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Alphabetical listing for B

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BN_bn2bin(3)
NAME
  BN_bn2bin, BN_bin2bn, BN_bn2hex, BN_bn2dec, BN_hex2bn, BN_dec2bn, BN_print,
  BN_print_fp, BN_bn2mpi, BN_mpi2bn - Format conversions

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

  The BN_bin2bn() function 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.

  The BN_bn2hex() and BN_bn2dec() functions return printable strings
  containing the hexadecimal and decimal encoding of a respectively. For
  negative numbers, the string is prefaced with a leading '-'. The string
  must be freed later using OPENSSL_free().

  BN_hex2bn() converts the string str containing a hexadecimal number to a
  BIGNUM and stores it in **bn. If *bn is NULL, a new BIGNUM is created. If
  bn is NULL, it only computes the number's length in hexadecimal digits. If
  the string starts with '-', the number is negative.  BN_dec2bn() is the
  same using the decimal system.

  The BN_print() and BN_print_fp() functions write the hexadecimal encoding
  of a, with a leading '-' for negative numbers, to the BIO or FILE fp.

  The BN_bn2mpi() and BN_mpi2bn() functions 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 null byte).

  The BN_bn2mpi() function 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).

  The BN_mpi2bn() function 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
  The BN_bn2bin() function returns the length of the big-endian number placed
  at to. The BN_bin2bn() function returns the BIGNUM, NULL on error.

  The BN_bn2hex() and BN_bn2dec() functions return a null-terminated string,
  or NULL on error. The BN_hex2bn() and BN_dec2bn() functions return the
  number's length in hexadecimal or decimal digits, and 0 on error.

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

  The BN_bn2mpi() function returns the length of the representation. The
  BN_mpi2bn() function returns the BIGNUM, and NULL on error.

  The error codes can be obtained by using the ERR_get_error() function.

HISTORY
  The BN_bn2bin(), BN_bin2bn(), BN_print_fp(), and BN_print() functions are
  available in all versions of SSLeay and OpenSSL.

  The BN_bn2hex(), BN_bn2dec(), BN_hex2bn(), BN_dec2bn(), BN_bn2mpi(), and
  BN_mpi2bn() functions were added in SSLeay 0.9.0.

SEE ALSO
  Functions: bn(3), err(3), BN_zero(3), ASN1_INTEGER_to_BN(3),
  BN_num_bytes(3)

Index for Section 3

Alphabetical listing for B

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