Ankit Malp reported a bug that we've had since binding to devices was
implemented. Haproxy wrongly checks that the process stays privileged
after startup when a binding to a device is specified via the bind
keyword "interface". This is wrong, because after startup we're not
binding any socket anymore, and during startup if there's a permission
issue it will be immediately reported ("permission denied"). More
importantly there's no way around it as the process exits on startup
when facing such an option.
This fix should be backported to 1.7, 1.6 and 1.5.
Another minor doc issue in the use-server example, use-server refers
to server "imap", but the server below is actually called "mail".
Renames the server from "mail" to "imap".
New boolean settings have been added to disable others. Most of them have "no-" as prefix.
"enabled" disables "disabled" setting,
"no-agent-check" disables "agent-check",
"no-backup" disables "backup",
"no-check" disables "check",
"no-check-ssl" disables "check-ssl",
"no-force-sslv3" disables "force-sslv3",
"no-force-tlsv10" disables "force-tlsv10",
"no-force-tlsv11" disables "force-tlsv11",
"no-force-tlsv12" disables "force-tlsv12,
"no-send-proxy" disables "send-proxy",
"no-send-proxy-v2" disables "send-proxy-v2",
"no-send-proxy-v2-ssl" disables "send-proxy-v2-ssl",
"no-send-proxy-v2-ssl-cn" disables "send-proxy-v2-ssl-cn",
"no-ssl" disables "ssl",
"no-verifyhost" disables "verifyhost",
"sslv3" disables "no-sslv3",
"ssl-reuse" disables "no-ssl-reuse",
"stick" disables "non-stick",
"tlsv10" disables "no-tlsv10",
"tlsv11" disables "no-tlsv11",
"tlsv12" disables "no-tlsv12",
"tls-tickets" disables "no-tls-tickets".
Settings with arguments are now supported on "default-server" lines:
"addr", "ca-file", "ciphers", "crl-file", "crt", "cookie", "namespace", "observe",
"redir", "sni", "source", "tcp-ut" and "track".
From now on, all server "settings" including the new ones above are supported by
"default-server" except "id" which is only supported on "server" lines.
This patch adds 'no-agent-check' setting supported both by 'default-server'
and 'server' directives to disable an agent check for a specific server which would
have 'agent-check' set as default value (inherited from 'default-server'
'agent-check' setting), or, on 'default-server' lines, to disable 'agent-check' setting
as default value for any further 'server' declarations.
For instance, provided this configuration:
default-server agent-check
server srv1
server srv2 no-agent-check
server srv3
default-server no-agent-check
server srv4
srv1 and srv3 would have an agent check enabled contrary to srv2 and srv4.
We do not allocate anymore anything when parsing 'default-server' 'agent-check'
setting.
Before this patch, only 'server' directives could support 'disabled' setting.
This patch makes also 'default-server' directives support this setting.
It is used to disable a list of servers declared after a 'defaut-server' directive.
'enabled' new keyword has been added, both supported as 'default-server' and
'server' setting, to enable again a list of servers (so, declared after a
'default-server enabled' directive) or to explicitly enable a specific server declared
after a 'default-server disabled' directive.
For instance provided this configuration:
default-server disabled
server srv1...
server srv2...
server srv3... enabled
server srv4... enabled
srv1 and srv2 are disabled and srv3 and srv4 enabled.
This is equivalent to this configuration:
default-server disabled
server srv1...
server srv2...
default-server enabled
server srv3...
server srv4...
even if it would have been preferable/shorter to declare:
server srv3...
server srv4...
default-server disabled
server srv1...
server srv2...
as 'enabled' is the default server state.
This patch makes 'default-server' support 'addr' setting.
The code which was responsible of parsing 'server' 'addr' setting
has moved from parse_server() to implement a new parser
callable both as 'default-server' and 'server' 'addr' setting parser.
Should not break anything.
This patch makes 'default-server' directives support 'sni' settings.
A field 'sni_expr' has been added to 'struct server' to temporary
stores SNI expressions as strings during both 'default-server' and 'server'
lines parsing. So, to duplicate SNI expressions from 'default-server' 'sni' setting
for new 'server' instances we only have to "strdup" these strings as this is
often done for most of the 'server' settings.
Then, sample expressions are computed calling sample_parse_expr() (only for 'server'
instances).
A new function has been added to produce the same error output as before in case
of any error during 'sni' settings parsing (display_parser_err()).
Should not break anything.
Before this patch, only 'server' directives could support 'source' setting.
This patch makes also 'default-server' directives support this setting.
To do so, we had to extract the code responsible of parsing 'source' setting
arguments from parse_server() function and make it callable both
as 'default-server' and 'server' 'source' setting parser. So, the code is mostly
the same as before except that before allocating anything for 'struct conn_src'
members, we must free the memory previously allocated.
Should not break anything.
Before this patch, 'cookie' setting was only supported by 'server' directives.
This patch makes 'default-server' directive also support 'cookie' setting.
Should not break anything.
Before this path, 'observe' setting was only supported by 'server' directives.
This patch makes 'default-server' directives also support 'observe' setting.
Should not break anything.
Before this patch only 'server' directives could support 'redir' setting.
This patch makes also 'default-server' directives support 'redir' setting.
Should not break anything.
Before this patch only 'server' directives could support 'track' setting.
This patch makes 'default-server' directives also support this setting.
Should not break anything.
Before this patch 'check' setting was only supported by 'server' directives.
This patch makes also 'default-server' directives support this setting.
A new 'no-check' keyword parser has been implemented to disable this setting both
in 'default-server' and 'server' directives.
Should not break anything.
This patch makes 'default-server' directive support 'verifyhost' setting.
Note: there was a little memory leak when several 'verifyhost' arguments were
supplied on the same 'server' line.
This patch makes 'default-server' directive support 'send-proxy-v2-ssl'
(resp. 'send-proxy-v2-ssl-cn') setting.
A new keyword 'no-send-proxy-v2-ssl' (resp. 'no-send-proxy-v2-ssl-cn') has been
added to disable 'send-proxy-v2-ssl' (resp. 'send-proxy-v2-ssl-cn') setting both
in 'server' and 'default-server' directives.
This patch makes 'default-server' directive support 'ssl' setting.
A new keyword 'no-ssl' has been added to disable this setting both
in 'server' and 'default-server' directives.
This patch makes 'default-server' directive support 'no-sslv3' (resp. 'no-ssl-reuse',
'no-tlsv10', 'no-tlsv11', 'no-tlsv12', and 'no-tls-tickets') setting.
New keywords 'sslv3' (resp. 'ssl-reuse', 'tlsv10', 'tlsv11', 'tlsv12', and
'tls-no-tickets') have been added to disable these settings both in 'server' and
'default-server' directives.
This patch makes 'default-server' directive support 'force-sslv3'
and 'force-tlsv1[0-2]' settings.
New keywords 'no-force-sslv3' (resp. 'no-tlsv1[0-2]') have been added
to disable 'force-sslv3' (resp. 'force-tlsv1[0-2]') setting both in 'server' and
'default-server' directives.
This patch makes 'default-server' directive support 'check-ssl' setting
to enable SSL for health checks.
A new keyword 'no-check-ssl' has been added to disable this setting both in
'server' and 'default-server' directives.
This patch makes 'default-server' directive support 'send-proxy'
(resp. 'send-proxy-v2') setting.
A new keyword 'no-send-proxy' (resp. 'no-send-proxy-v2') has been added
to disable 'send-proxy' (resp. 'send-proxy-v2') setting both in 'server' and
'default-server' directives.
This patch makes 'default-server' directive support 'non-stick' setting.
A new keyword 'stick' has been added so that to disable
'non-stick' setting both in 'server' and 'default-server' directives.
This patch makes 'default-server' directive support 'check-send-proxy' setting.
A new keyword 'no-check-send-proxy' has been added so that to disable
'check-send-proxy' setting both in 'server' and 'default-server' directives.
At this time, only 'server' supported 'backup' keyword.
This patch makes also 'default-server' directive support this keyword.
A new keyword 'no-backup' has been added so that to disable 'backup' setting
both in 'server' and 'default-server' directives.
For instance, provided the following sequence of directives:
default-server backup
server srv1
server srv2 no-backup
default-server no-backup
server srv3
server srv4 backup
srv1 and srv4 are declared as backup servers,
srv2 and srv3 are declared as non-backup servers.
There is no reason to emit such an error message:
"'default-server' expects <name> and <addr>[:<port>] as arguments."
if less than two arguments are provided on 'default-server' lines.
This is a 'server' specific error message.
There is a silly case where a loop is not detected in tracked servers lists:
when a server tracks itself.
Ex:
server srv1 127.0.0.1:8000 track srv1
Well, this never happens and this does not prevent haproxy from working.
But with this next following configuration:
server srv1 127.0.0.1:8000 track srv2
server srv2 127.0.0.1:8000 track srv2
server srv3 127.0.0.1:8000 track srv2
the code in charge of detecting such loops never returns (without any error message).
haproxy becomes stuck in an infinite loop because of this statement found
in check_config_validity():
for (loop = srv->track; loop && loop != newsrv; loop = loop->track);
Again, such a configuration is never accidentally used I guess.
This latter example seems silly, but as several 'default-server' directives may be used
in the same proxy section, and as 'default-server' settings are not resetted each a
new 'default-server' line is created, it will match the following configuration, in the future,
when 'track' setting will be supported by 'default-server':
default-server track srv3
server srv1 127.0.0.1:8000
server srv2 127.0.0.1:8000
.
.
.
default-server check
server srv3 127.0.0.1:8000
(cherry picked from commit 6528fc93d3c065fdac841f24e55cfe9674a67414)
A "weakness" exist in the first implementation of the parsing of the DNS
responses: HAProxy always choses the first IP available matching family
preference, or as a failover, the first IP.
It should be good enough, since most DNS servers do round robin on the
records they send back to clients.
That said, some servers does not do proper round robin, or we may be
unlucky too and deliver the same IP to all the servers sharing the same
hostname.
Let's take the simple configuration below:
backend bk
srv s1 www:80 check resolvers R
srv s2 www:80 check resolvers R
The DNS server configured with 2 IPs for 'www'.
If you're unlucky, then HAProxy may apply the same IP to both servers.
Current patch improves this situation by weighting the decision
algorithm to ensure we'll prefer use first an IP found in the response
which is not already affected to any server.
The new algorithm does not guarantee that the chosen IP is healthy,
neither a fair distribution of IPs amongst the servers in the farm,
etc...
It only guarantees that if the DNS server returns many records for a
hostname and that this hostname is being resolved by multiple servers in
the same backend, then we'll use as many records as possible.
If a server fails, HAProxy won't pick up an other record from the
response.
When SIGUSR1 is received, haproxy enters in soft-stop and quits when no
connection remains.
It can happen that the instance remains alive for a long time, depending
on timeouts and traffic. This option ensures that soft-stop won't run
for too long.
Example:
global
hard-stop-after 30s # Once in soft-stop, the instance will remain
# alive for at most 30 seconds.
Add SSL-related TLV types PP2_SUBTYPE_SSL_CIPHER,
PP2_SUBTYPE_SSL_SIG_ALG and PP2_SUBTYPE_SSL_KEY_ALG. Rename
PP2_TYPE_CHECKSUM to PP2_TYPE_CRC32C to make it easier to add checksums
using other algorithms. Clarified encoding of the string fields.
Renamed ASCII to US-ASCII as recommended by
https://www.iana.org/assignments/character-sets/character-sets.xhtml.
Add the CRC32c checksum TLV PP2_TYPE_CHECKSUM. Reserve TLV type ranges
CUSTOM, EXPERIMENT and FUTURE. Clarify that only UNSPEC protocol byte is
mandatory to implement on the receiver.
kevent() always sets EV_EOF with EVFILT_READ to notify of a read shutdown
and EV_EOF with EVFILT_WRITE to notify of a write error. Let's check this
flag to properly update the FD's polled status (FD_POLL_HUP and FD_POLL_ERR
respectively).
It's worth noting that this one can be coupled with a regular read event
to notify about a pending read followed by a shutdown, but for now we only
use this to set the relevant flags (HUP and ERR).
The poller now exhibits the flag HAP_POLL_F_RDHUP to indicate this new
capability.
An improvement may consist in not setting FD_POLL_IN when the "data"
field is null since it normally only reflects the amount of pending
data.
After commit e852545 ("MEDIUM: polling: centralize polled events processing")
all pollers stopped to explicitly check the FD's polled status, except the
kqueue poller which is constructed a bit differently. It doesn't seem possible
to cause any issue such as missing an event however, but anyway it's better to
definitely get rid of this since the event filter already provides the event
direction.
On Linux since 2.6.17 poll() supports POLLRDHUP to notify of an upcoming
hangup after pending data. Making use of it allows us to avoid a useless
recv() after short responses on keep-alive connections. Note that we
automatically enable the feature once this flag has been met first in a
poll() status. Till now it was only enabled on epoll.
Curu Wong reported a case where haproxy used to send RST to a server
after receiving its FIN. The problem is caused by the fact that being
a server connection, its fd is marked with linger_risk=1, and that the
poller didn't report POLLRDHUP, making haproxy unaware of a pending
shutdown that came after the data, so it used to resort to nolinger
for closing.
However when pollers support RDHUP we're pretty certain whether or not
a shutdown comes after the data and we don't need to perform that extra
recv() call.
Similarly when we're dealing with an inbound connection we don't care
and don't want to perform this extra recv after a request for a very
unlikely case, as in any case we'll have to deal with the client-facing
TIME_WAIT socket.
So this patch ensures that only when it's known that there's no risk with
lingering data, as well as in cases where it's known that the poller would
have detected a pending RDHUP, we perform the fd_done_recv() otherwise we
continue, trying a subsequent recv() to try to detect a pending shutdown.
This effectively results in an extra recv() call for keep-alive sockets
connected to a server when POLLRDHUP isn't known to be supported, but
it's the only way to know whether they're still alive or closed.
This fix should be backported to 1.7, 1.6 and 1.5. It relies on the
previous patch bringing support for the HAP_POLL_F_RDHUP flag.
We'll need to differenciate between pollers which can report hangup at
the same time as read (POLL_RDHUP) from the other ones, because only
these ones may benefit from the fd_done_recv() optimization. Epoll has
had support for EPOLLRDHUP since Linux 2.6.17 and has always been used
this way in haproxy, so now we only set the flag once we've observed it
once in a response. It means that some initial requests may try to
perform a second recv() call, but after the first closed connection it
will be enough to know that the second call is not needed anymore.
Later we may extend these flags to designate event-triggered pollers.
A tcp half connection can cause 100% CPU on expiration.
First reproduced with this haproxy configuration :
global
tune.bufsize 10485760
defaults
timeout server-fin 90s
timeout client-fin 90s
backend node2
mode tcp
timeout server 900s
timeout connect 10s
server def 127.0.0.1:3333
frontend fe_api
mode tcp
timeout client 900s
bind :1990
use_backend node2
Ie timeout server-fin shorter than timeout server, the backend server
sends data, this package is left in the cache of haproxy, the backend
server continue sending fin package, haproxy recv fin package. this
time the session information is as follows:
time the session information is as follows:
0x2373470: proto=tcpv4 src=127.0.0.1:39513 fe=fe_api be=node2
srv=def ts=08 age=1s calls=3 rq[f=848000h,i=0,an=00h,rx=14m58s,wx=,ax=]
rp[f=8004c020h,i=0,an=00h,rx=,wx=14m58s,ax=] s0=[7,0h,fd=6,ex=]
s1=[7,18h,fd=7,ex=] exp=14m58s
rp has set the CF_SHUTR state, next, the client sends the fin package,
session information is as follows:
0x2373470: proto=tcpv4 src=127.0.0.1:39513 fe=fe_api be=node2
srv=def ts=08 age=38s calls=4 rq[f=84a020h,i=0,an=00h,rx=,wx=,ax=]
rp[f=8004c020h,i=0,an=00h,rx=1m11s,wx=14m21s,ax=] s0=[7,0h,fd=6,ex=]
s1=[9,10h,fd=7,ex=] exp=1m11s
After waiting 90s, session information is as follows:
0x2373470: proto=tcpv4 src=127.0.0.1:39513 fe=fe_api be=node2
srv=def ts=04 age=4m11s calls=718074391 rq[f=84a020h,i=0,an=00h,rx=,wx=,ax=]
rp[f=8004c020h,i=0,an=00h,rx=?,wx=10m49s,ax=] s0=[7,0h,fd=6,ex=]
s1=[9,10h,fd=7,ex=] exp=? run(nice=0)
cpu information:
6899 root 20 0 112224 21408 4260 R 100.0 0.7 3:04.96 haproxy
Buffering is set to ensure that there is data in the haproxy buffer, and haproxy
can receive the fin package, set the CF_SHUTR flag, If the CF_SHUTR flag has been
set, The following code does not clear the timeout message, causing cpu 100%:
stream.c:process_stream:
if (unlikely((res->flags & (CF_SHUTR|CF_READ_TIMEOUT)) == CF_READ_TIMEOUT)) {
if (si_b->flags & SI_FL_NOHALF)
si_b->flags |= SI_FL_NOLINGER;
si_shutr(si_b);
}
If you have closed the read, set the read timeout does not make sense.
With or without cf_shutr, read timeout is set:
if (tick_isset(s->be->timeout.serverfin)) {
res->rto = s->be->timeout.serverfin;
res->rex = tick_add(now_ms, res->rto);
}
After discussion on the mailing list, setting half-closed timeouts the
hard way here doesn't make sense. They should be set only at the moment
the shutdown() is performed. It will also solve a special case which was
already reported of some half-closed timeouts not working when the shutw()
is performed directly at the stream-interface layer (no analyser involved).
Since the stream interface layer cannot know the timeout values, we'll have
to store them directly in the stream interface so that they are used upon
shutw(). This patch does this, fixing the problem.
An easier reproducer to validate the fix is to keep the huge buffer and
shorten all timeouts, then call it under tcploop server and client, and
wait 3 seconds to see haproxy run at 100% CPU :
global
tune.bufsize 10485760
listen px
bind :1990
timeout client 90s
timeout server 90s
timeout connect 1s
timeout server-fin 3s
timeout client-fin 3s
server def 127.0.0.1:3333
$ tcploop 3333 L W N20 A P100 F P10000 &
$ tcploop 127.0.0.1:1990 C S10000000 F
Guillaume Michaud reported against Cyril's haproxy-dconv project
that the index for the Examples section should be 2.5 instead of
2.4.
Should be backported to 1.7 and 1.6, so that the example section
can be linked to:
https://cbonte.github.io/haproxy-dconv/1.6/configuration.html#2.5
Because of this typo, AN_RES_FLT_END was never called when a redirect rule is
applied on a keep-alive connection. In almost all cases, this bug has no
effect. But, it leads to a memory leak if a redirect is done on a http-response
rule when the HTTP compression is enabled.
This patch should be backported in 1.7.