exceptions.h File Reference

#include "except.h"
#include <wsutil/ws_assert.h>

Go to the source code of this file.

Macros
#define	XCEPT_GROUP_WIRESHARK   1
#define	BoundsError   1
#define	ContainedBoundsError   2
#define	ReportedBoundsError   3
#define	FragmentBoundsError   4
#define	TypeError   5
#define	DissectorError   6
#define	ScsiBoundsError   7
#define	OutOfMemoryError   8
#define	ReassemblyError   9
#define	CATCH_NONFATAL_ERRORS    CATCH4(ReportedBoundsError, ContainedBoundsError, ScsiBoundsError, ReassemblyError)
#define	CATCH_BOUNDS_ERRORS
#define	CATCH_BOUNDS_AND_DISSECTOR_ERRORS
#define	EXCEPT_CAUGHT
#define	EXCEPT_RETHROWN
#define	EXCEPT_FINALLY
#define	TRY
#define	ENDTRY
#define	CATCH(x)
#define	CATCH2(x, y)
#define	CATCH3(x, y, z)
#define	CATCH4(w, x, y, z)
#define	CATCH5(v, w, x, y, z)
#define	CATCH6(u, v, w, x, y, z)
#define	CATCH7(t, u, v, w, x, y, z)
#define	CATCH_ALL
#define	FINALLY
#define	THROW(x)    except_throw(XCEPT_GROUP_WIRESHARK, (x), NULL)
#define	THROW_ON(cond, x)
#define	THROW_MESSAGE(x, y)    except_throw(XCEPT_GROUP_WIRESHARK, (x), (y))
#define	THROW_MESSAGE_ON(cond, x, y)
#define	THROW_FORMATTED(x, ...)    except_throwf(XCEPT_GROUP_WIRESHARK, (x), __VA_ARGS__)
#define	VTHROW_FORMATTED(x, format, args)    except_vthrowf(XCEPT_GROUP_WIRESHARK, (x), format, args)
#define	GET_MESSAGE   except_message(exc)
#define	RETHROW
#define	EXCEPT_CODE   except_code(exc)
#define	CLEANUP_PUSH(f, a)   except_cleanup_push((f),(a))
#define	CLEANUP_POP   except_cleanup_pop(0)
#define	CLEANUP_CALL_AND_POP   except_cleanup_pop(1)
#define	CLEANUP_PUSH_PFX(pfx, f, a)   except_cleanup_push_pfx(pfx,(f),(a))
#define	CLEANUP_POP_PFX(pfx)   except_cleanup_pop_pfx(pfx,0)
#define	CLEANUP_CALL_AND_POP_PFX(pfx)   except_cleanup_pop_pfx(pfx,1)

Detailed Description

Wireshark's exceptions.

Wireshark - Network traffic analyzer By Gerald Combs geral.nosp@m.d@wi.nosp@m.resha.nosp@m.rk.o.nosp@m.rg Copyright 1998 Gerald Combs

SPDX-License-Identifier: GPL-2.0-or-later

Macro Definition Documentation

BoundsError

#define BoundsError   1

Index is beyond the captured length of the tvbuff. This generally means that the capture was done with a "slice" length or "snapshot" length less than the maximum packet size, and a link-layer packet was cut short by that, so not all of the data in the link-layer packet was available.

CATCH

#define CATCH

(

x

)

Value:

    if (except_state == 0 && exc != 0 && \
        exc->except_id.except_code == (x) && \
        (except_state |= EXCEPT_CAUGHT)) \
        /* user's code goes here */

CATCH2

#define CATCH2	(		x,
			y
	)

Value:

    if (except_state == 0 && exc != 0 && \
        (exc->except_id.except_code == (x) || \
         exc->except_id.except_code == (y)) && \
        (except_state|=EXCEPT_CAUGHT)) \
        /* user's code goes here */

CATCH3

#define CATCH3	(		x,
			y,
			z
	)

Value:

    if (except_state == 0 && exc != 0 && \
        (exc->except_id.except_code == (x) || \
         exc->except_id.except_code == (y) || \
         exc->except_id.except_code == (z)) && \
        (except_state|=EXCEPT_CAUGHT)) \
        /* user's code goes here */

CATCH4

#define CATCH4	(		w,
			x,
			y,
			z
	)

Value:

    if (except_state == 0 && exc != 0 && \
        (exc->except_id.except_code == (w) || \
         exc->except_id.except_code == (x) || \
         exc->except_id.except_code == (y) || \
         exc->except_id.except_code == (z)) && \
        (except_state|=EXCEPT_CAUGHT)) \
        /* user's code goes here */

CATCH5

#define CATCH5	(		v,
			w,
			x,
			y,
			z
	)

Value:

    if (except_state == 0 && exc != 0 && \
        (exc->except_id.except_code == (v) || \
         exc->except_id.except_code == (w) || \
         exc->except_id.except_code == (x) || \
         exc->except_id.except_code == (y) || \
         exc->except_id.except_code == (z)) && \
        (except_state|=EXCEPT_CAUGHT)) \
        /* user's code goes here */

CATCH6

#define CATCH6	(		u,
			v,
			w,
			x,
			y,
			z
	)

Value:

    if (except_state == 0 && exc != 0 && \
        (exc->except_id.except_code == (u) || \
         exc->except_id.except_code == (v) || \
         exc->except_id.except_code == (w) || \
         exc->except_id.except_code == (x) || \
         exc->except_id.except_code == (y) || \
         exc->except_id.except_code == (z)) && \
        (except_state|=EXCEPT_CAUGHT)) \
        /* user's code goes here */

CATCH7

#define CATCH7	(		t,
			u,
			v,
			w,
			x,
			y,
			z
	)

Value:

    if (except_state == 0 && exc != 0 && \
        (exc->except_id.except_code == (t) || \
         exc->except_id.except_code == (u) || \
         exc->except_id.except_code == (v) || \
         exc->except_id.except_code == (w) || \
         exc->except_id.except_code == (x) || \
         exc->except_id.except_code == (y) || \
         exc->except_id.except_code == (z)) && \
        (except_state|=EXCEPT_CAUGHT)) \
        /* user's code goes here */

CATCH_ALL

#define CATCH_ALL

Value:

    if (except_state == 0 && exc != 0 && \
        (except_state|=EXCEPT_CAUGHT)) \
        /* user's code goes here */

CATCH_BOUNDS_AND_DISSECTOR_ERRORS

#define CATCH_BOUNDS_AND_DISSECTOR_ERRORS

Value:

    CATCH7(BoundsError, FragmentBoundsError, ContainedBoundsError, \
           ReportedBoundsError, ScsiBoundsError, DissectorError, \
           ReassemblyError)

CATCH_BOUNDS_ERRORS

#define CATCH_BOUNDS_ERRORS

Value:

    CATCH5(BoundsError, FragmentBoundsError, ReportedBoundsError, \
           ContainedBoundsError, ScsiBoundsError)

ContainedBoundsError

#define ContainedBoundsError   2

Index is beyond the contained length of the tvbuff. This generally means that the tvbuff was constructed as a subset of a parent tvbuff, based on a length specified by data in the packet, but the length in question runs past the reported length of the data in the parent tvbuff. That means that the packet is invalid, as the data indicating the length says the length exceeds what's contained in the packet. It is therefore currently reported as a "Malformed packet".

DissectorError

#define DissectorError   6

A bug was detected in a dissector.

DO NOT throw this with THROW(); that means that no details about the dissector error will be reported. (Instead, the message will blame you for not providing details.)

Instead, use the DISSECTOR_ASSERT(), etc. macros in epan/proto.h.

ENDTRY

#define ENDTRY

Value:

    /* rethrow the exception if necessary */ \
    if(!(except_state&EXCEPT_CAUGHT) && exc != 0)  \
        except_rethrow(exc);                 \
    except_try_pop();\
}

EXCEPT_CAUGHT

#define EXCEPT_CAUGHT

Value:

                           1 /* exception has been caught, no need to rethrow at
                           * ENDTRY */

EXCEPT_FINALLY

#define EXCEPT_FINALLY

Value:

                           4 /* we've entered the FINALLY block - don't allow
                           * RETHROW, and don't reenter FINALLY if a
                           * different exception is thrown */

EXCEPT_RETHROWN

#define EXCEPT_RETHROWN

Value:

                           2 /* the exception was rethrown from a CATCH
                           * block. Don't reenter the CATCH blocks, but do
                           * execute FINALLY and rethrow at ENDTRY */

FINALLY

#define FINALLY

Value:

    if( !(except_state & EXCEPT_FINALLY) && (except_state|=EXCEPT_FINALLY)) \
        /* user's code goes here */

FragmentBoundsError

#define FragmentBoundsError   4

Index is beyond the contained length, and possibly the reported length, of the tvbuff, but we believe it is an unreassembled fragment, either because the "this is an unreassembled fragment" flag or pinfo->fragmented is set. This means that the packet wasn't reassembled, but could possibly be correctly dissected if reassembly preferences were changed. It is therefore not reported as a "Malformed packet".

OutOfMemoryError

#define OutOfMemoryError   8

Running out of memory. A dissector tried to allocate memory but that failed.

ReassemblyError

#define ReassemblyError   9

The reassembly state machine was passed a bad fragment offset, or other similar issues. We used to use DissectorError in these cases, but they're not necessarily the dissector's fault - if the packet contains a bad fragment offset, the dissector shouldn't have to figure that out by itself since that's what the reassembly machine is for.

ReportedBoundsError

#define ReportedBoundsError   3

Index is beyond the reported length of the tvbuff. This generally means that the packet is invalid, i.e. whatever code constructed the packet and put it on the wire didn't put enough data into it. It is therefore currently reported as a "Malformed packet".

RETHROW

#define RETHROW

Value:

{                                                   \
    /* check we're in a catch block */          \
    ws_assert(except_state == EXCEPT_CAUGHT);    \
    /* we can't use except_rethrow here, as that pops a catch block \
     * off the stack, and we don't want to do that, because we want to \
     * execute the FINALLY {} block first.     \
     * except_throw doesn't provide an interface to rethrow an existing \
     * exception; however, longjmping back to except_try_push() has the \
     * desired effect.              \
     *                      \
     * Note also that THROW and RETHROW should provide much the same \
     * functionality in terms of which blocks to enter, so any messing \
     * about with except_state in here would indicate that THROW is \
     * doing the wrong thing.                   \
     */                     \
    longjmp(except_ch.except_jmp,1);            \
}

ScsiBoundsError

#define ScsiBoundsError   7

Index is out of range. An attempt was made to read past the end of a buffer. This error is specific to SCSI data transfers where for some CDBs it is normal that the data PDU might be short. I.e. ReportLuns initially called with allocation_length=8, just enough to get the "size" of lun list back after which the initiator will reissue the command with an allocation_length that is big enough.

THROW_MESSAGE_ON

#define THROW_MESSAGE_ON	(		cond,
			x,
			y
	)

Value:

    G_STMT_START { \
    if ((cond)) \
        except_throw(XCEPT_GROUP_WIRESHARK, (x), (y)); \
} G_STMT_END

THROW_ON

#define THROW_ON	(		cond,
			x
	)

Value:

    G_STMT_START { \
    if ((cond)) \
        except_throw(XCEPT_GROUP_WIRESHARK, (x), NULL); \
} G_STMT_END

TRY

#define TRY

Value:

{\
    except_t *volatile exc; \
    volatile int except_state = 0; \
    static const except_id_t catch_spec[] = { \
        { XCEPT_GROUP_WIRESHARK, XCEPT_CODE_ANY } }; \
    except_try_push(catch_spec, 1, &exc); \
                                                   \
    if(except_state & EXCEPT_CAUGHT)               \
        except_state |= EXCEPT_RETHROWN;           \
    except_state &= ~EXCEPT_CAUGHT;                \
                                                   \
    if (except_state == 0 && exc == 0)             \
        /* user's code goes here */

TypeError

#define TypeError   5

During dfilter parsing