From: Klemens Nanni <kn@openbsd.org>
Subject: Re: remove host, host_v4 and host_v6; rename host_dns -> host
To: Omar Polo <op@omarpolo.com>, gameoftrees@openbsd.org
Date: Mon, 29 May 2023 17:24:37 +0000

On Mon, May 29, 2023 at 06:35:02PM +0200, Omar Polo wrote:
> This is an attempt at simplifying how host() works.  host() is used in
> the configuration file via get_addrs() to prepare a struct address
> after a "listen on" directive
> 
> The current code first tries to resolve it as an ipv4 address via
> inet_pton(), then as an ipv6 address using getaddrinfo() with
> AI_NUMERICHOST, then as an interface name and finally as a name to
> resolve via getaddrinfo() again.
> 
> Instead, scratch host(), host_v4() and host_v6() and rename host_dns()
> to host().  It preserve the lookup via interface name, and then uses
> getaddrinfo() only once wich already knows how to deal with IPv4/v6
> literals and resolving addresses too.

Did got copy this code from somewhere initially?

I recall doing this kind of host*() cleanup back in 2018 for base;
afaict all got cleaned up/unified eventually, so there should be a few
programs (with their own nuances) to compare against.

> 
> ok?
> 
> 
> diff 1adf41e8089257344579fba9c7e03d7ebc0c15b8 748f613ecec2c026f9351e11e7f25fd19d71e9d6
> commit - 1adf41e8089257344579fba9c7e03d7ebc0c15b8
> commit + 748f613ecec2c026f9351e11e7f25fd19d71e9d6
> blob - 3b73a07923fb6fec5efd9fea7f055fc7f917cfae
> blob + d01669e79c40ee6a64a1ed544069b368ac00bac0
> --- gotwebd/parse.y
> +++ gotwebd/parse.y
> @@ -99,14 +99,10 @@ struct address	*host_v4(const char *);
>  int		 addr_dup_check(struct addresslist *, struct address *,
>  		    const char *, const char *);
>  int		 add_addr(struct server *, struct address *);
> -struct address	*host_v4(const char *);
> -struct address	*host_v6(const char *);
> -int		 host_dns(const char *, struct server *,
> -		    int, in_port_t, const char *, int);
> -int		 host_if(const char *, struct server *,
> -		    int, in_port_t, const char *, int);
>  int		 host(const char *, struct server *,
>  		    int, in_port_t, const char *, int);
> +int		 host_if(const char *, struct server *,
> +		    int, in_port_t, const char *, int);
>  int		 is_if_in_group(const char *, const char *);
>  
>  typedef struct {
> @@ -1001,50 +997,8 @@ struct address *
>  	return (unsigned short)llval;
>  }
>  
> -struct address *
> -host_v4(const char *s)
> -{
> -	struct in_addr ina;
> -	struct sockaddr_in *sain;
> -	struct address *h;
> -
> -	memset(&ina, 0, sizeof(ina));
> -	if (inet_pton(AF_INET, s, &ina) != 1)
> -		return (NULL);
> -
> -	if ((h = calloc(1, sizeof(*h))) == NULL)
> -		fatal(__func__);
> -	sain = (struct sockaddr_in *)&h->ss;
> -	got_sockaddr_inet_init(sain, &ina);
> -	return (h);
> -}
> -
> -struct address *
> -host_v6(const char *s)
> -{
> -	struct addrinfo hints, *res;
> -	struct sockaddr_in6 *sa_in6, *ra;
> -	struct address *h = NULL;
> -
> -	memset(&hints, 0, sizeof(hints));
> -	hints.ai_family = AF_INET6;
> -	hints.ai_socktype = SOCK_DGRAM; /* dummy */
> -	hints.ai_flags = AI_NUMERICHOST;
> -	if (getaddrinfo(s, "0", &hints, &res) == 0) {
> -		if ((h = calloc(1, sizeof(*h))) == NULL)
> -			fatal(__func__);
> -		sa_in6 = (struct sockaddr_in6 *)&h->ss;
> -		ra = (struct sockaddr_in6 *)res->ai_addr;
> -		got_sockaddr_inet6_init(sa_in6, &ra->sin6_addr,
> -		    ra->sin6_scope_id);
> -		freeaddrinfo(res);
> -	}
> -
> -	return (h);
> -}
> -
>  int
> -host_dns(const char *s, struct server *new_srv, int max,
> +host(const char *s, struct server *new_srv, int max,
>      in_port_t port, const char *ifname, int ipproto)
>  {
>  	struct addrinfo hints, *res0, *res;
> @@ -1190,41 +1144,6 @@ host(const char *s, struct server *new_srv, int max,
>  }
>  
>  int
> -host(const char *s, struct server *new_srv, int max,
> -    in_port_t port, const char *ifname, int ipproto)
> -{
> -	struct address *h;
> -
> -	h = host_v4(s);
> -
> -	/* IPv6 address? */
> -	if (h == NULL)
> -		h = host_v6(s);
> -
> -	if (h != NULL) {
> -		if (port)
> -			h->port = port;
> -		if (ifname != NULL) {
> -			if (strlcpy(h->ifname, ifname, sizeof(h->ifname)) >=
> -			    sizeof(h->ifname)) {
> -				log_warnx("%s: interface name truncated",
> -				    __func__);
> -				free(h);
> -				return (-1);
> -			}
> -		}
> -		if (ipproto != -1)
> -			h->ipproto = ipproto;
> -
> -		if (add_addr(new_srv, h))
> -			return -1;
> -		return (1);
> -	}
> -
> -	return (host_dns(s, new_srv, max, port, ifname, ipproto));
> -}
> -
> -int
>  is_if_in_group(const char *ifname, const char *groupname)
>  {
>  	unsigned int len;
>