Require retained-bank OpenGL policy for trusted co-op sessions

docs/NETPLAY.md

@@ -39,6 +39,17 @@ An optional read-only callback contributes canonical host-owned gameplay state
 to the existing core CRC; digest logs report this as `mod=`. The callback must
 exclude pointers, padding, rendering caches and local-only input state.
 
+`requires_retained_texture_banks` opts a trusted profile into retained GL
+textures during dual-raster netplay. It requires a working OpenGL backend;
+software/Vulkan selections and an unavailable bank implementation are rejected
+before guest boot. Software at 1x remains the authoritative VRAM/GPUREAD/CRC
+source, independent of GL presentation resolution/filter preferences. Retained
+bank pixels replace textures only on the GL image; the software authority still
+samples ordinary VRAM for those commands. This policy follows the X6 co-op
+renderer behavior and does not provide software retained-bank rendering or
+prove visual equivalence to authoritative VRAM. Validate gameplay state and
+GL presentation separately. The flag is part of the session content identity.
+
 For an offline mode whose host state is not serialized, a trusted plugin can
 call `psx_mod_set_savestate_blocked(1)` and `psx_mod_set_rewind_blocked(1)` during
 activation. These policies reset before each new session; save blocking also

overlay_toolchain/include/mod_netplay.h

@@ -25,6 +25,10 @@ typedef struct PSXModNetplayProfile {
     unsigned fixed_aspect_mask; /* bit 0=4:3, 1=16:9, 2=21:9; zero=no policy */
     const char *widescreen_plugin_id; /* Optional forced renderer for wide. */
     PSXModNetplayStateDigest state_digest;
+    /* Require GL retained texture banks. Netplay retains software @1x VRAM
+     * authority, while GL may use immutable banks for presentation. Software
+     * and unsupported GL launches are refused before guest boot. */
+    int requires_retained_texture_banks;
 } PSXModNetplayProfile;
 
 int psx_mod_register_netplay_profile(const PSXModNetplayProfile *profile);
@@ -43,6 +47,10 @@ int psx_mod_netplay_set_aspect(int index);
 int psx_mod_netplay_aspect(void);
 int psx_mod_netplay_has_state_digest(void);
 uint32_t psx_mod_netplay_state_digest(void);
+int psx_mod_netplay_requires_texture_banks(void);
+/* Runtime renderer index: 0=software, 1=OpenGL, 2=Vulkan. No profile leaves
+ * existing renderer policy unchanged; call only for a netplay launch. */
+int psx_mod_netplay_renderer_allowed(int renderer);
 
 #ifdef __cplusplus
 }

runtime/CMakeLists.txt

@@ -28,6 +28,7 @@ if(BUILD_TESTING)
     target_include_directories(mod_netplay_test PRIVATE include)
     add_test(NAME mod_netplay_test COMMAND mod_netplay_test)
     add_test(NAME mod_netplay_wide_test COMMAND mod_netplay_test --wide)
+    add_test(NAME mod_netplay_optional_bank_test COMMAND mod_netplay_test --no-banks)
     add_executable(savestate_title_policy_test tests/test_savestate_title_policy.c
         src/mod_netplay.c src/psx_sha256.c)
     target_include_directories(savestate_title_policy_test PRIVATE include)

runtime/include/mod_netplay.h

@@ -25,6 +25,10 @@ typedef struct PSXModNetplayProfile {
     unsigned fixed_aspect_mask; /* bit 0=4:3, 1=16:9, 2=21:9; zero=no policy */
     const char *widescreen_plugin_id; /* Optional forced renderer for wide. */
     PSXModNetplayStateDigest state_digest;
+    /* Require GL retained texture banks. Netplay retains software @1x VRAM
+     * authority, while GL may use immutable banks for presentation. Software
+     * and unsupported GL launches are refused before guest boot. */
+    int requires_retained_texture_banks;
 } PSXModNetplayProfile;
 
 int psx_mod_register_netplay_profile(const PSXModNetplayProfile *profile);
@@ -43,6 +47,10 @@ int psx_mod_netplay_set_aspect(int index);
 int psx_mod_netplay_aspect(void);
 int psx_mod_netplay_has_state_digest(void);
 uint32_t psx_mod_netplay_state_digest(void);
+int psx_mod_netplay_requires_texture_banks(void);
+/* Runtime renderer index: 0=software, 1=OpenGL, 2=Vulkan. No profile leaves
+ * existing renderer policy unchanged; call only for a netplay launch. */
+int psx_mod_netplay_renderer_allowed(int renderer);
 
 #ifdef __cplusplus
 }

runtime/src/gpu_gl_renderer.c

@@ -80,6 +80,7 @@
 #include "gpu_gl_renderer.h"
 #include "gpu_hd_textures.h"
 #include "mod_texture_banks.h"
+#include "mod_netplay.h"
 #include "frame_interpolation.h"
 #include "render_pass_plan.h"
 #include "render_pass.h"
@@ -5218,7 +5219,13 @@ static int init_gpu_raster(void) {
     return 1;
 }
 
-int gl_renderer_texture_banks_supported(void) { return s_raster_ok && !s_cpu_auth_dual && !s_hd_native_authority; }
+int gl_renderer_texture_banks_supported(void) {
+    /* A trusted title's bank pixels affect GL presentation only. Keep the
+     * existing software @1x VRAM authority during its delay-sync session. */
+    return s_raster_ok && !s_hd_native_authority &&
+           (!s_cpu_auth_dual || (psx_mod_netplay_is_active() &&
+                                psx_mod_netplay_requires_texture_banks()));
+}
 
 int gl_renderer_fit_wide_aspect(int disp_w, int *num, int *den) {
     /* No sync point: pure arithmetic on limits that change only while the

runtime/src/main.cpp

@@ -18047,6 +18047,11 @@ session_reboot:
     }
     memory_init(bios_path_str.c_str());
     if (g_headless_opengl) g_video_renderer = 1;
+    if (net_cfg.enabled && !psx_mod_netplay_renderer_allowed(g_video_renderer)) {
+        std::fprintf(stderr, "psxrecomp: this title's netplay profile requires OpenGL "
+                             "retained textures; select the OpenGL renderer\n");
+        return 1;
+    }
 #ifndef PSX_HAVE_VULKAN
     /* Vulkan was not compiled in (PSX_ENABLE_VULKAN=OFF or no SDK found).
      * Refuse a vulkan request from ANY source (config / CLI / launcher seed)
@@ -18884,6 +18889,12 @@ session_reboot:
     log_present_cadence();
   }
 
+    if (net_cfg.enabled && psx_mod_netplay_requires_texture_banks() &&
+        !psx_mod_texture_banks_supported()) {
+        std::fprintf(stderr, "psxrecomp: this title's netplay profile requires "
+                             "OpenGL retained texture banks; the backend is unavailable\n");
+        return 1;
+    }
     /* Register vblank presentation callback. */
     gpu_set_vblank_callback(sdl_vblank_present);
 

runtime/src/mod_netplay.c

@@ -53,7 +53,7 @@ int psx_mod_netplay_content_identity(const char *execution_content, char out[65]
     char normalized[65];
     size_t n = strlen(input), i;
     psx_sha256_ctx ctx;
-    uint8_t bytes[32], policy[5];
+    uint8_t bytes[32], policy[6];
     static const char domain[] = "psx-trusted-netplay-profile-v1";
     static const char hex[] = "0123456789abcdef";
     const char *renderer;
@@ -75,6 +75,7 @@ int psx_mod_netplay_content_identity(const char *execution_content, char out[65]
     policy[2] = title_profile->rollback_supported != 0;
     policy[3] = title_profile->savestates_supported != 0;
     policy[4] = title_profile->skip_bios_intro != 0;
+    policy[5] = title_profile->requires_retained_texture_banks != 0;
     psx_sha256_init(&ctx);
     psx_sha256_update(&ctx, (const uint8_t*)domain, sizeof(domain));
     psx_sha256_update(&ctx, (const uint8_t*)normalized, n + 1);
@@ -105,3 +106,9 @@ int psx_mod_netplay_has_state_digest(void) {
 uint32_t psx_mod_netplay_state_digest(void) {
     return psx_mod_netplay_has_state_digest() ? title_profile->state_digest() : 0u;
 }
+int psx_mod_netplay_requires_texture_banks(void) {
+    return title_profile && title_profile->requires_retained_texture_banks != 0;
+}
+int psx_mod_netplay_renderer_allowed(int renderer) {
+    return !psx_mod_netplay_requires_texture_banks() || renderer == 1;
+}

runtime/tests/gpu_hd_texture_stubs.inc

@@ -1,5 +1,9 @@
 /* Existing GL fixtures deliberately run without any external pack. The HD
  * fixture links the real session adapter instead. */
+/* These renderer fixtures also run without a trusted title profile. */
+static int test_title_profile_active, test_title_profile_banks;
+int psx_mod_netplay_is_active(void) { return test_title_profile_active; }
+int psx_mod_netplay_requires_texture_banks(void) { return test_title_profile_banks; }
 #ifndef PSX_TEST_HD_TEXTURE_PACK
 int gpu_hd_textures_acquire_draw(uint16_t tp, uint16_t cx, uint16_t cy,
     const int limits[4], uint32_t window, int semi, GpuHdTextureImage* image) {

runtime/tests/test_gl_readback_region.c

@@ -526,6 +526,29 @@ int main(int argc,char **argv){
  for(test_full_composite=0;test_full_composite<2;test_full_composite++){verify_wide_overlay_band();verify_wide_overlay_order();}
  test_full_composite=0;
  verify_presentation_capture();
+ /* A trusted retained-bank profile permits GL presentation in delay-sync,
+  * while the software authority still samples the original guest texture. */
+ gl_renderer_sync_cpu();
+ gl_renderer_set_cpu_auth_dual(1);
+ check(!gl_renderer_texture_banks_supported(),"dual banks refused without profile");
+ test_title_profile_banks=1;
+ check(!gl_renderer_texture_banks_supported(),"dual banks refused for inactive profile");
+ test_title_profile_active=1;
+ check(gl_renderer_texture_banks_supported(),"trusted dual retained-bank profile allowed");
+ test_title_profile_banks=0;
+ check(!gl_renderer_texture_banks_supported(),"active profile must explicitly request banks");
+ test_title_profile_banks=1;
+ s_hd_native_authority=1;
+ check(!gl_renderer_texture_banks_supported(),"HD authority still refuses retained banks");
+ s_hd_native_authority=0;
+ glb_set_draw_area(0,0,1023,511);
+ glb_vram_write(0,0,0x7c00);
+ check(gl_renderer_select_texture_bank(7),"trusted dual bank selected");
+ glb_draw_shaded_textured_triangle(100,300,0,0,0x808080,132,300,0,0,0x808080,100,332,0,0,0x808080,0,0,0x100,1);
+ check(gl_renderer_select_texture_bank(0),"reset trusted dual bank");
+ check(glb_vram_read(102,302)==0x7c00,"dual software authority samples ordinary VRAM");
+ test_title_profile_active=test_title_profile_banks=0;
+ gl_renderer_set_cpu_auth_dual(0);
  printf("checks=%d failures=%d\n",checks,failures);
  gl_renderer_shutdown();SDL_DestroyWindow(win);SDL_Quit();return failures?1:0;
 }

runtime/tests/test_mod_netplay.c

@@ -48,9 +48,10 @@ int main(int argc, char** argv) {
     NetplayCoreParts baseline, live, changed;
     PSXModNetplayProfile invalid, duplicate;
     static PSXModNetplayProfile profile = {
-        "test.simulation", "test-coop-delay-v1", 0, 0, 1, 1u, NULL, gameplay_digest
+        "test.simulation", "test-coop-delay-v1", 0, 0, 1, 1u, NULL, gameplay_digest, 1
     };
     const int wide = argc > 1 && strcmp(argv[1], "--wide") == 0;
+    const int no_banks = argc > 1 && strcmp(argv[1], "--no-banks") == 0;
     uint32_t original_session, profile_session;
     char original_identity[65], current_identity[65];
     const char* fingerprint =
@@ -60,6 +61,9 @@ int main(int argc, char** argv) {
     netplay_core_digest_parts(&cpu, &baseline);
     assert(baseline.mod == 0);
     assert(psx_mod_netplay_rollback_supported());
+    assert(!psx_mod_netplay_requires_texture_banks());
+    assert(psx_mod_netplay_renderer_allowed(0) && psx_mod_netplay_renderer_allowed(1) &&
+           psx_mod_netplay_renderer_allowed(2));
     assert(psx_mod_netplay_savestates_supported());
     assert(strcmp(psx_mod_netplay_version("dev"), "dev") == 0);
     assert(psx_mod_netplay_session_id(123) == 123);
@@ -81,11 +85,17 @@ int main(int argc, char** argv) {
     invalid.fixed_aspect_mask = 8u;
     assert(!psx_mod_register_netplay_profile(&invalid));
     if (wide) profile.fixed_aspect_mask = 6u;
+    if (no_banks) profile.requires_retained_texture_banks = 0;
     assert(psx_mod_register_netplay_profile(&profile));
     assert(psx_mod_register_netplay_profile(&profile));
     duplicate = profile;
     assert(!psx_mod_register_netplay_profile(&duplicate));
     assert(!psx_mod_netplay_rollback_supported());
+    assert(psx_mod_netplay_requires_texture_banks() == !no_banks);
+    assert(psx_mod_netplay_renderer_allowed(1));
+    assert(psx_mod_netplay_renderer_allowed(0) == no_banks);
+    assert(psx_mod_netplay_renderer_allowed(2) == no_banks);
+    assert(psx_mod_netplay_renderer_allowed(-1) == no_banks);
     assert(psx_mod_netplay_savestates_supported());
     assert(strcmp(psx_mod_netplay_version("override"), "test-coop-delay-v1") == 0);
     assert(psx_mod_netplay_aspect() == (wide ? 1 : 0));

runtime/tests/test_mod_runtime.cpp

@@ -1755,7 +1755,7 @@ int main(int argc, char** argv) {
     static const PSXModNetplayProfile profile = {
         missing_profile ? "runtime.missing-simulation" : "runtime.test-vblank",
         "runtime-coop-delay-v1", 0, 0, 1, 3u,
-        "runtime.missing-renderer", nullptr
+        "runtime.missing-renderer", nullptr, 0
     };
     check(psx_mod_register_netplay_profile(&profile), "trusted profile registration");
     check(PSXRecompV4::mod_runtime_initialize(root, "SLUS-RUNTIME", 0x80002000, {}, &error),

runtime/tests/test_savestate_title_policy.c

@@ -57,7 +57,7 @@ int main(void) {
     CPUState cpu;
     const uint8_t blob = 1;
     static const PSXModNetplayProfile profile = {
-        "test.simulation", "test-no-snapshots-v1", 0, 0, 0, 1u, NULL, NULL
+        "test.simulation", "test-no-snapshots-v1", 0, 0, 0, 1u, NULL, NULL, 0
     };
     memset(&cpu, 0, sizeof(cpu));
     s_configured = 1; /* No configure/filesystem needed to test request staging. */