Keyfork v0.3.3

CHANGELOG.md

@@ -1,3 +1,43 @@
+# Keyfork v0.3.3
+
+This release introduces a checksum verification mechanism for Remote Shard.
+
+### Changes in keyfork-prompt:
+
+```
+e7be91b keyfork-{shard,prompt}: add Yes/No prompt for verifying QR codes
+```
+
+### Changes in keyfork-shard:
+
+```
+e7be91b keyfork-{shard,prompt}: add Yes/No prompt for verifying QR codes
+739921d WIP: add checksum to shard
+```
+
+
+# Keyfork v0.3.2
+
+This is another bugfix release, allowing the derivation of Shard keys.
+
+
+### Changes in keyfork:
+
+```
+6ffcdc3 add derivation path for Shard keys
+```
+
+# Keyfork v0.3.1
+
+This is a bugfix release, resolving an issue with Keyfork Shard not having a
+exit condition for when a valid QR code was scanned.
+
+### Changes in keyfork-shard:
+
+```
+d0019a9 keyfork-shard: break loop when receiving valid QR code
+```
+
 # Keyfork v0.3.0
 
 The Wizard is Dead. Long Live the Mnemonic Generator.

Cargo.lock

@@ -1797,7 +1797,7 @@ dependencies = [
 
 [[package]]
 name = "keyfork"
-version = "0.3.0"
+version = "0.3.3"
 dependencies = [
  "base64",
  "card-backend-pcsc",
@@ -1944,7 +1944,7 @@ dependencies = [
 
 [[package]]
 name = "keyfork-prompt"
-version = "0.2.2"
+version = "0.2.3"
 dependencies = [
  "keyfork-bug",
  "keyfork-crossterm",
@@ -1967,7 +1967,7 @@ dependencies = [
 
 [[package]]
 name = "keyfork-shard"
-version = "0.3.2"
+version = "0.3.4"
 dependencies = [
  "aes-gcm",
  "anyhow",

Cargo.toml

@@ -35,17 +35,17 @@ keyforkd-models = { version = "0.2.0", path = "crates/daemon/keyforkd-models", r
 keyfork-derive-openpgp = { version = "0.1.2", path = "crates/derive/keyfork-derive-openpgp", registry = "distrust", default-features = false }
 keyfork-derive-path-data = { version = "0.1.1", path = "crates/derive/keyfork-derive-path-data", registry = "distrust", default-features = false }
 keyfork-derive-util = { version = "0.2.0", path = "crates/derive/keyfork-derive-util", registry = "distrust", default-features = false }
-keyfork-shard = { version = "0.3.0", path = "crates/keyfork-shard", registry = "distrust", default-features = false }
+keyfork-shard = { version = "0.3.4", path = "crates/keyfork-shard", registry = "distrust", default-features = false }
 keyfork-qrcode = { version = "0.1.1", path = "crates/qrcode/keyfork-qrcode", registry = "distrust", default-features = false }
 keyfork-zbar = { version = "0.1.0", path = "crates/qrcode/keyfork-zbar", registry = "distrust", default-features = false }
 keyfork-zbar-sys = { version = "0.1.0", path = "crates/qrcode/keyfork-zbar-sys", registry = "distrust", default-features = false }
 keyfork-bin = { version = "0.1.0", path = "crates/util/keyfork-bin", registry = "distrust", default-features = false }
-keyfork-bug = { version = "0.1.0", path = "crates/util/keyfork-bug", registry = "distrust", default-features = false }
+keyfork-bug = { version = "0.1.1", path = "crates/util/keyfork-bug", registry = "distrust", default-features = false }
 keyfork-crossterm = { version = "0.27.1", path = "crates/util/keyfork-crossterm", registry = "distrust", default-features = false }
 keyfork-entropy = { version = "0.1.1", path = "crates/util/keyfork-entropy", registry = "distrust", default-features = false }
 keyfork-frame = { version = "0.1.0", path = "crates/util/keyfork-frame", registry = "distrust", default-features = false }
 keyfork-mnemonic = { version = "0.4.0", path = "crates/util/keyfork-mnemonic", registry = "distrust", default-features = false }
-keyfork-prompt = { version = "0.2.0", path = "crates/util/keyfork-prompt", registry = "distrust", default-features = false }
+keyfork-prompt = { version = "0.2.3", path = "crates/util/keyfork-prompt", registry = "distrust", default-features = false }
 keyfork-slip10-test-data = { version = "0.1.0", path = "crates/util/keyfork-slip10-test-data", registry = "distrust", default-features = false }
 smex = { version = "0.1.0", path = "crates/util/smex", registry = "distrust", default-features = false }
 

crates/keyfork-shard/Cargo.toml

@@ -1,6 +1,6 @@
 [package]
 name = "keyfork-shard"
-version = "0.3.2"
+version = "0.3.4"
 edition = "2021"
 license = "AGPL-3.0-only"
 

crates/keyfork-shard/src/lib.rs

@@ -23,9 +23,9 @@ use keyfork_prompt::{
         mnemonic::{MnemonicSetValidator, MnemonicValidator, WordLength},
         Validator,
     },
-    Message as PromptMessage, PromptHandler,
+    Message as PromptMessage, PromptHandler, YesNo,
 };
-use sha2::Sha256;
+use sha2::{Digest, Sha256};
 use x25519_dalek::{EphemeralSecret, PublicKey};
 
 const PLAINTEXT_LENGTH: u8 = 32 // shard
@@ -59,6 +59,21 @@ impl std::fmt::Display for RetryScanMnemonic {
     }
 }
 
+fn calculate_checksum(slice: &[u8]) -> Vec<u8> {
+    // generate a verification checksum
+    // this checksum should be expensive to calculate
+    let mut payload = vec![];
+    for _ in 0..1_000_000 {
+        payload.extend(slice);
+        let mut hasher = Sha256::new();
+        hasher.update(&payload);
+        let result = hasher.finalize();
+        payload.clear();
+        payload.extend(result);
+    }
+    payload
+}
+
 #[cfg(feature = "openpgp")]
 pub mod openpgp;
 
@@ -273,14 +288,33 @@ pub trait Format {
                 .expect(bug!(POISONED_MUTEX))
                 .prompt_message(PromptMessage::Text(QRCODE_PROMPT.to_string()))?;
             loop {
-                if let Ok(Some(qrcode_content)) = keyfork_qrcode::scan_camera(
+                if let Ok(Some(qrcode_content)) =
-                    std::time::Duration::from_secs(*QRCODE_TIMEOUT),
+                    keyfork_qrcode::scan_camera(std::time::Duration::from_secs(*QRCODE_TIMEOUT), 0)
-                    0,
+                {
-                ) {
                     let decoded_data = BASE64_STANDARD
                         .decode(qrcode_content)
                         .expect(bug!("qrcode should contain base64 encoded data"));
-                    pubkey_data = Some(decoded_data.try_into().map_err(|_| InvalidData)?);
+                    let data: [u8; 32] = decoded_data.try_into().map_err(|_| InvalidData)?;
+                    let checksum = calculate_checksum(&data);
+                    let small_sum = &checksum[..8];
+                    let small_mnemonic = Mnemonic::from_raw_bytes(small_sum);
+
+                    let mut prompt = prompt.lock().expect(bug!(POISONED_MUTEX));
+                    let question =
+                        format!("Do these words match the expected words? {small_mnemonic}");
+                    let response = keyfork_prompt::prompt_choice(
+                        &mut **prompt,
+                        &question,
+                        &[YesNo::No, YesNo::Yes],
+                    )?;
+                    if response == YesNo::No {
+                        prompt.prompt_message(PromptMessage::Text(String::from(
+                            "Could not establish secure channel, exiting.",
+                        )))?;
+                        std::process::exit(1);
+                    }
+
+                    pubkey_data = Some(data);
                     break;
                 } else {
                     let mut prompt = prompt.lock().expect(bug!(POISONED_MUTEX));
@@ -535,15 +569,21 @@ pub fn remote_decrypt(w: &mut impl Write) -> Result<(), Box<dyn std::error::Erro
                 &BASE64_STANDARD.encode(qrcode_data),
                 ErrorCorrection::Highest,
             ) {
+                let checksum = calculate_checksum(key_mnemonic.as_bytes());
+                let small_sum = &checksum[..8];
+                let small_mnemonic = Mnemonic::from_raw_bytes(small_sum);
                 pm.prompt_message(PromptMessage::Text(format!(
                     concat!(
                         "QR code #{iter} will be displayed after this prompt. ",
                         "Send the QR code to the next shardholder. ",
-                        "Only the next shardholder should scan the QR code."
+                        "Only the next shardholder should scan the QR code. ",
                     ),
-                    iter = iter
+                    iter = iter,
                 )))?;
                 pm.prompt_message(PromptMessage::Data(qrcode))?;
+                pm.prompt_message(PromptMessage::Text(format!(
+                    "The following should be sent to verify the QR code: {small_mnemonic}"
+                )))?;
             }
         }
 
@@ -562,10 +602,9 @@ pub fn remote_decrypt(w: &mut impl Write) -> Result<(), Box<dyn std::error::Erro
         {
             pm.prompt_message(PromptMessage::Text(QRCODE_PROMPT.to_string()))?;
             loop {
-                if let Ok(Some(qrcode_content)) = keyfork_qrcode::scan_camera(
+                if let Ok(Some(qrcode_content)) =
-                    std::time::Duration::from_secs(*QRCODE_TIMEOUT),
+                    keyfork_qrcode::scan_camera(std::time::Duration::from_secs(*QRCODE_TIMEOUT), 0)
-                    0,
+                {
-                ) {
                     let decoded_data = BASE64_STANDARD
                         .decode(qrcode_content)
                         .expect(bug!("qrcode should contain base64 encoded data"));
@@ -578,6 +617,7 @@ pub fn remote_decrypt(w: &mut impl Write) -> Result<(), Box<dyn std::error::Erro
                     let _ =
                         pubkey_data.insert(decoded_data[..32].try_into().map_err(|_| InvalidData)?);
                     let _ = payload_data.insert(decoded_data[32..].to_vec());
+                    break;
                 } else {
                     let choice = keyfork_prompt::prompt_choice(
                         &mut *pm,

crates/keyfork/Cargo.toml

@@ -1,6 +1,6 @@
 [package]
 name = "keyfork"
-version = "0.3.0"
+version = "0.3.3"
 edition = "2021"
 license = "AGPL-3.0-only"
 
@@ -8,7 +8,7 @@ license = "AGPL-3.0-only"
 default = [
 	"completion",
 	"qrcode-decode-backend-rqrr",
- 	"sequoia-crypto-backend-nettle",
+	"sequoia-crypto-backend-nettle",
 ]
 
 completion = ["dep:clap_complete"]

crates/keyfork/src/cli/derive.rs

@@ -58,6 +58,9 @@ pub enum Path {
 
     /// The Disaster Recovery index.
     DisasterRecovery,
+
+    /// The Shard index.
+    Shard,
 }
 
 impl std::fmt::Display for Path {
@@ -71,6 +74,7 @@ impl Path {
         match self {
             Path::Default => "default",
             Path::DisasterRecovery => "disaster-recovery",
+            Path::Shard => "shard",
         }
     }
 
@@ -78,6 +82,7 @@ impl Path {
         match self {
             Self::Default => paths::OPENPGP.clone(),
             Self::DisasterRecovery => paths::OPENPGP_DISASTER_RECOVERY.clone(),
+            Self::Shard => paths::OPENPGP_SHARD.clone(),
         }
     }
 }

crates/util/keyfork-prompt/Cargo.toml

@@ -1,6 +1,6 @@
 [package]
 name = "keyfork-prompt"
-version = "0.2.2"
+version = "0.2.3"
 description = "Prompt management utilities for Keyfork"
 repository = "https://git.distrust.co/public/keyfork"
 edition = "2021"

crates/util/keyfork-prompt/src/lib.rs

@@ -83,6 +83,34 @@ impl<T: Choice> Choice for &T {
     }
 }
 
+/// A Yes/No Choice.
+#[derive(PartialEq, Eq, Clone, Copy)]
+pub enum YesNo {
+    /// Yes.
+    Yes,
+
+    /// No.
+    No,
+}
+
+impl std::fmt::Display for YesNo {
+    fn fmt(&self, f: &mut std::fmt::Formatter<'_>) -> std::fmt::Result {
+        match self {
+            YesNo::Yes => f.write_str("Yes"),
+            YesNo::No => f.write_str("No"),
+        }
+    }
+}
+
+impl Choice for YesNo {
+    fn identifier(&self) -> Option<char> {
+        match self {
+            YesNo::Yes => Some('y'),
+            YesNo::No => Some('n'),
+        }
+    }
+}
+
 #[doc(hidden)]
 pub type BoxResult = std::result::Result<(), Box<dyn std::error::Error>>;