1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
|
// Copyright 2014 Citra Emulator Project
// Licensed under GPLv2 or any later version
// Refer to the license.txt file included.
#include <algorithm>
#include <vector>
#include "common/logging/log.h"
#include "core/file_sys/archive_romfs.h"
#include "core/hle/kernel/process.h"
#include "core/hle/kernel/resource_limit.h"
#include "core/hle/service/fs/archive.h"
#include "core/loader/elf.h"
#include "core/loader/ncch.h"
#include "core/memory.h"
#include "3dsx.h"
namespace Loader {
/**
* File layout:
* - File header
* - Code, rodata and data relocation table headers
* - Code segment
* - Rodata segment
* - Loadable (non-BSS) part of the data segment
* - Code relocation table
* - Rodata relocation table
* - Data relocation table
*
* Memory layout before relocations are applied:
* [0..codeSegSize) -> code segment
* [codeSegSize..rodataSegSize) -> rodata segment
* [rodataSegSize..dataSegSize) -> data segment
*
* Memory layout after relocations are applied: well, however the loader sets it up :)
* The entrypoint is always the start of the code segment.
* The BSS section must be cleared manually by the application.
*/
enum THREEDSX_Error {
ERROR_NONE = 0,
ERROR_READ = 1,
ERROR_FILE = 2,
ERROR_ALLOC = 3
};
static const u32 RELOCBUFSIZE = 512;
// File header
#pragma pack(1)
struct THREEDSX_Header
{
u32 magic;
u16 header_size, reloc_hdr_size;
u32 format_ver;
u32 flags;
// Sizes of the code, rodata and data segments +
// size of the BSS section (uninitialized latter half of the data segment)
u32 code_seg_size, rodata_seg_size, data_seg_size, bss_size;
};
// Relocation header: all fields (even extra unknown fields) are guaranteed to be relocation counts.
struct THREEDSX_RelocHdr
{
// # of absolute relocations (that is, fix address to post-relocation memory layout)
u32 cross_segment_absolute;
// # of cross-segment relative relocations (that is, 32bit signed offsets that need to be patched)
u32 cross_segment_relative;
// more?
// Relocations are written in this order:
// - Absolute relocations
// - Relative relocations
};
// Relocation entry: from the current pointer, skip X words and patch Y words
struct THREEDSX_Reloc
{
u16 skip, patch;
};
#pragma pack()
struct THREEloadinfo
{
u8* seg_ptrs[3]; // code, rodata & data
u32 seg_addrs[3];
u32 seg_sizes[3];
};
static u32 TranslateAddr(u32 addr, const THREEloadinfo *loadinfo, u32* offsets)
{
if (addr < offsets[0])
return loadinfo->seg_addrs[0] + addr;
if (addr < offsets[1])
return loadinfo->seg_addrs[1] + addr - offsets[0];
return loadinfo->seg_addrs[2] + addr - offsets[1];
}
static THREEDSX_Error Load3DSXFile(FileUtil::IOFile& file, u32 base_addr)
{
if (!file.IsOpen())
return ERROR_FILE;
// Reset read pointer in case this file has been read before.
file.Seek(0, SEEK_SET);
THREEDSX_Header hdr;
if (file.ReadBytes(&hdr, sizeof(hdr)) != sizeof(hdr))
return ERROR_READ;
THREEloadinfo loadinfo;
//loadinfo segments must be a multiple of 0x1000
loadinfo.seg_sizes[0] = (hdr.code_seg_size + 0xFFF) &~0xFFF;
loadinfo.seg_sizes[1] = (hdr.rodata_seg_size + 0xFFF) &~0xFFF;
loadinfo.seg_sizes[2] = (hdr.data_seg_size + 0xFFF) &~0xFFF;
u32 offsets[2] = { loadinfo.seg_sizes[0], loadinfo.seg_sizes[0] + loadinfo.seg_sizes[1] };
u32 data_load_size = (hdr.data_seg_size - hdr.bss_size + 0xFFF) &~0xFFF;
u32 bss_load_size = loadinfo.seg_sizes[2] - data_load_size;
u32 n_reloc_tables = hdr.reloc_hdr_size / 4;
std::vector<u8> all_mem(loadinfo.seg_sizes[0] + loadinfo.seg_sizes[1] + loadinfo.seg_sizes[2] + 3 * n_reloc_tables);
loadinfo.seg_addrs[0] = base_addr;
loadinfo.seg_addrs[1] = loadinfo.seg_addrs[0] + loadinfo.seg_sizes[0];
loadinfo.seg_addrs[2] = loadinfo.seg_addrs[1] + loadinfo.seg_sizes[1];
loadinfo.seg_ptrs[0] = &all_mem[0];
loadinfo.seg_ptrs[1] = loadinfo.seg_ptrs[0] + loadinfo.seg_sizes[0];
loadinfo.seg_ptrs[2] = loadinfo.seg_ptrs[1] + loadinfo.seg_sizes[1];
// Skip header for future compatibility
file.Seek(hdr.header_size, SEEK_SET);
// Read the relocation headers
u32* relocs = (u32*)(loadinfo.seg_ptrs[2] + hdr.data_seg_size);
for (unsigned current_segment : {0, 1, 2}) {
size_t size = n_reloc_tables * 4;
if (file.ReadBytes(&relocs[current_segment * n_reloc_tables], size) != size)
return ERROR_READ;
}
// Read the segments
if (file.ReadBytes(loadinfo.seg_ptrs[0], hdr.code_seg_size) != hdr.code_seg_size)
return ERROR_READ;
if (file.ReadBytes(loadinfo.seg_ptrs[1], hdr.rodata_seg_size) != hdr.rodata_seg_size)
return ERROR_READ;
if (file.ReadBytes(loadinfo.seg_ptrs[2], hdr.data_seg_size - hdr.bss_size) != hdr.data_seg_size - hdr.bss_size)
return ERROR_READ;
// BSS clear
memset((char*)loadinfo.seg_ptrs[2] + hdr.data_seg_size - hdr.bss_size, 0, hdr.bss_size);
// Relocate the segments
for (unsigned current_segment : {0, 1, 2}) {
for (unsigned current_segment_reloc_table = 0; current_segment_reloc_table < n_reloc_tables; current_segment_reloc_table++) {
u32 n_relocs = relocs[current_segment * n_reloc_tables + current_segment_reloc_table];
if (current_segment_reloc_table >= 2) {
// We are not using this table - ignore it because we don't know what it dose
file.Seek(n_relocs*sizeof(THREEDSX_Reloc), SEEK_CUR);
continue;
}
static THREEDSX_Reloc reloc_table[RELOCBUFSIZE];
u32* pos = (u32*)loadinfo.seg_ptrs[current_segment];
const u32* end_pos = pos + (loadinfo.seg_sizes[current_segment] / 4);
while (n_relocs) {
u32 remaining = std::min(RELOCBUFSIZE, n_relocs);
n_relocs -= remaining;
if (file.ReadBytes(reloc_table, remaining * sizeof(THREEDSX_Reloc)) != remaining * sizeof(THREEDSX_Reloc))
return ERROR_READ;
for (unsigned current_inprogress = 0; current_inprogress < remaining && pos < end_pos; current_inprogress++) {
const auto& table = reloc_table[current_inprogress];
LOG_TRACE(Loader, "(t=%d,skip=%u,patch=%u)\n", current_segment_reloc_table,
(u32)table.skip, (u32)table.patch);
pos += table.skip;
s32 num_patches = table.patch;
while (0 < num_patches && pos < end_pos) {
u32 in_addr = (char*)pos - (char*)&all_mem[0];
u32 addr = TranslateAddr(*pos, &loadinfo, offsets);
LOG_TRACE(Loader, "Patching %08X <-- rel(%08X,%d) (%08X)\n",
base_addr + in_addr, addr, current_segment_reloc_table, *pos);
switch (current_segment_reloc_table) {
case 0:
*pos = (addr);
break;
case 1:
*pos = (addr - in_addr);
break;
default:
break; //this should never happen
}
pos++;
num_patches--;
}
}
}
}
}
// Write the data
memcpy(Memory::GetPointer(base_addr), &all_mem[0], loadinfo.seg_sizes[0] + loadinfo.seg_sizes[1] + loadinfo.seg_sizes[2]);
LOG_DEBUG(Loader, "CODE: %u pages\n", loadinfo.seg_sizes[0] / 0x1000);
LOG_DEBUG(Loader, "RODATA: %u pages\n", loadinfo.seg_sizes[1] / 0x1000);
LOG_DEBUG(Loader, "DATA: %u pages\n", data_load_size / 0x1000);
LOG_DEBUG(Loader, "BSS: %u pages\n", bss_load_size / 0x1000);
return ERROR_NONE;
}
FileType AppLoader_THREEDSX::IdentifyType(FileUtil::IOFile& file) {
u32 magic;
file.Seek(0, SEEK_SET);
if (1 != file.ReadArray<u32>(&magic, 1))
return FileType::Error;
if (MakeMagic('3', 'D', 'S', 'X') == magic)
return FileType::THREEDSX;
return FileType::Error;
}
ResultStatus AppLoader_THREEDSX::Load() {
if (is_loaded)
return ResultStatus::ErrorAlreadyLoaded;
if (!file->IsOpen())
return ResultStatus::Error;
Kernel::g_current_process = Kernel::Process::Create(filename, 0);
Kernel::g_current_process->svc_access_mask.set();
Kernel::g_current_process->address_mappings = default_address_mappings;
// Attach the default resource limit (APPLICATION) to the process
Kernel::g_current_process->resource_limit = Kernel::ResourceLimit::GetForCategory(Kernel::ResourceLimitCategory::APPLICATION);
Load3DSXFile(*file, Memory::PROCESS_IMAGE_VADDR);
Kernel::g_current_process->Run(Memory::PROCESS_IMAGE_VADDR, 48, Kernel::DEFAULT_STACK_SIZE);
is_loaded = true;
return ResultStatus::Success;
}
} // namespace Loader
|
