detect engine. Also, in the case of
reloads and multi-tenancy, there are even multiple detect engines, so
it would be even more tricky to access them from the outside.
This patch brings a new approach. A any time, there is a single active
hash table mapping the variable names and their id's. For multiple
tenants the table is shared between tenants.
The table is set up in a 'staging' area, where locking makes sure that
multiple loading threads don't mess things up. Then when the preparing
of a detection engine is ready, but before the detect threads are made
aware of the new detect engine, the active varname hash is swapped with
the staging instance.
For this to work, all the mappings from the 'current' or active mapping
are added to the staging table.
After the threads have reloaded and the new detection engine is active,
the old table can be freed.
For multi tenancy things are similar. The staging area is used for
setting up until the new detection engines / tenants are applied to
the system.
This patch also changes the variable 'id'/'idx' field to uint32_t. Due
to data structure padding and alignment, this should have no practical
drawback while allowing for a lot more vars.
Fixes issue: https://redmine.openinfosecfoundation.org/issues/1889
To catch the issue where the ';' is missing we have to expand the
regex to capture the whole name string, not just the leading
valid stuff. Then verify that there are no spaces in the name
(Snort has the same restriction) and fail if there is.
detect-flowbits.c: In function ‘FlowBitsTestSig02’:
detect-flowbits.c:475:4: warning: this ‘if’ clause does not guard... [-Wmisleading-indentation]
if(error_count == 5)
^~
detect-flowbits.c:478:5: note: ...this statement, but the latter is misleadingly indented as if it is guarded by the ‘if’
SigGroupBuild(de_ctx);
^~~~~~~~~~~~~
Victor Julien
Shivani Bhardwaj
Philippe Antoine
Jeff Lucovsky
Juliana Fajardini
Modupe Falodun
Philippe Antoine
Victor Julien
Antti Tönkyrä
Jeff Lucovsky
Shivani Bhardwaj
Eric Leblond
Jason Ish
maxtors