Till now we could only produce an HTTP/1 request from a list of H2
request headers. Now the new function h2_make_htx_request() does the
same but using the HTX encoding instead, while respecting the H2
semantics. The code is not much different from the first version,
only the encoding differs.
For now it's not used.
During startup, after the configuration parsing, all HTTP error messages
(errorloc, errorfile or default messages) are converted into HTX messages and
stored in dedicated buffers. We use it to return errors in the HTX analyzers
instead of using ugly OOB blocks.
Having a thread_local for the pool cache is messy as we need to
initialize all elements upon startup, but we can't until the threads
are created, and once created it's too late. For this reason, the
allocation code used to check for the pool's initialization, and
it was the release code which used to detect the first call and to
initialize the cache on the fly, which is not exactly optimal.
Now that we have initcalls, let's turn this into a per-thread array.
This array is initialized very early in the boot process (STG_PREPARE)
so that pools are always safe to use. This allows to remove the tests
from the alloc/free calls.
Doing just this has removed 2.5 kB of code on all cumulated pool_alloc()
and pool_free() paths.
Instead of exporting a number of pools and having to manually delete
them in deinit() or to have dedicated destructors to remove them, let's
simply kill all pools on deinit().
For this a new function pool_destroy_all() was introduced. As its name
implies, it destroys and frees all pools (provided they don't have any
user anymore of course).
This allowed to remove 4 implicit destructors, 2 explicit ones, and 11
individual calls to pool_destroy(). In addition it properly removes
the mux_pt_ctx pool which was not cleared on exit (no backport needed
here since it's 1.9 only). The sig_handler pool doesn't need to be
exported anymore and became static now.
The new function create_pool_callback() takes 3 args including the
return pointer, and creates a pool with the specified name and size.
In case of allocation error, it emits an error message and returns.
The new macro REGISTER_POOL() registers a callback using this function
and will be usable to request some pools creation and guarantee that
the allocation will be checked. An even simpler approach is to use
DECLARE_POOL() and DECLARE_STATIC_POOL() which declare and register
the pool.
Using __decl_spinlock(), __decl_rwlock(), __decl_aligned_spinlock()
and __decl_aligned_rwlock(), one can now simply declare a spinlock
or an rwlock which will automatically be initialized at boot time
by calling the ha_spin_init() or ha_rwlock_init() callback. The
"aligned" variants enforce a 64-byte alignment on the lock.
This patch adds ha_spin_init() and ha_rwlock_init() which are used as
a callback to initialise locks at boot time. They perform exactly the
same as HA_SPIN_INIT() or HA_RWLOCK_INIT() but from within a real
function.
We currently have to deal with multiple initialization stages in a way
that can be confusing, because certain parts rely on others having been
properly initialized. Most calls consist in adding lists to existing
lists, whose heads are initialized in the declaration so this is easy.
But some calls create new pools and require pools to be properly
initialized. Pools currently are thread-local and as such cannot be
pre-initialized, requiring run-time checks.
All this could be simplified by using multiple boot stages and allowing
functions to be registered at various stages.
One approach might be to use gcc's constructor priorities, but this
requires gcc >= 4.3 which eliminates a wide spectrum of working compilers,
and some versions of certain compilers (like clang 3.0) are known for
silently ignore these priorities.
Instead we can use our own init function registration mechanism. A first
attempt was made using register_function() calls in all constructors but
this made the code more painful.
This patch's approach is different. It creates sections containing
arrays of pointers to "initcall" descriptors. An initcall contains a
pointer to a function and an argument. Each section corresponds to a
specific initialization stage. Each module creates such descriptors
for various calls it requires. The main() function starts by scanning
each of these sections in turn to process these initcalls.
This will make it possible to remove many constructors from various
modules, by simply placing initcalls for the requested functions next
to the keyword lists that need to be called.
A first attempt was made by placing the initcalls directly into the
sections instead of creating an array of pointers, but it becomes
sensitive to the array's alignment which depends on the compiler and
the linker, so it seems too fragile.
For now we support 6 init stages :
- STG_PREPARE : preset variables, tables and list heads
- STG_LOCK : initialize spinlocks and rwlocks
- STG_ALLOC : allocate the required structures
- STG_POOL : create pools
- STG_REGISTER : register static lists (keywords etc)
- STG_INIT : subsystems normal initialization
These ones are declared directly in the files where they are needed
using one of the INITCALL* macros, passing 0 to 3 pointers as
arguments.
The API should possibly be extended to support a return value to give
a status to the caller, and to support a unified API, possibly a bit
more flexibility in the arguments. In this case it might make sense to
support a set of macros to register functions having a different API
and to pass the function type in the initcall itself.
Special thanks to Olivier for showing how to scan sections as this is
not something particularly well documented and exactly what I've been
missing to achieve this.
Building with musl and gcc-5.3 for MIPS returns this :
include/common/buf.h: In function 'b_dist':
include/common/buf.h:252:2: error: unknown type name 'ssize_t'
ssize_t dist = to - from;
^
Including stdint or stddef is not sufficient there to get ssize_t,
unistd is needed as well. It's likely that other platforms will have
the same issue. This patch also addresses it in ist.h and memory.h.
At the moment the situation with activity measurement is quite tricky
because the struct activity is defined in global.h and declared in
haproxy.c, with operations made in time.h and relying on freq_ctr
which are defined in freq_ctr.h which itself includes time.h. It's
barely possible to touch any of these files without breaking all the
circular dependency.
Let's move all this stuff to activity.{c,h} and be done with it. The
measurement of active and stolen time is now done in a dedicated
function called just after tv_before_poll() instead of mixing the two,
which used to be a lazy (but convenient) decision.
No code was changed, stuff was just moved around.
This was the largest function of the whole file, taking a rough second
to build alone. Let's move it to a distinct file along with a few
dependencies. Doing so saved about 2 seconds on the total build time.
The config parser is the largest file to build and its build dominates
the total project's build time. Let's start to split it into multiple
smaller pieces by extracting the "global" section parser into a new
file called "cfgparse-global.c". This removes 1/4th of the file's build
time.
These 2 functions are pretty naive. They only split a start-line into its 3
substrings or a header line into its name and value. Spaces before and after
each part are skipped. No CRLF at the end are expected.
This patch implements http_apply_early_hint_rule() function is responsible of
building HTTP 103 Early Hint responses each time a "early-hint" rule is matched.
When namespaces are disabled, support is still reported because the file
is built with almost nothing in it but built anyway. Instead of extending
the scope of the numerous ifdefs in this file, better avoid building it
when namespaces are diabled. In this case we define my_socketat() as an
inline function mapping directly to socket(). The struct netns_entry
still needs to be defined because it's used by various other functions
in the code.
It was reported here that authentication may fail when threads are
enabled :
https://bugzilla.redhat.com/show_bug.cgi?id=1643941
While I couldn't reproduce the issue, it's obvious that there is a
problem with the use of the non-reentrant crypt() function there.
On Linux systems there's crypt_r() but not on the vast majority of
other ones. Thus a first approach consists in placing a lock around
this crypt() call. Another patch may relax it when crypt_r() is
available.
This fix must be backported to 1.8. Thanks to Ryan O'Hara for the
quick notification.
Commit 27346b01a ("OPTIM: tools: optimize my_ffsl() for x86_64") optimized
my_ffsl() for intensive use cases in the scheduler, but as half of the times
I got it wrong so it counted bits the reverse way. It doesn't matter for the
scheduler nor fd cache but it broke cpu-map with threads which heavily relies
on proper ordering.
We should probably consider dropping support for gcc < 3.4 and switching
to builtins for these ones, though often they are as ambiguous.
No backport is needed.
When building with DEBUG_MEMORY_POOLS, an element returned from the
cache would not have its pool link initialized unless it's allocated
using pool_alloc(). This is problematic for buffer allocators which
use pool_alloc_dirty(), as freeing this object will make the code
think it was allocated from another pool. This patch does two things :
- make __pool_get_from_cache() set the link
- remove the extra initialization from pool_alloc() since it's always
done in either __pool_get_first() or __pool_refill_alloc()
This patch is marked MINOR since it only affects code explicitly built
for debugging. No backport is needed.
When mapping memory with mmap(), we should use a fd of -1, not 0. 0 may
work on linux, but it doesn't work on FreeBSD, and probably other OSes.
It would be nice to backport this to 1.8 to help debugging there.
Commit ac6c880 ("BUILD: memory: fix pointer declaration for atomic CAS")
attemtped to fix a build warning affecting the lock-free version of the
pool allocator. But the fix tried to hide the cause instead of addressing
it, thus clang still complains about (void **) not matching (void ***).
The real solution is to declare free_list (void **) and not to use a cast.
Now this builds fine with gcc/clang with and without threads.
No backport is needed.
The purpose is to detect if threads or processes are competing for the
same CPU. This can happen when threads are incorrectly bound, or after a
reload if the previous process still has an important activity. With
threads this situation is problematic because a preempted thread holding
a lock will block other ones waiting for this lock to be released.
A first attempt consisted in measuring the cumulated lost time more
precisely but the system's scheduler is smart enough to try to limit the
thread preemption rate by mostly context switching during poll()'s blank
periods, so most of the time lost is not seen. In essence this is good
because it means a thread is not preempted with a lock held, and even
regarding the rendez-vous point it cannot prevent the other ones from
making progress. But still it happens tens to hundreds of times per
second that a thread might be preempted, so it's still possible to detect
that the situation is happening, thus it's interesting to measure and
report its frequency.
Each time we enter the poller, we check the CPU time spent working and
see if we've lost time doing something else. To limit false positives,
we're only interested in losses of 500 microseconds or more (i.e. half
a clock tick on a 1 kHz system). If so, it indicates that some time was
stolen by another thread or process. Note that we purposely store some
sub-millisecond counters so that under heavy traffic with a 1 kHz clock,
it's still possible to measure something without being subject to the
risk of rounding errors (i.e. if exactly 1 ms is stolen it's possible
that the time difference could often be slightly lower).
This counter of lost CPU time slots time is reported in "show activity"
in numbers of milliseconds of CPU lost per second, per 15s, and total
over the process' life. By definition, the per-second counter cannot
report values larger than 1000 per thread per second and the 15s one
will be limited to 15000/s in the worst case, but it's possible that
peak values exceed such thresholds after long pauses.
These two functions retrieve respectively the monotonic clock time and
the per-thread CPU time when available on the platform, or return zero.
These syscalls may require to link with -lrt on certain libc, which is
enabled in the Makefile with USE_RT=1 (default on Linux systems).
The calls to HA_ATOMIC_CAS() on the lockfree version of the pool allocator
were mistakenly done on (void*) for the old value instead of (void **).
While this has no impact on "recent" gcc, it does have one for gcc < 4.7
since the CAS was open coded and it's not possible to assign a temporary
variable of type "void".
No backport is needed, this only affects 1.9.
By placing this code into time.h (tv_entering_poll() and tv_leaving_poll())
we can remove the logic from the pollers and prepare for extending this to
offer more accurate time measurements.
The 4 pollers all contain the same code used to compute the poll timeout.
This is pointless, let's centralize this into fd.h. This also gets rid of
the useless SCHEDULER_RESOLUTION macro which used to work arond a very old
linux 2.2 bug causing select() to wake up slightly before the timeout.
Each thread now keeps the last ~512 kB of freed objects into a local
cache. There are some heuristics involved so that a specific pool cannot
use more than 1/8 of the total cache in number of objects. Tests have
shown that 512 kB is an optimal size on a 24-thread test running on a
dual-socket machine, resulting in an overall 7.5% performance increase
and a cache miss ratio reducing from 19.2 to 17.7%. Anyway it seems
pointless to keep more than an L2 cache, which probably explains why
sizes between 256 and 512 kB are optimal.
Cached objects appear in two lists, one per pool and one LRU to help
with fair eviction. Currently there is no way to check each thread's
cache state nor to flush it. This cache cannot be disabled and is
enabled as soon as the lockless pools are enabled (i.e.: threads are
enabled, no pool debugging is in use and the CPU supports a double word
CAS).
For caching it will be convenient to have indexes associated with pools,
without having to dereference the pool itself. One solution could consist
in replacing all pool pointers with integers but this would limit the
number of allocatable pools. Instead here we allocate the 32 first pools
from a pre-allocated array whose base address is known so that it's trivial
to convert a pool to an index in this array. Pools that cannot fit there
will be allocated normally.
This statement is used as a hint for the compiler so that it knows that
the location where it's placed cannot be reached. It will mostly be used
after longjmp() or equivalent statements that deal with error processing
and that the compiler doesn't know will not return on certain conditions,
so that it doesn't complain about null dereferences on error paths.
HTTP_FLG_* and HTTP_IS_* were moved from "proto/proto_http.h" to "common/http.h"
but the associated comment was forgotten during the move.
This is 1.9-specific and should not be backported.
This call is now used quite a bit in the fd cache, to decide which cache
to add/remove the fd to/from, when waking up a task for a single thread
in __task_wakeup(), in fd_cant_recv() and in fd_process_cached_events(),
and we can replace it with a single instruction, removing ~30 instructions
and ~80 bytes from the inner loop of some of these functions.
In addition the test for zero value was replaced with a comment saying
that it is illegal and leads to an undefined behaviour. The code does
not make use of this useless case today.
In commit f161d0f51 ("BUG/MINOR: pools/threads: don't ignore DEBUG_UAF
on double-word CAS capable archs") I moved some defines and accidently
messed up with lockfree pools. The problem is that the HA_HAVE_CAS_DW
macro is not defined anymore where the CONFIG_HAP_LOCKLESS_POOLS macro
is set, so this fix implicitly disabled lockfree pools.
This patch fixes this by moving the capabilities definition to config.h
(probably that we'd benefit from having an "arch.h" file to declare the
capabilities offered by the architecture). In a test on a 12-core machine,
we used to measure 19s spent in the pool lock for 1M requests without
this patch, and 0 with it so that's definitely a net saving.
No backport is required, this is only for 1.9.
OpenSSL released support for TLSv1.3. It also added a separate function
SSL_CTX_set_ciphersuites that is used to set the ciphers used in the
TLS 1.3 handshake. This change adds support for that new configuration
option by adding a ciphersuites configuration variable that works
essentially the same as the existing ciphers setting.
Note that it should likely be backported to 1.8 in order to ease usage
of the now released openssl-1.1.1.
In ci_insert_line2() and b_rep_blk(), we can't afford to wrap, so don't use
b_tail() to check if we do, use __b_tail() instead.
This should be backported to previous versions.
The current proto_http.c file is huge and contains different processing
domains making it very difficult to work on an alternative representation.
This commit moves some parts to other files :
- ACL registration code => http_acl.c
This code only creates some ACL mappings and doesn't know anything
about HTTP nor about the representation. This code could even have
moved to acl.c but it was not worth polluting it again.
- HTTP sample conversion => http_conv.c
This code doesn't depend on the internal representation but definitely
manipulates some HTTP elements, such as dates. It also has access to
captures.
- HTTP sample fetching => http_fetch.c
This code does depend entirely on the internal representation but is
totally independent on the analysers. Placing it into a different
file will ease the transition to the new representation and the
creation of a wrapper if required. An include file was created due
to CHECK_HTTP_MESSAGE_FIRST() being used at various places.
- HTTP action registration => http_act.c
This code doesn't directly interact with the messages nor the
transaction but it does so via some exported http functions like
http_replace_req_line() or http_set_status() so it will be easier
to change only this after the conversion.
- a few very generic parts were found and moved to http.{c,h} as
relevant.
It is worth noting that the functions moved to these new files are not
referenced anywhere outside of the files and are only called as registered
callbacks, so these files do not even require associated include files.
Tim Düsterhus found using afl-fuzz that some parts of the HPACK decoder
use incorrect bounds checking which do not catch negative values after
a type cast. The first culprit is hpack_valid_idx() which takes a signed
int and is fed with an unsigned one, but a few others are affected as
well due to being designed to work with an uint16_t as in the table
header, thus not being able to detect the high offset bits, though they
are not exposed if hpack_valid_idx() is fixed.
The impact is that the HPACK decoder can be crashed by an out-of-bounds
read. The only work-around without this patch is to disable H2 in the
configuration.
CVE-2018-14645 was assigned to this bug.
This patch addresses all of these issues at once. It must be backported
to 1.8.
These two functions were apparently written on the same model as their
parents when added by commit 11bcb6c4f ("[MEDIUM] IPv6 support for syslog")
except that they perform an assignment instead of a return, and as a
result fall through the next case where the assigned value may possibly
be partially overwritten. At least under Linux the port offset is the
same in both sockaddr_in and sockaddr_in6 so the value is written twice
without side effects.
This needs to be backported as far as 1.5.
This protocol is based on the uxst one, but it uses socketpair and FD
passing insteads of a connect()/accept().
The "sockpair@" prefix has been implemented for both bind and server
keywords.
When HAProxy wants to connect through a sockpair@, it creates 2 new
sockets using the socketpair() syscall and pass one of the socket
through the FD specified on the server line.
On the bind side, haproxy will receive the FD, and will use it like it
was the FD of an accept() syscall.
This protocol was designed for internal communication within HAProxy
between the master and the workers, but it's possible to use it
externaly with a wrapper and pass the FD through environment variabls.
