On Fri, Feb 21, 2025 at 4:41 AM Rahul Sandhu <nvraxn@xxxxxxxxx> wrote:
>
> Passing a const char * to basename(3) is a glibc-specific extension, so
> create our own basename implementation. As it's a trivial 2 LOC, always
> use our implementation of basename even if glibc is available to avoid
> the complications of attaining the non-posix glibc implementation of
> basename(3) as _GNU_SOURCE needs to be defined, but libgen.h also needs
> to have not been included.
>
> Also fix a missing check for selinux_policy_root(3). From the man page:
> On failure, selinux_policy_root returns NULL.
>
> As the glibc basename(3) (unlike posix basename(3)) does not support
> having a nullptr passed to it, only pass the policy_root to basename(3)
> if it is non-null.
>
> Signed-off-by: Rahul Sandhu <nvraxn@xxxxxxxxx>
Acked-by: James Carter <jwcart2@xxxxxxxxx>
> ---
> libsemanage/src/conf-parse.y | 13 ++++++++++---
> libsemanage/src/direct_api.c | 1 +
> libsemanage/src/utilities.c | 9 +++++++++
> libsemanage/src/utilities.h | 13 +++++++++++++
> libsemanage/tests/test_utilities.c | 26 ++++++++++++++++++++++++++
> 5 files changed, 59 insertions(+), 3 deletions(-)
>
> diff --git a/libsemanage/src/conf-parse.y b/libsemanage/src/conf-parse.y
> index 6cb8a598..d3ca5f1f 100644
> --- a/libsemanage/src/conf-parse.y
> +++ b/libsemanage/src/conf-parse.y
> @@ -21,6 +21,7 @@
> %{
>
> #include "semanage_conf.h"
> +#include "utilities.h"
>
> #include <sepol/policydb.h>
> #include <selinux/selinux.h>
> @@ -382,7 +383,10 @@ external_opt: PROG_PATH '=' ARG { PASSIGN(new_external->path, $3); }
> static int semanage_conf_init(semanage_conf_t * conf)
> {
> conf->store_type = SEMANAGE_CON_DIRECT;
> - conf->store_path = strdup(basename(selinux_policy_root()));
> + const char *policy_root = selinux_policy_root();
> + if (policy_root != NULL) {
> + conf->store_path = strdup(semanage_basename(policy_root));
> + }
> conf->ignoredirs = NULL;
> conf->store_root_path = strdup("/var/lib/selinux");
> conf->compiler_directory_path = strdup("/usr/libexec/selinux/hll");
> @@ -544,8 +548,11 @@ static int parse_module_store(char *arg)
> free(current_conf->store_path);
> if (strcmp(arg, "direct") == 0) {
> current_conf->store_type = SEMANAGE_CON_DIRECT;
> - current_conf->store_path =
> - strdup(basename(selinux_policy_root()));
> + const char *policy_root = selinux_policy_root();
> + if (policy_root != NULL) {
> + current_conf->store_path =
> + strdup(semanage_basename(policy_root));
> + }
> current_conf->server_port = -1;
> } else if (*arg == '/') {
> current_conf->store_type = SEMANAGE_CON_POLSERV_LOCAL;
> diff --git a/libsemanage/src/direct_api.c b/libsemanage/src/direct_api.c
> index 99cba7f7..ce12ccaf 100644
> --- a/libsemanage/src/direct_api.c
> +++ b/libsemanage/src/direct_api.c
> @@ -26,6 +26,7 @@
>
> #include <assert.h>
> #include <fcntl.h>
> +#include <libgen.h>
> #include <stdio.h>
> #include <stdio_ext.h>
> #include <stdlib.h>
> diff --git a/libsemanage/src/utilities.c b/libsemanage/src/utilities.c
> index 70b5b677..004ffb62 100644
> --- a/libsemanage/src/utilities.c
> +++ b/libsemanage/src/utilities.c
> @@ -349,3 +349,12 @@ int write_full(int fd, const void *buf, size_t len)
>
> return 0;
> }
> +
> +#ifdef __GNUC__
> +__attribute__((nonnull))
> +#endif
> +char *semanage_basename(const char *filename)
> +{
> + char *p = strrchr(filename, '/');
> + return p ? p + 1 : (char *)filename;
> +}
> diff --git a/libsemanage/src/utilities.h b/libsemanage/src/utilities.h
> index c2d484a7..7481077a 100644
> --- a/libsemanage/src/utilities.h
> +++ b/libsemanage/src/utilities.h
> @@ -156,4 +156,17 @@ semanage_list_t *semanage_slurp_file_filter(FILE * file,
>
> int write_full(int fd, const void *buf, size_t len) WARN_UNUSED;
>
> +/**
> + * Portable implementation of the glibc version of basename(3).
> + *
> + * @param filename path to find basename of
> + *
> + * @return basename of filename
> + */
> +
> +#ifdef __GNUC__
> +__attribute__((nonnull))
> +#endif
> +char *semanage_basename(const char *filename);
> +
> #endif
> diff --git a/libsemanage/tests/test_utilities.c b/libsemanage/tests/test_utilities.c
> index bbd5af30..70a76fe7 100644
> --- a/libsemanage/tests/test_utilities.c
> +++ b/libsemanage/tests/test_utilities.c
> @@ -46,6 +46,7 @@ static void test_semanage_rtrim(void);
> static void test_semanage_str_replace(void);
> static void test_semanage_findval(void);
> static void test_slurp_file_filter(void);
> +static void test_semanage_basename(void);
>
> static char fname[] = {
> 'T', 'E', 'S', 'T', '_', 'T', 'E', 'M', 'P', '_', 'X', 'X', 'X', 'X',
> @@ -117,6 +118,10 @@ int semanage_utilities_add_tests(CU_pSuite suite)
> test_slurp_file_filter)) {
> goto err;
> }
> + if (NULL == CU_add_test(suite, "semanage_basename",
> + test_semanage_basename)) {
> + goto err;
> + }
> return 0;
> err:
> CU_cleanup_registry();
> @@ -346,3 +351,24 @@ static void test_slurp_file_filter(void)
>
> semanage_list_destroy(&data);
> }
> +
> +static void test_semanage_basename(void)
> +{
> + char *basename1 = semanage_basename("/foo/bar");
> + CU_ASSERT_STRING_EQUAL(basename1, "bar");
> +
> + char *basename2 = semanage_basename("/foo/bar/");
> + CU_ASSERT_STRING_EQUAL(basename2, "");
> +
> + char *basename3 = semanage_basename("/foo.bar");
> + CU_ASSERT_STRING_EQUAL(basename3, "foo.bar");
> +
> + char *basename5 = semanage_basename(".");
> + CU_ASSERT_STRING_EQUAL(basename5, ".");
> +
> + char *basename6 = semanage_basename("");
> + CU_ASSERT_STRING_EQUAL(basename6, "");
> +
> + char *basename7 = semanage_basename("/");
> + CU_ASSERT_STRING_EQUAL(basename7, "");
> +}
> --
> 2.48.1
>
>
