Explicitly fetch ciphers and digests in libssl

We modify libssl to use explicitly fetched ciphers, digests and other
algorithms as required based on the configured library context and
property query string for the SSL_CTX that is being used.

Reviewed-by: Paul Dale <paul.dale@oracle.com>
(Merged from https://github.com/openssl/openssl/pull/10854)

1 files changed, 14 insertions, 11 deletions

diff --git a/ssl/t1_lib.c b/ssl/t1_lib.c
index fa2d6e0154..103a8f18bb 100644
--- a/ssl/t1_lib.c
+++ b/ssl/t1_lib.c
@@ -893,7 +893,7 @@ static const SIGALG_LOOKUP *tls1_lookup_sigalg(uint16_t sigalg)
     return NULL;
 }
 /* Lookup hash: return 0 if invalid or not enabled */
-int tls1_lookup_md(const SIGALG_LOOKUP *lu, const EVP_MD **pmd)
+int tls1_lookup_md(SSL_CTX *ctx, const SIGALG_LOOKUP *lu, const EVP_MD **pmd)
 {
     const EVP_MD *md;
     if (lu == NULL)
@@ -902,7 +902,7 @@ int tls1_lookup_md(const SIGALG_LOOKUP *lu, const EVP_MD **pmd)
     if (lu->hash == NID_undef) {
         md = NULL;
     } else {
-        md = ssl_md(lu->hash_idx);
+        md = ssl_md(ctx, lu->hash_idx);
         if (md == NULL)
             return 0;
     }
@@ -919,13 +919,14 @@ int tls1_lookup_md(const SIGALG_LOOKUP *lu, const EVP_MD **pmd)
  * with a 128 byte (1024 bit) key.
  */
 #define RSA_PSS_MINIMUM_KEY_SIZE(md) (2 * EVP_MD_size(md) + 2)
-static int rsa_pss_check_min_key_size(const RSA *rsa, const SIGALG_LOOKUP *lu)
+static int rsa_pss_check_min_key_size(SSL_CTX *ctx, const RSA *rsa,
+                                      const SIGALG_LOOKUP *lu)
 {
     const EVP_MD *md;
 
     if (rsa == NULL)
         return 0;
-    if (!tls1_lookup_md(lu, &md) || md == NULL)
+    if (!tls1_lookup_md(ctx, lu, &md) || md == NULL)
         return 0;
     if (RSA_size(rsa) < RSA_PSS_MINIMUM_KEY_SIZE(md))
         return 0;
@@ -978,7 +979,7 @@ static const SIGALG_LOOKUP *tls1_get_legacy_sigalg(const SSL *s, int idx)
     if (SSL_USE_SIGALGS(s) || idx != SSL_PKEY_RSA) {
         const SIGALG_LOOKUP *lu = tls1_lookup_sigalg(tls_default_sigalg[idx]);
 
-        if (!tls1_lookup_md(lu, NULL))
+        if (!tls1_lookup_md(s->ctx, lu, NULL))
             return NULL;
         if (!tls12_sigalg_allowed(s, SSL_SECOP_SIGALG_SUPPORTED, lu))
             return NULL;
@@ -1183,7 +1184,7 @@ int tls12_check_peer_sigalg(SSL *s, uint16_t sig, EVP_PKEY *pkey)
                  SSL_R_WRONG_SIGNATURE_TYPE);
         return 0;
     }
-    if (!tls1_lookup_md(lu, &md)) {
+    if (!tls1_lookup_md(s->ctx, lu, &md)) {
         SSLfatal(s, SSL_AD_HANDSHAKE_FAILURE, SSL_F_TLS12_CHECK_PEER_SIGALG,
                  SSL_R_UNKNOWN_DIGEST);
         return 0;
@@ -1670,7 +1671,7 @@ static int tls12_sigalg_allowed(const SSL *s, int op, const SIGALG_LOOKUP *lu)
     int secbits;
 
     /* See if sigalgs is recognised and if hash is enabled */
-    if (!tls1_lookup_md(lu, NULL))
+    if (!tls1_lookup_md(s->ctx, lu, NULL))
         return 0;
     /* DSA is not allowed in TLS 1.3 */
     if (SSL_IS_TLS13(s) && lu->sig == EVP_PKEY_DSA)
@@ -1728,7 +1729,7 @@ static int tls12_sigalg_allowed(const SSL *s, int op, const SIGALG_LOOKUP *lu)
     if (lu->hash == NID_undef)
         return 1;
     /* Security bits: half digest bits */
-    secbits = EVP_MD_size(ssl_md(lu->hash_idx)) * 4;
+    secbits = EVP_MD_size(ssl_md(s->ctx, lu->hash_idx)) * 4;
     /* Finally see if security callback allows it */
     sigalgstr[0] = (lu->sigalg >> 8) & 0xff;
     sigalgstr[1] = lu->sigalg & 0xff;
@@ -2777,7 +2778,7 @@ static const SIGALG_LOOKUP *find_sig_alg(SSL *s, X509 *x, EVP_PKEY *pkey)
             || lu->sig == EVP_PKEY_RSA)
             continue;
         /* Check that we have a cert, and signature_algorithms_cert */
-        if (!tls1_lookup_md(lu, NULL))
+        if (!tls1_lookup_md(s->ctx, lu, NULL))
             continue;
         if ((pkey == NULL && !has_usable_cert(s, lu, -1))
                 || (pkey != NULL && !is_cert_usable(s, lu, x, pkey)))
@@ -2799,7 +2800,7 @@ static const SIGALG_LOOKUP *find_sig_alg(SSL *s, X509 *x, EVP_PKEY *pkey)
 #endif
         } else if (lu->sig == EVP_PKEY_RSA_PSS) {
             /* validate that key is large enough for the signature algorithm */
-            if (!rsa_pss_check_min_key_size(EVP_PKEY_get0(tmppkey), lu))
+            if (!rsa_pss_check_min_key_size(s->ctx, EVP_PKEY_get0(tmppkey), lu))
                 continue;
         }
         break;
@@ -2885,7 +2886,9 @@ int tls_choose_sigalg(SSL *s, int fatalerrs)
                         /* validate that key is large enough for the signature algorithm */
                         EVP_PKEY *pkey = s->cert->pkeys[sig_idx].privatekey;
 
-                        if (!rsa_pss_check_min_key_size(EVP_PKEY_get0(pkey), lu))
+                        if (!rsa_pss_check_min_key_size(s->ctx,
+                                                        EVP_PKEY_get0(pkey),
+                                                        lu))
                             continue;
                     }
 #ifndef OPENSSL_NO_EC