Update Channel ID API to use a callback.

openssl/ssl/s3_clnt.c

 /* ssl/s3_clnt.c */
 /* Copyright (C) 1995-1998 Eric Young (eay@cryptsoft.com)
  * All rights reserved.
  *
  * This package is an SSL implementation written
  * by Eric Young (eay@cryptsoft.com).
  * The implementation was written so as to conform with Netscapes SSL.
  * 
  * This library is free for commercial and non-commercial use as long as
  * the following conditions are aheared to.  The following conditions
@@ skipping 3396 matching lines @@
         unsigned char *d;
         int ret = -1, public_key_len;
         EVP_MD_CTX md_ctx;
         size_t sig_len;
         ECDSA_SIG *sig = NULL;
         unsigned char *public_key = NULL, *derp, *der_sig = NULL;
 
         if (s->state != SSL3_ST_CW_CHANNEL_ID_A)
                 return ssl3_do_write(s, SSL3_RT_HANDSHAKE);
 
-        if (s->tlsext_channel_id_private == NULL)
-            {
-                s->rwstate=SSL_CHANNEL_ID_LOOKUP;
-                return (-1);
-            }
-        s->rwstate=SSL_NOTHING;
+        if (!s->tlsext_channel_id_private && s->ctx->channel_id_cb)
+                {
+                EVP_PKEY* key = NULL;

[agl, 2013/10/22 20:00:17]

* on the right in OpenSSL.

+                s->ctx->channel_id_cb(s, &key);
+                if (key != NULL)
+                        {
+                        s->tlsext_channel_id_private = EVP_PKEY_dup(key);
+                        }
+                }
+        if (!s->tlsext_channel_id_private)
+                {
+                s->rwstate=SSL_CHANNEL_ID_LOOKUP;
+                return (-1);
+                }
+        s->rwstate=SSL_NOTHING;
 
         d = (unsigned char *)s->init_buf->data;
         *(d++)=SSL3_MT_ENCRYPTED_EXTENSIONS;
         l2n3(2 + 2 + TLSEXT_CHANNEL_ID_SIZE, d);
         s2n(TLSEXT_TYPE_channel_id, d);
         s2n(TLSEXT_CHANNEL_ID_SIZE, d);
 
         EVP_MD_CTX_init(&md_ctx);
 
         public_key_len = i2d_PublicKey(s->tlsext_channel_id_private, NULL);
@@ skipping 126 matching lines @@
                                                 SSL_get_client_CA_list(s),
                                                 px509, ppkey, NULL, NULL, NULL);
                 if (i != 0)
                         return i;
                 }
 #endif
         if (s->ctx->client_cert_cb)
                 i = s->ctx->client_cert_cb(s,px509,ppkey);
         return i;
         }