TSEC Firmware
Boot Process
TSEC is configured and initialized by the first bootloader during key generation.
[6.2.0+] TSEC is now configured at the end of the first bootloader's main function.
Initialization
During this stage several clocks are programmed.
// Program the HOST1X clock and resets
// Uses RST_DEVICES_L, CLK_OUT_ENB_L, CLK_SOURCE_HOST1X and CLK_L_HOST1X
enable_host1x_clkrst();
// Program the TSEC clock and resets
// Uses RST_DEVICES_U, CLK_OUT_ENB_U, CLK_SOURCE_TSEC and CLK_U_TSEC
enable_tsec_clkrst();
// Program the SOR_SAFE clock and resets
// Uses RST_DEVICES_Y, CLK_OUT_ENB_Y and CLK_Y_SOR_SAFE
enable_sor_safe_clkrst();
// Program the SOR0 clock and resets
// Uses RST_DEVICES_X, CLK_OUT_ENB_X and CLK_X_SOR0
enable_sor0_clkrst();
// Program the SOR1 clock and resets
// Uses RST_DEVICES_X, CLK_OUT_ENB_X, CLK_SOURCE_SOR1 and CLK_X_SOR1
enable_sor1_clkrst();
// Program the KFUSE clock resets
// Uses RST_DEVICES_H, CLK_OUT_ENB_H and CLK_H_KFUSE
enable_kfuse_clkrst();
Configuration
In this stage the Falcon IRQs, interfaces and DMA engine are configured.
// Clear the Falcon DMA control register
*(u32 *)FALCON_DMACTL = 0;
// Enable Falcon IRQs
*(u32 *)FALCON_IRQMSET = 0xFFF2;
// Enable Falcon IRQs
*(u32 *)FALCON_IRQDEST = 0xFFF0;
// Enable Falcon interfaces
*(u32 *)FALCON_ITFEN = 0x03;
// Wait for Falcon's DMA engine to be idle
wait_flcn_dma_idle();
Firmware loading
The Falcon firmware code is stored in the first bootloader's data segment in IMEM.
// Set DMA transfer base address to 0x40011900 >> 0x08
*(u32 *)FALCON_DMATRFBASE = 0x400119;
u32 trf_mode = 0; // A value of 0 sets FALCON_DMATRFCMD_IMEM
u32 dst_offset = 0;
u32 src_offset = 0;
// Load code into Falcon (0x100 bytes at a time)
while (src_offset < 0xF00)
{
flcn_load_firm(trf_mode, src_offset, dst_offset);
src_offset += 0x100;
dst_offset += 0x100;
}
[6.2.0+] The transfer base address and size of the Falcon firmware code changed.
// Set DMA transfer base address to 0x40010E00 >> 0x08
*(u32 *)FALCON_DMATRFBASE = 0x40010E;
u32 trf_mode = 0; // A value of 0 sets FALCON_DMATRFCMD_IMEM
u32 dst_offset = 0;
u32 src_offset = 0;
// Load code into Falcon (0x100 bytes at a time)
while (src_offset < 0x2900)
{
flcn_load_firm(trf_mode, src_offset, dst_offset);
src_offset += 0x100;
dst_offset += 0x100;
}
Firmware booting
Falcon is booted up and the first bootloader waits for it to finish.
// Set magic value in host1x scratch space
*(u32 *)0x50003300 = 0x34C2E1DA;
// Clear Falcon scratch1 MMIO
*(u32 *)FALCON_SCRATCH1 = 0;
// Set Falcon boot key version in scratch0 MMIO
*(u32 *)FALCON_SCRATCH0 = 0x01;
// Set Falcon's boot vector address
*(u32 *)FALCON_BOOTVEC = 0;
// Signal Falcon's CPU
*(u32 *)FALCON_CPUCTL = 0x02;
// Wait for Falcon's DMA engine to be idle
wait_flcn_dma_idle();
u32 boot_res = 0;
// The bootloader allows the TSEC two seconds from this point to do its job
u32 maximum_time = read_timer() + 2000000;
while (!boot_res)
{
// Read boot result from scratch1 MMIO
boot_res = *(u32 *)FALCON_SCRATCH1;
// Read from TIMERUS_CNTR_1US (microseconds from boot)
u32 current_time = read_timer();
// Booting is taking too long
if (current_time > maximum_time)
panic();
}
// Invalid boot result was returned
if (boot_resĀ != 0xB0B0B0B0)
panic();
[6.2.0+] Falcon is booted up, but the first bootloader is left in an infinite loop.
// Set magic value in host1x scratch space
*(u32 *)0x50003300 = 0x34C2E1DA;
// Clear Falcon scratch1 MMIO
*(u32 *)FALCON_SCRATCH1 = 0;
// Set Falcon boot key version in scratch0 MMIO
*(u32 *)FALCON_SCRATCH0 = 0x01;
// Set Falcon's boot vector address
*(u32 *)FALCON_BOOTVEC = 0;
// Signal Falcon's CPU
*(u32 *)FALCON_CPUCTL = 0x02;
// Infinite loop
while (1);
TSEC key generation
The TSEC key is generated by reading SOR1 registers modified by the Falcon CPU.
// Clear magic value in host1x scratch space
*(u32 *)0x50003300 = 0;
// Read TSEC key
u32 tsec_key[4];
tsec_key[0] = *(u32 *)NV_SOR_DP_HDCP_BKSV_LSB;
tsec_key[1] = *(u32 *)NV_SOR_TMDS_HDCP_BKSV_LSB;
tsec_key[2] = *(u32 *)NV_SOR_TMDS_HDCP_CN_MSB;
tsec_key[3] = *(u32 *)NV_SOR_TMDS_HDCP_CN_LSB;
// Clear SOR1 registers
*(u32 *)NV_SOR_DP_HDCP_BKSV_LSB = 0;
*(u32 *)NV_SOR_TMDS_HDCP_BKSV_LSB = 0;
*(u32 *)NV_SOR_TMDS_HDCP_CN_MSB = 0;
*(u32 *)NV_SOR_TMDS_HDCP_CN_LSB = 0;
if (out_size < 0x10)
out_size = 0x10;
// Copy back the TSEC key
memcpy(out_buf, tsec_key, out_size);
[6.2.0+] This is now done inside an encrypted TSEC payload.
Cleanup
Clocks and resets are disabled before returning.
// Deprogram KFUSE clock and resets
// Uses RST_DEVICES_H, CLK_OUT_ENB_H and CLK_H_KFUSE
disable_kfuse_clkrst();
// Deprogram SOR1 clock and resets
// Uses RST_DEVICES_X, CLK_OUT_ENB_X, CLK_SOURCE_SOR1 and CLK_X_SOR1
disable_sor1_clkrst();
// Deprogram SOR0 clock and resets
// Uses RST_DEVICES_X, CLK_OUT_ENB_X and CLK_X_SOR0
disable_sor0_clkrst();
// Deprogram SOR_SAFE clock and resets
// Uses RST_DEVICES_Y, CLK_OUT_ENB_Y and CLK_Y_SOR_SAFE
disable_sor_safe_clkrst();
// Deprogram TSEC clock and resets
// Uses RST_DEVICES_U, CLK_OUT_ENB_U, CLK_SOURCE_TSEC and CLK_U_TSEC
disable_tsec_clkrst();
// Deprogram HOST1X clock and resets
// Uses RST_DEVICES_L, CLK_OUT_ENB_L, CLK_SOURCE_HOST1X and CLK_L_HOST1X
disable_host1x_clkrst();
TSEC Firmware
The actual code loaded into TSEC is assembled in NVIDIA's proprietary fuc5 ISA using crypto extensions. Stored inside the first bootloader, this firmware binary is split into 4 blobs (names are unofficial): Boot (unencrypted and unauthenticated code), KeygenLdr (unencrypted and authenticated code), Keygen (encrypted and authenticated code) and key data.
[6.2.0+] There are now 2 new blobs (names are unofficial): SecureBootLdr (unencrypted and unauthenticated code), SecureBoot (part unencrypted and unauthenticated code, part encrypted and authenticated code).
Firmware can be disassembled with envytools' envydis:
envydis -i tsec_fw.bin -m falcon -V fuc5 -F crypt
Note that the instruction set has variable length instructions, and the disassembler is not very good at detecting locations it should start disassembling from. One needs to disassemble multiple sub-regions and join them together.
Boot
During this stage, key data is loaded and KeygenLdr is authenticated, loaded and executed. Before returning, this stage writes back to the host (using MMIO registers) and sets the key used by the first bootloader.
[6.2.0+] During this stage, key data is loaded and execution jumps to SecureBootLdr.
Initialization
The firmware initially sets up the stack pointer to the end of the available data segment.
// Read data segment size from IO space
u32 data_seg_size = *(u32 *)FALCON_HWCFG;
data_seg_size >>= 0x09;
data_seg_size &= 0x1FF;
data_seg_size <<= 0x08;
// Set the stack pointer
*(u32 *)sp = data_seg_size;
Main
The firmware reads the key data blob and then loads, authenticates and executes KeygenLdr which sets the TSEC key.
u32 dmem_start = 0;
u8 key_data_buf[0x7C];
// Read the key data blob from code segment
u32 key_data_addr = 0x300;
u32 key_data_size = 0x7C;
memcpy_i2d(key_data_buf, key_data_addr, key_data_size);
// Read the next stage from code segment into data space
u32 blob1_addr = 0x400;
u32 blob1_size = *(u32 *)(key_data_buf + 0x74);
memcpy_i2d(dmem_start, blob1_addr, blob1_size);
// Upload the next stage into Falcon's code segment
u32 blob1_virt_addr = 0x300;
bool use_secret = true;
memcpy_d2i(blob1_virt_addr, dmem_start, blob1_size, blob1_virt_addr, use_secret);
u32 boot_res = 0;
u32 time = 0;
bool is_blob_dec = false;
while (true)
{
if (time == 4000001)
{
// Write boot failed (timeout) magic to FALCON_SCRATCH1
boot_res = 0xC0C0C0C0;
*(u32 *)FALCON_SCRATCH1 = boot_res;
break;
}
// Load key version from FALCON_SCRATCH0 (bootloader sends 0x01)
u32 key_version = *(u32 *)FALCON_SCRATCH0;
if (key_version == 0x64)
{
// Skip all next stages
boot_res = 0xB0B0B0B0;
*(u32 *)FALCON_SCRATCH1 = boot_res;
break;
}
else
{
if (key_version > 0x03)
boot_res = 0xD0D0D0D0; // Invalid key version
else if (key_version == 0)
boot_res = 0xB0B0B0B0; // No keys used
else
{
u32 key_buf[0x7C];
// Copy key data
memcpy(key_buf, key_data_buf, 0x7C);
u32 crypto_reg_flag = 0x00060000;
u32 blob1_hash_addr = key_buf + 0x20;
// Set auth_addr to 0x300 and auth_size to blob1_size
$cauth = ((blob1_size << 0x10) | 0x03);
// The next 2 xfer instructions will be overridden
// and target changes from DMA to crypto
cxset(0x02);
// Transfer data to crypto register c6
xdst(0, (blob1_hash_addr | crypto_reg_flag));
// Wait for all data loads/stores to finish
xdwait();
// Jump to KeygenLdr
u32 keygenldr_res = exec_keygenldr(key_buf, key_version, is_blob_dec);
is_blob_dec = true; // Set this to prevent decrypting again
// Set boot finish magic on success
if (keygenldr_res == 0)
boot_res = 0xB0B0B0B0
}
// Write result to FALCON_SCRATCH1
*(u32 *)FALCON_SCRATCH1 = boot_res;
if (boot_res == 0xB0B0B0B0)
break;
}
time++;
}
// Overwrite the TSEC key in SOR1 registers
// This has no effect because the KeygenLdr locks out the TSEC DMA engine
tsec_set_key(key_data_buf);
return boot_res;
[6.2.0+] The firmware calculates the start address of SecureBootLdr through key data and jumps to it.
u8 key_data_buf[0x84];
// Read the key data blob
u32 key_data_addr = 0x300;
u32 key_data_size = 0x84;
memcpy_i2d(key_data_buf, key_data_addr, key_data_size);
// Calculate the next blob's address in Falcon code segment
u32 blob4_size = *(u32 *)(key_data_buf + 0x80);
u32 blob0_size = *(u32 *)(key_data_buf + 0x70);
u32 blob1_size = *(u32 *)(key_data_buf + 0x74);
u32 blob2_size = *(u32 *)(key_data_buf + 0x78);
u32 blob3_addr = blob0_size + blob1_size + 0x100 + blob2_size + blob4_size;
// Jump to next blob
(void *)blob3_addr();
return 0;
tsec_set_key
This method takes key_data_buf (a 16 bytes buffer) as argument and writes its contents to SOR1 registers.
// This is TSEC_MMIO + 0x1000 + (0x1C300 / 0x40)
*(u32 *)TSEC_DMA_TIMEOUT = 0xFFF;
// Read the key's words
u32 key0 = *(u32 *)(key_data_buf + 0x00);
u32 key1 = *(u32 *)(key_data_buf + 0x04);
u32 key2 = *(u32 *)(key_data_buf + 0x08);
u32 key3 = *(u32 *)(key_data_buf + 0x0C);
u32 result = 0;
// Write key0 to SOR1 and check for errors
result = tsec_dma_write(NV_SOR_DP_HDCP_BKSV_LSB, key0);
if (result)
return result;
// Write key1 to SOR1 and check for errors
result = tsec_dma_write(NV_SOR_TMDS_HDCP_BKSV_LSB, key1);
if (result)
return result;
// Write key2 to SOR1 and check for errors
result = tsec_dma_write(NV_SOR_TMDS_HDCP_CN_MSB, key2);
if (result)
return result;
// Write key3 to SOR1 and check for errors
result = tsec_dma_write(NV_SOR_TMDS_HDCP_CN_LSB, key3);
if (result)
return result;
return result;
tsec_dma_write
This method takes addr and value as arguments and performs a DMA write using TSEC MMIO.
u32 result = 0;
// Wait for TSEC DMA engine
// This waits for bit 0x0C in TSEC_DMA_CMD to be 0
result = wait_tsec_dma();
// Wait failed
if (result)
return 1;
// Set the destination address
// This is TSEC_MMIO + 0x1000 + (0x1C100 / 0x40)
*(u32 *)TSEC_DMA_ADDR = addr;
// Set the value
// This is TSEC_MMIO + 0x1000 + (0x1C200 / 0x40)
*(u32 *)TSEC_DMA_VAL = value;
// Start transfer
// This is TSEC_MMIO + 0x1000 + (0x1C000 / 0x40)
*(u32 *)TSEC_DMA_CMD = 0x800000F2;
// Wait for TSEC DMA engine
// This waits for bit 0x0C in TSEC_DMA_CMD to be 0
result = wait_tsec_dma();
// Wait failed
if (result)
return 1;
return 0;
KeygenLdr
This stage is responsible for reconfiguring the Falcon's crypto co-processor and loading, decrypting, authenticating and executing Keygen.
Main
// Clear interrupt flags
$flags.ie0 = 0;
$flags.ie1 = 0;
$flags.ie2 = 0;
// Clear overrides
cxset(0x80);
// Clear bit 0x13 in cauth
$cauth = ($cauth & ~(1 << 0x13));
// Set the target port for memory transfers
$xtargets = 0;
// Wait for all data loads/stores to finish
xdwait();
// Wait for all code loads to finish
xcwait();
// The next 2 xfer instructions will be overridden
// and target changes from DMA to crypto
cxset(0x02);
// Transfer data to crypto register c0
// This should clear any leftover data
xdst(0, 0);
// Wait for all data loads/stores to finish
xdwait();
// Clear all crypto registers, except c6 which is used for auth
cxor($c0, $c0);
cmov($c1, $c0);
cmov($c2, $c0);
cmov($c3, $c0);
cmov($c4, $c0);
cmov($c5, $c0);
cmov($c7, $c0);
// Clear TSEC_TEGRA_CTL_TKFI_KFUSE
// This is TSEC_MMIO + 0x1000 + (0x20E00 / 0x40)
*(u32 *)TSEC_TEGRA_CTL &= 0xFFFEFFFF;
// Set TSEC_SCP_CTL_PKEY_REQUEST_RELOAD
// This is TSEC_MMIO + 0x1000 + (0x10600 / 0x40)
*(u32 *)TSEC_SCP_CTL_PKEY |= 0x01;
u32 is_pkey_loaded = 0;
// Wait for TSEC_SCP_CTL_PKEY_LOADED
while (!is_pkey_loaded)
is_pkey_loaded = (*(u32 *)TSEC_SCP_CTL_PKEY & 0x02);
// Read data segment size from IO space
u32 data_seg_size = *(u32 *)FALCON_HWCFG;
data_seg_size >>= 0x09;
data_seg_size &= 0x1FF;
data_seg_size <<= 0x08;
// Check stack bounds
if (($sp >= data_seg_size) || ($sp < 0x800))
exit();
// Load and execute the Keygen stage
load_keygen(key_buf, key_version, is_blob_dec);
// Clear the cauth signature
csigclr();
// Clear all crypto registers
cxor($c0, $c0);
cxor($c1, $c1);
cxor($c2, $c2);
cxor($c3, $c3);
cxor($c4, $c4);
cxor($c5, $c5);
cxor($c6, $c6);
cxor($c7, $c7);
// Take SCP out of lockdown
// This is TSEC_MMIO + 0x1000 + (0x10300 / 0x40)
*(u32 *)TSEC_SCP_CTL_LOCK = 0;
return;
load_keygen
This method takes key_buf, key_version and is_blob_dec as arguments and is responsible for loading, decrypting, authenticating and executing Keygen. Notably, it also does AES-CMAC over the unauthorized Boot blob to make sure it hasn't been tampered with.
u32 res = 0;
u32 dmem_start = 0;
u32 blob0_addr = 0;
u32 blob0_size = *(u32 *)(key_buf + 0x70);
// Load blob0 code to the start of the data segment
memcpy_i2d(dmem_start, blob0_addr, blob0_size);
// Generate "CODE_SIG_01" key into c4 crypto register
gen_usr_key(0, 0);
// Encrypt buffer with c4
u8 sig_key[0x10];
enc_buf(sig_key, blob0_size);
u32 src_addr = dmem_start;
u32 src_size = blob0_size;
u32 iv_addr = sig_key;
u32 dst_addr = sig_key;
u32 mode = 0x02; // AES-CMAC
u32 use_imem = 0;
// Do AES-CMAC over blob0 code
do_crypto(src_addr, src_size, iv_addr, dst_addr, mode, use_imem);
// Compare the resulting hash with the one from the key buffer
if (memcmp(dst_addr, key_buf + 0x10, 0x10))
{
res = 0xDEADBEEF;
return res;
}
u32 blob1_size = *(u32 *)(key_buf + 0x74);
// Decrypt Keygen blob if needed
if (!is_blob_dec)
{
// Read Stage2's size from key buffer
u32 blob2_size = *(u32 *)(key_buf + 0x78);
// Check stack bounds
if ($sp > blob2_size)
{
u32 blob2_virt_addr = blob0_size + blob1_size;
u32 blob2_phys_addr = blob2_virt_addr + 0x100;
// Read the encrypted Keygen blob
memcpy_i2d(dmem_start, blob2_phys_addr, blob2_size);
// Generate "CODE_ENC_01" key into c4 crypto register
gen_usr_key(0x01, 0x01);
u32 src_addr = dmem_start;
u32 src_size = blob2_size;
u32 iv_addr = key_buf + 0x40;
u32 dst_addr = dmem_start;
u32 mode = 0; // AES-128-CBC
u32 use_imem = 0;
// Decrypt Keygen blob with AES-128-CBC
do_crypto(src_addr, src_size, iv_addr, dst_addr, mode, use_imem);
// Upload decrypted Keygen into Falcon's code segment
bool use_secret = true;
memcpy_d2i(blob2_virt_addr, dmem_start, blob2_size, blob2_virt_addr, use_secret);
// Clear out the decrypted blob
memset(dmem_start, 0, blob2_size);
}
}
// The next 2 xfer instructions will be overridden
// and target changes from DMA to crypto
cxset(0x02);
u32 crypto_reg_flag = 0x00060000;
u32 blob2_hash_addr = key_buf + 0x30;
// Transfer the Keygen auth hash to crypto register c6
xdst(0, (blob2_hash_addr | crypto_reg_flag));
// Wait for all data loads/stores to finish
xdwait();
// Save previous cauth value
u32 cauth_old = $cauth;
// Set auth_addr to blob2_virt_addr and auth_size to blob2_size
$cauth = ((blob2_virt_addr >> 0x08) | (blob2_size << 0x10));
u32 hovi_key_addr = 0;
// Select next stage key
if (key_version == 0x01) // Use HOVI_EKS_01
hovi_key_addr = key_buf + 0x50;
else if (key_version == 0x02) // Use HOVI_COMMON_01
hovi_key_addr = key_buf + 0x60;
else if (key_version == 0x03) // Use debug key (empty)
hovi_key_addr = key_buf + 0x00;
else
res = 0xD0D0D0D0
// Jump to Keygen
if (hovi_key_addr)
res = exec_keygen(hovi_key_addr, key_version);
// Clear out key data
memset(key_buf, 0, 0x7C);
// Restore previous cauth value
$cauth = cauth_old;
return res;
gen_usr_key
This method takes type and mode as arguments and generates a key.
u8 seed_buf[0x10];
// Read a 16 bytes seed based on supplied type
/*
type == 0: "CODE_SIG_01" + null padding
type == 1: "CODE_ENC_01" + null padding
*/
get_seed(seed_buf, type);
// This will write the seed into crypto register c0
crypto_store(0, seed_buf);
// Load selected secret into crypto register c1
csecret($c1, 0x26);
// Bind c1 register as the key for enc/dec operations
ckeyreg($c1);
// Encrypt seed_buf in c0 using keyreg value as key into c1
cenc($c1, $c0);
// Encrypt the auth signature (stored in c6) with c1 and store in c1
csigenc($c1, $c1);
// Copy the result to c4 (will be used as key)
cmov($c4, $c1);
// Do key expansion for decryption if necessary
if (modeĀ != 0)
ckexp($c4, $c4);
return;
enc_buf
This method takes buf (a 16 bytes buffer) and size as arguments and encrypts the supplied buffer.
// Set first 3 words to null
*(u32 *)(buf + 0x00) = 0;
*(u32 *)(buf + 0x04) = 0;
*(u32 *)(buf + 0x08) = 0;
// Swap halves (b16, b32 and b16 again) and store it as the last word
*(u32 *)(buf + 0x0C) = (
((size & 0x000000FF) << 0x08
| (size & 0x0000FF00) >> 0x08) << 0x10
| ((size & 0x00FF0000) >> 0x10) << 0x08
| (size & 0xFF000000) >> 0x18
);
// This will write buf into crypto register c3
crypto_store(0x03, buf);
// Bind c4 register as the key for enc/dec operations
ckeyreg($c4);
// Encrypt buf in c3 using keyreg value as key and store in c5
cenc($c5, $c3);
// This will read into buf from crypto register c5
crypto_load(0x05, buf);
return;
crypto_store
This method takes reg (a crypto register) and buf (a 16 bytes buffer) as arguments and loads the supplied buffer into the crypto register.
// The next two xfer instructions will be overridden
// and target changes from DMA to crypto
cxset(0x02);
// Encode the source buffer and the destination register for the xfer
u32 crypto_xfer_flag = (u32)buf | reg << 0x10;
// Transfer the supplied buffer to the supplied crypto register
xdst(crypto_xfer_flag, crypto_xfer_flag);
// Wait for all data loads/stores to finish
xdwait();
return;
crypto_load
This method takes reg (a crypto register) and buf (a 16 bytes buffer) as arguments and loads the contents of the supplied register into the supplied buffer.
// The next two xfer instructions will be overridden
// and target changes from DMA to crypto
cxset(0x02);
// Encode the destination buffer and the source register for the xfer
u32 crypto_xfer_flag = (u32)buf | reg << 0x10;
// Transfer the contents of the supplied crypto register into the supplied buffer
xdld(crypto_xfer_flag, crypto_xfer_flag);
// Wait for all data loads/stores to finish
xdwait();
return;
do_crypto
This is the method responsible for all crypto operations performed during KeygenLdr. It takes src_addr, src_size, iv_addr, dst_addr, mode and use_imem as arguments.
// Check for invalid source data size
if (!src_size || (src_size & 0x0F))
exit();
// Check for invalid source data address
if (src_addr & 0x0F)
exit();
// Check for invalid destination data address
if (dst_addr & 0x0F)
exit();
// Use IV if available
if (iv_addr)
{
// This will write the iv_addr into crypto register c5
crypto_store(0x05, iv_addr);
}
else
{
// Clear c5 register (use null IV)
cxor($c5, $c5);
}
// Bind c4 register as the key for enc/dec operations
ckeyreg(c4);
if (mode == 0x00) // AES-128-CBC decrypt
{
// Create crypto script with 5 instructions
cs0begin(0x05);
cxsin($c3); // Read 0x10 bytes from crypto stream into c3
cdec($c2, $c3); // Decrypt from c3 into c2
cxor($c5, $c2); // XOR c2 with c5 and store in c5
cxsout($c5); // Write 0x10 bytes into crypto stream from c5
cmov($c5, $c3); // Move c3 into c5
}
else if (mode == 0x01) // AES-128-CBC encrypt
{
// Create crypto script with 4 instructions
cs0begin(0x04);
cxsin($c3); // Read 0x10 bytes from crypto stream into c3
cxor($c3, $c5); // XOR c5 with c3 and store in c3
cenc($c5, $c3); // Encrypt from c3 into c5
cxsout($c5); // Write 0x10 bytes into crypto stream from c5
}
else if (mode == 0x02) // AES-CMAC
{
// Create crypto script with 3 instructions
cs0begin(0x03);
cxsin($c3); // Read 0x10 bytes from crypto stream into c3
cxor($c5, $c3); // XOR c5 with c3 and store in c5
cenc($c5, $c5); // Encrypt from c5 into c5
}
else if (mode == 0x03) // AES-128-ECB decrypt
{
// Create crypto script with 3 instructions
cs0begin(0x03);
cxsin($c3); // Read 0x10 bytes from crypto stream into c3
cdec($c5, $c3); // Decrypt from c3 into c5
cxsout($c5); // Write 0x10 bytes into crypto stream from c5
}
else if (mode == 0x04) // AES-128-ECB encrypt
{
// Create crypto script with 3 instructions
cs0begin(0x03);
cxsin($c3); // Read 0x10 bytes from crypto stream into c3
cenc($c5, $c3); // Encrypt from c3 into c5
cxsout($c5); // Write 0x10 bytes into crypto stream from c5
}
else
return;
// Main loop
while (src_size > 0)
{
u32 blk_count = (src_size >> 0x04);
if (blk_count > 0x10)
blk_count = 0x10;
// Check size align
if (blk_count & (blk_count - 0x01))
blk_count = 0x01;
u32 blk_size = (blk_count << 0x04);
u32 crypto_xfer_src = 0;
u32 crypto_xfer_dst = 0;
if (block_size == 0x20)
{
crypto_xfer_src = (0x00030000 | src_addr);
crypto_xfer_dst = (0x00030000 | dst_addr);
// Execute crypto script 2 times (1 for each block)
cs0exec(0x02);
}
else if (block_size == 0x40)
{
crypto_xfer_src = (0x00040000 | src_addr);
crypto_xfer_dst = (0x00040000 | dst_addr);
// Execute crypto script 4 times (1 for each block)
cs0exec(0x04);
}
else if (block_size == 0x80)
{
crypto_xfer_src = (0x00050000 | src_addr);
crypto_xfer_dst = (0x00050000 | dst_addr);
// Execute crypto script 8 times (1 for each block)
cs0exec(0x08);
}
else if (block_size == 0x100)
{
crypto_xfer_src = (0x00060000 | src_addr);
crypto_xfer_dst = (0x00060000 | dst_addr);
// Execute crypto script 16 times (1 for each block)
cs0exec(0x10);
}
else
{
crypto_xfer_src = (0x00020000 | src_addr);
crypto_xfer_dst = (0x00020000 | dst_addr);
// Execute crypto script 1 time (1 for each block)
cs0exec(0x01);
// Ensure proper block size
block_size = 0x10;
}
// The next xfer instruction will be overridden
// and target changes from DMA to crypto input/output stream
if (use_imem)
cxset(0xA1); // Flag 0xA0 is falcon imem <-> crypto input/output stream
else
cxset(0x21); // Flag 0x20 is external mem <-> crypto input/output stream
// Transfer data into the crypto input/output stream
xdst(crypto_xfer_src, crypto_xfer_src);
// AES-CMAC only needs one more xfer instruction
if (mode == 0x02)
{
// The next xfer instruction will be overridden
// and target changes from DMA to crypto input/output stream
if (use_imem)
cxset(0xA1); // Flag 0xA0 is falcon imem <-> crypto input/output stream
else
cxset(0x21); // Flag 0x20 is external mem <-> crypto input/output stream
// Wait for all data loads/stores to finish
xdwait();
}
else // AES enc/dec needs 2 more xfer instructions
{
// The next 2 xfer instructions will be overridden
// and target changes from DMA to crypto input/output stream
if (use_imem)
cxset(0xA2); // Flag 0xA0 is falcon imem <-> crypto input/output stream
else
cxset(0x22); // Flag 0x20 is external mem <-> crypto input/output stream
// Transfer data from the crypto input/output stream
xdld(crypto_xfer_dst, crypto_xfer_dst);
// Wait for all data loads/stores to finish
xdwait();
// Increase the destination address by block size
dst_addr += block_size;
}
// Increase the source address by block size
src_addr += block_size;
// Decrease the source size by block size
src_size -= block_size;
}
// AES-CMAC result is in c5
if (mode == 0x02)
{
// This will read into dst_addr from crypto register c5
crypto_load(0x05, dst_addr);
}
return;
Keygen
This stage is decrypted by KeygenLdr using a key generated by encrypting the KeygenLdr auth signature with a seed encrypted with a csecret. It will generate the final TSEC key.
Main
The main function takes key_addr and key_type as arguments from KeygenLdr.
u32 falcon_rev = *(u32 *)FALCON_HWCFG2 & 0x0F;
// Falcon hardware revision must be 5
if (falcon_revĀ != 0x05)
exit();
// Clear interrupt flags
$flags.ie0 = 0;
$flags.ie1 = 0;
$flags.ie2 = 0;
// Set the target port for memory transfers
$xtargets = 0;
// Generate the TSEC key
gen_tsec_key(key_addr, key_type);
// Clear the cauth signature
csigclr();
// Clear all crypto registers
cxor($c0, $c0);
cxor($c1, $c1);
cxor($c2, $c2);
cxor($c3, $c3);
cxor($c4, $c4);
cxor($c5, $c5);
cxor($c6, $c6);
cxor($c7, $c7);
return;
gen_tsec_key
This method is responsible for generating the final TSEC key. It takes key_addr and key_type as arguments.
// This will use TSEC DMA to look for 0x34C2E1DA in host1x scratch space
u32 host1x_res = check_host1x_magic();
// Failed to find magic word
if (host1x_resĀ != 0)
return;
u32 crypto_reg_flag = 0x00000000;
// The next 0x02 xfer instructions will be overridden
// and target changes from DMA to crypto register
cxset(0x02);
// Transfer the seed in key_addr to crypto register c0
xdst(0, (key_addr | crypto_reg_flag));
// Wait for all data loads/stores to finish
xdwait();
crypto_reg_flag = 0x00020000;
if (key_type == 0x01) // HOVI_EKS_01
{
// Load selected secret into crypto register c1
csecret($c1, 0x3F);
// Encrypt the auth signature with c1 and store in c1
csigenc($c1, $c1);
// Load selected secret into crypto register c2
csecret($c2, 0x00);
// Bind c2 register as the key for enc/dec operations
ckeyreg($c2);
// Encrypt the seed from key_addr and store in c2
cenc($c2, $c0);
// Bind c2 register as the key for enc/dec operations
ckeyreg($c2);
// Encrypt the auth signature with c2 and store in c2
csigenc($c2, $c2);
// Bind c2 register as the key for enc/dec operations
ckeyreg($c2);
// Encrypt c1 and store in c2
cenc($c2, $c1);
// The next 0x02 xfer instructions will be overridden
// and target changes from DMA to crypto register
cxset(0x02);
// Transfer the resulting key from crypto register c2 to key_addr
xdld(0, (key_addr | crypto_reg_flag));
// Wait for all data loads/stores to finish
xdwait();
}
else if (key == 0x02) // HOVI_COMMON_01
{
// Load selected secret into crypto register c2
csecret($c2, 0x00);
// Bind c2 register as the key for enc/dec operations
ckeyreg($c2);
// Encrypt the seed from key_addr and store in c2
cenc($c2, $c0);
// Bind c2 register as the key for enc/dec operations
ckeyreg($c2);
// Encrypt the auth signature with c2 and store in c2
csigenc($c2, $c2);
// The next 0x02 xfer instructions will be overridden
// and target changes from DMA to crypto register
cxset(0x02);
// Transfer the resulting key from crypto register c2 to key_addr
xdld(0, (key_addr | crypto_reg_flag));
// Wait for all data loads/stores to finish
xdwait();
}
// Use TSEC DMA to write the key in SOR1 registers
sor1_set_key(key_addr);
return;
sor1_set_key
This method takes key_addr (start address of a 16 bytes buffer) as argument and transfers its contents to SOR1 registers.
The implementation is equivalent to tsec_set_key.
SecureBootLdr
[6.2.0+] This was introduced to try to recover the secure boot from the RCM vulnerability.
This stage starts by authenticating and executing KeygenLdr which in turn authenticates, decrypts and executes Keygen (both blobs remain unchanged from previous firmware versions). After the TSEC key has been generated, execution returns to this stage which then parses and executes SecureBoot.
Main
u8 key_data_buf[0x84];
u8 tmp_key_data_buf[0x84];
// Read the key data from memory
u32 key_data_addr = 0x300;
u32 key_data_size = 0x84;
memcpy_i2d(key_data_buf, key_data_addr, key_data_size);
// Read the KeygenLdr blob from memory
u32 boot_base_addr = 0;
u32 blob1_addr = 0x400;
u32 blob1_size = *(u32 *)(key_data_buf + 0x74);
memcpy_i2d(boot_base_addr, blob1_addr, blob1_size);
// Upload the next code segment into Falcon's CODE region
u32 blob1_virt_addr = 0x300;
bool use_secret = true;
memcpy_d2i(blob1_virt_addr, boot_base_addr, blob1_size, blob1_virt_addr, use_secret);
// Backup the key data
memcpy(tmp_key_data_buf, key_data_buf, 0x84);
// Save previous cauth value
u32 cauth_old = $cauth;
// Set auth_addr to 0x300 and auth_size to blob1_size
$cauth = ((blob1_size << 0x10) | (0x300 >> 0x08));
// The next 2 xfer instructions will be overridden
// and target changes from DMA to crypto
cxset(0x02);
u32 crypto_reg_flag = 0x00060000;
u32 blob1_hash_addr = tmp_key_data_buf + 0x20;
// Transfer data to crypto register c6
xdst(0, (blob1_hash_addr | crypto_reg_flag));
// Wait for all data loads/stores to finish
xdwait();
u32 key_version = 0x01;
bool is_blob_dec = false;
// Jump to KeygenLdr
u32 keygenldr_res = exec_keygenldr(tmp_key_data_buf, key_version, is_blob_dec);
// Set boot finish magic on success
if (keygenldr_res == 0)
keygenldr_res = 0xB0B0B0B0
// Write result to FALCON_SCRATCH1
*(u32 *)FALCON_SCRATCH1 = keygenldr_res;
if (keygenldr_resĀ != 0xB0B0B0B0)
return keygenldr_res;
// Restore previous cauth value
$cauth = cauth_old;
u8 flcn_hdr_buf[0x18];
u8 flcn_os_hdr_buf[0x10];
blob1_size = *(u32 *)(key_data_buf + 0x74);
u32 blob2_size = *(u32 *)(key_data_buf + 0x78);
u32 blob0_size = *(u32 *)(key_data_buf + 0x70);
// Read the SecureBoot blob's Falcon header from memory
u32 blob4_flcn_hdr_addr = (((blob0_size + blob1_size) + 0x100) + blob2_size);
memcpy_i2d(flcn_hdr_buf, blob4_flcn_hdr_addr, 0x18);
blob1_size = *(u32 *)(key_data_buf + 0x74);
blob2_size = *(u32 *)(key_data_buf + 0x78);
blob0_size = *(u32 *)(key_data_buf + 0x70);
u32 flcn_hdr_size = *(u32 *)(flcn_hdr_buf + 0x0C);
// Read the SecureBoot blob's Falcon OS header from memory
u32 blob4_flcn_os_hdr_addr = ((((blob0_size + blob1_size) + 0x100) + blob2_size) + flcn_hdr_size);
memcpy_i2d(flcn_os_hdr_buf, blob4_flcn_os_hdr_addr, 0x10);
blob1_size = *(u32 *)(key_data_buf + 0x74);
blob2_size = *(u32 *)(key_data_buf + 0x78);
blob0_size = *(u32 *)(key_data_buf + 0x70);
u32 flcn_code_hdr_size = *(u32 *)(flcn_hdr_buf + 0x10);
u32 flcn_os_size = *(u32 *)(flcn_os_hdr_buf + 0x04);
// Read the SecureBoot blob's Falcon OS image from memory
u32 blob4_flcn_os_addr = ((((blob0_size + blob1_size) + 0x100) + blob2_size) + flcn_code_hdr_size);
memcpy_i2d(boot_base_addr, blob4_flcn_os_addr, flcn_os_size);
// Upload the SecureBoot's Falcon OS image boot stub code segment into Falcon's CODE region
u32 blob4_flcn_os_boot_virt_addr = 0;
u32 blob4_flcn_os_boot_size = 0x100;
use_secret = false;
memcpy_d2i(blob4_flcn_os_boot_virt_addr, boot_base_addr, blob4_flcn_os_boot_size, blob4_flcn_os_boot_virt_addr, use_secret);
flcn_os_size = *(u32 *)(flcn_os_hdr_buf + 0x04);
// Upload the SecureBoot blob's Falcon OS encrypted image code segment into Falcon's CODE region
u32 blob4_flcn_os_img_virt_addr = 0x100;
u32 blob4_flcn_os_img_size = (flcn_os_size - 0x100);
use_secret = true;
memcpy_d2i(blob4_flcn_os_img_virt_addr, boot_base_addr + 0x100, blob4_flcn_os_img_size, blob4_flcn_os_img_virt_addr, use_secret);
// Wait for all code loads to finish
xcwait();
blob1_size = *(u32 *)(key_data_buf + 0x74);
blob2_size = *(u32 *)(key_data_buf + 0x78);
blob0_size = *(u32 *)(key_data_buf + 0x70);
flcn_code_hdr_size = *(u32 *)(flcn_hdr_buf + 0x10);
u32 flcn_os_code_size = *(u32 *)(flcn_os_hdr_buf + 0x08);
// Read the SecureBoot blob's falcon OS image's hash from memory
u32 blob4_flcn_os_img_hash_addr = (((((blob0_size + blob1_size) + 0x100) + blob2_size) + flcn_code_hdr_size) + flcn_os_code_size);
memcpy_i2d(0, blob4_flcn_os_img_hash_addr, 0x10);
// Read data segment size from IO space
u32 data_seg_size = *(u32 *)FALCON_HWCFG;
data_seg_size >>= 0x03;
data_seg_size &= 0x3FC0;
u32 data_addr = 0x10;
// Clear all data except the first 0x10 bytes (SecureBoot blob's Falcon OS image's hash)
for (int data_word_count = 0x04; data_word_count < data_seg_size; data_word_count++)
{
*(u32 *)(data_addr) = 0;
data_addr += 0x04;
}
// Clear all crypto registers
cxor($c0, $c0);
cxor($c1, $c1);
cxor($c2, $c2);
cxor($c3, $c3);
cxor($c4, $c4);
cxor($c5, $c5);
cxor($c6, $c6);
cxor($c7, $c7);
// Clear the cauth signature
csigclr();
// Jump to SecureBoot
load_secboot();
return 0xB0B0B0B0;
SecureBoot
[6.2.0+] This was introduced to try to recover the secure boot from the RCM vulnerability.
This stage prepares the stack then authenticates, decrypts and executes the SecureBoot blob's Falcon OS image.
Main
// Read data segment size from IO space
u32 data_seg_size = *(u32 *)FALCON_HWCFG;
data_seg_size >>= 0x01;
data_seg_size &= 0xFF00;
// Set the stack pointer
$sp = data_seg_size;
// Jump to the SecureBoot blob's Falcon OS image boot stub
init_secboot();
// Halt execution
exit();
return;
init_secboot
This method takes no arguments and is responsible for loading, authenticating and executing SecureBoot.
// Read the transfer base address from IO space
u32 xfer_ext_base_addr = *(u32 *)FALCON_DMATRFBASE;
// Copy transfer base address to data memory
u32 scratch_data_addr = 0x300;
*(u32 *)scratch_data_addr = xfer_ext_base_addr;
// Set the transfer base address
xcbase(xfer_ext_base_addr);
// The next xfer instruction will be overridden
// and target changes from DMA to crypto
cxset(0x01);
u32 crypto_reg_flag = 0x00060000;
u32 blob4_flcn_os_img_hash_addr = 0;
// Transfer data to crypto register c6
xdst(0, (blob4_flcn_os_img_hash_addr | crypto_reg_flag));
// The next xfer instruction will be overridden
// and target changes from DMA to crypto
cxset(0x01);
// Wait for all data loads/stores to finish
xdwait();
cmov($c7, $c6);
cxor($c7, $c7);
// Set auth_addr to 0x100, auth_size to 0x1300,
// bit 16 (use_secret) and bit 17 (is_encrypted)
$cauth = ((0x02 << 0x10) | (0x01 << 0x10) | (0x1300 << 0x10) | (0x100 >> 0x08));
// Clear interrupt flags
$flags.ie0 = 0;
$flags.ie1 = 0;
$flags.ie2 = 0;
// Jump to the SecureBoot blob's Falcon OS image
exec_secboot();
return 0x0F0F0F0F;
[8.1.0+] Removed transfer base address setting and added IMEM protection.
// The next xfer instruction will be overridden
// and target changes from DMA to crypto
cxset(0x01);
u32 crypto_reg_flag = 0x00060000;
u32 blob4_flcn_os_img_hash_addr = 0;
// Transfer data to crypto register c6
xdst(0, (blob4_flcn_os_img_hash_addr | crypto_reg_flag));
// The next xfer instruction will be overridden
// and target changes from DMA to crypto
cxset(0x01);
// Wait for all data loads/stores to finish
xdwait();
cmov($c7, $c6);
cxor($c7, $c7);
// Set auth_addr to 0x100, auth_size to 0x1D00,
// bit 16 (use_secret) and bit 17 (is_encrypted)
$cauth = ((0x02 << 0x10) | (0x01 << 0x10) | (0x1D00 << 0x10) | (0x100 >> 0x08));
// Clear interrupt flags
$flags.ie0 = 0;
$flags.ie1 = 0;
$flags.ie2 = 0;
// Fill remaining IMEM with secret pages
bool use_secret = true;
memcpy_d2i(0x1E00, 0, 0x2200, 0x1E00, use_secret);
memcpy_d2i(0x4000, 0, 0x4000, 0x4000, use_secret);
// Wait for all code loads to finish
xcwait();
// Jump to the SecureBoot blob's Falcon OS image
exec_secboot();
return 0x0F0F0F0F;
exec_secboot
This is the signed and encrypted portion of the SecureBoot payload.
// Recover the transfer base address from the stack
u32 xfer_ext_base_addr = *(u32 *)scratch_data_addr;
// Return the TLB entry that covers the virtual address
u32 tlb_entry = vtlb(xfer_ext_base_addr);
// Clear Falcon CPU control
*(u32 *)FALCON_CPUCTL = 0;
// Halt if the external page is marked as secret
if ((tlb_entry & 0x4000000)Ā != 0)
exit();
// Read data segment size from IO space
u32 data_seg_size = *(u32 *)FALCON_HWCFG;
data_seg_size >>= 0x01;
data_seg_size &= 0xFF00;
// Set the stack pointer
$sp = data_seg_size;
// Fill all DMEM with a pointer to a trap function (just exits 3 times)
for (int i = 0; i < data_seg_size; i += 0x04) {
*(u32 *)i = (u32)trap_func();
}
// Initialize the TRNG and generate random data in DMEM
init_rnd();
// Issue a randomized delay and return a random value
u32 rnd_val = rnd_delay(0xFF);
// Load the TSEC key from SOR1 registers into DMEM
sor1_get_key();
// Initialize CAR registers
car_init();
// Check certain CAR, PMC and FUSE registers
test_car_pmc_fuse();
// Ensure CLK_RST_CONTROLLER_CLK_SOURCE_TSEC_0 is 0x02
test_clk_source_tsec();
// Set FLOW_MODE_WAITEVENT in FLOW_CTLR_HALT_COP_EVENTS_0
halt_bpmp();
// Initialize the CCPLEX
ccplex_init();
// Check certain CAR, PMC and FUSE registers
test_car_pmc_fuse();
bool is_se_ready = false;
// Wait for SE to be ready
while (!is_se_ready)
is_se_ready = check_se_status();
// Test MC_IRAM_BOM and MC_IRAM_TOM
u32 mc_iram_aperture_res = test_mc_iram_aperture();
if (mc_iram_aperture_resĀ != 0xAAAAAAAA)
{
// Clear the entire DMEM region
clear_dmem();
// Halt 5 times for no good reason
exit();
exit();
exit();
exit();
exit();
}
// Ensure FUSE_SKU_INFO is 0x83
test_fuse_sku_info();
// Write TSEC key to SE keyslot 0x0C
se_set_keyslot_12();
// Write TSEC root key to SE keyslot 0x0D
se_set_keyslot_13();
// Decrypt Package1
decrypt_pk11();
// Check certain CAR, PMC and FUSE registers
test_car_pmc_fuse();
// Parse Package1 header and return entry address
u32 entry_addr = parse_pk11();
// Set the exception vectors
set_excp_vec(entry_addr);
// Fill the top 0x500 bytes in DMEM with a pointer to trap function (just exits 3 times)
for (int i = 0; i < 0x500; i += 0x04) {
*(u32 *)i = (u32)trap_func();
}
// Clear all crypto registers
cxor($c0, $c0);
cxor($c1, $c1);
cxor($c2, $c2);
cxor($c3, $c3);
cxor($c4, $c4);
cxor($c5, $c5);
cxor($c6, $c6);
cxor($c7, $c7);
// Take SCP out of lockdown
unlock_scp();
// Clear FLOW_CTLR_HALT_COP_EVENTS_0
resume_bpmp();
// Clear the entire DMEM region
clear_dmem();
// Halt 5 times for no good reason
exit();
exit();
exit();
exit();
exit();
return;
[7.0.0+] Many changes were introduced to mitigate and prevent attacks.
// Recover the transfer base address from the stack
u32 xfer_ext_base_addr = *(u32 *)scratch_data_addr;
// Return the TLB entry that covers the virtual address
u32 tlb_entry = vtlb(xfer_ext_base_addr);
// Clear Falcon CPU control
*(u32 *)FALCON_CPUCTL = 0;
// Halt if the external page is marked as secret
if ((tlb_entry & 0x4000000)Ā != 0)
exit();
// Read data segment size from IO space
u32 data_seg_size = *(u32 *)FALCON_HWCFG;
data_seg_size >>= 0x01;
data_seg_size &= 0xFF00;
// Set the stack pointer
$sp = data_seg_size;
// Fill all DMEM with a pointer to a trap function (just exits 3 times)
for (int i = 0; i < data_seg_size; i += 0x04) {
*(u32 *)i = (u32)trap_func();
}
// Initialize the TRNG and generate random data in DMEM
init_rnd();
// Issue a randomized delay and return a random value
u32 rnd_val = rnd_delay(0xFF);
// Enable and test SMMU bypassing in the TFBIF
tfbif_smmu_cfg(0x01);
// Issue a randomized delay and return a random value
rnd_val = rnd_delay(0xFF);
// Test SMMU bypassing in the TFBIF
tfbif_smmu_cfg(0x00);
// Issue a randomized delay and return a random value
rnd_val = rnd_delay(0xFF);
// Test SMMU bypassing in the TFBIF
tfbif_smmu_cfg(0x00);
// Fill SE keyslots 12 and 13 with random data
se_set_keyslot_rnd();
// Test randomized offsets for read/write integrity in MC, FUSE, IRAM and TZRAM
u32 test_res = test_mc_fuse_iram_tzram();
if (test_resĀ != 0xAAAAAAAA)
{
// Fill SE keyslots 12 and 13 with random data
se_set_keyslot_rnd();
// Clear the entire DMEM region and every crypto register
clear_dmem_and_crypto();
// Halt 5 times for no good reason
exit();
exit();
exit();
exit();
exit();
}
// Try to detect virtualization by enabling and disabling random CAR devices
test_res = test_car();
if (test_resĀ != 0xAAAAAAAA)
{
// Fill SE keyslots 12 and 13 with random data
se_set_keyslot_rnd();
// Clear the entire DMEM region and every crypto register
clear_dmem_and_crypto();
// Halt 5 times for no good reason
exit();
exit();
exit();
exit();
exit();
}
// Test memory transfer integrity
test_res = test_mem_xfer();
if (test_resĀ != 0xAAAAAAAA)
{
// Fill SE keyslots 12 and 13 with random data
se_set_keyslot_rnd();
// Clear the entire DMEM region and every crypto register
clear_dmem_and_crypto();
// Halt 5 times for no good reason
exit();
exit();
exit();
exit();
exit();
}
// Set FLOW_MODE_WAITEVENT in FLOW_CTLR_HALT_COP_EVENTS_0
halt_bpmp();
// Initialize the CCPLEX
ccplex_init();
// Check if SE is ready
u32 se_status = check_se_status();
if (se_statusĀ != 0)
{
// Fill SE keyslots 12 and 13 with random data
se_set_keyslot_rnd();
// Clear the entire DMEM region and every crypto register
clear_dmem_and_crypto();
// Halt 5 times for no good reason
exit();
exit();
exit();
exit();
exit();
}
// Load the TSEC key from SOR1 registers into DMEM
sor1_get_key();
// Initialize CAR registers
car_init();
// Check certain CAR, PMC and FUSE registers
test_car_pmc_fuse();
// Try to detect virtualization by enabling and disabling random CAR devices
test_res = test_car();
if (test_resĀ != 0xAAAAAAAA)
{
// Fill SE keyslots 12 and 13 with random data
se_set_keyslot_rnd();
// Clear the entire DMEM region and every crypto register
clear_dmem_and_crypto();
// Halt 5 times for no good reason
exit();
exit();
exit();
exit();
exit();
}
// Ensure FUSE_SKU_INFO is 0x83
test_fuse_sku_info();
// Try to detect virtualization using MC_SMMU_AVPC_ASID and FUSE_ECO_RESERVE_0
test_smmu_fuse();
// Test MC_IRAM_BOM and MC_IRAM_TOM
test_res = test_mc_iram_aperture();
if (test_resĀ != 0xAAAAAAAA)
{
// Fill SE keyslots 12 and 13 with random data
se_set_keyslot_rnd();
// Clear the entire DMEM region and every crypto register
clear_dmem_and_crypto();
// Halt 5 times for no good reason
exit();
exit();
exit();
exit();
exit();
}
// Check certain CAR, PMC and FUSE registers
test_car_pmc_fuse();
// Test memory transfer integrity
test_res = test_mem_xfer();
if (test_resĀ != 0xAAAAAAAA)
{
// Fill SE keyslots 12 and 13 with random data
se_set_keyslot_rnd();
// Clear the entire DMEM region and every crypto register
clear_dmem_and_crypto();
// Halt 5 times for no good reason
exit();
exit();
exit();
exit();
exit();
}
// Try to detect virtualization using MC_SMMU_AVPC_ASID and FUSE_ECO_RESERVE_0
test_smmu_fuse();
// Test MC_IRAM_BOM and MC_IRAM_TOM
test_res = test_mc_iram_aperture();
if (test_resĀ != 0xAAAAAAAA)
{
// Fill SE keyslots 12 and 13 with random data
se_set_keyslot_rnd();
// Clear the entire DMEM region and every crypto register
clear_dmem_and_crypto();
// Halt 5 times for no good reason
exit();
exit();
exit();
exit();
exit();
}
// Test SMMU bypassing in the TFBIF
tfbif_smmu_cfg(0x00);
// Decrypt Package1
decrypt_pk11();
// Write TSEC root key to SE keyslot 0x0D
se_set_keyslot_13();
// Write TSEC key to SE keyslot 0x0C
se_set_keyslot_12();
// Clear the cauth signature
csigclr();
// Check certain CAR, PMC and FUSE registers
test_car_pmc_fuse();
// Test memory transfer integrity
test_res = test_mem_xfer();
if (test_resĀ != 0xAAAAAAAA)
{
// Fill SE keyslots 12 and 13 with random data
se_set_keyslot_rnd();
// Clear the entire DMEM region and every crypto register
clear_dmem_and_crypto();
// Halt 5 times for no good reason
exit();
exit();
exit();
exit();
exit();
}
// Try to detect virtualization using MC_SMMU_AVPC_ASID and FUSE_ECO_RESERVE_0
test_smmu_fuse();
// Test randomized offsets for read/write integrity in MC, FUSE, IRAM and TZRAM
test_res = test_mc_fuse_iram_tzram();
if (test_resĀ != 0xAAAAAAAA)
{
// Fill SE keyslots 12 and 13 with random data
se_set_keyslot_rnd();
// Clear the entire DMEM region and every crypto register
clear_dmem_and_crypto();
// Halt 5 times for no good reason
exit();
exit();
exit();
exit();
exit();
}
// Test MC_IRAM_BOM and MC_IRAM_TOM
test_res = test_mc_iram_aperture();
if (test_resĀ != 0xAAAAAAAA)
{
// Fill SE keyslots 12 and 13 with random data
se_set_keyslot_rnd();
// Clear the entire DMEM region and every crypto register
clear_dmem_and_crypto();
// Halt 5 times for no good reason
exit();
exit();
exit();
exit();
exit();
}
// Test SMMU bypassing in the TFBIF
tfbif_smmu_cfg(0x00);
// Parse Package1 header and return entry address
u32 entry_addr = parse_pk11();
// Set the exception vectors
set_excp_vec(entry_addr);
// Fill the top 0x500 bytes in DMEM with a pointer to trap function (just exits)
for (int i = 0; i < 0x500; i += 0x04) {
*(u32 *)i = (u32)trap_func();
}
// Clear all crypto registers
cxor($c0, $c0);
cxor($c1, $c1);
cxor($c2, $c2);
cxor($c3, $c3);
cxor($c4, $c4);
cxor($c5, $c5);
cxor($c6, $c6);
cxor($c7, $c7);
// Take SCP out of lockdown
unlock_scp();
// Test memory transfer integrity
test_res = test_mem_xfer();
if (test_resĀ != 0xAAAAAAAA)
{
// Fill SE keyslots 12 and 13 with random data
se_set_keyslot_rnd();
// Clear the entire DMEM region and every crypto register
clear_dmem_and_crypto();
// Halt 5 times for no good reason
exit();
exit();
exit();
exit();
exit();
}
// Try to detect virtualization using MC_SMMU_AVPC_ASID and FUSE_ECO_RESERVE_0
test_smmu_fuse();
// Test MC_IRAM_BOM and MC_IRAM_TOM
test_res = test_mc_iram_aperture();
if (test_resĀ != 0xAAAAAAAA)
{
// Fill SE keyslots 12 and 13 with random data
se_set_keyslot_rnd();
// Clear the entire DMEM region and every crypto register
clear_dmem_and_crypto();
// Halt 5 times for no good reason
exit();
exit();
exit();
exit();
exit();
}
// Test SMMU bypassing in the TFBIF
tfbif_smmu_cfg(0x00);
// Clear FLOW_CTLR_HALT_COP_EVENTS_0
resume_bpmp();
// Clear the entire DMEM region and every crypto register
clear_dmem_and_crypto();
// Halt 5 times for no good reason
exit();
exit();
exit();
exit();
exit();
return;
[8.1.0+] Key derivation algorithm was changed. Very minor changes were introduced to mitigate and prevent attacks.
Key data
Small buffer stored after the Boot blob and used across all stages.
| Offset | Size | Description |
|---|---|---|
| 0x00 | 0x10 | Debug key (empty) |
| 0x10 | 0x10 | blob0 (Boot) auth hash |
| 0x20 | 0x10 | blob1 (KeygenLdr) auth hash |
| 0x30 | 0x10 | blob2 (Keygen) auth hash |
| 0x40 | 0x10 | blob2 (Keygen) AES IV |
| 0x50 | 0x10 | HOVI EKS seed |
| 0x60 | 0x10 | HOVI COMMON seed |
| 0x70 | 0x04 | blob0 (Boot) size |
| 0x74 | 0x04 | blob1 (KeygenLdr) size |
| 0x78 | 0x04 | blob2 (Keygen) size |
| 0x7C | 0x04 | [6.2.0+] blob3 (SecureBootLdr) size |
| 0x80 | 0x04 | [6.2.0+] blob4 (SecureBoot) size |