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 pr_err("PTA_CMD_GET_DEVICES invoke function err: %x\n", 47 inv_arg.ret); 48 return -EINVAL; 49 } 50 51 *shm_size = param[0].u.memref.size; 52 53 return 0; 54 } 55 56 static void optee_release_device(struct device *dev) 57 { 58 struct tee_client_device *optee_device = to_tee_client_device(dev); 59 60 kfree(optee_device); 61 } 62 63 static ssize_t need_supplicant_show(struct device *dev, 64 struct device_attribute *attr, 65 char *buf) 66 { 67 return 0; 68 } 69 70 static DEVICE_ATTR_RO(need_supplicant); 71 72 static int optee_register_device(const uuid_t *device_uuid, u32 func) 73 { 74 struct tee_client_device *optee_device = NULL; 75 int rc; 76 77 optee_device = kzalloc(sizeof(*optee_device), GFP_KERNEL); 78 if (!optee_device) 79 return -ENOMEM; 80 81 optee_device->dev.bus = &tee_bus_type; 82 optee_device->dev.release = optee_release_device; 83 if (dev_set_name(&optee_device->dev, "optee-ta-%pUb", device_uuid)) { 84 kfree(optee_device); 85 return -ENOMEM; 86 } 87 uuid_copy(&optee_device->id.uuid, device_uuid); 88 89 rc = device_register(&optee_device->dev); 90 if (rc) { 91 pr_err("device registration failed, err: %d\n", rc); 92 put_device(&optee_device->dev); 93 return rc; 94 } 95 96 if (func == PTA_CMD_GET_DEVICES_SUPP) 97 device_create_file(&optee_device->dev, 98 &dev_attr_need_supplicant); 99 100 return 0; 101 } 102 103 static int __optee_enumerate_devices(u32 func) 104 { 105 const uuid_t pta_uuid = 106 UUID_INIT(0x7011a688, 0xddde, 0x4053, 107 0xa5, 0xa9, 0x7b, 0x3c, 0x4d, 0xdf, 0x13, 0xb8); 108 struct tee_ioctl_open_session_arg sess_arg; 109 struct tee_shm *device_shm = NULL; 110 const uuid_t *device_uuid = NULL; 111 struct tee_context *ctx = NULL; 112 u32 shm_size = 0, idx, num_devices = 0; 113 int rc; 114 115 memset(&sess_arg, 0, sizeof(sess_arg)); 116 117 /* Open context with OP-TEE driver */ 118 ctx = tee_client_open_context(NULL, optee_ctx_match, NULL, NULL); 119 if (IS_ERR(ctx)) 120 return -ENODEV; 121 122 /* Open session with device enumeration pseudo TA */ 123 export_uuid(sess_arg.uuid, &pta_uuid); 124 sess_arg.clnt_login = TEE_IOCTL_LOGIN_PUBLIC; 125 sess_arg.num_params = 0; 126 127 rc = tee_client_open_session(ctx, &sess_arg, NULL); 128 if ((rc < 0) || (sess_arg.ret != TEEC_SUCCESS)) { 129 /* Device enumeration pseudo TA not found */ 130 rc = 0; 131 goto out_ctx; 132 } 133 134 rc = get_devices(ctx, sess_arg.session, NULL, &shm_size, func); 135 if (rc < 0 || !shm_size) 136 goto out_sess; 137 138 device_shm = tee_shm_alloc_kernel_buf(ctx, shm_size); 139 if (IS_ERR(device_shm)) { 140 pr_err("tee_shm_alloc_kernel_buf failed\n"); 141 rc = PTR_ERR(device_shm); 142 goto out_sess; 143 } 144 145 rc = get_devices(ctx, sess_arg.session, device_shm, &shm_size, func); 146 if (rc < 0) 147 goto out_shm; 148 149 device_uuid = tee_shm_get_va(device_shm, 0); 150 if (IS_ERR(device_uuid)) { 151 pr_err("tee_shm_get_va failed\n"); 152 rc = PTR_ERR(device_uuid); 153 goto out_shm; 154 } 155 156 num_devices = shm_size / sizeof(uuid_t); 157 158 for (idx = 0; idx < num_devices; idx++) { 159 rc = optee_register_device(&device_uuid[idx], func); 160 if (rc) 161 goto out_shm; 162 } 163 164 out_shm: 165 tee_shm_free(device_shm); 166 out_sess: 167 tee_client_close_session(ctx, sess_arg.session); 168 out_ctx: 169 tee_client_close_context(ctx); 170 171 return rc; 172 } 173 174 int optee_enumerate_devices(u32 func) 175 { 176 return __optee_enumerate_devices(func); 177 } 178 179 static int __optee_unregister_device(struct device *dev, void *data) 180 { 181 if (!strncmp(dev_name(dev), "optee-ta", strlen("optee-ta"))) 182 device_unregister(dev); 183 184 return 0; 185 } 186 187 void optee_unregister_devices(void) 188 { 189 bus_for_each_dev(&tee_bus_type, NULL, NULL, 190 __optee_unregister_device); 191 } 192