From b528aaef035213dee93663599dc46b1898ae3f8e Mon Sep 17 00:00:00 2001
From: Nick Mathewson <nickm@torproject.org>
Date: Fri, 1 Mar 2013 12:22:57 -0500
Subject: [PATCH 1/2] Make sure that [::1] is recognized as a private address

Fixes bug 8377; bugfix on 0.2.1.3-alpha.
---
 changes/bug8377      | 3 +++
 src/common/address.c | 3 ++-
 2 files changed, 5 insertions(+), 1 deletion(-)
 create mode 100644 changes/bug8377

diff --git a/changes/bug8377 b/changes/bug8377
new file mode 100644
index 0000000000..c9ad151bc9
--- /dev/null
+++ b/changes/bug8377
@@ -0,0 +1,3 @@
+  o Minor bugfixes:
+    - Correctly recognize that [::1] is a loopback address. Fixes bug #8377;
+      bugfix on 0.2.1.3-alpha.
diff --git a/src/common/address.c b/src/common/address.c
index e88869f1d8..df26f61f8f 100644
--- a/src/common/address.c
+++ b/src/common/address.c
@@ -779,7 +779,8 @@ tor_addr_is_loopback(const tor_addr_t *addr)
     case AF_INET6: {
       /* ::1 */
       uint32_t *a32 = tor_addr_to_in6_addr32(addr);
-      return (a32[0] == 0) && (a32[1] == 0) && (a32[2] == 0) && (a32[3] == 1);
+      return (a32[0] == 0) && (a32[1] == 0) && (a32[2] == 0) &&
+        (ntohl(a32[3]) == 1);
     }
     case AF_INET:
       /* 127.0.0.1 */

From 165b2c0123f0ffb1f9507aaa31cdd536b91bccdf Mon Sep 17 00:00:00 2001
From: Nick Mathewson <nickm@torproject.org>
Date: Fri, 1 Mar 2013 12:40:41 -0500
Subject: [PATCH 2/2] Add unit test for tor_addr_is_loopback

---
 src/test/test_addr.c | 36 ++++++++++++++++++++++++++++++++++++
 1 file changed, 36 insertions(+)

diff --git a/src/test/test_addr.c b/src/test/test_addr.c
index 9007a23c5c..e3f38073ec 100644
--- a/src/test/test_addr.c
+++ b/src/test/test_addr.c
@@ -623,12 +623,48 @@ test_addr_ip6_helpers(void)
   ;
 }
 
+static void
+test_addr_is_loopback(void *data)
+{
+  static const struct loopback_item {
+    const char *name;
+    int is_loopback;
+  } loopback_items[] = {
+    { "::1", 1 },
+    { "127.0.0.1", 1 },
+    { "127.99.100.101", 1 },
+    { "128.99.100.101", 0 },
+    { "8.8.8.8", 0 },
+    { "0.0.0.0", 0 },
+    { "::2", 0 },
+    { "::", 0 },
+    { "::1.0.0.0", 0 },
+    { NULL, 0 }
+  };
+
+  int i;
+  tor_addr_t addr;
+  (void)data;
+
+  for (i=0; loopback_items[i].name; ++i) {
+    tt_int_op(tor_addr_parse(&addr, loopback_items[i].name), >=, 0);
+    tt_int_op(tor_addr_is_loopback(&addr), ==, loopback_items[i].is_loopback);
+  }
+
+  tor_addr_make_unspec(&addr);
+  tt_int_op(tor_addr_is_loopback(&addr), ==, 0);
+
+ done:
+  ;
+}
+
 #define ADDR_LEGACY(name)                                               \
   { #name, legacy_test_helper, 0, &legacy_setup, test_addr_ ## name }
 
 struct testcase_t addr_tests[] = {
   ADDR_LEGACY(basic),
   ADDR_LEGACY(ip6_helpers),
+  { "is_loopback", test_addr_is_loopback, 0, NULL, NULL },
   END_OF_TESTCASES
 };