tcptls/iostream: Add support for setting SNI on client TLS connections

If the hostname field of the ast_tcptls_session_args structure is
set (which it is for websocket client connections), that hostname
will now automatically be used in an SNI TLS extension in the client
hello.

Resolves: #713

UserNote: Secure websocket client connections now send SNI in
the TLS client hello.
This commit is contained in:
George Joseph
2024-04-23 14:15:20 -06:00
committed by asterisk-org-access-app[bot]
parent 758ed2b9fd
commit 8e119a72f0
3 changed files with 39 additions and 5 deletions

View File

@@ -46,6 +46,7 @@ struct ast_iostream {
int rbuflen;
char *rbufhead;
char rbuf[2048];
char *sni_hostname;
};
#if defined(DO_SSL)
@@ -152,6 +153,16 @@ void ast_iostream_set_exclusive_input(struct ast_iostream *stream, int exclusive
stream->exclusive_input = exclusive_input;
}
int ast_iostream_set_sni_hostname(struct ast_iostream *stream, const char *sni_hostname)
{
ast_assert(stream != NULL);
ast_free(stream->sni_hostname);
stream->sni_hostname = ast_strdup(sni_hostname);
return stream->sni_hostname ? 0 : -1;
}
static ssize_t iostream_read(struct ast_iostream *stream, void *buf, size_t size)
{
struct timeval start;
@@ -591,13 +602,9 @@ int ast_iostream_close(struct ast_iostream *stream)
static void iostream_dtor(void *cookie)
{
#ifdef AST_DEVMODE
/* Since the ast_assert below is the only one using stream,
* and ast_assert is only available with AST_DEVMODE, we
* put this in a conditional to avoid compiler warnings. */
struct ast_iostream *stream = cookie;
#endif
ast_free(stream->sni_hostname);
ast_assert(stream->fd == -1);
}
@@ -639,6 +646,15 @@ int ast_iostream_start_tls(struct ast_iostream **pstream, SSL_CTX *ssl_ctx, int
*/
SSL_set_fd(stream->ssl, stream->fd);
if (client && !ast_strlen_zero(stream->sni_hostname)) {
if (!SSL_set_tlsext_host_name(stream->ssl, stream->sni_hostname)) {
ast_log(LOG_ERROR, "Unable to set SNI hostname '%s'\n",
stream->sni_hostname);
errno = EIO;
return -1;
}
}
res = ssl_setup(stream->ssl);
if (res <= 0) {
int sslerr = SSL_get_error(stream->ssl, res);