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scan_asn1derlength(3)	   Library Functions Manual	 scan_asn1derlength(3)

NAME
       scan_asn1derlengthvalue	-  decode  an  unsigned	integer	from ASN.1 DER
       length encoding

SYNTAX
       #include	<scan.h>

       size_t scan_asn1derlengthvalue(const char *src,size_t len,unsigned long
       long *dest);

DESCRIPTION
       scan_asn1derlengthvalue decodes an unsigned integer in ASN.1 DER	length
       encoding	from a memory area holding binary data.	 It writes the	decode
       value in	dest and returns the number of bytes it	read from src.

       scan_asn1derlength  never  reads	 more than len bytes from src.	If the
       sequence	is longer than that, or	the memory area	 contains  an  invalid
       sequence, scan_asn1derlength returns 0 and does not touch dest.

       The length of the longest spec-compliant	ASN.1 DER length is 128	bytes,
       but this	implementation will return an error if the value does not  fit
       into  the  target  integer  type.   In practice the largest sequence is
       sizeof(*dest)+1.

       This implementation will	reject values that are not encoded in the min-
       imum amount of bytes.

       If  you	need  to decode	the length value so you	can parse actual ASN.1
       tag/length/value	structures, please consider  using  scan_asn1derlength
       instead,	as it will do additional checking for you.

SEE ALSO
       fmt_asn1derlength(3), scan_asn1derlengthvalue(3)

							 scan_asn1derlength(3)

NAME | SYNTAX | DESCRIPTION | SEE ALSO

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