1  // SPDX-License-Identifier: GPL-2.0-only
2  /* Copyright(c) 2022 Intel Corporation. */
3  
4  #include <linux/bitfield.h>
5  #include <linux/module.h>
6  #include <linux/kdev_t.h>
7  #include <linux/semaphore.h>
8  #include <linux/slab.h>
9  
10  #include <asm/cpu_device_id.h>
11  
12  #include "ifs.h"
13  
14  #define X86_MATCH(vfm, array_gen)				\
15  	X86_MATCH_VFM_FEATURE(vfm, X86_FEATURE_CORE_CAPABILITIES, array_gen)
16  
17  static const struct x86_cpu_id ifs_cpu_ids[] __initconst = {
18  	X86_MATCH(INTEL_SAPPHIRERAPIDS_X, ARRAY_GEN0),
19  	X86_MATCH(INTEL_EMERALDRAPIDS_X, ARRAY_GEN0),
20  	X86_MATCH(INTEL_GRANITERAPIDS_X, ARRAY_GEN0),
21  	X86_MATCH(INTEL_GRANITERAPIDS_D, ARRAY_GEN0),
22  	X86_MATCH(INTEL_ATOM_CRESTMONT_X, ARRAY_GEN1),
23  	{}
24  };
25  MODULE_DEVICE_TABLE(x86cpu, ifs_cpu_ids);
26  
27  ATTRIBUTE_GROUPS(plat_ifs);
28  ATTRIBUTE_GROUPS(plat_ifs_array);
29  
30  bool *ifs_pkg_auth;
31  
32  static const struct ifs_test_caps scan_test = {
33  	.integrity_cap_bit = MSR_INTEGRITY_CAPS_PERIODIC_BIST_BIT,
34  	.test_num = IFS_TYPE_SAF,
35  	.image_suffix = "scan",
36  };
37  
38  static const struct ifs_test_caps array_test = {
39  	.integrity_cap_bit = MSR_INTEGRITY_CAPS_ARRAY_BIST_BIT,
40  	.test_num = IFS_TYPE_ARRAY_BIST,
41  };
42  
43  static const struct ifs_test_msrs scan_msrs = {
44  	.copy_hashes = MSR_COPY_SCAN_HASHES,
45  	.copy_hashes_status = MSR_SCAN_HASHES_STATUS,
46  	.copy_chunks = MSR_AUTHENTICATE_AND_COPY_CHUNK,
47  	.copy_chunks_status = MSR_CHUNKS_AUTHENTICATION_STATUS,
48  	.test_ctrl = MSR_SAF_CTRL,
49  };
50  
51  static const struct ifs_test_msrs sbaf_msrs = {
52  	.copy_hashes = MSR_COPY_SBAF_HASHES,
53  	.copy_hashes_status = MSR_SBAF_HASHES_STATUS,
54  	.copy_chunks = MSR_AUTHENTICATE_AND_COPY_SBAF_CHUNK,
55  	.copy_chunks_status = MSR_SBAF_CHUNKS_AUTHENTICATION_STATUS,
56  	.test_ctrl = MSR_SBAF_CTRL,
57  };
58  
59  static const struct ifs_test_caps sbaf_test = {
60  	.integrity_cap_bit = MSR_INTEGRITY_CAPS_SBAF_BIT,
61  	.test_num = IFS_TYPE_SBAF,
62  	.image_suffix = "sbft",
63  };
64  
65  static struct ifs_device ifs_devices[] = {
66  	[IFS_TYPE_SAF] = {
67  		.test_caps = &scan_test,
68  		.test_msrs = &scan_msrs,
69  		.misc = {
70  			.name = "intel_ifs_0",
71  			.minor = MISC_DYNAMIC_MINOR,
72  			.groups = plat_ifs_groups,
73  		},
74  	},
75  	[IFS_TYPE_ARRAY_BIST] = {
76  		.test_caps = &array_test,
77  		.misc = {
78  			.name = "intel_ifs_1",
79  			.minor = MISC_DYNAMIC_MINOR,
80  			.groups = plat_ifs_array_groups,
81  		},
82  	},
83  	[IFS_TYPE_SBAF] = {
84  		.test_caps = &sbaf_test,
85  		.test_msrs = &sbaf_msrs,
86  		.misc = {
87  			.name = "intel_ifs_2",
88  			.minor = MISC_DYNAMIC_MINOR,
89  			.groups = plat_ifs_groups,
90  		},
91  	},
92  };
93  
94  #define IFS_NUMTESTS ARRAY_SIZE(ifs_devices)
95  
ifs_cleanup(void)96  static void ifs_cleanup(void)
97  {
98  	int i;
99  
100  	for (i = 0; i < IFS_NUMTESTS; i++) {
101  		if (ifs_devices[i].misc.this_device)
102  			misc_deregister(&ifs_devices[i].misc);
103  	}
104  	kfree(ifs_pkg_auth);
105  }
106  
ifs_init(void)107  static int __init ifs_init(void)
108  {
109  	const struct x86_cpu_id *m;
110  	u64 msrval;
111  	int i, ret;
112  
113  	m = x86_match_cpu(ifs_cpu_ids);
114  	if (!m)
115  		return -ENODEV;
116  
117  	if (rdmsrl_safe(MSR_IA32_CORE_CAPS, &msrval))
118  		return -ENODEV;
119  
120  	if (!(msrval & MSR_IA32_CORE_CAPS_INTEGRITY_CAPS))
121  		return -ENODEV;
122  
123  	if (rdmsrl_safe(MSR_INTEGRITY_CAPS, &msrval))
124  		return -ENODEV;
125  
126  	ifs_pkg_auth = kmalloc_array(topology_max_packages(), sizeof(bool), GFP_KERNEL);
127  	if (!ifs_pkg_auth)
128  		return -ENOMEM;
129  
130  	for (i = 0; i < IFS_NUMTESTS; i++) {
131  		if (!(msrval & BIT(ifs_devices[i].test_caps->integrity_cap_bit)))
132  			continue;
133  		ifs_devices[i].rw_data.generation = FIELD_GET(MSR_INTEGRITY_CAPS_SAF_GEN_MASK,
134  							      msrval);
135  		ifs_devices[i].rw_data.array_gen = (u32)m->driver_data;
136  		ret = misc_register(&ifs_devices[i].misc);
137  		if (ret)
138  			goto err_exit;
139  	}
140  	return 0;
141  
142  err_exit:
143  	ifs_cleanup();
144  	return ret;
145  }
146  
ifs_exit(void)147  static void __exit ifs_exit(void)
148  {
149  	ifs_cleanup();
150  }
151  
152  module_init(ifs_init);
153  module_exit(ifs_exit);
154  
155  MODULE_LICENSE("GPL");
156  MODULE_DESCRIPTION("Intel In Field Scan (IFS) device");
157