HEX
Server: nginx/1.28.3
System: Linux ip-172-31-12-242 6.17.0-1007-aws #7~24.04.1-Ubuntu SMP Thu Jan 22 21:04:49 UTC 2026 x86_64
User: root (0)
PHP: 7.4.33
Disabled: passthru,exec,system,putenv,chroot,chgrp,chown,shell_exec,popen,proc_open,pcntl_exec,ini_alter,ini_restore,dl,openlog,syslog,readlink,symlink,popepassthru,pcntl_alarm,pcntl_fork,pcntl_waitpid,pcntl_wait,pcntl_wifexited,pcntl_wifstopped,pcntl_wifsignaled,pcntl_wifcontinued,pcntl_wexitstatus,pcntl_wtermsig,pcntl_wstopsig,pcntl_signal,pcntl_signal_dispatch,pcntl_get_last_error,pcntl_strerror,pcntl_sigprocmask,pcntl_sigwaitinfo,pcntl_sigtimedwait,pcntl_exec,pcntl_getpriority,pcntl_setpriority,imap_open,apache_setenv
Upload Files
File: //usr/local/openssl/man/man3/BN_mod_word.3
.\" -*- mode: troff; coding: utf-8 -*-
.\" Automatically generated by Pod::Man 5.01 (Pod::Simple 3.43)
.\"
.\" Standard preamble:
.\" ========================================================================
.de Sp \" Vertical space (when we can't use .PP)
.if t .sp .5v
.if n .sp
..
.de Vb \" Begin verbatim text
.ft CW
.nf
.ne \\$1
..
.de Ve \" End verbatim text
.ft R
.fi
..
.\" \*(C` and \*(C' are quotes in nroff, nothing in troff, for use with C<>.
.ie n \{\
.    ds C` ""
.    ds C' ""
'br\}
.el\{\
.    ds C`
.    ds C'
'br\}
.\"
.\" Escape single quotes in literal strings from groff's Unicode transform.
.ie \n(.g .ds Aq \(aq
.el       .ds Aq '
.\"
.\" If the F register is >0, we'll generate index entries on stderr for
.\" titles (.TH), headers (.SH), subsections (.SS), items (.Ip), and index
.\" entries marked with X<> in POD.  Of course, you'll have to process the
.\" output yourself in some meaningful fashion.
.\"
.\" Avoid warning from groff about undefined register 'F'.
.de IX
..
.nr rF 0
.if \n(.g .if rF .nr rF 1
.if (\n(rF:(\n(.g==0)) \{\
.    if \nF \{\
.        de IX
.        tm Index:\\$1\t\\n%\t"\\$2"
..
.        if !\nF==2 \{\
.            nr % 0
.            nr F 2
.        \}
.    \}
.\}
.rr rF
.\" ========================================================================
.\"
.IX Title "BN_add_word 3"
.TH BN_add_word 3 2019-12-20 1.0.2u OpenSSL
.\" For nroff, turn off justification.  Always turn off hyphenation; it makes
.\" way too many mistakes in technical documents.
.if n .ad l
.nh
.SH NAME
BN_add_word, BN_sub_word, BN_mul_word, BN_div_word, BN_mod_word \- arithmetic
functions on BIGNUMs with integers
.SH SYNOPSIS
.IX Header "SYNOPSIS"
.Vb 1
\& #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);
.Ve
.SH DESCRIPTION
.IX Header "DESCRIPTION"
These functions perform arithmetic operations on BIGNUMs with unsigned
integers. They are much more efficient than the normal BIGNUM
arithmetic operations.
.PP
\&\fBBN_add_word()\fR adds \fBw\fR to \fBa\fR (\f(CW\*(C`a+=w\*(C'\fR).
.PP
\&\fBBN_sub_word()\fR subtracts \fBw\fR from \fBa\fR (\f(CW\*(C`a\-=w\*(C'\fR).
.PP
\&\fBBN_mul_word()\fR multiplies \fBa\fR and \fBw\fR (\f(CW\*(C`a*=w\*(C'\fR).
.PP
\&\fBBN_div_word()\fR divides \fBa\fR by \fBw\fR (\f(CW\*(C`a/=w\*(C'\fR) and returns the remainder.
.PP
\&\fBBN_mod_word()\fR returns the remainder of \fBa\fR divided by \fBw\fR (\f(CW\*(C`a%w\*(C'\fR).
.PP
For \fBBN_div_word()\fR and \fBBN_mod_word()\fR, \fBw\fR must not be 0.
.SH "RETURN VALUES"
.IX Header "RETURN VALUES"
\&\fBBN_add_word()\fR, \fBBN_sub_word()\fR and \fBBN_mul_word()\fR return 1 for success, 0
on error. The error codes can be obtained by \fBERR_get_error\fR\|(3).
.PP
\&\fBBN_mod_word()\fR and \fBBN_div_word()\fR return \fBa\fR%\fBw\fR on success and
\&\fB(BN_ULONG)\-1\fR if an error occurred.
.SH "SEE ALSO"
.IX Header "SEE ALSO"
\&\fBbn\fR\|(3), \fBERR_get_error\fR\|(3), \fBBN_add\fR\|(3)
.SH HISTORY
.IX Header "HISTORY"
\&\fBBN_add_word()\fR and \fBBN_mod_word()\fR are available in all versions of
SSLeay and OpenSSL. \fBBN_div_word()\fR was added in SSLeay 0.8, and
\&\fBBN_sub_word()\fR and \fBBN_mul_word()\fR in SSLeay 0.9.0.
.PP
Before 0.9.8a the return value for \fBBN_div_word()\fR and \fBBN_mod_word()\fR
in case of an error was 0.