Skip to content

Commit 34ea0eb

Browse files
author
Eric Chanudet
committed
txt_info: add as a patch config fragment
Hosting txt_info.c as an out-of-tree module with its sources in the layer is not very elegant. The changes are small and configurable, and useful only to dom0. Make the out-of-tree module a patch against the kernel and create the associated configuration fragment so dom0's kernel can select it. Signed-off-by: Eric Chanudet <[email protected]>
1 parent 8021af4 commit 34ea0eb

File tree

10 files changed

+232
-213
lines changed

10 files changed

+232
-213
lines changed

‎recipes-core/images/openxt-dom0-image.bb‎

Lines changed: 0 additions & 1 deletion
Original file line numberDiff line numberDiff line change
@@ -42,7 +42,6 @@ IMAGE_INSTALL += "\
4242
packagegroup-xenclient-dom0 \
4343
packagegroup-openxt-test \
4444
argo-module \
45-
txt-info-module \
4645
xenclient-preload-hs-libs \
4746
linux-firmware-i915 \
4847
devicemodel-stubdom \

‎recipes-kernel/linux/files/openxt-kmeta/patches/xen-txt-evtlog/xen-txt-evtlog.cfg‎

Lines changed: 0 additions & 1 deletion
This file was deleted.

‎recipes-kernel/linux/files/openxt-kmeta/patches/xen-txt/0001-txt_info-expose-TXT-conf-registers-to-userland.patch‎

Lines changed: 227 additions & 0 deletions
Original file line numberDiff line numberDiff line change
@@ -0,0 +1,227 @@
1+
From acff0fec046e730871aa7342fe8118479eb092d2 Mon Sep 17 00:00:00 2001
2+
From: Eric Chanudet <[email protected]>
3+
Date: Wed, 23 Jun 2021 10:12:42 -0400
4+
Subject: [PATCH] txt_info: expose TXT conf registers to userland
5+
6+
TXT exposes configuration registers documented in its Software
7+
Development Guide. Accessing these registers in sometimes necessary for
8+
userland software to perform checks and validate compatibility with
9+
software resources.
10+
11+
Expose the previously mentioned resources through a platform device
12+
driver in the sysfs.
13+
14+
Signed-off-by: Eric Chanudet <[email protected]>
15+
---
16+
drivers/misc/Kconfig | 10 +++
17+
drivers/misc/Makefile | 1 +
18+
drivers/misc/txt_info.c | 167 ++++++++++++++++++++++++++++++++++++++++
19+
3 files changed, 178 insertions(+)
20+
create mode 100644 drivers/misc/txt_info.c
21+
22+
diff --git a/drivers/misc/Kconfig b/drivers/misc/Kconfig
23+
index c55b63750757..2d3479593610 100644
24+
--- a/drivers/misc/Kconfig
25+
+++ b/drivers/misc/Kconfig
26+
@@ -466,6 +466,16 @@ config PVPANIC
27+
a paravirtualized device provided by QEMU; it lets a virtual machine
28+
(guest) communicate panic events to the host.
29+
30+
+config TXT_INFO
31+
+ tristate "Add TXT configuration registers in securityfs"
32+
+ depends on X86 && TCG_TPM
33+
+ default n
34+
+ help
35+
+ Expose the values of TXT configuration registers via the sysfs for
36+
+ use in userland. To compile this as a module choose M.
37+
+
38+
+ If unsure, say N.
39+
+
40+
source "drivers/misc/c2port/Kconfig"
41+
source "drivers/misc/eeprom/Kconfig"
42+
source "drivers/misc/cb710/Kconfig"
43+
diff --git a/drivers/misc/Makefile b/drivers/misc/Makefile
44+
index c1860d35dc7e..4ebacab15df2 100644
45+
--- a/drivers/misc/Makefile
46+
+++ b/drivers/misc/Makefile
47+
@@ -57,3 +57,4 @@ obj-y += cardreader/
48+
obj-$(CONFIG_PVPANIC) += pvpanic.o
49+
obj-$(CONFIG_HABANA_AI) += habanalabs/
50+
obj-$(CONFIG_XILINX_SDFEC) += xilinx_sdfec.o
51+
+obj-$(CONFIG_TXT_INFO) += txt_info.o
52+
diff --git a/drivers/misc/txt_info.c b/drivers/misc/txt_info.c
53+
new file mode 100644
54+
index 000000000000..ebece6a50612
55+
--- /dev/null
56+
+++ b/drivers/misc/txt_info.c
57+
@@ -0,0 +1,167 @@
58+
+#include <linux/kobject.h>
59+
+#include <linux/module.h>
60+
+#include <linux/device.h>
61+
+#include <linux/platform_device.h>
62+
+#include <linux/io.h>
63+
+
64+
+#define TXT_PUB_CR_BASE 0xfed30000
65+
+#define TXT_PUB_CR_SIZE 0x10000
66+
+static const struct resource txt_resources[] = {
67+
+ {
68+
+ .start = TXT_PUB_CR_BASE,
69+
+ .end = TXT_PUB_CR_BASE + TXT_PUB_CR_SIZE - 1,
70+
+ .flags = IORESOURCE_MEM,
71+
+ },
72+
+};
73+
+#define TXT_PUB_CR_INDEX 0
74+
+
75+
+struct platform_device *pdev;
76+
+struct txt_info {
77+
+ void __iomem *cr_pub;
78+
+ void __iomem *cr_priv;
79+
+};
80+
+static struct txt_info txt_info;
81+
+
82+
+static void __iomem *txt_info_map_regs(struct platform_device *pdev,
83+
+ size_t index)
84+
+{
85+
+ struct resource *res;
86+
+ void __iomem *base;
87+
+
88+
+ res = platform_get_resource(pdev, IORESOURCE_MEM, index);
89+
+ if (IS_ERR(res)) {
90+
+ dev_dbg(&pdev->dev,
91+
+ "Failed to access IOMEM resource %zu.\n", index);
92+
+ return res;
93+
+ }
94+
+
95+
+ base = devm_ioremap(&pdev->dev, res->start, resource_size(res));
96+
+ if (IS_ERR(base))
97+
+ dev_dbg(&pdev->dev,
98+
+ "Failed to ioremap configuration registers.\n");
99+
+
100+
+ return base;
101+
+}
102+
+
103+
+/* Registers offset from TXT_PUB_CR_BASE */
104+
+#define TXT_STS_OFFSET 0x000
105+
+#define TXT_ESTS_OFFSET 0x008
106+
+#define TXT_ERRORCODE_OFFSET 0x030
107+
+#define TXT_VER_FSBIF_OFFSET 0x100
108+
+#define TXT_DIDVID_OFFSET 0x110
109+
+#define TXT_VER_QPIIF_OFFSET 0x200
110+
+
111+
+#define DECLARE_PUB_SHOW_U8(name, offset) \
112+
+static ssize_t name##_show(struct kobject *kobj, \
113+
+ struct kobj_attribute *attr, char *buf) \
114+
+{ \
115+
+ uint8_t v = ioread8(txt_info.cr_pub + (offset)); \
116+
+ return sprintf(buf, "%#04x\n", v); \
117+
+} \
118+
+static struct kobj_attribute txt_attr_##name = __ATTR_RO(name);
119+
+
120+
+#define DECLARE_PUB_SHOW_U32(name, offset) \
121+
+static ssize_t name##_show(struct kobject *kobj, \
122+
+ struct kobj_attribute *attr, char *buf) \
123+
+{ \
124+
+ uint32_t v = ioread32(txt_info.cr_pub + (offset)); \
125+
+ return sprintf(buf, "%#010x\n", v); \
126+
+} \
127+
+static struct kobj_attribute txt_attr_##name = __ATTR_RO(name);
128+
+
129+
+#define DECLARE_PUB_SHOW_U64(name, offset) \
130+
+static ssize_t name##_show(struct kobject *kobj, \
131+
+ struct kobj_attribute *attr, char *buf) \
132+
+{ \
133+
+ uint64_t v = ioread32(txt_info.cr_pub + (offset) + 0x4); \
134+
+ v <<= 32; \
135+
+ v |= ioread32(txt_info.cr_pub + (offset)); \
136+
+ return sprintf(buf, "%#018llx\n", v); \
137+
+} \
138+
+static struct kobj_attribute txt_attr_##name = __ATTR_RO(name);
139+
+
140+
+DECLARE_PUB_SHOW_U64(sts, TXT_STS_OFFSET);
141+
+DECLARE_PUB_SHOW_U8(ests, TXT_ESTS_OFFSET);
142+
+DECLARE_PUB_SHOW_U32(errorcode, TXT_ERRORCODE_OFFSET);
143+
+DECLARE_PUB_SHOW_U32(ver_fsbif, TXT_VER_FSBIF_OFFSET);
144+
+DECLARE_PUB_SHOW_U64(didvid, TXT_DIDVID_OFFSET);
145+
+DECLARE_PUB_SHOW_U32(ver_qpiif, TXT_VER_QPIIF_OFFSET);
146+
+
147+
+static struct attribute *txt_subsys_attrs[] = {
148+
+ &txt_attr_sts.attr,
149+
+ &txt_attr_ests.attr,
150+
+ &txt_attr_errorcode.attr,
151+
+ &txt_attr_ver_fsbif.attr,
152+
+ &txt_attr_didvid.attr,
153+
+ &txt_attr_ver_qpiif.attr,
154+
+ NULL,
155+
+};
156+
+
157+
+static umode_t txt_attr_is_visible(struct kobject *kobj,
158+
+ struct attribute *attr, int n)
159+
+{
160+
+ return attr->mode;
161+
+}
162+
+
163+
+static const struct attribute_group txt_subsys_attr_group = {
164+
+ .attrs = txt_subsys_attrs,
165+
+ .is_visible = txt_attr_is_visible,
166+
+};
167+
+
168+
+struct kobject *txt_kobj;
169+
+
170+
+static int __init init_txt_info(void)
171+
+{
172+
+ int rc;
173+
+ void __iomem *base;
174+
+
175+
+ pr_info("%s\n", __func__);
176+
+
177+
+ pdev = platform_device_register_simple(
178+
+ "txt", -1, txt_resources, ARRAY_SIZE(txt_resources));
179+
+ if (IS_ERR(pdev)) {
180+
+ rc = PTR_ERR(pdev);
181+
+ pr_err("Failed to register txt platform device driver (%d).\n", rc);
182+
+ goto fail_register;
183+
+ }
184+
+
185+
+ base = txt_info_map_regs(pdev, TXT_PUB_CR_INDEX);
186+
+ if (IS_ERR(base)) {
187+
+ rc = PTR_ERR(base);
188+
+ dev_err(&pdev->dev,
189+
+ "Failed to map TXT public resources (%d).\n", rc);
190+
+ goto fail_map_pub;
191+
+ }
192+
+ txt_info.cr_pub = base;
193+
+
194+
+ rc = sysfs_create_group(&pdev->dev.kobj, &txt_subsys_attr_group);
195+
+ if (rc) {
196+
+ dev_err(&pdev->dev, "Failed to create sysfs group (%d).\n", rc);
197+
+ goto fail_sysfs;
198+
+ }
199+
+
200+
+ return 0;
201+
+
202+
+fail_sysfs:
203+
+ devm_iounmap(&pdev->dev, txt_info.cr_pub);
204+
+fail_map_pub:
205+
+ platform_device_unregister(pdev);
206+
+fail_register:
207+
+ return rc;
208+
+}
209+
+
210+
+static void __exit cleanup_txt_info(void)
211+
+{
212+
+ pr_info("%s\n", __func__);
213+
+
214+
+ if (pdev)
215+
+ platform_device_unregister(pdev);
216+
+}
217+
+
218+
+module_init(init_txt_info);
219+
+module_exit(cleanup_txt_info);
220+
+
221+
+MODULE_AUTHOR("Assured Information Security, Inc");
222+
+MODULE_DESCRIPTION("TXT driver.");
223+
+MODULE_VERSION("1.0");
224+
+MODULE_LICENSE("GPL");
225+
--
226+
2.17.1
227+

‎recipes-kernel/linux/files/openxt-kmeta/patches/xen-txt-evtlog/xen-txt-add-xen-txt-eventlog-module.patch‎ renamed to ‎recipes-kernel/linux/files/openxt-kmeta/patches/xen-txt/xen-txt-add-xen-txt-eventlog-module.patch‎

File renamed without changes.

‎recipes-kernel/linux/files/openxt-kmeta/patches/xen-txt/xen-txt.cfg‎

Lines changed: 2 additions & 0 deletions
Original file line numberDiff line numberDiff line change
@@ -0,0 +1,2 @@
1+
CONFIG_XEN_TXT=y
2+
CONTIG_TXT_INFO=y

‎recipes-kernel/linux/files/openxt-kmeta/patches/xen-txt-evtlog/xen-txt-evtlog.scc‎ renamed to ‎recipes-kernel/linux/files/openxt-kmeta/patches/xen-txt/xen-txt.scc‎

Lines changed: 3 additions & 1 deletion
Original file line numberDiff line numberDiff line change
@@ -4,5 +4,7 @@ define KFEATURE_COMPATIBILITY all
44

55
# Use Xen custom hypercall to retrieve and expose the eventlog in the securityfs.
66
patch xen-txt-add-xen-txt-eventlog-module.patch
7+
# Add a small platform device to expose TXT configuration registers in the securityfs.
8+
patch 0001-txt_info-expose-TXT-conf-registers-to-userland.patch
79

8-
kconf hardware xen-txt-evtlog.cfg
10+
kconf hardware xen-txt.cfg

‎recipes-openxt/txt-info-module/files/sources/Kbuild‎

Lines changed: 0 additions & 3 deletions
This file was deleted.

‎recipes-openxt/txt-info-module/files/sources/Makefile‎

Lines changed: 0 additions & 20 deletions
This file was deleted.

0 commit comments

Comments
 (0)