Let SSL_copy_session_id() return an int for error checking.

Accordingly, add some error checking to SSL_copy_session_id(),
BIO_ssl_copy_session_id(), and SSL_dup().
Prompted by OpenSSL commit 17dd65e6e1f

Tested in a bulk build by sthen

ok jsing

3 files changed, 31 insertions, 28 deletions

diff --git a/src/lib/libssl/bio_ssl.c b/src/lib/libssl/bio_ssl.c
index d68e011c62..93cfa0d2a4 100644
--- a/src/lib/libssl/bio_ssl.c
+++ b/src/lib/libssl/bio_ssl.c
@@ -1,4 +1,4 @@
-/* $OpenBSD: bio_ssl.c,v 1.28 2018/05/01 13:30:24 tb Exp $ */
+/* $OpenBSD: bio_ssl.c,v 1.29 2018/08/24 20:30:21 tb Exp $ */
 /* Copyright (C) 1995-1998 Eric Young (eay@cryptsoft.com)
  * All rights reserved.
  *
@@ -568,7 +568,9 @@ BIO_ssl_copy_session_id(BIO *t, BIO *f)
         if ((((BIO_SSL *)t->ptr)->ssl == NULL) ||
             (((BIO_SSL *)f->ptr)->ssl == NULL))
                 return (0);
-        SSL_copy_session_id(((BIO_SSL *)t->ptr)->ssl, ((BIO_SSL *)f->ptr)->ssl);
+        if (!SSL_copy_session_id(((BIO_SSL *)t->ptr)->ssl,
+            ((BIO_SSL *)f->ptr)->ssl))
+                return (0);
         return (1);
 }
 
diff --git a/src/lib/libssl/ssl.h b/src/lib/libssl/ssl.h
index c3b553fa2f..324691485b 100644
--- a/src/lib/libssl/ssl.h
+++ b/src/lib/libssl/ssl.h
@@ -1,4 +1,4 @@
-/* $OpenBSD: ssl.h,v 1.158 2018/05/01 13:30:24 tb Exp $ */
+/* $OpenBSD: ssl.h,v 1.159 2018/08/24 20:30:21 tb Exp $ */
 /* Copyright (C) 1995-1998 Eric Young (eay@cryptsoft.com)
  * All rights reserved.
  *
@@ -1311,7 +1311,7 @@ long	SSL_SESSION_get_time(const SSL_SESSION *s);
 long    SSL_SESSION_set_time(SSL_SESSION *s, long t);
 long    SSL_SESSION_get_timeout(const SSL_SESSION *s);
 long    SSL_SESSION_set_timeout(SSL_SESSION *s, long t);
-void    SSL_copy_session_id(SSL *to, const SSL *from);
+int     SSL_copy_session_id(SSL *to, const SSL *from);
 X509    *SSL_SESSION_get0_peer(SSL_SESSION *s);
 int     SSL_SESSION_set1_id(SSL_SESSION *s, const unsigned char *sid,
             unsigned int sid_len);
diff --git a/src/lib/libssl/ssl_lib.c b/src/lib/libssl/ssl_lib.c
index 4f1eb5bf0a..0dbc7b3707 100644
--- a/src/lib/libssl/ssl_lib.c
+++ b/src/lib/libssl/ssl_lib.c
@@ -1,4 +1,4 @@
-/* $OpenBSD: ssl_lib.c,v 1.185 2018/04/25 07:10:39 tb Exp $ */
+/* $OpenBSD: ssl_lib.c,v 1.186 2018/08/24 20:30:21 tb Exp $ */
 /* Copyright (C) 1995-1998 Eric Young (eay@cryptsoft.com)
  * All rights reserved.
  *
@@ -853,22 +853,21 @@ SSL_get_peer_cert_chain(const SSL *s)
  * Now in theory, since the calling process own 't' it should be safe to
  * modify.  We need to be able to read f without being hassled
  */
-void
+int
 SSL_copy_session_id(SSL *t, const SSL *f)
 {
         CERT    *tmp;
 
-        /* Do we need to to SSL locking? */
-        SSL_set_session(t, SSL_get_session(f));
+        /* Do we need to do SSL locking? */
+        if (!SSL_set_session(t, SSL_get_session(f)))
+                return 0;
 
-        /*
-         * What if we are setup as SSLv2 but want to talk SSLv3 or
-         * vice-versa.
-         */
+        /* What if we are set up for one protocol but want to talk another? */
         if (t->method != f->method) {
-                t->method->internal->ssl_free(t);       /* cleanup current */
-                t->method = f->method;  /* change method */
-                t->method->internal->ssl_new(t);        /* setup new */
+                t->method->internal->ssl_free(t);
+                t->method = f->method;
+                if (!t->method->internal->ssl_new(t))
+                        return 0;
         }
 
         tmp = t->cert;
@@ -878,7 +877,11 @@ SSL_copy_session_id(SSL *t, const SSL *f)
         } else
                 t->cert = NULL;
         ssl_cert_free(tmp);
-        SSL_set_session_id_context(t, f->sid_ctx, f->sid_ctx_length);
+
+        if (!SSL_set_session_id_context(t, f->sid_ctx, f->sid_ctx_length))
+                return 0;
+
+        return 1;
 }
 
 /* Fix this so it checks all the valid key/cert options */
@@ -2500,15 +2503,15 @@ SSL_dup(SSL *s)
         int i;
 
         if ((ret = SSL_new(SSL_get_SSL_CTX(s))) == NULL)
-                return (NULL);
+                goto err;
 
         ret->version = s->version;
         ret->internal->type = s->internal->type;
         ret->method = s->method;
 
         if (s->session != NULL) {
-                /* This copies session-id, SSL_METHOD, sid_ctx, and 'cert' */
-                SSL_copy_session_id(ret, s);
+                if (!SSL_copy_session_id(ret, s))
+                        goto err;
         } else {
                 /*
                  * No session has been established yet, so we have to expect
@@ -2528,8 +2531,9 @@ SSL_dup(SSL *s)
                                 goto err;
                 }
 
-                SSL_set_session_id_context(ret,
-                s->sid_ctx, s->sid_ctx_length);
+                if (!SSL_set_session_id_context(ret, s->sid_ctx,
+                    s->sid_ctx_length))
+                        goto err;
         }
 
         ret->internal->options = s->internal->options;
@@ -2612,13 +2616,10 @@ SSL_dup(SSL *s)
                 }
         }
 
-        if (0) {
-err:
-                if (ret != NULL)
-                        SSL_free(ret);
-                ret = NULL;
-        }
-        return (ret);
+        return ret;
+ err:
+        SSL_free(ret);
+        return NULL;
 }
 
 void