Fix Patch RomFS ctx init w/missing base NCA FS.

This bug was introduced in c474435ea8.

Other changes include:

* nxdt_rw_poc, bktr: minor cosmetic code changes.
* cnmt: add ContentMetaPlatform enum.

code_templates/nxdt_rw_poc.c

@@ -934,7 +934,7 @@ int main(int argc, char *argv[])
         }
 
         consoleClear();
-        consolePrint(APP_TITLE " v" APP_VERSION " (" GIT_REV "). Built on " BUILD_TIMESTAMP ".\n");
+        consolePrint(APP_TITLE " v" APP_VERSION " (" GIT_REV ").\nBuilt on " BUILD_TIMESTAMP ".\n");
         consolePrint("______________________________\n\n");
         if (cur_menu->parent) consolePrint("press b to go back\n");
         if (g_umsDeviceCount) consolePrint("press x to safely remove all ums devices\n");

include/core/cnmt.h

@@ -41,6 +41,11 @@ typedef enum {
     ContentMetaAttribute_Count               = 3        ///< Total values supported by this enum.
 } ContentMetaAttribute;
 
+typedef enum {
+    ContentMetaPlatform_Nx    = 0,
+    ContentMetaPlatform_Count = 1   ///< Total values supported by this enum.
+} ContentMetaPlatform;
+
 typedef enum {
     ContentMetaInstallState_None      = 0,
     ContentMetaInstallState_Committed = BIT(0),
@@ -56,7 +61,7 @@ typedef struct {
     u64 title_id;
     Version version;
     u8 content_meta_type;                       ///< NcmContentMetaType.
-    u8 reserved_1;
+    u8 content_meta_platform;                   ///< ContentMetaPlatform.
     u16 extended_header_size;                   ///< Must match the size from the extended header struct for this content meta type (SystemUpdate, Application, Patch, AddOnContent, Delta).
     u16 content_count;                          ///< Determines how many NcmPackagedContentInfo entries are available after the extended header.
     u16 content_meta_count;                     ///< Determines how many NcmContentMetaInfo entries are available after the NcmPackagedContentInfo entries. Only used for SystemUpdate.
@@ -65,7 +70,7 @@ typedef struct {
     u8 content_install_type;                    ///< NcmContentInstallType.
     u8 install_state;                           ///< ContentMetaInstallState.
     Version required_download_system_version;
-    u8 reserved_2[0x4];
+    u8 reserved[0x4];
 } ContentMetaPackagedContentMetaHeader;
 
 NXDT_ASSERT(ContentMetaPackagedContentMetaHeader, 0x20);

include/core/nca_storage.h

@@ -50,9 +50,8 @@ typedef struct {
 } NcaStorageContext;
 
 /// Initializes a NCA storage context using a NCA FS section context, optionally providing a pointer to a base NcaStorageContext.
-/// 'base_ctx' must be provided if dealing with a patch NCA. One of its storages will be set as the original substorage for the initialized NcaStorageContext's Indirect Storage.
+/// 'base_ctx' shall be provided if dealing with a patch NCA with available base NCA data. This is needed to perform combined reads between a base NCA and a patch NCA.
-/// This is needed to perform combined reads between a base NCA and a patch NCA.
+/// 'base_ctx' shall be NULL if dealing with a base NCA *or* a patch NCA with missing base NCA data.
-/// 'base_ctx' shall be NULL if dealing with a base NCA.
 bool ncaStorageInitializeContext(NcaStorageContext *out, NcaFsSectionContext *nca_fs_ctx, NcaStorageContext *base_ctx);
 
 /// Retrieves the underlying NCA FS section's hierarchical hash target layer extents. Virtual extents may be returned, depending on the base storage type.

source/core/bktr.c

@@ -1138,8 +1138,8 @@ static bool bktrReadCompressedStorage(BucketTreeVisitor *visitor, void *out, u64
                 }
 
                 /* Decompress LZ4 block. */
-                int lz4_res = 0;
+                int lz4_res = LZ4_decompress_safe((char*)read_ptr, (char*)buffer, (int)compressed_data_size, (int)buffer_size);
-                if ((lz4_res = LZ4_decompress_safe((char*)read_ptr, (char*)buffer, (int)compressed_data_size, (int)buffer_size)) != (int)decompressed_data_size)
+                if (lz4_res != (int)decompressed_data_size)
                 {
                     LOG_MSG_ERROR("Failed to decompress 0x%lX-byte long compressed block! (%d).", compressed_data_size, lz4_res);
                     free(buffer);

source/core/cnmt.c

@@ -146,6 +146,12 @@ bool cnmtInitializeContext(ContentMetaContext *out, NcaContext *nca_ctx)
         goto end;
     }
 
+    if (out->packaged_header->content_meta_platform >= ContentMetaPlatform_Count)
+    {
+        LOG_MSG_ERROR("Invalid platform!");
+        goto end;
+    }
+
     if (!out->packaged_header->content_count && out->packaged_header->content_meta_type != NcmContentMetaType_SystemUpdate)
     {
         LOG_MSG_ERROR("Invalid content count!");

source/core/nca_storage.c

@@ -25,13 +25,13 @@
 /* Function prototypes. */
 
 static bool ncaStorageInitializeBucketTreeContext(BucketTreeContext **out, NcaFsSectionContext *nca_fs_ctx, u8 storage_type);
-static bool ncaStorageSetPatchOriginalSubStorage(NcaStorageContext *patch_ctx, NcaFsSectionContext *patch_nca_fs_ctx, NcaStorageContext *base_ctx);
+static bool ncaStorageSetPatchOriginalSubStorage(NcaStorageContext *patch_ctx, NcaStorageContext *base_ctx);
 static bool ncaStorageInitializeCompressedStorageBucketTreeContext(NcaStorageContext *out, NcaFsSectionContext *nca_fs_ctx);
 
 bool ncaStorageInitializeContext(NcaStorageContext *out, NcaFsSectionContext *nca_fs_ctx, NcaStorageContext *base_ctx)
 {
     if (!out || !nca_fs_ctx || !nca_fs_ctx->enabled || (nca_fs_ctx->section_type == NcaFsSectionType_PatchRomFs && \
-        (!nca_fs_ctx->has_patch_indirect_layer || !nca_fs_ctx->has_patch_aes_ctr_ex_layer || nca_fs_ctx->has_sparse_layer || !base_ctx)))
+        (!nca_fs_ctx->has_patch_indirect_layer || !nca_fs_ctx->has_patch_aes_ctr_ex_layer || nca_fs_ctx->has_sparse_layer)))
     {
         LOG_MSG_ERROR("Invalid parameters!");
         return false;
@@ -61,7 +61,7 @@ bool ncaStorageInitializeContext(NcaStorageContext *out, NcaFsSectionContext *nc
     /* Check if both Indirect and AesCtrEx layers are available. */
     if (nca_fs_ctx->section_type == NcaFsSectionType_PatchRomFs)
     {
-        /* Initialize AesCtrEx and Indirect layers. */
+        /* Initialize AesCtrEx layer. */
         if (!ncaStorageInitializeBucketTreeContext(&(out->aes_ctr_ex_storage), nca_fs_ctx, BucketTreeStorageType_AesCtrEx) || \
             !ncaStorageInitializeBucketTreeContext(&(out->indirect_storage), nca_fs_ctx, BucketTreeStorageType_Indirect)) goto end;
 
@@ -69,8 +69,8 @@ bool ncaStorageInitializeContext(NcaStorageContext *out, NcaFsSectionContext *nc
         if (!bktrSetRegularSubStorage(out->aes_ctr_ex_storage, nca_fs_ctx)) goto end;
 
         /* Set Indirect layer's substorages (Base + AesCtrEx). */
-        if (!ncaStorageSetPatchOriginalSubStorage(out, nca_fs_ctx, base_ctx)) goto end;
+        if (!ncaStorageSetPatchOriginalSubStorage(out, base_ctx) || \
-        if (!bktrSetBucketTreeSubStorage(out->indirect_storage, out->aes_ctr_ex_storage, 1)) goto end;
+            !bktrSetBucketTreeSubStorage(out->indirect_storage, out->aes_ctr_ex_storage, 1)) goto end;
 
         /* Update base storage type. */
         out->base_storage_type = NcaStorageBaseStorageType_Indirect;
@@ -261,21 +261,27 @@ end:
     return success;
 }
 
-static bool ncaStorageSetPatchOriginalSubStorage(NcaStorageContext *patch_ctx, NcaFsSectionContext *patch_nca_fs_ctx, NcaStorageContext *base_ctx)
+static bool ncaStorageSetPatchOriginalSubStorage(NcaStorageContext *patch_ctx, NcaStorageContext *base_ctx)
 {
+    NcaFsSectionContext *patch_nca_fs_ctx = NULL, *base_nca_fs_ctx = NULL;
     NcaContext *patch_nca_ctx = NULL, *base_nca_ctx = NULL;
 
-    if (!patch_ctx || !patch_ctx->indirect_storage || !patch_ctx->aes_ctr_ex_storage || !patch_nca_fs_ctx || !ncaStorageIsValidContext(base_ctx) || \
+    bool missing_base_ctx = !ncaStorageIsValidContext(base_ctx);
-        !(patch_nca_ctx = patch_nca_fs_ctx->nca_ctx) || !(base_nca_ctx = base_ctx->nca_fs_ctx->nca_ctx) || \
+
-        patch_nca_fs_ctx->section_type != NcaFsSectionType_PatchRomFs || base_ctx->nca_fs_ctx->section_type != NcaFsSectionType_RomFs || \
+    bool success = false;
+
+    if (!patch_ctx || !patch_ctx->indirect_storage || !patch_ctx->aes_ctr_ex_storage || !(patch_nca_fs_ctx = patch_ctx->indirect_storage->nca_fs_ctx) || \
+        patch_nca_fs_ctx->section_type != NcaFsSectionType_PatchRomFs || !(patch_nca_ctx = patch_nca_fs_ctx->nca_ctx) || \
+        (!missing_base_ctx && (!(base_nca_fs_ctx = base_ctx->nca_fs_ctx) || base_nca_fs_ctx->section_type != NcaFsSectionType_RomFs || !(base_nca_ctx = base_nca_fs_ctx->nca_ctx) || \
         patch_nca_ctx->header.program_id != base_nca_ctx->header.program_id || patch_nca_ctx->header.content_type != base_nca_ctx->header.content_type || \
-        patch_nca_ctx->id_offset != base_nca_ctx->id_offset || patch_nca_ctx->title_version.value < base_nca_ctx->title_version.value)
+        patch_nca_ctx->id_offset != base_nca_ctx->id_offset || patch_nca_ctx->title_version.value < base_nca_ctx->title_version.value)))
     {
         LOG_MSG_ERROR("Invalid parameters!");
         return false;
     }
 
-    bool success = false;
+    /* Return immediately if we passed all patch context checks, but we're missing a base context. */
+    if (missing_base_ctx) return true;
 
     /* Set original substorage. */
     switch(base_ctx->base_storage_type)

source/core/romfs.c

@@ -66,7 +66,7 @@ bool romfsInitializeContext(RomFileSystemContext *out, NcaFsSectionContext *base
     if (patch_nca_fs_ctx)
     {
         /* Initialize base NCA storage context. */
-        if (!ncaStorageInitializeContext(patch_storage_ctx, patch_nca_fs_ctx, base_storage_ctx))
+        if (!ncaStorageInitializeContext(patch_storage_ctx, patch_nca_fs_ctx, missing_base_romfs ? NULL : base_storage_ctx))
         {
             LOG_MSG_ERROR("Failed to initialize patch NCA storage context!");
             goto end;