1 // SPDX-License-Identifier: GPL-2.0 2 /* 3 * Copyright (C) 2019 Linaro Ltd. 4 */ 5 6 #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt 7 8 #include <linux/kernel.h> 9 #include <linux/slab.h> 10 #include <linux/tee_core.h> 11 #include <linux/uuid.h> 12 #include "optee_private.h" 13 14 static int optee_ctx_match(struct tee_ioctl_version_data *ver, const void *data) 15 { 16 if (ver->impl_id == TEE_IMPL_ID_OPTEE) 17 return 1; 18 else 19 return 0; 20 } 21 22 static int get_devices(struct tee_context *ctx, u32 session, 23 struct tee_shm *device_shm, u32 *shm_size, 24 u32 func) 25 { 26 int ret = 0; 27 struct tee_ioctl_invoke_arg inv_arg; 28 struct tee_param param[4]; 29 30 memset(&inv_arg, 0, sizeof(inv_arg)); 31 memset(¶m, 0, sizeof(param)); 32 33 inv_arg.func = func; 34 inv_arg.session = session; 35 inv_arg.num_params = 4; 36 37 /* Fill invoke cmd params */ 38 param[0].attr = TEE_IOCTL_PARAM_ATTR_TYPE_MEMREF_OUTPUT; 39 param[0].u.memref.shm = device_shm; 40 param[0].u.memref.size = *shm_size; 41 param[0].u.memref.shm_offs = 0; 42 43 ret = tee_client_invoke_func(ctx, &inv_arg, param); 44 if ((ret < 0) || ((inv_arg.ret != TEEC_SUCCESS) && 45 (inv_arg.ret != TEEC_ERROR_SHORT_BUFFER))) { 46 /* 47 * TEE_ERROR_STORAGE_NOT_AVAILABLE is returned when getting 48 * the list of device TAs that depends on RPMB but a usable 49 * RPMB device isn't found. 50 */ 51 if (inv_arg.ret == TEE_ERROR_STORAGE_NOT_AVAILABLE) 52 return -ENODEV; 53 pr_err("PTA_CMD_GET_DEVICES invoke function err: %x\n", 54 inv_arg.ret); 55 return -EINVAL; 56 } 57 58 *shm_size = param[0].u.memref.size; 59 60 return 0; 61 } 62 63 static void optee_release_device(struct device *dev) 64 { 65 struct tee_client_device *optee_device = to_tee_client_device(dev); 66 67 kfree(optee_device); 68 } 69 70 static ssize_t need_supplicant_show(struct device *dev, 71 struct device_attribute *attr, 72 char *buf) 73 { 74 return 0; 75 } 76 77 static DEVICE_ATTR_RO(need_supplicant); 78 79 static int optee_register_device(const uuid_t *device_uuid, u32 func) 80 { 81 struct tee_client_device *optee_device = NULL; 82 int rc; 83 84 optee_device = kzalloc(sizeof(*optee_device), GFP_KERNEL); 85 if (!optee_device) 86 return -ENOMEM; 87 88 optee_device->dev.bus = &tee_bus_type; 89 optee_device->dev.release = optee_release_device; 90 if (dev_set_name(&optee_device->dev, "optee-ta-%pUb", device_uuid)) { 91 kfree(optee_device); 92 return -ENOMEM; 93 } 94 uuid_copy(&optee_device->id.uuid, device_uuid); 95 96 rc = device_register(&optee_device->dev); 97 if (rc) { 98 pr_err("device registration failed, err: %d\n", rc); 99 put_device(&optee_device->dev); 100 return rc; 101 } 102 103 if (func == PTA_CMD_GET_DEVICES_SUPP) 104 device_create_file(&optee_device->dev, 105 &dev_attr_need_supplicant); 106 107 return 0; 108 } 109 110 static int __optee_enumerate_devices(u32 func) 111 { 112 const uuid_t pta_uuid = 113 UUID_INIT(0x7011a688, 0xddde, 0x4053, 114 0xa5, 0xa9, 0x7b, 0x3c, 0x4d, 0xdf, 0x13, 0xb8); 115 struct tee_ioctl_open_session_arg sess_arg; 116 struct tee_shm *device_shm = NULL; 117 const uuid_t *device_uuid = NULL; 118 struct tee_context *ctx = NULL; 119 u32 shm_size = 0, idx, num_devices = 0; 120 int rc; 121 122 memset(&sess_arg, 0, sizeof(sess_arg)); 123 124 /* Open context with OP-TEE driver */ 125 ctx = tee_client_open_context(NULL, optee_ctx_match, NULL, NULL); 126 if (IS_ERR(ctx)) 127 return -ENODEV; 128 129 /* Open session with device enumeration pseudo TA */ 130 export_uuid(sess_arg.uuid, &pta_uuid); 131 sess_arg.clnt_login = TEE_IOCTL_LOGIN_PUBLIC; 132 sess_arg.num_params = 0; 133 134 rc = tee_client_open_session(ctx, &sess_arg, NULL); 135 if ((rc < 0) || (sess_arg.ret != TEEC_SUCCESS)) { 136 /* Device enumeration pseudo TA not found */ 137 rc = 0; 138 goto out_ctx; 139 } 140 141 rc = get_devices(ctx, sess_arg.session, NULL, &shm_size, func); 142 if (rc < 0 || !shm_size) 143 goto out_sess; 144 145 device_shm = tee_shm_alloc_kernel_buf(ctx, shm_size); 146 if (IS_ERR(device_shm)) { 147 pr_err("tee_shm_alloc_kernel_buf failed\n"); 148 rc = PTR_ERR(device_shm); 149 goto out_sess; 150 } 151 152 rc = get_devices(ctx, sess_arg.session, device_shm, &shm_size, func); 153 if (rc < 0) 154 goto out_shm; 155 156 device_uuid = tee_shm_get_va(device_shm, 0); 157 if (IS_ERR(device_uuid)) { 158 pr_err("tee_shm_get_va failed\n"); 159 rc = PTR_ERR(device_uuid); 160 goto out_shm; 161 } 162 163 num_devices = shm_size / sizeof(uuid_t); 164 165 for (idx = 0; idx < num_devices; idx++) { 166 rc = optee_register_device(&device_uuid[idx], func); 167 if (rc) 168 goto out_shm; 169 } 170 171 out_shm: 172 tee_shm_free(device_shm); 173 out_sess: 174 tee_client_close_session(ctx, sess_arg.session); 175 out_ctx: 176 tee_client_close_context(ctx); 177 178 return rc; 179 } 180 181 int optee_enumerate_devices(u32 func) 182 { 183 return __optee_enumerate_devices(func); 184 } 185 186 static int __optee_unregister_device(struct device *dev, void *data) 187 { 188 if (!strncmp(dev_name(dev), "optee-ta", strlen("optee-ta"))) 189 device_unregister(dev); 190 191 return 0; 192 } 193 194 void optee_unregister_devices(void) 195 { 196 bus_for_each_dev(&tee_bus_type, NULL, NULL, 197 __optee_unregister_device); 198 } 199