git subrepo clone https://github.com/Atmosphere-NX/Atmosphere-libs libraries

subrepo:
  subdir:   "libraries"
  merged:   "07af583b"
upstream:
  origin:   "https://github.com/Atmosphere-NX/Atmosphere-libs"
  branch:   "master"
  commit:   "07af583b"
git-subrepo:
  version:  "0.4.0"
  origin:   "https://github.com/ingydotnet/git-subrepo"
  commit:   "5d6aba9"

libraries/libstratosphere/source/map/map_api.cpp

@@ -0,0 +1,236 @@
+/*
+ * 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 <stratosphere.hpp>
+
+namespace ams::map {
+
+    namespace {
+
+        /* Convenience defines. */
+        constexpr size_t GuardRegionSize = 0x4000;
+        constexpr size_t LocateRetryCount = 0x200;
+
+        /* Deprecated/Modern implementations. */
+        Result LocateMappableSpaceDeprecated(uintptr_t *out_address, size_t size) {
+            MemoryInfo mem_info = {};
+            u32 page_info = 0;
+            uintptr_t cur_base = 0;
+
+            AddressSpaceInfo address_space;
+            R_TRY(GetProcessAddressSpaceInfo(&address_space, dd::GetCurrentProcessHandle()));
+            cur_base = address_space.aslr_base;
+
+            do {
+                R_TRY(svcQueryMemory(&mem_info, &page_info, cur_base));
+
+                if (mem_info.type == MemType_Unmapped && mem_info.addr - cur_base + mem_info.size >= size) {
+                    *out_address = cur_base;
+                    return ResultSuccess();
+                }
+
+                const uintptr_t mem_end = mem_info.addr + mem_info.size;
+                if (mem_info.type == MemType_Reserved || mem_end < cur_base || (mem_end >> 31)) {
+                    return svc::ResultOutOfMemory();
+                }
+
+                cur_base = mem_end;
+            } while (true);
+        }
+
+        Result LocateMappableSpaceModern(uintptr_t *out_address, size_t size) {
+            MemoryInfo mem_info = {};
+            u32 page_info = 0;
+            uintptr_t cur_base = 0, cur_end = 0;
+
+            AddressSpaceInfo address_space;
+            R_TRY(GetProcessAddressSpaceInfo(&address_space, dd::GetCurrentProcessHandle()));
+            cur_base = address_space.aslr_base;
+            cur_end = cur_base + size;
+
+            if (cur_end <= cur_base) {
+                return svc::ResultOutOfMemory();
+            }
+
+            while (true) {
+                if (address_space.heap_size && (address_space.heap_base <= cur_end - 1 && cur_base <= address_space.heap_end - 1)) {
+                    /* If we overlap the heap region, go to the end of the heap region. */
+                    if (cur_base == address_space.heap_end) {
+                        return svc::ResultOutOfMemory();
+                    }
+                    cur_base = address_space.heap_end;
+                } else if (address_space.alias_size && (address_space.alias_base <= cur_end - 1 && cur_base <= address_space.alias_end - 1)) {
+                    /* If we overlap the alias region, go to the end of the alias region. */
+                    if (cur_base == address_space.alias_end) {
+                        return svc::ResultOutOfMemory();
+                    }
+                    cur_base = address_space.alias_end;
+                } else {
+                    R_ASSERT(svcQueryMemory(&mem_info, &page_info, cur_base));
+                    if (mem_info.type == 0 && mem_info.addr - cur_base + mem_info.size >= size) {
+                        *out_address = cur_base;
+                        return ResultSuccess();
+                    }
+                    if (mem_info.addr + mem_info.size <= cur_base) {
+                        return svc::ResultOutOfMemory();
+                    }
+                    cur_base = mem_info.addr + mem_info.size;
+                    if (cur_base >= address_space.aslr_end) {
+                        return svc::ResultOutOfMemory();
+                    }
+                }
+                cur_end = cur_base + size;
+                if (cur_base + size <= cur_base) {
+                    return svc::ResultOutOfMemory();
+                }
+            }
+        }
+
+        Result MapCodeMemoryInProcessDeprecated(MappedCodeMemory &out_mcm, Handle process_handle, uintptr_t base_address, size_t size) {
+            AddressSpaceInfo address_space;
+            R_TRY(GetProcessAddressSpaceInfo(&address_space, process_handle));
+
+            if (size > address_space.aslr_size) {
+                return ro::ResultOutOfAddressSpace();
+            }
+
+            uintptr_t try_address;
+            for (unsigned int i = 0; i < LocateRetryCount; i++) {
+                try_address = address_space.aslr_base + (rnd::GenerateRandomU64(static_cast<u64>(address_space.aslr_size - size) >> 12) << 12);
+
+                MappedCodeMemory tmp_mcm(process_handle, try_address, base_address, size);
+                R_TRY_CATCH(tmp_mcm.GetResult()) {
+                    R_CATCH(svc::ResultInvalidCurrentMemoryState) {
+                        continue;
+                    }
+                } R_END_TRY_CATCH;
+
+                if (!CanAddGuardRegionsInProcess(process_handle, try_address, size)) {
+                    continue;
+                }
+
+                /* We're done searching. */
+                out_mcm = std::move(tmp_mcm);
+                return ResultSuccess();
+            }
+
+            return ro::ResultOutOfAddressSpace();
+        }
+
+        Result MapCodeMemoryInProcessModern(MappedCodeMemory &out_mcm, Handle process_handle, uintptr_t base_address, size_t size) {
+            AddressSpaceInfo address_space;
+            R_TRY(GetProcessAddressSpaceInfo(&address_space, process_handle));
+
+            if (size > address_space.aslr_size) {
+                return ro::ResultOutOfAddressSpace();
+            }
+
+            uintptr_t try_address;
+            for (unsigned int i = 0; i < LocateRetryCount; i++) {
+                while (true) {
+                    try_address = address_space.aslr_base + (rnd::GenerateRandomU64(static_cast<u64>(address_space.aslr_size - size) >> 12) << 12);
+                    if (address_space.heap_size && (address_space.heap_base <= try_address + size - 1 && try_address <= address_space.heap_end - 1)) {
+                        continue;
+                    }
+                    if (address_space.alias_size && (address_space.alias_base <= try_address + size - 1 && try_address <= address_space.alias_end - 1)) {
+                        continue;
+                    }
+                    break;
+                }
+
+                MappedCodeMemory tmp_mcm(process_handle, try_address, base_address, size);
+                R_TRY_CATCH(tmp_mcm.GetResult()) {
+                    R_CATCH(svc::ResultInvalidCurrentMemoryState) {
+                        continue;
+                    }
+                } R_END_TRY_CATCH;
+
+                if (!CanAddGuardRegionsInProcess(process_handle, try_address, size)) {
+                    continue;
+                }
+
+                /* We're done searching. */
+                out_mcm = std::move(tmp_mcm);
+                return ResultSuccess();
+            }
+
+            return ro::ResultOutOfAddressSpace();
+        }
+
+    }
+
+    /* Public API. */
+    Result GetProcessAddressSpaceInfo(AddressSpaceInfo *out, Handle process_h) {
+        /* Clear output. */
+        std::memset(out, 0, sizeof(*out));
+
+        /* Retrieve info from kernel. */
+        R_TRY(svcGetInfo(&out->heap_base,  InfoType_HeapRegionAddress, process_h, 0));
+        R_TRY(svcGetInfo(&out->heap_size,  InfoType_HeapRegionSize, process_h, 0));
+        R_TRY(svcGetInfo(&out->alias_base, InfoType_AliasRegionAddress, process_h, 0));
+        R_TRY(svcGetInfo(&out->alias_size, InfoType_AliasRegionSize, process_h, 0));
+        if (hos::GetVersion() >= hos::Version_200) {
+            R_TRY(svcGetInfo(&out->aslr_base, InfoType_AslrRegionAddress, process_h, 0));
+            R_TRY(svcGetInfo(&out->aslr_size, InfoType_AslrRegionSize, process_h, 0));
+        } else {
+            /* Auto-detect 32-bit vs 64-bit. */
+            if (out->heap_base < AslrBase64BitDeprecated || out->alias_base < AslrBase64BitDeprecated) {
+                out->aslr_base = AslrBase32Bit;
+                out->aslr_size = AslrSize32Bit;
+            } else {
+                out->aslr_base = AslrBase64BitDeprecated;
+                out->aslr_size = AslrSize64BitDeprecated;
+            }
+        }
+
+        out->heap_end = out->heap_base + out->heap_size;
+        out->alias_end = out->alias_base + out->alias_size;
+        out->aslr_end = out->aslr_base + out->aslr_size;
+        return ResultSuccess();
+    }
+
+    Result LocateMappableSpace(uintptr_t *out_address, size_t size) {
+        if (hos::GetVersion() >= hos::Version_200) {
+            return LocateMappableSpaceModern(out_address, size);
+        } else {
+            return LocateMappableSpaceDeprecated(out_address, size);
+        }
+    }
+
+    Result MapCodeMemoryInProcess(MappedCodeMemory &out_mcm, Handle process_handle, uintptr_t base_address, size_t size) {
+        if (hos::GetVersion() >= hos::Version_200) {
+            return MapCodeMemoryInProcessModern(out_mcm, process_handle, base_address, size);
+        } else {
+            return MapCodeMemoryInProcessDeprecated(out_mcm, process_handle, base_address, size);
+        }
+    }
+
+    bool CanAddGuardRegionsInProcess(Handle process_handle, uintptr_t address, size_t size) {
+        MemoryInfo mem_info;
+        u32 page_info;
+
+        /* Nintendo doesn't validate SVC return values at all. */
+        /* TODO: Should we allow these to fail? */
+        R_ASSERT(svcQueryProcessMemory(&mem_info, &page_info, process_handle, address - 1));
+        if (mem_info.type == MemType_Unmapped && address - GuardRegionSize >= mem_info.addr) {
+            R_ASSERT(svcQueryProcessMemory(&mem_info, &page_info, process_handle, address + size));
+            return mem_info.type == MemType_Unmapped && address + size + GuardRegionSize <= mem_info.addr + mem_info.size;
+        }
+
+        return false;
+    }
+
+}