Bug Fix : OER constraint for asn1/its/Elevation.c + UPER contraints for ans1/its/DeltaReferencePositions & ans1/its/DeltaPositions #226
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| @@ -15,7 +15,7 @@ static asn_oer_constraints_t asn_OER_type_DeltaPositions_constr_1 CC_NOTUSED = { | |||
| #if !defined(ASN_DISABLE_UPER_SUPPORT) || !defined(ASN_DISABLE_APER_SUPPORT) | |||
| asn_per_constraints_t asn_PER_type_DeltaPositions_constr_1 CC_NOTUSED = { | |||
| { APC_UNCONSTRAINED, -1, -1, 0, 0 }, | |||
| { APC_CONSTRAINED | APC_EXTENSIBLE, 7, 7, 1, 100 } /* (SIZE(1..100,...)) */, | |||
| { APC_CONSTRAINED | APC_EXTENSIBLE, 5, 5, 1, 32 } /* (SIZE(1..100,...)) */, | |||
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We should not patch the generated sources but update the used ISO 19321 ASN.1 file which includes the changed sequence constraints. At the moment, we fetch "ed-2" in fetch_iso_asn1_files.cmake, the changed constraints are included in "ed-3".
| @@ -15,7 +15,7 @@ static asn_oer_constraints_t asn_OER_type_DeltaReferencePositions_constr_1 CC_NO | |||
| #if !defined(ASN_DISABLE_UPER_SUPPORT) || !defined(ASN_DISABLE_APER_SUPPORT) | |||
| asn_per_constraints_t asn_PER_type_DeltaReferencePositions_constr_1 CC_NOTUSED = { | |||
| { APC_UNCONSTRAINED, -1, -1, 0, 0 }, | |||
| { APC_CONSTRAINED | APC_EXTENSIBLE, 7, 7, 1, 100 } /* (SIZE(1..100,...)) */, | |||
| { APC_CONSTRAINED | APC_EXTENSIBLE, 5, 5, 1, 32 } /* (SIZE(1..32,...))*/, | |||
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Same here, update ISO 19321 ASN.1 used for code generation instead.
| @@ -38,7 +38,7 @@ Elevation_constraint(const asn_TYPE_descriptor_t *td, const void *sptr, | |||
| */ | |||
| #if !defined(ASN_DISABLE_OER_SUPPORT) | |||
| static asn_oer_constraints_t asn_OER_type_Elevation_constr_1 CC_NOTUSED = { | |||
| { 4, 0 } /* (-4096..61439) */, | |||
| { 2, 1 } /* (-4096..61439) */, | |||
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I see that the number of values fits in an uint16_t. Does asn1c already shift the values as expected, i.e. a raw 0 is decoded as -4096 in Elevation_t?
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Section 2.2 of https://www.oss.com/asn1/resources/books-whitepapers-pubs/Overview_of_OER.pdf summarizes the OER encoding rules for integer types. According to this summary, the Elevation type with a lower bound of -4096 and an upper bound of 61439 is encoded as a signed integer in four octets.
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see also ITU-T X.696 (02/2021) 10.4 c)
Elevation with given bounds must be encoded using 4 octets as signed integer.
Hello,
After this issue : #225. I've come accross to a bug, the Elevation.c in asn/its was causing a problem for the decoding of secured packet. I've just changed the OER constraint to limit potential repercussion outside of secured packet.
Also, I've discovered that when I receives IVIM packets with PolygonalLine/DeltaPositions_t I have problem decoding. It appears that the UPER constraint was wrong, I've only looked at DeltaPositions and DeltaReferencePositions.