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);
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
hexadecimal and decimal encoding of a respectively. For negative numbers, the
string is prefaced with a leading '-'. The string must be freed later
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
BN_print() and BN_print_fp() write the hexadecimal encoding of
a, with a leading '-' for negative
numbers, to the BIO or FILEfp.
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 null 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_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
BN_bn2bin() returns the length of the big-endian number placed at
to. BN_bin2bn() returns the
BIGNUM, NULL on error.
BN_bn2hex() and BN_bn2dec() return a null-terminated string, or NULL
on error. BN_hex2bn() and BN_dec2bn() return the number's length in
hexadecimal or decimal digits, and 0 on error.
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, and NULL on