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

[Christophe Fergeau]

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)
+{
+    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_method*)bio->method)->stream))
-#define BIO_GET_OSTREAM(bio)  (g_io_stream_get_output_stream(((bio_gsocket_method*)bio->method)->stream))
+    switch (cmd) {
+    case BIO_CTRL_FLUSH:
+        ret = 1;
+        break;
+    default:
+        ret = 0;
+        break;
+    }
+    return ret;
+}
 
 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(stream),
                                                    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;
+        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;
 }
-- 
2.9.3