# Generate local (insecure) root key and certificate The version 3 (v3 and v3\_attest) extensions define the certificate format and establish the Certificate Authority (CA). This process allows you to create a local CA with specific attributes and constraints set by the v3 extensions, allowing you to issue certificates for testing and development purposes. Follow these steps to generate a local root key and certificate. 1. To create `opensslroot.cfg` file, see [Sample OpenSSL configuration](https://docs.qualcomm.com/doc/80-70018-11/topic/appendix-openssl-configuration.html#appendix-openssl-configuration). 2. To create the `v3.ext` and `v3_attest.ext` extensions, use the following: - `v3.ext`: This extension can be found at [/docs/manmaster/man5/x509v3_config.html (OpenSSL.org)](https://www.openssl.org/docs/manmaster/man5/x509v3_config.html), and include the following settings: authorityKeyIdentifier=keyid,issuer subjectKeyIdentifier=hash basicConstraints=CA:true,pathlen:0 keyUsage=keyCertSign Copy to clipboard - `v3_attest.ext`: This extension can be found at [/docs/manmaster/man5/x509v3_config.html (OpenSSL.org)](https://www.openssl.org/docs/manmaster/man5/x509v3_config.html), and include the following settings: authorityKeyIdentifier=keyid,issuer basicConstraints=CA:FALSE,pathlen:0 keyUsage=digitalSignature extendedKeyUsage=codeSigning Copy to clipboard 3. Prepare the environment, create a directory named OEM-KEYS to generate all certificates and keys at one location. - For Linux, use the following commands: cd /path/to/sectools/$ mkdir ./OEM-KEYS && cp /download/opensslroot.cfg ./OEM-KEYS && cp /download/v3.ext ./OEM-KEYS && cp /download/v3_attest.ext ./OEM-KEYS Copy to clipboard - For Windows, copy `opensslroot.cfg`, `v3.ext`, and `v3_attest.ext` to the OEM-KEYS directory. The supported algorithms include: - Rivest–Shamir–Adleman (RSA) signature algorithm - Elliptical curve digital signature algorithm (ECDSA) ## Next steps - To enhance device security by providing stronger cryptographic protection and better performance, you must generate the ECDSA root key and certificate. For more information, see [Generate ECDSA root key and certificate](https://docs.qualcomm.com/doc/80-70018-11/topic/generate-ecdsa-root-key-and-certificate.html#generate-ecdsa-root-key-and-certificate). - To allow client applications to authenticate securely and enable encrypted communication, see [Generate RSA CA key pair and certificate](https://docs.qualcomm.com/doc/80-70018-11/topic/generate-rsa-root-ca-key-pair-and-certificate.html#generate-rsa-root-ca-key-pair-and-certificate). Last Published: Apr 10, 2025 [Previous Topic QFPROM fuses](https://docs.qualcomm.com/bundle/publicresource/80-70018-11/topics/appendix-fuse-configurations.md) [Next Topic Generate ECDSA root key and certificate](https://docs.qualcomm.com/bundle/publicresource/80-70018-11/topics/generate-ecdsa-root-key-and-certificate.md)