55 * Copyright (C) 2022 Intel Corporation
66 */
77
8+ #define pr_fmt (fmt ) KBUILD_MODNAME ": " fmt
9+
810#include <linux/kernel.h>
911#include <linux/miscdevice.h>
1012#include <linux/mm.h>
1517#include <linux/set_memory.h>
1618#include <linux/io.h>
1719#include <linux/delay.h>
20+ #include <linux/sockptr.h>
1821#include <linux/tsm.h>
19- #include <linux/sizes .h>
22+ #include <linux/tsm-mr .h>
2023
2124#include <uapi/linux/tdx-guest.h>
2225
2326#include <asm/cpu_device_id.h>
2427#include <asm/tdx.h>
2528
29+ /* TDREPORT buffer */
30+ static u8 * tdx_report_buf ;
31+
32+ /* Lock to serialize TDG.MR.REPORT and TDG.MR.RTMR.EXTEND TDCALLs */
33+ static DEFINE_MUTEX (mr_lock );
34+
35+ /* TDREPORT fields */
36+ enum {
37+ TDREPORT_reportdata = 128 ,
38+ TDREPORT_tee_tcb_info = 256 ,
39+ TDREPORT_tdinfo = TDREPORT_tee_tcb_info + 256 ,
40+ TDREPORT_attributes = TDREPORT_tdinfo ,
41+ TDREPORT_xfam = TDREPORT_attributes + sizeof (u64 ),
42+ TDREPORT_mrtd = TDREPORT_xfam + sizeof (u64 ),
43+ TDREPORT_mrconfigid = TDREPORT_mrtd + SHA384_DIGEST_SIZE ,
44+ TDREPORT_mrowner = TDREPORT_mrconfigid + SHA384_DIGEST_SIZE ,
45+ TDREPORT_mrownerconfig = TDREPORT_mrowner + SHA384_DIGEST_SIZE ,
46+ TDREPORT_rtmr0 = TDREPORT_mrownerconfig + SHA384_DIGEST_SIZE ,
47+ TDREPORT_rtmr1 = TDREPORT_rtmr0 + SHA384_DIGEST_SIZE ,
48+ TDREPORT_rtmr2 = TDREPORT_rtmr1 + SHA384_DIGEST_SIZE ,
49+ TDREPORT_rtmr3 = TDREPORT_rtmr2 + SHA384_DIGEST_SIZE ,
50+ TDREPORT_servtd_hash = TDREPORT_rtmr3 + SHA384_DIGEST_SIZE ,
51+ };
52+
53+ static int tdx_do_report (sockptr_t data , sockptr_t tdreport )
54+ {
55+ scoped_cond_guard (mutex_intr , return - EINTR , & mr_lock ) {
56+ u8 * reportdata = tdx_report_buf + TDREPORT_reportdata ;
57+ int ret ;
58+
59+ if (!sockptr_is_null (data ) &&
60+ copy_from_sockptr (reportdata , data , TDX_REPORTDATA_LEN ))
61+ return - EFAULT ;
62+
63+ ret = tdx_mcall_get_report0 (reportdata , tdx_report_buf );
64+ if (WARN_ONCE (ret , "tdx_mcall_get_report0() failed: %d" , ret ))
65+ return ret ;
66+
67+ if (!sockptr_is_null (tdreport ) &&
68+ copy_to_sockptr (tdreport , tdx_report_buf , TDX_REPORT_LEN ))
69+ return - EFAULT ;
70+ }
71+ return 0 ;
72+ }
73+
74+ static int tdx_do_extend (u8 mr_ind , const u8 * data )
75+ {
76+ scoped_cond_guard (mutex_intr , return - EINTR , & mr_lock ) {
77+ /*
78+ * TDX requires @extend_buf to be 64-byte aligned.
79+ * It's safe to use REPORTDATA buffer for that purpose because
80+ * tdx_mr_report/extend_lock() are mutually exclusive.
81+ */
82+ u8 * extend_buf = tdx_report_buf + TDREPORT_reportdata ;
83+ int ret ;
84+
85+ memcpy (extend_buf , data , SHA384_DIGEST_SIZE );
86+
87+ ret = tdx_mcall_extend_rtmr (mr_ind , extend_buf );
88+ if (WARN_ONCE (ret , "tdx_mcall_extend_rtmr(%u) failed: %d" , mr_ind , ret ))
89+ return ret ;
90+ }
91+ return 0 ;
92+ }
93+
94+ #define TDX_MR_ (r ) .mr_value = (void *)TDREPORT_##r, TSM_MR_(r, SHA384)
95+ static struct tsm_measurement_register tdx_mrs [] = {
96+ { TDX_MR_ (rtmr0 ) | TSM_MR_F_RTMR },
97+ { TDX_MR_ (rtmr1 ) | TSM_MR_F_RTMR },
98+ { TDX_MR_ (rtmr2 ) | TSM_MR_F_RTMR },
99+ { TDX_MR_ (rtmr3 ) | TSM_MR_F_RTMR },
100+ { TDX_MR_ (mrtd ) },
101+ { TDX_MR_ (mrconfigid ) | TSM_MR_F_NOHASH },
102+ { TDX_MR_ (mrowner ) | TSM_MR_F_NOHASH },
103+ { TDX_MR_ (mrownerconfig ) | TSM_MR_F_NOHASH },
104+ };
105+ #undef TDX_MR_
106+
107+ static int tdx_mr_refresh (const struct tsm_measurements * tm )
108+ {
109+ return tdx_do_report (KERNEL_SOCKPTR (NULL ), KERNEL_SOCKPTR (NULL ));
110+ }
111+
112+ static int tdx_mr_extend (const struct tsm_measurements * tm ,
113+ const struct tsm_measurement_register * mr ,
114+ const u8 * data )
115+ {
116+ return tdx_do_extend (mr - tm -> mrs , data );
117+ }
118+
119+ static struct tsm_measurements tdx_measurements = {
120+ .mrs = tdx_mrs ,
121+ .nr_mrs = ARRAY_SIZE (tdx_mrs ),
122+ .refresh = tdx_mr_refresh ,
123+ .write = tdx_mr_extend ,
124+ };
125+
126+ static const struct attribute_group * tdx_mr_init (void )
127+ {
128+ const struct attribute_group * g ;
129+ int rc ;
130+
131+ u8 * buf __free (kfree ) = kzalloc (TDX_REPORT_LEN , GFP_KERNEL );
132+ if (!buf )
133+ return ERR_PTR (- ENOMEM );
134+
135+ tdx_report_buf = buf ;
136+ rc = tdx_mr_refresh (& tdx_measurements );
137+ if (rc )
138+ return ERR_PTR (rc );
139+
140+ /*
141+ * @mr_value was initialized with the offset only, while the base
142+ * address is being added here.
143+ */
144+ for (size_t i = 0 ; i < ARRAY_SIZE (tdx_mrs ); ++ i )
145+ * (long * )& tdx_mrs [i ].mr_value += (long )buf ;
146+
147+ g = tsm_mr_create_attribute_group (& tdx_measurements );
148+ if (!IS_ERR (g ))
149+ tdx_report_buf = no_free_ptr (buf );
150+
151+ return g ;
152+ }
153+
154+ static void tdx_mr_deinit (const struct attribute_group * mr_grp )
155+ {
156+ tsm_mr_free_attribute_group (mr_grp );
157+ kfree (tdx_report_buf );
158+ }
159+
26160/*
27161 * Intel's SGX QE implementation generally uses Quote size less
28162 * than 8K (2K Quote data + ~5K of certificate blob).
@@ -285,10 +419,16 @@ static const struct file_operations tdx_guest_fops = {
285419 .unlocked_ioctl = tdx_guest_ioctl ,
286420};
287421
422+ static const struct attribute_group * tdx_attr_groups [] = {
423+ NULL , /* measurements */
424+ NULL
425+ };
426+
288427static struct miscdevice tdx_misc_dev = {
289428 .name = KBUILD_MODNAME ,
290429 .minor = MISC_DYNAMIC_MINOR ,
291430 .fops = & tdx_guest_fops ,
431+ .groups = tdx_attr_groups ,
292432};
293433
294434static const struct x86_cpu_id tdx_guest_ids [] = {
@@ -311,9 +451,13 @@ static int __init tdx_guest_init(void)
311451 if (!x86_match_cpu (tdx_guest_ids ))
312452 return - ENODEV ;
313453
454+ tdx_attr_groups [0 ] = tdx_mr_init ();
455+ if (IS_ERR (tdx_attr_groups [0 ]))
456+ return PTR_ERR (tdx_attr_groups [0 ]);
457+
314458 ret = misc_register (& tdx_misc_dev );
315459 if (ret )
316- return ret ;
460+ goto deinit_mr ;
317461
318462 quote_data = alloc_quote_buf ();
319463 if (!quote_data ) {
@@ -332,6 +476,8 @@ static int __init tdx_guest_init(void)
332476 free_quote_buf (quote_data );
333477free_misc :
334478 misc_deregister (& tdx_misc_dev );
479+ deinit_mr :
480+ tdx_mr_deinit (tdx_attr_groups [0 ]);
335481
336482 return ret ;
337483}
@@ -342,6 +488,7 @@ static void __exit tdx_guest_exit(void)
342488 tsm_unregister (& tdx_tsm_ops );
343489 free_quote_buf (quote_data );
344490 misc_deregister (& tdx_misc_dev );
491+ tdx_mr_deinit (tdx_attr_groups [0 ]);
345492}
346493module_exit (tdx_guest_exit );
347494
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