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BN_BN2BIN(3)	      DragonFly Library Functions Manual	  BN_BN2BIN(3)

NAME
     BN_bn2bin, BN_bin2bn, BN_bn2hex, BN_bn2dec, BN_hex2bn, BN_dec2bn,
     BN_asc2bn, BN_print, BN_print_fp, BN_bn2mpi, BN_mpi2bn -- format conver-
     sions

SYNOPSIS
     #include <openssl/bn.h>

     int
     BN_bn2bin(const BIGNUM *a, unsigned char *to);

     BIGNUM *
     BN_bin2bn(const unsigned char *s, int len, BIGNUM *ret);

     char *
     BN_bn2hex(const BIGNUM *a);

     char *
     BN_bn2dec(const BIGNUM *a);

     int
     BN_hex2bn(BIGNUM **a, const char *str);

     int
     BN_dec2bn(BIGNUM **a, const char *str);

     int
     BN_asc2bn(BIGNUM **a, const char *str);

     int
     BN_print(BIO *fp, const BIGNUM *a);

     int
     BN_print_fp(FILE *fp, const BIGNUM *a);

     int
     BN_bn2mpi(const BIGNUM *a, unsigned char *to);

     BIGNUM *
     BN_mpi2bn(unsigned char *s, int len, BIGNUM *ret);

DESCRIPTION
     BN_bn2bin() converts the absolute value of a into big-endian form and
     stores it at to.  to must point to BN_num_bytes(a) bytes of memory.

     BN_bin2bn() converts the positive integer in big-endian form of length
     len at s into a BIGNUM and places it in ret.  If ret is NULL, a new
     BIGNUM is created.

     BN_bn2hex() and BN_bn2dec() return printable strings containing the hexa-
     decimal and decimal encoding of a respectively.  For negative numbers,
     the string is prefaced with a leading minus sign.	The string must be
     freed later using free(3).

     BN_hex2bn() interprets str as a hexadecimal number.  The string may start
     with a minus sign (`-').  Conversion stops at the first byte that is not
     a hexadecimal digit.  The number is converted to a BIGNUM and stored in
     *a.  If *a is NULL, a new BIGNUM is created.  If a is NULL, it only com-
     putes the number's length in hexadecimal digits.  A "negative zero" is
     converted to zero.  BN_dec2bn() is the same using the decimal system.
     BN_asc2bn() infers the number base from an optional prefix.  If str
     starts with "0x" or "0X", it calls BN_hex2bn(), otherwise BN_dec2bn().
     If the number is negative, the minus sign can be given before or after
     the prefix.

     BN_print() and BN_print_fp() write the hexadecimal encoding of a, with a
     leading minus sign for negative numbers, to the BIO or FILE fp.

     BN_bn2mpi() and BN_mpi2bn() convert BIGNUMs from and to a format that
     consists of the number's length in bytes represented as a 4-byte big-
     endian number, and the number itself in big-endian format, where the most
     significant bit signals a negative number (the representation of numbers
     with the MSB set is prefixed with a NUL byte).

     BN_bn2mpi() stores the representation of a at to, where to must be large
     enough to hold the result.  The size can be determined by calling
     BN_bn2mpi(a, NULL).

     BN_mpi2bn() converts the len bytes long representation at s to a BIGNUM
     and stores it at ret, or in a newly allocated BIGNUM if ret is NULL.

RETURN VALUES
     BN_bn2bin() returns the length of the big-endian number placed at to.
     BN_bin2bn() returns the BIGNUM, or NULL on error.

     BN_bn2hex() and BN_bn2dec() return a NUL-terminated string, or NULL on
     error.  BN_hex2bn() and BN_dec2bn() return the number's length in hexa-
     decimal or decimal digits or 0 on error, in which case no new BIGNUM is
     created.  BN_asc2bn() returns 1 on success or 0 on error, in which case
     no new BIGNUM is created.

     BN_print_fp() and BN_print() return 1 on success, 0 on write errors.

     BN_bn2mpi() returns the length of the representation.  BN_mpi2bn()
     returns the BIGNUM, or NULL on error.

     The error codes can be obtained by ERR_get_error(3).

SEE ALSO
     BN_new(3), BN_num_bytes(3), BN_zero(3), ERR_get_error(3)

HISTORY
     BN_bn2bin(), BN_bin2bn(), and BN_print() first appeared in SSLeay 0.5.1.
     BN_print_fp() first appeared in SSLeay 0.6.0.  BN_bn2hex(), BN_bn2dec(),
     BN_hex2bn(), BN_dec2bn(), BN_bn2mpi(), and BN_mpi2bn() first appeared in
     SSLeay 0.9.0.  All these functions have been available since OpenBSD 2.4.

     BN_asc2bin() first appeared in OpenSSL 1.0.0 and has been available since
     OpenBSD 4.9.

DragonFly 5.5			March 27, 2018			 DragonFly 5.5