Add SSL_get0_verified_chain() to return verified chain of peer

Reviewed-by: Viktor Dukhovni <viktor@openssl.org>

3 files changed, 21 insertions, 2 deletions

diff --git a/ssl/ssl_cert.c b/ssl/ssl_cert.c
index 2aaf99c..68c8924 100644
--- a/ssl/ssl_cert.c
+++ b/ssl/ssl_cert.c
@@ -541,6 +541,15 @@ int ssl_verify_cert_chain(SSL *s, STACK_OF(X509) *sk)
     }
 
     s->verify_result = ctx.error;
+    sk_X509_pop_free(s->verified_chain, X509_free);
+    s->verified_chain = NULL;
+    if (X509_STORE_CTX_get_chain(&ctx) != NULL) {
+        s->verified_chain = X509_STORE_CTX_get1_chain(&ctx);
+        if (s->verified_chain == NULL) {
+            SSLerr(SSL_F_SSL_VERIFY_CERT_CHAIN, ERR_R_MALLOC_FAILURE);
+            i = 0;
+        }
+    }
 
     /* Move peername from the store context params to the SSL handle's */
     X509_VERIFY_PARAM_move_peername(s->param, param);
diff --git a/ssl/ssl_lib.c b/ssl/ssl_lib.c
index 1154b71..197a37c 100644
--- a/ssl/ssl_lib.c
+++ b/ssl/ssl_lib.c
@@ -715,6 +715,7 @@ SSL *SSL_new(SSL_CTX *ctx)
         s->alpn_client_proto_list_len = s->ctx->alpn_client_proto_list_len;
     }
 
+    s->verified_chain = NULL;
     s->verify_result = X509_V_OK;
 
     s->default_passwd_callback = ctx->default_passwd_callback;
@@ -1052,6 +1053,8 @@ void SSL_free(SSL *s)
 
     sk_X509_NAME_pop_free(s->client_CA, X509_NAME_free);
 
+    sk_X509_pop_free(s->verified_chain, X509_free);
+
     if (s->method != NULL)
         s->method->ssl_free(s);
 
@@ -3822,4 +3825,9 @@ unsigned long SSL_clear_options(SSL *s, unsigned long op)
     return s->options &= ~op;
 }
 
+STACK_OF(X509) *SSL_get0_verified_chain(const SSL *s)
+{
+    return s->verified_chain;
+}
+
 IMPLEMENT_OBJ_BSEARCH_GLOBAL_CMP_FN(SSL_CIPHER, SSL_CIPHER, ssl_cipher_id);
diff --git a/ssl/ssl_locl.h b/ssl/ssl_locl.h
index 9a30598..b505309 100644
--- a/ssl/ssl_locl.h
+++ b/ssl/ssl_locl.h
@@ -614,7 +614,7 @@ struct ssl_session_st {
     /* This is the cert and type for the other end. */
     X509 *peer;
     int peer_type;
-    /* Certificate chain of peer */
+    /* Certificate chain peer sent */
     STACK_OF(X509) *peer_chain;
     /*
      * when app_verify_callback accepts a session where the peer's
@@ -1058,8 +1058,10 @@ struct ssl_st {
                                          unsigned int max_psk_len);
 #  endif
     SSL_CTX *ctx;
-    /* extra application data */
+    /* Verified chain of peer */
+    STACK_OF(X509) *verified_chain;
     long verify_result;
+    /* extra application data */
     CRYPTO_EX_DATA ex_data;
     /* for server side, keep the list of CA_dn we can use */
     STACK_OF(X509_NAME) *client_CA;