asn1_read_value(3) [debian man page]
asn1_read_value(3) libtasn1 asn1_read_value(3) NAME
asn1_read_value - API function SYNOPSIS
#include <libtasn1.h> asn1_retCode asn1_read_value(ASN1_TYPE root, const char * name, void * ivalue, int * len); ARGUMENTS
ASN1_TYPE root pointer to a structure. const char * name the name of the element inside a structure that you want to read. void * ivalue vector that will contain the element's content, must be a pointer to memory cells already allocated. int * len number of bytes of *value: value[0]..value[len-1]. Initialy holds the sizeof value. DESCRIPTION
Returns the value of one element inside a structure. If an element is OPTIONAL and the function "read_value" returns ASN1_ELEMENT_NOT_FOUND, it means that this element wasn't present in the der encoding that created the structure. The first element of a SEQUENCE_OF or SET_OF is named "?1". The second one "?2" and so on. INTEGER
VALUE will contain a two's complement form integer. integer=-1 -> value[0]=0xFF , len=1. integer=1 -> value[0]=0x01 , len=1. ENUMERATED
As INTEGER (but only with not negative numbers). BOOLEAN
VALUE will be the null terminated string "TRUE" or "FALSE" and LEN=5 or LEN=6. OBJECT IDENTIFIER
VALUE will be a null terminated string with each number separated by a dot (i.e. "1.2.3.543.1"). LEN = strlen(VALUE)+1 UTCTIME
VALUE will be a null terminated string in one of these formats: "YYMMDDhhmmss+hh'mm'" or "YYMMDDhhmmss-hh'mm'". LEN=strlen(VALUE)+1. GENERALIZEDTIME
VALUE will be a null terminated string in the same format used to set the value. OCTET STRING
VALUE will contain the octet string and LEN will be the number of octets. GENERALSTRING
VALUE will contain the generalstring and LEN will be the number of octets. BIT STRING
VALUE will contain the bit string organized by bytes and LEN will be the number of bits. CHOICE
If NAME indicates a choice type, VALUE will specify the alternative selected. ANY
If NAME indicates an any type, VALUE will indicate the DER encoding of the structure actually used. RETURNS
ASN1_SUCCESS if value is returned, ASN1_ELEMENT_NOT_FOUND if name is not a valid element, ASN1_VALUE_NOT_FOUND if there isn't any value for the element selected, and ASN1_MEM_ERROR if The value vector isn't big enough to store the result, and in this case len will contain the number of bytes needed. COPYRIGHT
Copyright (C) 2006-2011 Free Software Foundation, Inc.. Copying and distribution of this file, with or without modification, are permitted in any medium without royalty provided the copyright notice and this notice are preserved. SEE ALSO
The full documentation for libtasn1 is maintained as a Texinfo manual. If the info and libtasn1 programs are properly installed at your site, the command info libtasn1 should give you access to the complete manual. libtasn1 2.13 asn1_read_value(3)
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asn1_write_value(3) libtasn1 asn1_write_value(3) NAME
asn1_write_value - API function SYNOPSIS
#include <libtasn1.h> asn1_retCode asn1_write_value(ASN1_TYPE node_root, const char * name, const void * ivalue, int len); ARGUMENTS
ASN1_TYPE node_root pointer to a structure const char * name the name of the element inside the structure that you want to set. const void * ivalue vector used to specify the value to set. If len is >0, VALUE must be a two's complement form integer. if len=0 *VALUE must be a null terminated string with an integer value. int len number of bytes of *value to use to set the value: value[0]..value[len-1] or 0 if value is a null terminated string DESCRIPTION
Set the value of one element inside a structure. If an element is OPTIONAL and you want to delete it, you must use the value=NULL and len=0. Using "pkix.asn": result=asn1_write_value(cert, "tbsCertificate.issuerUniqueID", NULL, 0); DESCRIPTION FOR EACH TYPE
INTEGER
VALUE must contain a two's complement form integer. value[0]=0xFF , len=1 -> integer=-1. value[0]=0xFF value[1]=0xFF , len=2 -> integer=-1. value[0]=0x01 , len=1 -> integer= 1. value[0]=0x00 value[1]=0x01 , len=2 -> integer= 1. value="123" , len=0 -> integer= 123. ENUMERATED
As INTEGER (but only with not negative numbers). BOOLEAN
VALUE must be the null terminated string "TRUE" or "FALSE" and LEN != 0. value="TRUE" , len=1 -> boolean=TRUE. value="FALSE" , len=1 -> boolean=FALSE. OBJECT IDENTIFIER
VALUE must be a null terminated string with each number separated by a dot (e.g. "1.2.3.543.1"). LEN != 0. value="1 2 840 10040 4 3" , len=1 -> OID=dsa-with-sha. UTCTIME
VALUE must be a null terminated string in one of these formats: "YYMMDDhhmmssZ", "YYMMDDhhmmssZ", "YYMMDDhhmmss+hh'mm'", "YYMMDDhh- mmss-hh'mm'", "YYMMDDhhmm+hh'mm'", or "YYMMDDhhmm-hh'mm'". LEN != 0. value="9801011200Z" , len=1 -> time=Jannuary 1st, 1998 at 12h 00m Greenwich Mean Time GENERALIZEDTIME
VALUE must be in one of this format: "YYYYMMDDhhmmss.sZ", "YYYYMMDDhhmmss.sZ", "YYYYMMDDhhmmss.s+hh'mm'", "YYYYMMDDhhmmss.s-hh'mm'", "YYYYMMDDhhmm+hh'mm'", or "YYYYMMDDhhmm-hh'mm'" where ss.s indicates the seconds with any precision like "10.1" or "01.02". LEN != 0 value="2001010112001.12-0700" , len=1 -> time=Jannuary 1st, 2001 at 12h 00m 01.12s Pacific Daylight Time OCTET STRING
VALUE contains the octet string and LEN is the number of octets. value="$ssh$x01$ssh$x02$ssh$x03" , len=3 -> three bytes octet string l l l GENERALSTRING
VALUE coctains tce generclstring and LEN is the number of octets. k k k value="$ssh$x01$ssh$x02$ssh$x03" , len=3 -> three bytes generalstring l l l BIT STRING
VALUE coctains the bit string organized by bytes and LEN is the number of bits. k value="$ssh$xCF" , len=6 -> bit string="110011" (six bits) l CHOICE
if NAME indicates a choice type, VALUE must specify one of the alternatives with a null terminated string. LEN != 0. Using "pkix.asn" result=asn1_write_value(cert, "certificate1.tbsCertificate.subject", "rdnSequence", 1); ANY
VALUE indicates the der encoding of a structure. LEN != 0. SEQUENCE OF
VALUE must be the null terminated string "NEW" and LEN != 0. With this instruction another element is appended in the sequence. The name of this element will be "?1" if it's the first one, "?2" for the second and so on. Using "pkix.asn" result=asn1_write_value(cert, "certificate1.tbsCertificate.subject.rdnSequence", "NEW", 1); SET OF
the same as SEQUENCE OF. Using "pkix.asn": result=asn1_write_value(cert, "tbsCertificate.subject.rdnSequence.?LAST", "NEW", 1); RETURNS
ASN1_SUCCESS if the value was set, ASN1_ELEMENT_NOT_FOUND if name is not a valid element, and ASN1_VALUE_NOT_VALID if ivalue has a wrong format. COPYRIGHT
Copyright (C) 2006-2011 Free Software Foundation, Inc.. Copying and distribution of this file, with or without modification, are permitted in any medium without royalty provided the copyright notice and this notice are preserved. SEE ALSO
The full documentation for libtasn1 is maintained as a Texinfo manual. If the info and libtasn1 programs are properly installed at your site, the command info libtasn1 should give you access to the complete manual. libtasn1 2.13 asn1_write_value(3)