content/blog/woce-2.md (view raw)
1+++
2title = "Writing our own Cheat Engine: Exact Value scanning"
3date = 2021-02-12
4updated = 2021-02-16
5[taxonomies]
6category = ["sw"]
7tags = ["windows", "rust", "hacking"]
8+++
9
10This is part 2 on the *Writing our own Cheat Engine* series:
11
12* [Part 1: Introduction](/blog/woce-1) (start here if you're new to the series!)
13* Part 2: Exact Value scanning
14
15In the introduction, we spent a good deal of time enumerating all running processes just so we could find out the pid we cared about. With the pid now in our hands, we can do pretty much anything to its corresponding process.
16
17It's now time to read the process' memory and write to it. If our process was a single-player game, this would enable us to do things like setting a very high value on the player's current health pool, making us invencible. This technique will often not work for multi-player games, because the server likely knows your true current health (the most you could probably do is make the client render an incorrect value). However, if the server is crappy and it trusts the client, then you're still free to mess around with your current health.
18
19Even if we don't want to write to the process' memory, reading is still very useful. Maybe you could enhance your experience by making a custom overlay that displays useful information, or something that makes noise if it detects the life is too low, or even simulating a keyboard event to automatically recover some mana when you're running low.
20
21Be warned about anti-cheat systems. Anything beyond a basic game is likely to have some protection measures in place, making the analysis more difficult (perhaps the values are scrambled in memory), or even pinging the server if it detects something fishy.
22
23**I am not responsible for any bans!** Use your brain before messing with online games, and don't ruin the fun for everyone else. If you get caught for cheating, I don't want to know about it.
24
25Now that all [script kiddies][script-kid] have left the room, let's proceed with the post.
26
27## Exact Value scanning
28
29<details open><summary>Cheat Engine Tutorial: Step 2</summary>
30
31> Now that you have opened the tutorial with Cheat Engine let's get on with the next step.
32>
33> You can see at the bottom of this window is the text Health: xxx. Each time you click 'Hit me' your health gets decreased.
34>
35> To get to the next step you have to find this value and change it to 1000
36>
37> To find the value there are different ways, but I'll tell you about the easiest, 'Exact Value': First make sure value type is set to at least 2-bytes or 4-bytes. 1-byte will also work, but you'll run into an easy to fix problem when you've found the address and want to change it. The 8-byte may perhaps works if the bytes after the address are 0, but I wouldn't take the bet. Single, double, and the other scans just don't work, because they store the value in a different way.
38>
39> When the value type is set correctly, make sure the scantype is set to 'Exact Value'. Then fill in the number your health is in the value box. And click 'First Scan'. After a while (if you have a extremely slow pc) the scan is done and the results are shown in the list on the left
40>
41> If you find more than 1 address and you don't know for sure which address it is, click 'Hit me', fill in the new health value into the value box, and click 'Next Scan'. Repeat this until you're sure you've found it. (that includes that there's only 1 address in the list.....)
42>
43> Now double click the address in the list on the left. This makes the address pop-up in the list at the bottom, showing you the current value. Double click the value, (or select it and press enter), and change the value to 1000.
44>
45> If everything went ok the next button should become enabled, and you're ready for the next step.
46>
47> Note: If you did anything wrong while scanning, click "New Scan" and repeat the scanning again. Also, try playing around with the value and click 'hit me'
48
49</details>
50
51## Our First Scan
52
53The Cheat Engine tutorial talks about "value types" and "scan types" like "exact value".
54
55The **value types** will help us narrow down *what* we're looking for. For example, the integer type `i32` is represented in memory as 32 bits, or 4 bytes. However, `f32` is *also* represented by 4 bytes, and so is `u32`. Or perhaps the 4 bytes represent RGBA values of a color! So any 4 bytes in memory can be interpreted in many ways, and it's up to us to decide which way we interpret the bytes in.
56
57When programming, numbers which are 32-bit wide are common, as they're a good (and fast) size to work with. Scanning for this type is often a good bet. For positive numbers, `i32` is represented the same as `u32` in memory, so even if the value turns out to not be signed, the scan is likely to work. Focusing on `i32` will save us from scanning for `f32` or even other types, like interpreting 8 bytes for `i64`, `f64`, or less bytes like `i16`.
58
59The **scan types** will help us narrow down *how* we're looking for a value. Scanning for an exact value means what you think it does: interpret all 4 bytes in the process' memory as our value type, and check if they exactly match our value. This will often yield a lot of candidates, but it will be enough to get us started. Variations of the exact scan include checking for all values below a threshold, above, in between, or even just… unknown.
60
61What's the point of scanning for unknown values if *everything* in memory is unknown? Sometimes you don't have a concrete value. Maybe your health pool is a bar and it nevers tell you how much health you actually have, just a visual indicator of your percentage left, even if the health is not stored as a percentage. As we will find later on, scanning for unknown values is more useful than it might appear at first.
62
63We can access the memory of our own program by guessing random pointers and trying to read from them. But Windows isolates the memory of each program, so no pointer we could ever guess will let us read from the memory of another process. Luckily for us, searching for "read process memory winapi" leads us to the [`ReadProcessMemory`][readmem] function. Spot on.
64
65```rust
66pub fn read_memory(&self, addr: usize, n: usize) -> io::Result<Vec<u8>> {
67 todo!()
68}
69```
70
71Much like trying to dereference a pointer pointing to released memory or even null, reading from an arbitrary address can fail for the same reasons (and more). We will want to signal this with `io::Result`. It's funny to note that, even though we're doing something that seems wildly unsafe (reading arbitrary memory, even if the other process is mutating it at the same time), the function is perfectly safe. If we cannot read something, it will return `Err`, but if it succeeds, it has taken a snapshot of the memory of the process, and the returned value will be correctly initialized.
72
73The function will be defined inside our `impl Process`, since it conveniently holds an open handle to the process in question. It takes `&self`, because we do not need to mutate anything in the `Process` instance. After adding the `memoryapi` feature to `Cargo.toml`, we can perform the call:
74
75```rust
76let mut buffer = Vec::<u8>::with_capacity(n);
77let mut read = 0;
78
79// SAFETY: the buffer points to valid memory, and the buffer size is correctly set.
80if unsafe {
81 winapi::um::memoryapi::ReadProcessMemory(
82 self.handle.as_ptr(),
83 addr as *const _,
84 buffer.as_mut_ptr().cast(),
85 buffer.capacity(),
86 &mut read,
87 )
88} == FALSE
89{
90 Err(io::Error::last_os_error())
91} else {
92 // SAFETY: the call succeeded and `read` contains the amount of bytes written.
93 unsafe { buffer.set_len(read as usize) };
94 Ok(buffer)
95}
96```
97
98Great! But the address space is somewhat large. 64 bits large. Eighteen quintillion, four hundred and forty-six quadrillion, seven hundred and forty-four trillion, seventy-three billion, seven hundred and nine million, five hundred and fifty-one thousand, six hundred and sixteen[^1] large. You gave up reading that, didn't you? Anyway, 18'446'744'073'709'551'616 is a *big* number.
99
100I am not willing to wait for the program to scan over so many values. I don't even have 16 [exbibytes] of RAM installed on my laptop yet[^2]! What's up with that?
101
102## Memory regions
103
104The program does not actually have all that memory allocated (surprise!). Random-guessing an address is extremely likely to point out to invalid memory. Reading from the start of the address space all the way to the end would not be any better. And we **need** to do better.
105
106We need to query for the memory regions allocated to the program. For this purpose we can use [`VirtualQueryEx`][vquery].
107
108> Retrieves information about a range of pages within the virtual address space of a specified process.
109
110We have enumerated things before, and this function is not all that different.
111
112```rust
113fn memory_regions(&self) -> io::Result<winapi::um::winnt::MEMORY_BASIC_INFORMATION> {
114 let mut info = MaybeUninit::uninit();
115
116 // SAFETY: the info structure points to valid memory.
117 let written = unsafe {
118 winapi::um::memoryapi::VirtualQueryEx(
119 self.handle.as_ptr(),
120 std::ptr::null(),
121 info.as_mut_ptr(),
122 mem::size_of::<winapi::um::winnt::MEMORY_BASIC_INFORMATION>(),
123 )
124 };
125 if written == 0 {
126 Err(io::Error::last_os_error())
127 } else {
128 // SAFETY: a non-zero amount was written to the structure
129 Ok(unsafe { info.assume_init() })
130 }
131}
132```
133
134We start with a base address of zero[^3] (`std::ptr::null()`), and ask the function to tell us what's in there. Let's try it out, with the `impl-debug` crate feature in `Cargo.toml`:
135
136```rust
137dbg!(process.memory_regions());
138```
139
140```
141>cargo run
142Compiling memo v0.1.0
143
144error[E0277]: `winapi::um::winnt::MEMORY_BASIC_INFORMATION` doesn't implement `std::fmt::Debug`
145 --> src\main.rs:185:5
146 |
147185 | dbg!(process.memory_regions());
148 | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ `winapi::um::winnt::MEMORY_BASIC_INFORMATION` cannot be formatted using `{:?}` because it doesn't implement `std::fmt::Debug`
149```
150
151That's annoying. It seems not everything has an `impl std::fmt::Debug`, and [you're supposed to send a PR][prdebug] if you want it to have debug, even if the `impl-debug` feature is set. I'm surprised they don't auto-generate all of this and have to rely on manually adding `Debug` as needed? Oh well, let's get rid of the feature and print it out ourselves:
152
153```
154eprintln!(
155 "Region:
156 BaseAddress: {:?}
157 AllocationBase: {:?}
158 AllocationProtect: {:?}
159 RegionSize: {:?}
160 State: {:?}
161 Protect: {:?}
162 Type: {:?}",
163 region.BaseAddress,
164 region.AllocationBase,
165 region.AllocationProtect,
166 region.RegionSize,
167 region.State,
168 region.Protect,
169 region.Type,
170);
171```
172
173Hopefully we don't need to do this often:
174
175```
176>cargo run
177 Compiling memo v0.1.0
178 Finished dev [unoptimized + debuginfo] target(s) in 0.60s
179 Running `target\debug\memo.exe`
180
181Region:
182 BaseAddress: 0x0
183 AllocationBase: 0x0
184 AllocationProtect: 0
185 RegionSize: 65536
186 State: 65536
187 Protect: 1
188 Type: 0
189```
190
191Awesome! There is a region at `null`, and the `AllocationProtect` of zero indicates that "the caller does not have access" when the region was created. However, `Protect` is `1`, and that is the *current* protection level. A value of one indicates [`PAGE_NOACCESS`][memprot]:
192
193> Disables all access to the committed region of pages. An attempt to read from, write to, or execute the committed region results in an access violation.
194
195Now that we know that the first region starts at 0 and has a size of 64 KiB, we can simply query for the page at `(current base + current size)` to fetch the next region. Essentially, we want to loop until it fails, after which we'll know there are no more pages[^4]:
196
197```rust
198pub fn memory_regions(&self) -> Vec<winapi::um::winnt::MEMORY_BASIC_INFORMATION> {
199 let mut base = 0;
200 let mut regions = Vec::new();
201 let mut info = MaybeUninit::uninit();
202
203 loop {
204 // SAFETY: the info structure points to valid memory.
205 let written = unsafe {
206 winapi::um::memoryapi::VirtualQueryEx(
207 self.handle.as_ptr(),
208 base as *const _,
209 info.as_mut_ptr(),
210 mem::size_of::<winapi::um::winnt::MEMORY_BASIC_INFORMATION>(),
211 )
212 };
213 if written == 0 {
214 break regions;
215 }
216 // SAFETY: a non-zero amount was written to the structure
217 let info = unsafe { info.assume_init() };
218 base = info.BaseAddress as usize + info.RegionSize;
219 regions.push(info);
220 }
221}
222```
223
224`RegionSize` is:
225
226> The size of the region beginning at the base address in which all pages have identical attributes, in bytes.
227
228…which also hints that the value we want is "base address", not the "allocation base". With these two values, we can essentially iterate over all the page ranges:
229
230```rust
231dbg!(process.memory_regions().len());
232```
233
234```
235>cargo run
236 Compiling memo v0.1.0
237 Finished dev [unoptimized + debuginfo] target(s) in 0.63s
238 Running `target\debug\memo.exe`
239
240[src\main.rs:189] process.memory_regions().len() = 367
241```
242
243That's a lot of pages!
244
245## Protection levels
246
247Let's try to narrow the amount of pages down. How many pages aren't `PAGE_NOACCESS`?
248
249```rust
250dbg!(process
251 .memory_regions()
252 .into_iter()
253 .filter(|p| p.Protect != winapi::um::winnt::PAGE_NOACCESS)
254 .count());
255```
256
257```
258295
259```
260
261Still a fair bit! Most likely, there are just a few interleaved `NOACCESS` pages, and the rest are allocated each with different protection levels. How much memory do we need to scan through?
262
263```rust
264dbg!(process
265 .memory_regions()
266 .into_iter()
267 .filter(|p| p.Protect != winapi::um::winnt::PAGE_NOACCESS)
268 .map(|p| p.RegionSize)
269 .sum::<usize>());
270```
271
272```
2734480434176
274```
275
276Wait, what? What do you mean over 4 GiB? The Task Manager claims that the Cheat Engine Tutorial is only using 2.1 MB worth of RAM! Perhaps we can narrow down the [protection levels][memprot] a bit more. If you look at the scan options in Cheat Engine, you will notice the "Memory Scan Options" groupbox. By default, it only scans for memory that is writable, and doesn't care if it's executable or not:
277
278
279```rust
280let mask = winnt::PAGE_EXECUTE_READWRITE
281 | winnt::PAGE_EXECUTE_WRITECOPY
282 | winnt::PAGE_READWRITE
283 | winnt::PAGE_WRITECOPY;
284
285dbg!(process
286 .memory_regions()
287 .into_iter()
288 .filter(|p| (p.Protect & mask) != 0)
289 .map(|p| p.RegionSize)
290 .sum::<usize>());
291```
292
293Each memory protection level has its own bit, so we can OR them all together to have a single mask. When ANDing this mask with the protection level, if any bit is set, it will be non-zero, meaning we want to keep this region.
294
295Don't ask me why there isn't a specific bit for "write", "read", "execute", and there are only bits for combinations. I guess this way Windows forbids certain combinations.
296
297```
2982580480
299```
300
301Hey, that's close to the value shown by the Task Manager! A handfull of megabytes is a lot more manageable than 4 entire gigabytes.
302
303## Actually running our First Scan
304
305Okay, we have all the memory regions from which the program can read, write, or execute. Now we also can read the memory in these regions:
306
307```rust
308let regions = process
309 .memory_regions()
310 .into_iter()
311 .filter(|p| (p.Protect & mask) != 0)
312 .collect::<Vec<_>>();
313
314println!("Scanning {} memory regions", regions.len());
315
316regions.into_iter().for_each(|region| {
317 match process.read_memory(region.BaseAddress as _, region.RegionSize) {
318 Ok(memory) => todo!(),
319 Err(err) => eprintln!(
320 "Failed to read {} bytes at {:?}: {}",
321 region.RegionSize, region.BaseAddress, err,
322 ),
323 }
324})
325```
326
327All that's left is for us to scan for a target value. To do this, we want to iterate over all the [`slice::windows`][slicewin] of size equal to the size of our scan type.
328
329```rust
330let target: i32 = ...;
331let target = target.to_ne_bytes();
332
333// -snip-
334
335// inside the Ok match, replacing the todo!() -- this is where the first scan happens
336Ok(memory) => memory
337 .windows(target.len())
338 .enumerate()
339 .for_each(|(offset, window)| {
340 if window == target {
341 println!(
342 "Found exact value at [{:?}+{:x}]",
343 region.BaseAddress, offset
344 );
345 }
346 })
347```
348
349We convert the 32-bit exact target value to its memory representation as a byte array in [native byte order][tone]. This way we can compare the target bytes with the window bytes. Another option is to interpret the window bytes as an `i32` with `from_be_bytes`, but `slice::windows` gives us slices of type `&[u8]`, and `from_be_bytes` wants an `[u8; 4]` array, so it's a bit more annoying to convert.
350
351This is enough to find the value in the process' memory!
352
353```
354Found exact value at [0x10000+aec]
355Failed to read 12288 bytes at 0x13f8000: Only part of a ReadProcessMemory or WriteProcessMemory request was completed. (os error 299)
356Found exact value at [0x14f0000+3188]
357Found exact value at [0x14f0000+ac74]
358...
359Found exact value at [0x10030e000+1816]
360Found exact value at [0x7ff8f7b93000+441a]
361...
362Found exact value at [0x7ff8fb381000+4023]
363```
364
365The tutorial starts out with health "100", which is what I scanned. Apparently, there are nearly a hundred of `100`-valued integers stored in the memory of the tutorial.
366
367Attentive readers will notice that some values are located at an offset modulo 4. In Cheat Engine, this is known as "Fast Scan", which is enabled by default with an alignment of 4. Most of the time, values are aligned in memory, and this alignment often corresponds with the size of the type itself. For 4-byte integers, it's common that they're 4-byte aligned.
368
369We can perform a fast scan ourselves with [`step_by`][stepby][^5]:
370
371```rust
372memory
373 .windows(target.len())
374 .enumerate()
375 .step_by(4)
376 .for_each(...)
377```
378
379As a bonus, over half the addresses are gone, so we have less results to worry about[^6].
380
381## Next Scan
382
383The first scan gave us way too many results. We have no way to tell which is the correct one, as they all have the same value. What we need to do is a *second* scan at the *locations we just found*. This way, we can get a second reading, and compare it against a new value. If it's the same, we're on good track, and if not, we can discard a location. Repeating this process lets us cut the hundreds of potential addresses to just a handful of them.
384
385For example, let's say we're scanning our current health of `100` in a game. This gives us over a hundred addresses that point to the value of `100`. If we go in-game and get hit[^7] by some enemy and get our health down to, say, `99` (we have a lot of defense), we can then read the memory at the hundred memory locations we found before. If this second reading is not `99`, we know the address does not actually point to our health pool and it just happened to also contain a `100` on the first scan. This address can be removed from the list of potential addresses pointing to our health.
386
387Let's do that:
388
389```rust
390// new vector to hold the locations, before getting into `memory.windows(target.len())`
391let mut locations = Vec::with_capacity(regions.len());
392
393// -snip-
394
395// updating the `println!("Found exact value...")` to store the location instead.
396if window == target {
397 locations.push(region.BaseAddress as usize + offset);
398}
399
400// -snip-
401
402// performing a second scan on the locations the first scan found.
403let target: i32 = ...;
404let target = target.to_ne_bytes();
405locations.retain(|addr| match process.read_memory(*addr, target.len()) {
406 Ok(memory) => memory == target,
407 Err(_) => false,
408});
409
410println!("Now have {} locations", locations.len());
411```
412
413We create a vector to store all the locations the first scan finds, and then retain those that match a second target value. You may have noticed that we perform a memory read, and thus a call to the Windows API, for every single address. With a hundred locations to read from, this is not a big deal, but oftentimes you will have tens of thousands of addresses. For the time being, we will not worry about this inefficiency, but we will get back to it once it matters:
414
415```
416Scanning 98 memory regions
417Which exact value to scan for?: 100
418Failed to read 12288 bytes at 0x13f8000: Only part of a ReadProcessMemory or WriteProcessMemory request was completed. (os error 299)
419...
420Found 49 locations
421Which exact value to scan for next?: 99
422Now have 1 locations
423```
424
425Sweet! In a real-world scenario, you will likely need to perform these additional scans a couple of times, and even then, there may be more than one value left no matter what.
426
427For good measure, we'll wrap our `retain` in a `while` loop[^8]:
428
429```rust
430while locations.len() != 1 {
431 let target: i32 = ...;
432 let target = target.to_ne_bytes();
433 locations.retain(...);
434}
435```
436
437## Modifying memory
438
439Now that we have very likely locations pointing to our current health in memory, all that's left is writing our new desired value to gain infinite health[^9]. Much like there's a call to `ReadProcessMemory`, there's a different one to [`WriteProcessMemory`][writemem]. Its usage is straightforward:
440
441```rust
442pub fn write_memory(&self, addr: usize, value: &[u8]) -> io::Result<usize> {
443 let mut written = 0;
444
445 // SAFETY: the input value buffer points to valid memory.
446 if unsafe {
447 winapi::um::memoryapi::WriteProcessMemory(
448 self.handle.as_ptr(),
449 addr as *mut _,
450 value.as_ptr().cast(),
451 value.len(),
452 &mut written,
453 )
454 } == FALSE
455 {
456 Err(io::Error::last_os_error())
457 } else {
458 Ok(written)
459 }
460}
461```
462
463Similar to how writing to a file can return short, writing to a memory location could also return short. Here we mimic the API for writing files and return the number of bytes written. The documentation indicates that we could actually ignore the amount written by passing `ptr::null_mut()` as the last parameter, but it does no harm to retrieve the written count as well.
464
465```rust
466let new_value: i32 = ...;
467locations
468 .into_iter()
469 .for_each(|addr| match process.write_memory(addr, &new_value) {
470 Ok(n) => eprintln!("Written {} bytes to [{:x}]", n, addr),
471 Err(e) => eprintln!("Failed to write to [{:x}]: {}", addr, e),
472 });
473```
474
475And just like that:
476
477```
478Now have 1 location(s)
479Enter new memory value: 1000
480Failed to write to [15d8b90]: Access is denied. (os error 5)
481```
482
483…oh noes. Oh yeah. The documentation, which I totally didn't forget to read, mentions:
484
485> The handle must have `PROCESS_VM_WRITE` and `PROCESS_VM_OPERATION` access to the process.
486
487We currently open our process with `PROCESS_QUERY_INFORMATION` and `PROCESS_VM_READ`, which is enough for reading, but not for writing. Let's adjust `OpenProcess` to accomodate for our new requirements:
488
489```rust
490winapi::um::processthreadsapi::OpenProcess(
491 winnt::PROCESS_QUERY_INFORMATION
492 | winnt::PROCESS_VM_READ
493 | winnt::PROCESS_VM_WRITE
494 | winnt::PROCESS_VM_OPERATION,
495 FALSE,
496 pid,
497)
498```
499
500Behold:
501
502```
503Now have 1 location(s)
504Enter new memory value: 1000
505Written 4 bytes to [15d8b90]
506```
507
508![Tutorial complete with memo][completion]
509
510Isn't that active *Next* button just beautiful?
511
512## Finale
513
514This post somehow ended up being longer than part one, but look at what we've achieved! We completed a step of the Cheat Engine Tutorial *without using Cheat Engine*. Just pure Rust. Figuring out how a program works and reimplementing it yourself is a great way to learn what it's doing behind the scenes. And now that this code is yours, you can extend it as much as you like, without being constrained by Cheat Engine's UI. You can automate it as much as you want.
515
516And we're not even done. The current tutorial has nine steps, and three additional graphical levels.
517
518In the next post, we'll tackle the third step of the tutorial: Unknown initial value. This will pose a challenge, because with just 2 MiB of memory, storing all the 4-byte aligned locations would require 524288 addresses (`usize`, 8 bytes). This adds up to twice as much memory as the original program (4 MiB), but that's not our main concern, having to perform over five hundred thousand API calls is!
519
520Remember that you can [obtain the code for this post][code] over at my GitHub. You can run `git checkout step2` after cloning the repository to get the right version of the code.
521
522### Footnotes
523
524[^1]: I did in fact use an online tool to spell it out for me.
525
526[^2]: 16 GiB is good enough for my needs. I don't think I'll ever upgrade to 16 EiB.
527
528[^3]: Every address we query should have a corresponding region, even if it's not allocated or we do not have access. This is why we can query for the memory address zero to get its corresponding region.
529
530[^4]: Another option is to [`GetSystemInfo`][getsysinfo] to determine the `lpMinimumApplicationAddress` and `lpMaximumApplicationAddress` and only work within bounds.
531
532[^5]: Memory regions are page-aligned, which is a large power of two. Our alignment of 4 is much lower than this, so we're guaranteed to start off at an aligned address.
533
534[^6]: If it turns out that the value was actually misaligned, we will miss it. You will notice this if, after going through the whole process, there are no results. It could mean that either the value type is wrong, or the value type is misaligned. In the worst case, the value is not stored directly but is rather computed with something like `maximum - stored`, or XORed with some magic value, or a myriad other things.
535
536[^7]: You could do this without getting hit, and just keep on repeating the scan for the same value over and over again. This does work, but the results are suboptimal, because there are also many other values that didn't change. Scanning for a changed value is a better option.
537
538[^8]: You could actually just go ahead and try to modify the memory at the hundred addresses you just found, although don't be surprised if the program starts to misbehave!
539
540[^9]: Okay, we cannot fit infinity in an `i32`. However, we can fit sufficiently large numbers. Like `1000`, which is enough to complete the tutorial.
541
542[script-kid]: https://www.urbandictionary.com/define.php?term=script%20kiddie
543[readmem]: https://docs.microsoft.com/en-us/windows/win32/api/memoryapi/nf-memoryapi-readprocessmemory
544[exbibytes]: https://en.wikipedia.org/wiki/Orders_of_magnitude_(data)
545[vquery]: https://docs.microsoft.com/en-us/windows/win32/api/memoryapi/nf-memoryapi-virtualqueryex
546[prdebug]: https://github.com/retep998/winapi-rs/issues/548#issuecomment-355278090
547[memprot]: https://docs.microsoft.com/en-us/windows/win32/memory/memory-protection-constants
548[getsysinfo]: https://docs.microsoft.com/en-us/windows/win32/api/sysinfoapi/nf-sysinfoapi-getsysteminfo
549[slicewin]: https://doc.rust-lang.org/stable/std/primitive.slice.html#method.windows
550[tone]: https://doc.rust-lang.org/stable/std/primitive.i32.html#method.to_ne_bytes
551[stepby]: https://doc.rust-lang.org/stable/std/iter/trait.Iterator.html#method.step_by
552[writemem]: https://docs.microsoft.com/en-us/windows/win32/api/memoryapi/nf-memoryapi-writeprocessmemory
553[completion]: https://user-images.githubusercontent.com/6297805/107829541-3f4f2d00-6d8a-11eb-87c4-e2f2d505afbc.png
554[code]: https://github.com/lonami/memo