Add OSS-Fuzz Zeek script search path to fuzzers

src/fuzzers/fuzzer-setup.h

@@ -1,5 +1,6 @@
 #pragma once
 
+#include <unistd.h>
 #include <cstdlib>
 
 #include "zeek-setup.h"
@@ -11,6 +12,22 @@
 
 extern "C" int LLVMFuzzerInitialize(int* argc, char*** argv)
 	{
+	auto zeekpath = getenv("ZEEKPATH");
+
+	if ( ! zeekpath )
+		{
+		// Set up an expected script search path for use with OSS-Fuzz
+		auto constexpr oss_fuzz_scripts = "oss-fuzz-zeek-scripts";
+		auto fuzzer_path = get_exe_path(*argv[0]);
+		auto fuzzer_dir = SafeDirname(fuzzer_path).result;
+		std::string fs = fmt("%s/%s", fuzzer_dir.data(), oss_fuzz_scripts);
+		auto p = fs.data();
+		auto oss_fuzz_zeekpath = fmt(".:%s:%s/policy:%s/site", p, p, p);
+
+		if ( setenv("ZEEKPATH", oss_fuzz_zeekpath, true) == -1 )
+			abort();
+		}
+
 	zeek::Options options;
 	options.scripts_to_load.emplace_back("local.zeek");
 	options.script_options_to_set.emplace_back("Site::local_nets={10.0.0.0/8}");

src/util.cc

@@ -1745,6 +1745,38 @@ static string find_file_in_path(const string& filename, const string& path,
 	return string();
 	}
 
+std::string get_exe_path(const std::string& invocation)
+	{
+	if ( invocation.empty() )
+		return "";
+
+	if ( invocation[0] == '/' || invocation[0] == '~' )
+		// Absolute path
+		return invocation;
+
+	if ( invocation.find('/') != std::string::npos )
+		{
+		// Relative path
+		char cwd[PATH_MAX];
+
+		if ( ! getcwd(cwd, sizeof(cwd)) )
+			{
+			fprintf(stderr, "failed to get current directory: %s\n",
+			        strerror(errno));
+			exit(1);
+			}
+
+		return std::string(cwd) + "/" + invocation;
+		}
+
+	auto path = getenv("PATH");
+
+	if ( ! path )
+		return "";
+
+	return find_file(invocation, path);
+	}
+
 string find_file(const string& filename, const string& path_set,
                  const string& opt_ext)
 	{

src/util.h

@@ -346,6 +346,14 @@ std::string normalize_path(std::string_view path);
  */
 std::string without_bropath_component(std::string_view path);
 
+/**
+ * Gets the full path used to invoke some executable.
+ * @param invocation  any possible string that may be seen in argv[0], such as
+ *                    absolute path, relative path, or name to lookup in PATH.
+ * @return the absolute path to the executable file
+ */
+std::string get_exe_path(const std::string& invocation);
+
 /**
  * Locate a file within a given search path.
  * @param filename Name of a file to find.

src/zeek-setup.cc

@@ -374,38 +374,6 @@ static std::vector<std::string> get_script_signature_files()
 	return rval;
 	}
 
-static std::string get_exe_path(const std::string& invocation)
-	{
-	if ( invocation.empty() )
-		return "";
-
-	if ( invocation[0] == '/' || invocation[0] == '~' )
-		// Absolute path
-		return invocation;
-
-	if ( invocation.find('/') != std::string::npos )
-		{
-		// Relative path
-		char cwd[PATH_MAX];
-
-		if ( ! getcwd(cwd, sizeof(cwd)) )
-			{
-			fprintf(stderr, "failed to get current directory: %s\n",
-			        strerror(errno));
-			exit(1);
-			}
-
-		return std::string(cwd) + "/" + invocation;
-		}
-
-	auto path = getenv("PATH");
-
-	if ( ! path )
-		return "";
-
-	return find_file(invocation, path);
-	}
-
 zeek::SetupResult zeek::setup(int argc, char** argv, zeek::Options* zopts)
 	{
 	ZEEK_LSAN_DISABLE();