Run ./GenCertificates.sh, answering the prompt to produce your own certificate.
From Teensy U2F line 292
Instructions to generate attestation certificate using open ssl OpenSSL wiki Guy Rutenberg P-256 (also secp256r1) EC key pair is W = dG (Note secp256k1 is Koblitz curve - not P256) d = private key is it 256 bits (32 bytes) G = generator point - it is part of the curve definition W = public key point - it is a (256, 256) bits - 64 bytes
- Generate a key pair - the private key will be saved in PKCS8 format in ecprivkey.pem
openssl ecparam -name prime256v1 -genkey -noout -out ecprivkey.pem
- Dump out the private key in hex format - it will be a 32 byte key
openssl asn1parse -in ecprivkey.pem
- Compute the public key from the private key and the curve
openssl ec -in ecprivkey.pem -pubout -out ecpubkey.pem
- Dump out the public key in hex format - it will be 66 byte - the first two bytes are 00 04,
openssl ec -in ecprivkey.pem -pubout -text
after that is the point W - 32 byte + 32 byte
- Generate a self signed certificate
openssl req -new -x509 -key ecprivkey.pem -out certificate.pem -days 3650
For the Certificate name give a unique certificate name.
- Display the certificate
openssl x509 -in certificate.pem -text -noout
- Convert PEM certificate to DER
openssl x509 -outform der -in certificate.pem -out certificate.der
- Generate a usable c-array for source code
xxd --include certificate.der | sed -e '0,/{/d;/};/,$d'
Copy output into appropriate array in 'Certificates.cpp', overwriting existing values
- Find the public key
openssl ec -in ecprivkey.pem -pubout -text -noout 2>/dev/null | sed -e '0,/priv:/d;/pub:/,$d' -e 's/\s//g;s/:/, /g' -e 's/^/\t/g;s/\s\+$//g' -e 's/\(\s\)/\10x/g'
- Find the private key
openssl ec -in ecprivkey.pem -pubout -text -noout 2>/dev/null | sed -e '0,/pub:/d;/ASN1/,$d' | sed -e 's/\s//g;s/:/, /g' -e 's/^/\t/g;s/\s\+$//g' -e 's/\(\s\)/\10x/g'
Copy the arrays into the correct arrays in Certificates.cpp.
If any arrays have different lengths than shown in Certificates.hpp, update these too.