freebsd-dev/sys/amd64/sgx/sgx.c
Jeff Roberson 0f9e06e18b Fix a few places that free a page from an object without busy held. This is
tightening constraints on busy as a precursor to lockless page lookup and
should largely be a NOP for these cases.

Reviewed by:	alc, kib, markj
Differential Revision:	https://reviews.freebsd.org/D22611
2019-12-02 22:42:05 +00:00

1223 lines
28 KiB
C

/*-
* Copyright (c) 2017 Ruslan Bukin <br@bsdpad.com>
* All rights reserved.
*
* This software was developed by BAE Systems, the University of Cambridge
* Computer Laboratory, and Memorial University under DARPA/AFRL contract
* FA8650-15-C-7558 ("CADETS"), as part of the DARPA Transparent Computing
* (TC) research program.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
*
* THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
* ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
* ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
* FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
* DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
* OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
* HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
* LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
* OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
* SUCH DAMAGE.
*/
/*
* Design overview.
*
* The driver provides character device for mmap(2) and ioctl(2) system calls
* allowing user to manage isolated compartments ("enclaves") in user VA space.
*
* The driver duties is EPC pages management, enclave management, user data
* validation.
*
* This driver requires Intel SGX support from hardware.
*
* /dev/sgx:
* .mmap:
* sgx_mmap_single() allocates VM object with following pager
* operations:
* a) sgx_pg_ctor():
* VM object constructor does nothing
* b) sgx_pg_dtor():
* VM object destructor destroys the SGX enclave associated
* with the object: it frees all the EPC pages allocated for
* enclave and removes the enclave.
* c) sgx_pg_fault():
* VM object fault handler does nothing
*
* .ioctl:
* sgx_ioctl():
* a) SGX_IOC_ENCLAVE_CREATE
* Adds Enclave SECS page: initial step of enclave creation.
* b) SGX_IOC_ENCLAVE_ADD_PAGE
* Adds TCS, REG pages to the enclave.
* c) SGX_IOC_ENCLAVE_INIT
* Finalizes enclave creation.
*
* Enclave lifecycle:
* .-- ECREATE -- Add SECS page
* Kernel | EADD -- Add TCS, REG pages
* space | EEXTEND -- Measure the page (take unique hash)
* ENCLS | EPA -- Allocate version array page
* '-- EINIT -- Finalize enclave creation
* User .-- EENTER -- Go to entry point of enclave
* space | EEXIT -- Exit back to main application
* ENCLU '-- ERESUME -- Resume enclave execution (e.g. after exception)
*
* Enclave lifecycle from driver point of view:
* 1) User calls mmap() on /dev/sgx: we allocate a VM object
* 2) User calls ioctl SGX_IOC_ENCLAVE_CREATE: we look for the VM object
* associated with user process created on step 1, create SECS physical
* page and store it in enclave's VM object queue by special index
* SGX_SECS_VM_OBJECT_INDEX.
* 3) User calls ioctl SGX_IOC_ENCLAVE_ADD_PAGE: we look for enclave created
* on step 2, create TCS or REG physical page and map it to specified by
* user address of enclave VM object.
* 4) User finalizes enclave creation with ioctl SGX_IOC_ENCLAVE_INIT call.
* 5) User can freely enter to and exit from enclave using ENCLU instructions
* from userspace: the driver does nothing here.
* 6) User proceed munmap(2) system call (or the process with enclave dies):
* we destroy the enclave associated with the object.
*
* EPC page types and their indexes in VM object queue:
* - PT_SECS index is special and equals SGX_SECS_VM_OBJECT_INDEX (-1);
* - PT_TCS and PT_REG indexes are specified by user in addr field of ioctl
* request data and determined as follows:
* pidx = OFF_TO_IDX(addp->addr - vmh->base);
* - PT_VA index is special, created for PT_REG, PT_TCS and PT_SECS pages
* and determined by formula:
* va_page_idx = - SGX_VA_PAGES_OFFS - (page_idx / SGX_VA_PAGE_SLOTS);
* PT_VA page can hold versions of up to 512 pages, and slot for each
* page in PT_VA page is determined as follows:
* va_slot_idx = page_idx % SGX_VA_PAGE_SLOTS;
* - PT_TRIM is unused.
*
* Locking:
* SGX ENCLS set of instructions have limitations on concurrency:
* some instructions can't be executed same time on different CPUs.
* We use sc->mtx_encls lock around them to prevent concurrent execution.
* sc->mtx lock is used to manage list of created enclaves and the state of
* SGX driver.
*
* Eviction of EPC pages:
* Eviction support is not implemented in this driver, however the driver
* manages VA (version array) pages: it allocates a VA slot for each EPC
* page. This will be required for eviction support in future.
* VA pages and slots are currently unused.
*
* Intel® 64 and IA-32 Architectures Software Developer's Manual
* https://software.intel.com/en-us/articles/intel-sdm
*/
#include <sys/cdefs.h>
__FBSDID("$FreeBSD$");
#include <sys/param.h>
#include <sys/systm.h>
#include <sys/ioccom.h>
#include <sys/malloc.h>
#include <sys/kernel.h>
#include <sys/lock.h>
#include <sys/mutex.h>
#include <sys/rwlock.h>
#include <sys/conf.h>
#include <sys/module.h>
#include <sys/proc.h>
#include <sys/vmem.h>
#include <sys/vmmeter.h>
#include <vm/vm.h>
#include <vm/vm_param.h>
#include <vm/vm_extern.h>
#include <vm/vm_kern.h>
#include <vm/vm_page.h>
#include <vm/vm_map.h>
#include <vm/vm_object.h>
#include <vm/vm_pager.h>
#include <vm/vm_phys.h>
#include <vm/vm_radix.h>
#include <vm/pmap.h>
#include <machine/md_var.h>
#include <machine/specialreg.h>
#include <machine/cpufunc.h>
#include <machine/sgx.h>
#include <machine/sgxreg.h>
#include <amd64/sgx/sgxvar.h>
#define SGX_DEBUG
#undef SGX_DEBUG
#ifdef SGX_DEBUG
#define dprintf(fmt, ...) printf(fmt, ##__VA_ARGS__)
#else
#define dprintf(fmt, ...)
#endif
static struct cdev_pager_ops sgx_pg_ops;
struct sgx_softc sgx_sc;
static int
sgx_get_epc_page(struct sgx_softc *sc, struct epc_page **epc)
{
vmem_addr_t addr;
int i;
if (vmem_alloc(sc->vmem_epc, PAGE_SIZE, M_FIRSTFIT | M_NOWAIT,
&addr) == 0) {
i = (addr - sc->epc_base) / PAGE_SIZE;
*epc = &sc->epc_pages[i];
return (0);
}
return (ENOMEM);
}
static void
sgx_put_epc_page(struct sgx_softc *sc, struct epc_page *epc)
{
vmem_addr_t addr;
if (epc == NULL)
return;
addr = (epc->index * PAGE_SIZE) + sc->epc_base;
vmem_free(sc->vmem_epc, addr, PAGE_SIZE);
}
static int
sgx_va_slot_init_by_index(struct sgx_softc *sc, vm_object_t object,
uint64_t idx)
{
struct epc_page *epc;
vm_page_t page;
vm_page_t p;
int ret;
VM_OBJECT_ASSERT_WLOCKED(object);
p = vm_page_lookup(object, idx);
if (p == NULL) {
ret = sgx_get_epc_page(sc, &epc);
if (ret) {
dprintf("%s: No free EPC pages available.\n",
__func__);
return (ret);
}
mtx_lock(&sc->mtx_encls);
sgx_epa((void *)epc->base);
mtx_unlock(&sc->mtx_encls);
page = PHYS_TO_VM_PAGE(epc->phys);
page->valid = VM_PAGE_BITS_ALL;
vm_page_insert(page, object, idx);
}
return (0);
}
static int
sgx_va_slot_init(struct sgx_softc *sc,
struct sgx_enclave *enclave,
uint64_t addr)
{
vm_pindex_t pidx;
uint64_t va_page_idx;
uint64_t idx;
vm_object_t object;
int va_slot;
int ret;
object = enclave->object;
VM_OBJECT_ASSERT_WLOCKED(object);
pidx = OFF_TO_IDX(addr);
va_slot = pidx % SGX_VA_PAGE_SLOTS;
va_page_idx = pidx / SGX_VA_PAGE_SLOTS;
idx = - SGX_VA_PAGES_OFFS - va_page_idx;
ret = sgx_va_slot_init_by_index(sc, object, idx);
return (ret);
}
static int
sgx_mem_find(struct sgx_softc *sc, uint64_t addr,
vm_map_entry_t *entry0, vm_object_t *object0)
{
vm_map_t map;
vm_map_entry_t entry;
vm_object_t object;
map = &curproc->p_vmspace->vm_map;
vm_map_lock_read(map);
if (!vm_map_lookup_entry(map, addr, &entry)) {
vm_map_unlock_read(map);
dprintf("%s: Can't find enclave.\n", __func__);
return (EINVAL);
}
object = entry->object.vm_object;
if (object == NULL || object->handle == NULL) {
vm_map_unlock_read(map);
return (EINVAL);
}
if (object->type != OBJT_MGTDEVICE ||
object->un_pager.devp.ops != &sgx_pg_ops) {
vm_map_unlock_read(map);
return (EINVAL);
}
vm_object_reference(object);
*object0 = object;
*entry0 = entry;
vm_map_unlock_read(map);
return (0);
}
static int
sgx_enclave_find(struct sgx_softc *sc, uint64_t addr,
struct sgx_enclave **encl)
{
struct sgx_vm_handle *vmh;
struct sgx_enclave *enclave;
vm_map_entry_t entry;
vm_object_t object;
int ret;
ret = sgx_mem_find(sc, addr, &entry, &object);
if (ret)
return (ret);
vmh = object->handle;
if (vmh == NULL) {
vm_object_deallocate(object);
return (EINVAL);
}
enclave = vmh->enclave;
if (enclave == NULL || enclave->object == NULL) {
vm_object_deallocate(object);
return (EINVAL);
}
*encl = enclave;
return (0);
}
static int
sgx_enclave_alloc(struct sgx_softc *sc, struct secs *secs,
struct sgx_enclave **enclave0)
{
struct sgx_enclave *enclave;
enclave = malloc(sizeof(struct sgx_enclave),
M_SGX, M_WAITOK | M_ZERO);
enclave->base = secs->base;
enclave->size = secs->size;
*enclave0 = enclave;
return (0);
}
static void
sgx_epc_page_remove(struct sgx_softc *sc,
struct epc_page *epc)
{
mtx_lock(&sc->mtx_encls);
sgx_eremove((void *)epc->base);
mtx_unlock(&sc->mtx_encls);
}
static void
sgx_page_remove(struct sgx_softc *sc, vm_page_t p)
{
struct epc_page *epc;
vm_paddr_t pa;
uint64_t offs;
(void)vm_page_remove(p);
dprintf("%s: p->pidx %ld\n", __func__, p->pindex);
pa = VM_PAGE_TO_PHYS(p);
epc = &sc->epc_pages[0];
offs = (pa - epc->phys) / PAGE_SIZE;
epc = &sc->epc_pages[offs];
sgx_epc_page_remove(sc, epc);
sgx_put_epc_page(sc, epc);
}
static void
sgx_enclave_remove(struct sgx_softc *sc,
struct sgx_enclave *enclave)
{
vm_object_t object;
vm_page_t p, p_secs, p_next;
mtx_lock(&sc->mtx);
TAILQ_REMOVE(&sc->enclaves, enclave, next);
mtx_unlock(&sc->mtx);
object = enclave->object;
VM_OBJECT_WLOCK(object);
/*
* First remove all the pages except SECS,
* then remove SECS page.
*/
restart:
TAILQ_FOREACH_SAFE(p, &object->memq, listq, p_next) {
if (p->pindex == SGX_SECS_VM_OBJECT_INDEX)
continue;
if (vm_page_busy_acquire(p, VM_ALLOC_WAITFAIL) == 0)
goto restart;
sgx_page_remove(sc, p);
}
p_secs = vm_page_grab(object, SGX_SECS_VM_OBJECT_INDEX,
VM_ALLOC_NOCREAT);
/* Now remove SECS page */
if (p_secs != NULL)
sgx_page_remove(sc, p_secs);
KASSERT(TAILQ_EMPTY(&object->memq) == 1, ("not empty"));
KASSERT(object->resident_page_count == 0, ("count"));
VM_OBJECT_WUNLOCK(object);
}
static int
sgx_measure_page(struct sgx_softc *sc, struct epc_page *secs,
struct epc_page *epc, uint16_t mrmask)
{
int i, j;
int ret;
mtx_lock(&sc->mtx_encls);
for (i = 0, j = 1; i < PAGE_SIZE; i += 0x100, j <<= 1) {
if (!(j & mrmask))
continue;
ret = sgx_eextend((void *)secs->base,
(void *)(epc->base + i));
if (ret == SGX_EFAULT) {
mtx_unlock(&sc->mtx_encls);
return (ret);
}
}
mtx_unlock(&sc->mtx_encls);
return (0);
}
static int
sgx_secs_validate(struct sgx_softc *sc, struct secs *secs)
{
struct secs_attr *attr;
int i;
if (secs->size == 0)
return (EINVAL);
/* BASEADDR must be naturally aligned on an SECS.SIZE boundary. */
if (secs->base & (secs->size - 1))
return (EINVAL);
/* SECS.SIZE must be at least 2 pages. */
if (secs->size < 2 * PAGE_SIZE)
return (EINVAL);
if ((secs->size & (secs->size - 1)) != 0)
return (EINVAL);
attr = &secs->attributes;
if (attr->reserved1 != 0 ||
attr->reserved2 != 0 ||
attr->reserved3 != 0)
return (EINVAL);
for (i = 0; i < SECS_ATTR_RSV4_SIZE; i++)
if (attr->reserved4[i])
return (EINVAL);
/*
* Intel® Software Guard Extensions Programming Reference
* 6.7.2 Relevant Fields in Various Data Structures
* 6.7.2.1 SECS.ATTRIBUTES.XFRM
* XFRM[1:0] must be set to 0x3.
*/
if ((attr->xfrm & 0x3) != 0x3)
return (EINVAL);
if (!attr->mode64bit)
return (EINVAL);
if (secs->size > sc->enclave_size_max)
return (EINVAL);
for (i = 0; i < SECS_RSV1_SIZE; i++)
if (secs->reserved1[i])
return (EINVAL);
for (i = 0; i < SECS_RSV2_SIZE; i++)
if (secs->reserved2[i])
return (EINVAL);
for (i = 0; i < SECS_RSV3_SIZE; i++)
if (secs->reserved3[i])
return (EINVAL);
for (i = 0; i < SECS_RSV4_SIZE; i++)
if (secs->reserved4[i])
return (EINVAL);
return (0);
}
static int
sgx_tcs_validate(struct tcs *tcs)
{
int i;
if ((tcs->flags) ||
(tcs->ossa & (PAGE_SIZE - 1)) ||
(tcs->ofsbasgx & (PAGE_SIZE - 1)) ||
(tcs->ogsbasgx & (PAGE_SIZE - 1)) ||
((tcs->fslimit & 0xfff) != 0xfff) ||
((tcs->gslimit & 0xfff) != 0xfff))
return (EINVAL);
for (i = 0; i < nitems(tcs->reserved3); i++)
if (tcs->reserved3[i])
return (EINVAL);
return (0);
}
static void
sgx_tcs_dump(struct sgx_softc *sc, struct tcs *t)
{
dprintf("t->flags %lx\n", t->flags);
dprintf("t->ossa %lx\n", t->ossa);
dprintf("t->cssa %x\n", t->cssa);
dprintf("t->nssa %x\n", t->nssa);
dprintf("t->oentry %lx\n", t->oentry);
dprintf("t->ofsbasgx %lx\n", t->ofsbasgx);
dprintf("t->ogsbasgx %lx\n", t->ogsbasgx);
dprintf("t->fslimit %x\n", t->fslimit);
dprintf("t->gslimit %x\n", t->gslimit);
}
static int
sgx_pg_ctor(void *handle, vm_ooffset_t size, vm_prot_t prot,
vm_ooffset_t foff, struct ucred *cred, u_short *color)
{
struct sgx_vm_handle *vmh;
vmh = handle;
if (vmh == NULL) {
dprintf("%s: vmh not found.\n", __func__);
return (0);
}
dprintf("%s: vmh->base %lx foff 0x%lx size 0x%lx\n",
__func__, vmh->base, foff, size);
return (0);
}
static void
sgx_pg_dtor(void *handle)
{
struct sgx_vm_handle *vmh;
struct sgx_softc *sc;
vmh = handle;
if (vmh == NULL) {
dprintf("%s: vmh not found.\n", __func__);
return;
}
sc = vmh->sc;
if (sc == NULL) {
dprintf("%s: sc is NULL\n", __func__);
return;
}
if (vmh->enclave == NULL) {
dprintf("%s: Enclave not found.\n", __func__);
return;
}
sgx_enclave_remove(sc, vmh->enclave);
free(vmh->enclave, M_SGX);
free(vmh, M_SGX);
}
static int
sgx_pg_fault(vm_object_t object, vm_ooffset_t offset,
int prot, vm_page_t *mres)
{
/*
* The purpose of this trivial handler is to handle the race
* when user tries to access mmaped region before or during
* enclave creation ioctl calls.
*/
dprintf("%s: offset 0x%lx\n", __func__, offset);
return (VM_PAGER_FAIL);
}
static struct cdev_pager_ops sgx_pg_ops = {
.cdev_pg_ctor = sgx_pg_ctor,
.cdev_pg_dtor = sgx_pg_dtor,
.cdev_pg_fault = sgx_pg_fault,
};
static void
sgx_insert_epc_page_by_index(vm_page_t page, vm_object_t object,
vm_pindex_t pidx)
{
VM_OBJECT_ASSERT_WLOCKED(object);
page->valid = VM_PAGE_BITS_ALL;
vm_page_insert(page, object, pidx);
}
static void
sgx_insert_epc_page(struct sgx_enclave *enclave,
struct epc_page *epc, uint64_t addr)
{
vm_pindex_t pidx;
vm_page_t page;
VM_OBJECT_ASSERT_WLOCKED(enclave->object);
pidx = OFF_TO_IDX(addr);
page = PHYS_TO_VM_PAGE(epc->phys);
sgx_insert_epc_page_by_index(page, enclave->object, pidx);
}
static int
sgx_ioctl_create(struct sgx_softc *sc, struct sgx_enclave_create *param)
{
struct sgx_vm_handle *vmh;
vm_map_entry_t entry;
vm_page_t p;
struct page_info pginfo;
struct secinfo secinfo;
struct sgx_enclave *enclave;
struct epc_page *epc;
struct secs *secs;
vm_object_t object;
vm_page_t page;
int ret;
epc = NULL;
secs = NULL;
enclave = NULL;
object = NULL;
/* SGX Enclave Control Structure (SECS) */
secs = malloc(PAGE_SIZE, M_SGX, M_WAITOK | M_ZERO);
ret = copyin((void *)param->src, secs, sizeof(struct secs));
if (ret) {
dprintf("%s: Can't copy SECS.\n", __func__);
goto error;
}
ret = sgx_secs_validate(sc, secs);
if (ret) {
dprintf("%s: SECS validation failed.\n", __func__);
goto error;
}
ret = sgx_mem_find(sc, secs->base, &entry, &object);
if (ret) {
dprintf("%s: Can't find vm_map.\n", __func__);
goto error;
}
vmh = object->handle;
if (!vmh) {
dprintf("%s: Can't find vmh.\n", __func__);
ret = ENXIO;
goto error;
}
dprintf("%s: entry start %lx offset %lx\n",
__func__, entry->start, entry->offset);
vmh->base = (entry->start - entry->offset);
ret = sgx_enclave_alloc(sc, secs, &enclave);
if (ret) {
dprintf("%s: Can't alloc enclave.\n", __func__);
goto error;
}
enclave->object = object;
enclave->vmh = vmh;
memset(&secinfo, 0, sizeof(struct secinfo));
memset(&pginfo, 0, sizeof(struct page_info));
pginfo.linaddr = 0;
pginfo.srcpge = (uint64_t)secs;
pginfo.secinfo = &secinfo;
pginfo.secs = 0;
ret = sgx_get_epc_page(sc, &epc);
if (ret) {
dprintf("%s: Failed to get free epc page.\n", __func__);
goto error;
}
enclave->secs_epc_page = epc;
VM_OBJECT_WLOCK(object);
p = vm_page_lookup(object, SGX_SECS_VM_OBJECT_INDEX);
if (p) {
VM_OBJECT_WUNLOCK(object);
/* SECS page already added. */
ret = ENXIO;
goto error;
}
ret = sgx_va_slot_init_by_index(sc, object,
- SGX_VA_PAGES_OFFS - SGX_SECS_VM_OBJECT_INDEX);
if (ret) {
VM_OBJECT_WUNLOCK(object);
dprintf("%s: Can't init va slot.\n", __func__);
goto error;
}
mtx_lock(&sc->mtx);
if ((sc->state & SGX_STATE_RUNNING) == 0) {
mtx_unlock(&sc->mtx);
/* Remove VA page that was just created for SECS page. */
p = vm_page_grab(enclave->object,
- SGX_VA_PAGES_OFFS - SGX_SECS_VM_OBJECT_INDEX,
VM_ALLOC_NOCREAT);
sgx_page_remove(sc, p);
VM_OBJECT_WUNLOCK(object);
goto error;
}
mtx_lock(&sc->mtx_encls);
ret = sgx_ecreate(&pginfo, (void *)epc->base);
mtx_unlock(&sc->mtx_encls);
if (ret == SGX_EFAULT) {
dprintf("%s: gp fault\n", __func__);
mtx_unlock(&sc->mtx);
/* Remove VA page that was just created for SECS page. */
p = vm_page_grab(enclave->object,
- SGX_VA_PAGES_OFFS - SGX_SECS_VM_OBJECT_INDEX,
VM_ALLOC_NOCREAT);
sgx_page_remove(sc, p);
VM_OBJECT_WUNLOCK(object);
goto error;
}
TAILQ_INSERT_TAIL(&sc->enclaves, enclave, next);
mtx_unlock(&sc->mtx);
vmh->enclave = enclave;
page = PHYS_TO_VM_PAGE(epc->phys);
sgx_insert_epc_page_by_index(page, enclave->object,
SGX_SECS_VM_OBJECT_INDEX);
VM_OBJECT_WUNLOCK(object);
/* Release the reference. */
vm_object_deallocate(object);
free(secs, M_SGX);
return (0);
error:
free(secs, M_SGX);
sgx_put_epc_page(sc, epc);
free(enclave, M_SGX);
vm_object_deallocate(object);
return (ret);
}
static int
sgx_ioctl_add_page(struct sgx_softc *sc,
struct sgx_enclave_add_page *addp)
{
struct epc_page *secs_epc_page;
struct sgx_enclave *enclave;
struct sgx_vm_handle *vmh;
struct epc_page *epc;
struct page_info pginfo;
struct secinfo secinfo;
vm_object_t object;
void *tmp_vaddr;
uint64_t page_type;
struct tcs *t;
uint64_t addr;
uint64_t pidx;
vm_page_t p;
int ret;
tmp_vaddr = NULL;
epc = NULL;
object = NULL;
/* Find and get reference to VM object. */
ret = sgx_enclave_find(sc, addp->addr, &enclave);
if (ret) {
dprintf("%s: Failed to find enclave.\n", __func__);
goto error;
}
object = enclave->object;
KASSERT(object != NULL, ("vm object is NULL\n"));
vmh = object->handle;
ret = sgx_get_epc_page(sc, &epc);
if (ret) {
dprintf("%s: Failed to get free epc page.\n", __func__);
goto error;
}
memset(&secinfo, 0, sizeof(struct secinfo));
ret = copyin((void *)addp->secinfo, &secinfo,
sizeof(struct secinfo));
if (ret) {
dprintf("%s: Failed to copy secinfo.\n", __func__);
goto error;
}
tmp_vaddr = malloc(PAGE_SIZE, M_SGX, M_WAITOK | M_ZERO);
ret = copyin((void *)addp->src, tmp_vaddr, PAGE_SIZE);
if (ret) {
dprintf("%s: Failed to copy page.\n", __func__);
goto error;
}
page_type = (secinfo.flags & SECINFO_FLAGS_PT_M) >>
SECINFO_FLAGS_PT_S;
if (page_type != SGX_PT_TCS && page_type != SGX_PT_REG) {
dprintf("%s: page can't be added.\n", __func__);
goto error;
}
if (page_type == SGX_PT_TCS) {
t = (struct tcs *)tmp_vaddr;
ret = sgx_tcs_validate(t);
if (ret) {
dprintf("%s: TCS page validation failed.\n",
__func__);
goto error;
}
sgx_tcs_dump(sc, t);
}
addr = (addp->addr - vmh->base);
pidx = OFF_TO_IDX(addr);
VM_OBJECT_WLOCK(object);
p = vm_page_lookup(object, pidx);
if (p) {
VM_OBJECT_WUNLOCK(object);
/* Page already added. */
ret = ENXIO;
goto error;
}
ret = sgx_va_slot_init(sc, enclave, addr);
if (ret) {
VM_OBJECT_WUNLOCK(object);
dprintf("%s: Can't init va slot.\n", __func__);
goto error;
}
secs_epc_page = enclave->secs_epc_page;
memset(&pginfo, 0, sizeof(struct page_info));
pginfo.linaddr = (uint64_t)addp->addr;
pginfo.srcpge = (uint64_t)tmp_vaddr;
pginfo.secinfo = &secinfo;
pginfo.secs = (uint64_t)secs_epc_page->base;
mtx_lock(&sc->mtx_encls);
ret = sgx_eadd(&pginfo, (void *)epc->base);
if (ret == SGX_EFAULT) {
dprintf("%s: gp fault on eadd\n", __func__);
mtx_unlock(&sc->mtx_encls);
VM_OBJECT_WUNLOCK(object);
goto error;
}
mtx_unlock(&sc->mtx_encls);
ret = sgx_measure_page(sc, enclave->secs_epc_page, epc, addp->mrmask);
if (ret == SGX_EFAULT) {
dprintf("%s: gp fault on eextend\n", __func__);
sgx_epc_page_remove(sc, epc);
VM_OBJECT_WUNLOCK(object);
goto error;
}
sgx_insert_epc_page(enclave, epc, addr);
VM_OBJECT_WUNLOCK(object);
/* Release the reference. */
vm_object_deallocate(object);
free(tmp_vaddr, M_SGX);
return (0);
error:
free(tmp_vaddr, M_SGX);
sgx_put_epc_page(sc, epc);
vm_object_deallocate(object);
return (ret);
}
static int
sgx_ioctl_init(struct sgx_softc *sc, struct sgx_enclave_init *initp)
{
struct epc_page *secs_epc_page;
struct sgx_enclave *enclave;
struct thread *td;
void *tmp_vaddr;
void *einittoken;
void *sigstruct;
vm_object_t object;
int retry;
int ret;
td = curthread;
tmp_vaddr = NULL;
object = NULL;
dprintf("%s: addr %lx, sigstruct %lx, einittoken %lx\n",
__func__, initp->addr, initp->sigstruct, initp->einittoken);
/* Find and get reference to VM object. */
ret = sgx_enclave_find(sc, initp->addr, &enclave);
if (ret) {
dprintf("%s: Failed to find enclave.\n", __func__);
goto error;
}
object = enclave->object;
tmp_vaddr = malloc(PAGE_SIZE, M_SGX, M_WAITOK | M_ZERO);
sigstruct = tmp_vaddr;
einittoken = (void *)((uint64_t)sigstruct + PAGE_SIZE / 2);
ret = copyin((void *)initp->sigstruct, sigstruct,
SGX_SIGSTRUCT_SIZE);
if (ret) {
dprintf("%s: Failed to copy SIGSTRUCT page.\n", __func__);
goto error;
}
ret = copyin((void *)initp->einittoken, einittoken,
SGX_EINITTOKEN_SIZE);
if (ret) {
dprintf("%s: Failed to copy EINITTOKEN page.\n", __func__);
goto error;
}
secs_epc_page = enclave->secs_epc_page;
retry = 16;
do {
mtx_lock(&sc->mtx_encls);
ret = sgx_einit(sigstruct, (void *)secs_epc_page->base,
einittoken);
mtx_unlock(&sc->mtx_encls);
dprintf("%s: sgx_einit returned %d\n", __func__, ret);
} while (ret == SGX_UNMASKED_EVENT && retry--);
if (ret) {
dprintf("%s: Failed init enclave: %d\n", __func__, ret);
td->td_retval[0] = ret;
ret = 0;
}
error:
free(tmp_vaddr, M_SGX);
/* Release the reference. */
vm_object_deallocate(object);
return (ret);
}
static int
sgx_ioctl(struct cdev *dev, u_long cmd, caddr_t addr, int flags,
struct thread *td)
{
struct sgx_enclave_add_page *addp;
struct sgx_enclave_create *param;
struct sgx_enclave_init *initp;
struct sgx_softc *sc;
int ret;
int len;
sc = &sgx_sc;
len = IOCPARM_LEN(cmd);
dprintf("%s: cmd %lx, addr %lx, len %d\n",
__func__, cmd, (uint64_t)addr, len);
if (len > SGX_IOCTL_MAX_DATA_LEN)
return (EINVAL);
switch (cmd) {
case SGX_IOC_ENCLAVE_CREATE:
param = (struct sgx_enclave_create *)addr;
ret = sgx_ioctl_create(sc, param);
break;
case SGX_IOC_ENCLAVE_ADD_PAGE:
addp = (struct sgx_enclave_add_page *)addr;
ret = sgx_ioctl_add_page(sc, addp);
break;
case SGX_IOC_ENCLAVE_INIT:
initp = (struct sgx_enclave_init *)addr;
ret = sgx_ioctl_init(sc, initp);
break;
default:
return (EINVAL);
}
return (ret);
}
static int
sgx_mmap_single(struct cdev *cdev, vm_ooffset_t *offset,
vm_size_t mapsize, struct vm_object **objp, int nprot)
{
struct sgx_vm_handle *vmh;
struct sgx_softc *sc;
sc = &sgx_sc;
dprintf("%s: mapsize 0x%lx, offset %lx\n",
__func__, mapsize, *offset);
vmh = malloc(sizeof(struct sgx_vm_handle),
M_SGX, M_WAITOK | M_ZERO);
vmh->sc = sc;
vmh->size = mapsize;
vmh->mem = cdev_pager_allocate(vmh, OBJT_MGTDEVICE, &sgx_pg_ops,
mapsize, nprot, *offset, NULL);
if (vmh->mem == NULL) {
free(vmh, M_SGX);
return (ENOMEM);
}
VM_OBJECT_WLOCK(vmh->mem);
vm_object_set_flag(vmh->mem, OBJ_PG_DTOR);
VM_OBJECT_WUNLOCK(vmh->mem);
*objp = vmh->mem;
return (0);
}
static struct cdevsw sgx_cdevsw = {
.d_version = D_VERSION,
.d_ioctl = sgx_ioctl,
.d_mmap_single = sgx_mmap_single,
.d_name = "Intel SGX",
};
static int
sgx_get_epc_area(struct sgx_softc *sc)
{
vm_offset_t epc_base_vaddr;
u_int cp[4];
int error;
int i;
cpuid_count(SGX_CPUID, 0x2, cp);
sc->epc_base = ((uint64_t)(cp[1] & 0xfffff) << 32) +
(cp[0] & 0xfffff000);
sc->epc_size = ((uint64_t)(cp[3] & 0xfffff) << 32) +
(cp[2] & 0xfffff000);
sc->npages = sc->epc_size / SGX_PAGE_SIZE;
if (sc->epc_size == 0 || sc->epc_base == 0) {
printf("%s: Incorrect EPC data: EPC base %lx, size %lu\n",
__func__, sc->epc_base, sc->epc_size);
return (EINVAL);
}
if (cp[3] & 0xffff)
sc->enclave_size_max = (1 << ((cp[3] >> 8) & 0xff));
else
sc->enclave_size_max = SGX_ENCL_SIZE_MAX_DEF;
epc_base_vaddr = (vm_offset_t)pmap_mapdev_attr(sc->epc_base,
sc->epc_size, VM_MEMATTR_DEFAULT);
sc->epc_pages = malloc(sizeof(struct epc_page) * sc->npages,
M_DEVBUF, M_WAITOK | M_ZERO);
for (i = 0; i < sc->npages; i++) {
sc->epc_pages[i].base = epc_base_vaddr + SGX_PAGE_SIZE * i;
sc->epc_pages[i].phys = sc->epc_base + SGX_PAGE_SIZE * i;
sc->epc_pages[i].index = i;
}
sc->vmem_epc = vmem_create("SGX EPC", sc->epc_base, sc->epc_size,
PAGE_SIZE, PAGE_SIZE, M_FIRSTFIT | M_WAITOK);
if (sc->vmem_epc == NULL) {
printf("%s: Can't create vmem arena.\n", __func__);
free(sc->epc_pages, M_SGX);
return (EINVAL);
}
error = vm_phys_fictitious_reg_range(sc->epc_base,
sc->epc_base + sc->epc_size, VM_MEMATTR_DEFAULT);
if (error) {
printf("%s: Can't register fictitious space.\n", __func__);
free(sc->epc_pages, M_SGX);
return (EINVAL);
}
return (0);
}
static void
sgx_put_epc_area(struct sgx_softc *sc)
{
vm_phys_fictitious_unreg_range(sc->epc_base,
sc->epc_base + sc->epc_size);
free(sc->epc_pages, M_SGX);
}
static int
sgx_load(void)
{
struct sgx_softc *sc;
int error;
sc = &sgx_sc;
if ((cpu_stdext_feature & CPUID_STDEXT_SGX) == 0)
return (ENXIO);
error = sgx_get_epc_area(sc);
if (error) {
printf("%s: Failed to get Processor Reserved Memory area.\n",
__func__);
return (ENXIO);
}
mtx_init(&sc->mtx_encls, "SGX ENCLS", NULL, MTX_DEF);
mtx_init(&sc->mtx, "SGX driver", NULL, MTX_DEF);
TAILQ_INIT(&sc->enclaves);
sc->sgx_cdev = make_dev(&sgx_cdevsw, 0, UID_ROOT, GID_WHEEL,
0600, "isgx");
sc->state |= SGX_STATE_RUNNING;
printf("SGX initialized: EPC base 0x%lx size %ld (%d pages)\n",
sc->epc_base, sc->epc_size, sc->npages);
return (0);
}
static int
sgx_unload(void)
{
struct sgx_softc *sc;
sc = &sgx_sc;
if ((sc->state & SGX_STATE_RUNNING) == 0)
return (0);
mtx_lock(&sc->mtx);
if (!TAILQ_EMPTY(&sc->enclaves)) {
mtx_unlock(&sc->mtx);
return (EBUSY);
}
sc->state &= ~SGX_STATE_RUNNING;
mtx_unlock(&sc->mtx);
destroy_dev(sc->sgx_cdev);
vmem_destroy(sc->vmem_epc);
sgx_put_epc_area(sc);
mtx_destroy(&sc->mtx_encls);
mtx_destroy(&sc->mtx);
return (0);
}
static int
sgx_handler(module_t mod, int what, void *arg)
{
int error;
switch (what) {
case MOD_LOAD:
error = sgx_load();
break;
case MOD_UNLOAD:
error = sgx_unload();
break;
default:
error = 0;
break;
}
return (error);
}
static moduledata_t sgx_kmod = {
"sgx",
sgx_handler,
NULL
};
DECLARE_MODULE(sgx, sgx_kmod, SI_SUB_LAST, SI_ORDER_ANY);
MODULE_VERSION(sgx, 1);