Add support for RSASSA-PSS signatures (RFC8017) for use with module signing and other public key cryptography done by the kernel.
Note that only signature verification is supported by the kernel. Note further that this alters some of the same code as the MLDSA support, so that needs to be applied first to avoid conflicts. Signed-off-by: David Howells <[email protected]> cc: Lukas Wunner <[email protected]> cc: Ignat Korchagin <[email protected]> cc: Herbert Xu <[email protected]> cc: [email protected] cc: [email protected] --- certs/Kconfig | 6 ++++++ certs/Makefile | 1 + scripts/sign-file.c | 39 +++++++++++++++++++++++++++++++++++++-- 3 files changed, 44 insertions(+), 2 deletions(-) diff --git a/certs/Kconfig b/certs/Kconfig index 94b086684d07..beb8991ad761 100644 --- a/certs/Kconfig +++ b/certs/Kconfig @@ -27,6 +27,12 @@ config MODULE_SIG_KEY_TYPE_RSA help Use an RSA key for module signing. +config MODULE_SIG_KEY_TYPE_RSASSA_PSS + bool "RSASSA-PSS" + select CRYPTO_RSA + help + Use an RSASSA-PSS key for module signing. + config MODULE_SIG_KEY_TYPE_ECDSA bool "ECDSA" select CRYPTO_ECDSA diff --git a/certs/Makefile b/certs/Makefile index 3ee1960f9f4a..3b5a3a303f4c 100644 --- a/certs/Makefile +++ b/certs/Makefile @@ -42,6 +42,7 @@ targets += x509_certificate_list # boolean option and we unfortunately can't make it depend on !RANDCONFIG. ifeq ($(CONFIG_MODULE_SIG_KEY),certs/signing_key.pem) +keytype-$(CONFIG_MODULE_SIG_KEY_TYPE_RSASSA_PSS) := -newkey rsassa-pss keytype-$(CONFIG_MODULE_SIG_KEY_TYPE_ECDSA) := -newkey ec -pkeyopt ec_paramgen_curve:secp384r1 keytype-$(CONFIG_MODULE_SIG_KEY_TYPE_MLDSA_44) := -newkey ml-dsa-44 keytype-$(CONFIG_MODULE_SIG_KEY_TYPE_MLDSA_65) := -newkey ml-dsa-65 diff --git a/scripts/sign-file.c b/scripts/sign-file.c index b726581075f9..ca605095194e 100644 --- a/scripts/sign-file.c +++ b/scripts/sign-file.c @@ -233,6 +233,7 @@ int main(int argc, char **argv) EVP_PKEY *private_key; #ifndef USE_PKCS7 CMS_ContentInfo *cms = NULL; + CMS_SignerInfo *signer; unsigned int use_keyid = 0; #else PKCS7 *pkcs7 = NULL; @@ -329,13 +330,47 @@ int main(int argc, char **argv) !EVP_PKEY_is_a(private_key, "ML-DSA-65") && !EVP_PKEY_is_a(private_key, "ML-DSA-87")) flags |= use_signed_attrs; + if (EVP_PKEY_is_a(private_key, "RSASSA-PSS")) + flags |= CMS_KEY_PARAM; + if (EVP_PKEY_is_a(private_key, "RSASSA-PSS")) { + EVP_PKEY_CTX *pkctx; + char mdname[1024] = {}; + + pkctx = EVP_PKEY_CTX_new(private_key, NULL); + + ERR(!EVP_PKEY_sign_init(pkctx), "EVP_PKEY_sign_init"); + ERR(!EVP_PKEY_CTX_set_rsa_padding(pkctx, RSA_PKCS1_PSS_PADDING), + "EVP_PKEY_CTX_set_rsa_padding"); + ERR(!EVP_PKEY_CTX_set_rsa_mgf1_md_name(pkctx, hash_algo, NULL), + "EVP_PKEY_CTX_set_rsa_mgf1_md_name"); + + ERR(!EVP_PKEY_CTX_get_rsa_mgf1_md_name(pkctx, mdname, sizeof(mdname)), + "EVP_PKEY_CTX_get_rsa_mgf1_md_name"); + printf("RSASSA-PSS %s\n", mdname); + } /* Load the signature message from the digest buffer. */ cms = CMS_sign(NULL, NULL, NULL, NULL, flags); ERR(!cms, "CMS_sign"); - ERR(!CMS_add1_signer(cms, x509, private_key, digest_algo, flags), - "CMS_add1_signer"); + signer = CMS_add1_signer(cms, x509, private_key, digest_algo, flags); + ERR(!signer, "CMS_add1_signer"); + + if (EVP_PKEY_is_a(private_key, "RSASSA-PSS")) { + EVP_PKEY_CTX *pkctx; + char mdname[1024] = {}; + + pkctx = CMS_SignerInfo_get0_pkey_ctx(signer); + ERR(!EVP_PKEY_CTX_set_rsa_padding(pkctx, RSA_PKCS1_PSS_PADDING), + "EVP_PKEY_CTX_set_rsa_padding"); + ERR(!EVP_PKEY_CTX_set_rsa_mgf1_md_name(pkctx, hash_algo, NULL), + "EVP_PKEY_CTX_set_rsa_mgf1_md_name"); + + ERR(!EVP_PKEY_CTX_get_rsa_mgf1_md_name(pkctx, mdname, sizeof(mdname)), + "EVP_PKEY_CTX_get_rsa_mgf1_md_name"); + printf("RSASSA-PSS %s\n", mdname); + } + ERR(CMS_final(cms, bm, NULL, flags) != 1, "CMS_final");
