On Mon, Sep 11, 2017 at 11:04 AM, Daniel Cashman <dcashman@xxxxxxxxxxx> wrote:
From: Dan Cashman <dcashman@xxxxxxxxxx>
The file_contexts labeling backend, specified in label_file.c, currently assumes
that only one path will be specified as an option to selabel_open(). The split
of platform and non-platform policy on device, however, will necessitate the
loading of two disparate policy files. Rather than combining the files and then
calling the existing API on a newly-formed file, just add the ability to specify
multiple files to use. Order of opt specification to selabel_open matters.
This corresponds to AOSP commit 50400d38203e4db08314168e60c281cc61a717a8, which
lead to a fork with upstream, which we'd like to correct.
Signed-off-by: Dan Cashman <dcashman@xxxxxxxxxxx>
---
libselinux/src/label.c | 21 +++++---
libselinux/src/label_file.c | 104 +++++++++++++++++++++++++++++-----------
libselinux/src/label_internal.h | 5 +-
3 files changed, 94 insertions(+), 36 deletions(-)
diff --git a/libselinux/src/label.c b/libselinux/src/label.c
index 48f4d2d6..0dfa054c 100644
--- a/libselinux/src/label.c
+++ b/libselinux/src/label.c
@@ -143,7 +143,11 @@ static int selabel_fini(struct selabel_handle *rec,
struct selabel_lookup_rec *lr,
int translating)
{
- if (compat_validate(rec, lr, rec->spec_file, 0))
+ char *path = NULL;
+
+ if (rec->spec_files)
+ path = rec->spec_files[0];
+ if (compat_validate(rec, lr, path, 0))
return -1;
if (translating && !lr->ctx_trans &&
@@ -226,11 +230,9 @@ struct selabel_handle *selabel_open(unsigned int backend,
rec->digest = selabel_is_digest_set(opts, nopts, rec->digest);
if ((*initfuncs[backend])(rec, opts, nopts)) {
- free(rec->spec_file);
- free(rec);
+ selabel_close(rec);
rec = NULL;
}
-
out:
return rec;
}
@@ -337,10 +339,17 @@ int selabel_digest(struct selabel_handle *rec,
void selabel_close(struct selabel_handle *rec)
{
+ size_t i;
+
+ if (rec->spec_files) {
+ for (i = 0; i < rec->spec_files_len; i++)
+ free(rec->spec_files[i]);
+ free(rec->spec_files);
+ }
if (rec->digest)
selabel_digest_fini(rec->digest);
- rec->func_close(rec);
- free(rec->spec_file);
+ if (rec->func_close)
+ rec->func_close(rec);
free(rec);
}
diff --git a/libselinux/src/label_file.c b/libselinux/src/label_file.c
index 560d8c3d..b3b36bc2 100644
--- a/libselinux/src/label_file.c
+++ b/libselinux/src/label_file.c
@@ -709,28 +709,61 @@ static int init(struct selabel_handle *rec, const struct selinux_opt *opts,
unsigned n)
{
struct saved_data *data = "" saved_data *)rec->data;
- const char *path = NULL;
+ size_t num_paths = 0;
+ char **path = NULL;
const char *prefix = NULL;
- int status = -1, baseonly = 0;
+ int status = -1;
+ size_t i;
+ bool baseonly = false;
+ bool path_provided;
/* Process arguments */
- while (n--)
- switch(opts[n].type) {
+ i = n;
+ while (i--)
+ switch(opts[i].type) {
case SELABEL_OPT_PATH:
- path = opts[n].value;
+ num_paths++;
break;
case SELABEL_OPT_SUBSET:
- prefix = opts[n].value;
+ prefix = opts[i].value;
break;
case SELABEL_OPT_BASEONLY:
- baseonly = !!opts[n].value;
+ baseonly = !!opts[i].value;
break;
}
+ if (!num_paths) {
+ num_paths = 1;
+ path_provided = false;
+ } else {
+ path_provided = true;
+ }
+
+ path = calloc(num_paths, sizeof(*path));
+ if (path == NULL) {
+ goto finish;
+ }
+ rec->spec_files = path;
+ rec->spec_files_len = num_paths;
+
+ if (path_provided) {
+ for (i = 0; i < n; i++) {
+ switch(opts[i].type) {
Weird way to do an if/else?
+ case SELABEL_OPT_PATH:
+ *path = strdup(opts[i].value);
+ if (*path == NULL)
+ goto finish;
+ path++;
+ break;
+ default:
+ break;
+ }
+ }
+ }
#if !defined(BUILD_HOST) && !defined(ANDROID)
char subs_file[PATH_MAX + 1];
/* Process local and distribution substitution files */
- if (!path) {
+ if (!path_provided) {
status = selabel_subs_init(
selinux_file_context_subs_dist_path(),
rec->digest, &data->dist_subs);
@@ -740,43 +773,52 @@ static int init(struct selabel_handle *rec, const struct selinux_opt *opts,
rec->digest, &data->subs);
if (status)
goto finish;
- path = selinux_file_context_path();
+ rec->spec_files[0] = strdup(selinux_file_context_path());
+ if (rec->spec_files[0] == NULL)
+ goto finish;
} else {
- snprintf(subs_file, sizeof(subs_file), "%s.subs_dist", path);
- status = selabel_subs_init(subs_file, rec->digest,
+ for (i = 0; i < num_paths; i++) {
+ snprintf(subs_file, sizeof(subs_file), "%s.subs_dist", rec->spec_files[i]);
+ status = selabel_subs_init(subs_file, rec->digest,
&data->dist_subs);
- if (status)
- goto finish;
- snprintf(subs_file, sizeof(subs_file), "%s.subs", path);
- status = selabel_subs_init(subs_file, rec->digest,
+ if (status)
+ goto finish;
+ snprintf(subs_file, sizeof(subs_file), "%s.subs", rec->spec_files[i]);
+ status = selabel_subs_init(subs_file, rec->digest,
&data->subs);
- if (status)
- goto finish;
+ if (status)
+ goto finish;
+ }
+ }
+#else
+ if (!path_provided) {
+ selinux_log(SELINUX_ERROR, "No path given to file labeling backend\n");
+ goto finish;
}
-
#endif
- rec->spec_file = strdup(path);
/*
- * The do detailed validation of the input and fill the spec array
+ * Do detailed validation of the input and fill the spec array
*/
- status = process_file(path, NULL, rec, prefix, rec->digest);
- if (status)
- goto finish;
-
- if (rec->validating) {
- status = nodups_specs(data, path);
+ for (i = 0; i < num_paths; i++) {
+ status = process_file(rec->spec_files[i], NULL, rec, prefix, rec->digest);
if (status)
goto finish;
+
+ if (rec->validating) {
+ status = nodups_specs(data, rec->spec_files[i]);
+ if (status)
+ goto finish;
+ }
}
if (!baseonly) {
- status = process_file(path, "homedirs", rec, prefix,
+ status = process_file(rec->spec_files[0], "homedirs", rec, prefix,
rec->digest);
if (status && errno != ENOENT)
goto finish;
- status = process_file(path, "local", rec, prefix,
+ status = process_file(rec->spec_files[0], "local", rec, prefix,
rec->digest);
if (status && errno != ENOENT)
goto finish;
@@ -804,6 +846,12 @@ static void closef(struct selabel_handle *rec)
struct stem *stem;
unsigned int i;
+ if (!data)
+ return;
+
+ /* make sure successive ->func_close() calls are harmless */
+ rec->data = ""> +
selabel_subs_fini(data->subs);
selabel_subs_fini(data->dist_subs);
diff --git a/libselinux/src/label_internal.h b/libselinux/src/label_ internal.h
index c55efb75..43b63513 100644
--- a/libselinux/src/label_internal.h
+++ b/libselinux/src/label_internal.h
@@ -98,10 +98,11 @@ struct selabel_handle {
void *data;
/*
- * The main spec file used. Note for file contexts the local and/or
+ * The main spec file(s) used. Note for file contexts the local and/or
* homedirs could also have been used to resolve a context.
*/
- char *spec_file;
+ size_t spec_files_len;
+ char **spec_files;
/* ptr to SHA1 hash information if SELABEL_OPT_DIGEST set */
struct selabel_digest *digest;
--
2.14.1.581.gf28d330327-goog
all in all, I have no major gripes with this. Ack.
