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