ASN1_PARSE_DUMP(3)         Library Functions Manual         ASN1_PARSE_DUMP(3)

NAME
     ASN1_parse_dump, ASN1_parse - parse BER and print information about it

SYNOPSIS
     #include <openssl/asn1.h>

     int
     ASN1_parse_dump(BIO *bio, const unsigned char *ber_in, long length,
         int indent, int dump);

     int
     ASN1_parse(BIO *bio, const unsigned char *ber_in, long length,
         int indent);

DESCRIPTION
     ASN1_parse_dump() parses BER-encoded values and prints information about
     them to bio.  On function entry, *ber_in is expected to point to the
     first identifier octet of an encoded value.  At most length bytes are
     inspected.

     For each value successfully parsed, the following information is printed:

     1.   The index of its first identifier octet relative to ber_in as a
          decimal number followed by a colon.  For the first value parsed and
          printed, this is "0:".

     2.   The nesting depth as a decimal integer.  For the first value parsed
          and printed, this is "d=0".

     3.   The header length in bytes, including the identifier octets and the
          length octets, as a decimal integer.  For example, for a boolean
          value, this is "hl=2" because the encoding of a boolean value
          contains one identifier octet (0x01) and one length octet (also
          0x01, because one content octet follows after the header).

     4.   If the value is encoded using the definite form for the length
          octets, the number encoded in the length octets as a decimal
          integer.  This is the number of content octets that follow.  For
          example, for a boolean value, this is "l=1".  If the value is
          encoded using a length octet indicating the indefinite form, "l=inf"
          is printed instead.

     5.   If the value is primitive, "prim:" is printed; if it is constructed,
          "cons:".

     6.   The next field depends on the class of the tag:

          V_ASN1_PRIVATE
                  "priv" followed by the decimal tag number in square brackets

          V_ASN1_CONTEXT_SPECIFIC
                  "cont" followed by the decimal tag number in square brackets

          V_ASN1_APPLICATION
                  "appl" followed by the decimal tag number in square brackets

          V_ASN1_UNIVERSAL
                  If the tag number is 30 or less, the return value from
                  ASN1_tag2str(3) is printed; otherwise, "<ASN1" followed by
                  the decimal tag number and a closing angle bracket.

     For constructed values, the contained values are recursively printed.

     Primitive values are processed as follows:

     V_ASN1_BOOLEAN
             Its integer value is printed as a decimal number.

     V_ASN1_INTEGER
             Decoded with d2i_ASN1_INTEGER(3), printed as a hexadecimal number
             with an even number of digits.

     V_ASN1_ENUMERATED
             Decoded with d2i_ASN1_ENUMERATED(3), printed as a hexadecimal
             number with an even number of digits.

     V_ASN1_OBJECT
             Decoded with d2i_ASN1_OBJECT(3), printed with i2a_ASN1_OBJECT(3).

     V_ASN1_OCTET_STRING
             Decoded with d2i_ASN1_OCTET_STRING(3).  If the data consists only
             of printable ASCII characters, line feeds, carriage returns and
             horizontal tabs, it is printed as an ASCII string.

             Otherwise, the dump argument decides the format.  If it is zero,
             a raw hex dump is emitted, consisting of two hexadecimal digits
             for every data byte.  If dump is non-zero, BIO_dump_indent(3) is
             used.  Unless dump is -1, the data is truncated after dump bytes.

     V_ASN1_PRINTABLESTRING
             Printed as an ASCII string.  The same applies to
             V_ASN1_IA5STRING, V_ASN1_T61STRING, V_ASN1_NUMERICSTRING,
             V_ASN1_VISIBLESTRING, V_ASN1_UTF8STRING, V_ASN1_UTCTIME, and
             V_ASN1_GENERALIZEDTIME.

     Other tags
             If the dump argument is 0, their data is silently ignored.  If
             dump is non-zero, BIO_dump_indent(3) is used.  Unless dump is -1,
             the data is truncated after dump bytes.

     ASN1_parse() is identical to ASN1_parse_dump() with 0 passed as the dump
     argument.

RETURN VALUES
     These functions return 1 for success or 0 for failure.

     In particular, they print an error message to bio, abort parsing and
     printing, and return 0 when parsing or decoding fails, when a recursive
     call fails, when encountering a value extending beyond length, or when
     encountering a nesting level in excess of 128.  They also abort parsing
     and printing and return 0 when any printing operation fails.

SEE ALSO
     ASN1_get_object(3), ASN1_item_d2i(3), ASN1_item_new(3),
     ASN1_STRING_print(3), ASN1_TYPE_new(3)

STANDARDS
     ITU-T Recommendation X.690, also known as ISO/IEC 8825-1: Information
     technology - ASN.1 encoding rules: Specification of Basic Encoding Rules
     (BER), Canonical Encoding Rules (CER) and Distinguished Encoding Rules
     (DER), section 8.1: General rules for encoding

HISTORY
     ASN1_parse() first appeared in SSLeay 0.5.1 and has been available since
     OpenBSD 2.4.

     ASN1_parse_dump() first appeared in OpenSSL 0.9.6 and has been available
     since OpenBSD 2.9.

BUGS
     The content of values tagged as V_ASN1_BMPSTRING is silently ignored and
     none of it is printed.

Linux 6.8.2-arch2-1            December 9, 2021            Linux 6.8.2-arch2-1