hopr_internal_types/
tickets.rs

1use std::{
2    cmp::Ordering,
3    fmt::{Display, Formatter},
4};
5
6use hex_literal::hex;
7use hopr_crypto_types::prelude::*;
8use hopr_primitive_types::prelude::*;
9use tracing::{debug, error};
10
11use crate::{
12    errors,
13    errors::CoreTypesError,
14    prelude::{CoreTypesError::InvalidInputData, generate_channel_id},
15};
16
17/// Size-optimized encoding of the ticket, used for both,
18/// network transfer and in the smart contract.
19const ENCODED_TICKET_LENGTH: usize = 64;
20
21/// Custom float to integer encoding used in the integer-only
22/// Ethereum Virtual Machine (EVM). Chosen to be easily
23/// convertible to IEEE754 double-precision and vice versa
24const ENCODED_WIN_PROB_LENGTH: usize = 7;
25
26/// Define the selector for the redeemTicketCall to avoid importing
27/// the entire hopr-bindings crate for one single constant.
28/// This value should be updated with the function interface changes.
29pub const REDEEM_CALL_SELECTOR: [u8; 4] = [252, 183, 121, 111];
30
31/// Winning probability encoded in 7-byte representation
32pub type EncodedWinProb = [u8; ENCODED_WIN_PROB_LENGTH];
33
34/// Represents a ticket winning probability.
35///
36/// It holds the modified IEEE-754 but behaves like a reduced precision float.
37/// It intentionally does not implement `Ord` or `Eq`, as
38/// it can be only [approximately compared](WinningProbability::approx_cmp).
39#[derive(Clone, Copy, Debug)]
40#[cfg_attr(feature = "serde", derive(serde::Serialize, serde::Deserialize))]
41pub struct WinningProbability(#[cfg_attr(feature = "serde", serde(with = "serde_bytes"))] EncodedWinProb);
42
43impl WinningProbability {
44    /// 100% winning probability
45    pub const ALWAYS: Self = Self([0xff; ENCODED_WIN_PROB_LENGTH]);
46    // This value can no longer be represented with the winning probability encoding
47    // and is equal to 0
48    pub const EPSILON: f64 = 0.00000001;
49    /// 0% winning probability.
50    pub const NEVER: Self = Self([0u8; ENCODED_WIN_PROB_LENGTH]);
51
52    /// Converts winning probability to an unsigned integer (luck).
53    pub fn as_luck(&self) -> u64 {
54        let mut tmp = [0u8; 8];
55        tmp[1..].copy_from_slice(&self.0);
56        u64::from_be_bytes(tmp)
57    }
58
59    /// Convenience function to convert to internal probability representation.
60    pub fn as_encoded(&self) -> EncodedWinProb {
61        self.0
62    }
63
64    /// Convert probability to a float.
65    pub fn as_f64(&self) -> f64 {
66        if self.0.eq(&Self::NEVER.0) {
67            return 0.0;
68        }
69
70        if self.0.eq(&Self::ALWAYS.0) {
71            return 1.0;
72        }
73
74        let mut tmp = [0u8; 8];
75        tmp[1..].copy_from_slice(&self.0);
76
77        let tmp = u64::from_be_bytes(tmp);
78
79        // project interval [0x0fffffffffffff, 0x0000000000000f] to [0x00000000000010, 0x10000000000000]
80        let significand: u64 = tmp + 1;
81
82        f64::from_bits((1023u64 << 52) | (significand >> 4)) - 1.0
83    }
84
85    /// Tries to get probability from a float.
86    pub fn try_from_f64(win_prob: f64) -> errors::Result<Self> {
87        // Also makes sure the input value is not NaN or infinite.
88        if !(0.0..=1.0).contains(&win_prob) {
89            return Err(InvalidInputData("winning probability must be in [0.0, 1.0]".into()));
90        }
91
92        if f64_approx_eq(0.0, win_prob, Self::EPSILON) {
93            return Ok(Self::NEVER);
94        }
95
96        if f64_approx_eq(1.0, win_prob, Self::EPSILON) {
97            return Ok(Self::ALWAYS);
98        }
99
100        let tmp: u64 = (win_prob + 1.0).to_bits();
101
102        // // clear sign and exponent
103        let significand: u64 = tmp & 0x000fffffffffffffu64;
104
105        // project interval [0x10000000000000, 0x00000000000010] to [0x0000000000000f, 0x0fffffffffffff]
106        let encoded = ((significand - 1) << 4) | 0x000000000000000fu64;
107
108        let mut res = [0u8; 7];
109        res.copy_from_slice(&encoded.to_be_bytes()[1..]);
110
111        Ok(Self(res))
112    }
113
114    /// Performs approximate comparison up to [`Self::EPSILON`].
115    pub fn approx_cmp(&self, other: &Self) -> Ordering {
116        let a = self.as_f64();
117        let b = other.as_f64();
118        if !f64_approx_eq(a, b, Self::EPSILON) {
119            a.partial_cmp(&b).expect("finite non-NaN f64 comparison cannot fail")
120        } else {
121            Ordering::Equal
122        }
123    }
124
125    /// Performs approximate equality comparison up to [`Self::EPSILON`].
126    pub fn approx_eq(&self, other: &Self) -> bool {
127        self.approx_cmp(other) == Ordering::Equal
128    }
129
130    /// Gets the minimum of two winning probabilities.
131    pub fn min(&self, other: &Self) -> Self {
132        if self.approx_cmp(other) == Ordering::Less {
133            *self
134        } else {
135            *other
136        }
137    }
138
139    /// Gets the maximum of two winning probabilities.
140    pub fn max(&self, other: &Self) -> Self {
141        if self.approx_cmp(other) == Ordering::Greater {
142            *self
143        } else {
144            *other
145        }
146    }
147}
148
149impl Default for WinningProbability {
150    fn default() -> Self {
151        Self::ALWAYS
152    }
153}
154
155impl Display for WinningProbability {
156    fn fmt(&self, f: &mut Formatter<'_>) -> std::fmt::Result {
157        write!(f, "{:.8}", self.as_f64())
158    }
159}
160
161impl From<EncodedWinProb> for WinningProbability {
162    fn from(value: EncodedWinProb) -> Self {
163        Self(value)
164    }
165}
166
167impl<'a> From<&'a EncodedWinProb> for WinningProbability {
168    fn from(value: &'a EncodedWinProb) -> Self {
169        Self(*value)
170    }
171}
172
173impl From<WinningProbability> for EncodedWinProb {
174    fn from(value: WinningProbability) -> Self {
175        value.0
176    }
177}
178
179impl From<u64> for WinningProbability {
180    fn from(value: u64) -> Self {
181        let mut ret = Self::default();
182        ret.0.copy_from_slice(&value.to_be_bytes()[1..]);
183        ret
184    }
185}
186
187impl TryFrom<f64> for WinningProbability {
188    type Error = CoreTypesError;
189
190    fn try_from(value: f64) -> Result<Self, Self::Error> {
191        Self::try_from_f64(value)
192    }
193}
194
195impl From<WinningProbability> for f64 {
196    fn from(value: WinningProbability) -> Self {
197        value.as_f64()
198    }
199}
200
201impl PartialEq<f64> for WinningProbability {
202    fn eq(&self, other: &f64) -> bool {
203        f64_approx_eq(self.as_f64(), *other, Self::EPSILON)
204    }
205}
206
207impl PartialEq<WinningProbability> for f64 {
208    fn eq(&self, other: &WinningProbability) -> bool {
209        f64_approx_eq(*self, other.as_f64(), WinningProbability::EPSILON)
210    }
211}
212
213impl AsRef<[u8]> for WinningProbability {
214    fn as_ref(&self) -> &[u8] {
215        &self.0
216    }
217}
218
219impl<'a> TryFrom<&'a [u8]> for WinningProbability {
220    type Error = GeneralError;
221
222    fn try_from(value: &'a [u8]) -> Result<Self, Self::Error> {
223        value
224            .try_into()
225            .map(Self)
226            .map_err(|_| GeneralError::ParseError("WinningProbability".into()))
227    }
228}
229
230impl BytesRepresentable for WinningProbability {
231    const SIZE: usize = ENCODED_WIN_PROB_LENGTH;
232}
233
234/// Helper function checks if the given ticket values belong to a winning ticket.
235pub(crate) fn check_ticket_win(
236    ticket_hash: &Hash,
237    ticket_signature: &Signature,
238    win_prob: &WinningProbability,
239    response: &Response,
240    vrf_params: &VrfParameters,
241) -> bool {
242    // Computed winning probability
243    let mut computed_ticket_luck = [0u8; 8];
244    computed_ticket_luck[1..].copy_from_slice(
245        &Hash::create(&[
246            ticket_hash.as_ref(),
247            &vrf_params.V.as_uncompressed().as_bytes()[1..], // skip prefix
248            response.as_ref(),
249            ticket_signature.as_ref(),
250        ])
251        .as_ref()[0..7],
252    );
253
254    u64::from_be_bytes(computed_ticket_luck) <= win_prob.as_luck()
255}
256
257/// Builder for [Ticket] and [VerifiedTicket].
258///
259/// A new builder is created via [TicketBuilder::default] or [TicketBuilder::zero_hop].
260///
261/// Input validation is performed upon calling [TicketBuilder::build], [TicketBuilder::build_signed]
262/// and [TicketBuilder::build_verified].
263#[derive(Debug, Clone, smart_default::SmartDefault)]
264pub struct TicketBuilder {
265    channel_id: Option<Hash>,
266    amount: Option<U256>,
267    balance: Option<HoprBalance>,
268    #[default = 0]
269    index: u64,
270    #[default = 1]
271    index_offset: u32,
272    #[default = 1]
273    channel_epoch: u32,
274    win_prob: WinningProbability,
275    challenge: Option<EthereumChallenge>,
276    signature: Option<Signature>,
277}
278
279impl TicketBuilder {
280    /// Initializes the builder for a zero-hop ticket.
281    #[must_use]
282    pub fn zero_hop() -> Self {
283        Self {
284            index: 0,
285            amount: Some(U256::zero()),
286            index_offset: 1,
287            win_prob: WinningProbability::NEVER,
288            channel_epoch: 0,
289            ..Default::default()
290        }
291    }
292
293    /// Sets channel id based on the `source` and `destination`.
294    /// This, [TicketBuilder::channel_id] or [TicketBuilder::addresses] must be set.
295    #[must_use]
296    pub fn direction(mut self, source: &Address, destination: &Address) -> Self {
297        self.channel_id = Some(generate_channel_id(source, destination));
298        self
299    }
300
301    /// Sets channel id based on the `source` and `destination`.
302    /// This, [TicketBuilder::channel_id] or [TicketBuilder::direction] must be set.
303    #[must_use]
304    pub fn addresses<T: Into<Address>, U: Into<Address>>(mut self, source: T, destination: U) -> Self {
305        self.channel_id = Some(generate_channel_id(&source.into(), &destination.into()));
306        self
307    }
308
309    /// Sets the channel id.
310    /// This, [TicketBuilder::addresses] or [TicketBuilder::direction] must be set.
311    #[must_use]
312    pub fn channel_id(mut self, channel_id: Hash) -> Self {
313        self.channel_id = Some(channel_id);
314        self
315    }
316
317    /// Sets the ticket amount.
318    /// This or [TicketBuilder::balance] must be set and be less or equal to 10^25.
319    #[must_use]
320    pub fn amount<T: Into<U256>>(mut self, amount: T) -> Self {
321        self.amount = Some(amount.into());
322        self.balance = None;
323        self
324    }
325
326    /// Sets the ticket amount as HOPR balance.
327    /// This or [TicketBuilder::amount] must be set and be less or equal to 10^25.
328    #[must_use]
329    pub fn balance(mut self, balance: HoprBalance) -> Self {
330        self.balance = Some(balance);
331        self.amount = None;
332        self
333    }
334
335    /// Sets the ticket index.
336    /// Must be less or equal to 2^48.
337    /// Defaults to 0.
338    #[must_use]
339    pub fn index(mut self, index: u64) -> Self {
340        self.index = index;
341        self
342    }
343
344    /// Sets the index offset.
345    /// Must be greater or equal 1.
346    /// Defaults to 1.
347    #[must_use]
348    pub fn index_offset(mut self, index_offset: u32) -> Self {
349        self.index_offset = index_offset;
350        self
351    }
352
353    /// Sets the channel epoch.
354    /// Must be less or equal to 2^24.
355    /// Defaults to 1.
356    #[must_use]
357    pub fn channel_epoch(mut self, channel_epoch: u32) -> Self {
358        self.channel_epoch = channel_epoch;
359        self
360    }
361
362    /// Sets the ticket winning probability.
363    /// Defaults to 1.0
364    #[must_use]
365    pub fn win_prob(mut self, win_prob: WinningProbability) -> Self {
366        self.win_prob = win_prob;
367        self
368    }
369
370    /// Sets the [EthereumChallenge] for the Proof of Relay.
371    /// Must be set.
372    #[must_use]
373    pub fn challenge(mut self, challenge: EthereumChallenge) -> Self {
374        self.challenge = Some(challenge);
375        self
376    }
377
378    /// Set the signature of this ticket.
379    /// Defaults to `None`.
380    #[must_use]
381    pub fn signature(mut self, signature: Signature) -> Self {
382        self.signature = Some(signature);
383        self
384    }
385
386    /// Verifies all inputs and builds the [Ticket].
387    /// This **does not** perform signature verification if a [signature](TicketBuilder::signature)
388    /// was set.
389    pub fn build(self) -> errors::Result<Ticket> {
390        let amount = match (self.amount, self.balance) {
391            (Some(amount), None) if amount.lt(&10_u128.pow(25).into()) => HoprBalance::from(amount),
392            (None, Some(balance)) if balance.amount().lt(&10_u128.pow(25).into()) => balance,
393            (None, None) => return Err(InvalidInputData("missing ticket amount".into())),
394            (Some(_), Some(_)) => {
395                return Err(InvalidInputData(
396                    "either amount or balance must be set but not both".into(),
397                ));
398            }
399            _ => {
400                return Err(InvalidInputData(
401                    "tickets may not have more than 1% of total supply".into(),
402                ));
403            }
404        };
405
406        if self.index > (1_u64 << 48) {
407            return Err(InvalidInputData("cannot hold ticket indices larger than 2^48".into()));
408        }
409
410        if self.channel_epoch > (1_u32 << 24) {
411            return Err(InvalidInputData("cannot hold channel epoch larger than 2^24".into()));
412        }
413
414        if self.index_offset < 1 {
415            return Err(InvalidInputData(
416                "ticket index offset must be greater or equal to 1".into(),
417            ));
418        }
419
420        Ok(Ticket {
421            channel_id: self.channel_id.ok_or(InvalidInputData("missing channel id".into()))?,
422            amount,
423            index: self.index,
424            index_offset: self.index_offset,
425            encoded_win_prob: self.win_prob.into(),
426            channel_epoch: self.channel_epoch,
427            challenge: self
428                .challenge
429                .ok_or(InvalidInputData("missing ticket challenge".into()))?,
430            signature: self.signature,
431        })
432    }
433
434    /// Validates all inputs and builds the [VerifiedTicket] by signing the ticket data
435    /// with the given key. Fails if [signature](TicketBuilder::signature) was previously set.
436    pub fn build_signed(self, signer: &ChainKeypair, domain_separator: &Hash) -> errors::Result<VerifiedTicket> {
437        if self.signature.is_none() {
438            Ok(self.build()?.sign(signer, domain_separator))
439        } else {
440            Err(InvalidInputData("signature already set".into()))
441        }
442    }
443
444    /// Validates all inputs and builds the [VerifiedTicket] by **assuming** the previously
445    /// set [signature](TicketBuilder::signature) is valid and belongs to the given ticket `hash`.
446    /// It does **not** check whether `hash` matches the input data nor that the signature verifies
447    /// the given hash.
448    pub fn build_verified(self, hash: Hash) -> errors::Result<VerifiedTicket> {
449        if let Some(signature) = self.signature {
450            let issuer = PublicKey::from_signature_hash(hash.as_ref(), &signature)?.to_address();
451            Ok(VerifiedTicket(self.build()?, hash, issuer))
452        } else {
453            Err(InvalidInputData("signature is missing".into()))
454        }
455    }
456}
457
458impl From<&Ticket> for TicketBuilder {
459    fn from(value: &Ticket) -> Self {
460        Self {
461            channel_id: Some(value.channel_id),
462            amount: None,
463            balance: Some(value.amount),
464            index: value.index,
465            index_offset: value.index_offset,
466            channel_epoch: value.channel_epoch,
467            win_prob: value.encoded_win_prob.into(),
468            challenge: Some(value.challenge),
469            signature: None,
470        }
471    }
472}
473
474impl From<Ticket> for TicketBuilder {
475    fn from(value: Ticket) -> Self {
476        Self::from(&value)
477    }
478}
479
480#[cfg_attr(doc, aquamarine::aquamarine)]
481/// Contains the overall description of a ticket with a signature.
482///
483/// This structure is not considered [verified](VerifiedTicket), unless
484/// the [Ticket::verify] or [Ticket::sign] methods are called.
485///
486/// # Ticket state machine
487/// See the entire state machine describing the relations of different ticket types below:
488/// ```mermaid
489/// flowchart TB
490///     A[Ticket] -->|verify| B(VerifiedTicket)
491///     B --> |leak| A
492///     A --> |sign| B
493///     B --> |into_unacknowledged| C(UnacknowledgedTicket)
494///     B --> |into_acknowledged| D(AcknowledgedTicket)
495///     C --> |acknowledge| D
496///     D --> |into_redeemable| E(RedeemableTicket)
497///     D --> |into_transferable| F(TransferableWinningTicket)
498///     E --> |into_transferable| F
499///     F --> |into_redeemable| E
500/// ```
501#[derive(Clone, Debug, PartialEq, Eq)]
502#[cfg_attr(feature = "serde", derive(serde::Serialize, serde::Deserialize))]
503pub struct Ticket {
504    /// Channel ID.
505    /// See [generate_channel_id] for how this value is generated.
506    pub channel_id: Hash,
507    /// Amount of HOPR tokens this ticket is worth.
508    /// Always between 0 and 2^92.
509    pub amount: HoprBalance, // 92 bits
510    /// Ticket index.
511    /// Always between 0 and 2^48.
512    pub index: u64, // 48 bits
513    /// Ticket index offset.
514    /// Always between 1 and 2^32.
515    /// For normal tickets this is always equal to 1, for aggregated this is always > 1.
516    pub index_offset: u32, // 32 bits
517    /// Encoded winning probability represented via 56-bit number.
518    pub encoded_win_prob: EncodedWinProb, // 56 bits
519    /// Epoch of the channel this ticket belongs to.
520    /// Always between 0 and 2^24.
521    pub channel_epoch: u32, // 24 bits
522    /// Represent the Proof of Relay challenge encoded as an Ethereum address.
523    pub challenge: EthereumChallenge,
524    /// ECDSA secp256k1 signature of all the above values.
525    pub signature: Option<Signature>,
526}
527
528impl PartialOrd for Ticket {
529    fn partial_cmp(&self, other: &Self) -> Option<Ordering> {
530        Some(self.cmp(other))
531    }
532}
533
534impl Ord for Ticket {
535    fn cmp(&self, other: &Self) -> Ordering {
536        // Ordering:
537        // [channel_id][channel_epoch][ticket_index]
538        match self.channel_id.cmp(&other.channel_id) {
539            Ordering::Equal => match self.channel_epoch.cmp(&other.channel_epoch) {
540                Ordering::Equal => self.index.cmp(&other.index),
541                Ordering::Greater => Ordering::Greater,
542                Ordering::Less => Ordering::Less,
543            },
544            Ordering::Greater => Ordering::Greater,
545            Ordering::Less => Ordering::Less,
546        }
547    }
548}
549
550impl Display for Ticket {
551    fn fmt(&self, f: &mut Formatter<'_>) -> std::fmt::Result {
552        write!(
553            f,
554            "ticket #{}, amount {}, offset {}, epoch {} in channel {}",
555            self.index, self.amount, self.index_offset, self.channel_epoch, self.channel_id
556        )
557    }
558}
559
560impl Ticket {
561    fn encode_without_signature(&self) -> [u8; Self::SIZE - Signature::SIZE] {
562        let mut ret = [0u8; Self::SIZE - Signature::SIZE];
563        let mut offset = 0;
564
565        ret[offset..offset + Hash::SIZE].copy_from_slice(self.channel_id.as_ref());
566        offset += Hash::SIZE;
567
568        // There are only 2^96 HOPR tokens
569        ret[offset..offset + 12].copy_from_slice(&self.amount.amount().to_be_bytes()[20..32]);
570        offset += 12;
571
572        // Ticket index can go only up to 2^48
573        ret[offset..offset + 6].copy_from_slice(&self.index.to_be_bytes()[2..8]);
574        offset += 6;
575
576        ret[offset..offset + 4].copy_from_slice(&self.index_offset.to_be_bytes());
577        offset += 4;
578
579        // Channel epoch can go only up to 2^24
580        ret[offset..offset + 3].copy_from_slice(&self.channel_epoch.to_be_bytes()[1..4]);
581        offset += 3;
582
583        ret[offset..offset + ENCODED_WIN_PROB_LENGTH].copy_from_slice(&self.encoded_win_prob);
584        offset += ENCODED_WIN_PROB_LENGTH;
585
586        ret[offset..offset + EthereumChallenge::SIZE].copy_from_slice(self.challenge.as_ref());
587
588        ret
589    }
590
591    /// Computes Ethereum signature hash of the ticket,
592    /// must be equal to on-chain computation
593    pub fn get_hash(&self, domain_separator: &Hash) -> Hash {
594        let ticket_hash = Hash::create(&[self.encode_without_signature().as_ref()]); // cannot fail
595        let hash_struct = Hash::create(&[&REDEEM_CALL_SELECTOR, &[0u8; 28], ticket_hash.as_ref()]);
596        Hash::create(&[&hex!("1901"), domain_separator.as_ref(), hash_struct.as_ref()])
597    }
598
599    /// Signs the ticket using the given private key, turning this ticket into [VerifiedTicket].
600    /// If a signature was already present, it will be replaced.
601    pub fn sign(mut self, signing_key: &ChainKeypair, domain_separator: &Hash) -> VerifiedTicket {
602        let ticket_hash = self.get_hash(domain_separator);
603        self.signature = Some(Signature::sign_hash(ticket_hash.as_ref(), signing_key));
604        VerifiedTicket(self, ticket_hash, signing_key.public().to_address())
605    }
606
607    /// Verifies the signature of this ticket, turning this ticket into `VerifiedTicket`.
608    /// If the verification fails, `Self` is returned in the error.
609    ///
610    /// This is done by recovering the signer from the signature and verifying that it matches
611    /// the given `issuer` argument. This is possible due this specific instantiation of the ECDSA
612    /// over the secp256k1 curve.
613    /// The operation can fail if a public key cannot be recovered from the ticket signature.
614    pub fn verify(self, issuer: &Address, domain_separator: &Hash) -> Result<VerifiedTicket, Box<Ticket>> {
615        let ticket_hash = self.get_hash(domain_separator);
616
617        if let Some(signature) = &self.signature {
618            match PublicKey::from_signature_hash(ticket_hash.as_ref(), signature) {
619                Ok(pk) if pk.to_address().eq(issuer) => Ok(VerifiedTicket(self, ticket_hash, *issuer)),
620                Err(e) => {
621                    error!("failed to verify ticket signature: {e}");
622                    Err(self.into())
623                }
624                _ => Err(self.into()),
625            }
626        } else {
627            Err(self.into())
628        }
629    }
630
631    /// Returns true if this ticket aggregates multiple tickets.
632    pub fn is_aggregated(&self) -> bool {
633        // Aggregated tickets have always an index offset > 1
634        self.index_offset > 1
635    }
636
637    /// Returns the decoded winning probability of the ticket
638    pub fn win_prob(&self) -> WinningProbability {
639        WinningProbability(self.encoded_win_prob)
640    }
641}
642
643impl From<Ticket> for [u8; TICKET_SIZE] {
644    fn from(value: Ticket) -> Self {
645        let mut ret = [0u8; TICKET_SIZE];
646        ret[0..Ticket::SIZE - Signature::SIZE].copy_from_slice(value.encode_without_signature().as_ref());
647        ret[Ticket::SIZE - Signature::SIZE..].copy_from_slice(
648            value
649                .signature
650                .expect("cannot serialize ticket without signature")
651                .as_ref(),
652        );
653        ret
654    }
655}
656
657impl TryFrom<&[u8]> for Ticket {
658    type Error = GeneralError;
659
660    fn try_from(value: &[u8]) -> std::result::Result<Self, Self::Error> {
661        if value.len() == Self::SIZE {
662            let mut offset = 0;
663
664            // TODO: not necessary to the ChannelId over the wire, only the counterparty is sufficient
665            let channel_id = Hash::try_from(&value[offset..offset + Hash::SIZE])?;
666            offset += Hash::SIZE;
667
668            let mut amount = [0u8; 32];
669            amount[20..32].copy_from_slice(&value[offset..offset + 12]);
670            offset += 12;
671
672            let mut index = [0u8; 8];
673            index[2..8].copy_from_slice(&value[offset..offset + 6]);
674            offset += 6;
675
676            let mut index_offset = [0u8; 4];
677            index_offset.copy_from_slice(&value[offset..offset + 4]);
678            offset += 4;
679
680            let mut channel_epoch = [0u8; 4];
681            channel_epoch[1..4].copy_from_slice(&value[offset..offset + 3]);
682            offset += 3;
683
684            let win_prob = WinningProbability::try_from(&value[offset..offset + WinningProbability::SIZE])?;
685            offset += WinningProbability::SIZE;
686
687            debug_assert_eq!(offset, ENCODED_TICKET_LENGTH);
688
689            let challenge = EthereumChallenge::try_from(&value[offset..offset + EthereumChallenge::SIZE])?;
690            offset += EthereumChallenge::SIZE;
691
692            let signature = Signature::try_from(&value[offset..offset + Signature::SIZE])?;
693
694            // Validate the boundaries of the parsed values
695            TicketBuilder::default()
696                .channel_id(channel_id)
697                .amount(U256::from_big_endian(&amount))
698                .index(u64::from_be_bytes(index))
699                .index_offset(u32::from_be_bytes(index_offset))
700                .channel_epoch(u32::from_be_bytes(channel_epoch))
701                .win_prob(win_prob)
702                .challenge(challenge)
703                .signature(signature)
704                .build()
705                .map_err(|e| GeneralError::ParseError(format!("ticket build failed: {e}")))
706        } else {
707            Err(GeneralError::ParseError("Ticket".into()))
708        }
709    }
710}
711
712const TICKET_SIZE: usize = ENCODED_TICKET_LENGTH + EthereumChallenge::SIZE + Signature::SIZE;
713
714impl BytesEncodable<TICKET_SIZE> for Ticket {}
715
716/// Holds a ticket that has been already verified.
717/// This structure guarantees that [`Ticket::get_hash()`] of [`VerifiedTicket::verified_ticket()`]
718/// is always equal to [`VerifiedTicket::verified_hash`]
719#[derive(Debug, Clone, PartialEq, Eq)]
720#[cfg_attr(feature = "serde", derive(serde::Serialize, serde::Deserialize))]
721pub struct VerifiedTicket(Ticket, Hash, Address);
722
723impl VerifiedTicket {
724    /// Returns the verified encoded winning probability of the ticket
725    pub fn win_prob(&self) -> WinningProbability {
726        self.0.win_prob()
727    }
728
729    /// Checks if this ticket is considered a win.
730    /// Requires access to the private key to compute the VRF values.
731    ///
732    /// Computes the ticket's luck value and compares it against the
733    /// ticket's probability. If luck <= probability, the ticket is
734    /// considered a win.
735    ///
736    /// ## Ticket luck value
737    /// This ticket's `luck value` is the first 7 bytes of Keccak256 hash
738    /// of the concatenation of ticket's hash, VRF's encoded `v` value,
739    /// PoR response and the ticket's signature.
740    ///
741    /// ## Winning probability
742    /// Each ticket specifies a probability, given as an integer in
743    /// [0, 2^56 - 1] where 0 -> 0% and 2^56 - 1 -> 100% win
744    /// probability. If the ticket's luck value is greater than
745    /// the stated probability, it is considered a winning ticket.
746    pub fn is_winning(&self, response: &Response, chain_keypair: &ChainKeypair, domain_separator: &Hash) -> bool {
747        if let Ok(vrf_params) = derive_vrf_parameters(self.1, chain_keypair, domain_separator.as_ref()) {
748            check_ticket_win(
749                &self.1,
750                self.0
751                    .signature
752                    .as_ref()
753                    .expect("verified ticket have always a signature"),
754                &self.0.win_prob(),
755                response,
756                &vrf_params,
757            )
758        } else {
759            error!("cannot derive vrf parameters for {self}");
760            false
761        }
762    }
763
764    /// Ticket with already verified signature.
765    pub fn verified_ticket(&self) -> &Ticket {
766        &self.0
767    }
768
769    /// Fixed ticket hash that is guaranteed to be equal to
770    /// [`Ticket::get_hash`] of [`VerifiedTicket::verified_ticket`].
771    pub fn verified_hash(&self) -> &Hash {
772        &self.1
773    }
774
775    /// Verified issuer of the ticket.
776    /// The returned address is guaranteed to be equal to the signer
777    /// recovered from the [`VerifiedTicket::verified_ticket`]'s signature.
778    pub fn verified_issuer(&self) -> &Address {
779        &self.2
780    }
781
782    /// Shorthand to retrieve reference to the verified ticket signature
783    pub fn verified_signature(&self) -> &Signature {
784        self.0
785            .signature
786            .as_ref()
787            .expect("verified ticket always has a signature")
788    }
789
790    /// Deconstructs self back into the unverified [Ticket].
791    pub fn leak(self) -> Ticket {
792        self.0
793    }
794
795    /// Creates a new unacknowledged ticket from the [VerifiedTicket],
796    /// given our own part of the PoR challenge.
797    pub fn into_unacknowledged(self, own_key: HalfKey) -> UnacknowledgedTicket {
798        UnacknowledgedTicket { ticket: self, own_key }
799    }
800
801    /// Shorthand to acknowledge the ticket if the matching response is already known.
802    /// This is used upon receiving an aggregated ticket.
803    pub fn into_acknowledged(self, response: Response) -> AcknowledgedTicket {
804        AcknowledgedTicket {
805            status: AcknowledgedTicketStatus::Untouched,
806            ticket: self,
807            response,
808        }
809    }
810}
811
812impl Display for VerifiedTicket {
813    fn fmt(&self, f: &mut Formatter<'_>) -> std::fmt::Result {
814        write!(f, "verified {}", self.0)
815    }
816}
817
818impl PartialOrd for VerifiedTicket {
819    fn partial_cmp(&self, other: &Self) -> Option<Ordering> {
820        Some(self.cmp(other))
821    }
822}
823
824impl Ord for VerifiedTicket {
825    fn cmp(&self, other: &Self) -> Ordering {
826        self.0.cmp(&other.0)
827    }
828}
829
830/// Represents a [VerifiedTicket] with an unknown other part of the [HalfKey].
831/// Once the other [HalfKey] is known (forming a [Response]),
832/// it can be [acknowledged](UnacknowledgedTicket::acknowledge).
833#[derive(Clone, Debug, PartialEq, Eq)]
834#[cfg_attr(feature = "serde", derive(serde::Serialize, serde::Deserialize))]
835pub struct UnacknowledgedTicket {
836    pub ticket: VerifiedTicket,
837    pub(crate) own_key: HalfKey,
838}
839
840impl UnacknowledgedTicket {
841    /// Convenience method to retrieve a reference to the underlying verified [Ticket].
842    #[inline]
843    pub fn verified_ticket(&self) -> &Ticket {
844        self.ticket.verified_ticket()
845    }
846
847    /// Verifies that the given acknowledgement solves this ticket's challenge and then
848    /// turns this unacknowledged ticket into an acknowledged ticket by adding
849    /// the received acknowledgement of the forwarded packet.
850    pub fn acknowledge(self, acknowledgement: &HalfKey) -> crate::errors::Result<AcknowledgedTicket> {
851        let response = Response::from_half_keys(&self.own_key, acknowledgement)?;
852        debug!(ticket = %self.ticket, response = response.to_hex(), "acknowledging ticket using response");
853
854        if self.ticket.verified_ticket().challenge == response.to_challenge().into() {
855            Ok(self.ticket.into_acknowledged(response))
856        } else {
857            Err(CryptoError::InvalidChallenge.into())
858        }
859    }
860}
861
862/// Status of the acknowledged ticket.
863#[repr(u8)]
864#[derive(
865    Clone,
866    Copy,
867    Debug,
868    Default,
869    Eq,
870    PartialEq,
871    strum::Display,
872    strum::EnumString,
873    num_enum::IntoPrimitive,
874    num_enum::TryFromPrimitive,
875)]
876#[cfg_attr(feature = "serde", derive(serde::Serialize, serde::Deserialize))]
877#[strum(serialize_all = "PascalCase")]
878pub enum AcknowledgedTicketStatus {
879    /// The ticket is available for redeeming or aggregating
880    #[default]
881    Untouched = 0,
882    /// Ticket is currently being redeemed in and ongoing redemption process
883    BeingRedeemed = 1,
884    /// Ticket is currently being aggregated in and ongoing aggregation process
885    BeingAggregated = 2,
886}
887
888/// Contains acknowledgment information and the respective ticket
889#[derive(Clone, Debug, PartialEq, Eq)]
890#[cfg_attr(feature = "serde", derive(serde::Serialize, serde::Deserialize))]
891pub struct AcknowledgedTicket {
892    #[cfg_attr(feature = "serde", serde(default))]
893    pub status: AcknowledgedTicketStatus,
894    pub ticket: VerifiedTicket,
895    pub response: Response,
896}
897
898impl PartialOrd for AcknowledgedTicket {
899    fn partial_cmp(&self, other: &Self) -> Option<std::cmp::Ordering> {
900        Some(self.cmp(other))
901    }
902}
903
904impl Ord for AcknowledgedTicket {
905    fn cmp(&self, other: &Self) -> std::cmp::Ordering {
906        self.ticket.cmp(&other.ticket)
907    }
908}
909
910impl AcknowledgedTicket {
911    /// Convenience method to retrieve a reference to the underlying verified [Ticket].
912    #[inline]
913    pub fn verified_ticket(&self) -> &Ticket {
914        self.ticket.verified_ticket()
915    }
916
917    /// Checks if this acknowledged ticket is winning.
918    pub fn is_winning(&self, chain_keypair: &ChainKeypair, domain_separator: &Hash) -> bool {
919        self.ticket.is_winning(&self.response, chain_keypair, domain_separator)
920    }
921
922    /// Transforms this ticket into [RedeemableTicket] that can be redeemed on-chain
923    /// or transformed into [TransferableWinningTicket] that can be sent for aggregation.
924    /// The `chain_keypair` must not be of the ticket's issuer.
925    pub fn into_redeemable(
926        self,
927        chain_keypair: &ChainKeypair,
928        domain_separator: &Hash,
929    ) -> crate::errors::Result<RedeemableTicket> {
930        // This function must be called by ticket recipient and not the issuer
931        if chain_keypair.public().to_address().eq(self.ticket.verified_issuer()) {
932            return Err(errors::CoreTypesError::LoopbackTicket);
933        }
934
935        let vrf_params = derive_vrf_parameters(self.ticket.verified_hash(), chain_keypair, domain_separator.as_ref())?;
936
937        Ok(RedeemableTicket {
938            ticket: self.ticket,
939            response: self.response,
940            vrf_params,
941            channel_dst: *domain_separator,
942        })
943    }
944
945    /// Shorthand for transforming this ticket into [TransferableWinningTicket].
946    /// See [`AcknowledgedTicket::into_redeemable`] for details.
947    pub fn into_transferable(
948        self,
949        chain_keypair: &ChainKeypair,
950        domain_separator: &Hash,
951    ) -> errors::Result<TransferableWinningTicket> {
952        self.into_redeemable(chain_keypair, domain_separator)
953            .map(TransferableWinningTicket::from)
954    }
955}
956
957impl Display for AcknowledgedTicket {
958    fn fmt(&self, f: &mut Formatter<'_>) -> std::fmt::Result {
959        write!(f, "acknowledged {} in state '{}'", self.ticket, self.status)
960    }
961}
962
963/// Represents a winning ticket that can be successfully redeemed on-chain.
964#[derive(Clone, Debug)]
965#[cfg_attr(feature = "serde", derive(serde::Serialize, serde::Deserialize))]
966pub struct RedeemableTicket {
967    /// Verified ticket that can be redeemed.
968    pub ticket: VerifiedTicket,
969    /// Solution to the PoR challenge in the ticket.
970    pub response: Response,
971    /// VRF parameters required for redeeming.
972    pub vrf_params: VrfParameters,
973    /// Channel domain separator used to compute the VRF parameters.
974    pub channel_dst: Hash,
975}
976
977impl RedeemableTicket {
978    /// Convenience method to retrieve a reference to the underlying verified [Ticket].
979    #[inline]
980    pub fn verified_ticket(&self) -> &Ticket {
981        self.ticket.verified_ticket()
982    }
983}
984
985impl PartialEq for RedeemableTicket {
986    fn eq(&self, other: &Self) -> bool {
987        self.ticket == other.ticket && self.channel_dst == other.channel_dst && self.response == other.response
988    }
989}
990
991impl Display for RedeemableTicket {
992    fn fmt(&self, f: &mut Formatter<'_>) -> std::fmt::Result {
993        write!(f, "redeemable {}", self.ticket)
994    }
995}
996
997impl From<RedeemableTicket> for AcknowledgedTicket {
998    fn from(value: RedeemableTicket) -> Self {
999        Self {
1000            status: AcknowledgedTicketStatus::Untouched,
1001            ticket: value.ticket,
1002            response: value.response,
1003        }
1004    }
1005}
1006
1007/// Represents a ticket that could be transferred over the wire
1008/// and independently verified again by the other party.
1009///
1010/// The [TransferableWinningTicket] can be easily retrieved from [RedeemableTicket], which strips
1011/// information about verification.
1012/// [TransferableWinningTicket] can be attempted to be converted back to [RedeemableTicket] only
1013/// when verified via [`TransferableWinningTicket::into_redeemable`] again.
1014#[derive(Debug, Clone)]
1015#[cfg_attr(feature = "serde", derive(serde::Serialize, serde::Deserialize))]
1016pub struct TransferableWinningTicket {
1017    pub ticket: Ticket,
1018    pub response: Response,
1019    pub vrf_params: VrfParameters,
1020    pub signer: Address,
1021}
1022
1023impl TransferableWinningTicket {
1024    /// Attempts to transform this ticket back into a [RedeemableTicket].
1025    ///
1026    /// Verifies that the `signer` matches the `expected_issuer` and that the
1027    /// ticket has a valid signature from the `signer`.
1028    /// Then it verifies if the ticket is winning and therefore if it can be successfully
1029    /// redeemed on-chain.
1030    pub fn into_redeemable(
1031        self,
1032        expected_issuer: &Address,
1033        domain_separator: &Hash,
1034    ) -> errors::Result<RedeemableTicket> {
1035        if !self.signer.eq(expected_issuer) {
1036            return Err(crate::errors::CoreTypesError::InvalidInputData(
1037                "invalid ticket issuer".into(),
1038            ));
1039        }
1040
1041        let verified_ticket = self
1042            .ticket
1043            .verify(&self.signer, domain_separator)
1044            .map_err(|_| CoreTypesError::CryptoError(CryptoError::SignatureVerification))?;
1045
1046        if check_ticket_win(
1047            verified_ticket.verified_hash(),
1048            verified_ticket.verified_signature(),
1049            &verified_ticket.verified_ticket().win_prob(),
1050            &self.response,
1051            &self.vrf_params,
1052        ) {
1053            Ok(RedeemableTicket {
1054                ticket: verified_ticket,
1055                response: self.response,
1056                vrf_params: self.vrf_params,
1057                channel_dst: *domain_separator,
1058            })
1059        } else {
1060            Err(crate::errors::CoreTypesError::InvalidInputData(
1061                "ticket is not a win".into(),
1062            ))
1063        }
1064    }
1065}
1066
1067impl PartialEq for TransferableWinningTicket {
1068    fn eq(&self, other: &Self) -> bool {
1069        self.ticket == other.ticket && self.signer == other.signer && self.response == other.response
1070    }
1071}
1072
1073impl PartialOrd<Self> for TransferableWinningTicket {
1074    fn partial_cmp(&self, other: &Self) -> Option<Ordering> {
1075        Some(self.ticket.cmp(&other.ticket))
1076    }
1077}
1078
1079impl From<RedeemableTicket> for TransferableWinningTicket {
1080    fn from(value: RedeemableTicket) -> Self {
1081        Self {
1082            response: value.response,
1083            vrf_params: value.vrf_params,
1084            signer: *value.ticket.verified_issuer(),
1085            ticket: value.ticket.leak(),
1086        }
1087    }
1088}
1089
1090#[cfg(test)]
1091pub mod tests {
1092    use hex_literal::hex;
1093    use hopr_crypto_random::Randomizable;
1094    use hopr_crypto_types::{
1095        keypairs::{ChainKeypair, Keypair},
1096        types::{Challenge, CurvePoint, HalfKey, Hash, Response},
1097    };
1098    use hopr_primitive_types::{
1099        prelude::UnitaryFloatOps,
1100        primitives::{Address, EthereumChallenge, U256},
1101    };
1102
1103    use super::*;
1104
1105    lazy_static::lazy_static! {
1106        static ref ALICE: ChainKeypair = ChainKeypair::from_secret(&hex!("492057cf93e99b31d2a85bc5e98a9c3aa0021feec52c227cc8170e8f7d047775")).expect("lazy static keypair should be constructible");
1107        static ref BOB: ChainKeypair = ChainKeypair::from_secret(&hex!("48680484c6fc31bc881a0083e6e32b6dc789f9eaba0f8b981429fd346c697f8c")).expect("lazy static keypair should be constructible");
1108    }
1109
1110    #[cfg(feature = "serde")]
1111    const BINCODE_CONFIGURATION: bincode::config::Configuration = bincode::config::standard()
1112        .with_little_endian()
1113        .with_variable_int_encoding();
1114
1115    #[test]
1116    pub fn test_win_prob_to_f64() -> anyhow::Result<()> {
1117        assert_eq!(0.0f64, WinningProbability::NEVER.as_f64());
1118
1119        assert_eq!(1.0f64, WinningProbability::ALWAYS.as_f64());
1120
1121        let mut test_bit_string = [0xffu8; 7];
1122        test_bit_string[0] = 0x7f;
1123        assert_eq!(0.5f64, WinningProbability::from(&test_bit_string).as_f64());
1124
1125        test_bit_string[0] = 0x3f;
1126        assert_eq!(0.25f64, WinningProbability::from(&test_bit_string).as_f64());
1127
1128        test_bit_string[0] = 0x1f;
1129        assert_eq!(0.125f64, WinningProbability::from(&test_bit_string).as_f64());
1130
1131        Ok(())
1132    }
1133
1134    #[test]
1135    pub fn test_f64_to_win_prob() -> anyhow::Result<()> {
1136        assert_eq!([0u8; 7], WinningProbability::try_from(0.0f64)?.as_encoded());
1137
1138        let mut test_bit_string = [0xffu8; 7];
1139        assert_eq!(test_bit_string, WinningProbability::try_from(1.0f64)?.as_encoded());
1140
1141        test_bit_string[0] = 0x7f;
1142        assert_eq!(test_bit_string, WinningProbability::try_from(0.5f64)?.as_encoded());
1143
1144        test_bit_string[0] = 0x3f;
1145        assert_eq!(test_bit_string, WinningProbability::try_from(0.25f64)?.as_encoded());
1146
1147        test_bit_string[0] = 0x1f;
1148        assert_eq!(test_bit_string, WinningProbability::try_from(0.125f64)?.as_encoded());
1149
1150        Ok(())
1151    }
1152
1153    #[test]
1154    pub fn test_win_prob_approx_eq() -> anyhow::Result<()> {
1155        let wp_0 = WinningProbability(hex!("0020C49BBFFFFF"));
1156        let wp_1 = WinningProbability(hex!("0020C49BA5E34F"));
1157
1158        assert_ne!(wp_0.as_ref(), wp_1.as_ref());
1159        assert_eq!(wp_0, wp_1.as_f64());
1160
1161        Ok(())
1162    }
1163
1164    #[test]
1165    pub fn test_win_prob_back_and_forth() -> anyhow::Result<()> {
1166        for float in [0.1f64, 0.002f64, 0.00001f64, 0.7311111f64, 1.0f64, 0.0f64] {
1167            assert!((float - WinningProbability::try_from_f64(float)?.as_f64()).abs() < f64::EPSILON);
1168        }
1169
1170        Ok(())
1171    }
1172
1173    #[test]
1174    pub fn test_win_prob_must_be_correctly_ordered() {
1175        let increment = WinningProbability::EPSILON * 100.0; // Testing the entire range would take too long
1176        let mut prev = WinningProbability::NEVER;
1177        while let Ok(next) = WinningProbability::try_from_f64(prev.as_f64() + increment) {
1178            assert!(prev.approx_cmp(&next).is_lt());
1179            prev = next;
1180        }
1181    }
1182
1183    #[test]
1184    pub fn test_win_prob_epsilon_must_be_never() -> anyhow::Result<()> {
1185        assert!(WinningProbability::NEVER.approx_eq(&WinningProbability::try_from_f64(WinningProbability::EPSILON)?));
1186        Ok(())
1187    }
1188
1189    #[test]
1190    pub fn test_win_prob_bounds_must_be_eq() -> anyhow::Result<()> {
1191        let bound = 0.1 + WinningProbability::EPSILON;
1192        let other = 0.1;
1193        assert!(WinningProbability::try_from_f64(bound)?.approx_eq(&WinningProbability::try_from_f64(other)?));
1194        Ok(())
1195    }
1196
1197    #[test]
1198    pub fn test_ticket_builder_zero_hop() -> anyhow::Result<()> {
1199        let ticket = TicketBuilder::zero_hop()
1200            .direction(&ALICE.public().to_address(), &BOB.public().to_address())
1201            .challenge(Default::default())
1202            .build()?;
1203        assert_eq!(0, ticket.index);
1204        assert_eq!(0.0, ticket.win_prob().as_f64());
1205        assert_eq!(0, ticket.channel_epoch);
1206        assert_eq!(
1207            generate_channel_id(&ALICE.public().to_address(), &BOB.public().to_address()),
1208            ticket.channel_id
1209        );
1210        Ok(())
1211    }
1212
1213    #[test]
1214    pub fn test_ticket_serialize_deserialize() -> anyhow::Result<()> {
1215        let initial_ticket = TicketBuilder::default()
1216            .direction(&ALICE.public().to_address(), &BOB.public().to_address())
1217            .balance(1.into())
1218            .index(0)
1219            .index_offset(1)
1220            .win_prob(1.0.try_into()?)
1221            .channel_epoch(1)
1222            .challenge(Default::default())
1223            .build_signed(&ALICE, &Default::default())?;
1224
1225        assert_ne!(initial_ticket.verified_hash().as_ref(), [0u8; Hash::SIZE]);
1226
1227        let ticket_bytes: [u8; Ticket::SIZE] = initial_ticket.verified_ticket().clone().into();
1228        assert_eq!(
1229            initial_ticket.verified_ticket(),
1230            &Ticket::try_from(ticket_bytes.as_ref())?
1231        );
1232        Ok(())
1233    }
1234
1235    #[test]
1236    #[cfg(feature = "serde")]
1237    pub fn test_ticket_serialize_deserialize_serde() -> anyhow::Result<()> {
1238        let initial_ticket = TicketBuilder::default()
1239            .direction(&ALICE.public().to_address(), &BOB.public().to_address())
1240            .balance(1.into())
1241            .index(0)
1242            .index_offset(1)
1243            .win_prob(1.0.try_into()?)
1244            .channel_epoch(1)
1245            .challenge(Default::default())
1246            .build_signed(&ALICE, &Default::default())?;
1247
1248        assert_eq!(
1249            initial_ticket,
1250            bincode::serde::decode_from_slice(
1251                &bincode::serde::encode_to_vec(&initial_ticket, BINCODE_CONFIGURATION)?,
1252                BINCODE_CONFIGURATION
1253            )
1254            .map(|v| v.0)?
1255        );
1256        Ok(())
1257    }
1258
1259    #[test]
1260    pub fn test_ticket_sign_verify() -> anyhow::Result<()> {
1261        let initial_ticket = TicketBuilder::default()
1262            .direction(&ALICE.public().to_address(), &BOB.public().to_address())
1263            .balance(1.into())
1264            .index(0)
1265            .index_offset(1)
1266            .win_prob(1.0.try_into()?)
1267            .channel_epoch(1)
1268            .challenge(Default::default())
1269            .build_signed(&ALICE, &Default::default())?;
1270
1271        assert_ne!(initial_ticket.verified_hash().as_ref(), [0u8; Hash::SIZE]);
1272
1273        let ticket = initial_ticket.leak();
1274        assert!(ticket.verify(&ALICE.public().to_address(), &Default::default()).is_ok());
1275        Ok(())
1276    }
1277
1278    #[test]
1279    pub fn test_zero_hop() -> anyhow::Result<()> {
1280        let ticket = TicketBuilder::zero_hop()
1281            .direction(&ALICE.public().to_address(), &BOB.public().to_address())
1282            .challenge(Default::default())
1283            .build_signed(&ALICE, &Default::default())?;
1284
1285        assert!(
1286            ticket
1287                .leak()
1288                .verify(&ALICE.public().to_address(), &Hash::default())
1289                .is_ok()
1290        );
1291        Ok(())
1292    }
1293
1294    fn mock_ticket(
1295        pk: &ChainKeypair,
1296        counterparty: &Address,
1297        domain_separator: Option<Hash>,
1298        challenge: Option<EthereumChallenge>,
1299    ) -> anyhow::Result<VerifiedTicket> {
1300        let win_prob = 1.0f64; // 100 %
1301        let price_per_packet: U256 = 10000000000000000u128.into(); // 0.01 HOPR
1302        let path_pos = 5u64;
1303
1304        Ok(TicketBuilder::default()
1305            .direction(&pk.public().to_address(), counterparty)
1306            .amount(price_per_packet.div_f64(win_prob)? * U256::from(path_pos))
1307            .index(0)
1308            .index_offset(1)
1309            .win_prob(1.0.try_into()?)
1310            .channel_epoch(4)
1311            .challenge(challenge.unwrap_or_default())
1312            .build_signed(pk, &domain_separator.unwrap_or_default())?)
1313    }
1314
1315    #[test]
1316    fn test_unacknowledged_ticket_challenge_response() -> anyhow::Result<()> {
1317        let hk1 = HalfKey::try_from(hex!("3477d7de923ba3a7d5d72a7d6c43fd78395453532d03b2a1e2b9a7cc9b61bafa").as_ref())?;
1318
1319        let hk2 = HalfKey::try_from(hex!("4471496ef88d9a7d86a92b7676f3c8871a60792a37fae6fc3abc347c3aa3b16b").as_ref())?;
1320
1321        let cp1: CurvePoint = hk1.to_challenge().try_into()?;
1322        let cp2: CurvePoint = hk2.to_challenge().try_into()?;
1323        let cp_sum = CurvePoint::combine(&[&cp1, &cp2]);
1324
1325        let dst = Hash::default();
1326        let ack = mock_ticket(
1327            &ALICE,
1328            &BOB.public().to_address(),
1329            Some(dst),
1330            Some(Challenge::from(cp_sum).to_ethereum_challenge()),
1331        )?
1332        .into_unacknowledged(hk1)
1333        .acknowledge(&hk2)?;
1334
1335        assert!(ack.is_winning(&BOB, &dst), "ticket must be winning");
1336        Ok(())
1337    }
1338
1339    #[test]
1340    #[cfg(feature = "serde")]
1341    fn test_acknowledged_ticket_serde() -> anyhow::Result<()> {
1342        let response =
1343            Response::try_from(hex!("876a41ee5fb2d27ac14d8e8d552692149627c2f52330ba066f9e549aef762f73").as_ref())?;
1344
1345        let dst = Hash::default();
1346
1347        let ticket = mock_ticket(
1348            &ALICE,
1349            &BOB.public().to_address(),
1350            Some(dst),
1351            Some(response.to_challenge().into()),
1352        )?;
1353
1354        let acked_ticket = ticket.into_acknowledged(response);
1355
1356        let mut deserialized_ticket = bincode::serde::decode_from_slice(
1357            &bincode::serde::encode_to_vec(&acked_ticket, BINCODE_CONFIGURATION)?,
1358            BINCODE_CONFIGURATION,
1359        )
1360        .map(|v| v.0)?;
1361        assert_eq!(acked_ticket, deserialized_ticket);
1362
1363        assert!(deserialized_ticket.is_winning(&BOB, &dst));
1364
1365        deserialized_ticket.status = super::AcknowledgedTicketStatus::BeingAggregated;
1366
1367        assert_eq!(
1368            deserialized_ticket,
1369            bincode::serde::decode_from_slice(
1370                &bincode::serde::encode_to_vec(&deserialized_ticket, BINCODE_CONFIGURATION)?,
1371                BINCODE_CONFIGURATION,
1372            )
1373            .map(|v| v.0)?
1374        );
1375        Ok(())
1376    }
1377
1378    #[test]
1379    fn test_ticket_entire_ticket_transfer_flow() -> anyhow::Result<()> {
1380        let hk1 = HalfKey::random();
1381        let hk2 = HalfKey::random();
1382        let resp = Response::from_half_keys(&hk1, &hk2)?;
1383
1384        let verified = TicketBuilder::default()
1385            .direction(&ALICE.public().to_address(), &BOB.public().to_address())
1386            .balance(1.into())
1387            .index(0)
1388            .index_offset(1)
1389            .win_prob(1.0.try_into()?)
1390            .channel_epoch(1)
1391            .challenge(resp.to_challenge().to_ethereum_challenge())
1392            .build_signed(&ALICE, &Default::default())?;
1393
1394        let unack = verified.into_unacknowledged(hk1);
1395        let acknowledged = unack.acknowledge(&hk2).expect("should acknowledge");
1396
1397        let redeemable_1 = acknowledged.clone().into_redeemable(&BOB, &Hash::default())?;
1398
1399        let transferable = acknowledged.into_transferable(&BOB, &Hash::default())?;
1400
1401        let redeemable_2 = transferable.into_redeemable(&ALICE.public().to_address(), &Hash::default())?;
1402
1403        assert_eq!(redeemable_1, redeemable_2);
1404        assert_eq!(redeemable_1.vrf_params.V, redeemable_2.vrf_params.V);
1405        Ok(())
1406    }
1407}
hopr_internal_types/tickets.rs

hopr_internal_types/
tickets.rs
