Stub out getaddrinfo() and freeaddrinfo().

We may not be able have access to DNS in the fuzzing environment.

1 files changed, 64 insertions, 0 deletions

diff --git a/logsrvd/regress/fuzz/fuzz_logsrvd_conf.c b/logsrvd/regress/fuzz/fuzz_logsrvd_conf.c
index 39cd66399..cd578d16f 100644
--- a/logsrvd/regress/fuzz/fuzz_logsrvd_conf.c
+++ b/logsrvd/regress/fuzz/fuzz_logsrvd_conf.c
@@ -65,6 +65,70 @@ sudo_regex_compile_v1(void *v, const char *pattern, const char **errstr)
     return true;
 }
 
+/*
+ * The fuzzing environment may not have DNS available, this may result
+ * in long delays that cause a timeout when fuzzing.  This getaddrinfo()
+ * can look up "localhost" and returns an error for anything else.
+ */
+#ifdef FUZZING_BUILD_MODE_UNSAFE_FOR_PRODUCTION
+/* Avoid compilation errors if getaddrinfo() or freeaddrinfo() are macros. */
+# undef getaddrinfo
+# undef freeaddrinfo
+
+int
+# ifdef HAVE_GETADDRINFO
+getaddrinfo(
+# else
+sudo_getaddrinfo(
+# endif
+    const char *nodename, const char *servname,
+    const struct addrinfo *hints, struct addrinfo **res)
+{
+    struct addrinfo *ai;
+    struct in_addr addr;
+
+    /* Stub getaddrinfo(3) to avoid a DNS timeout in CIfuzz. */
+    if (strcmp(nodename, "localhost") != 0 || servname != NULL)
+	return EAI_FAIL;
+
+    /* Hard-code localhost. */
+    ai = calloc(1, sizeof(*ai) + sizeof(struct sockaddr_in));
+    if (ai == NULL)
+	return EAI_MEMORY;
+    ai->ai_canonname = strdup("localhost");
+    if (ai == NULL) {
+	free(ai);
+	return EAI_MEMORY;
+    }
+    ai->ai_family = AF_INET;
+    ai->ai_protocol = IPPROTO_TCP;
+    ai->ai_addrlen = sizeof(struct sockaddr_in);
+    ai->ai_addr = (struct sockaddr *)(ai + 1);
+    inet_pton(AF_INET, "127.0.0.1", &addr);
+    ((struct sockaddr_in *)ai->ai_addr)->sin_family = AF_INET;
+    ((struct sockaddr_in *)ai->ai_addr)->sin_addr = addr;
+    *res = ai;
+    return 0;
+}
+
+void
+# ifdef HAVE_GETADDRINFO
+freeaddrinfo(struct addrinfo *ai)
+# else
+sudo_freeaddrinfo(struct addrinfo *ai)
+# endif
+{
+    struct addrinfo *next;
+
+    while (ai != NULL) {
+	next = ai->ai_next;
+	free(ai->ai_canonname);
+	free(ai);
+	ai = next;
+    }
+}
+#endif /* FUZZING_BUILD_MODE_UNSAFE_FOR_PRODUCTION */
+
 static int
 fuzz_conversation(int num_msgs, const struct sudo_conv_message msgs[],
     struct sudo_conv_reply replies[], struct sudo_conv_callback *callback)