Improve address type error handling

This patch detects numeric address types to avoid unnecessary
warnings/errors.  It also cleans up error printing to not print error
messages on stderr in the deamon case.

Signed-off-by: Karsten Keil <kkeil@suse.de>
Signed-off-by: H. Peter Anvin <hpa@zytor.com>

common/tftpsubs.c

@@ -310,15 +310,10 @@ set_sock_addr(char *host,union sock_addr  *s, char **name)
     hints.ai_family = s->sa.sa_family;
     hints.ai_flags = AI_CANONNAME;
     err = getaddrinfo(strip_address(host), NULL, &hints, &addrResult);
-    if (err) {
+    if (err)
-        printf("Error : %s\n", gai_strerror(err));
-        printf("%s: unknown host\n", host);
         return err;
-    }
+    if (addrResult == NULL)
-    if (addrResult == NULL) {
-        printf("%s: unknown host\n", host);
         return EAI_NONAME;
-    }
     memcpy(s, addrResult->ai_addr, addrResult->ai_addrlen);
     if (name) {
         if (addrResult->ai_canonname)

configure.in

@@ -175,6 +175,7 @@ then
     AC_SEARCH_LIBS(inet_ntoa, [nsl resolv], ,
       [AC_MSG_ERROR(inet_ntoa not found)])
 fi
+AC_SEARCH_LIBS(inet_aton, [nsl resolv], ,[AC_MSG_ERROR(inet_aton not found)])
 
 AC_CHECK_FUNCS(daemon, , [XTRA=true; AC_LIBOBJ(daemon)])
 AC_CHECK_FUNCS(dup2, , [XTRA=true; AC_LIBOBJ(dup2)])

tftp/main.c

@@ -416,6 +416,8 @@ void setpeer(int argc, char *argv[])
     peeraddr.sa.sa_family = ai_fam;
     err = set_sock_addr(argv[1], &peeraddr, &hostname);
     if (err) {
+        printf("Error: %s\n", gai_strerror(err));
+        printf("%s: unknown host\n", argv[1]);
         connected = 0;
         return;
     }
@@ -557,6 +559,8 @@ void put(int argc, char *argv[])
         peeraddr.sa.sa_family = ai_fam;
         err = set_sock_addr(cp, &peeraddr,&hostname);
         if (err) {
+            printf("Error: %s\n", gai_strerror(err));
+            printf("%s: unknown host\n", argv[1]);
             connected = 0;
             return;
         }
@@ -645,8 +649,11 @@ void get(int argc, char *argv[])
             *src++ = 0;
             peeraddr.sa.sa_family = ai_fam;
             err = set_sock_addr(argv[n], &peeraddr, &hostname);
-            if (err)
+            if (err) {
+                printf("Warning: %s\n", gai_strerror(err));
+                printf("%s: unknown host\n", argv[1]);
                 continue;
+            }
             ai_fam = peeraddr.sa.sa_family;
             connected = 1;
         }

tftpd/tftpd.c

@@ -258,23 +258,36 @@ static int recv_time(int s, void *rbuf, int len, unsigned int flags,
 static int split_port(char **ap, char **pp)
 {
     char *a, *p;
+    int  ret = AF_UNSPEC;
 
     a = *ap;
+#ifdef HAVE_IPV6
     if (is_numeric_ipv6(a)) {
         if (*a++ != '[')
-            return 1;
+            return -1;
         *ap = a;
         p = strrchr(a, ']');
         if (!p)
-            return 1;
+            return -1;
         *p++ = 0;
         a = p;
-    }
+        ret = AF_INET6;
         p = strrchr(a, ':');
         if (p)
             *p++ = 0;
+    } else
+#endif
+    {
+        struct in_addr in;
+
+        p = strrchr(a, ':');
+        if (p)
+            *p++ = 0;
+        if (inet_aton(a, &in))
+            ret = AF_INET;
+    }
     *pp = p;
-    return 0;
+    return ret;
 }
 
 enum long_only_options {
@@ -542,7 +555,26 @@ int main(int argc, char **argv)
 
             address = tfstrdup(address);
             err = split_port(&address, &portptr);
-            if (err) {
+            switch (err) {
+            case AF_INET:
+#ifdef HAVE_IPV6
+                if (fd6 >= 0) {
+                    close(fd6);
+                    fd6 = -1;
+                    ai_fam = AF_INET;
+                }
+                break;
+            case AF_INET6:
+                if (fd4 >= 0) {
+                    close(fd4);
+                    fd4 = -1;
+                    ai_fam = AF_INET6;
+                }
+                break;
+#endif
+            case AF_UNSPEC:
+                break;
+            default:
                 syslog(LOG_ERR,
                        "Numeric IPv6 addresses need to be enclosed in []");
                 exit(EX_USAGE);
@@ -556,8 +588,8 @@ int main(int argc, char **argv)
                                         (union sock_addr *)&bindaddr4, NULL);
                     if (err) {
                         syslog(LOG_ERR,
-                               "cannot resolve local IPv4 bind address: %s",
+                               "cannot resolve local IPv4 bind address: %s, %s",
-                               address);
+                               address, gai_strerror(err));
                         exit(EX_NOINPUT);
                     }
                 }
@@ -570,13 +602,14 @@ int main(int argc, char **argv)
                         if (fd4 >= 0) {
                             syslog(LOG_ERR,
                                    "cannot resolve local IPv6 bind address: %s"
-                                   "; using IPv4 only", address);
+                                   "(%s); using IPv4 only",
+                                   address, gai_strerror(err));
                             close(fd6);
                             fd6 = -1;
                         } else {
                             syslog(LOG_ERR,
-                                   "cannot resolve local IPv6 bind address: %s",
+                                   "cannot resolve local IPv6 bind address: %s"
-                                   address);
+                                   "(%s)", address, gai_strerror(err));
                             exit(EX_NOINPUT);
                         }
                     }