File size: 11,800 Bytes
e93c9cc | 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 | # RE notes — EU4 1.37.5 loading tip / screen cycle mechanism
> Static-analysis findings on `eu4.exe` 1.37.5 (build 2024-10-03,
> SHA-256 `9ad3efe1af169f40ee577f9dae5debbc87af6fb8b5450fb345ebf110dc4d771a`).
> The goal of this file is to give the next maintainer enough breadcrumbs
> to skip the dead-ends and jump straight to the cycle function once
> Ghidra analysis finishes.
## Target binary
```
C:\Program Files (x86)\Steam\steamapps\common\Europa Universalis IV\eu4.exe
```
| Property | Value |
|------------------------|--------------------------------------------------------|
| Size | 38,462,504 bytes (36.7 MiB) |
| SHA-256 | `9ad3efe1af169f40ee577f9dae5debbc87af6fb8b5450fb345ebf110dc4d771a` |
| Version | `release_1.37.5` (rev `835bfdf8ca24c291a1b3f1b5bc72d47e7df1ae18`) |
| PE timestamp | 2024-10-03 17:58:17 |
| Format | PE32+ x86-64, 7 sections, no UPX |
| Linker | MSVC 14.29 (VS 2019 16.9–16.10) |
| ImageBase | `0x140000000` |
| PDB | none shipped (path string `eu4\eu4\outputdir_windows\eu4.pdb` only) |
| .text VMA / file | `0x140001000` / `0x00000400` size `0x1B64D78` |
| .rdata VMA / file | `0x141B66000` / `0x01B65200` size `0x44999A` |
| .data VMA / file | `0x141FB0000` / `0x01FAEC00` size `0x384400` |
## Loading-screen string table
A single string block in `.rdata` (file offset `0x1D62B4B` – `0x1D62B9C`)
contains every name the loading-screen code looks up by string:
| File offset | VMA | Bytes / purpose |
|-------------|----------------|----------------------------------------------------------------|
| `0x1D62B4B` | `0x141D62B4B` | `"load_screen2\0"` — sprite name `bg_load_screen2` (status bg) |
| `0x1D62B6C` | `0x141D62B6C` | `"tip\0"` — the loading-tip windowType |
| `0x1D62B70` | `0x141D62B70` | `"load_screen\0"` — the root load_screen windowType |
| `0x1D62B80` | `0x141D62B80` | `"LOADING_TIP_\0"` — localization key namespace (no xref; built dynamically via `format` + integer) |
| `0x1D62B88` | `0x141D62B88` | `"status\0"` — the loading-status windowType |
> None of `loading_tip`, `LOADING_TIP`, `loading_screen`, `LoadingScreen`,
> `getLocalization`, `getLocalisation`, `resolveKey`, `Timer`, `tick`,
> `interval`, `next_tip`, `setTextFromKey`, `set_loading_tip` appear
> as strings anywhere in the binary. The localization keys are built
> with `format("LOADING_TIP_{}", i)` at runtime, which is why
> `grep "LOADING_TIP_"` finds only the namespace literal and zero
> references.
## Loading-screen construction (`sub_141174F50`)
**Entry**: `0x141174F50` (image-base + offset, file offset = VMA −
`0x140000000` = `0x1D74F50`).
Called from two places, both inside the same TU:
- `0x1411749E9` — first call site
- `0x141174EE2` — second call site
The function:
1. Allocates a 32-byte string buffer (`call 0x1400950B0` is `operator new`).
2. Copies a 16-byte structure from `.rdata` into it, then a 2-byte and
1-byte tail.
3. Calls `vtable[0x120](rdi, &local)` (string-keyed registration or
`addChildByName`).
4. After allocation, sets `[rbx+0x100] = 1` (or `0`) based on
`[rip+0x12b6d79] + 0x28b` — almost certainly an
`is_loading_synchronous` / `is_replay` flag.
5. Calls `lea rdx, [rip+0xbedadd]` → `"load_screen"` and
`call [rax+0x98]` (a `findChildByName` virtual).
6. The branch at `0x14117509C`:
```
cmp [rbp+0x28], 1
je 0x1411750CA ; ironman/replay branch
cmp [rip+0x11caea6], 0 ; probably online check
jne 0x1411750CA
mov rdx, [rbx]
mov rcx, rbx
call [rdx+0x88] ; vtable[0x88]
```
The `vtable[0x88]` and `vtable[0x90]` are the two `setVisible` /
`setActive` overloads, depending on `[rbp+0x28] == 1`.
This is the **construction / activation** path, not the cycling path.
## Status-text updater (`sub_141174840`)
**Entry**: `0x141174840`.
1. `call 0x141172B20` — likely the `LoadingScreen::onEnter` initializer.
2. `lea rdx, [rip+0xbee32b]` → `"status"`; `call [rax+0xB8]` =
`findChildByName("status")`.
3. The found child at `[rax+0xC8]` is the `text` instantTextBox inside
`status`.
4. Then the function appends a fixed sequence of characters to the
textbox:
```
0x141174893: mov dl, 0x5C '\'
0x14117489D: mov dl, 0x2F '/'
0x1411748A7: mov dl, 0x3A ':'
0x1411748B1: mov dl, 0x2A '*'
0x1411748BB: mov dl, 0x3F '?'
0x1411748C5: mov dl, 0x3C '<'
0x1411748CF: mov dl, 0x3E '>'
0x1411748D9: mov dl, 0x7C '|'
```
These are the **classic ASCII spinner glyphs**. The function
re-renders them in sequence. This is the *status* progress
indicator, **not** the tip cycler.
5. Then `lea rdx, [rip+0xbee2a1]` → `0x141D62B94` (some other name,
the bytes are immediately after `"status\0"` in the string table)
and `call [rax+0x68]`. The function then tail-calls
`jmp [rax+0x8]` to a setter.
The status updater is driven by an outer loop — search for callers of
`0x141174840` to find the per-frame tick.
## Tip cycle function (NOT YET LOCATED)
What we know it must do:
1. Find the `"tip"` windowType child of the load_screen GUI
(`findChildByName("tip")` or via the child at offset 0xC8).
2. Increment an internal `Timer` member every frame.
3. When `elapsed >= interval`, pick a random `i` in `[0, 67)`, build
the key `"LOADING_TIP_" + i`, and call
`setText(localizedKey)` on the tip textbox.
4. Reset the timer to 0.
The `"tip\0"` C-string exists at VMA `0x141D62B6C` but **has zero xrefs
in the disassembly** as a literal. The function therefore either:
- Uses a hardcoded offset / index instead of a string lookup
(e.g. `getNthChild(1)` of the load_screen root), or
- Builds the `"tip"` name dynamically via `format` or string concat.
**Next step (with Ghidra decompiler):** decompile the call graph of
`sub_141174F50` (the load_screen setup) and look for the per-frame
update path. The cycling function is somewhere in that graph.
## Timer constants table
At VMA `0x141DC1750` (file offset `0x1DC0950`) is a 16-entry table of
`double` constants used by the engine for UI timers:
| VMA | Value | Likely use |
|------------------|-------------|---------------------------------------------|
| `0x141DC1750` | `4.0` | fast spinner tick |
| `0x141DC1758` | `5.0` | |
| `0x141DC1760` | `8.0000019` | (FP rounding artifact, paired with next) |
| `0x141DC1768` | `8.0` | **prime suspect for tip cycle interval** |
| `0x141DC1770` | `9.6` | (mid-game tick?) |
| `0x141DC1778` | `10.0` | slow spinner / pause |
| `0x141DC1780` | (garbage) | (denormal / uninitialised) |
| `0x141DC1788` | `15.0` | tooltip dwell |
| `0x141DC1790` | `20.0` | |
| `0x141DC1798` | `30.0` | |
| `0x141DC17A0` | `40.0` | |
| `0x141DC17A8` | (garbage) | |
| `0x141DC17B0` | `100.0` | |
| `0x141DC17B8` | `180.0` | |
| `0x141DC17C0` | `200.0` | |
The `8.0` value at `0x141DC1768` is referenced from 11 disassembly
sites. Most are *not* the tip cycler (verified: 0x14081D83A is part of
a `0x14081D...` per-frame update, 0x14182CC75 is a graphics normalize
function). The true cycle call site is one of the remaining xrefs and
will be identified by the call graph in the Ghidra decompile.
**Patch candidates** (most likely first):
- `0x1DC0968` (VMA `0x141DC1768`) — the `8.0` literal itself.
Patch: overwrite 8 bytes with the user's `tip_interval_seconds` as
a `double`. 8-byte write.
- Alternatively, if the cycle function takes the value via `movsd
xmm1, [rip+offset]` to the constant, we patch the `movsd` to load
from a writable .data cell the patcher initializes at runtime.
- A third option: NOP the `jbe` / `jge` after the elapsed-time
comparison in the cycle function to slow the cycle to "never".
## What remains to do (Ghidra pass)
1. Open `eu4.exe` in `C:\tools\ghidra_12.1.2_PUBLIC\ghidraRun.bat`.
2. Search → For Strings → `"load_screen"`, `"tip"`, `"status"`,
`"LOADING_TIP_"`.
3. For each, jump to the xref and decompile the containing function.
4. The tip cycler will be a function that:
- Reads `[rdi+0x30]` (vtable), looks up the `"tip"` child via
vtable[0xB8] (or a sibling lookup).
- Has a `Timer` member (look for `add`, `sub`, `cmp` with `8.0`
and a `jb`/`ja` that conditionally calls `setText`).
5. Record the VMA + file offset of the comparison constant, and
identify the byte pattern that uniquely matches across
`1.37.5.x` builds. The patcher will use this pattern for
`--rescan` after game updates.
## Ironman / achievement bypass (Phase 2 task, partially found)
The MD5-based integrity check is at VMA range **`0x1410F78B0` –
`0x1410F8666`**, with the hash init at **`0x1410F80B8`**
(`mov DWORD PTR [rbp+0xb0], 0x67452301` — the standard MD5 init
constant). The function:
1. Sets up the timer / state at `0x1410F8084` (`movsd xmm2, [rip+…]` →
`8.0`, passed as the third arg of a virtual call at
`0x1410F808E: call QWORD PTR [rax+0x10]`).
2. Computes the MD5 hash of the game state at `0x1410F84B0:
call 0x1410DD830`.
3. Uploads / records the hash via `0x1410F8573: call 0x1416554B0`
(with at least 6 string / data arguments, the most likely
"write to save header + sync to Paradox" call site).
4. Sets a global flag at `0x1410F85FA` (`mov DWORD PTR
[rip+0x1247877 + 0x747c], 1`) — almost certainly
`is_saving_ironman = true`.
5. Continues into the "save complete" path (call to
`0x1410F864E: call r8` for `vtable[0x10]`, which is the
`onSaveComplete` callback).
### Ironman patch candidates (to verify in next pass)
| VMA | Action |
|-----------------|------------------------------------------------------------------------|
| `0x1410F84B0` | 5-byte call `0x1410DD830` (MD5 compute). NOP it. |
| `0x1410F8573` | 5-byte call `0x1416554B0` (hash upload). NOP it. |
| `0x1410F85FA` | 10-byte `mov DWORD PTR [...+0x747c], 1`. Patch to `mov [...+0x747c], 0` to defeat "this is ironman" state. |
| `0x1410F80B8`–`0x1410F80C7` | 16-byte MD5 init constants. Wipe with NOPs. |
Any one of these patches alone is enough to disable a single link
in the chain; for full ironman-bypass, do all three. The
`--revert` path must restore the original bytes.
### Hash-upload destination string
The 6 string arguments to `0x1416554B0` at `0x1410F8500`–`0x1410F8573`
include:
- `0x141D5C438` — likely a Paradox account ID or session token
(used at `0x1410F84F3: lea rdx, [rip+0xc63f3e]`).
- A save-header key at `0x141D228B8` (used at `0x1410F799F`).
- A field at `0x141C4238C` (used at `0x1410F86E0` — to be confirmed).
These are good search anchors for the Ghidra xref pass.
|