iOS Frida Konfigurasie

Reading time: 9 minutes

Installeer Frida

Stappe om Frida op 'n Jailbroken toestel te installeer:

1. Maak die Cydia/Sileo-app oop.
2. Navigeer na Bestuur -> Bronne -> Wysig -> Voeg by.
3. Voer "https://build.frida.re" in as die URL.
4. Gaan na die nuut bygevoegde Frida-bron.
5. Installeer die Frida-pakket.

As jy Corellium gebruik, sal jy die Frida-vrystelling van https://github.com/frida/frida/releases moet aflaai (frida-gadget-[yourversion]-ios-universal.dylib.gz) en uitpak en kopieer na die dylib-ligging wat Frida vra, bv.: /Users/[youruser]/.cache/frida/gadget-ios.dylib

Nadat dit geïnstalleer is, kan jy op jou rekenaar die opdrag frida-ls-devices gebruik en kyk of die toestel verskyn (jou rekenaar moet toegang daartoe hê).
Voer ook frida-ps -Uia uit om die lopende prosesse van die telefoon te kontroleer.

Frida sonder Jailbroken toestel & sonder om die app te patch

Kyk na hierdie blogpos oor hoe om Frida in nie-jailbroken toestelle te gebruik sonder om die app te patch: https://mrbypass.medium.com/unlocking-potential-exploring-frida-objection-on-non-jailbroken-devices-without-application-ed0367a84f07

Frida Kliënt Installasie

Installeer frida tools:

pip install frida-tools
pip install frida

Met die Frida-bediener geïnstalleer en die toestel wat loop en gekoppel is, kontroleer of die kliënt werk:

frida-ls-devices  # List devices
frida-ps -Uia     # Get running processes

Frida Trace

# Functions
## Trace all functions with the word "log" in their name
frida-trace -U <program> -i "*log*"
frida-trace -U <program> -i "*log*" | swift demangle # Demangle names

# Objective-C
## Trace all methods of all classes
frida-trace -U <program> -m "*[* *]"

## Trace all methods with the word "authentication" from classes that start with "NE"
frida-trace -U <program> -m "*[NE* *authentication*]"

# Plug-In
## To hook a plugin that is momentarely executed prepare Frida indicating the ID of the Plugin binary
frida-trace -U -W <if-plugin-bin> -m '*[* *]'

Kry alle klasse en metodes

• Outomatiese voltooiing: Voer net frida -U <program> uit

• Kry alle beskikbare klasse (filter op string)

// frida -U <program> -l /tmp/script.js

var filterClass = "filterstring"

if (ObjC.available) {
for (var className in ObjC.classes) {
if (ObjC.classes.hasOwnProperty(className)) {
if (!filterClass || className.includes(filterClass)) {
console.log(className)
}
}
}
} else {
console.log("Objective-C runtime is not available.")
}

• Kry alle metodes van 'n klas (filter op string)

// frida -U <program> -l /tmp/script.js

var specificClass = "YourClassName"
var filterMethod = "filtermethod"

if (ObjC.available) {
if (ObjC.classes.hasOwnProperty(specificClass)) {
var methods = ObjC.classes[specificClass].$ownMethods
for (var i = 0; i < methods.length; i++) {
if (!filterMethod || methods[i].includes(filterClass)) {
console.log(specificClass + ": " + methods[i])
}
}
} else {
console.log("Class not found.")
}
} else {
console.log("Objective-C runtime is not available.")
}

• Bel 'n funksie

// Find the address of the function to call
const func_addr = Module.findExportByName("<Prog Name>", "<Func Name>")
// Declare the function to call
const func = new NativeFunction(
func_addr,
"void",
["pointer", "pointer", "pointer"],
{}
)

var arg0 = null

// In this case to call this function we need to intercept a call to it to copy arg0
Interceptor.attach(wg_log_addr, {
onEnter: function (args) {
arg0 = new NativePointer(args[0])
},
})

// Wait untill a call to the func occurs
while (!arg0) {
Thread.sleep(1)
console.log("waiting for ptr")
}

var arg1 = Memory.allocUtf8String("arg1")
var txt = Memory.allocUtf8String("Some text for arg2")
wg_log(arg0, arg1, txt)

console.log("loaded")

Frida Fuzzing

Frida Stalker

From the docs: Stalker is Frida se kode opsporing enjin. Dit laat threads toe om gevolg te word, vang elke funksie, elke blok, selfs elke instruksie wat uitgevoer word.

Jy het 'n voorbeeld wat Frida Stalker implementeer in https://github.com/poxyran/misc/blob/master/frida-stalker-example.py

Dit is nog 'n voorbeeld om Frida Stalker aan te sluit elke keer as 'n funksie aangeroep word:

console.log("loading")
const wg_log_addr = Module.findExportByName("<Program>", "<function_name>")
const wg_log = new NativeFunction(
wg_log_addr,
"void",
["pointer", "pointer", "pointer"],
{}
)

Interceptor.attach(wg_log_addr, {
onEnter: function (args) {
console.log(`logging the following message: ${args[2].readCString()}`)

Stalker.follow({
events: {
// only collect coverage for newly encountered blocks
compile: true,
},
onReceive: function (events) {
const bbs = Stalker.parse(events, {
stringify: false,
annotate: false,
})
console.log(
"Stalker trace of write_msg_to_log: \n" +
bbs.flat().map(DebugSymbol.fromAddress).join("\n")
)
},
})
},
onLeave: function (retval) {
Stalker.unfollow()
Stalker.flush() // this is important to get all events
},
})

Fpicker

fpicker is 'n Frida-gebaseerde fuzzing suite wat 'n verskeidenheid fuzzing-modusse bied vir in-proses fuzzing, soos 'n AFL++-modus of 'n passiewe opsporingsmodus. Dit behoort op alle platforms wat deur Frida ondersteun word, te werk.

• Installeer fpicker & radamsa

# Get fpicker
git clone https://github.com/ttdennis/fpicker
cd fpicker

# Get Frida core devkit and prepare fpicker
wget https://github.com/frida/frida/releases/download/16.1.4/frida-core-devkit-16.1.4-[yourOS]-[yourarchitecture].tar.xz
# e.g. https://github.com/frida/frida/releases/download/16.1.4/frida-core-devkit-16.1.4-macos-arm64.tar.xz
tar -xf ./*tar.xz
cp libfrida-core.a libfrida-core-[yourOS].a #libfrida-core-macos.a

# Install fpicker
make fpicker-[yourOS] # fpicker-macos
# This generates ./fpicker

# Install radamsa (fuzzer generator)
brew install radamsa

• Bereid die FS voor:

# From inside fpicker clone
mkdir -p examples/wg-log # Where the fuzzing script will be
mkdir -p examples/wg-log/out # For code coverage and crashes
mkdir -p examples/wg-log/in # For starting inputs

# Create at least 1 input for the fuzzer
echo Hello World > examples/wg-log/in/0

• Fuzzer-skrip (examples/wg-log/myfuzzer.js):

// Import the fuzzer base class
import { Fuzzer } from "../../harness/fuzzer.js"

class WGLogFuzzer extends Fuzzer {
constructor() {
console.log("WGLogFuzzer constructor called")

// Get and declare the function we are going to fuzz
var wg_log_addr = Module.findExportByName(
"<Program name>",
"<func name to fuzz>"
)
var wg_log_func = new NativeFunction(
wg_log_addr,
"void",
["pointer", "pointer", "pointer"],
{}
)

// Initialize the object
super("<Program nane>", wg_log_addr, wg_log_func)
this.wg_log_addr = wg_log_addr // We cannot use "this" before calling "super"

console.log("WGLogFuzzer in the middle")

// Prepare the second argument to pass to the fuzz function
this.tag = Memory.allocUtf8String("arg2")

// Get the first argument we need to pass from a call to the functino we want to fuzz
var wg_log_global_ptr = null
console.log(this.wg_log_addr)
Interceptor.attach(this.wg_log_addr, {
onEnter: function (args) {
console.log("Entering in the function to get the first argument")
wg_log_global_ptr = new NativePointer(args[0])
},
})

while (!wg_log_global_ptr) {
Thread.sleep(1)
}
this.wg_log_global_ptr = wg_log_global_ptr
console.log("WGLogFuzzer prepare ended")
}

// This function is called by the fuzzer with the first argument being a pointer into memory
// where the payload is stored and the second the length of the input.
fuzz(payload, len) {
// Get a pointer to payload being a valid C string (with a null byte at the end)
var payload_cstring = payload.readCString(len)
this.payload = Memory.allocUtf8String(payload_cstring)

// Debug and fuzz
this.debug_log(this.payload, len)
// Pass the 2 first arguments we know the function needs and finally the payload to fuzz
this.target_function(this.wg_log_global_ptr, this.tag, this.payload)
}
}

const f = new WGLogFuzzer()
rpc.exports.fuzzer = f

• Compile die fuzzer:

# From inside fpicker clone
## Compile from "myfuzzer.js" to "harness.js"
frida-compile examples/wg-log/myfuzzer.js -o harness.js

• Roep fuzzer fpicker aan met radamsa:

# Indicate fpicker to fuzz a program with the harness.js script and which folders to use
fpicker -v --fuzzer-mode active -e attach -p <Program to fuzz> -D usb -o examples/wg-log/out/ -i examples/wg-log/in/ -f harness.js --standalone-mutator cmd --mutator-command "radamsa"
# You can find code coverage and crashes in examples/wg-log/out/

Logs & Crashes

Jy kan die macOS konsole of die log cli nagaan om macOS logs te kontroleer.
Jy kan ook die logs van iOS nagaan met idevicesyslog.
Sommige logs sal inligting weglat deur <private> by te voeg. Om al die inligting te wys, moet jy 'n profiel van https://developer.apple.com/bug-reporting/profiles-and-logs/ installeer om daardie private inligting te aktiveer.

As jy nie weet wat om te doen nie:

vim /Library/Preferences/Logging/com.apple.system.logging.plist
<?xml version="1.0" encoding="UTF-8"?>
<!DOCTYPE plist PUBLIC "-//Apple//DTD PLIST 1.0//EN" "http://www.apple.com/DTDs/PropertyList-1.0.dtd">
<plist version="1.0">
<dict>
<key>Enable-Private-Data</key>
<true/>
</dict>
</plist>

killall -9 logd

Jy kan die crashes nagaan in:

• iOS
• Instellings → Privaatheid → Analise & Verbeterings → Analise Data
• /private/var/mobile/Library/Logs/CrashReporter/
• macOS:
• /Library/Logs/DiagnosticReports/
• ~/Library/Logs/DiagnosticReports

Frida Android Tutorials

Frida Tutorial

References

• https://www.briskinfosec.com/blogs/blogsdetail/Getting-Started-with-Frida