There is no more reason for the realign function being HTTP specific,
it only operates on a buffer now. Let's move it to buffers.c instead.
It's likely that buffer_bounce_realign is broken (not used), this will
have to be inspected. The function is worth rewriting as it can be
cheaper than buffer_slow_realign() to realign large wrapping buffers.
All keywords registered using a cfg_kw_list now make use of the new error reporting
framework. This allows easier and more precise error reporting without having to
deal with complex buffer allocation issues.
From time to time, some bugs are discovered that are caused by non-initialized
memory areas. It happens that most platforms return a zero-filled area upon
first malloc() thus hiding potential bugs. This patch also replaces malloc()
in pools with calloc() to ensure that all platforms exhibit the same behaviour
upon startup. In order to catch these bugs more easily, add a -dM command line
flag to enable memory poisonning. Optionally, passing -dM<byte> forces the
poisonning byte to <byte>.
A number of important information were missing from the error captures, so
let's improve them. Now we also log source port, session flags, transaction
flags, message flags, pending output bytes, expected buffer wrapping position,
total bytes transferred, message chunk length, and message body length.
As such, the output format has slightly evolved and the source address moved
to the third line :
[08/May/2012:11:14:36.341] frontend echo (#1): invalid request
backend echo (#1), server <NONE> (#-1), event #1
src 127.0.0.1:40616, session #4, session flags 0x00000000
HTTP msg state 26, msg flags 0x00000000, tx flags 0x00000000
HTTP chunk len 0 bytes, HTTP body len 0 bytes
buffer flags 0x00909002, out 0 bytes, total 28 bytes
pending 28 bytes, wrapping at 8030, error at position 7:
00000 GET / /?t=20000 HTTP/1.1\r\n
00026 \r\n
[08/May/2012:11:13:13.426] backend echo (#1) : invalid response
frontend echo (#1), server local (#1), event #0
src 127.0.0.1:40615, session #1, session flags 0x0000044e
HTTP msg state 32, msg flags 0x0000000e, tx flags 0x08200000
HTTP chunk len 0 bytes, HTTP body len 20 bytes
buffer flags 0x00008002, out 81 bytes, total 92 bytes
pending 11 bytes, wrapping at 7949, error at position 9:
00000 Foo: bar\r\r\n
The previous sockstream_accept() function uses nothing from sockstream, and
is totally irrelevant to stream interfaces. Move this to the protocols.c
file which handles listeners and protocols, and call it listener_accept().
It now makes much more sense that the code dealing with listen() also handles
accept() and passes it to upper layers.
These operators are used regardless of the socket protocol family. Move
them to a "sock_ops" struct. ->read and ->write have been moved there too
as they have no reason to remain at the protocol level.
Make use of the new IPv6 pattern type so that acl_match_ip() knows how to
compare pattern and sample.
IPv6 may be entered in their usual form, with or without a netmask appended.
Only bit counts are accepted for IPv6 netmasks. In order to avoid any risk of
trouble with randomly resolved IP addresses, host names are never allowed in
IPv6 patterns.
HAProxy is also able to match IPv4 addresses with IPv6 addresses in the
following situations :
- tested address is IPv4, pattern address is IPv4, the match applies
in IPv4 using the supplied mask if any.
- tested address is IPv6, pattern address is IPv6, the match applies
in IPv6 using the supplied mask if any.
- tested address is IPv6, pattern address is IPv4, the match applies in IPv4
using the pattern's mask if the IPv6 address matches with 2002:IPV4::,
::IPV4 or ::ffff:IPV4, otherwise it fails.
- tested address is IPv4, pattern address is IPv6, the IPv4 address is first
converted to IPv6 by prefixing ::ffff: in front of it, then the match is
applied in IPv6 using the supplied IPv6 mask.
We cannot currently match IPv6 addresses in ACL simply because we don't
support types on the patterns. Let's introduce this notion. For now, we
rely on the SMP_TYPES though it doesn't seem like it will last forever
given that some types are not present there (eg: regex, meth). Still it
should be enough to support mixed matchings for most types.
We use the special impossible value SMP_TYPES for types that don't exist
in the SMP_T_* space.
This is mainly a massive renaming in the code to get it in line with the
calling convention. Next patch will rename a few files to complete this
operation.
All parsing errors were known but impossible to return. Now by making use
of memprintf(), we're able to build meaningful error messages that the
caller can display.
HTTP header fetch is now done using smp_fetch_hdr() for both ACLs and
patterns. This one also supports an occurrence number, making it possible
to specify explicit occurrences for ACLs and patterns.
This way, fetch functions will be able to tell if they're called for a single
request or as part of a loop. This is important for instance when we use
hdr(foo), because in an ACL this means that all hdr(foo) occurrences must
be checked while in a pattern it means only one of them (eg: last one).
Patterns were using a bitmask to indicate if request or response was desired
in fetch functions and keywords. ACLs were using a bitmask in fetch keywords
and a single bit in fetch functions. ACLs were also using an ACL_PARTIAL bit
in fetch functions indicating that a non-final fetch was performed, which was
an abuse of the existing direction flag.
The change now consists in using :
- a capabilities field for fetch keywords => SMP_CAP_REQ/RES to indicate
if a keyword supports requests, responses, both, etc...
- an option field for fetch functions to indicate what the caller expects
(request/response, final/non-final)
The ACL_PARTIAL bit was reversed to get SMP_OPT_FINAL as it's more explicit
to know we're working on a final buffer than on a non-final one.
ACL_DIR_* were removed, as well as PATTERN_FETCH_*. L4 fetches were improved
to support being called on responses too since they're still available.
The <dir> field of all fetch functions was changed to <opt> which is now
unsigned.
The patch is large but mostly made of cosmetic changes to accomodate this, as
almost no logic change happened.
Having the args everywhere will make it easier to share fetch functions
between patterns and ACLs. The only place where we could have needed
the expr was in the http_prefetch function which can do well without.
Previously, both pattern, backend and persist_rdp_cookie would build fake
ACL expressions to fetch an RDP cookie by calling acl_fetch_rdp_cookie().
Now we switch roles. The RDP cookie fetch function is provided as a sample
fetch function that all others rely on, including ACL. The code is exactly
the same, only the args handling moved from expr->args to args. The code
was moved to proto_tcp.c, but probably that a dedicated file would be more
suited to content handling.
Now there is no more reference to union pattern_data. All pattern fetch and
conversion functions now make use of the common sample type. Note: none of
them adjust the type right now so it's important to do it next otherwise
we would risk sharing such functions with ACLs and seeing them fail.
This change is pretty minor. Struct pattern is only used for
pattern_process() now so changing it to use the common type is
quite obvious. It's worth noting that the last argument of
pattern_process() is never used so the function is self-sufficient.
Note that pattern_process() does not initialize the pattern at all
before calling fetch->process(), and that minimal initialization
will be required when we later change the argument for the sample.
These ones were either unused or improperly used. Some integers were marked
read-only, which does not make much sense. Buffers are not read-only, they're
"constant" in that they must be kept intact after any possible change.
This one is not needed anymore as we can return the data and its type in the
sample provided by the caller. ACLs now always return the proper type. BOOL
is already returned when the result is expected to be processed as a boolean.
temp_pattern has been unexported now.
The new sample types are necessary for the acl-pattern convergence.
These types are boolean and signed int. Some types were renamed for
less ambiguity (ip->ipv4, integer->uint).
The pattern type is ambiguous because a pattern is only a type and a data
part, and is normally used to match against samples. Currently, patterns
cannot hold information related to the life of the data which was extracted.
We don't want to overload patterns either, so let's add a new "sample" type
which will progressively supersede the acl_test and maybe the pattern at most
places. The sample shares similar information with patterns and also has flags
describing the data volatility and protection.
This flag was used to force a boolean match even if there was no pattern
to match. It was used only by http_auth() and designed only for this one.
It's easier and cleaner to make the fetch function perform the test and
report the boolean result as a few other functions already do. It simplifies
the acl_exec_cond() logic and will help merging ACLs and patterns.
This is used to validate that arguments are coherent. For instance,
payload_lv expects that the last arg (if any) is not more negative
than the sum of the first two. The error is reported if any.
We don't need the pattern-specific args parsers anymore, make use of the
common parser instead. We still need to improve this by adding a validation
function to report abnormal argument values or combinations. We don't report
precise parsing errors yet but this was not previously done either.
arg_i was almost unused, and since we migrated to use struct arg everywhere,
the rare cases where arg_i was needed could be replaced by switching to
arg->type = ARGT_STOP.
The types and minimal number of ACL keyword arguments are now stored in
their declaration. This will allow many more fantasies if some ACL use
several arguments or types.
Doing so required to rework all ACL keyword declarations to add two
parameters. So this was a good opportunity for a general cleanup and
to sort all entries in alphabetical order.
We still have two pending issues :
- parse_acl_expr() checks for errors but has no way to report them to
the user ;
- the types of some arguments are still not resolved and kept as strings
(eg: ARGT_FE/BE/TAB) for compatibility reasons, which must be resolved
in acl_find_targets()
The ACL parser now uses the argument parser to build a typed argument list.
Right now arguments are all strings and only one argument is supported since
this is what ACLs currently support.
make_arg_list() builds an array of typed arguments with their values,
that the caller describes how to parse. This will be used to support
multiple arguments for ACLs and patterns, which is currently problematic
and prevents ACLs and patterns from being merged. Up to 7 arguments types
may be enumerated in a single 32-bit word, including their number of
mandatory parts.
At the moment, these files are not used yet, they're only built. Note that
the 4-bit encoding for the type has left only one unused type!
This is more convenient and efficient than buf->p = b_ptr(buf, n);
It simply advances the buffer's pointer by <n> and trasfers that
amount of bytes from <in> to <out>. The BF_OUT_EMPTY flag is updated
accordingly.
A few occurrences of such computations in buffers.c and stream_sock.c
were updated to use b_adv(), which resulted in a small code shrink.
buffer_wrap_add was convenient for the migration but is not handy at all.
Let's have new wrappers that report input begin/end and output begin/end
instead.
It looks like we'll also need a b_adv(ofs) to advance a buffer's pointer.
buffer_ignore may only be used when the output of a buffer is empty,
but it's not granted it is always the case when sending HTTP error
responses. Better use buffer_cut_tail() instead, and use buffer_ignore
only on non-wrapping data.
msg->sol is now a relative pointer just like all other ones. There is no
more absolute references to the buffer outside the struct buffer itself.
Next two cleanups should include removing buffer references to functions
which already have an msg, and removal of wrapping detection in request
and response parsing which cannot wrap by definition.
ACLs and patterns only rely on a struct http_msg and don't know the pointer
to the actual data. struct http_msg will soon only hold relative references
so that's not possible. We need http_msg to hold a reference to the struct
buffer before having relative pointers everywhere.
It is likely that doing so will also result in opportunities to simplify
a number of functions arguments. The following functions are already
candidate :
http_buffer_heavy_realign
http_capture_bad_message
http_change_connection_header
http_forward_trailers
http_header_add_tail
http_header_add_tail2
http_msg_analyzer
http_parse_chunk_size
http_parse_connection_header
http_remove_header2
http_send_name_header
http_skip_chunk_crlf
http_upgrade_v09_to_v10
These offsets were relative to the buffer itself. Now they're relative to
the buffer's origin (buf->p) which normally corresponds to the start of
current message.
This saves a big dependency between the HTTP message struct and the buffers.
It appeared during this change that ->col is not used anymore (it will have
to be removed). Next step is to turn ->eol and ->sol from absolute to relative.
