Clemens Lang 6c73ca4a2f signature: Clamp PSS salt len to MD len ... FIPS 186-4 section 5 "The RSA Digital Signature Algorithm", subsection 5.5 "PKCS #1" says: "For RSASSA-PSS […] the length (in bytes) of the salt (sLen) shall satisfy 0 <= sLen <= hLen, where hLen is the length of the hash function output block (in bytes)." Introduce a new option RSA_PSS_SALTLEN_AUTO_DIGEST_MAX and make it the default. The new value will behave like RSA_PSS_SALTLEN_AUTO, but will not use more than the digest length when signing, so that FIPS 186-4 is not violated. This value has two advantages when compared with RSA_PSS_SALTLEN_DIGEST: (1) It will continue to do auto-detection when verifying signatures for maximum compatibility, where RSA_PSS_SALTLEN_DIGEST would fail for other digest sizes. (2) It will work for combinations where the maximum salt length is smaller than the digest size, which typically happens with large digest sizes (e.g., SHA-512) and small RSA keys. J.-S. Coron shows in "Optimal Security Proofs for PSS and Other Signature Schemes. Advances in Cryptology – Eurocrypt 2002, volume 2332 of Lecture Notes in Computer Science, pp. 272 – 287. Springer Verlag, 2002." that longer salts than the output size of modern hash functions do not increase security: "For example,for an application in which at most one billion signatures will be generated, k0 = 30 bits of random salt are actually sufficient to guarantee the same level of security as RSA, and taking a larger salt does not increase the security level." Signed-off-by: Clemens Lang <cllang@redhat.com> Reviewed-by: Dmitry Belyavskiy <beldmit@gmail.com> Reviewed-by: Tomas Mraz <tomas@openssl.org> (Merged from https://github.com/openssl/openssl/pull/19724)		2022-12-08 11:02:52 +01:00
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ca.cnf	test/smime-certs/ca.cnf: clean up comments, simplify settings using SKID and AKID defaults	2022-11-18 15:10:02 +01:00
csrsa1.pem
mksmime-certs.sh	signature: Clamp PSS salt len to MD len	2022-12-08 11:02:52 +01:00
smdh.pem
smdsa1.pem
smdsa2.pem
smdsa3.pem
smdsap.pem
smec1.pem
smec2.pem
smec3.pem
smroot.pem
smrsa1.pem
smrsa2.pem
smrsa3.pem
smrsa1024.pem	signature: Clamp PSS salt len to MD len	2022-12-08 11:02:52 +01:00