Commit 21181889 authored by Matt Caswell's avatar Matt Caswell
Browse files

Copy custom extension flags in a call to SSL_set_SSL_CTX() 



The function SSL_set_SSL_CTX() can be used to swap the SSL_CTX used for
a connection as part of an SNI callback. One result of this is that the
s->cert structure is replaced. However this structure contains information
about any custom extensions that have been loaded. In particular flags are
set indicating whether a particular extension has been received in the
ClientHello. By replacing the s->cert structure we lose the custom
extension flag values, and it appears as if a client has not sent those
extensions.

SSL_set_SSL_CTX() should copy any flags for custom extensions that appear
in both the old and the new cert structure.

Fixes #2180

Reviewed-by: default avatarRich Salz <rsalz@openssl.org>
(Merged from https://github.com/openssl/openssl/pull/3425)
parent cf53cbea

ssl/ssl_lib.c

+6 −0
Original line number Diff line number Diff line
@@ -3596,6 +3596,12 @@ SSL_CTX *SSL_set_SSL_CTX(SSL *ssl, SSL_CTX *ctx) 
    if (new_cert == NULL) {

        return NULL;

    }



    if (!custom_exts_copy_flags(&new_cert->custext, &ssl->cert->custext)) {

        ssl_cert_free(new_cert);

        return NULL;

    }



    ssl_cert_free(ssl->cert);

    ssl->cert = new_cert;

ssl/ssl_locl.h

+2 −0
Original line number Diff line number Diff line
@@ -2470,6 +2470,8 @@ __owur int custom_ext_add(SSL *s, int context, WPACKET *pkt, X509 *x, 


__owur int custom_exts_copy(custom_ext_methods *dst,

                            const custom_ext_methods *src);

__owur int custom_exts_copy_flags(custom_ext_methods *dst,

                                  const custom_ext_methods *src);

void custom_exts_free(custom_ext_methods *exts);



void ssl_comp_free_compression_methods_int(void);

ssl/statem/extensions_cust.c

+20 −0
Original line number Diff line number Diff line
@@ -231,6 +231,26 @@ int custom_ext_add(SSL *s, int context, WPACKET *pkt, X509 *x, size_t chainidx, 
    return 1;

}



/* Copy the flags from src to dst for any extensions that exist in both */

int custom_exts_copy_flags(custom_ext_methods *dst,

                           const custom_ext_methods *src)

{

    size_t i;

    custom_ext_method *methsrc = src->meths;



    for (i = 0; i < src->meths_count; i++, methsrc++) {

        custom_ext_method *methdst = custom_ext_find(dst, methsrc->role,

                                                     methsrc->ext_type, NULL);



        if (methdst == NULL)

            continue;



        methdst->ext_flags = methsrc->ext_flags;

    }



    return 1;

}



/* Copy table of custom extensions */

int custom_exts_copy(custom_ext_methods *dst, const custom_ext_methods *src)

{