[pseudo][PATCH 07/11] test: Add test cases for canonicalize functions

From: Mark Hatle <[email protected]>

Verify canonicalize, which calls realpath, both in a normal and
emulated chroot environment.

AI-Generated: test cases generated by github copilot (claude opus 6.4)

Signed-off-by: Mark Hatle <[email protected]>
Signed-off-by: Mark Hatle <[email protected]>
---
 test/test-canonicalize.c  | 171 ++++++++++++++++++++++++++++++++++++++++++++++
 test/test-canonicalize.sh |  11 +++
 2 files changed, 182 insertions(+)
 create mode 100644 test/test-canonicalize.c
 create mode 100755 test/test-canonicalize.sh

diff --git a/test/test-canonicalize.c b/test/test-canonicalize.c
new file mode 100644
index 0000000..db20f25
--- /dev/null
+++ b/test/test-canonicalize.c
@@ -0,0 +1,171 @@
+/*
+ * Test canonicalize_file_name
+ * SPDX-License-Identifier: LGPL-2.1-only
+ */
+#define _GNU_SOURCE
+
+#include <sys/types.h>
+#include <sys/stat.h>
+#include <fcntl.h>
+#include <stdio.h>
+#include <stdlib.h>
+#include <unistd.h>
+#include <string.h>
+#include <limits.h>
+
+static int failures = 0;
+
+static void check(const char *desc, int condition) {
+    if (!condition) {
+        fprintf(stderr, "FAIL: %s\n", desc);
+        failures++;
+    }
+}
+
+static int test_basic(void) {
+    char *result;
+    char cwd[PATH_MAX];
+    int fd;
+
+    if (!getcwd(cwd, sizeof(cwd))) {
+        perror("getcwd");
+        return 1;
+    }
+
+    /* Create a test file and symlink */
+    fd = open("test_canon_file", O_CREAT | O_WRONLY, 0644);
+    close(fd);
+    if (symlink("test_canon_file", "test_canon_link") != 0) {
+        perror("symlink");
+        return 1;
+    }
+
+    /* canonicalize_file_name on regular file */
+    result = canonicalize_file_name("test_canon_file");
+    check("canon file", result != NULL);
+    if (result) {
+        check("canon file starts with /", result[0] == '/');
+        check("canon file contains name", strstr(result, "test_canon_file") != NULL);
+        free(result);
+    }
+
+    /* canonicalize_file_name on symlink (should resolve) */
+    result = canonicalize_file_name("test_canon_link");
+    check("canon link", result != NULL);
+    if (result) {
+        check("canon link resolves", strstr(result, "test_canon_file") != NULL);
+        /* Should NOT contain the link name */
+        check("canon link not link", strstr(result, "test_canon_link") == NULL);
+        free(result);
+    }
+
+    /* canonicalize_file_name on . */
+    result = canonicalize_file_name(".");
+    check("canon dot", result != NULL);
+    if (result) {
+        check("canon dot matches cwd", strcmp(result, cwd) == 0);
+        free(result);
+    }
+
+    /* canonicalize_file_name on nonexistent should return NULL */
+    result = canonicalize_file_name("test_canon_noexist");
+    check("canon noexist NULL", result == NULL);
+
+    unlink("test_canon_link");
+    unlink("test_canon_file");
+
+    return 0;
+}
+
+static int test_chroot(const char *chroot_dir) {
+    char *result;
+    char path[PATH_MAX];
+    int fd;
+
+    /* Create test file and symlink inside the chroot directory */
+    snprintf(path, sizeof(path), "%s/cr_canon_file", chroot_dir);
+    fd = open(path, O_CREAT | O_WRONLY, 0644);
+    if (fd < 0) { perror("open chroot file"); return 1; }
+    close(fd);
+
+    snprintf(path, sizeof(path), "%s/cr_canon_link", chroot_dir);
+    if (symlink("cr_canon_file", path) != 0) {
+        perror("symlink in chroot dir");
+        return 1;
+    }
+
+    /* Also create an absolute-target symlink */
+    snprintf(path, sizeof(path), "%s/cr_abs_link", chroot_dir);
+    if (symlink("/cr_canon_file", path) != 0) {
+        perror("abs symlink in chroot dir");
+        return 1;
+    }
+
+    if (chroot(chroot_dir) != 0) {
+        perror("chroot");
+        return 1;
+    }
+    if (chdir("/") != 0) {
+        perror("chdir /");
+        return 1;
+    }
+
+    /* canonicalize on a file: result must be /cr_canon_file, not
+     * /real/path/to/chroot/cr_canon_file */
+    result = canonicalize_file_name("/cr_canon_file");
+    check("chroot: canon abs file", result != NULL);
+    if (result) {
+        check("chroot: canon abs file path", strcmp(result, "/cr_canon_file") == 0);
+        free(result);
+    }
+
+    /* canonicalize on a relative symlink */
+    result = canonicalize_file_name("/cr_canon_link");
+    check("chroot: canon rel symlink", result != NULL);
+    if (result) {
+        check("chroot: canon rel symlink resolves", strcmp(result, "/cr_canon_file") == 0);
+        free(result);
+    }
+
+    /* canonicalize on an absolute-target symlink */
+    result = canonicalize_file_name("/cr_abs_link");
+    check("chroot: canon abs symlink", result != NULL);
+    if (result) {
+        check("chroot: canon abs symlink resolves", strcmp(result, "/cr_canon_file") == 0);
+        free(result);
+    }
+
+    /* canonicalize on . should return / */
+    result = canonicalize_file_name(".");
+    check("chroot: canon dot", result != NULL);
+    if (result) {
+        check("chroot: canon dot is /", strcmp(result, "/") == 0);
+        free(result);
+    }
+
+    /* path traversal: /../cr_canon_file must stay confined */
+    result = canonicalize_file_name("/../cr_canon_file");
+    check("chroot: canon traverse", result != NULL);
+    if (result) {
+        check("chroot: canon traverse resolves", strcmp(result, "/cr_canon_file") == 0);
+        free(result);
+    }
+
+    return 0;
+}
+
+int main(int argc, char *argv[]) {
+    int rc;
+
+    rc = test_basic();
+    if (rc)
+        return rc;
+
+    if (argc > 1) {
+        rc = test_chroot(argv[1]);
+        if (rc)
+            return rc;
+    }
+
+    return failures;
+}
diff --git a/test/test-canonicalize.sh b/test/test-canonicalize.sh
new file mode 100755
index 0000000..4a1c321
--- /dev/null
+++ b/test/test-canonicalize.sh
@@ -0,0 +1,11 @@
+#!/bin/bash
+#
+# SPDX-License-Identifier: LGPL-2.1-only
+#
+# Test canonicalize_file_name (basic + chroot)
+
+CHROOT_DIR=$(mktemp -d "${PWD}/chroot_canon_XXXXXX")
+trap "rm -rf '$CHROOT_DIR'" 0
+
+rm -f test_canon_file test_canon_link
+./test/test-canonicalize "$CHROOT_DIR"
-- 
1.8.3.1