OpenSSL: fix tls_try_verify_hosts under resumption

[exim.git] / src / src / tls-openssl.c

diff --git a/src/src/tls-openssl.c b/src/src/tls-openssl.c
index 4b38477123b9a5bd530669072723b13226060b91..39e7fc8f4946f52245cfa86f4367324d0eeb8297 100644 (file)
--- a/src/src/tls-openssl.c
+++ b/src/src/tls-openssl.c
@@ -315,7 +315,7 @@ static SSL_CTX *server_sni = NULL;
 
 static char ssl_errstring[256];
 
-static int  ssl_session_timeout = 3600;
+static int  ssl_session_timeout = 7200;                /* Two hours */
 static BOOL client_verify_optional = FALSE;
 static BOOL server_verify_optional = FALSE;
 
@@ -526,6 +526,7 @@ if (ev)
       }
     DEBUG(D_tls) debug_printf("Event-action verify failure overridden "
       "(host in tls_try_verify_hosts)\n");
+    tlsp->verify_override = TRUE;
     }
   X509_free(tlsp->peercert);
   tlsp->peercert = old_cert;
@@ -585,6 +586,7 @@ if (!X509_NAME_oneline(X509_get_subject_name(cert), CS dn, sizeof(dn)))
   }
 dn[sizeof(dn)-1] = '\0';
 
+tlsp->verify_override = FALSE;
 if (preverify_ok == 0)
   {
   uschar * extra = verify_mode ? string_sprintf(" (during %c-verify for [%s])",
@@ -603,6 +605,7 @@ if (preverify_ok == 0)
     }
   DEBUG(D_tls) debug_printf("SSL verify failure overridden (host in "
     "tls_try_verify_hosts)\n");
+  tlsp->verify_override = TRUE;
   }
 
 else if (depth != 0)
@@ -679,8 +682,9 @@ else
          tlsp->peercert = X509_dup(cert);      /* record failing cert */
        return 0;                               /* reject */
        }
-      DEBUG(D_tls) debug_printf("SSL verify failure overridden (host in "
+      DEBUG(D_tls) debug_printf("SSL verify name failure overridden (host in "
        "tls_try_verify_hosts)\n");
+      tlsp->verify_override = TRUE;
       }
     }
 
@@ -691,7 +695,6 @@ else
 
   DEBUG(D_tls) debug_printf("SSL%s verify ok: depth=0 SN=%s\n",
     *calledp ? "" : " authenticated", dn);
-  if (!*calledp) tlsp->certificate_verified = TRUE;
   *calledp = TRUE;
   }
 
@@ -748,7 +751,7 @@ DEBUG(D_tls) debug_printf("verify_callback_client_dane: %s depth %d %s\n",
 
 if (preverify_ok == 1)
   {
-  tls_out.dane_verified = tls_out.certificate_verified = TRUE;
+  tls_out.dane_verified = TRUE;
 #ifndef DISABLE_OCSP
   if (client_static_cbinfo->u_ocsp.client.verify_store)
     {  /* client, wanting stapling  */
@@ -941,6 +944,12 @@ else
   EVP_DecryptInit_ex(ctx, key->aes_cipher, NULL, key->aes_key, iv);
 
   DEBUG(D_tls) debug_printf("ticket usable, STEK expire %ld\n", key->expire - now);
+
+  /* The ticket lifetime and renewal are the same as the STEK lifetime and
+  renewal, which is overenthusiastic.  A factor of, say, 3x longer STEK would
+  be better.  To do that we'd have to encode ticket lifetime in the name as
+  we don't yet see the restored session.  Could check posthandshake for TLS1.3
+  and trigger a new ticket then, but cannot do that for TLS1.2 */
   return key->renew < now ? 2 : 1;
   }
 }
@@ -2153,8 +2162,24 @@ if (tlsp->peercert)
     { DEBUG(D_tls) debug_printf("X509_NAME_oneline() error\n"); }
   else
     {
-    peerdn[siz-1] = '\0';
-    tlsp->peerdn = peerdn;             /*XXX a static buffer... */
+    int oldpool = store_pool;
+
+    peerdn[siz-1] = '\0';              /* paranoia */
+    store_pool = POOL_PERM;
+    tlsp->peerdn = string_copy(peerdn);
+    store_pool = oldpool;
+
+    /* We used to set CV in the cert-verify callbacks (either plain or dane)
+    but they don't get called on session-resumption.  So use the official
+    interface, which uses the resumed value.  Unfortunately this claims verified
+    when it actually failed but we're in try-verify mode, due to us wanting the
+    knowlege that it failed so needing to have the callback and forcing a
+    permissive return.  If we don't force it, the TLS startup is failed.
+    The extra bit of information is set in verify_override in the cb, stashed
+    for resumption next to the TLS session, and used here. */
+
+    if (!tlsp->verify_override)
+      tlsp->certificate_verified = SSL_get_verify_result(ssl) == X509_V_OK;
     }
 }
 
@@ -2714,6 +2739,12 @@ if (tlsp->host_resumable)
          debug_printf("decoding session: %s\n", ssl_errstring);
          }
        }
+      else if ( SSL_SESSION_get_ticket_lifetime_hint(ss) + dt->time_stamp
+              < time(NULL))
+       {
+       DEBUG(D_tls) debug_printf("session expired\n");
+       dbfn_delete(dbm_file, key);
+       }
       else if (!SSL_set_session(ssl, ss))
        {
        DEBUG(D_tls)
@@ -2727,6 +2758,7 @@ if (tlsp->host_resumable)
        {
        DEBUG(D_tls) debug_printf("good session\n");
        tlsp->resumption |= RESUME_CLIENT_SUGGESTED;
+       tlsp->verify_override = dt->verify_override;
        }
       }
     else
@@ -2762,7 +2794,8 @@ if (SSL_SESSION_is_resumable(ss))         /* 1.1.1 */
   DEBUG(D_tls) debug_printf("session is resumable\n");
   tlsp->resumption |= RESUME_SERVER_TICKET;    /* server gave us a ticket */
 
-  len = i2d_SSL_SESSION(ss, &s);       /* s gets bumped to end */
+  dt->verify_override = tlsp->verify_override;
+  (void) i2d_SSL_SESSION(ss, &s);              /* s gets bumped to end */
 
   if ((dbm_file = dbfn_open(US"tls", O_RDWR, &dbblock, FALSE, FALSE)))
     {