On Fri, 02 Jan 2026 16:50:18 +0100,
Martijn van Duren <openbsd+tech@list.imperialat.at> wrote:
> 
> According to RFC5321 section 4.5.3.1.10 the correct return code for too
> many recipients is 452. We currently return 451.
> 
> OK?
>

Make sense, OK kirill@

> martijn@
> 
> diff /usr/src
> path + /usr/src
> commit - b9146a17035f22954d6f1be04af1b32218d3b317
> blob - 195e75ec10fb05d4d30390a53c5ce5729b931505
> file + usr.sbin/smtpd/smtp_session.c
> --- usr.sbin/smtpd/smtp_session.c
> +++ usr.sbin/smtpd/smtp_session.c
> @@ -1593,7 +1593,7 @@ smtp_check_rcpt_to(struct smtp_session *s, const char 
>  	}
>  
>  	if (s->tx->rcptcount >= env->sc_session_max_rcpt) {
> -		smtp_reply(s->tx->session, "451 %s %s: Too many recipients",
> +		smtp_reply(s->tx->session, "452 %s %s: Too many recipients",
>  		    esc_code(ESC_STATUS_TEMPFAIL, ESC_TOO_MANY_RECIPIENTS),
>  		    esc_description(ESC_TOO_MANY_RECIPIENTS));
>  		return 0;
> @@ -2434,7 +2434,7 @@ smtp_tx_rcpt_to(struct smtp_tx *tx, const char *line)
>  	copy = tmp;
>  
>  	if (tx->rcptcount >= env->sc_session_max_rcpt) {
> -		smtp_reply(tx->session, "451 %s %s: Too many recipients",
> +		smtp_reply(tx->session, "452 %s %s: Too many recipients",
>  		    esc_code(ESC_STATUS_TEMPFAIL, ESC_TOO_MANY_RECIPIENTS),
>  		    esc_description(ESC_TOO_MANY_RECIPIENTS));
>  		return;
> 

-- 
wbr, Kirill