From 3fc30f8764bcc7c41edad9109cbb645c5564e40e Mon Sep 17 00:00:00 2001
From: midipix <writeonce@midipix.org>
Date: Jun 26 2020 20:48:26 +0000
Subject: driver: toks_set_tmpfs_from_uuid(): initial implementation and integration.


---

diff --git a/src/driver/toks_driver_ctx.c b/src/driver/toks_driver_ctx.c
index 8853e17..efcfc86 100644
--- a/src/driver/toks_driver_ctx.c
+++ b/src/driver/toks_driver_ctx.c
@@ -22,6 +22,8 @@
 #include "toksvc_driver_impl.h"
 #include "argv/argv.h"
 
+#undef   strlen
+
 /* pty integration */
 #include <psxtypes/section/freestd.h>
 
@@ -267,6 +269,135 @@ static int toks_split_argv(
 	return 0;
 }
 
+static int32_t toks_set_tmpfs_from_uuid(struct toks_driver_ctx_impl * ctx)
+{
+	int32_t						status;
+	void *						htmproot;
+	void *						hsvcroot;
+	nt_oa						oa;
+	nt_iosb						iosb;
+	nt_unicode_string				path;
+	uint32_t					access;
+	nt_sd_common_buffer				sd;
+	nt_large_integer				alloc_size;
+	nt_guid_str_utf16				guidstr;
+	uint32_t					access_owner;
+	uint32_t					access_group;
+	uint32_t					access_other;
+	uint32_t					access_admin;
+	wchar16_t					tmproot[3] = {'t','m','p'};
+	wchar16_t					toksvc[6]  = {'t','o','k','s','v','c'};
+
+	/* sd */
+	access_owner  = NT_GENERIC_ALL|NT_SEC_SPECIFIC_RIGHTS_ALL;
+	access_admin  = access_owner;
+
+	access_group  = NT_GENERIC_READ | NT_GENERIC_WRITE | NT_GENERIC_EXECUTE;
+	access_group |= NT_SEC_READ_CONTROL | NT_FILE_READ_ATTRIBUTES;
+
+	access_other  = NT_GENERIC_READ | NT_GENERIC_EXECUTE;
+	access_other |= NT_SEC_READ_CONTROL | NT_FILE_READ_ATTRIBUTES;
+
+	ntapi->acl_init_common_descriptor(
+		&sd,0,0,0,0,
+		access_owner,access_group,access_other,
+		access_admin,access_owner,
+		0);
+
+	/* oa */
+	oa.len      = sizeof(nt_oa);
+	oa.root_dir = 0;
+	oa.obj_name = &path;
+	oa.obj_attr = 0;
+	oa.sec_desc = &sd.sd;
+	oa.sec_qos  = 0;
+
+	/* alloc_size (always zero) */
+	alloc_size.quad = 0;
+
+	/* access */
+	access  = NT_SEC_SYNCHRONIZE | NT_SEC_READ_CONTROL | NT_FILE_READ_ATTRIBUTES;
+	access |= NT_FILE_LIST_DIRECTORY | NT_FILE_ADD_FILE | NT_FILE_ADD_SUBDIRECTORY;
+	access |= NT_FILE_TRAVERSE | NT_FILE_DELETE_CHILD;
+
+	/* /tmp or alternative */
+	if (ctx->rtdata->htmpfslroot) {
+		if ((status = ntapi->zw_duplicate_object(
+				ctx->rtdata->hself,
+				ctx->rtdata->htmpfslroot,
+				ctx->rtdata->hself,
+				&htmproot,
+				0,0,
+				NT_DUPLICATE_SAME_ATTRIBUTES|NT_DUPLICATE_SAME_ACCESS)))
+			return status;
+	} else {
+		path.maxlen = 0;
+		path.strlen = sizeof(tmproot);
+		path.buffer = tmproot;
+
+		oa.root_dir = ctx->rtdata->hroot;
+
+		if ((status = ntapi->zw_create_file(
+				&htmproot,
+				access,&oa,&iosb,
+				&alloc_size,
+				NT_FILE_ATTRIBUTE_DIRECTORY,
+				NT_FILE_SHARE_READ | NT_FILE_SHARE_WRITE | NT_FILE_SHARE_DELETE,
+				NT_FILE_OPEN_IF,
+				NT_FILE_DIRECTORY_FILE | NT_FILE_SYNCHRONOUS_IO_ALERT,
+				0,0)))
+			return status;
+	}
+
+	/* service tmpfs root */
+	path.maxlen = 0;
+	path.strlen = sizeof(toksvc);
+	path.buffer = toksvc;
+
+	oa.root_dir = htmproot;
+
+	status = ntapi->zw_create_file(
+		&hsvcroot,
+		access,&oa,&iosb,
+		&alloc_size,
+		NT_FILE_ATTRIBUTE_DIRECTORY,
+		NT_FILE_SHARE_READ | NT_FILE_SHARE_WRITE | NT_FILE_SHARE_DELETE,
+		NT_FILE_OPEN_IF,
+		NT_FILE_DIRECTORY_FILE | NT_FILE_SYNCHRONOUS_IO_ALERT,
+		0,0);
+
+	if (status) {
+		ntapi->zw_close(htmproot);
+		return status;
+	}
+
+	/* instance-specific tmpfs root */
+	ntapi->tt_guid_to_string_utf16(
+		&ctx->uuid,
+		&guidstr);
+
+	path.maxlen = 0;
+	path.strlen = sizeof(guidstr);
+	path.buffer = &guidstr.lbrace;
+
+	oa.root_dir = hsvcroot;
+
+	status = ntapi->zw_create_file(
+		&ctx->htmpfs,
+		access,&oa,&iosb,
+		&alloc_size,
+		NT_FILE_ATTRIBUTE_DIRECTORY,
+		NT_FILE_SHARE_READ | NT_FILE_SHARE_WRITE | NT_FILE_SHARE_DELETE,
+		NT_FILE_OPEN_IF,
+		NT_FILE_DIRECTORY_FILE | NT_FILE_SYNCHRONOUS_IO_ALERT,
+		0,0);
+
+	ntapi->zw_close(hsvcroot);
+	ntapi->zw_close(htmproot);
+
+	return status;
+}
+
 static int32_t toks_set_uuid_from_root(
 	struct toks_driver_ctx_impl *   ctx,
 	struct _nt_guid *               svcguid)
@@ -712,6 +843,15 @@ int toks_get_driver_ctx(
 	toks_set_driver_refstr(&ctx->ctx,refstr);
 
 	if (cctx.drvflags & TOKS_DRIVER_MODE_SERVER) {
+		if ((status = toks_set_tmpfs_from_uuid(ctx))) {
+			if (flags & TOKS_DRIVER_VERBOSITY_ERRORS)
+				toks_dprintf(STDERR_FILENO,
+					"%s: error: could not create or open "
+					"the instance-specific tmpfs directory [0x%08x].",
+					program,status);
+			return toks_get_driver_ctx_fail(meta);
+		}
+
 		if (!(ctx->waiters = toks_calloc(
 				TOKS_MAX_WAITERS,
 				sizeof(struct toks_waiter))))
@@ -821,6 +961,9 @@ int toks_get_driver_ctx(
 
 static void toks_free_driver_ctx_impl(struct toks_driver_ctx_alloc * ictx)
 {
+	if (ictx->ctx.htmpfs)
+		ntapi->zw_close(ictx->ctx.htmpfs);
+
 	if (ictx->ctx.hevent)
 		ntapi->zw_close(ictx->ctx.hevent);
 
diff --git a/src/internal/toksvc_driver_impl.h b/src/internal/toksvc_driver_impl.h
index ad88393..a18939e 100644
--- a/src/internal/toksvc_driver_impl.h
+++ b/src/internal/toksvc_driver_impl.h
@@ -70,6 +70,7 @@ struct toks_driver_ctx_impl {
 	void *			hservice;
 	void *			hserver;
 	void *			hlog;
+	void *			htmpfs;
 	int			nwaiters;
 	int			ntokens;
 	int			atokens;