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/* Copyright (C) 2007-2010 Open Information Security Foundation
*
* You can copy, redistribute or modify this Program under the terms of
* the GNU General Public License version 2 as published by the Free
* Software Foundation.
*
* This program 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 General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* version 2 along with this program; if not, write to the Free Software
* Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA
* 02110-1301, USA.
*/
/**
* \file
*
* \author Brian Rectanus <brectanu@gmail.com>
*/
#ifndef __DETECT_BYTETEST_H__
#define __DETECT_BYTETEST_H__
/** Bytetest Operators */
#define DETECT_BYTETEST_OP_LT 1 /**< "less than" operator */
#define DETECT_BYTETEST_OP_GT 2 /**< "greater than" operator */
#define DETECT_BYTETEST_OP_EQ 3 /**< "equals" operator */
#define DETECT_BYTETEST_OP_AND 4 /**< "bitwise and" operator */
#define DETECT_BYTETEST_OP_OR 5 /**< "bitwise or" operator */
#define DETECT_BYTETEST_OP_GE 6 /**< greater than equal operator */
#define DETECT_BYTETEST_OP_LE 7 /**< less than equal operator */
/** Bytetest Base */
#define DETECT_BYTETEST_BASE_UNSET 0 /**< Unset type value string (automatic)*/
#define DETECT_BYTETEST_BASE_OCT 8 /**< "oct" type value string */
#define DETECT_BYTETEST_BASE_DEC 10 /**< "dec" type value string */
#define DETECT_BYTETEST_BASE_HEX 16 /**< "hex" type value string */
/** Bytetest Flags */
#define DETECT_BYTETEST_NEGOP 0x01 /**< "!" negated operator */
#define DETECT_BYTETEST_LITTLE 0x02 /**< "little" endian value */
#define DETECT_BYTETEST_BIG 0x04 /**< "bi" endian value */
#define DETECT_BYTETEST_STRING 0x08 /**< "string" value */
#define DETECT_BYTETEST_RELATIVE 0x10 /**< "relative" offset */
#define DETECT_BYTETEST_DCE 0x20 /**< dce enabled */
#define DETECT_BYTETEST_VALUE_BE 0x40 /**< byte extract value enabled */
#define DETECT_BYTETEST_OFFSET_BE 0x80 /**< byte extract value enabled */
typedef struct DetectBytetestData_ {
uint8_t nbytes; /**< Number of bytes to compare */
uint8_t op; /**< Operator used to compare */
uint8_t base; /**< String value base (oct|dec|hex) */
uint8_t flags; /**< Flags (big|little|relative|string) */
int32_t offset; /**< Offset in payload */
uint64_t value; /**< Value to compare against */
} DetectBytetestData;
/* prototypes */
/**
* Registration function for byte_test.
*
* \todo add support for no_stream and stream_only
*/
void DetectBytetestRegister (void);
/**
* This function is used to add the parsed byte_test data
* into the current signature.
*
* \param de_ctx pointer to the Detection Engine Context
* \param s pointer to the Current Signature
* \param optstr pointer to the user provided options
*
* \retval 0 on Success
* \retval -1 on Failure
*/
int DetectBytetestSetup(DetectEngineCtx *, Signature *, char *);
/**
* \brief this function will free memory associated with DetectBytetestData
*
* \param data pointer to DetectBytetestData
*/
void DetectBytetestFree(void *ptr);
/**
* This function is used to parse byte_test options passed via
*
* byte_test: bytes, [!]op, value, offset [,flags [, ...]]
*
* flags: "big", "little", "relative", "string", "oct", "dec", "hex"
*
* \param optstr Pointer to the user provided byte_test options
* \param value Used to pass the value back, if byte_test uses a byte_extract
* var.
* \param offset Used to pass the offset back, if byte_test uses a byte_extract
* var.
*
* \retval data pointer to DetectBytetestData on success
* \retval NULL on failure
*/
DetectBytetestData *DetectBytetestParse(char *optstr, char **value,
char **offset);
/**
* This function is used to match byte_test
*
* \param t pointer to thread vars
* \param det_ctx pointer to the pattern matcher thread
* \param p pointer to the current packet
* \param m pointer to the sigmatch that we will cast into DetectBytetestData
*
* \retval -1 error
* \retval 0 no match
* \retval 1 match
*
* \todo The return seems backwards. We should return a non-zero error code. One of the error codes is "no match". As-is if someone accidentally does: if (DetectBytetestMatch(...)) { match }, then they catch an error as a match.
*/
int DetectBytetestMatch(ThreadVars *t, DetectEngineThreadCtx *det_ctx,
Packet *p, Signature *s, const SigMatchCtx *ctx);
int DetectBytetestDoMatch(DetectEngineThreadCtx *, Signature *,
const SigMatchCtx *ctx, uint8_t *, uint32_t,
uint8_t, int32_t, uint64_t);
#endif /* __DETECT_BYTETEST_H__ */
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