X-Git-Url: https://git.lttng.org/?p=lttng-tools.git;a=blobdiff_plain;f=src%2Fcommon%2Fcompat%2Fdirectory-handle.c;h=3f35f91655b58b6da7287b476293f8504088776b;hp=80e9e118b8c46994751f8b7267d52f0718552f89;hb=93bed9fe8f48c11b7bb1224db36d82404cea080d;hpb=bbbfd84979130a11aebf172cf7d0d24e28165258

diff --git a/src/common/compat/directory-handle.c b/src/common/compat/directory-handle.c
index 80e9e118b..3f35f9165 100644
--- a/src/common/compat/directory-handle.c
+++ b/src/common/compat/directory-handle.c
@@ -21,12 +21,14 @@
 #include <common/runas.h>
 #include <common/credentials.h>
 #include <lttng/constant.h>
+#include <common/dynamic-array.h>
 
 #include <assert.h>
 #include <sys/types.h>
 #include <sys/stat.h>
 #include <fcntl.h>
 #include <unistd.h>
+#include <dirent.h>
 
 /*
  * This compatibility layer shares a common "base" that is implemented
@@ -61,6 +63,30 @@ static
 int _run_as_unlink(const struct lttng_directory_handle *handle,
 		const char *filename, uid_t uid, gid_t gid);
 static
+int _lttng_directory_handle_rename(
+		const struct lttng_directory_handle *old_handle,
+		const char *old_name,
+		const struct lttng_directory_handle *new_handle,
+		const char *new_name);
+static
+int _run_as_rename(const struct lttng_directory_handle *old_handle,
+		const char *old_name,
+		const struct lttng_directory_handle *new_handle,
+		const char *new_name, uid_t uid, gid_t gid);
+static
+DIR *lttng_directory_handle_opendir(const struct lttng_directory_handle *handle,
+		const char *path);
+static
+int lttng_directory_handle_rmdir(
+		const struct lttng_directory_handle *handle, const char *name);
+static
+int _run_as_rmdir(const struct lttng_directory_handle *handle,
+		const char *name, uid_t uid, gid_t gid);
+static
+int _run_as_rmdir_recursive(
+		const struct lttng_directory_handle *handle, const char *name,
+		uid_t uid, gid_t gid);
+static
 void lttng_directory_handle_invalidate(struct lttng_directory_handle *handle);
 
 #ifdef COMPAT_DIRFD
@@ -213,6 +239,76 @@ int _run_as_mkdir_recursive(const struct lttng_directory_handle *handle,
 	return run_as_mkdirat_recursive(handle->dirfd, path, mode, uid, gid);
 }
 
+static
+int _lttng_directory_handle_rename(
+		const struct lttng_directory_handle *old_handle,
+		const char *old_name,
+		const struct lttng_directory_handle *new_handle,
+		const char *new_name)
+{
+	return renameat(old_handle->dirfd, old_name,
+			new_handle->dirfd, new_name);
+}
+
+static
+int _run_as_rename(const struct lttng_directory_handle *old_handle,
+		const char *old_name,
+		const struct lttng_directory_handle *new_handle,
+		const char *new_name, uid_t uid, gid_t gid)
+{
+	return run_as_renameat(old_handle->dirfd, old_name, new_handle->dirfd,
+			new_name, uid, gid);
+}
+
+static
+DIR *lttng_directory_handle_opendir(const struct lttng_directory_handle *handle,
+		const char *path)
+{
+	DIR *dir_stream = NULL;
+	int fd = openat(handle->dirfd, path, O_RDONLY);
+
+	if (fd < 0) {
+		goto end;
+	}
+
+	dir_stream = fdopendir(fd);
+	if (!dir_stream) {
+		int ret;
+
+		PERROR("Failed to open directory stream");
+		ret = close(fd);
+		if (ret) {
+			PERROR("Failed to close file descriptor to %s", path);
+		}
+		goto end;
+	}
+
+end:
+	return dir_stream;
+}
+
+static
+int lttng_directory_handle_rmdir(
+		const struct lttng_directory_handle *handle, const char *name)
+{
+	return unlinkat(handle->dirfd, name, AT_REMOVEDIR);
+}
+
+static
+int _run_as_rmdir(const struct lttng_directory_handle *handle,
+		const char *name, uid_t uid, gid_t gid)
+{
+	return run_as_rmdirat(handle->dirfd, name, uid, gid);
+}
+
+static
+int _run_as_rmdir_recursive(
+		const struct lttng_directory_handle *handle, const char *name,
+		uid_t uid, gid_t gid)
+{
+	return run_as_rmdirat_recursive(handle->dirfd, name, uid, gid);
+}
+
 #else /* COMPAT_DIRFD */
 
 static
@@ -220,20 +316,29 @@ int get_full_path(const struct lttng_directory_handle *handle,
 		const char *subdirectory, char *fullpath, size_t size)
 {
 	int ret;
-
-	subdirectory = subdirectory ? : "";
-	/*
-	 * Don't include the base path if subdirectory is absolute.
-	 * This is the same behaviour than mkdirat.
-	 */
-	ret = snprintf(fullpath, size, "%s%s",
-			*subdirectory != '/' ? handle->base_path : "",
-			subdirectory);
+	const bool subdirectory_is_absolute =
+			subdirectory && *subdirectory == '/';
+	const char * const base = subdirectory_is_absolute ?
+			subdirectory : handle->base_path;
+	const char * const end = subdirectory && !subdirectory_is_absolute ?
+			subdirectory : NULL;
+	const size_t base_len = strlen(base);
+	const size_t end_len = end ? strlen(end) : 0;
+	const bool add_separator_slash = end && base[base_len - 1] != '/';
+	const bool add_trailing_slash = end && end[end_len - 1] != '/';
+
+	ret = snprintf(fullpath, size, "%s%s%s%s",
+			base,
+			add_separator_slash ? "/" : "",
+			end ? end : "",
+			add_trailing_slash ? "/" : "");
 	if (ret == -1 || ret >= size) {
 		ERR("Failed to format subdirectory from directory handle");
 		ret = -1;
+		goto end;
 	}
 	ret = 0;
+end:
 	return ret;
 }
 
@@ -242,39 +347,32 @@ int lttng_directory_handle_init(struct lttng_directory_handle *handle,
 		const char *path)
 {
 	int ret;
-	const char *cwd;
+	const char *cwd = "";
 	size_t cwd_len, path_len;
 	char cwd_buf[LTTNG_PATH_MAX] = {};
 	char handle_buf[LTTNG_PATH_MAX] = {};
-	bool add_cwd_slash, add_trailing_slash;
+	bool add_cwd_slash = false, add_trailing_slash = false;
 	const struct lttng_directory_handle cwd_handle = {
 		.base_path = handle_buf,
 	};
 
-	if (path && *path == '/') {
-		/*
-		 * Creation of an handle to an absolute path; no need to sample
-		 * the cwd.
-		 */
-		goto create;
-	}
 	path_len = path ? strlen(path) : 0;
-
-	cwd = getcwd(cwd_buf, sizeof(cwd_buf));
-	if (!cwd) {
-		PERROR("Failed to initialize directory handle, can't get current working directory");
-		ret = -1;
-		goto end;
-	}
-	cwd_len = strlen(cwd);
-	if (cwd_len == 0) {
-		ERR("Failed to initialize directory handle, current working directory path has a length of 0");
-		ret = -1;
-		goto end;
-	}
-
-	add_cwd_slash = cwd[cwd_len - 1] != '/';
 	add_trailing_slash = path && path[path_len - 1] != '/';
+	if (!path || (path && *path != '/')) {
+		cwd = getcwd(cwd_buf, sizeof(cwd_buf));
+		if (!cwd) {
+			PERROR("Failed to initialize directory handle, can't get current working directory");
+			ret = -1;
+			goto end;
+		}
+		cwd_len = strlen(cwd);
+		if (cwd_len == 0) {
+			ERR("Failed to initialize directory handle, current working directory path has a length of 0");
+			ret = -1;
+			goto end;
+		}
+		add_cwd_slash = cwd[cwd_len - 1] != '/';
+	}
 
 	ret = snprintf(handle_buf, sizeof(handle_buf), "%s%s%s%s",
 			cwd,
@@ -285,7 +383,7 @@ int lttng_directory_handle_init(struct lttng_directory_handle *handle,
 		ERR("Failed to initialize directory handle, failed to format directory path");
 		goto end;
 	}
-create:
+
 	ret = lttng_directory_handle_init_from_handle(handle, path,
 			&cwd_handle);
 end:
@@ -545,8 +643,141 @@ end:
 	return ret;
 }
 
+static
+int _lttng_directory_handle_rename(
+		const struct lttng_directory_handle *old_handle,
+		const char *old_name,
+		const struct lttng_directory_handle *new_handle,
+		const char *new_name)
+{
+	int ret;
+	char old_fullpath[LTTNG_PATH_MAX];
+	char new_fullpath[LTTNG_PATH_MAX];
+
+	ret = get_full_path(old_handle, old_name, old_fullpath,
+			sizeof(old_fullpath));
+	if (ret) {
+		errno = ENOMEM;
+		goto end;
+	}
+	ret = get_full_path(new_handle, new_name, new_fullpath,
+			sizeof(new_fullpath));
+	if (ret) {
+		errno = ENOMEM;
+		goto end;
+	}
+
+	ret = rename(old_fullpath, new_fullpath);
+end:
+	return ret;
+}
+
+static
+int _run_as_rename(const struct lttng_directory_handle *old_handle,
+		const char *old_name,
+		const struct lttng_directory_handle *new_handle,
+		const char *new_name, uid_t uid, gid_t gid)
+{
+	int ret;
+	char old_fullpath[LTTNG_PATH_MAX];
+	char new_fullpath[LTTNG_PATH_MAX];
+
+	ret = get_full_path(old_handle, old_name, old_fullpath,
+			sizeof(old_fullpath));
+	if (ret) {
+		errno = ENOMEM;
+		goto end;
+	}
+	ret = get_full_path(new_handle, new_name, new_fullpath,
+			sizeof(new_fullpath));
+	if (ret) {
+		errno = ENOMEM;
+		goto end;
+	}
+
+	ret = run_as_rename(old_fullpath, new_fullpath, uid, gid);
+end:
+	return ret;
+}
+
+static
+DIR *lttng_directory_handle_opendir(const struct lttng_directory_handle *handle,
+		const char *path)
+{
+	int ret;
+	DIR *dir_stream = NULL;
+	char fullpath[LTTNG_PATH_MAX];
+
+	ret = get_full_path(handle, path, fullpath, sizeof(fullpath));
+	if (ret) {
+		errno = ENOMEM;
+		goto end;
+	}
+
+	dir_stream = opendir(fullpath);
+end:
+	return dir_stream;
+}
+
+static
+int lttng_directory_handle_rmdir(
+		const struct lttng_directory_handle *handle, const char *name)
+{
+	int ret;
+	char fullpath[LTTNG_PATH_MAX];
+
+	ret = get_full_path(handle, name, fullpath, sizeof(fullpath));
+	if (ret) {
+		errno = ENOMEM;
+		goto end;
+	}
+
+	ret = rmdir(fullpath);
+end:
+	return ret;
+}
+
+static
+int _run_as_rmdir(const struct lttng_directory_handle *handle,
+		const char *name, uid_t uid, gid_t gid)
+{
+	int ret;
+	char fullpath[LTTNG_PATH_MAX];
+
+	ret = get_full_path(handle, name, fullpath, sizeof(fullpath));
+	if (ret) {
+		errno = ENOMEM;
+		goto end;
+	}
+
+	ret = run_as_rmdir(fullpath, uid, gid);
+end:
+	return ret;
+}
+
+static
+int _run_as_rmdir_recursive(
+		const struct lttng_directory_handle *handle, const char *name,
+		uid_t uid, gid_t gid)
+{
+	int ret;
+	char fullpath[LTTNG_PATH_MAX];
+
+	ret = get_full_path(handle, name, fullpath, sizeof(fullpath));
+	if (ret) {
+		errno = ENOMEM;
+		goto end;
+	}
+
+	ret = run_as_rmdir_recursive(fullpath, uid, gid);
+end:
+	return ret;
+}
+
 #endif /* COMPAT_DIRFD */
 
+/* Common implementation. */
+
 /*
  * On some filesystems (e.g. nfs), mkdir will validate access rights before
  * checking for the existence of the path element. This means that on a setup
@@ -574,6 +805,8 @@ int create_directory_check_exists(const struct lttng_directory_handle *handle,
 			ret = -1;
 			goto end;
 		}
+	} else if (errno != ENOENT) {
+		goto end;
 	}
 
 	/*
@@ -585,7 +818,6 @@ end:
 	return ret;
 }
 
-/* Common implementation. */
 LTTNG_HIDDEN
 struct lttng_directory_handle
 lttng_directory_handle_move(struct lttng_directory_handle *original)
@@ -766,3 +998,228 @@ int lttng_directory_handle_unlink_file(
 	return lttng_directory_handle_unlink_file_as_user(handle,
 			filename, NULL);
 }
+
+LTTNG_HIDDEN
+int lttng_directory_handle_rename(
+		const struct lttng_directory_handle *old_handle,
+		const char *old_name,
+		const struct lttng_directory_handle *new_handle,
+		const char *new_name)
+{
+	return lttng_directory_handle_rename_as_user(old_handle, old_name,
+			new_handle, new_name, NULL);
+}
+
+LTTNG_HIDDEN
+int lttng_directory_handle_rename_as_user(
+		const struct lttng_directory_handle *old_handle,
+		const char *old_name,
+		const struct lttng_directory_handle *new_handle,
+		const char *new_name,
+		const struct lttng_credentials *creds)
+{
+	int ret;
+
+	if (!creds) {
+		/* Run as current user. */
+		ret = _lttng_directory_handle_rename(old_handle,
+				old_name, new_handle, new_name);
+	} else {
+		ret = _run_as_rename(old_handle, old_name, new_handle,
+				new_name, creds->uid, creds->gid);
+	}
+	return ret;
+}
+
+LTTNG_HIDDEN
+int lttng_directory_handle_remove_subdirectory(
+		const struct lttng_directory_handle *handle,
+		const char *name)
+{
+	return lttng_directory_handle_remove_subdirectory_as_user(handle, name,
+			NULL);
+}
+
+LTTNG_HIDDEN
+int lttng_directory_handle_remove_subdirectory_as_user(
+		const struct lttng_directory_handle *handle,
+		const char *name,
+		const struct lttng_credentials *creds)
+{
+	int ret;
+
+	if (!creds) {
+		/* Run as current user. */
+		ret = lttng_directory_handle_rmdir(handle, name);
+	} else {
+		ret = _run_as_rmdir(handle, name, creds->uid, creds->gid);
+	}
+	return ret;
+}
+
+struct rmdir_frame {
+	DIR *dir;
+	/* Size including '\0'. */
+	size_t path_size;
+};
+
+static
+void rmdir_frame_fini(void *data)
+{
+	struct rmdir_frame *frame = data;
+
+	closedir(frame->dir);
+}
+
+static
+int remove_directory_recursive(const struct lttng_directory_handle *handle,
+		const char *path)
+{
+	int ret;
+	struct lttng_dynamic_array frames;
+	size_t current_frame_idx = 0;
+	struct rmdir_frame initial_frame = {
+		.dir = lttng_directory_handle_opendir(handle, path),
+		.path_size = strlen(path) + 1,
+	};
+	struct lttng_dynamic_buffer current_path;
+	const char separator = '/';
+
+	lttng_dynamic_buffer_init(&current_path);
+	lttng_dynamic_array_init(&frames, sizeof(struct rmdir_frame),
+		        rmdir_frame_fini);
+
+	ret = lttng_dynamic_array_add_element(&frames, &initial_frame);
+	if (ret) {
+		ERR("Failed to push context frame during recursive directory removal");
+		rmdir_frame_fini(&initial_frame);
+		goto end;
+	}
+
+	ret = lttng_dynamic_buffer_append(&current_path, path,
+			initial_frame.path_size);
+        if (ret) {
+		ERR("Failed to set initial path during recursive directory removal");
+		ret = -1;
+		goto end;
+        }
+
+        while (lttng_dynamic_array_get_count(&frames) > 0) {
+		struct dirent *entry;
+		struct rmdir_frame *current_frame =
+				lttng_dynamic_array_get_element(&frames,
+						current_frame_idx);
+
+                if (!current_frame->dir) {
+			PERROR("Failed to open directory stream during recursive directory removal");
+			ret = -1;
+			goto end;
+		}
+		ret = lttng_dynamic_buffer_set_size(&current_path,
+				current_frame->path_size);
+		assert(!ret);
+		current_path.data[current_path.size - 1] = '\0';
+
+		while ((entry = readdir(current_frame->dir))) {
+			struct stat st;
+			struct rmdir_frame new_frame;
+
+			if (!strcmp(entry->d_name, ".")
+					|| !strcmp(entry->d_name, "..")) {
+				continue;
+			}
+
+			/* Set current_path to the entry's path. */
+			ret = lttng_dynamic_buffer_set_size(&current_path,
+					current_path.size - 1);
+			assert(!ret);
+			ret = lttng_dynamic_buffer_append(&current_path,
+					&separator, sizeof(separator));
+			if (ret) {
+				goto end;
+			}
+			ret = lttng_dynamic_buffer_append(&current_path,
+					entry->d_name,
+					strlen(entry->d_name) + 1);
+			if (ret) {
+				goto end;
+			}
+
+			if (lttng_directory_handle_stat(handle,
+					current_path.data, &st)) {
+				PERROR("Failed to stat \"%s\"",
+						current_path.data);
+				ret = -1;
+				goto end;
+			}
+
+			if (!S_ISDIR(st.st_mode)) {
+				/* Not empty, abort. */
+				DBG("Directory \"%s\" is not empty; refusing to remove directory",
+						current_path.data);
+				ret = -1;
+				goto end;
+			}
+
+			new_frame.path_size = current_path.size;
+			new_frame.dir = lttng_directory_handle_opendir(handle,
+					current_path.data);
+			ret = lttng_dynamic_array_add_element(&frames,
+					&new_frame);
+                        if (ret) {
+				ERR("Failed to push context frame during recursive directory removal");
+				rmdir_frame_fini(&new_frame);
+				goto end;
+                        }
+			current_frame_idx++;
+			break;
+                }
+		if (!entry) {
+			ret = lttng_directory_handle_rmdir(handle,
+					current_path.data);
+                        if (ret) {
+				PERROR("Failed to remove \"%s\" during recursive directory removal",
+						current_path.data);
+				goto end;
+                        }
+			ret = lttng_dynamic_array_remove_element(&frames,
+					current_frame_idx);
+			if (ret) {
+				ERR("Failed to pop context frame during recursive directory removal");
+				goto end;
+			}
+			current_frame_idx--;
+                }
+	}
+end:
+	lttng_dynamic_array_reset(&frames);
+	lttng_dynamic_buffer_reset(&current_path);
+	return ret;
+}
+
+LTTNG_HIDDEN
+int lttng_directory_handle_remove_subdirectory_recursive(
+		const struct lttng_directory_handle *handle,
+		const char *name)
+{
+	return lttng_directory_handle_remove_subdirectory_recursive_as_user(
+			handle, name, NULL);
+}
+
+LTTNG_HIDDEN
+int lttng_directory_handle_remove_subdirectory_recursive_as_user(
+		const struct lttng_directory_handle *handle,
+		const char *name,
+		const struct lttng_credentials *creds)
+{
+	int ret;
+
+	if (!creds) {
+		/* Run as current user. */
+		ret = remove_directory_recursive(handle, name);
+	} else {
+		ret = _run_as_rmdir_recursive(handle, name, creds->uid,
+				creds->gid);
+	}
+	return ret;
+}