TBB: use SHA256 to generate the certificate signatures

This patch replaces SHA1 by SHA256 in the 'cert_create' tool, so
certificate signatures are generated according to the NSA Suite B
cryptographic algorithm requirements.

Documentation updated accordingly.

Change-Id: I7be79e6b2b62dac8dc78a4f4f5006e37686bccf6
This commit is contained in:
Juan Castillo 2015-02-16 10:34:28 +00:00
parent 5930eadbe5
commit ea4ec3aad5
2 changed files with 4 additions and 5 deletions

View File

@ -44,10 +44,9 @@ essential information to establish the CoT.
In the TBB CoT all certificates are self-signed. There is no need for a
Certificate Authority (CA) because the CoT is not established by verifying the
validity of a certificate's issuer but by the content of the certificate
extensions. To sign the certificates, the PKCS#1 SHA-1 with RSA Encryption
extensions. To sign the certificates, the PKCS#1 SHA-256 with RSA Encryption
signature scheme is used with a RSA key length of 2048 bits. Future version of
Trusted Firmware will replace SHA-1 usage with SHA-256 and support additional
cryptographic algorithms.
Trusted Firmware will support additional cryptographic algorithms.
The certificates are categorised as "Key" and "Content" certificates. Key
certificates are used to verify public keys which have been used to sign content
@ -218,7 +217,7 @@ corresponding certificates or images at each step in the Trusted Board Boot
sequence. The module relies on the PolarSSL library (v1.3.9) to perform the
following operations:
* Parsing X.509 certificates and verifying them using SHA-1 with RSA
* Parsing X.509 certificates and verifying them using SHA-256 with RSA
Encryption.
* Extracting public keys and hashes from the certificates.
* Generating hashes (SHA-256) of boot loader images

View File

@ -170,7 +170,7 @@ int cert_new(cert_t *cert, int days, int ca, STACK_OF(X509_EXTENSION) * sk)
}
/* Sign the certificate with the issuer key */
if (!X509_sign(x, ikey, EVP_sha1())) {
if (!X509_sign(x, ikey, EVP_sha256())) {
ERR_print_errors_fp(stdout);
return 0;
}