mirrors/haproxy
1
0
Fork 0
mirror of https://git.haproxy.org/git/haproxy.git/ synced 2025-08-06 15:17:01 +02:00
Code Issues Projects Releases Wiki Activity

MINOR: sample: Add converters to parse FIX messages

Browse Source 
This patch implements a couple of converters to validate and extract tag value
from a FIX (Financial Information eXchange) message. The validation consists in
a few checks such as mandatory fields and checksum computation. The extraction
can get any tag value based on a tag string or tag id.

This patch requires the istend() function. Thus it depends on "MINOR: ist: Add
istend() function to return a pointer to the end of the string".

Reviewed and Fixed by Christopher Faulet <cfaulet@haproxy.com>
This commit is contained in:
Baptiste Assmann 2020-10-22 15:39:03 +02:00 committed by Willy Tarreau
parent cf26623780
commit e138dda1e0
6 changed files with 564 additions and 1 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

2
Makefile
View File

@ -843,7 +843,7 @@ OBJS += src/mux_h2.o src/mux_fcgi.o src/http_ana.o src/stream.o \
src/ebimtree.o src/uri_auth.o src/freq_ctr.o src/ebsttree.o \
src/ebistree.o src/auth.o src/wdt.o src/http_acl.o \
src/hpack-enc.o src/hpack-huff.o src/ebtree.o src/base64.o \
src/hash.o src/dgram.o src/version.o
src/hash.o src/dgram.o src/version.o src/fix.o
ifneq ($(TRACE),)
OBJS += src/calltrace.o

46
doc/configuration.txt
View File

@ -15133,6 +15133,52 @@ field(<index>,<delimiters>[,<count>])
str(f1_f2_f3__f5),field(-2,_,3) # f2_f3_
str(f1_f2_f3__f5),field(-3,_,0) # f1_f2_f3
fix_is_valid
Parses a binary payload and performs sanity checks regarding FIX (Financial
Information eXchange):
- checks that all tag IDs and values are not empty and the tags IDs are well
numeric
- checks the BeginString tag is the first tag with a valide FIX version
- checks the BodyLength tag is the second one with the right body length
- checks the MstType tag is the third tag.
- checks that last tag in the message is the CheckSum tag with a valid
checksum
Due to current HAProxy design, only the first message sent by the client and
the server can be parsed.
This converter returns a boolean, true if the payload contains a valid FIX
message, false if not.
See also the fix_tag_value converter.
Example:
tcp-request inspect-delay 10s
tcp-request content reject unless { req.payload(0,0),fix_is_valid }
fix_tag_value(<tag>)
Parses a FIX (Financial Information eXchange) message and extracts the value
from the tag <tag>. <tag> can be a string or an integer pointing to the
desired tag. Any integer value is accepted, but only the following strings
are translated into their integer equivalent: BeginString, BodyLength,
MsgType, SenderComID, TargetComID, CheckSum. More tag names can be easily
added.
Due to current HAProxy design, only the first message sent by the client and
the server can be parsed. No message validation is performed by this
converter. It is highly recommended to validate the message first using
fix_is_valid converter.
See also the fix_is_valid converter.
Example:
tcp-request inspect-delay 10s
tcp-request content reject unless { req.payload(0,0),fix_is_valid }
# MsgType tag ID is 35, so both lines below will return the same content
tcp-request content set-var(txn.foo) req.payload(0,0),fix_tag_value(35)
tcp-request content set-var(txn.bar) req.payload(0,0),fix_tag_value(MsgType)
hex
Converts a binary input sample to a hex string containing two hex digits per
input byte. It is used to log or transfer hex dumps of some binary input data

70
include/haproxy/fix-t.h Normal file
View File

@ -0,0 +1,70 @@
/*
* include/haproxy/fix-t.h
* This file contains structure declarations for FIX protocol.
*
* Copyright 2020 Baptiste Assmann <bedis9@gmail.com>
*
* This library is free software; you can redistribute it and/or
* modify it under the terms of the GNU Lesser General Public
* License as published by the Free Software Foundation, version 2.1
* exclusively.
*
* This library is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
* Lesser General Public License for more details.
*
* You should have received a copy of the GNU Lesser General Public
* License along with this library; if not, write to the Free Software
* Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
*/
#ifndef _HAPROXY_FIX_T_H
#define _HAPROXY_FIX_T_H
#include <import/ist.h>
/*
* FIX messages are composed by a list of Tag=Value separated by a 'delimiter'
*/
#define FIX_DELIMITER 0x01
/*
* know FIX version strings
*/
#define FIX_4_0 (ist("FIX.4.0"))
#define FIX_4_1 (ist("FIX.4.1"))
#define FIX_4_2 (ist("FIX.4.2"))
#define FIX_4_3 (ist("FIX.4.3"))
#define FIX_4_4 (ist("FIX.4.4"))
#define FIX_5_0 (ist("FIXT.1.1"))
/* FIX_5_0SP1 and FIX_5_0SP2 have the same version string than FIX5_0 */
/*
* Supported FIX tag ID
*/
#define FIX_TAG_BeginString 8
#define FIX_TAG_BodyLength 9
#define FIX_TAG_CheckSum 10
#define FIX_TAG_MsgType 35
#define FIX_TAG_SenderComID 49
#define FIX_TAG_TargetComID 56
#define FIX_MSG_MINSIZE 26 /* Minimal length for a FIX Message */
#define FIX_CHKSUM_SIZE 7 /* Length of the CheckSum tag (10=NNN<delim>) */
/*
* return code when parsing / validating FIX messages
*/
#define FIX_INVALID_MESSAGE -1
#define FIX_NEED_MORE_DATA 0
#define FIX_VALID_MESSAGE 1
#endif /* _HAPROXY_FIX_T_H */
/*
* Local variables:
* c-indent-level: 8
* c-basic-offset: 8
* End:
*/

97
include/haproxy/fix.h Normal file
View File

@ -0,0 +1,97 @@
/*
* include/haproxy/fix.h
* This file contains functions and macros declarations for FIX protocol decoding.
*
* Copyright 2020 Baptiste Assmann <bedis9@gmail.com>
*
* This library is free software; you can redistribute it and/or
* modify it under the terms of the GNU Lesser General Public
* License as published by the Free Software Foundation, version 2.1
* exclusively.
*
* This library is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
* Lesser General Public License for more details.
*
* You should have received a copy of the GNU Lesser General Public
* License along with this library; if not, write to the Free Software
* Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
*/
#ifndef _HAPROXY_FIX_H
#define _HAPROXY_FIX_H
#include <import/ist.h>
#include <haproxy/fix-t.h>
#include <haproxy/tools.h>
unsigned int fix_check_id(const struct ist str, const struct ist version);
int fix_validate_message(const struct ist msg);
struct ist fix_tag_value(const struct ist msg, unsigned int tagid);
/*
* Return the FIX version string (one of FIX_X_Y macros) correspoding to
* <str> or IST_NULL if not found.
*/
static inline struct ist fix_version(const struct ist str)
{
/* 7 is the minimal size for the FIX version string */
if (istlen(str) < 7)
return IST_NULL;
if (isteq(FIX_4_0, str))
return FIX_4_0;
else if (isteq(FIX_4_1, str))
return FIX_4_1;
else if (isteq(FIX_4_2, str))
return FIX_4_2;
else if (isteq(FIX_4_3, str))
return FIX_4_3;
else if (isteq(FIX_4_4, str))
return FIX_4_4;
else if (isteq(FIX_5_0, str))
return FIX_5_0;
return IST_NULL;
}
/*
* Return the FIX tag ID corresponding to <tag> if one found or 0 if not.
*
* full list of tag ID available here, just in case we need to support
* more "string" equivalent in the future:
* https://www.onixs.biz/fix-dictionary/4.2/fields_by_tag.html
*/
static inline unsigned int fix_tagid(const struct ist tag)
{
unsigned id = fix_check_id(tag, IST_NULL);
if (id)
return id;
else if (isteqi(tag, ist("MsgType")))
return FIX_TAG_MsgType;
else if (isteqi(tag, ist("CheckSum")))
return FIX_TAG_CheckSum;
else if (isteqi(tag, ist("BodyLength")))
return FIX_TAG_BodyLength;
else if (isteqi(tag, ist("TargetComID")))
return FIX_TAG_TargetComID;
else if (isteqi(tag, ist("BeginString")))
return FIX_TAG_BeginString;
else if (isteqi(tag, ist("SenderComID")))
return FIX_TAG_SenderComID;
return 0;
}
#endif /* _HAPROXY_FIX_H */
/*
* Local variables:
* c-indent-level: 8
* c-basic-offset: 8
* End:
*/

264
src/fix.c Normal file
View File

@ -0,0 +1,264 @@
/*
* Financial Information eXchange Protocol
*
* Copyright 2020 Baptiste Assmann <bedis9@gmail.com>
*
* This program is free software; you can redistribute it and/or
* modify it under the terms of the GNU General Public License
* as published by the Free Software Foundation; either version
* 2 of the License, or (at your option) any later version.
*
*/
#include <haproxy/intops.h>
#include <haproxy/fix.h>
/*
* Return the corresponding numerical tag id if <str> looks like a valid FIX
* protocol tag ID. Otherwise, 0 is returned (0 is an invalid id).
*
* If <version> is given, it must be one of a defined FIX version string (see
* FIX_X_Y macros). In this case, the function will also check tag ID ranges. If
* no <version> is provided, any strictly positive integer is valid.
*
* tag ID range depends on FIX protocol version:
* - FIX.4.0: 1-140
* - FIX.4.1: 1-211
* - FIX.4.2: 1-446
* - FIX.4.3: 1-659
* - FIX.4.4: 1-956
* - FIX.5.0: 1-1139
* - FIX.5.0SP1: 1-1426
* - FIX.5.0SP2: 1-1621
* range 10000 to 19999 is for "user defined tags"
*/
unsigned int fix_check_id(const struct ist str, const struct ist version) {
const char *s, *end;
unsigned int ret;
s = istptr(str);
end = istend(str);
ret = read_uint(&s, end);
/* we did not consume all characters from <str>, this is an error */
if (s != end)
return 0;
/* field ID can't be 0 */
if (ret == 0)
return 0;
/* we can leave now if version was not provided */
if (!isttest(version))
return ret;
/* we can leave now if this is a "user defined tag id" */
if (ret >= 10000 && ret <= 19999)
return ret;
/* now perform checking per FIX version */
if (istissame(FIX_4_0, version) && (ret <= 140))
return ret;
else if (istissame(FIX_4_1, version) && (ret <= 211))
return ret;
else if (istissame(FIX_4_2, version) && (ret <= 446))
return ret;
else if (istissame(FIX_4_3, version) && (ret <= 659))
return ret;
else if (istissame(FIX_4_4, version) && (ret <= 956))
return ret;
/* version string is the same for all 5.0 versions, so we can only take
* into consideration the biggest range
*/
else if (istissame(FIX_5_0, version) && (ret <= 1621))
return ret;
return 0;
}
/*
* Parse a FIX message <msg> and performs following sanity checks:
*
* - checks tag ids and values are not empty
* - checks tag ids are numerical value
* - checks the first tag is BeginString with a valid version
* - checks the second tag is BodyLength with the right body length
* - checks the third tag is MsgType
* - checks the last tag is CheckSum with a valid checksum
*
* Returns:
* FIX_INVALID_MESSAGE if the message is invalid
* FIX_NEED_MORE_DATA if we need more data to fully validate the message
* FIX_VALID_MESSAGE if the message looks valid
*/
int fix_validate_message(const struct ist msg)
{
struct ist parser, version;
unsigned int tagnum, bodylen;
unsigned char checksum;
char *body;
int ret = FIX_INVALID_MESSAGE;
if (istlen(msg) < FIX_MSG_MINSIZE) {
ret = FIX_NEED_MORE_DATA;
goto end;
}
/* parsing the whole message to compute the checksum and check all tag
* ids are properly set. Here we are sure to have the 2 first tags. Thus
* the version and the body length can be checked.
*/
parser = msg;
version = IST_NULL;
checksum = tagnum = bodylen = 0;
body = NULL;
while (istlen(parser) > 0) {
struct ist tag, value;
unsigned int tagid;
const char *p, *end;
/* parse the tag ID and its value and perform first sanity checks */
value = iststop(istfind(parser, '='), FIX_DELIMITER);
/* end of value not found */
if (istend(value) == istend(parser)) {
ret = FIX_NEED_MORE_DATA;
goto end;
}
/* empty tag or empty value are forbbiden */
if (istptr(parser) == istptr(value) ||!istlen(value))
goto end;
/* value points on '='. get the tag and skip '=' */
tag = ist2(istptr(parser), istptr(value) - istptr(parser));
value = istnext(value);
/* Check the tag id */
tagid = fix_check_id(tag, version);
if (!tagid)
goto end;
tagnum++;
if (tagnum == 1) {
/* the first tag must be BeginString */
if (tagid != FIX_TAG_BeginString)
goto end;
version = fix_version(value);
if (!isttest(version))
goto end;
}
else if (tagnum == 2) {
/* the second tag must be bodyLength */
if (tagid != FIX_TAG_BodyLength)
goto end;
p = istptr(value);
end = istend(value);
bodylen = read_uint(&p, end);
/* we did not consume all characters from <str> or no body, this is an error.
* There is at least the message type in the body.
*/
if (p != end || !bodylen)
goto end;
body = istend(value) + 1;
}
else if (tagnum == 3) {
/* the third tag must be MsgType */
if (tagid != FIX_TAG_MsgType)
goto end;
}
else if (tagnum > 3 && tagid == FIX_TAG_CheckSum) {
/* CheckSum tag should be the last one and is not taken into account
* to compute the checksum itself and the body length. The value is
* a three-octet representation of the checksum decimal value.
*/
if (bodylen != istptr(parser) - body)
goto end;
if (istlen(value) != 3)
goto end;
if (checksum != strl2ui(istptr(value), istlen(value)))
goto end;
/* End of the message, exit from the loop */
ret = FIX_VALID_MESSAGE;
goto end;
}
/* compute checksum of tag=value<delim> */
for (p = istptr(tag) ; p < istend(tag) ; ++p)
checksum += *p;
checksum += '=';
for (p = istptr(value) ; p < istend(value) ; ++p)
checksum += *p;
checksum += FIX_DELIMITER;
/* move the parser after the value and its delimiter */
parser = istadv(parser, istlen(tag) + istlen(value) + 2);
}
if (body) {
/* We start to read the body but we don't reached the checksum tag */
ret = FIX_NEED_MORE_DATA;
}
end:
return ret;
}
/*
* Iter on a FIX message <msg> and return the value of <tagid>.
*
* Returns the corresponding value if <tagid> is found. If <tagid> is not found
* because more data are required, the message with a length set to 0 is
* returned. If <tagid> is not found in the message or if the message is
* invalid, IST_NULL is returned.
*
* Note: Only simple sanity checks are performed on tags and values (not empty).
*
* the tag looks like
* <tagid>=<value>FIX_DELIMITER with <tag> and <value> not empty
*/
struct ist fix_tag_value(const struct ist msg, unsigned int tagid)
{
struct ist parser, t, v;
unsigned int id;
parser = msg;
while (istlen(parser) > 0) {
v = iststop(istfind(parser, '='), FIX_DELIMITER);
/* delimiter not found, need more data */
if (istend(v) == istend(parser))
break;
/* empty tag or empty value, invalid */
if (istptr(parser) == istptr(v) || !istlen(v))
goto not_found_or_invalid;
t = ist2(istptr(parser), istptr(v) - istptr(parser));
v = istnext(v);
id = fix_check_id(t, IST_NULL);
if (!id)
goto not_found_or_invalid;
if (id == tagid) {
/* <tagId> found, return the corrsponding value */
return v;
}
/* CheckSum tag is the last one, no <tagid> found */
if (id == FIX_TAG_CheckSum)
goto not_found_or_invalid;
parser = istadv(parser, istlen(t) + istlen(v) + 2);
}
/* not enough data to find <tagid> */
return ist2(istptr(msg), 0);
not_found_or_invalid:
return IST_NULL;
}

86
src/sample.c
View File

@ -26,9 +26,11 @@
#include <haproxy/buf.h>
#include <haproxy/chunk.h>
#include <haproxy/errors.h>
#include <haproxy/fix.h>
#include <haproxy/global.h>
#include <haproxy/hash.h>
#include <haproxy/http.h>
#include <haproxy/istbuf.h>
#include <haproxy/net_helper.h>
#include <haproxy/protobuf.h>
#include <haproxy/proxy.h>
@ -3214,6 +3216,86 @@ static int sample_conv_protobuf_check(struct arg *args, struct sample_conv *conv
return 1;
}
/*
* Extract the tag value of an input binary sample. Takes a mandatory argument:
* the FIX protocol tag identifier.
* Return 1 if the tag was found, 0 if not.
*/
static int sample_conv_fix_tag_value(const struct arg *arg_p, struct sample *smp, void *private)
{
struct ist value;
smp->flags &= ~SMP_F_MAY_CHANGE;
value = fix_tag_value(ist2(smp->data.u.str.area, smp->data.u.str.data),
arg_p[0].data.sint);
if (!istlen(value)) {
if (!isttest(value)) {
/* value != IST_NULL, need more data */
smp->flags |= SMP_F_MAY_CHANGE;
}
return 0;
}
smp->data.u.str = ist2buf(value);
smp->flags |= SMP_F_CONST;
return 1;
}
/* This function checks the "fix_tag_value" converter configuration.
* It expects a "known" (by HAProxy) tag name or ID.
* Tag string names are converted to their ID counterpart because this is the
* format they are sent over the wire.
*/
static int sample_conv_fix_value_check(struct arg *args, struct sample_conv *conv,
const char *file, int line, char **err)
{
struct ist str;
unsigned int tag;
str = ist2(args[0].data.str.area, args[0].data.str.data);
tag = fix_tagid(str);
if (!tag) {
memprintf(err, "Unknown FIX tag name '%s'", args[0].data.str.area);
return 0;
}
chunk_destroy(&args[0].data.str);
args[0].type = ARGT_SINT;
args[0].data.sint = tag;
return 1;
}
/*
* Checks that a buffer contains a valid FIX message
*
* Return 1 if the check could be run, 0 if not.
* The result of the analyse itsef is stored in <smp> as a boolean
*/
static int sample_conv_fix_is_valid(const struct arg *arg_p, struct sample *smp, void *private)
{
struct ist msg;
msg = ist2(smp->data.u.str.area, smp->data.u.str.data);
smp->flags &= ~SMP_F_MAY_CHANGE;
switch (fix_validate_message(msg)) {
case FIX_VALID_MESSAGE:
smp->data.type = SMP_T_BOOL;
smp->data.u.sint = 1;
return 1;
case FIX_NEED_MORE_DATA:
smp->flags |= SMP_F_MAY_CHANGE;
return 0;
case FIX_INVALID_MESSAGE:
smp->data.type = SMP_T_BOOL;
smp->data.u.sint = 0;
return 1;
}
return 0;
}
/* This function checks the "strcmp" converter's arguments and extracts the
* variable name and its scope.
*/
@ -3802,6 +3884,10 @@ static struct sample_conv_kw_list sample_conv_kws = {ILH, {
{ "ungrpc", sample_conv_ungrpc, ARG2(1,PBUF_FNUM,STR), sample_conv_protobuf_check, SMP_T_BIN, SMP_T_BIN },
{ "protobuf", sample_conv_protobuf, ARG2(1,PBUF_FNUM,STR), sample_conv_protobuf_check, SMP_T_BIN, SMP_T_BIN },
/* FIX converters */
{ "fix_is_valid", sample_conv_fix_is_valid, 0, NULL, SMP_T_BIN, SMP_T_BOOL },
{ "fix_tag_value", sample_conv_fix_tag_value, ARG1(1,STR), sample_conv_fix_value_check, SMP_T_BIN, SMP_T_BIN },
{ "iif", sample_conv_iif, ARG2(2, STR, STR), NULL, SMP_T_BOOL, SMP_T_STR },
{ "and", sample_conv_binary_and, ARG1(1,STR), check_operator, SMP_T_SINT, SMP_T_SINT },