Upgrading version to 1.4.

Signed-off-by: Pol Henarejos <pol.henarejos@cttc.es>

CMakeLists.txt

@@ -82,6 +82,7 @@ target_sources(pico_openpgp PUBLIC
         ${CMAKE_CURRENT_LIST_DIR}/pico-ccid/mbedtls/library/des.c
         ${CMAKE_CURRENT_LIST_DIR}/pico-ccid/mbedtls/library/nist_kw.c
         ${CMAKE_CURRENT_LIST_DIR}/pico-ccid/mbedtls/library/hkdf.c
+        ${CMAKE_CURRENT_LIST_DIR}/pico-ccid/mbedtls/library/asn1parse.c
         )
 
 target_include_directories(pico_openpgp PUBLIC

README.md

@@ -0,0 +1,121 @@
+# Pico OpenPGP
+This project aims at transforming your Raspberry Pico into a Smart Card with an OpenPGP applet integrated. The Pico works as a reader with an embedded OpenPGP card, like a USB card.
+
+OpenPGP cards are used to manage PGP keys and do cryptographic operations, such as keypair generation, signing and asymmetric deciphering. Pico OpenPGP follows the [**OpenPGP 3.4.1** specifications](https://gnupg.org/ftp/specs/OpenPGP-smart-card-application-3.4.pdf "**OpenPGP 3.4.1** specifications"), available at [GnuPG](http://gnupg.org "GnuPG").
+
+## Features
+Pico OpenPGP has implemented the following features:
+
+- Key generation and encrypted storage.
+- RSA key generation from 1024 to 4096 bits.
+- ECDSA key generation from 192 to 521 bits.
+- ECC curves secp256r1, secp384r1, secp521r1, brainpoolP256r1, brainpoolP384r1, brainpoolP512r1, secp256k1.
+- SHA1, SHA224, SHA256, SHA384, SHA512 digests.
+- RSA-PKCS and raw RSA signature.
+- ECDSA raw and hash signature.
+- ECDH key derivation.
+- PIN authorization.
+- PKCS11 compliant interface.
+- HRNG (hardware random number generator).
+- Device Encryption Key (DEK).
+- USB/CCID support with OpenSC, openssl, etc.
+- Extended APDU support.
+- Lifecycle card (termination and activation).
+
+All these features are compliant with the specification. Therefore, if you detect some behaviour that is not expected or it does not follow the rules of specs, please open an issue.
+
+### About Gnuk
+This project was inspired by [Gnuk](https://wiki.debian.org/GNUK "Gnuk"), a same project but focused on STM32 processor family. Despite the initial idea was to port Gnuk to the Raspberry Pico family, the underlaying architecture is widely different (although they run on ARM). For instance, the Pico has two ARM cores, with an appropiate SDK able to leverage them. Also, Pico has an internal flash storage, which is farly larger compared to STM32 ROM storage. Finally, the Pico has a complete USB interface based on TinyUSB, which difficults to port Gnuk. These are only few examples of the difficulties of porting Gnuk to the Raspberry Pico.
+
+As a consequence, Pico OpenPGP is designed from zero. Well, not strictly from zero, as it borrows some of the buffering between USB and CCID interfaces from Gnuk. Cryptographic operations are implemented with MBEDTLS library.
+
+## Security considerations
+All secret keys (asymmetric and symmetric) are stored encrypted in the flash memory of the Raspberry Pico. DEK is used as a 256 bit AES key to protect private and secret keys. Keys are never stored in RAM except for signature and decryption operations and only during the process. All keys (including DEK) are loaded and cleared every time to avoid potential security flaws.
+
+At the same time, DEK is encrypted with doubled salted and hashed PIN. Also, the PIN is hashed in memory during the session. Hence, PIN is never stored in plain text neither in flash nor in memory. Note that PIN is conveyed from the host to the Pico in plain text if no secure channel is provided.
+
+If the Pico is stolen the contents of private and secret keys cannot be read without the PIN, even if the flash memory is dumped.
+
+## Download
+Please, go to the [Release page](https://github.com/polhenarejos/pico-openpgp/releases "Release page"))  and download the UF2 file for your board.
+
+Note that UF2 files are shiped with a dummy VID/PID to avoid license issues (FEFF:FCFD). If you are planning to use it with OpenSC or similar, you should modify Info.plist of CCID driver to add these VID/PID or use the VID/PID patcher as follows: `./patch_vidpid.sh VID:PID input_openpgp_file.uf2 output_openpgp_file.uf2`
+
+You can use whatever VID/PID (i.e., 234b:0000 from FISJ), but remember that you are not authorized to distribute the binary with a VID/PID that you do not own.
+
+## Build
+Before building, ensure you have installed the toolchain for the Pico and the Pico SDK is properly located in your drive.
+
+    git clone https://github.com/polhenarejos/pico-openpgp
+    cd pico-openpgp
+    mkdir build
+    cd build
+    PICO_SDK_PATH=/path/to/pico-sdk cmake .. -DPICO_BOARD=board_type -DUSB_VID=0x1234 -DUSB_PID=0x5678
+    make
+
+Note that PICO_BOARD, USB_VID and USB_PID are optional. If not provided, pico board and VID/PID FEFF:FCFD will be used.
+
+After make ends, the binary file pico_openpgp.uf2 will be generated. Put your pico board into loading mode, by pushing BOOTSEL button while pluging on, and copy the UF2 to the new fresh usb mass storage Pico device. Once copied, the pico mass storage will be disconnected automatically and the pico board will reset with the new firmware. A blinking led will indicate the device is ready to work.
+
+## Operation time
+### Keypair generation
+Generating EC keys is almost instant. RSA keypair generation takes some time, specially for 3072 and 4096 bits.
+### Keypair generation
+Generating EC keys is almost instant. RSA keypair generation takes some time, specially for `3072` and `4096` bits. 
+
+| RSA key length (bits) | Average time (seconds) |
+| :---: | :---: |
+| 1024 | 16 |
+| 2048 | 124 |
+| 3072 | 600 |
+| 4096 | ~1000 |
+
+### Signature and decrypt
+| RSA key length (bits) | Average time (seconds) |
+| :---: | :---: |
+| 1024 | 1 |
+| 2048 | 3 |
+| 3072 | 7 |
+| 4096 | 15 |
+
+## Led blink
+Pico OpenPGP uses the led to indicate the current status. Four states are available:
+### Press to confirm
+The Led is almost on all the time. It goes off for 100 miliseconds every second.
+
+![Press to confirm](https://user-images.githubusercontent.com/55573252/162008917-6a730eac-396c-44cc-890e-802294be30a3.gif)
+
+### Idle mode
+In idle mode, the Pico OpenPGP goes to sleep. It waits for a command and it is awaken by the driver. The Led is almost off all the time. It goes on for 500 milliseconds every second.
+
+![Idle mode](https://user-images.githubusercontent.com/55573252/162008980-d5a5caad-072e-400c-98e3-2c606b4b2af9.gif)
+
+### Active mode
+In active mode, the Pico OpenPGP is awaken and ready to receive a command. It blinks four times in a second.
+
+![Active](https://user-images.githubusercontent.com/55573252/162008997-1ea8cd7e-5384-4893-9dcb-b473153fc375.gif)
+
+### Processing
+While processing, the Pico OpenPGP is busy and cannot receive additional commands until the current is processed. In this state, the Led blinks 20 times in a second.
+
+![Processing](https://user-images.githubusercontent.com/55573252/162009007-df45111e-2473-4a92-97c5-15c3cd19babd.gif)
+
+## Driver
+
+Pico OpenPGP uses the `openpgp` driver provided by [OpenSC](https://github.com/OpenSC/OpenSC/ "OpenSC"). This driver utilizes the standardized PKCS#11 interface to communicate with the user and it can be used with many engines that accept PKCS#11 interface, such as OpenSSL, P11 library or pkcs11-tool. 
+
+It also accepts the use of GnuPG programs (`gpg` and `gpg2`) to manipulate the card. For instance, it can be used with the `gpg --edit-card --expert` interface to change the cryptographic keys, generate new keypairs or simply set the cardholder name.
+
+Pico OpenPGP relies on PKCS#15 structure to store and manipulate the internal files (PINs, private keys, certificates, etc.) and directories. Therefore, it accepts the commands from `pkcs15-tool`. For instance, `pkcs15-tool -D` will list all elements stored in the Pico OpenPGP.
+
+The way to communicate is exactly the same as with other cards, such as OpenPGP or similar.
+
+### Important
+OpenSC relies on PCSC driver, which reads a list (`Info.plist`) that contains a pair of VID/PID of supported readers. In order to be detectable, you must patch the UF2 binary (if you just downloaded from the [Release section](https://github.com/polhenarejos/pico-openpgp/releases "Release section")) or configure the project with the proper VID/PID with `USB_VID` and `USB_PID` parameters in `CMake` (see [Build section](#build "Build section")). Note that you cannot distribute the patched/compiled binary if you do not own the VID/PID or have an explicit authorization.
+
+## Credits
+Pico OpenPGP uses the following libraries or portion of code:
+- mbedTLS for cryptographic operations.
+- gnuk for low level CCID procedures support.
+- TinyUSB for low level USB procedures.
+

VERSION

@@ -0,0 +1 @@
+Version=1.4

build_pico_openpgp.sh

@@ -0,0 +1,21 @@
+#!/bin/bash
+
+VERSION_MAJOR="1"
+VERSION_MINOR="4"
+
+rm -rf release/*
+cd build_release
+
+for board in adafruit_feather_rp2040 adafruit_itsybitsy_rp2040 adafruit_qtpy_rp2040 adafruit_trinkey_qt2040 arduino_nano_rp2040_connect melopero_shake_rp2040 pimoroni_interstate75 pimoroni_keybow2040 pimoroni_pga2040 pimoroni_picolipo_4mb pimoroni_picolipo_16mb pimoroni_picosystem pimoroni_plasma2040 pimoroni_tiny2040 pybstick26_rp2040 sparkfun_micromod sparkfun_promicro sparkfun_thingplus vgaboard waveshare_rp2040_lcd_0.96 waveshare_rp2040_plus_4mb waveshare_rp2040_plus_16mb waveshare_rp2040_zero
+do
+    rm -rf *
+    PICO_SDK_PATH=~/Devel/pico/pico-sdk cmake .. -DPICO_BOARD=$board 
+    make -kj20
+    mv pico_openpgp.uf2 ../release/pico_openpgp_$board-$VERSION_MAJOR.$VERSION_MINOR.uf2
+    
+done
+
+rm -rf *
+PICO_SDK_PATH=~/Devel/pico/pico-sdk cmake ..
+make -kj20
+mv pico_openpgp.uf2 ../release/pico_openpgp_pico_generic-$VERSION_MAJOR.$VERSION_MINOR.uf2

patch_vidpid.sh

@@ -0,0 +1,94 @@
+#!/bin/bash
+
+# 
+# This file is part of the Pico OpenPGP distribution (https://github.com/polhenarejos/pico-openpgp).
+# Copyright (c) 2022 Pol Henarejos.
+# 
+# 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.
+#
+# 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 <http://www.gnu.org/licenses/>.
+#
+
+VERSION_MAJOR="1" #Version of Pico CCID Core
+VERSION_MINOR="1"
+
+echo "----------------------------"
+echo "VID/PID patcher for Pico OpenPGP"
+echo "----------------------------"
+echo ""
+
+if [ "$#" -le 0 ]; then
+    echo "Usage: $0 VID:PID [input_uf2_file] [output_uf2_file]"
+    exit 1
+fi
+
+IFS=':' read -r -a ARR <<< "$1"
+
+if [ ${#ARR[@]} -ne 2 ]; then
+    echo "ERROR: Specify vendor and product ids as VID:PID (e.g., $0 CAFE:1234)"
+    exit 1
+fi
+
+VID=${ARR[0]}
+PID=${ARR[1]}
+
+if [ ${#VID} -ne 4 ]; then
+    echo "ERROR: VID length must be 4 hexadecimal characters"
+    exit 1
+fi
+
+if [ ${#PID} -ne 4 ]; then
+    echo "ERROR: PID length must be 4 hexadecimal characters"
+    exit 1
+fi
+
+if ! [[ $VID =~ ^[0-9A-Fa-f]{1,}$ ]] ; then
+    echo "ERROR: VID must contain hexadecimal characters"
+    exit 1
+fi
+
+if ! [[ $PID =~ ^[0-9A-Fa-f]{1,}$ ]] ; then
+    echo "ERROR: PID must contain hexadecimal characters"
+    exit 1
+fi
+
+UF2_FILE_IF="pico_openpgp.uf2"
+UF2_FILE_OF="$UF2_FILE_IF"
+
+if [ "$#" -ge 2 ]; then
+    UF2_FILE_IF="$2"
+    UF2_FILE_OF="$UF2_FILE_IF"
+fi
+
+if [ "$#" -ge 3 ]; then
+    UF2_FILE_OF="$3"
+fi
+
+
+echo -n "Patching ${UF2_FILE_IF}... "
+
+if [[ ! -f "$UF2_FILE_IF" ]]; then
+    echo "ERROR: UF2 file ${UF2_FILE_IF} does not exist"
+    exit 1
+fi
+
+if [ "$UF2_FILE_IF" != "$UF2_FILE_OF" ]; then
+    cp -R $UF2_FILE_IF $UF2_FILE_OF
+fi
+
+LITTLE_VID="\x${VID:2:2}\x${VID:0:2}"
+LITTLE_PID="\x${PID:2:2}\x${PID:0:2}"
+
+perl -pi -e "s/\xff\xfe\xfd\xfc\x$VERSION_MINOR\x$VERSION_MAJOR\x01\x02\x03\x01/$LITTLE_VID$LITTLE_PID\x$VERSION_MINOR\x$VERSION_MAJOR\x01\x02\x03\x01/" $UF2_FILE_OF
+
+echo "Done!"
+echo ""
+echo "Patched file was saved in ${UF2_FILE_OF}"

src/openpgp/files.c

@@ -54,14 +54,14 @@ uint8_t historical_bytes[] = {
 
 uint8_t extended_capabilities[] = {
   10, 0,
-  0x74,				/*
+  0x77,				/*
 				 * No Secure Messaging supported
 				 * GET CHALLENGE supported
 				 * Key import supported
 				 * PW status byte can be put
 				 * No private_use_DO
 				 * Algorithm attrs are changable
-				 * No DEC with AES
+				 * ENC/DEC with AES
 				 * KDF-DO available
 				 */
   0,		  /* Secure Messaging Algorithm: N/A (TDES=0, AES=1) */
@@ -126,18 +126,18 @@ file_t file_entries[] = {
     /* 39 */ { .fid = EF_PW1, .parent = 0, .name = NULL, .type = FILE_TYPE_INTERNAL_EF | FILE_DATA_FLASH, .data = NULL, .ef_structure = FILE_EF_TRANSPARENT, .acl = ACL_WP },
     /* 40 */ { .fid = EF_RC, .parent = 0, .name = NULL, .type = FILE_TYPE_INTERNAL_EF | FILE_DATA_FLASH, .data = NULL, .ef_structure = FILE_EF_TRANSPARENT, .acl = ACL_WP },
     /* 41 */ { .fid = EF_PW3, .parent = 0, .name = NULL, .type = FILE_TYPE_INTERNAL_EF | FILE_DATA_FLASH, .data = NULL, .ef_structure = FILE_EF_TRANSPARENT, .acl = ACL_WP },
-    /* 42 */ { .fid = EF_PW1_RETRIES, .parent = 0, .name = NULL, .type = FILE_TYPE_INTERNAL_EF | FILE_DATA_FLASH, .data = NULL, .ef_structure = FILE_EF_TRANSPARENT, .acl = ACL_WP },
-    /* 43 */ { .fid = EF_RC_RETRIES, .parent = 0, .name = NULL, .type = FILE_TYPE_INTERNAL_EF | FILE_DATA_FLASH, .data = NULL, .ef_structure = FILE_EF_TRANSPARENT, .acl = ACL_WP },
-    /* 44 */ { .fid = EF_PW3_RETRIES, .parent = 0, .name = NULL, .type = FILE_TYPE_INTERNAL_EF | FILE_DATA_FLASH, .data = NULL, .ef_structure = FILE_EF_TRANSPARENT, .acl = ACL_WP },
-    /* 45 */ { .fid = EF_ALGO_PRIV1, .parent = 0, .name = NULL, .type = FILE_TYPE_INTERNAL_EF | FILE_DATA_FLASH, .data = NULL, .ef_structure = FILE_EF_TRANSPARENT, .acl = ACL_R_WP },
-    /* 46 */ { .fid = EF_ALGO_PRIV2, .parent = 0, .name = NULL, .type = FILE_TYPE_INTERNAL_EF | FILE_DATA_FLASH, .data = NULL, .ef_structure = FILE_EF_TRANSPARENT, .acl = ACL_R_WP },
-    /* 47 */ { .fid = EF_ALGO_PRIV3, .parent = 0, .name = NULL, .type = FILE_TYPE_INTERNAL_EF | FILE_DATA_FLASH, .data = NULL, .ef_structure = FILE_EF_TRANSPARENT, .acl = ACL_R_WP },
-    /* 48 */ { .fid = EF_PK_SIG, .parent = 0, .name = NULL, .type = FILE_TYPE_INTERNAL_EF | FILE_DATA_FLASH, .data = NULL, .ef_structure = FILE_EF_TRANSPARENT, .acl = ACL_WP },
-    /* 49 */ { .fid = EF_PK_DEC, .parent = 0, .name = NULL, .type = FILE_TYPE_INTERNAL_EF | FILE_DATA_FLASH, .data = NULL, .ef_structure = FILE_EF_TRANSPARENT, .acl = ACL_WP },
-    /* 50 */ { .fid = EF_PK_AUT, .parent = 0, .name = NULL, .type = FILE_TYPE_INTERNAL_EF | FILE_DATA_FLASH, .data = NULL, .ef_structure = FILE_EF_TRANSPARENT, .acl = ACL_WP },
-    /* 51 */ { .fid = EF_PB_SIG, .parent = 0, .name = NULL, .type = FILE_TYPE_INTERNAL_EF | FILE_DATA_FLASH, .data = NULL, .ef_structure = FILE_EF_TRANSPARENT, .acl = ACL_WP },
-    /* 52 */ { .fid = EF_PB_DEC, .parent = 0, .name = NULL, .type = FILE_TYPE_INTERNAL_EF | FILE_DATA_FLASH, .data = NULL, .ef_structure = FILE_EF_TRANSPARENT, .acl = ACL_WP },
-    /* 53 */ { .fid = EF_PB_AUT, .parent = 0, .name = NULL, .type = FILE_TYPE_INTERNAL_EF | FILE_DATA_FLASH, .data = NULL, .ef_structure = FILE_EF_TRANSPARENT, .acl = ACL_WP },
+    /* 42 */ { .fid = EF_ALGO_PRIV1, .parent = 0, .name = NULL, .type = FILE_TYPE_INTERNAL_EF | FILE_DATA_FLASH, .data = NULL, .ef_structure = FILE_EF_TRANSPARENT, .acl = ACL_R_WP },
+    /* 43 */ { .fid = EF_ALGO_PRIV2, .parent = 0, .name = NULL, .type = FILE_TYPE_INTERNAL_EF | FILE_DATA_FLASH, .data = NULL, .ef_structure = FILE_EF_TRANSPARENT, .acl = ACL_R_WP },
+    /* 44 */ { .fid = EF_ALGO_PRIV3, .parent = 0, .name = NULL, .type = FILE_TYPE_INTERNAL_EF | FILE_DATA_FLASH, .data = NULL, .ef_structure = FILE_EF_TRANSPARENT, .acl = ACL_R_WP },
+    /* 45 */ { .fid = EF_PK_SIG, .parent = 0, .name = NULL, .type = FILE_TYPE_INTERNAL_EF | FILE_DATA_FLASH, .data = NULL, .ef_structure = FILE_EF_TRANSPARENT, .acl = ACL_WP },
+    /* 46 */ { .fid = EF_PK_DEC, .parent = 0, .name = NULL, .type = FILE_TYPE_INTERNAL_EF | FILE_DATA_FLASH, .data = NULL, .ef_structure = FILE_EF_TRANSPARENT, .acl = ACL_WP },
+    /* 47 */ { .fid = EF_PK_AUT, .parent = 0, .name = NULL, .type = FILE_TYPE_INTERNAL_EF | FILE_DATA_FLASH, .data = NULL, .ef_structure = FILE_EF_TRANSPARENT, .acl = ACL_WP },
+    /* 48 */ { .fid = EF_PB_SIG, .parent = 0, .name = NULL, .type = FILE_TYPE_INTERNAL_EF | FILE_DATA_FLASH, .data = NULL, .ef_structure = FILE_EF_TRANSPARENT, .acl = ACL_R_WP },
+    /* 49 */ { .fid = EF_PB_DEC, .parent = 0, .name = NULL, .type = FILE_TYPE_INTERNAL_EF | FILE_DATA_FLASH, .data = NULL, .ef_structure = FILE_EF_TRANSPARENT, .acl = ACL_R_WP },
+    /* 50 */ { .fid = EF_PB_AUT, .parent = 0, .name = NULL, .type = FILE_TYPE_INTERNAL_EF | FILE_DATA_FLASH, .data = NULL, .ef_structure = FILE_EF_TRANSPARENT, .acl = ACL_R_WP },
+    /* 51 */ { .fid = EF_PW_PRIV, .parent = 0, .name = NULL, .type = FILE_TYPE_INTERNAL_EF | FILE_DATA_FLASH, .data = NULL, .ef_structure = FILE_EF_TRANSPARENT, .acl = ACL_R_WP },
+    /* 52 */ { .fid = EF_DEK, .parent = 0, .name = NULL, .type = FILE_TYPE_INTERNAL_EF | FILE_DATA_FLASH, .data = NULL, .ef_structure = FILE_EF_TRANSPARENT, .acl = ACL_NONE },
+    /* 53 */ { .fid = EF_KDF, .parent = 0, .name = NULL, .type = FILE_TYPE_WORKING_EF | FILE_DATA_FLASH, .data = NULL, .ef_structure = FILE_EF_TRANSPARENT, .acl = ACL_R_WP },
     
     /* 54 */ { .fid = 0x0000, .parent = 0, .name = openpgp_aid, .type = FILE_TYPE_WORKING_EF, .data = NULL, .ef_structure = FILE_EF_TRANSPARENT, .acl = ACL_RO },
     /* 55 */ { .fid = 0x0000, .parent = 0xff, .name = NULL, .type = FILE_TYPE_UNKNOWN, .data = NULL, .ef_structure = 0, .acl = ACL_NONE } //end

src/openpgp/files.h

@@ -24,18 +24,17 @@
 #define EF_PW1          0x1081
 #define EF_RC           0x1082
 #define EF_PW3          0x1083
-#define EF_PW1_RETRIES  0x1084
-#define EF_RC_RETRIES   0x1085
-#define EF_PW3_RETRIES  0x1086
 #define EF_ALGO_PRIV1   0x10c1
 #define EF_ALGO_PRIV2   0x10c2
 #define EF_ALGO_PRIV3   0x10c3
+#define EF_PW_PRIV      0x10c4
 #define EF_PK_SIG       0x10d1
 #define EF_PK_DEC       0x10d2
 #define EF_PK_AUT       0x10d3
 #define EF_PB_SIG       0x10d4
 #define EF_PB_DEC       0x10d5
 #define EF_PB_AUT       0x10d6
+#define EF_DEK          0x1099
 
 #define EF_EXT_HEADER   0x004d //C
 #define EF_FULL_AID     0x004f //S
@@ -68,6 +67,7 @@
 #define EF_UIF_DEC      0x00d7 //S
 #define EF_UIF_AUT      0x00d8 //S
 #define EF_KEY_INFO     0x00de //S
+#define EF_KDF          0x00f9 //C
 #define EF_ALGO_INFO    0x00fa //C
 #define EF_LANG_PREF    0x5f2d //S
 #define EF_SEX          0x5f35 //S