From 6a488d9cf6428aaf117d57413c019f3e073914eb Mon Sep 17 00:00:00 2001 From: Brijesh Singh Date: Mon, 4 Dec 2017 10:57:29 -0600 Subject: [PATCH 25/95] crypto: ccp: Implement SEV_FACTORY_RESET ioctl command MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit The SEV_FACTORY_RESET command can be used by the platform owner to reset the non-volatile SEV related data. The command is defined in SEV spec section 5.4 Cc: Paolo Bonzini Cc: "Radim Krčmář" Cc: Borislav Petkov Cc: Herbert Xu Cc: Gary Hook Cc: Tom Lendacky Cc: linux-crypto@vger.kernel.org Cc: kvm@vger.kernel.org Cc: linux-kernel@vger.kernel.org Improvements-by: Borislav Petkov Signed-off-by: Brijesh Singh Signed-off-by: Sudheesh Mavila --- drivers/crypto/ccp/psp-dev.c | 77 +++++++++++++++++++++++++++++++++++++++++++- 1 file changed, 76 insertions(+), 1 deletion(-) diff --git a/drivers/crypto/ccp/psp-dev.c b/drivers/crypto/ccp/psp-dev.c index 9915a6c..b49583a4 100644 --- a/drivers/crypto/ccp/psp-dev.c +++ b/drivers/crypto/ccp/psp-dev.c @@ -232,9 +232,84 @@ static int sev_platform_shutdown(int *error) return rc; } +static int sev_get_platform_state(int *state, int *error) +{ + int rc; + + rc = __sev_do_cmd_locked(SEV_CMD_PLATFORM_STATUS, + &psp_master->status_cmd_buf, error); + if (rc) + return rc; + + *state = psp_master->status_cmd_buf.state; + return rc; +} + +static int sev_ioctl_do_reset(struct sev_issue_cmd *argp) +{ + int state, rc; + + /* + * The SEV spec requires that FACTORY_RESET must be issued in + * UNINIT state. Before we go further lets check if any guest is + * active. + * + * If FW is in WORKING state then deny the request otherwise issue + * SHUTDOWN command do INIT -> UNINIT before issuing the FACTORY_RESET. + * + */ + rc = sev_get_platform_state(&state, &argp->error); + if (rc) + return rc; + + if (state == SEV_STATE_WORKING) + return -EBUSY; + + if (state == SEV_STATE_INIT) { + rc = __sev_platform_shutdown_locked(&argp->error); + if (rc) + return rc; + } + + return __sev_do_cmd_locked(SEV_CMD_FACTORY_RESET, 0, &argp->error); +} + static long sev_ioctl(struct file *file, unsigned int ioctl, unsigned long arg) { - return -ENOTTY; + void __user *argp = (void __user *)arg; + struct sev_issue_cmd input; + int ret = -EFAULT; + + if (!psp_master) + return -ENODEV; + + if (ioctl != SEV_ISSUE_CMD) + return -EINVAL; + + if (copy_from_user(&input, argp, sizeof(struct sev_issue_cmd))) + return -EFAULT; + + if (input.cmd > SEV_MAX) + return -EINVAL; + + mutex_lock(&sev_cmd_mutex); + + switch (input.cmd) { + + case SEV_FACTORY_RESET: + ret = sev_ioctl_do_reset(&input); + break; + default: + ret = -EINVAL; + goto out; + } + + if (copy_to_user(argp, &input, sizeof(struct sev_issue_cmd))) + ret = -EFAULT; +out: + mutex_unlock(&sev_cmd_mutex); + + return ret; } static const struct file_operations sev_fops = { -- 2.7.4