libreswan/libreswan-4.4-getaddrinfo.patch

diff -up ./lib/libswan/ttoaddress.c.getaddrinfo ./lib/libswan/ttoaddress.c
--- ./lib/libswan/ttoaddress.c.getaddrinfo	2021-04-22 17:24:33.000000000 +0200
+++ ./lib/libswan/ttoaddress.c	2021-07-22 13:16:19.073745043 +0200
@@ -20,6 +20,7 @@
 #include <netdb.h>		/* for gethostbyname2() */
 
 #include "ip_address.h"
+#include "ip_sockaddr.h"
 #include "ip_info.h"
 #include "lswalloc.h"		/* for alloc_things(), pfree() */
 #include "lswlog.h"		/* for pexpect() */
@@ -75,56 +76,6 @@ static err_t ttoaddr_base(shunk_t src,
 }
 
 /*
- * tryname - try it as a name
- *
- * Error return is intricate because we cannot compose a static string.
- */
-static err_t tryname(const char *p,
-		     int af,
-		     int suggested_af,	/* kind(s) of numeric addressing tried */
-		     ip_address *dst)
-{
-	struct hostent *h = gethostbyname2(p, af);
-	if (h != NULL) {
-		if (h->h_addrtype != af) {
-			return "address-type mismatch from gethostbyname2!!!";
-		}
-
-		return data_to_address(h->h_addr, h->h_length, aftoinfo(af), dst);
-	}
-
-	if (af == AF_INET6) {
-		if (suggested_af == AF_INET6) {
-			return "not a numeric IPv6 address and name lookup failed (no validation performed)";
-		} else /* AF_UNSPEC */ {
-			return "not a numeric IPv4 or IPv6 address and name lookup failed (no validation performed)";
-		}
-	}
-
-	pexpect(af == AF_INET);
-
-	/* like, windows even has an /etc/networks? */
-	struct netent *ne = getnetbyname(p);
-	if (ne == NULL) {
-		/* intricate because we cannot compose a static string */
-		if (suggested_af == AF_INET) {
-			return "not a numeric IPv4 address and name lookup failed (no validation performed)";
-		} else {
-			return "not a numeric IPv4 or IPv6 address and name lookup failed (no validation performed)";
-		}
-	}
-
-	if (ne->n_addrtype != af) {
-		return "address-type mismatch from getnetbyname!!!";
-	}
-
-	/* apparently .n_net is in host order */
-	struct in_addr in = { htonl(ne->n_net), };
-	*dst = address_from_in_addr(&in);
-	return NULL;
-}
-
-/*
  * tryhex - try conversion as an eight-digit hex number (AF_INET only)
  */
 
@@ -401,57 +352,56 @@ err_t getpiece(const char **srcp,	/* *sr
 
 err_t ttoaddress_dns(shunk_t src, const struct ip_info *afi, ip_address *dst)
 {
+	char *name = clone_hunk_as_string(src, "ttoaddress_dns"); /* must free */
+	struct addrinfo *res = NULL;
+	const struct addrinfo hints = (struct addrinfo) {
+		.ai_family = afi == NULL ? AF_UNSPEC : afi->af,
+	};
 	*dst = unset_address;
-	if (src.len == 0) {
-		return "empty string";
-	}
-
-	bool was_numeric = true;
-	err_t err = ttoaddr_base(src, afi, &was_numeric, dst);
-	if (was_numeric) {
-		/* no-point in continuing */
-		return err;
-	}
 
-	/* err == non-numeric */
+	int eai = getaddrinfo(name, NULL, &hints, &res);
+	err_t err = NULL;
 
-	for (const char *cp = src.ptr, *end = cp + src.len; cp < end; cp++) {
+	if (eai != 0) {
 		/*
-		 * Legal ASCII characters in a domain name.
-		 * Underscore technically is not, but is a common
-		 * misunderstanding.  Non-ASCII characters are simply
-		 * exempted from checking at the moment, to allow for
-		 * UTF-8 encoded stuff; the purpose of this check is
-		 * merely to catch blatant errors.
-		 *
-		 * XXX: Suspect the ISASCII() check can be dropped -
-		 * utf-8 isn't allowed in DNS names and without a
-		 * utf-8 parser the check is flawed.
+		 * return system-supplied diagnostic
+		 * except where it is particularly confusing.
+		 * "Name or service not unknown." is terrible.
 		 */
-		static const char namechars[] =
-			"abcdefghijklmnopqrstuvwxyz0123456789ABCDEFGHIJKLMNOPQRSTUVWXYZ-_.";
-#define ISASCII(c) (((c) & 0x80) == 0)
-		if (ISASCII(*cp) && strchr(namechars, *cp) == NULL) {
-			return "illegal (non-DNS-name) character in name";
+		err = eai == EAI_NONAME ? "NAME is unknown" : gai_strerror(eai);
+	} else if (res == NULL) {
+		err = "not a numeric IP address and name lookup failed (no validation performed)";
+	} else {
+		/* always choose IPv4 result if there is one */
+		struct addrinfo *winner = res;
+
+		for (struct addrinfo *r = res; r!= NULL; r = r->ai_next) {
+			if (r->ai_family == AF_INET) {
+				winner = r;
+				break;
+			}
+ 		}
+
+		ip_port mbz = { .hport = 0 };
+		ip_sockaddr sa = {
+			.len = winner->ai_addrlen,
+		};
+		passert(sizeof(sa.sa) >= winner->ai_addrlen);
+		memcpy(&sa.sa, winner->ai_addr, winner->ai_addrlen);
+		passert(sa.sa.sa.sa_family == winner->ai_family);
+		/* boneheaded getaddrinfo(3) leaves port field uninitialized */
+		if (winner->ai_family == AF_INET) {
+			sa.sa.sin.sin_port = 0;
+		} else if (winner->ai_family == AF_INET6) {
+			sa.sa.sin6.sin6_port = 0;
+		} else {
+			bad_case(winner->ai_family);
 		}
+		err = sockaddr_to_address_port(sa, dst, &mbz);
+		passert(hport(mbz) == 0);
 	}
 
-	/*
-	 * need a guarenteed null terminated string
-	 */
-	char *name = clone_hunk_as_string(src, "ttoaddress_dns"); /* must free */
-	int suggested_af = afi == NULL ? AF_UNSPEC : afi->af;
-	err_t v4err = NULL, v6err = NULL;
-	if (err && (suggested_af == AF_UNSPEC || suggested_af == AF_INET)) {
-		err = v4err = tryname(name, AF_INET, suggested_af, dst);
-	}
-	if (err && (suggested_af == AF_UNSPEC || suggested_af == AF_INET6)) {
-		err = v6err = tryname(name, AF_INET6, suggested_af, dst);
-	}
-	/* prefer the IPv4 error */
-	if (err != NULL && v4err != NULL) {
-		err = v4err;
-	}
+	freeaddrinfo(res);
 	pfree(name);
 	return err;
 }