diff options
Diffstat (limited to 'hw/misc/max78000_aes.c')
| -rw-r--r-- | hw/misc/max78000_aes.c | 223 |
1 files changed, 223 insertions, 0 deletions
diff --git a/hw/misc/max78000_aes.c b/hw/misc/max78000_aes.c new file mode 100644 index 0000000..0bfb2f0 --- /dev/null +++ b/hw/misc/max78000_aes.c @@ -0,0 +1,223 @@ +/* + * MAX78000 AES + * + * Copyright (c) 2025 Jackson Donaldson <jcksn@duck.com> + * + * SPDX-License-Identifier: GPL-2.0-or-later + */ + +#include "qemu/osdep.h" +#include "qemu/log.h" +#include "trace.h" +#include "hw/irq.h" +#include "migration/vmstate.h" +#include "hw/misc/max78000_aes.h" +#include "crypto/aes.h" + +static void max78000_aes_set_status(Max78000AesState *s) +{ + s->status = 0; + if (s->result_index >= 16) { + s->status |= OUTPUT_FULL; + } + if (s->result_index == 0) { + s->status |= OUTPUT_EMPTY; + } + if (s->data_index >= 16) { + s->status |= INPUT_FULL; + } + if (s->data_index == 0) { + s->status |= INPUT_EMPTY; + } +} + +static uint64_t max78000_aes_read(void *opaque, hwaddr addr, + unsigned int size) +{ + Max78000AesState *s = opaque; + switch (addr) { + case CTRL: + return s->ctrl; + + case STATUS: + return s->status; + + case INTFL: + return s->intfl; + + case INTEN: + return s->inten; + + case FIFO: + if (s->result_index >= 4) { + s->intfl &= ~DONE; + s->result_index -= 4; + max78000_aes_set_status(s); + return ldl_be_p(&s->result[s->result_index]); + } else{ + return 0; + } + + default: + qemu_log_mask(LOG_GUEST_ERROR, "%s: Bad offset 0x%" + HWADDR_PRIx "\n", __func__, addr); + break; + + } + return 0; +} + +static void max78000_aes_do_crypto(Max78000AesState *s) +{ + int keylen = 256; + uint8_t *keydata = s->key; + if ((s->ctrl & KEY_SIZE) == 0) { + keylen = 128; + keydata += 16; + } else if ((s->ctrl & KEY_SIZE) == 1 << 6) { + keylen = 192; + keydata += 8; + } + + AES_KEY key; + if ((s->ctrl & TYPE) == 0) { + AES_set_encrypt_key(keydata, keylen, &key); + AES_set_decrypt_key(keydata, keylen, &s->internal_key); + AES_encrypt(s->data, s->result, &key); + s->result_index = 16; + } else if ((s->ctrl & TYPE) == 1 << 8) { + AES_set_decrypt_key(keydata, keylen, &key); + AES_set_decrypt_key(keydata, keylen, &s->internal_key); + AES_decrypt(s->data, s->result, &key); + s->result_index = 16; + } else{ + AES_decrypt(s->data, s->result, &s->internal_key); + s->result_index = 16; + } + s->intfl |= DONE; +} + +static void max78000_aes_write(void *opaque, hwaddr addr, + uint64_t val64, unsigned int size) +{ + Max78000AesState *s = opaque; + uint32_t val = val64; + switch (addr) { + case CTRL: + if (val & OUTPUT_FLUSH) { + s->result_index = 0; + val &= ~OUTPUT_FLUSH; + } + if (val & INPUT_FLUSH) { + s->data_index = 0; + val &= ~INPUT_FLUSH; + } + if (val & START) { + max78000_aes_do_crypto(s); + } + + /* Hardware appears to stay enabled even if 0 written */ + s->ctrl = val | (s->ctrl & AES_EN); + break; + + case FIFO: + assert(s->data_index <= 12); + stl_be_p(&s->data[12 - s->data_index], val); + s->data_index += 4; + if (s->data_index >= 16) { + s->data_index = 0; + max78000_aes_do_crypto(s); + } + break; + + case KEY_BASE ... KEY_END - 4: + stl_be_p(&s->key[(KEY_END - KEY_BASE - 4) - (addr - KEY_BASE)], val); + break; + + default: + qemu_log_mask(LOG_GUEST_ERROR, "%s: Bad offset 0x%" + HWADDR_PRIx "\n", __func__, addr); + break; + + } + max78000_aes_set_status(s); +} + +static void max78000_aes_reset_hold(Object *obj, ResetType type) +{ + Max78000AesState *s = MAX78000_AES(obj); + s->ctrl = 0; + s->status = 0; + s->intfl = 0; + s->inten = 0; + + s->data_index = 0; + s->result_index = 0; + + memset(s->data, 0, sizeof(s->data)); + memset(s->key, 0, sizeof(s->key)); + memset(s->result, 0, sizeof(s->result)); + memset(&s->internal_key, 0, sizeof(s->internal_key)); +} + +static const MemoryRegionOps max78000_aes_ops = { + .read = max78000_aes_read, + .write = max78000_aes_write, + .endianness = DEVICE_LITTLE_ENDIAN, + .valid.min_access_size = 4, + .valid.max_access_size = 4, +}; + +static const VMStateDescription vmstate_max78000_aes = { + .name = TYPE_MAX78000_AES, + .version_id = 1, + .minimum_version_id = 1, + .fields = (const VMStateField[]) { + VMSTATE_UINT32(ctrl, Max78000AesState), + VMSTATE_UINT32(status, Max78000AesState), + VMSTATE_UINT32(intfl, Max78000AesState), + VMSTATE_UINT32(inten, Max78000AesState), + VMSTATE_UINT8_ARRAY(data, Max78000AesState, 16), + VMSTATE_UINT8_ARRAY(key, Max78000AesState, 32), + VMSTATE_UINT8_ARRAY(result, Max78000AesState, 16), + VMSTATE_UINT32_ARRAY(internal_key.rd_key, Max78000AesState, 60), + VMSTATE_INT32(internal_key.rounds, Max78000AesState), + VMSTATE_END_OF_LIST() + } +}; + +static void max78000_aes_init(Object *obj) +{ + Max78000AesState *s = MAX78000_AES(obj); + sysbus_init_irq(SYS_BUS_DEVICE(obj), &s->irq); + + memory_region_init_io(&s->mmio, obj, &max78000_aes_ops, s, + TYPE_MAX78000_AES, 0xc00); + sysbus_init_mmio(SYS_BUS_DEVICE(obj), &s->mmio); + +} + +static void max78000_aes_class_init(ObjectClass *klass, const void *data) +{ + ResettableClass *rc = RESETTABLE_CLASS(klass); + DeviceClass *dc = DEVICE_CLASS(klass); + + rc->phases.hold = max78000_aes_reset_hold; + dc->vmsd = &vmstate_max78000_aes; + +} + +static const TypeInfo max78000_aes_info = { + .name = TYPE_MAX78000_AES, + .parent = TYPE_SYS_BUS_DEVICE, + .instance_size = sizeof(Max78000AesState), + .instance_init = max78000_aes_init, + .class_init = max78000_aes_class_init, +}; + +static void max78000_aes_register_types(void) +{ + type_register_static(&max78000_aes_info); +} + +type_init(max78000_aes_register_types) |