aboutsummaryrefslogtreecommitdiff
path: root/hw/ppc/spapr_tpm_proxy.c
blob: e10af35a1850444745390002a1440625b8dc66f0 (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
/*
 * SPAPR TPM Proxy/Hypercall
 *
 * Copyright IBM Corp. 2019
 *
 * Authors:
 *  Michael Roth      <mdroth@linux.vnet.ibm.com>
 *
 * This work is licensed under the terms of the GNU GPL, version 2 or later.
 * See the COPYING file in the top-level directory.
 */

#include "qemu/osdep.h"
#include "qapi/error.h"
#include "qemu/error-report.h"
#include "sysemu/reset.h"
#include "hw/ppc/spapr.h"
#include "hw/qdev-properties.h"
#include "trace.h"

#define TPM_SPAPR_BUFSIZE 4096

enum {
    TPM_COMM_OP_EXECUTE = 1,
    TPM_COMM_OP_CLOSE_SESSION = 2,
};

static void spapr_tpm_proxy_reset(void *opaque)
{
    SpaprTpmProxy *tpm_proxy = SPAPR_TPM_PROXY(opaque);

    if (tpm_proxy->host_fd != -1) {
        close(tpm_proxy->host_fd);
        tpm_proxy->host_fd = -1;
    }
}

static ssize_t tpm_execute(SpaprTpmProxy *tpm_proxy, target_ulong *args)
{
    uint64_t data_in = ppc64_phys_to_real(args[1]);
    target_ulong data_in_size = args[2];
    uint64_t data_out = ppc64_phys_to_real(args[3]);
    target_ulong data_out_size = args[4];
    uint8_t buf_in[TPM_SPAPR_BUFSIZE];
    uint8_t buf_out[TPM_SPAPR_BUFSIZE];
    ssize_t ret;

    trace_spapr_tpm_execute(data_in, data_in_size, data_out, data_out_size);

    if (data_in_size > TPM_SPAPR_BUFSIZE) {
        error_report("invalid TPM input buffer size: " TARGET_FMT_lu,
                     data_in_size);
        return H_P3;
    }

    if (data_out_size < TPM_SPAPR_BUFSIZE) {
        error_report("invalid TPM output buffer size: " TARGET_FMT_lu,
                     data_out_size);
        return H_P5;
    }

    if (tpm_proxy->host_fd == -1) {
        tpm_proxy->host_fd = open(tpm_proxy->host_path, O_RDWR);
        if (tpm_proxy->host_fd == -1) {
            error_report("failed to open TPM device %s: %d",
                         tpm_proxy->host_path, errno);
            return H_RESOURCE;
        }
    }

    cpu_physical_memory_read(data_in, buf_in, data_in_size);

    do {
        ret = write(tpm_proxy->host_fd, buf_in, data_in_size);
        if (ret > 0) {
            data_in_size -= ret;
        }
    } while ((ret >= 0 && data_in_size > 0) || (ret == -1 && errno == EINTR));

    if (ret == -1) {
        error_report("failed to write to TPM device %s: %d",
                     tpm_proxy->host_path, errno);
        return H_RESOURCE;
    }

    do {
        ret = read(tpm_proxy->host_fd, buf_out, data_out_size);
    } while (ret == 0 || (ret == -1 && errno == EINTR));

    if (ret == -1) {
        error_report("failed to read from TPM device %s: %d",
                     tpm_proxy->host_path, errno);
        return H_RESOURCE;
    }

    cpu_physical_memory_write(data_out, buf_out, ret);
    args[0] = ret;

    return H_SUCCESS;
}

static target_ulong h_tpm_comm(PowerPCCPU *cpu,
                               SpaprMachineState *spapr,
                               target_ulong opcode,
                               target_ulong *args)
{
    target_ulong op = args[0];
    SpaprTpmProxy *tpm_proxy = spapr->tpm_proxy;

    if (!tpm_proxy) {
        error_report("TPM proxy not available");
        return H_FUNCTION;
    }

    trace_spapr_h_tpm_comm(tpm_proxy->host_path, op);

    switch (op) {
    case TPM_COMM_OP_EXECUTE:
        return tpm_execute(tpm_proxy, args);
    case TPM_COMM_OP_CLOSE_SESSION:
        spapr_tpm_proxy_reset(tpm_proxy);
        return H_SUCCESS;
    default:
        return H_PARAMETER;
    }
}

static void spapr_tpm_proxy_realize(DeviceState *d, Error **errp)
{
    SpaprTpmProxy *tpm_proxy = SPAPR_TPM_PROXY(d);

    if (tpm_proxy->host_path == NULL) {
        error_setg(errp, "must specify 'host-path' option for device");
        return;
    }

    tpm_proxy->host_fd = -1;
    qemu_register_reset(spapr_tpm_proxy_reset, tpm_proxy);
}

static void spapr_tpm_proxy_unrealize(DeviceState *d)
{
    SpaprTpmProxy *tpm_proxy = SPAPR_TPM_PROXY(d);

    qemu_unregister_reset(spapr_tpm_proxy_reset, tpm_proxy);
}

static Property spapr_tpm_proxy_properties[] = {
    DEFINE_PROP_STRING("host-path", SpaprTpmProxy, host_path),
    DEFINE_PROP_END_OF_LIST(),
};

static void spapr_tpm_proxy_class_init(ObjectClass *k, void *data)
{
    DeviceClass *dk = DEVICE_CLASS(k);

    dk->realize = spapr_tpm_proxy_realize;
    dk->unrealize = spapr_tpm_proxy_unrealize;
    dk->user_creatable = true;
    device_class_set_props(dk, spapr_tpm_proxy_properties);
}

static const TypeInfo spapr_tpm_proxy_info = {
    .name          = TYPE_SPAPR_TPM_PROXY,
    .parent        = TYPE_DEVICE,
    .instance_size = sizeof(SpaprTpmProxy),
    .class_init    = spapr_tpm_proxy_class_init,
};

static void spapr_tpm_proxy_register_types(void)
{
    type_register_static(&spapr_tpm_proxy_info);
    spapr_register_hypercall(SVM_H_TPM_COMM, h_tpm_comm);
}

type_init(spapr_tpm_proxy_register_types)