vtls: compare and clone ssl configs properly

Compare these settings in Curl_ssl_config_matches():
- verifystatus (CURLOPT_SSL_VERIFYSTATUS)
- random_file (CURLOPT_RANDOM_FILE)
- egdsocket (CURLOPT_EGDSOCKET)

Also copy the setting "verifystatus" in Curl_clone_primary_ssl_config(),
and copy the setting "sessionid" unconditionally.

This means that reusing connections that are secured with a client
certificate is now possible, and the statement "TLS session resumption
is disabled when a client certificate is used" in the old advisory at
https://curl.haxx.se/docs/adv_20170419.html is obsolete.

Reviewed-by: Daniel Stenberg

Closes #1917

2 files changed, 16 insertions, 13 deletions

diff --git a/lib/urldata.h b/lib/urldata.h
index 5e5d98762..66e4596fd 100644
--- a/lib/urldata.h
+++ b/lib/urldata.h
@@ -210,13 +210,13 @@ struct ssl_primary_config {
   bool verifypeer;       /* set TRUE if this is desired */
   bool verifyhost;       /* set TRUE if CN/SAN must match hostname */
   bool verifystatus;     /* set TRUE if certificate status must be checked */
+  bool sessionid;        /* cache session IDs or not */
   char *CApath;          /* certificate dir (doesn't work on windows) */
   char *CAfile;          /* certificate to verify peer against */
   char *clientcert;
   char *random_file;     /* path to file containing "random" data */
   char *egdsocket;       /* path to file containing the EGD daemon socket */
   char *cipher_list;     /* list of ciphers to use */
-  bool sessionid;        /* cache session IDs or not */
 };
 
 struct ssl_config_data {
diff --git a/lib/vtls/vtls.c b/lib/vtls/vtls.c
index 56eb7ebf1..bb8fda419 100644
--- a/lib/vtls/vtls.c
+++ b/lib/vtls/vtls.c
@@ -90,9 +90,12 @@ Curl_ssl_config_matches(struct ssl_primary_config* data,
      (data->version_max == needle->version_max) &&
      (data->verifypeer == needle->verifypeer) &&
      (data->verifyhost == needle->verifyhost) &&
+     (data->verifystatus == needle->verifystatus) &&
      Curl_safe_strcasecompare(data->CApath, needle->CApath) &&
      Curl_safe_strcasecompare(data->CAfile, needle->CAfile) &&
      Curl_safe_strcasecompare(data->clientcert, needle->clientcert) &&
+     Curl_safe_strcasecompare(data->random_file, needle->random_file) &&
+     Curl_safe_strcasecompare(data->egdsocket, needle->egdsocket) &&
      Curl_safe_strcasecompare(data->cipher_list, needle->cipher_list))
     return TRUE;
 
@@ -103,31 +106,31 @@ bool
 Curl_clone_primary_ssl_config(struct ssl_primary_config *source,
                               struct ssl_primary_config *dest)
 {
-  dest->verifyhost = source->verifyhost;
-  dest->verifypeer = source->verifypeer;
   dest->version = source->version;
   dest->version_max = source->version_max;
+  dest->verifypeer = source->verifypeer;
+  dest->verifyhost = source->verifyhost;
+  dest->verifystatus = source->verifystatus;
+  dest->sessionid = source->sessionid;
 
-  CLONE_STRING(CAfile);
   CLONE_STRING(CApath);
-  CLONE_STRING(cipher_list);
-  CLONE_STRING(egdsocket);
-  CLONE_STRING(random_file);
+  CLONE_STRING(CAfile);
   CLONE_STRING(clientcert);
+  CLONE_STRING(random_file);
+  CLONE_STRING(egdsocket);
+  CLONE_STRING(cipher_list);
 
-  /* Disable dest sessionid cache if a client cert is used, CVE-2016-5419. */
-  dest->sessionid = (dest->clientcert ? false : source->sessionid);
   return TRUE;
 }
 
 void Curl_free_primary_ssl_config(struct ssl_primary_config* sslc)
 {
-  Curl_safefree(sslc->CAfile);
   Curl_safefree(sslc->CApath);
-  Curl_safefree(sslc->cipher_list);
-  Curl_safefree(sslc->egdsocket);
-  Curl_safefree(sslc->random_file);
+  Curl_safefree(sslc->CAfile);
   Curl_safefree(sslc->clientcert);
+  Curl_safefree(sslc->random_file);
+  Curl_safefree(sslc->egdsocket);
+  Curl_safefree(sslc->cipher_list);
 }
 
 #ifdef USE_SSL