diff options
Diffstat (limited to 'security/smc/tf_crypto_rng.c')
| -rw-r--r-- | security/smc/tf_crypto_rng.c | 169 |
1 files changed, 169 insertions, 0 deletions
diff --git a/security/smc/tf_crypto_rng.c b/security/smc/tf_crypto_rng.c new file mode 100644 index 0000000..75f61eb --- /dev/null +++ b/security/smc/tf_crypto_rng.c @@ -0,0 +1,169 @@ +/** + * Copyright (c) 2011 Trusted Logic S.A. + * All Rights Reserved. + * + * This program is free software; you can redistribute it and/or + * modify it under the terms of the GNU General Public License + * version 2 as published by the Free Software Foundation. + * + * This program is distributed in the hope that it will be useful, + * but WITHOUT ANY WARRANTY; without even the implied warranty of + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the + * GNU General Public License for more details. + * + * You should have received a copy of the GNU General Public License + * along with this program; if not, write to the Free Software + * Foundation, Inc., 59 Temple Place, Suite 330, Boston, + * MA 02111-1307 USA + */ + +/** + * File : tf_crypto_rng.c + * Original-Author : Trusted Logic S.A. (Jeremie Corbier) + * Created : 07-12-2011 + */ + +#include <linux/types.h> +#include <linux/module.h> +#include <linux/slab.h> +#include <linux/hw_random.h> + +#include "tee_client_api.h" + +#define SERVICE_SYSTEM_UUID \ + { 0x56304b83, 0x5c4e, 0x4428, \ + { 0xb9, 0x9e, 0x60, 0x5c, 0x96, 0xae, 0x58, 0xd6 } } + +#define CKF_SERIAL_SESSION 0x00000004 + +#define SERVICE_SYSTEM_PKCS11_C_GENERATERANDOM_COMMAND_ID 0x00000039 +#define SERVICE_SYSTEM_PKCS11_C_OPEN_SESSION_COMMAND_ID 0x00000042 +#define SERVICE_SYSTEM_PKCS11_C_CLOSE_SESSION_COMMAND_ID 0x00000043 + +static struct hwrng tf_crypto_rng; + +static int tf_crypto_rng_read(struct hwrng *rng, void *data, size_t max, + bool wait) +{ + void *buf; + u32 cmd; + u32 crypto_session; + TEEC_Result ret; + TEEC_Operation op; + TEEC_Context teec_context; + TEEC_Session teec_session; + TEEC_UUID uuid = SERVICE_SYSTEM_UUID; + int err = 0; + + buf = kmalloc(max, GFP_KERNEL); + if (buf == NULL) + return -ENOMEM; + + ret = TEEC_InitializeContext(NULL, &teec_context); + if (ret != TEEC_SUCCESS) { + kfree(buf); + return -EFAULT; + } + + /* Call C_OpenSession */ + memset(&op, 0, sizeof(TEEC_Operation)); + + op.paramTypes = TEEC_PARAM_TYPES(TEEC_NONE, TEEC_NONE, TEEC_NONE, + TEEC_NONE); + + ret = TEEC_OpenSession(&teec_context, &teec_session, + &uuid, TEEC_LOGIN_PUBLIC, NULL, &op, NULL); + if (ret != TEEC_SUCCESS) { + kfree(buf); + TEEC_FinalizeContext(&teec_context); + return -EFAULT; + } + + memset(&op, 0, sizeof(TEEC_Operation)); + + op.paramTypes = TEEC_PARAM_TYPES(TEEC_VALUE_INOUT, TEEC_NONE, TEEC_NONE, + TEEC_NONE); + op.params[0].value.a = 0; + op.params[0].value.b = CKF_SERIAL_SESSION; + + cmd = SERVICE_SYSTEM_PKCS11_C_OPEN_SESSION_COMMAND_ID & 0x00007FFF; + + ret = TEEC_InvokeCommand(&teec_session, cmd, &op, NULL); + if (ret != TEEC_SUCCESS) { + printk(KERN_ERR "%s: TEEC_InvokeCommand returned 0x%08x\n", + __func__, ret); + err = -EFAULT; + goto exit; + } + + crypto_session = op.params[0].value.a; + + /* Call C_GenerateRandom */ + memset(&op, 0, sizeof(TEEC_Operation)); + + op.paramTypes = TEEC_PARAM_TYPES(TEEC_MEMREF_TEMP_OUTPUT, + TEEC_NONE, TEEC_NONE, TEEC_NONE); + op.params[0].tmpref.buffer = (uint8_t *) buf; + op.params[0].tmpref.size = (uint32_t) max; + + cmd = (crypto_session << 16) | + (SERVICE_SYSTEM_PKCS11_C_GENERATERANDOM_COMMAND_ID & 0x7fff); + + ret = TEEC_InvokeCommand(&teec_session, cmd, &op, NULL); + if (ret != TEEC_SUCCESS) { + printk(KERN_ERR "%s: TEEC_InvokeCommand returned 0x%08x\n", + __func__, ret); + err = -EFAULT; + } + + /* Call C_CloseSession */ + memset(&op, 0, sizeof(TEEC_Operation)); + + op.paramTypes = TEEC_PARAM_TYPES(TEEC_NONE, TEEC_NONE, TEEC_NONE, + TEEC_NONE); + + cmd = (crypto_session << 16) | + (SERVICE_SYSTEM_PKCS11_C_CLOSE_SESSION_COMMAND_ID & 0x7fff); + + ret = TEEC_InvokeCommand(&teec_session, cmd, &op, NULL); + if (ret != TEEC_SUCCESS) { + printk(KERN_ERR "%s: TEEC_InvokeCommand returned 0x%08x\n", + __func__, ret); + err = -EFAULT; + } + +exit: + TEEC_CloseSession(&teec_session); + TEEC_FinalizeContext(&teec_context); + + if (!err) + memcpy(data, buf, max); + + kfree(buf); + + if (err) + return err; + else + return max; +} + +static int __init tf_crypto_rng_init(void) +{ + memset(&tf_crypto_rng, 0, sizeof(struct hwrng)); + + tf_crypto_rng.name = "rng-smc"; + tf_crypto_rng.read = tf_crypto_rng_read; + + return hwrng_register(&tf_crypto_rng); +} +module_init(tf_crypto_rng_init); + +static void __exit tf_crypto_rng_exit(void) +{ + hwrng_unregister(&tf_crypto_rng); +} +module_exit(tf_crypto_rng_exit); + +MODULE_LICENSE("GPL"); +MODULE_AUTHOR("Jeremie Corbier <jeremie.corbier@trusted-logic.com>"); +MODULE_DESCRIPTION("OMAP4 TRNG driver."); |