Custom extension revision.
authorDr. Stephen Henson <steve@openssl.org>
Sun, 10 Aug 2014 11:08:08 +0000 (12:08 +0100)
committerDr. Stephen Henson <steve@openssl.org>
Thu, 28 Aug 2014 16:06:52 +0000 (17:06 +0100)
Use the same structure for client and server custom extensions.

Add utility functions in new file t1_ext.c.
Use new utility functions to handle custom server and client extensions
and remove a lot of code duplication.
Reviewed-by: Emilia Käsper <emilia@openssl.org>
ssl/Makefile
ssl/s23_clnt.c
ssl/ssl.h
ssl/ssl_cert.c
ssl/ssl_lib.c
ssl/ssl_locl.h
ssl/t1_ext.c [new file with mode: 0644]
ssl/t1_lib.c

index 70446b9..f39b88c 100644 (file)
@@ -24,7 +24,7 @@ LIBSRC=       \
        s2_meth.c   s2_srvr.c s2_clnt.c  s2_lib.c  s2_enc.c s2_pkt.c \
        s3_meth.c   s3_srvr.c s3_clnt.c  s3_lib.c  s3_enc.c s3_pkt.c s3_both.c s3_cbc.c \
        s23_meth.c s23_srvr.c s23_clnt.c s23_lib.c          s23_pkt.c \
-       t1_meth.c   t1_srvr.c t1_clnt.c  t1_lib.c  t1_enc.c \
+       t1_meth.c   t1_srvr.c t1_clnt.c  t1_lib.c  t1_enc.c t1_ext.c \
        d1_meth.c   d1_srvr.c d1_clnt.c  d1_lib.c  d1_pkt.c \
        d1_both.c d1_enc.c d1_srtp.c \
        ssl_lib.c ssl_err2.c ssl_cert.c ssl_sess.c \
@@ -35,7 +35,7 @@ LIBOBJ= \
        s2_meth.o  s2_srvr.o  s2_clnt.o  s2_lib.o  s2_enc.o s2_pkt.o \
        s3_meth.o  s3_srvr.o  s3_clnt.o  s3_lib.o  s3_enc.o s3_pkt.o s3_both.o s3_cbc.o \
        s23_meth.o s23_srvr.o s23_clnt.o s23_lib.o          s23_pkt.o \
-       t1_meth.o   t1_srvr.o t1_clnt.o  t1_lib.o  t1_enc.o \
+       t1_meth.o   t1_srvr.o t1_clnt.o  t1_lib.o  t1_enc.o t1_ext.o \
        d1_meth.o   d1_srvr.o d1_clnt.o  d1_lib.o  d1_pkt.o \
        d1_both.o d1_enc.o d1_srtp.o\
        ssl_lib.o ssl_err2.o ssl_cert.o ssl_sess.o \
@@ -997,6 +997,26 @@ t1_enc.o: ../include/openssl/ssl3.h ../include/openssl/stack.h
 t1_enc.o: ../include/openssl/symhacks.h ../include/openssl/tls1.h
 t1_enc.o: ../include/openssl/x509.h ../include/openssl/x509_vfy.h ssl_locl.h
 t1_enc.o: t1_enc.c
+t1_ext.o: ../e_os.h ../include/openssl/asn1.h ../include/openssl/bio.h
+t1_ext.o: ../include/openssl/buffer.h ../include/openssl/comp.h
+t1_ext.o: ../include/openssl/crypto.h ../include/openssl/dsa.h
+t1_ext.o: ../include/openssl/dtls1.h ../include/openssl/e_os2.h
+t1_ext.o: ../include/openssl/ec.h ../include/openssl/ecdh.h
+t1_ext.o: ../include/openssl/ecdsa.h ../include/openssl/err.h
+t1_ext.o: ../include/openssl/evp.h ../include/openssl/hmac.h
+t1_ext.o: ../include/openssl/kssl.h ../include/openssl/lhash.h
+t1_ext.o: ../include/openssl/obj_mac.h ../include/openssl/objects.h
+t1_ext.o: ../include/openssl/opensslconf.h ../include/openssl/opensslv.h
+t1_ext.o: ../include/openssl/ossl_typ.h ../include/openssl/pem.h
+t1_ext.o: ../include/openssl/pem2.h ../include/openssl/pkcs7.h
+t1_ext.o: ../include/openssl/pqueue.h ../include/openssl/rsa.h
+t1_ext.o: ../include/openssl/safestack.h ../include/openssl/sha.h
+t1_ext.o: ../include/openssl/srtp.h ../include/openssl/ssl.h
+t1_ext.o: ../include/openssl/ssl2.h ../include/openssl/ssl23.h
+t1_ext.o: ../include/openssl/ssl3.h ../include/openssl/stack.h
+t1_ext.o: ../include/openssl/symhacks.h ../include/openssl/tls1.h
+t1_ext.o: ../include/openssl/x509.h ../include/openssl/x509_vfy.h ssl_locl.h
+t1_ext.o: t1_ext.c
 t1_lib.o: ../e_os.h ../include/openssl/asn1.h ../include/openssl/bio.h
 t1_lib.o: ../include/openssl/bn.h ../include/openssl/buffer.h
 t1_lib.o: ../include/openssl/comp.h ../include/openssl/conf.h
index 903f128..deb1863 100644 (file)
@@ -368,7 +368,7 @@ static int ssl23_client_hello(SSL *s)
                if (s->ctx->tlsext_opaque_prf_input_callback != 0 || s->tlsext_opaque_prf_input != NULL)
                        ssl2_compat = 0;
 #endif
-               if (s->cert->custom_cli_ext_records_count != 0)
+               if (s->cert->cli_ext.meths_count != 0)
                        ssl2_compat = 0;
                }
 #endif
index 5f542d1..2705c7c 100644 (file)
--- a/ssl/ssl.h
+++ b/ssl/ssl.h
@@ -409,21 +409,21 @@ typedef int (*tls_session_secret_cb_fn)(SSL *s, void *secret, int *secret_len, S
  *   "al" is a TLS "AlertDescription" from 0-255 which WILL be sent as a 
  *     fatal TLS alert, if the callback returns zero.
  */
-typedef int (*custom_cli_ext_first_cb_fn)(SSL *s, unsigned short ext_type,
+
+typedef int (*custom_ext_add_cb)(SSL *s, unsigned short ext_type,
                                          const unsigned char **out,
-                                         unsigned short *outlen, int *al, void *arg);
-typedef int (*custom_cli_ext_second_cb_fn)(SSL *s, unsigned short ext_type,
+                                         unsigned short *outlen, int *al,
+                                          void *arg);
+
+typedef int (*custom_ext_parse_cb)(SSL *s, unsigned short ext_type,
                                           const unsigned char *in,
                                           unsigned short inlen, int *al,
                                           void *arg);
 
-typedef int (*custom_srv_ext_first_cb_fn)(SSL *s, unsigned short ext_type,
-                                         const unsigned char *in,
-                                         unsigned short inlen, int *al,
-                                         void *arg);
-typedef int (*custom_srv_ext_second_cb_fn)(SSL *s, unsigned short ext_type,
-                                          const unsigned char **out,
-                                          unsigned short *outlen, int *al, void *arg);
+typedef custom_ext_add_cb custom_cli_ext_first_cb_fn;
+typedef custom_ext_parse_cb custom_cli_ext_second_cb_fn;
+typedef custom_ext_add_cb custom_srv_ext_second_cb_fn;
+typedef custom_ext_parse_cb custom_srv_ext_first_cb_fn;
 
 #endif
 
index 4504958..505a510 100644 (file)
@@ -424,24 +424,10 @@ CERT *ssl_cert_dup(CERT *cert)
        ret->sec_ex = cert->sec_ex;
 
 #ifndef OPENSSL_NO_TLSEXT
-       if (cert->custom_cli_ext_records_count)
-               {
-               ret->custom_cli_ext_records = BUF_memdup(cert->custom_cli_ext_records, sizeof(custom_cli_ext_record) * cert->custom_cli_ext_records_count);
-               if (ret->custom_cli_ext_records == NULL)
-                       goto err;
-               ret->custom_cli_ext_records_count =
-                                       cert->custom_cli_ext_records_count;
-               }
-
-       if (cert->custom_srv_ext_records_count)
-               {
-               ret->custom_srv_ext_records = BUF_memdup(cert->custom_srv_ext_records, sizeof(custom_srv_ext_record) * cert->custom_srv_ext_records_count);
-               if (ret->custom_srv_ext_records == NULL)
-                       goto err;
-               ret->custom_srv_ext_records_count =
-                                       cert->custom_srv_ext_records_count;
-               }
-
+       if (!custom_exts_copy(&ret->cli_ext, &cert->cli_ext))
+               goto err;
+       if (!custom_exts_copy(&ret->srv_ext, &cert->srv_ext))
+               goto err;
 #endif
 
        return(ret);
@@ -463,10 +449,8 @@ err:
 #endif
 
 #ifndef OPENSSL_NO_TLSEXT
-       if (ret->custom_cli_ext_records)
-               OPENSSL_free(ret->custom_cli_ext_records);
-       if (ret->custom_srv_ext_records)
-               OPENSSL_free(ret->custom_srv_ext_records);
+       custom_exts_free(&ret->cli_ext);
+       custom_exts_free(&ret->srv_ext);
 #endif
 
        ssl_cert_clear_certs(ret);
@@ -560,10 +544,8 @@ void ssl_cert_free(CERT *c)
        if (c->ciphers_raw)
                OPENSSL_free(c->ciphers_raw);
 #ifndef OPENSSL_NO_TLSEXT
-       if (c->custom_cli_ext_records)
-               OPENSSL_free(c->custom_cli_ext_records);
-       if (c->custom_srv_ext_records)
-               OPENSSL_free(c->custom_srv_ext_records);
+       custom_exts_free(&c->cli_ext);
+       custom_exts_free(&c->srv_ext);
 #endif
        OPENSSL_free(c);
        }
index 98f4018..6a33b9d 100644 (file)
@@ -1751,76 +1751,6 @@ void SSL_CTX_set_next_proto_select_cb(SSL_CTX *ctx, int (*cb) (SSL *s, unsigned
        }
 # endif
 
-static int cert_set_custom_cli_ext(CERT *cert, unsigned short ext_type,
-                              custom_cli_ext_first_cb_fn fn1, 
-                              custom_cli_ext_second_cb_fn fn2, void* arg)
-       {
-       size_t i;
-       custom_cli_ext_record* record;
-
-       /* Check for duplicates */
-       for (i=0; i < cert->custom_cli_ext_records_count; i++)
-               if (ext_type == cert->custom_cli_ext_records[i].ext_type)
-                       return 0;
-
-       cert->custom_cli_ext_records = OPENSSL_realloc(cert->custom_cli_ext_records,
-                                                     (cert->custom_cli_ext_records_count + 1) * 
-                                                     sizeof(custom_cli_ext_record));
-       if (!cert->custom_cli_ext_records) {
-               cert->custom_cli_ext_records_count = 0;
-               return 0;
-       }
-       cert->custom_cli_ext_records_count++;
-       record = &cert->custom_cli_ext_records[cert->custom_cli_ext_records_count - 1];
-       record->ext_type = ext_type;
-       record->fn1 = fn1;
-       record->fn2 = fn2;
-       record->arg = arg;
-       return 1;
-       }
-
-static int cert_set_custom_srv_ext(CERT *cert, unsigned short ext_type,
-                              custom_srv_ext_first_cb_fn fn1, 
-                              custom_srv_ext_second_cb_fn fn2, void* arg)
-       {
-       size_t i;
-       custom_srv_ext_record* record;
-
-       /* Check for duplicates */      
-       for (i=0; i < cert->custom_srv_ext_records_count; i++)
-               if (ext_type == cert->custom_srv_ext_records[i].ext_type)
-                       return 0;
-
-       cert->custom_srv_ext_records = OPENSSL_realloc(cert->custom_srv_ext_records,
-                                                     (cert->custom_srv_ext_records_count + 1) * 
-                                                     sizeof(custom_srv_ext_record));
-       if (!cert->custom_srv_ext_records) {
-               cert->custom_srv_ext_records_count = 0;
-               return 0;
-       }
-       cert->custom_srv_ext_records_count++;
-       record = &cert->custom_srv_ext_records[cert->custom_srv_ext_records_count - 1];
-       record->ext_type = ext_type;
-       record->fn1 = fn1;
-       record->fn2 = fn2;
-       record->arg = arg;
-       return 1;
-       }
-int SSL_CTX_set_custom_cli_ext(SSL_CTX *ctx, unsigned short ext_type,
-                              custom_cli_ext_first_cb_fn fn1, 
-                              custom_cli_ext_second_cb_fn fn2, void *arg)
-       {
-       return cert_set_custom_cli_ext(ctx->cert, ext_type, fn1, fn2,arg);
-       }
-
-int SSL_CTX_set_custom_srv_ext(SSL_CTX *ctx, unsigned short ext_type,
-                              custom_srv_ext_first_cb_fn fn1, 
-                              custom_srv_ext_second_cb_fn fn2, void *arg)
-       {
-       return cert_set_custom_srv_ext(ctx->cert, ext_type, fn1, fn2,arg);
-       }
-
 /* SSL_CTX_set_alpn_protos sets the ALPN protocol list on |ctx| to |protos|.
  * |protos| must be in wire-format (i.e. a series of non-empty, 8-bit
  * length-prefixed strings).
@@ -3645,7 +3575,6 @@ void *SSL_CTX_get0_security_ex_data(const SSL_CTX *ctx)
        return ctx->cert->sec_ex;
        }
 
-
 #if defined(_WINDLL) && defined(OPENSSL_SYS_WIN16)
 #include "../crypto/bio/bss_file.c"
 #endif
index 4a12aec..3bd50df 100644 (file)
@@ -534,17 +534,15 @@ typedef struct cert_pkey_st
 
 typedef struct {
        unsigned short ext_type;
-       custom_cli_ext_first_cb_fn fn1
-       custom_cli_ext_second_cb_fn fn2
+       custom_ext_add_cb add_cb
+       custom_ext_parse_cb parse_cb
        void *arg;
-} custom_cli_ext_record;
+} custom_ext_method;
 
 typedef struct {
-       unsigned short ext_type;
-       custom_srv_ext_first_cb_fn fn1; 
-       custom_srv_ext_second_cb_fn fn2; 
-       void *arg;
-} custom_srv_ext_record;
+       custom_ext_method *meths;
+       size_t meths_count;
+} custom_ext_methods;
 
 typedef struct cert_st
        {
@@ -642,12 +640,9 @@ typedef struct cert_st
        unsigned char *ciphers_raw;
        size_t ciphers_rawlen;
 
-       /* Arrays containing the callbacks for custom TLS Extensions. */
-       custom_cli_ext_record *custom_cli_ext_records;
-       size_t custom_cli_ext_records_count;
-       custom_srv_ext_record *custom_srv_ext_records;
-       size_t custom_srv_ext_records_count;
-
+       /* Custom extension methods for server and client */
+       custom_ext_methods cli_ext;
+       custom_ext_methods srv_ext;
        /* Security callback */
        int (*sec_cb)(SSL *s, SSL_CTX *ctx, int op, int bits, int nid, void *other, void *ex);
        /* Security level */
@@ -1413,6 +1408,21 @@ void tls_fips_digest_extra(
 
 int srp_verify_server_param(SSL *s, int *al);
 
+/* t1_ext.c */
+
+int custom_ext_parse(SSL *s, int server,
+                       unsigned short ext_type,
+                       const unsigned char *ext_data, 
+                       unsigned short ext_size,
+                       int *al);
+int custom_ext_add(SSL *s, int server,
+                       unsigned char **pret,
+                       unsigned char *limit,
+                       int *al);
+
+int custom_exts_copy(custom_ext_methods *dst, const custom_ext_methods *src);
+void custom_exts_free(custom_ext_methods *exts);
+
 #else
 
 #define ssl_init_wbio_buffer SSL_test_functions()->p_ssl_init_wbio_buffer
diff --git a/ssl/t1_ext.c b/ssl/t1_ext.c
new file mode 100644 (file)
index 0000000..ba6d3de
--- /dev/null
@@ -0,0 +1,209 @@
+/* ssl/t1_ext.c */
+/* ====================================================================
+ * Copyright (c) 2014 The OpenSSL Project.  All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ *
+ * 1. Redistributions of source code must retain the above copyright
+ *    notice, this list of conditions and the following disclaimer.
+ *
+ * 2. Redistributions in binary form must reproduce the above copyright
+ *    notice, this list of conditions and the following disclaimer in
+ *    the documentation and/or other materials provided with the
+ *    distribution.
+ *
+ * 3. All advertising materials mentioning features or use of this
+ *    software must display the following acknowledgment:
+ *    "This product includes software developed by the OpenSSL Project
+ *    for use in the OpenSSL Toolkit. (http://www.openssl.org/)"
+ *
+ * 4. The names "OpenSSL Toolkit" and "OpenSSL Project" must not be used to
+ *    endorse or promote products derived from this software without
+ *    prior written permission. For written permission, please contact
+ *    openssl-core@openssl.org.
+ *
+ * 5. Products derived from this software may not be called "OpenSSL"
+ *    nor may "OpenSSL" appear in their names without prior written
+ *    permission of the OpenSSL Project.
+ *
+ * 6. Redistributions of any form whatsoever must retain the following
+ *    acknowledgment:
+ *    "This product includes software developed by the OpenSSL Project
+ *    for use in the OpenSSL Toolkit (http://www.openssl.org/)"
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE OpenSSL PROJECT ``AS IS'' AND ANY
+ * EXPRESSED OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
+ * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
+ * PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL THE OpenSSL PROJECT OR
+ * ITS CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
+ * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
+ * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
+ * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
+ * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT,
+ * STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
+ * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED
+ * OF THE POSSIBILITY OF SUCH DAMAGE.
+ * ====================================================================
+ *
+ * This product includes cryptographic software written by Eric Young
+ * (eay@cryptsoft.com).  This product includes software written by Tim
+ * Hudson (tjh@cryptsoft.com).
+ *
+ */
+
+/* Custom extension utility functions */
+
+#include "ssl_locl.h"
+
+#ifndef OPENSSL_NO_TLSEXT
+
+/* Find a custom extension from the list */
+
+static custom_ext_method *custom_ext_find(custom_ext_methods *exts,
+                                               unsigned short ext_type)
+       {
+       size_t i;
+       custom_ext_method *meth = exts->meths;
+       for (i = 0; i < exts->meths_count; i++, meth++)
+               {
+               if (ext_type == meth->ext_type)
+                       return meth;
+               }
+       return NULL;
+       }
+
+/* pass received custom extension data to the application for parsing */
+
+int custom_ext_parse(SSL *s, int server,
+                       unsigned short ext_type,
+                       const unsigned char *ext_data, 
+                       unsigned short ext_size,
+                       int *al)
+       {
+       custom_ext_methods *exts = server ? &s->cert->srv_ext : &s->cert->cli_ext;
+       custom_ext_method *meth;
+       meth = custom_ext_find(exts, ext_type);
+       /* If not found or no parse function set, return success */
+       if (!meth || !meth->parse_cb)
+               return 1;
+
+       return meth->parse_cb(s, ext_type, ext_data, ext_size, al, meth->arg);
+       }
+
+/* request custom extension data from the application and add to the
+ * return buffer
+ */
+
+int custom_ext_add(SSL *s, int server,
+                       unsigned char **pret,
+                       unsigned char *limit,
+                       int *al)
+       {
+       custom_ext_methods *exts = server ? &s->cert->srv_ext : &s->cert->cli_ext;
+       custom_ext_method *meth;
+       unsigned char *ret = *pret;
+       size_t i;
+
+       for (i = 0; i < exts->meths_count; i++)
+               {
+               const unsigned char *out = NULL;
+               unsigned short outlen = 0;
+               meth = exts->meths + i;
+
+               /* For servers no callback omits extension,
+                * For clients it sends empty extension.
+                */
+               if (server && !meth->add_cb)
+                       continue;
+               if (meth->add_cb)
+                       {
+                       int cb_retval = 0;
+                       cb_retval = meth->add_cb(s, meth->ext_type,
+                                                       &out, &outlen, al,
+                                                       meth->arg);
+                       if (cb_retval == 0)
+                               return 0; /* error */
+                       if (cb_retval == -1)
+                                       continue; /* skip this extension */
+                       }
+               if (4 > limit - ret || outlen > limit - ret - 4)
+                       return 0;
+               s2n(meth->ext_type, ret);
+               s2n(outlen, ret);
+               if (outlen)
+                       {
+                       memcpy(ret, out, outlen);
+                       ret += outlen;
+                       }
+               }
+       *pret = ret;
+       return 1;
+       }
+
+/* Copy table of custom extensions */
+
+int custom_exts_copy(custom_ext_methods *dst, const custom_ext_methods *src)
+       {
+       if (src->meths_count)
+               {
+               dst->meths = BUF_memdup(src->meths, sizeof(custom_ext_method) * src->meths_count);
+               if (dst->meths == NULL)
+                       return 0;
+               dst->meths_count = src->meths_count;
+               }
+       return 1;
+       }
+
+void custom_exts_free(custom_ext_methods *exts)
+       {
+       if (exts->meths)
+               OPENSSL_free(exts->meths);
+       }
+
+/* Set callbacks for a custom extension */
+static int custom_ext_set(custom_ext_methods *exts,
+                       unsigned short ext_type,
+                       custom_ext_parse_cb parse_cb,
+                       custom_ext_add_cb add_cb,
+                       void *arg)
+       {
+       custom_ext_method *meth;
+       /* Search for duplicate */
+       if (custom_ext_find(exts, ext_type))
+               return 0;
+       exts->meths = OPENSSL_realloc(exts->meths,
+                                       (exts->meths_count + 1) * sizeof(custom_ext_method));
+
+       if (!exts->meths)
+               {
+               exts->meths_count = 0;
+               return 0;
+               }
+
+       meth = exts->meths + exts->meths_count;
+       meth->parse_cb = parse_cb;
+       meth->add_cb = add_cb;
+       meth->ext_type = ext_type;
+       meth->arg = arg;
+       exts->meths_count++;
+       return 1;
+       }
+
+/* Application level functions to add custom extension callbacks */
+
+int SSL_CTX_set_custom_cli_ext(SSL_CTX *ctx, unsigned short ext_type,
+                              custom_cli_ext_first_cb_fn fn1, 
+                              custom_cli_ext_second_cb_fn fn2, void *arg)
+       {
+       return custom_ext_set(&ctx->cert->cli_ext, ext_type, fn2, fn1, arg);
+       }
+
+int SSL_CTX_set_custom_srv_ext(SSL_CTX *ctx, unsigned short ext_type,
+                              custom_srv_ext_first_cb_fn fn1, 
+                              custom_srv_ext_second_cb_fn fn2, void *arg)
+       {
+       return custom_ext_set(&ctx->cert->srv_ext, ext_type, fn1, fn2, arg);
+       }
+#endif
index 0430eef..7d0774d 100644 (file)
@@ -1482,38 +1482,8 @@ unsigned char *ssl_add_clienthello_tlsext(SSL *s, unsigned char *buf, unsigned c
                 }
 
        /* Add custom TLS Extensions to ClientHello */
-       if (s->cert->custom_cli_ext_records_count)
-               {
-               size_t i;
-               custom_cli_ext_record* record;
-
-               for (i = 0; i < s->cert->custom_cli_ext_records_count; i++)
-                       {
-                       const unsigned char* out = NULL;
-                       unsigned short outlen = 0;
-
-                       record = &s->cert->custom_cli_ext_records[i];
-                       /* NULL callback sends empty extension */ 
-                       /* -1 from callback omits extension */
-                       if (record->fn1)
-                               {
-                               int cb_retval = 0;
-                               cb_retval = record->fn1(s, record->ext_type,
-                                                       &out, &outlen, al,
-                                                       record->arg);
-                               if (cb_retval == 0)
-                                       return NULL; /* error */
-                               if (cb_retval == -1)
-                                       continue; /* skip this extension */
-                               }
-                       if (limit < ret + 4 + outlen)
-                               return NULL;
-                       s2n(record->ext_type, ret);
-                       s2n(outlen, ret);
-                       memcpy(ret, out, outlen);
-                       ret += outlen;
-                       }
-               }
+       if (!custom_ext_add(s, 0, &ret, limit, al))
+               return NULL;
 #ifdef TLSEXT_TYPE_encrypt_then_mac
        s2n(TLSEXT_TYPE_encrypt_then_mac,ret);
        s2n(0,ret);
@@ -1561,8 +1531,6 @@ unsigned char *ssl_add_serverhello_tlsext(SSL *s, unsigned char *buf, unsigned c
        int extdatalen=0;
        unsigned char *orig = buf;
        unsigned char *ret = buf;
-       size_t i;
-       custom_srv_ext_record *record;
 #ifndef OPENSSL_NO_NEXTPROTONEG
        int next_proto_neg_seen;
 #endif
@@ -1746,32 +1714,8 @@ unsigned char *ssl_add_serverhello_tlsext(SSL *s, unsigned char *buf, unsigned c
                        }
                }
 #endif
-
-       for (i = 0; i < s->cert->custom_srv_ext_records_count; i++)
-               {
-               const unsigned char *out = NULL;
-               unsigned short outlen = 0;
-               int cb_retval = 0;
-
-               record = &s->cert->custom_srv_ext_records[i];
-
-               /* NULL callback or -1 omits extension */
-               if (!record->fn2)
-                       continue;
-               cb_retval = record->fn2(s, record->ext_type,
-                                                               &out, &outlen, al,
-                                                               record->arg);
-               if (cb_retval == 0)
-                       return NULL; /* error */
-               if (cb_retval == -1)
-                       continue; /* skip this extension */
-               if (limit < ret + 4 + outlen)
-                       return NULL;
-               s2n(record->ext_type, ret);
-               s2n(outlen, ret);
-               memcpy(ret, out, outlen);
-               ret += outlen;
-               }
+       if (!custom_ext_add(s, 1, &ret, limit, al))
+               return NULL;
 #ifdef TLSEXT_TYPE_encrypt_then_mac
        if (s->s3->flags & TLS1_FLAGS_ENCRYPT_THEN_MAC)
                {
@@ -1963,6 +1907,7 @@ static void ssl_check_for_safari(SSL *s, const unsigned char *data, const unsign
 }
 #endif /* !OPENSSL_NO_EC */
 
+
 static int ssl_scan_clienthello_tlsext(SSL *s, unsigned char **p, unsigned char *d, int n, int *al) 
        {       
        unsigned short type;
@@ -2503,19 +2448,10 @@ static int ssl_scan_clienthello_tlsext(SSL *s, unsigned char **p, unsigned char
                 * so call the callback and record the extension number so that
                 * an appropriate ServerHello may be later returned.
                 */
-               else if (!s->hit && s->cert->custom_srv_ext_records_count)
+               else if (!s->hit)
                        {
-                       custom_srv_ext_record *record;
-
-                       for (i=0; i < s->cert->custom_srv_ext_records_count; i++)
-                               {
-                               record = &s->cert->custom_srv_ext_records[i];
-                               if (type == record->ext_type)
-                                       {
-                                       if (record->fn1 && !record->fn1(s, type, data, size, al, record->arg))
-                                               return 0;
-                                       }                                               
-                               }
+                       if (!custom_ext_parse(s, 1, type, data, size, al))
+                               return 0;
                        }
 #ifdef TLSEXT_TYPE_encrypt_then_mac
                else if (type == TLSEXT_TYPE_encrypt_then_mac)
@@ -2848,22 +2784,8 @@ static int ssl_scan_serverhello_tlsext(SSL *s, unsigned char **p, unsigned char
                /* If this extension type was not otherwise handled, but 
                 * matches a custom_cli_ext_record, then send it to the c
                 * callback */
-               else if (s->cert->custom_cli_ext_records_count)
-                       {
-                       size_t i;
-                       custom_cli_ext_record* record;
-
-                       for (i = 0; i < s->cert->custom_cli_ext_records_count; i++)
-                               {
-                               record = &s->cert->custom_cli_ext_records[i];
-                               if (record->ext_type == type)
-                                       {
-                                       if (record->fn2 && !record->fn2(s, type, data, size, al, record->arg))
-                                               return 0;
-                                       break;
-                                       }
-                               }                       
-                       }
+               else if (!custom_ext_parse(s, 0, type, data, size, al))
+                               return 0;
 #ifdef TLSEXT_TYPE_encrypt_then_mac
                else if (type == TLSEXT_TYPE_encrypt_then_mac)
                        {