dns.mitm: support % in hosts file as stand-in for environment identifier

libraries/libstratosphere/include/stratosphere.hpp

@@ -61,6 +61,7 @@
 #include <stratosphere/ncm.hpp>
 #include <stratosphere/nim.hpp>
 #include <stratosphere/ns.hpp>
+#include <stratosphere/nsd.hpp>
 #include <stratosphere/patcher.hpp>
 #include <stratosphere/pcv.hpp>
 #include <stratosphere/pgl.hpp>

libraries/libstratosphere/include/stratosphere/nsd.hpp

@@ -0,0 +1,18 @@
+/*
+ * Copyright (c) 2018-2020 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 <stratosphere/nsd/nsd_types.hpp>
+#include <stratosphere/nsd/impl/device/nsd_device.hpp>

libraries/libstratosphere/include/stratosphere/nsd/impl/device/nsd_device.hpp

@@ -0,0 +1,24 @@
+/*
+ * Copyright (c) 2018-2020 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 <vapours.hpp>
+#include <stratosphere/nsd/nsd_types.hpp>
+
+namespace ams::nsd::impl::device {
+
+    const EnvironmentIdentifier &GetEnvironmentIdentifierFromSettings();
+
+}

libraries/libstratosphere/include/stratosphere/nsd/nsd_types.hpp

@@ -0,0 +1,37 @@
+/*
+ * Copyright (c) 2018-2020 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 <vapours.hpp>
+
+namespace ams::nsd {
+
+    struct EnvironmentIdentifier {
+        static constexpr size_t Size = 8;
+        char value[Size];
+
+        constexpr friend bool operator==(const EnvironmentIdentifier &lhs, const EnvironmentIdentifier &rhs) {
+            return util::Strncmp(lhs.value, rhs.value, Size) == 0;
+        }
+
+        constexpr friend bool operator!=(const EnvironmentIdentifier &lhs, const EnvironmentIdentifier &rhs) {
+            return !(lhs == rhs);
+        }
+    };
+
+    constexpr inline const EnvironmentIdentifier EnvironmentIdentifierOfProductDevice    = {"lp1"};
+    constexpr inline const EnvironmentIdentifier EnvironmentIdentifierOfNotProductDevice = {"dd1"};
+
+}

libraries/libstratosphere/source/nsd/impl/device/nsd_device.cpp

@@ -0,0 +1,49 @@
+/*
+ * Copyright (c) 2018-2020 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 <stratosphere.hpp>
+
+namespace ams::nsd::impl::device {
+
+    namespace {
+
+        constexpr const char SettingsName[] = "nsd";
+        constexpr const char SettingsKey[]  = "environment_identifier";
+
+        constinit os::SdkMutex g_environment_identifier_lock;
+        constinit EnvironmentIdentifier g_environment_identifier = {};
+        constinit bool g_determined_environment_identifier = false;
+
+    }
+
+    const EnvironmentIdentifier &GetEnvironmentIdentifierFromSettings() {
+        std::scoped_lock lk(g_environment_identifier_lock);
+
+        if (!g_determined_environment_identifier) {
+            /* Check size. */
+            AMS_ABORT_UNLESS(settings::fwdbg::GetSettingsItemValueSize(SettingsName, SettingsKey) != 0);
+
+            /* Get value. */
+            const size_t size = settings::fwdbg::GetSettingsItemValue(g_environment_identifier.value, EnvironmentIdentifier::Size, SettingsName, SettingsKey);
+            AMS_ABORT_UNLESS(size < EnvironmentIdentifier::Size);
+            AMS_ABORT_UNLESS(g_environment_identifier == EnvironmentIdentifierOfProductDevice || g_environment_identifier == EnvironmentIdentifierOfNotProductDevice);
+
+            g_determined_environment_identifier = true;
+        }
+
+        return g_environment_identifier;
+    }
+
+}

libraries/libvapours/include/vapours/util/util_string_util.hpp

@@ -31,7 +31,7 @@ namespace ams::util {
     }
 
     template<typename T>
-    int Strncmp(const T *lhs, const T *rhs, int count) {
+    constexpr int Strncmp(const T *lhs, const T *rhs, int count) {
         AMS_ASSERT(lhs != nullptr);
         AMS_ASSERT(rhs != nullptr);
         AMS_ABORT_UNLESS(count >= 0);
@@ -50,7 +50,7 @@ namespace ams::util {
     }
 
     template<typename T>
-    int Strnicmp(const T *lhs, const T *rhs, int count) {
+    constexpr int Strnicmp(const T *lhs, const T *rhs, int count) {
         AMS_ASSERT(lhs != nullptr);
         AMS_ASSERT(rhs != nullptr);
         AMS_ABORT_UNLESS(count >= 0);

stratosphere/ams_mitm/source/dns_mitm/dnsmitm_host_redirection.cpp

@@ -66,10 +66,7 @@ namespace ams::mitm::socket::resolver {
 
         constexpr const char DefaultHostsFile[] =
             "# Nintendo telemetry servers\n"
-            "127.0.0.1 receive-*.*.srv.nintendo.net\n";
+            "127.0.0.1 receive-%.dg.srv.nintendo.net receive-%.er.srv.nintendo.net\n";
-
-        static_assert(wildcardcmp("receive-*.*.srv.nintendo.net", "receive-lp1.dg.srv.nintendo.net") == 1);
-        static_assert(wildcardcmp("receive-*.*.srv.nintendo.net", "receive-lp1.er.srv.nintendo.net") == 1);
 
         constinit os::SdkMutex g_redirection_lock;
         std::unordered_map<std::string, ams::socket::InAddrT> g_redirection_map;
@@ -77,6 +74,11 @@ namespace ams::mitm::socket::resolver {
         constinit char g_specific_emummc_hosts_path[0x40] = {};
 
         void ParseHostsFile(const char *file_data) {
+            /* Get the environment identifier from settings. */
+            const auto env     = ams::nsd::impl::device::GetEnvironmentIdentifierFromSettings();
+            const auto env_len = std::strlen(env.value);
+
+            /* Parse the file. */
             enum class State {
                 IgnoredLine,
                 BeginLine,
@@ -189,8 +191,13 @@ namespace ams::mitm::socket::resolver {
                         if (c == '\n') {
                             state = State::BeginLine;
                         } else if (c != ' ' && c != '\r' && c != '\t') {
-                            current_hostname[0] = c;
+                            if (c == '%') {
-                            work = 1;
+                                std::memcpy(current_hostname, env.value, env_len);
+                                work = env_len;
+                            } else {
+                                current_hostname[0] = c;
+                                work = 1;
+                            }
                             state = State::HostName;
                         }
                         break;
@@ -207,6 +214,10 @@ namespace ams::mitm::socket::resolver {
                             } else {
                                 state = State::WhiteSpace;
                             }
+                        } else if (c == '%') {
+                            AMS_ABORT_UNLESS(work < sizeof(current_hostname) - env_len);
+                            std::memcpy(current_hostname + work, env.value, env_len);
+                            work += env_len;
                         } else {
                             AMS_ABORT_UNLESS(work < sizeof(current_hostname) - 1);
                             current_hostname[work++] = c;