From: Vitaliy Makkoveev <mvs@openbsd.org>
Subject: Re: npppd convert to imsg_get_fd()
To: yasuoka@openbsd.org, tech@openbsd.org
Date: Wed, 17 Jan 2024 16:50:00 +0300

On Wed, Jan 17, 2024 at 11:08:46AM +0100, Claudio Jeker wrote:
> Same conversions away from imsg.fd to imsg_get_fd().
> 
> This code base is a bit different to other imsg daemons but I think
> the conversion is still rather simple. This needs a local variable fd
> since the fd is accessed multiple times.
> 
> This was only compile tested since I no longer use npppd.

Works for me. ok mvs

> -- 
> :wq Claudio
> 
> Index: npppd/privsep.c
> ===================================================================
> RCS file: /cvs/src/usr.sbin/npppd/npppd/privsep.c,v
> diff -u -p -r1.24 privsep.c
> --- npppd/privsep.c	23 Jan 2020 00:17:27 -0000	1.24
> +++ npppd/privsep.c	13 Dec 2023 13:06:53 -0000
> @@ -526,7 +526,7 @@ privsep_recvfd(void)
>  		if (r->retval != 0)
>  			errno = r->rerrno;
>  		else
> -			retval = imsg.fd;
> +			retval = imsg_get_fd(&imsg);
>  	}
>  	imsg_free(&imsg);
>  
> @@ -646,18 +646,19 @@ privsep_priv_dispatch_imsg(struct imsgbu
>  		case PRIVSEP_BIND: {
>  			struct PRIVSEP_BIND_ARG	*a = imsg.data;
>  			struct PRIVSEP_COMMON_RESP r = { -1, 0 };
> +			int fd;
>  
>  			if (imsg.hdr.len != IMSG_HEADER_SIZE + sizeof(*a) ||
> -			    imsg.fd < 0)
> +			    (fd = imsg_get_fd(&imsg)) < 0)
>  				r.rerrno = EINVAL;
>  			else if (privsep_npppd_check_bind(a))
>  				r.rerrno = EACCES;
>  			else {
> -				if ((r.retval = bind(imsg.fd,
> +				if ((r.retval = bind(fd,
>  				    (struct sockaddr *)&a->name, a->namelen))
>  				    != 0)
>  					r.rerrno = errno;
> -				close(imsg.fd);
> +				close(fd);
>  			}
>  			(void)imsg_compose(ibuf, PRIVSEP_OK, 0, 0, -1,
>  			    &r, sizeof(r));
> @@ -744,28 +745,29 @@ on_broken_entry:
>  		case PRIVSEP_SENDTO: {
>  			struct PRIVSEP_SENDTO_ARG *a = imsg.data;
>  			struct PRIVSEP_COMMON_RESP r = { -1, 0 };
> +			int fd;
>  
>  			if (imsg.hdr.len < IMSG_HEADER_SIZE + sizeof(*a) ||
>  			    imsg.hdr.len < IMSG_HEADER_SIZE +
>  				offsetof(struct PRIVSEP_SENDTO_ARG,
>  					msg[a->len]))
>  				r.rerrno = EMSGSIZE;
> -			else if (imsg.fd < 0)
> +			else if ((fd = imsg_get_fd(&imsg)) < 0)
>  				r.rerrno = EINVAL;
>  			else if (privsep_npppd_check_sendto(a))
>  				r.rerrno = EACCES;
>  			else {
>  				if (a->tolen > 0)
> -					r.retval = sendto(imsg.fd, a->msg,
> +					r.retval = sendto(fd, a->msg,
>  					    a->len, a->flags,
>  					    (struct sockaddr *)&a->to,
>  					    a->tolen);
>  				else
> -					r.retval = send(imsg.fd, a->msg, a->len,
> +					r.retval = send(fd, a->msg, a->len,
>  					    a->flags);
>  				if (r.retval < 0)
>  					r.rerrno = errno;
> -				close(imsg.fd);
> +				close(fd);
>  			}
>  			(void)imsg_compose(ibuf, PRIVSEP_OK, 0, 0, -1,
>  			    &r, sizeof(r));
>