BN_ADD_WORD(3)             Library Functions Manual             BN_ADD_WORD(3)

NAME
     BN_add_word, BN_sub_word, BN_mul_word, BN_div_word, BN_mod_word -
     arithmetic functions on BIGNUMs with integers

SYNOPSIS
     #include <openssl/bn.h>

     int
     BN_add_word(BIGNUM *a, BN_ULONG w);

     int
     BN_sub_word(BIGNUM *a, BN_ULONG w);

     int
     BN_mul_word(BIGNUM *a, BN_ULONG w);

     BN_ULONG
     BN_div_word(BIGNUM *a, BN_ULONG w);

     BN_ULONG
     BN_mod_word(const BIGNUM *a, BN_ULONG w);

DESCRIPTION
     These functions perform arithmetic operations on BIGNUMs with unsigned
     integers.  They are much more efficient than the normal BIGNUM arithmetic
     operations.

     BN_ULONG is a macro that expands to unsigned long (= uint64_t) on _LP64
     platforms and unsigned int (= uint32_t) elsewhere.

     BN_add_word() adds w to a (a+=w).

     BN_sub_word() subtracts w from a (a-=w).

     BN_mul_word() multiplies a and w (a*=w).

     BN_div_word() divides a by w (a/=w) and returns the remainder.

     BN_mod_word() returns the remainder of a divided by w (a%w).

     For BN_div_word() and BN_mod_word(), w must not be 0.

RETURN VALUES
     BN_add_word(), BN_sub_word(), and BN_mul_word() return 1 for success or 0
     on error.  The error codes can be obtained by ERR_get_error(3).

     BN_mod_word() and BN_div_word() return a%w on success and (BN_ULONG)-1 if
     an error occurred.

SEE ALSO
     BN_add(3), BN_new(3)

HISTORY
     BN_add_word(), BN_div_word(), and BN_mod_word() first appeared in SSLeay
     0.5.1.  BN_sub_word() and BN_mul_word() first appeared in SSLeay 0.9.0.
     All these functions have been available since OpenBSD 2.4.

     Before 0.9.8a, the return value for BN_div_word() and BN_mod_word() in
     case of an error was 0.

Linux 6.8.2-arch2-1            November 22, 2022           Linux 6.8.2-arch2-1