Bug 1769295 - selfserv and tstclnt should use PR_GetPrefLoopbackAddrInfo. r=rrelyea

Differential Revision: https://phabricator.services.mozilla.com/D146334

4 files changed, 181 insertions, 31 deletions

diff --git a/automation/abi-check/expected-report-libnspr4.so.txt b/automation/abi-check/expected-report-libnspr4.so.txt
index e69de29bb..b8b5c57b2 100644
--- a/automation/abi-check/expected-report-libnspr4.so.txt
+++ b/automation/abi-check/expected-report-libnspr4.so.txt
@@ -0,0 +1,5 @@
+
+1 Added function:
+
+  'function PRStatus PR_GetPrefLoopbackAddrInfo(PRNetAddr*, PRUint16)'    {PR_GetPrefLoopbackAddrInfo}
+
diff --git a/cmd/selfserv/selfserv.c b/cmd/selfserv/selfserv.c
index 5094cc7bf..d26851d98 100644
--- a/cmd/selfserv/selfserv.c
+++ b/cmd/selfserv/selfserv.c
@@ -1711,19 +1711,30 @@ do_accepts(
 PRFileDesc *
 getBoundListenSocket(unsigned short port)
 {
-    PRFileDesc *listen_sock;
+    PRFileDesc *listen_sock = NULL;
     int listenQueueDepth = 5 + (2 * maxThreads);
     PRStatus prStatus;
     PRNetAddr addr;
     PRSocketOptionData opt;
 
-    addr.inet.family = PR_AF_INET;
-    addr.inet.ip = PR_INADDR_ANY;
-    addr.inet.port = PR_htons(port);
+    // We want to listen on the IP family that tstclnt will use.
+    // tstclnt uses PR_GetPrefLoopbackAddrInfo to decide, if it's
+    // asked to connect to localhost.
+
+    prStatus = PR_GetPrefLoopbackAddrInfo(&addr, port);
+    if (prStatus == PR_FAILURE) {
+        addr.inet.family = PR_AF_INET;
+        addr.inet.ip = PR_INADDR_ANY;
+        addr.inet.port = PR_htons(port);
+    }
 
-    listen_sock = PR_NewTCPSocket();
+    if (addr.inet.family == PR_AF_INET6) {
+        listen_sock = PR_OpenTCPSocket(PR_AF_INET6);
+    } else if (addr.inet.family == PR_AF_INET) {
+        listen_sock = PR_NewTCPSocket();
+    }
     if (listen_sock == NULL) {
-        errExit("PR_NewTCPSocket");
+        errExit("Couldn't create socket");
     }
 
     opt.option = PR_SockOpt_Nonblocking;
diff --git a/cmd/tstclnt/tstclnt.c b/cmd/tstclnt/tstclnt.c
index 6d3359c03..453842b16 100644
--- a/cmd/tstclnt/tstclnt.c
+++ b/cmd/tstclnt/tstclnt.c
@@ -2190,32 +2190,45 @@ main(int argc, char **argv)
     if (status == PR_SUCCESS) {
         addr.inet.port = PR_htons(portno);
     } else {
-        /* Lookup host */
-        PRAddrInfo *addrInfo;
-        void *enumPtr = NULL;
-
-        addrInfo = PR_GetAddrInfoByName(host, PR_AF_UNSPEC,
-                                        PR_AI_ADDRCONFIG | PR_AI_NOCANONNAME);
-        if (!addrInfo) {
-            fprintf(stderr, "HOSTNAME=%s\n", host);
-            SECU_PrintError(progName, "error looking up host");
-            error = 1;
-            goto done;
-        }
-        for (;;) {
-            enumPtr = PR_EnumerateAddrInfo(enumPtr, addrInfo, portno, &addr);
-            if (enumPtr == NULL)
-                break;
-            if (addr.raw.family == PR_AF_INET && allowIPv4)
-                break;
-            if (addr.raw.family == PR_AF_INET6 && allowIPv6)
-                break;
+        PRBool gotLoopbackIP = PR_FALSE;
+        if ((!strcmp(host, "localhost") || !strcmp(host, "localhost.localdomain"))
+            /* only check for preference if both types are allowed */
+            && allowIPv4 && allowIPv6) {
+            /* make a decision which IP to prefer */
+            status = PR_GetPrefLoopbackAddrInfo(&addr, portno);
+            if (status != PR_FAILURE) {
+                gotLoopbackIP = PR_TRUE;
+            }
         }
-        PR_FreeAddrInfo(addrInfo);
-        if (enumPtr == NULL) {
-            SECU_PrintError(progName, "error looking up host address");
-            error = 1;
-            goto done;
+
+        if (!gotLoopbackIP) {
+            /* Lookup host */
+            PRAddrInfo *addrInfo;
+            void *enumPtr = NULL;
+
+            addrInfo = PR_GetAddrInfoByName(host, PR_AF_UNSPEC,
+                                            PR_AI_ADDRCONFIG | PR_AI_NOCANONNAME);
+            if (!addrInfo) {
+                fprintf(stderr, "HOSTNAME=%s\n", host);
+                SECU_PrintError(progName, "error looking up host");
+                error = 1;
+                goto done;
+            }
+            for (;;) {
+                enumPtr = PR_EnumerateAddrInfo(enumPtr, addrInfo, portno, &addr);
+                if (enumPtr == NULL)
+                    break;
+                if (addr.raw.family == PR_AF_INET && allowIPv4)
+                    break;
+                if (addr.raw.family == PR_AF_INET6 && allowIPv6)
+                    break;
+            }
+            PR_FreeAddrInfo(addrInfo);
+            if (enumPtr == NULL) {
+                SECU_PrintError(progName, "error looking up host address");
+                error = 1;
+                goto done;
+            }
         }
     }
 
diff --git a/nspr.patch b/nspr.patch
new file mode 100644
index 000000000..4300489e1
--- /dev/null
+++ b/nspr.patch
@@ -0,0 +1,121 @@
+# HG changeset patch
+# User Kai Engert <kaie@kuix.de>
+# Date 1652465540 -7200
+#      Fri May 13 20:12:20 2022 +0200
+# Node ID 2be45a781ba18e5904c1eed4dc0e1d66248d303c
+# Parent  005070e9849523de6c647dd15dd8a709db0f3b7d
+Bug 1769293 - Add API PR_GetPrefLoopbackAddrInfo. r=rrelyea
+
+Differential Revision: https://phabricator.services.mozilla.com/D146333
+
+diff --git a/pr/include/prnetdb.h b/pr/include/prnetdb.h
+--- a/pr/include/prnetdb.h
++++ b/pr/include/prnetdb.h
+@@ -426,10 +426,13 @@ NSPR_API(void) PR_FreeAddrInfo(PRAddrInf
+ **                      is ended if this value is NULL.
+ ***********************************************************************/
+ NSPR_API(void *) PR_EnumerateAddrInfo(
+     void *enumPtr, const PRAddrInfo *addrInfo, PRUint16 port, PRNetAddr *result);
+ 
++NSPR_API(PRStatus) PR_GetPrefLoopbackAddrInfo(PRNetAddr *result,
++                                              PRUint16 port);
++
+ /***********************************************************************
+ ** FUNCTION:
+ ** DESCRIPTION: PR_GetCanonNameFromAddrInfo()
+ **  Extracts the canonical name of the hostname passed to
+ **  PR_GetAddrInfoByName().
+diff --git a/pr/src/misc/prnetdb.c b/pr/src/misc/prnetdb.c
+--- a/pr/src/misc/prnetdb.c
++++ b/pr/src/misc/prnetdb.c
+@@ -2176,10 +2176,77 @@ PR_IMPLEMENT(PRAddrInfo *) PR_GetAddrInf
+     }
+     return NULL;
+ #endif
+ }
+ 
++PR_IMPLEMENT(PRStatus)
++PR_GetPrefLoopbackAddrInfo(PRNetAddr *result,
++                           PRUint16 port)
++{
++    char          tmpBuf[ 40 ];
++    const int     tmpBufSize = sizeof( tmpBuf );
++
++    if (!result) {
++        PR_SetError(PR_INVALID_ARGUMENT_ERROR, 0);
++        return PR_FAILURE;
++    }
++
++    if (!_pr_initialized) _PR_ImplicitInitialization();
++
++    PR_snprintf(tmpBuf, tmpBufSize, "%u", port );
++
++#if !defined(_PR_HAVE_GETADDRINFO) || !defined(AI_PASSIVE)
++    PR_SetError(PR_NOT_IMPLEMENTED_ERROR, 0);
++    return PR_FAILURE;
++#else
++
++    PRADDRINFO *res, hints;
++    PRStatus rv;
++
++    memset(&hints, 0, sizeof(hints));
++
++    rv = GETADDRINFO(NULL, tmpBuf, &hints, &res);
++    if (rv == 0) {
++        PRBool result_still_empty = PR_TRUE;
++        PRADDRINFO *ai = res;
++        do {
++            PRNetAddr aNetAddr;
++
++            while (ai && ai->ai_addrlen > sizeof(PRNetAddr))
++                ai = ai->ai_next;
++
++            if (ai) {
++                /* copy sockaddr to PRNetAddr */
++                memcpy(&aNetAddr, ai->ai_addr, ai->ai_addrlen);
++                aNetAddr.raw.family = ai->ai_addr->sa_family;
++#ifdef _PR_INET6
++                if (AF_INET6 == aNetAddr.raw.family)
++                    aNetAddr.raw.family = PR_AF_INET6;
++#endif
++                if (ai->ai_addrlen < sizeof(PRNetAddr))
++                    memset(((char*)result)+ai->ai_addrlen, 0,
++                           sizeof(PRNetAddr) - ai->ai_addrlen);
++            }
++
++            /* If we obtain more than one result, prefer IPv6. */
++            if (result_still_empty || aNetAddr.raw.family == PR_AF_INET6) {
++                memcpy(result, &aNetAddr, sizeof(PRNetAddr));
++            }
++            result_still_empty = PR_FALSE;
++            ai = ai->ai_next;
++        }
++        while (ai);
++
++        FREEADDRINFO(res);
++        return PR_SUCCESS;
++    }
++
++    PR_SetError(PR_DIRECTORY_LOOKUP_ERROR, rv);
++    return PR_FAILURE;
++#endif
++}
++
+ PR_IMPLEMENT(void) PR_FreeAddrInfo(PRAddrInfo *ai)
+ {
+ #if defined(_PR_HAVE_GETADDRINFO)
+ #if defined(_PR_INET6_PROBE)
+     if (!_pr_ipv6_is_present()) {
+diff --git a/pr/src/nspr.def b/pr/src/nspr.def
+--- a/pr/src/nspr.def
++++ b/pr/src/nspr.def
+@@ -460,5 +460,9 @@ EXPORTS ;-
+ ;+NSPR_4.12 {
+ ;+      global:
+ 		PR_DuplicateEnvironment;
+ 		PR_GetEnvSecure;
+ ;+} NSPR_4.10.3;
++;+NSPR_4.34 {
++;+      global:
++    PR_GetPrefLoopbackAddrInfo;
++;+} NSPR_4.12;