ro: add support for applying ips patches to NROs.

stratosphere/ro/source/ro_patcher.cpp

@@ -0,0 +1,188 @@
+/*
+ * Copyright (c) 2018-2019 Atmosphère-NX
+ *
+ * This program is free software; you can redistribute it and/or modify it
+ * under the terms and conditions of the GNU General Public License,
+ * version 2, as published by the Free Software Foundation.
+ *
+ * This program is distributed in the hope it will be useful, but WITHOUT
+ * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
+ * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License for
+ * more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program.  If not, see <http://www.gnu.org/licenses/>.
+ */
+
+#include <cstdlib>
+#include <cstdint>
+#include <cstdio>
+#include <cstring>
+#include <dirent.h>
+#include <ctype.h>
+
+#include <switch.h>
+#include "ro_patcher.hpp"
+#include "ro_registration.hpp"
+
+/* IPS Patching adapted from Luma3DS (https://github.com/AuroraWright/Luma3DS/blob/master/sysmodules/loader/source/patcher.c) */
+
+#define IPS_MAGIC "PATCH"
+#define IPS_TAIL "EOF"
+
+#define IPS32_MAGIC "IPS32"
+#define IPS32_TAIL "EEOF"
+
+static inline u8 HexNybbleToU8(const char nybble) {
+    if ('0' <= nybble && nybble <= '9') {
+        return nybble - '0';
+    } else if ('a' <= nybble && nybble <= 'f') {
+        return nybble - 'a' + 0xa;
+    } else {
+        return nybble - 'A' + 0xA;
+    }
+}
+
+static bool MatchesBuildId(const char *name, size_t name_len, const u8 *build_id) {
+    /* Validate name is hex build id. */
+    for (unsigned int i = 0; i < name_len - 4; i++) {
+        if (isxdigit(name[i]) == 0) {
+                return false;
+        }
+    }
+
+    /* Read build id from name. */
+    u8 build_id_from_name[0x20] = {0};
+    for (unsigned int name_ofs = 0, id_ofs = 0; name_ofs < name_len - 4; id_ofs++) {
+        build_id_from_name[id_ofs] |= HexNybbleToU8(name[name_ofs++]) << 4;
+        build_id_from_name[id_ofs] |= HexNybbleToU8(name[name_ofs++]);
+    }
+
+    return memcmp(build_id, build_id_from_name, sizeof(build_id_from_name)) == 0;
+}
+
+static void ApplyIpsPatch(u8 *mapped_nro, size_t mapped_size, bool is_ips32, FILE *f_ips) {
+    u8 buffer[4];
+    while (fread(buffer, is_ips32 ? 4 : 3, 1, f_ips) == 1) {
+        if (is_ips32 && memcmp(buffer, IPS32_TAIL, 4) == 0) {
+            break;
+        } else if (!is_ips32 && memcmp(buffer, IPS_TAIL, 3) == 0) {
+            break;
+        }
+
+        /* Offset of patch. */
+        u32 patch_offset;
+        if (is_ips32) {
+           patch_offset = (buffer[0] << 24) | (buffer[1] << 16) | (buffer[2] << 8) | buffer[3];
+        } else {
+           patch_offset = (buffer[0] << 16) | (buffer[1] << 8) | (buffer[2]);
+        }
+
+        /* Size of patch. */
+        if (fread(buffer, 2, 1, f_ips) != 1) {
+            break;
+        }
+        u32 patch_size = (buffer[0] << 8) | (buffer[1]);
+
+        /* Check for RLE encoding. */
+        if (patch_size == 0) {
+            /* Size of RLE. */
+            if (fread(buffer, 2, 1, f_ips) != 1) {
+                break;
+            }
+
+            u32 rle_size = (buffer[0] << 8) | (buffer[1]);
+
+            /* Value for RLE. */
+            if (fread(buffer, 1, 1, f_ips) != 1) {
+                break;
+            }
+
+            if (patch_offset < sizeof(Registration::NroHeader)) {
+                if (patch_offset + rle_size > sizeof(Registration::NroHeader)) {
+                    u32 diff = sizeof(Registration::NroHeader) - patch_offset;
+                    patch_offset += diff;
+                    rle_size -= diff;
+                    goto IPS_RLE_PATCH_OFFSET_WITHIN_BOUNDS;
+                }
+            } else {
+                IPS_RLE_PATCH_OFFSET_WITHIN_BOUNDS:
+                patch_offset -= sizeof(Registration::NroHeader);
+                if (patch_offset + rle_size > mapped_size) {
+                    rle_size = mapped_size - patch_offset;
+                }
+                memset(mapped_nro + patch_offset, buffer[0], rle_size);
+            }
+        } else {
+            if (patch_offset < sizeof(Registration::NroHeader)) {
+                if (patch_offset + patch_size > sizeof(Registration::NroHeader)) {
+                    u32 diff = sizeof(Registration::NroHeader) - patch_offset;
+                    patch_offset += diff;
+                    patch_size -= diff;
+                    fseek(f_ips, diff, SEEK_CUR);
+                    goto IPS_DATA_PATCH_OFFSET_WITHIN_BOUNDS;
+                } else {
+                    fseek(f_ips, patch_size, SEEK_CUR);
+                }
+            } else {
+                IPS_DATA_PATCH_OFFSET_WITHIN_BOUNDS:
+                patch_offset -= sizeof(Registration::NroHeader);
+                u32 read_size = patch_size;
+                if (patch_offset + read_size > mapped_size) {
+                    read_size = mapped_size - patch_offset;
+                }
+                if (fread(mapped_nro + patch_offset, read_size, 1, f_ips) != 1) {
+                    break;
+                }
+                if (patch_size > read_size) {
+                    fseek(f_ips, patch_size - read_size, SEEK_CUR);
+                }
+            }
+        }
+    }
+}
+
+void PatchUtils::ApplyPatches(const ModuleId *module_id, u8 *mapped_nro, size_t mapped_size) {
+    /* Inspect all patches from /atmosphere/nro_patches/<*>/<*>.ips */
+    char path[FS_MAX_PATH+1] = {0};
+    snprintf(path, sizeof(path) - 1, "sdmc:/atmosphere/nro_patches");
+    DIR *patches_dir = opendir(path);
+    struct dirent *pdir_ent;
+    if (patches_dir != NULL) {
+        /* Iterate over the patches directory to find patch subdirectories. */
+        while ((pdir_ent = readdir(patches_dir)) != NULL) {
+            if (strcmp(pdir_ent->d_name, ".") == 0 || strcmp(pdir_ent->d_name, "..") == 0) {
+                continue;
+            }
+            snprintf(path, sizeof(path) - 1, "sdmc:/atmosphere/nro_patches/%s", pdir_ent->d_name);
+            DIR *patch_dir = opendir(path);
+            struct dirent *ent;
+            if (patch_dir != NULL) {
+                /* Iterate over the patch subdirectory to find .ips patches. */
+                while ((ent = readdir(patch_dir)) != NULL) {
+                    if (strcmp(ent->d_name, ".") == 0 || strcmp(ent->d_name, "..") == 0) {
+                        continue;
+                    }
+                    size_t name_len = strlen(ent->d_name);
+                    if ((4 < name_len && name_len <= 0x44) && ((name_len & 1) == 0) && strcmp(ent->d_name + name_len - 4, ".ips") == 0 && MatchesBuildId(ent->d_name, name_len, module_id->build_id)) {
+                        snprintf(path, sizeof(path) - 1, "sdmc:/atmosphere/nro_patches/%s/%s", pdir_ent->d_name, ent->d_name);
+                        FILE *f_ips = fopen(path, "rb");
+                        if (f_ips != NULL) {
+                            u8 header[5];
+                            if (fread(header, 5, 1, f_ips) == 1) {
+                                if (memcmp(header, IPS_MAGIC, 5) == 0) {
+                                    ApplyIpsPatch(mapped_nro, mapped_size, false, f_ips);
+                                } else if (memcmp(header, IPS32_MAGIC, 5) == 0) {
+                                    ApplyIpsPatch(mapped_nro, mapped_size, true, f_ips);
+                                }
+                            }
+                            fclose(f_ips);
+                        }
+                    }
+                }
+                closedir(patch_dir);
+            }
+        }
+        closedir(patches_dir);
+    }
+}

stratosphere/ro/source/ro_patcher.hpp

@@ -0,0 +1,26 @@
+/*
+ * Copyright (c) 2018-2019 Atmosphère-NX
+ *
+ * This program is free software; you can redistribute it and/or modify it
+ * under the terms and conditions of the GNU General Public License,
+ * version 2, as published by the Free Software Foundation.
+ *
+ * This program is distributed in the hope it will be useful, but WITHOUT
+ * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
+ * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License for
+ * more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program.  If not, see <http://www.gnu.org/licenses/>.
+ */
+
+#pragma once
+#include <switch.h>
+#include <cstdio>
+
+#include "ro_types.hpp"
+
+class PatchUtils {
+    public:
+        static void ApplyPatches(const ModuleId *module_id, u8 *mapped_nro, size_t mapped_size);
+};

stratosphere/ro/source/ro_registration.cpp

@@ -22,6 +22,7 @@
 #include "ro_registration.hpp"
 #include "ro_map.hpp"
 #include "ro_nrr.hpp"
+#include "ro_patcher.hpp"
 
 /* Declare process contexts as global array. */
 static Registration::RoProcessContext g_process_contexts[Registration::MaxSessions] = {};
@@ -323,6 +324,9 @@ Result Registration::ValidateNro(ModuleId *out_module_id, u64 *out_rx_size, u64
         }
     }
 
+    /* Apply patches to NRO. */
+    PatchUtils::ApplyPatches(&module_id, reinterpret_cast<u8 *>(map_address), nro_size);
+
     *out_module_id = module_id;
     *out_rx_size = header->text_size;
     *out_ro_size = header->ro_size;

stratosphere/ro/source/ro_registration.hpp

@@ -13,24 +13,24 @@
  * You should have received a copy of the GNU General Public License
  * along with this program.  If not, see <http://www.gnu.org/licenses/>.
  */
- 
+
 #pragma once
 #include <switch.h>
 
 #include <stratosphere.hpp>
 
 #include "ro_nrr.hpp"
+#include "ro_types.hpp"
 
 class Registration {
     public:
         /* NOTE: 2 ldr:ro, 2 ro:1. Nintendo only actually supports 2 total, but we'll be a little more generous. */
-        static constexpr size_t MaxSessions = 0x4; 
+        static constexpr size_t MaxSessions = 0x4;
         static constexpr size_t MaxNrrInfos = 0x40;
         static constexpr size_t MaxNroInfos = 0x40;
-        
+
         static constexpr u32 MagicNro0 = 0x304F524E;
     public:
-
         struct NroHeader {
             u32 entrypoint_insn;
             u32 mod_offset;
@@ -52,29 +52,6 @@ class Registration {
         };
         static_assert(sizeof(NroHeader) == 0x80, "NroHeader definition!");
 
-        struct ModuleId {
-            u8 build_id[0x20];
-        };
-        static_assert(sizeof(ModuleId) == sizeof(LoaderModuleInfo::build_id), "ModuleId definition!");
-        
-        struct Sha256Hash {
-            u8 hash[0x20];
-
-            bool operator==(const Sha256Hash &o) const {
-                return std::memcmp(this, &o, sizeof(*this)) == 0;
-            }
-            bool operator!=(const Sha256Hash &o) const {
-                return std::memcmp(this, &o, sizeof(*this)) != 0;
-            }
-            bool operator<(const Sha256Hash &o) const {
-                return std::memcmp(this, &o, sizeof(*this)) < 0;
-            }
-            bool operator>(const Sha256Hash &o) const {
-                return std::memcmp(this, &o, sizeof(*this)) > 0;
-            }
-        };
-        static_assert(sizeof(Sha256Hash) == sizeof(Sha256Hash::hash), "Sha256Hash definition!");
-
         struct NroInfo {
             u64 base_address;
             u64 nro_heap_address;
@@ -104,7 +81,7 @@ class Registration {
         static Result MapAndValidateNrr(NrrHeader **out_header, u64 *out_mapped_code_address, Handle process_handle, u64 title_id, u64 nrr_heap_address, u64 nrr_heap_size, RoModuleType expected_type, bool enforce_type);
         static Result UnmapNrr(Handle process_handle, const NrrHeader *header, u64 nrr_heap_address, u64 nrr_heap_size, u64 mapped_code_address);
         static bool IsNroHashPresent(RoProcessContext *context, const Sha256Hash *hash);
-        
+
         static Result MapNro(u64 *out_base_address, Handle process_handle, u64 nro_heap_address, u64 nro_heap_size, u64 bss_heap_address, u64 bss_heap_size);
         static Result ValidateNro(ModuleId *out_module_id, u64 *out_rx_size, u64 *out_ro_size, u64 *out_rw_size, RoProcessContext *context, u64 base_address, u64 nro_size, u64 bss_size);
         static Result SetNroPerms(Handle process_handle, u64 base_address, u64 rx_size, u64 ro_size, u64 rw_size);
@@ -115,7 +92,7 @@ class Registration {
 
         static Result RegisterProcess(RoProcessContext **out_context, Handle process_handle, u64 process_id);
         static void   UnregisterProcess(RoProcessContext *context);
-        
+
         static Result LoadNrr(RoProcessContext *context, u64 title_id, u64 nrr_address, u64 nrr_size, RoModuleType expected_type, bool enforce_type);
         static Result UnloadNrr(RoProcessContext *context, u64 nrr_address);
         static Result LoadNro(u64 *out_address, RoProcessContext *context, u64 nro_address, u64 nro_size, u64 bss_address, u64 bss_size);

stratosphere/ro/source/ro_types.hpp

@@ -0,0 +1,42 @@
+/*
+ * Copyright (c) 2018-2019 Atmosphère-NX
+ *
+ * This program is free software; you can redistribute it and/or modify it
+ * under the terms and conditions of the GNU General Public License,
+ * version 2, as published by the Free Software Foundation.
+ *
+ * This program is distributed in the hope it will be useful, but WITHOUT
+ * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
+ * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License for
+ * more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program.  If not, see <http://www.gnu.org/licenses/>.
+ */
+
+#pragma once
+#include <switch.h>
+#include <stratosphere.hpp>
+
+struct ModuleId {
+    u8 build_id[0x20];
+};
+static_assert(sizeof(ModuleId) == sizeof(LoaderModuleInfo::build_id), "ModuleId definition!");
+
+struct Sha256Hash {
+    u8 hash[0x20];
+
+    bool operator==(const Sha256Hash &o) const {
+        return std::memcmp(this, &o, sizeof(*this)) == 0;
+    }
+    bool operator!=(const Sha256Hash &o) const {
+        return std::memcmp(this, &o, sizeof(*this)) != 0;
+    }
+    bool operator<(const Sha256Hash &o) const {
+        return std::memcmp(this, &o, sizeof(*this)) < 0;
+    }
+    bool operator>(const Sha256Hash &o) const {
+        return std::memcmp(this, &o, sizeof(*this)) > 0;
+    }
+};
+static_assert(sizeof(Sha256Hash) == sizeof(Sha256Hash::hash), "Sha256Hash definition!");