[Spice-devel] [spice-gtk 2/3] ssl: Rework our custom BIO type

[Pavel Grunt]

On Thu, 2016-12-22 at 17:03 +0100, Christophe Fergeau wrote:
> From: Sebastian Andrzej Siewior <sebastian at breakpoint.cc>
> 
> This commit changes to an actual new BIO method rather than reusing
> an
> existing BIO method, and overriding only the fields that we need.
> The approach before this commit would be causing issues with OpenSSL
> 1.1.0 as some of the fields we access have become opaque.
> ---
>  src/bio-gio.c | 60 +++++++++++++++++++++++++++++++-----------------
> -----------
>  1 file changed, 32 insertions(+), 28 deletions(-)
> 
> diff --git a/src/bio-gio.c b/src/bio-gio.c
> index b310c97..20ee57a 100644
> --- a/src/bio-gio.c
> +++ b/src/bio-gio.c
> @@ -23,21 +23,29 @@
>  #include "spice-util.h"
>  #include "bio-gio.h"
>  
> -typedef struct bio_gsocket_method {
> -    BIO_METHOD method;
> -    GIOStream *stream;
> -} bio_gsocket_method;
> +static long bio_gio_ctrl(BIO *b, int cmd, long num, void *ptr)
I prefer to mark unused parameters as G_GNUC_UNUSED
> +{
> +    long ret;
>  
> -#define BIO_GET_GSOCKET(bio)  (((bio_gsocket_method*)bio->method)-
> >gsocket)
> -#define
> BIO_GET_ISTREAM(bio)  (g_io_stream_get_input_stream(((bio_gsocket_me
> thod*)bio->method)->stream))
> -#define
> BIO_GET_OSTREAM(bio)  (g_io_stream_get_output_stream(((bio_gsocket_m
> ethod*)bio->method)->stream))
> +    switch (cmd) {
> +    case BIO_CTRL_FLUSH:
> +        ret = 1;
> +        break;
> +    default:
> +        ret = 0;
> +        break;
> +    }
> +    return ret;

return cmd == BIO_CTRL_FLUSH

Should be enough

> +}
>  
>  static int bio_gio_write(BIO *bio, const char *in, int inl)
>  {
> +    GOutputStream *stream;
>      gssize ret;
>      GError *error = NULL;
>  
> -    ret =
> g_pollable_output_stream_write_nonblocking(G_POLLABLE_OUTPUT_STREAM(
> BIO_GET_OSTREAM(bio)),
> +    stream = g_io_stream_get_output_stream(bio->ptr);
> +    ret =
> g_pollable_output_stream_write_nonblocking(G_POLLABLE_OUTPUT_STREAM(
> stream),
>                                                       in, inl, NULL,
> &error);
>      BIO_clear_retry_flags(bio);
>  
> @@ -53,10 +61,12 @@ static int bio_gio_write(BIO *bio, const char
> *in, int inl)
>  
>  static int bio_gio_read(BIO *bio, char *out, int outl)
>  {
> +    GInputStream *stream;
>      gssize ret;
>      GError *error = NULL;
>  
> -    ret =
> g_pollable_input_stream_read_nonblocking(G_POLLABLE_INPUT_STREAM(BIO
> _GET_ISTREAM(bio)),
> +    stream = g_io_stream_get_input_stream(bio->ptr);
> +    ret =
> g_pollable_input_stream_read_nonblocking(G_POLLABLE_INPUT_STREAM(str
> eam),
>                                                     out, outl, NULL,
> &error);
>      BIO_clear_retry_flags(bio);
>  
> @@ -70,17 +80,6 @@ static int bio_gio_read(BIO *bio, char *out, int
> outl)
>      return ret;
>  }
>  
> -static int bio_gio_destroy(BIO *bio)
> -{
> -    if (bio == NULL || bio->method == NULL)
> -        return 0;
> -
> -    SPICE_DEBUG("bio gsocket destroy");
> -    g_clear_pointer(&bio->method, g_free);
> -
> -    return 1;
> -}
> -
>  static int bio_gio_puts(BIO *bio, const char *str)
>  {
>      int n, ret;
> @@ -94,20 +93,25 @@ static int bio_gio_puts(BIO *bio, const char
> *str)
>  G_GNUC_INTERNAL
>  BIO* bio_new_giostream(GIOStream *stream)
>  {
> -    // TODO: make an actual new BIO type, or just switch to GTls
> already...
> -    BIO *bio = BIO_new_socket(-1, BIO_NOCLOSE);
> +    BIO *bio;
> +    static BIO_METHOD bio_gio_method;
>  
> -    bio_gsocket_method *bio_method = g_new(bio_gsocket_method, 1);
> -    bio_method->method = *bio->method;
> -    bio_method->stream = stream;
> +    if (bio_gio_method.name == NULL) {
> +        bio_gio_method.type = 128 | BIO_TYPE_SOURCE_SINK;

What does this 128 mean ? BIO_TYPE_START?

> +        bio_gio_method.name = "gio stream";
> +    }
>  
> -    bio->method->destroy(bio);
> -    bio->method = (BIO_METHOD*)bio_method;
> +    bio = BIO_new(&bio_gio_method);
> +    if (!bio)
> +        return NULL;
>  
>      bio->method->bwrite = bio_gio_write;
>      bio->method->bread = bio_gio_read;
>      bio->method->bputs = bio_gio_puts;
> -    bio->method->destroy = bio_gio_destroy;
> +    bio->method->ctrl = bio_gio_ctrl;
> +
> +    bio->init = 1;
> +    bio->ptr = stream;
>  
>      return bio;
>  }

Pavel