Improve buffer handling in Windows sk_getaddr() -- we were passing

[u/mdw/putty] / windows / winnet.c

diff --git a/windows/winnet.c b/windows/winnet.c
index db5f54e..9d93baa 100644 (file)
--- a/windows/winnet.c
+++ b/windows/winnet.c
@@ -429,10 +429,8 @@ SockAddr sk_namelookup(const char *host, char **canonicalname,
 {
     SockAddr ret = snew(struct SockAddr_tag);
     unsigned long a;
-    struct hostent *h = NULL;
     char realhost[8192];
     int hint_family;
-    int err;
 
     /* Default to IPv4. */
     hint_family = (address_family == ADDRTYPE_IPV4 ? AF_INET :
@@ -452,6 +450,8 @@ SockAddr sk_namelookup(const char *host, char **canonicalname,
     *realhost = '\0';
 
     if ((a = p_inet_addr(host)) == (unsigned long) INADDR_NONE) {
+       struct hostent *h = NULL;
+       int err;
 #ifndef NO_IPV6
        /*
         * Use getaddrinfo when it's available
@@ -584,11 +584,19 @@ void sk_getaddr(SockAddr addr, char *buf, int buflen)
 
 #ifndef NO_IPV6
     if (step.ai) {
+       int err = 0;
        if (p_WSAAddressToStringA) {
-           p_WSAAddressToStringA(step.ai->ai_addr, step.ai->ai_addrlen,
-                                 NULL, buf, &buflen);
+           DWORD dwbuflen = buflen;
+           err = p_WSAAddressToStringA(step.ai->ai_addr, step.ai->ai_addrlen,
+                                       NULL, buf, &dwbuflen);
        } else
-           strncpy(buf, "IPv6", buflen);
+           err = -1;
+       if (err) {
+           strncpy(buf, addr->hostname, buflen);
+           if (!buf[0])
+               strncpy(buf, "<unknown>", buflen);
+           buf[buflen-1] = '\0';
+       }
     } else
 #endif
     if (SOCKADDR_FAMILY(addr, step) == AF_INET) {