Fix getaddrinfo with protocol unset on Solaris 9. Found by Dagobert Michelsen

Apparently when you call Solaris 9's getaddrinfo(), it likes to leave
ai_protocol unset in the result. This is no way to behave, if I'm
reading RFC3493 right.

This patch makes us check for a getaddrinfo() that's broken in this way,
and work around it by trying to infer socktype and protocol from one
another.

Partial bugfix for 2987542

diff --git a/evutil.c b/evutil.c
index af5b069aa1626905e5239f6301909055760f0587..5fc90a8637225818758452f8be15ed9c8c991a1f 100644 (file)
--- a/evutil.c
+++ b/evutil.c
@@ -959,6 +959,10 @@ evutil_adjust_hints_for_addrconfig(struct evutil_addrinfo *hints)
 }
 
 #ifdef USE_NATIVE_GETADDRINFO
+static int need_numeric_port_hack_=0;
+static int need_socktype_protocol_hack_=0;
+static int tested_for_getaddrinfo_hacks=0;
+
 /* Some older BSDs (like OpenBSD up to 4.6) used to believe that
    giving a numeric port without giving an ai_socktype was verboten.
    We test for this so we can apply an appropriate workaround.  If it
@@ -973,17 +977,17 @@ evutil_adjust_hints_for_addrconfig(struct evutil_addrinfo *hints)
 
    We test for this bug at runtime, since otherwise we can't have the
    same binary run on multiple BSD versions.
+
+   - Some versions of Solaris believe that it's nice to leave to protocol
+     field set to 0.  We test for this so we can apply an appropriate
+     workaround.
 */
-static int
-need_numeric_port_hack(void)
+static void
+test_for_getaddrinfo_hacks(void)
 {
-       static int tested=0;
-       static int need_hack=0;
        int r, r2;
        struct evutil_addrinfo *ai=NULL, *ai2=NULL;
        struct evutil_addrinfo hints;
-       if (tested)
-               return need_hack;
 
        memset(&hints,0,sizeof(hints));
        hints.ai_family = PF_UNSPEC;
@@ -999,21 +1003,40 @@ need_numeric_port_hack(void)
        hints.ai_socktype = SOCK_STREAM;
        r2 = getaddrinfo("1.2.3.4", "80", &hints, &ai2);
        if (r2 == 0 && r != 0) {
-               need_hack=1;
+               need_numeric_port_hack_=1;
        }
+       if (ai2 && ai2->ai_protocol == 0) {
+               need_socktype_protocol_hack_=1;
+       }
+
        if (ai)
                freeaddrinfo(ai);
        if (ai2)
                freeaddrinfo(ai2);
-       tested = 1;
-       return need_hack;
+       tested_for_getaddrinfo_hacks=1;
+}
+
+static inline int
+need_numeric_port_hack(void)
+{
+       if (!tested_for_getaddrinfo_hacks)
+               test_for_getaddrinfo_hacks();
+       return need_numeric_port_hack_;
+}
+
+static inline int
+need_socktype_protocol_hack(void)
+{
+       if (!tested_for_getaddrinfo_hacks)
+               test_for_getaddrinfo_hacks();
+       return need_socktype_protocol_hack_;
 }
 
 static void
 apply_numeric_port_hack(int port, struct evutil_addrinfo **ai)
 {
        /* Now we run through the list and set the ports on all of the
-        * results where ports */
+        * results where ports would make sense. */
        for ( ; *ai; ai = &(*ai)->ai_next) {
                struct sockaddr *sa = (*ai)->ai_addr;
                if (sa && sa->sa_family == AF_INET) {
@@ -1100,6 +1123,10 @@ evutil_getaddrinfo(const char *nodename, const char *servname,
                servname = NULL;
        }
 
+       if (need_socktype_protocol_hack()) {
+               evutil_getaddrinfo_infer_protocols(&hints);
+       }
+
        /* Make sure that we didn't actually steal any AI_FLAGS values that
         * the system is using.  (This is a constant expression, and should ge
         * optimized out.)
@@ -1115,6 +1142,12 @@ evutil_getaddrinfo(const char *nodename, const char *servname,
        err = getaddrinfo(nodename, servname, &hints, res);
        if (need_np_hack)
                apply_numeric_port_hack(portnum, res);
+
+       if (need_socktype_protocol_hack()) {
+               struct evutil_addrinfo *ai;
+               for (ai = *res; ai; ai = ai->ai_next)
+                       evutil_getaddrinfo_infer_protocols(ai);
+       } 
        return err;
 #else
        int port=0, err;