1 | /* |
2 | * SPAPR TPM Proxy/Hypercall |
3 | * |
4 | * Copyright IBM Corp. 2019 |
5 | * |
6 | * Authors: |
7 | * Michael Roth <mdroth@linux.vnet.ibm.com> |
8 | * |
9 | * This work is licensed under the terms of the GNU GPL, version 2 or later. |
10 | * See the COPYING file in the top-level directory. |
11 | */ |
12 | |
13 | #include "qemu/osdep.h" |
14 | #include "qemu-common.h" |
15 | #include "qapi/error.h" |
16 | #include "qemu/error-report.h" |
17 | #include "sysemu/reset.h" |
18 | #include "cpu.h" |
19 | #include "hw/ppc/spapr.h" |
20 | #include "hw/qdev-properties.h" |
21 | #include "trace.h" |
22 | |
23 | #define TPM_SPAPR_BUFSIZE 4096 |
24 | |
25 | enum { |
26 | TPM_COMM_OP_EXECUTE = 1, |
27 | TPM_COMM_OP_CLOSE_SESSION = 2, |
28 | }; |
29 | |
30 | static void spapr_tpm_proxy_reset(void *opaque) |
31 | { |
32 | SpaprTpmProxy *tpm_proxy = SPAPR_TPM_PROXY(opaque); |
33 | |
34 | if (tpm_proxy->host_fd != -1) { |
35 | close(tpm_proxy->host_fd); |
36 | tpm_proxy->host_fd = -1; |
37 | } |
38 | } |
39 | |
40 | static ssize_t tpm_execute(SpaprTpmProxy *tpm_proxy, target_ulong *args) |
41 | { |
42 | uint64_t data_in = ppc64_phys_to_real(args[1]); |
43 | target_ulong data_in_size = args[2]; |
44 | uint64_t data_out = ppc64_phys_to_real(args[3]); |
45 | target_ulong data_out_size = args[4]; |
46 | uint8_t buf_in[TPM_SPAPR_BUFSIZE]; |
47 | uint8_t buf_out[TPM_SPAPR_BUFSIZE]; |
48 | ssize_t ret; |
49 | |
50 | trace_spapr_tpm_execute(data_in, data_in_size, data_out, data_out_size); |
51 | |
52 | if (data_in_size > TPM_SPAPR_BUFSIZE) { |
53 | error_report("invalid TPM input buffer size: " TARGET_FMT_lu, |
54 | data_in_size); |
55 | return H_P3; |
56 | } |
57 | |
58 | if (data_out_size < TPM_SPAPR_BUFSIZE) { |
59 | error_report("invalid TPM output buffer size: " TARGET_FMT_lu, |
60 | data_out_size); |
61 | return H_P5; |
62 | } |
63 | |
64 | if (tpm_proxy->host_fd == -1) { |
65 | tpm_proxy->host_fd = open(tpm_proxy->host_path, O_RDWR); |
66 | if (tpm_proxy->host_fd == -1) { |
67 | error_report("failed to open TPM device %s: %d" , |
68 | tpm_proxy->host_path, errno); |
69 | return H_RESOURCE; |
70 | } |
71 | } |
72 | |
73 | cpu_physical_memory_read(data_in, buf_in, data_in_size); |
74 | |
75 | do { |
76 | ret = write(tpm_proxy->host_fd, buf_in, data_in_size); |
77 | if (ret > 0) { |
78 | data_in_size -= ret; |
79 | } |
80 | } while ((ret >= 0 && data_in_size > 0) || (ret == -1 && errno == EINTR)); |
81 | |
82 | if (ret == -1) { |
83 | error_report("failed to write to TPM device %s: %d" , |
84 | tpm_proxy->host_path, errno); |
85 | return H_RESOURCE; |
86 | } |
87 | |
88 | do { |
89 | ret = read(tpm_proxy->host_fd, buf_out, data_out_size); |
90 | } while (ret == 0 || (ret == -1 && errno == EINTR)); |
91 | |
92 | if (ret == -1) { |
93 | error_report("failed to read from TPM device %s: %d" , |
94 | tpm_proxy->host_path, errno); |
95 | return H_RESOURCE; |
96 | } |
97 | |
98 | cpu_physical_memory_write(data_out, buf_out, ret); |
99 | args[0] = ret; |
100 | |
101 | return H_SUCCESS; |
102 | } |
103 | |
104 | static target_ulong h_tpm_comm(PowerPCCPU *cpu, |
105 | SpaprMachineState *spapr, |
106 | target_ulong opcode, |
107 | target_ulong *args) |
108 | { |
109 | target_ulong op = args[0]; |
110 | SpaprTpmProxy *tpm_proxy = spapr->tpm_proxy; |
111 | |
112 | if (!tpm_proxy) { |
113 | error_report("TPM proxy not available" ); |
114 | return H_FUNCTION; |
115 | } |
116 | |
117 | trace_spapr_h_tpm_comm(tpm_proxy->host_path ?: "null" , op); |
118 | |
119 | switch (op) { |
120 | case TPM_COMM_OP_EXECUTE: |
121 | return tpm_execute(tpm_proxy, args); |
122 | case TPM_COMM_OP_CLOSE_SESSION: |
123 | spapr_tpm_proxy_reset(tpm_proxy); |
124 | return H_SUCCESS; |
125 | default: |
126 | return H_PARAMETER; |
127 | } |
128 | } |
129 | |
130 | static void spapr_tpm_proxy_realize(DeviceState *d, Error **errp) |
131 | { |
132 | SpaprTpmProxy *tpm_proxy = SPAPR_TPM_PROXY(d); |
133 | |
134 | if (tpm_proxy->host_path == NULL) { |
135 | error_setg(errp, "must specify 'host-path' option for device" ); |
136 | return; |
137 | } |
138 | |
139 | tpm_proxy->host_fd = -1; |
140 | qemu_register_reset(spapr_tpm_proxy_reset, tpm_proxy); |
141 | } |
142 | |
143 | static void spapr_tpm_proxy_unrealize(DeviceState *d, Error **errp) |
144 | { |
145 | SpaprTpmProxy *tpm_proxy = SPAPR_TPM_PROXY(d); |
146 | |
147 | qemu_unregister_reset(spapr_tpm_proxy_reset, tpm_proxy); |
148 | } |
149 | |
150 | static Property spapr_tpm_proxy_properties[] = { |
151 | DEFINE_PROP_STRING("host-path" , SpaprTpmProxy, host_path), |
152 | DEFINE_PROP_END_OF_LIST(), |
153 | }; |
154 | |
155 | static void spapr_tpm_proxy_class_init(ObjectClass *k, void *data) |
156 | { |
157 | DeviceClass *dk = DEVICE_CLASS(k); |
158 | |
159 | dk->realize = spapr_tpm_proxy_realize; |
160 | dk->unrealize = spapr_tpm_proxy_unrealize; |
161 | dk->user_creatable = true; |
162 | dk->props = spapr_tpm_proxy_properties; |
163 | } |
164 | |
165 | static const TypeInfo spapr_tpm_proxy_info = { |
166 | .name = TYPE_SPAPR_TPM_PROXY, |
167 | .parent = TYPE_DEVICE, |
168 | .instance_size = sizeof(SpaprTpmProxy), |
169 | .class_init = spapr_tpm_proxy_class_init, |
170 | }; |
171 | |
172 | static void spapr_tpm_proxy_register_types(void) |
173 | { |
174 | type_register_static(&spapr_tpm_proxy_info); |
175 | spapr_register_hypercall(SVM_H_TPM_COMM, h_tpm_comm); |
176 | } |
177 | |
178 | type_init(spapr_tpm_proxy_register_types) |
179 | |