Use getaddrinfo() instead of the non-standard gethostbyname2().

OK deraadt@ jca@ jung@ florian@

1 files changed, 14 insertions, 5 deletions

diff --git a/src/lib/libc/net/rcmdsh.c b/src/lib/libc/net/rcmdsh.c
index 14275d414a..b9cbd6d5d1 100644
--- a/src/lib/libc/net/rcmdsh.c
+++ b/src/lib/libc/net/rcmdsh.c
@@ -1,4 +1,4 @@
-/*      $OpenBSD: rcmdsh.c,v 1.18 2015/11/24 22:03:33 millert Exp $     */ 
+/*      $OpenBSD: rcmdsh.c,v 1.19 2016/05/28 15:46:00 millert Exp $     */ 
 
 /*
  * Copyright (c) 2001, MagniComp
@@ -38,6 +38,7 @@
 #include      <sys/wait.h>
 #include      <signal.h>
 #include      <errno.h>
+#include      <limits.h>
 #include      <netdb.h>
 #include      <stdio.h>
 #include      <stdlib.h>
@@ -55,7 +56,8 @@ int
 rcmdsh(char **ahost, int rport, const char *locuser, const char *remuser,
     const char *cmd, char *rshprog)
 {
-        struct hostent *hp;
+        static char hbuf[HOST_NAME_MAX+1];
+        struct addrinfo hint, *res;
         int sp[2];
         pid_t cpid;
         char *p, pwbuf[_PW_BUF_LEN];
@@ -74,9 +76,16 @@ rcmdsh(char **ahost, int rport, const char *locuser, const char *remuser,
 
         /* Validate remote hostname. */
         if (strcmp(*ahost, "localhost") != 0) {
-                if ((hp = gethostbyname2(*ahost, AF_INET)) ||
-                    (hp = gethostbyname2(*ahost, AF_INET6)))
-                        *ahost = hp->h_name;
+                memset(&hint, 0, sizeof(hint));
+                hint.ai_family = PF_UNSPEC;
+                hint.ai_flags = AI_CANONNAME;
+                if (getaddrinfo(*ahost, NULL, &hint, &res) == 0) {
+                        if (res->ai_canonname) {
+                                strlcpy(hbuf, res->ai_canonname, sizeof(hbuf));
+                                *ahost = hbuf;
+                        }
+                        freeaddrinfo(res);
+                }
         }
 
         /* Get a socketpair we'll use for stdin and stdout. */