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, instrument};
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.get_v_encoded_point().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 [`Challenge`] for the Proof of Relay, converting it to [`EthereumChallenge`] first.
371    ///
372    /// Either this method or [`Ticket::eth_challenge`] must be called.
373    #[must_use]
374    pub fn challenge(mut self, challenge: Challenge) -> Self {
375        self.challenge = Some(challenge.to_ethereum_challenge());
376        self
377    }
378
379    /// Sets the [`EthereumChallenge`] for the Proof of Relay.
380    /// Either this method or [`Ticket::challenge`] must be called.
381    pub fn eth_challenge(mut self, challenge: EthereumChallenge) -> Self {
382        self.challenge = Some(challenge);
383        self
384    }
385
386    /// Set the signature of this ticket.
387    /// Defaults to `None`.
388    #[must_use]
389    pub fn signature(mut self, signature: Signature) -> Self {
390        self.signature = Some(signature);
391        self
392    }
393
394    /// Verifies all inputs and builds the [Ticket].
395    /// This **does not** perform signature verification if a [signature](TicketBuilder::signature)
396    /// was set.
397    pub fn build(self) -> errors::Result<Ticket> {
398        let amount = match (self.amount, self.balance) {
399            (Some(amount), None) if amount.lt(&10_u128.pow(25).into()) => HoprBalance::from(amount),
400            (None, Some(balance)) if balance.amount().lt(&10_u128.pow(25).into()) => balance,
401            (None, None) => return Err(InvalidInputData("missing ticket amount".into())),
402            (Some(_), Some(_)) => {
403                return Err(InvalidInputData(
404                    "either amount or balance must be set but not both".into(),
405                ));
406            }
407            _ => {
408                return Err(InvalidInputData(
409                    "tickets may not have more than 1% of total supply".into(),
410                ));
411            }
412        };
413
414        if self.index > (1_u64 << 48) {
415            return Err(InvalidInputData("cannot hold ticket indices larger than 2^48".into()));
416        }
417
418        if self.channel_epoch > (1_u32 << 24) {
419            return Err(InvalidInputData("cannot hold channel epoch larger than 2^24".into()));
420        }
421
422        if self.index_offset < 1 {
423            return Err(InvalidInputData(
424                "ticket index offset must be greater or equal to 1".into(),
425            ));
426        }
427
428        Ok(Ticket {
429            channel_id: self.channel_id.ok_or(InvalidInputData("missing channel id".into()))?,
430            amount,
431            index: self.index,
432            index_offset: self.index_offset,
433            encoded_win_prob: self.win_prob.into(),
434            channel_epoch: self.channel_epoch,
435            challenge: self
436                .challenge
437                .ok_or(InvalidInputData("missing ticket challenge".into()))?,
438            signature: self.signature,
439        })
440    }
441
442    /// Validates all inputs and builds the [VerifiedTicket] by signing the ticket data
443    /// with the given key. Fails if [signature](TicketBuilder::signature) was previously set.
444    pub fn build_signed(self, signer: &ChainKeypair, domain_separator: &Hash) -> errors::Result<VerifiedTicket> {
445        if self.signature.is_none() {
446            Ok(self.build()?.sign(signer, domain_separator))
447        } else {
448            Err(InvalidInputData("signature already set".into()))
449        }
450    }
451
452    /// Validates all inputs and builds the [VerifiedTicket] by **assuming** the previously
453    /// set [signature](TicketBuilder::signature) is valid and belongs to the given ticket `hash`.
454    /// It does **not** check whether `hash` matches the input data nor that the signature verifies
455    /// the given hash.
456    pub fn build_verified(self, hash: Hash) -> errors::Result<VerifiedTicket> {
457        if let Some(signature) = self.signature {
458            let issuer = signature.recover_from_hash(&hash)?.to_address();
459            Ok(VerifiedTicket(self.build()?, hash, issuer))
460        } else {
461            Err(InvalidInputData("signature is missing".into()))
462        }
463    }
464}
465
466impl From<&Ticket> for TicketBuilder {
467    fn from(value: &Ticket) -> Self {
468        Self {
469            channel_id: Some(value.channel_id),
470            amount: None,
471            balance: Some(value.amount),
472            index: value.index,
473            index_offset: value.index_offset,
474            channel_epoch: value.channel_epoch,
475            win_prob: value.encoded_win_prob.into(),
476            challenge: Some(value.challenge),
477            signature: None,
478        }
479    }
480}
481
482impl From<Ticket> for TicketBuilder {
483    fn from(value: Ticket) -> Self {
484        Self::from(&value)
485    }
486}
487
488#[cfg_attr(doc, aquamarine::aquamarine)]
489/// Contains the overall description of a ticket with a signature.
490///
491/// This structure is not considered [verified](VerifiedTicket), unless
492/// the [Ticket::verify] or [Ticket::sign] methods are called.
493///
494/// # Ticket state machine
495/// See the entire state machine describing the relations of different ticket types below:
496/// ```mermaid
497/// flowchart TB
498///     A[Ticket] -->|verify| B(VerifiedTicket)
499///     B --> |leak| A
500///     A --> |sign| B
501///     B --> |into_unacknowledged| C(UnacknowledgedTicket)
502///     B --> |into_acknowledged| D(AcknowledgedTicket)
503///     C --> |acknowledge| D
504///     D --> |into_redeemable| E(RedeemableTicket)
505///     D --> |into_transferable| F(TransferableWinningTicket)
506///     E --> |into_transferable| F
507///     F --> |into_redeemable| E
508/// ```
509#[derive(Clone, Debug, PartialEq, Eq)]
510#[cfg_attr(feature = "serde", derive(serde::Serialize, serde::Deserialize))]
511pub struct Ticket {
512    /// Channel ID.
513    /// See [generate_channel_id] for how this value is generated.
514    pub channel_id: Hash,
515    /// Amount of HOPR tokens this ticket is worth.
516    /// Always between 0 and 2^92.
517    pub amount: HoprBalance, // 92 bits
518    /// Ticket index.
519    /// Always between 0 and 2^48.
520    pub index: u64, // 48 bits
521    /// Ticket index offset.
522    /// Always between 1 and 2^32.
523    /// For normal tickets this is always equal to 1, for aggregated this is always > 1.
524    pub index_offset: u32, // 32 bits
525    /// Encoded winning probability represented via 56-bit number.
526    pub encoded_win_prob: EncodedWinProb, // 56 bits
527    /// Epoch of the channel this ticket belongs to.
528    /// Always between 0 and 2^24.
529    pub channel_epoch: u32, // 24 bits
530    /// Represent the Proof of Relay challenge encoded as an Ethereum address.
531    pub challenge: EthereumChallenge,
532    /// ECDSA secp256k1 signature of all the above values.
533    pub signature: Option<Signature>,
534}
535
536impl PartialOrd for Ticket {
537    fn partial_cmp(&self, other: &Self) -> Option<Ordering> {
538        Some(self.cmp(other))
539    }
540}
541
542impl Ord for Ticket {
543    fn cmp(&self, other: &Self) -> Ordering {
544        // Ordering:
545        // [channel_id][channel_epoch][ticket_index]
546        match self.channel_id.cmp(&other.channel_id) {
547            Ordering::Equal => match self.channel_epoch.cmp(&other.channel_epoch) {
548                Ordering::Equal => self.index.cmp(&other.index),
549                Ordering::Greater => Ordering::Greater,
550                Ordering::Less => Ordering::Less,
551            },
552            Ordering::Greater => Ordering::Greater,
553            Ordering::Less => Ordering::Less,
554        }
555    }
556}
557
558impl Display for Ticket {
559    fn fmt(&self, f: &mut Formatter<'_>) -> std::fmt::Result {
560        write!(
561            f,
562            "ticket #{}, amount {}, offset {}, epoch {} in channel {}",
563            self.index, self.amount, self.index_offset, self.channel_epoch, self.channel_id
564        )
565    }
566}
567
568impl Ticket {
569    fn encode_without_signature(&self) -> [u8; Self::SIZE - Signature::SIZE] {
570        let mut ret = [0u8; Self::SIZE - Signature::SIZE];
571        let mut offset = 0;
572
573        ret[offset..offset + Hash::SIZE].copy_from_slice(self.channel_id.as_ref());
574        offset += Hash::SIZE;
575
576        // There are only 2^96 HOPR tokens
577        ret[offset..offset + 12].copy_from_slice(&self.amount.amount().to_be_bytes()[20..32]);
578        offset += 12;
579
580        // Ticket index can go only up to 2^48
581        ret[offset..offset + 6].copy_from_slice(&self.index.to_be_bytes()[2..8]);
582        offset += 6;
583
584        ret[offset..offset + 4].copy_from_slice(&self.index_offset.to_be_bytes());
585        offset += 4;
586
587        // Channel epoch can go only up to 2^24
588        ret[offset..offset + 3].copy_from_slice(&self.channel_epoch.to_be_bytes()[1..4]);
589        offset += 3;
590
591        ret[offset..offset + ENCODED_WIN_PROB_LENGTH].copy_from_slice(&self.encoded_win_prob);
592        offset += ENCODED_WIN_PROB_LENGTH;
593
594        ret[offset..offset + EthereumChallenge::SIZE].copy_from_slice(self.challenge.as_ref());
595
596        ret
597    }
598
599    /// Computes Ethereum signature hash of the ticket,
600    /// must be equal to on-chain computation
601    pub fn get_hash(&self, domain_separator: &Hash) -> Hash {
602        let ticket_hash = Hash::create(&[self.encode_without_signature().as_ref()]); // cannot fail
603        let hash_struct = Hash::create(&[&REDEEM_CALL_SELECTOR, &[0u8; 28], ticket_hash.as_ref()]);
604        Hash::create(&[&hex!("1901"), domain_separator.as_ref(), hash_struct.as_ref()])
605    }
606
607    /// Signs the ticket using the given private key, turning this ticket into [VerifiedTicket].
608    /// If a signature was already present, it will be replaced.
609    pub fn sign(mut self, signing_key: &ChainKeypair, domain_separator: &Hash) -> VerifiedTicket {
610        let ticket_hash = self.get_hash(domain_separator);
611        self.signature = Some(Signature::sign_hash(&ticket_hash, signing_key));
612        VerifiedTicket(self, ticket_hash, signing_key.public().to_address())
613    }
614
615    /// Verifies the signature of this ticket, turning this ticket into `VerifiedTicket`.
616    /// If the verification fails, `Self` is returned in the error.
617    ///
618    /// This is done by recovering the signer from the signature and verifying that it matches
619    /// the given `issuer` argument. This is possible due this specific instantiation of the ECDSA
620    /// over the secp256k1 curve.
621    /// The operation can fail if a public key cannot be recovered from the ticket signature.
622    #[instrument(level = "trace", skip_all, err)]
623    pub fn verify(self, issuer: &Address, domain_separator: &Hash) -> Result<VerifiedTicket, Box<Ticket>> {
624        let ticket_hash = self.get_hash(domain_separator);
625
626        if let Some(signature) = &self.signature {
627            match signature.recover_from_hash(&ticket_hash) {
628                Ok(pk) if pk.to_address().eq(issuer) => Ok(VerifiedTicket(self, ticket_hash, *issuer)),
629                Err(e) => {
630                    error!("failed to verify ticket signature: {e}");
631                    Err(self.into())
632                }
633                _ => Err(self.into()),
634            }
635        } else {
636            Err(self.into())
637        }
638    }
639
640    /// Returns true if this ticket aggregates multiple tickets.
641    #[inline]
642    pub fn is_aggregated(&self) -> bool {
643        // Aggregated tickets have always an index offset > 1
644        self.index_offset > 1
645    }
646
647    /// Returns the decoded winning probability of the ticket
648    #[inline]
649    pub fn win_prob(&self) -> WinningProbability {
650        WinningProbability(self.encoded_win_prob)
651    }
652}
653
654impl From<Ticket> for [u8; TICKET_SIZE] {
655    fn from(value: Ticket) -> Self {
656        let mut ret = [0u8; TICKET_SIZE];
657        ret[0..Ticket::SIZE - Signature::SIZE].copy_from_slice(value.encode_without_signature().as_ref());
658        ret[Ticket::SIZE - Signature::SIZE..].copy_from_slice(
659            value
660                .signature
661                .expect("cannot serialize ticket without signature")
662                .as_ref(),
663        );
664        ret
665    }
666}
667
668impl TryFrom<&[u8]> for Ticket {
669    type Error = GeneralError;
670
671    fn try_from(value: &[u8]) -> std::result::Result<Self, Self::Error> {
672        if value.len() == Self::SIZE {
673            let mut offset = 0;
674
675            // TODO: not necessary to the ChannelId over the wire, only the counterparty is sufficient
676            let channel_id = Hash::try_from(&value[offset..offset + Hash::SIZE])?;
677            offset += Hash::SIZE;
678
679            let mut amount = [0u8; 32];
680            amount[20..32].copy_from_slice(&value[offset..offset + 12]);
681            offset += 12;
682
683            let mut index = [0u8; 8];
684            index[2..8].copy_from_slice(&value[offset..offset + 6]);
685            offset += 6;
686
687            let mut index_offset = [0u8; 4];
688            index_offset.copy_from_slice(&value[offset..offset + 4]);
689            offset += 4;
690
691            let mut channel_epoch = [0u8; 4];
692            channel_epoch[1..4].copy_from_slice(&value[offset..offset + 3]);
693            offset += 3;
694
695            let win_prob = WinningProbability::try_from(&value[offset..offset + WinningProbability::SIZE])?;
696            offset += WinningProbability::SIZE;
697
698            debug_assert_eq!(offset, ENCODED_TICKET_LENGTH);
699
700            let challenge = EthereumChallenge::try_from(&value[offset..offset + EthereumChallenge::SIZE])?;
701            offset += EthereumChallenge::SIZE;
702
703            let signature = Signature::try_from(&value[offset..offset + Signature::SIZE])?;
704
705            // Validate the boundaries of the parsed values
706            TicketBuilder::default()
707                .channel_id(channel_id)
708                .amount(U256::from_big_endian(&amount))
709                .index(u64::from_be_bytes(index))
710                .index_offset(u32::from_be_bytes(index_offset))
711                .channel_epoch(u32::from_be_bytes(channel_epoch))
712                .win_prob(win_prob)
713                .eth_challenge(challenge)
714                .signature(signature)
715                .build()
716                .map_err(|e| GeneralError::ParseError(format!("ticket build failed: {e}")))
717        } else {
718            Err(GeneralError::ParseError("Ticket".into()))
719        }
720    }
721}
722
723const TICKET_SIZE: usize = ENCODED_TICKET_LENGTH + EthereumChallenge::SIZE + Signature::SIZE;
724
725impl BytesEncodable<TICKET_SIZE> for Ticket {}
726
727/// Holds a ticket that has been already verified.
728/// This structure guarantees that [`Ticket::get_hash()`] of [`VerifiedTicket::verified_ticket()`]
729/// is always equal to [`VerifiedTicket::verified_hash`]
730#[derive(Debug, Clone, PartialEq, Eq)]
731#[cfg_attr(feature = "serde", derive(serde::Serialize, serde::Deserialize))]
732pub struct VerifiedTicket(Ticket, Hash, Address);
733
734impl VerifiedTicket {
735    /// Returns the verified encoded winning probability of the ticket
736    #[inline]
737    pub fn win_prob(&self) -> WinningProbability {
738        self.0.win_prob()
739    }
740
741    /// Checks if this ticket is considered a win.
742    /// Requires access to the private key to compute the VRF values.
743    ///
744    /// Computes the ticket's luck value and compares it against the
745    /// ticket's probability. If luck <= probability, the ticket is
746    /// considered a win.
747    ///
748    /// ## Ticket luck value
749    /// This ticket's `luck value` is the first 7 bytes of Keccak256 hash
750    /// of the concatenation of ticket's hash, VRF's encoded `v` value,
751    /// PoR response and the ticket's signature.
752    ///
753    /// ## Winning probability
754    /// Each ticket specifies a probability, given as an integer in
755    /// [0, 2^56 - 1] where 0 -> 0% and 2^56 - 1 -> 100% win
756    /// probability. If the ticket's luck value is greater than
757    /// the stated probability, it is considered a winning ticket.
758    pub fn is_winning(&self, response: &Response, chain_keypair: &ChainKeypair, domain_separator: &Hash) -> bool {
759        if let Ok(vrf_params) = derive_vrf_parameters(self.1, chain_keypair, domain_separator.as_ref()) {
760            check_ticket_win(
761                &self.1,
762                self.0
763                    .signature
764                    .as_ref()
765                    .expect("verified ticket have always a signature"),
766                &self.0.win_prob(),
767                response,
768                &vrf_params,
769            )
770        } else {
771            error!("cannot derive vrf parameters for {self}");
772            false
773        }
774    }
775
776    /// Ticket with already verified signature.
777    #[inline]
778    pub fn verified_ticket(&self) -> &Ticket {
779        &self.0
780    }
781
782    /// Fixed ticket hash that is guaranteed to be equal to
783    /// [`Ticket::get_hash`] of [`VerifiedTicket::verified_ticket`].
784    #[inline]
785    pub fn verified_hash(&self) -> &Hash {
786        &self.1
787    }
788
789    /// Verified issuer of the ticket.
790    /// The returned address is guaranteed to be equal to the signer
791    /// recovered from the [`VerifiedTicket::verified_ticket`]'s signature.
792    #[inline]
793    pub fn verified_issuer(&self) -> &Address {
794        &self.2
795    }
796
797    /// Shorthand to retrieve reference to the verified ticket signature
798    pub fn verified_signature(&self) -> &Signature {
799        self.0
800            .signature
801            .as_ref()
802            .expect("verified ticket always has a signature")
803    }
804
805    /// Deconstructs self back into the unverified [Ticket].
806    #[inline]
807    pub fn leak(self) -> Ticket {
808        self.0
809    }
810
811    /// Creates a new unacknowledged ticket from the [VerifiedTicket],
812    /// given our own part of the PoR challenge.
813    pub fn into_unacknowledged(self, own_key: HalfKey) -> UnacknowledgedTicket {
814        UnacknowledgedTicket { ticket: self, own_key }
815    }
816
817    /// Shorthand to acknowledge the ticket if the matching response is already known.
818    /// This is used upon receiving an aggregated ticket.
819    pub fn into_acknowledged(self, response: Response) -> AcknowledgedTicket {
820        AcknowledgedTicket {
821            status: AcknowledgedTicketStatus::Untouched,
822            ticket: self,
823            response,
824        }
825    }
826}
827
828impl Display for VerifiedTicket {
829    fn fmt(&self, f: &mut Formatter<'_>) -> std::fmt::Result {
830        write!(f, "verified {}", self.0)
831    }
832}
833
834impl PartialOrd for VerifiedTicket {
835    fn partial_cmp(&self, other: &Self) -> Option<Ordering> {
836        Some(self.cmp(other))
837    }
838}
839
840impl Ord for VerifiedTicket {
841    fn cmp(&self, other: &Self) -> Ordering {
842        self.0.cmp(&other.0)
843    }
844}
845
846/// Represents a [VerifiedTicket] with an unknown other part of the [HalfKey].
847/// Once the other [HalfKey] is known (forming a [Response]),
848/// it can be [acknowledged](UnacknowledgedTicket::acknowledge).
849#[derive(Clone, Debug, PartialEq, Eq)]
850#[cfg_attr(feature = "serde", derive(serde::Serialize, serde::Deserialize))]
851pub struct UnacknowledgedTicket {
852    pub ticket: VerifiedTicket,
853    pub(crate) own_key: HalfKey,
854}
855
856impl UnacknowledgedTicket {
857    /// Convenience method to retrieve a reference to the underlying verified [Ticket].
858    #[inline]
859    pub fn verified_ticket(&self) -> &Ticket {
860        self.ticket.verified_ticket()
861    }
862
863    /// Verifies that the given acknowledgement solves this ticket's challenge and then
864    /// turns this unacknowledged ticket into an acknowledged ticket by adding
865    /// the received acknowledgement of the forwarded packet.
866    pub fn acknowledge(self, acknowledgement: &HalfKey) -> crate::errors::Result<AcknowledgedTicket> {
867        let response = Response::from_half_keys(&self.own_key, acknowledgement)?;
868        debug!(ticket = %self.ticket, response = response.to_hex(), "acknowledging ticket using response");
869
870        if self.ticket.verified_ticket().challenge == response.to_challenge()?.to_ethereum_challenge() {
871            Ok(self.ticket.into_acknowledged(response))
872        } else {
873            Err(CryptoError::InvalidChallenge.into())
874        }
875    }
876}
877
878/// Status of the acknowledged ticket.
879#[repr(u8)]
880#[derive(
881    Clone,
882    Copy,
883    Debug,
884    Default,
885    Eq,
886    PartialEq,
887    strum::Display,
888    strum::EnumString,
889    num_enum::IntoPrimitive,
890    num_enum::TryFromPrimitive,
891)]
892#[cfg_attr(feature = "serde", derive(serde::Serialize, serde::Deserialize))]
893#[strum(serialize_all = "PascalCase")]
894pub enum AcknowledgedTicketStatus {
895    /// The ticket is available for redeeming or aggregating
896    #[default]
897    Untouched = 0,
898    /// Ticket is currently being redeemed in and ongoing redemption process
899    BeingRedeemed = 1,
900    /// Ticket is currently being aggregated in and ongoing aggregation process
901    BeingAggregated = 2,
902}
903
904/// Contains acknowledgment information and the respective ticket
905#[derive(Clone, Debug, PartialEq, Eq)]
906#[cfg_attr(feature = "serde", derive(serde::Serialize, serde::Deserialize))]
907pub struct AcknowledgedTicket {
908    #[cfg_attr(feature = "serde", serde(default))]
909    pub status: AcknowledgedTicketStatus,
910    pub ticket: VerifiedTicket,
911    pub response: Response,
912}
913
914impl PartialOrd for AcknowledgedTicket {
915    fn partial_cmp(&self, other: &Self) -> Option<std::cmp::Ordering> {
916        Some(self.cmp(other))
917    }
918}
919
920impl Ord for AcknowledgedTicket {
921    fn cmp(&self, other: &Self) -> std::cmp::Ordering {
922        self.ticket.cmp(&other.ticket)
923    }
924}
925
926impl AcknowledgedTicket {
927    /// Convenience method to retrieve a reference to the underlying verified [Ticket].
928    #[inline]
929    pub fn verified_ticket(&self) -> &Ticket {
930        self.ticket.verified_ticket()
931    }
932
933    /// Checks if this acknowledged ticket is winning.
934    pub fn is_winning(&self, chain_keypair: &ChainKeypair, domain_separator: &Hash) -> bool {
935        self.ticket.is_winning(&self.response, chain_keypair, domain_separator)
936    }
937
938    /// Transforms this ticket into [RedeemableTicket] that can be redeemed on-chain
939    /// or transformed into [TransferableWinningTicket] that can be sent for aggregation.
940    /// The `chain_keypair` must not be of the ticket's issuer.
941    pub fn into_redeemable(
942        self,
943        chain_keypair: &ChainKeypair,
944        domain_separator: &Hash,
945    ) -> crate::errors::Result<RedeemableTicket> {
946        // This function must be called by the ticket recipient and not the issuer
947        if chain_keypair.public().to_address().eq(self.ticket.verified_issuer()) {
948            return Err(errors::CoreTypesError::LoopbackTicket);
949        }
950
951        let vrf_params = derive_vrf_parameters(self.ticket.verified_hash(), chain_keypair, domain_separator.as_ref())?;
952
953        Ok(RedeemableTicket {
954            ticket: self.ticket,
955            response: self.response,
956            vrf_params,
957            channel_dst: *domain_separator,
958        })
959    }
960
961    /// Shorthand for transforming this ticket into [TransferableWinningTicket].
962    /// See [`AcknowledgedTicket::into_redeemable`] for details.
963    pub fn into_transferable(
964        self,
965        chain_keypair: &ChainKeypair,
966        domain_separator: &Hash,
967    ) -> errors::Result<TransferableWinningTicket> {
968        self.into_redeemable(chain_keypair, domain_separator)
969            .map(TransferableWinningTicket::from)
970    }
971}
972
973impl Display for AcknowledgedTicket {
974    fn fmt(&self, f: &mut Formatter<'_>) -> std::fmt::Result {
975        write!(f, "acknowledged {} in state '{}'", self.ticket, self.status)
976    }
977}
978
979/// Represents a winning ticket that can be successfully redeemed on-chain.
980#[derive(Clone, Debug)]
981#[cfg_attr(feature = "serde", derive(serde::Serialize, serde::Deserialize))]
982pub struct RedeemableTicket {
983    /// Verified ticket that can be redeemed.
984    pub ticket: VerifiedTicket,
985    /// Solution to the PoR challenge in the ticket.
986    pub response: Response,
987    /// VRF parameters required for redeeming.
988    pub vrf_params: VrfParameters,
989    /// Channel domain separator used to compute the VRF parameters.
990    pub channel_dst: Hash,
991}
992
993impl RedeemableTicket {
994    /// Convenience method to retrieve a reference to the underlying verified [Ticket].
995    #[inline]
996    pub fn verified_ticket(&self) -> &Ticket {
997        self.ticket.verified_ticket()
998    }
999}
1000
1001impl PartialEq for RedeemableTicket {
1002    fn eq(&self, other: &Self) -> bool {
1003        self.ticket == other.ticket && self.channel_dst == other.channel_dst && self.response == other.response
1004    }
1005}
1006
1007impl Display for RedeemableTicket {
1008    fn fmt(&self, f: &mut Formatter<'_>) -> std::fmt::Result {
1009        write!(f, "redeemable {}", self.ticket)
1010    }
1011}
1012
1013impl From<RedeemableTicket> for AcknowledgedTicket {
1014    fn from(value: RedeemableTicket) -> Self {
1015        Self {
1016            status: AcknowledgedTicketStatus::Untouched,
1017            ticket: value.ticket,
1018            response: value.response,
1019        }
1020    }
1021}
1022
1023/// Represents a ticket that could be transferred over the wire
1024/// and independently verified again by the other party.
1025///
1026/// The [TransferableWinningTicket] can be easily retrieved from [RedeemableTicket], which strips
1027/// information about verification.
1028/// [TransferableWinningTicket] can be attempted to be converted back to [RedeemableTicket] only
1029/// when verified via [`TransferableWinningTicket::into_redeemable`] again.
1030#[derive(Debug, Clone)]
1031#[cfg_attr(feature = "serde", derive(serde::Serialize, serde::Deserialize))]
1032pub struct TransferableWinningTicket {
1033    pub ticket: Ticket,
1034    pub response: Response,
1035    pub vrf_params: VrfParameters,
1036    pub signer: Address,
1037}
1038
1039impl TransferableWinningTicket {
1040    /// Attempts to transform this ticket back into a [RedeemableTicket].
1041    ///
1042    /// Verifies that the `signer` matches the `expected_issuer` and that the
1043    /// ticket has a valid signature from the `signer`.
1044    /// Then it verifies if the ticket is winning and therefore if it can be successfully
1045    /// redeemed on-chain.
1046    pub fn into_redeemable(
1047        self,
1048        expected_issuer: &Address,
1049        domain_separator: &Hash,
1050    ) -> errors::Result<RedeemableTicket> {
1051        if !self.signer.eq(expected_issuer) {
1052            return Err(crate::errors::CoreTypesError::InvalidInputData(
1053                "invalid ticket issuer".into(),
1054            ));
1055        }
1056
1057        let verified_ticket = self
1058            .ticket
1059            .verify(&self.signer, domain_separator)
1060            .map_err(|_| CoreTypesError::CryptoError(CryptoError::SignatureVerification))?;
1061
1062        if check_ticket_win(
1063            verified_ticket.verified_hash(),
1064            verified_ticket.verified_signature(),
1065            &verified_ticket.verified_ticket().win_prob(),
1066            &self.response,
1067            &self.vrf_params,
1068        ) {
1069            Ok(RedeemableTicket {
1070                ticket: verified_ticket,
1071                response: self.response,
1072                vrf_params: self.vrf_params,
1073                channel_dst: *domain_separator,
1074            })
1075        } else {
1076            Err(crate::errors::CoreTypesError::InvalidInputData(
1077                "ticket is not a win".into(),
1078            ))
1079        }
1080    }
1081}
1082
1083impl PartialEq for TransferableWinningTicket {
1084    fn eq(&self, other: &Self) -> bool {
1085        self.ticket == other.ticket && self.signer == other.signer && self.response == other.response
1086    }
1087}
1088
1089impl PartialOrd<Self> for TransferableWinningTicket {
1090    fn partial_cmp(&self, other: &Self) -> Option<Ordering> {
1091        Some(self.ticket.cmp(&other.ticket))
1092    }
1093}
1094
1095impl From<RedeemableTicket> for TransferableWinningTicket {
1096    fn from(value: RedeemableTicket) -> Self {
1097        Self {
1098            response: value.response,
1099            vrf_params: value.vrf_params,
1100            signer: *value.ticket.verified_issuer(),
1101            ticket: value.ticket.leak(),
1102        }
1103    }
1104}
1105
1106#[cfg(test)]
1107pub mod tests {
1108    use hex_literal::hex;
1109    use hopr_crypto_random::Randomizable;
1110    use hopr_crypto_types::{
1111        keypairs::{ChainKeypair, Keypair},
1112        types::{HalfKey, Hash, Response},
1113    };
1114    use hopr_primitive_types::{
1115        prelude::UnitaryFloatOps,
1116        primitives::{Address, EthereumChallenge, U256},
1117    };
1118
1119    use super::*;
1120
1121    lazy_static::lazy_static! {
1122        static ref ALICE: ChainKeypair = ChainKeypair::from_secret(&hex!("492057cf93e99b31d2a85bc5e98a9c3aa0021feec52c227cc8170e8f7d047775")).expect("lazy static keypair should be constructible");
1123        static ref BOB: ChainKeypair = ChainKeypair::from_secret(&hex!("48680484c6fc31bc881a0083e6e32b6dc789f9eaba0f8b981429fd346c697f8c")).expect("lazy static keypair should be constructible");
1124    }
1125
1126    #[cfg(feature = "serde")]
1127    const BINCODE_CONFIGURATION: bincode::config::Configuration = bincode::config::standard()
1128        .with_little_endian()
1129        .with_variable_int_encoding();
1130
1131    #[test]
1132    pub fn test_win_prob_to_f64() -> anyhow::Result<()> {
1133        assert_eq!(0.0f64, WinningProbability::NEVER.as_f64());
1134
1135        assert_eq!(1.0f64, WinningProbability::ALWAYS.as_f64());
1136
1137        let mut test_bit_string = [0xffu8; 7];
1138        test_bit_string[0] = 0x7f;
1139        assert_eq!(0.5f64, WinningProbability::from(&test_bit_string).as_f64());
1140
1141        test_bit_string[0] = 0x3f;
1142        assert_eq!(0.25f64, WinningProbability::from(&test_bit_string).as_f64());
1143
1144        test_bit_string[0] = 0x1f;
1145        assert_eq!(0.125f64, WinningProbability::from(&test_bit_string).as_f64());
1146
1147        Ok(())
1148    }
1149
1150    #[test]
1151    pub fn test_f64_to_win_prob() -> anyhow::Result<()> {
1152        assert_eq!([0u8; 7], WinningProbability::try_from(0.0f64)?.as_encoded());
1153
1154        let mut test_bit_string = [0xffu8; 7];
1155        assert_eq!(test_bit_string, WinningProbability::try_from(1.0f64)?.as_encoded());
1156
1157        test_bit_string[0] = 0x7f;
1158        assert_eq!(test_bit_string, WinningProbability::try_from(0.5f64)?.as_encoded());
1159
1160        test_bit_string[0] = 0x3f;
1161        assert_eq!(test_bit_string, WinningProbability::try_from(0.25f64)?.as_encoded());
1162
1163        test_bit_string[0] = 0x1f;
1164        assert_eq!(test_bit_string, WinningProbability::try_from(0.125f64)?.as_encoded());
1165
1166        Ok(())
1167    }
1168
1169    #[test]
1170    pub fn test_win_prob_approx_eq() -> anyhow::Result<()> {
1171        let wp_0 = WinningProbability(hex!("0020C49BBFFFFF"));
1172        let wp_1 = WinningProbability(hex!("0020C49BA5E34F"));
1173
1174        assert_ne!(wp_0.as_ref(), wp_1.as_ref());
1175        assert_eq!(wp_0, wp_1.as_f64());
1176
1177        Ok(())
1178    }
1179
1180    #[test]
1181    pub fn test_win_prob_back_and_forth() -> anyhow::Result<()> {
1182        for float in [0.1f64, 0.002f64, 0.00001f64, 0.7311111f64, 1.0f64, 0.0f64] {
1183            assert!((float - WinningProbability::try_from_f64(float)?.as_f64()).abs() < f64::EPSILON);
1184        }
1185
1186        Ok(())
1187    }
1188
1189    #[test]
1190    pub fn test_win_prob_must_be_correctly_ordered() {
1191        let increment = WinningProbability::EPSILON * 100.0; // Testing the entire range would take too long
1192        let mut prev = WinningProbability::NEVER;
1193        while let Ok(next) = WinningProbability::try_from_f64(prev.as_f64() + increment) {
1194            assert!(prev.approx_cmp(&next).is_lt());
1195            prev = next;
1196        }
1197    }
1198
1199    #[test]
1200    pub fn test_win_prob_epsilon_must_be_never() -> anyhow::Result<()> {
1201        assert!(WinningProbability::NEVER.approx_eq(&WinningProbability::try_from_f64(WinningProbability::EPSILON)?));
1202        Ok(())
1203    }
1204
1205    #[test]
1206    pub fn test_win_prob_bounds_must_be_eq() -> anyhow::Result<()> {
1207        let bound = 0.1 + WinningProbability::EPSILON;
1208        let other = 0.1;
1209        assert!(WinningProbability::try_from_f64(bound)?.approx_eq(&WinningProbability::try_from_f64(other)?));
1210        Ok(())
1211    }
1212
1213    #[test]
1214    pub fn test_ticket_builder_zero_hop() -> anyhow::Result<()> {
1215        let ticket = TicketBuilder::zero_hop()
1216            .direction(&ALICE.public().to_address(), &BOB.public().to_address())
1217            .eth_challenge(Default::default())
1218            .build()?;
1219        assert_eq!(0, ticket.index);
1220        assert_eq!(0.0, ticket.win_prob().as_f64());
1221        assert_eq!(0, ticket.channel_epoch);
1222        assert_eq!(
1223            generate_channel_id(&ALICE.public().to_address(), &BOB.public().to_address()),
1224            ticket.channel_id
1225        );
1226        Ok(())
1227    }
1228
1229    #[test]
1230    pub fn test_ticket_serialize_deserialize() -> anyhow::Result<()> {
1231        let initial_ticket = TicketBuilder::default()
1232            .direction(&ALICE.public().to_address(), &BOB.public().to_address())
1233            .balance(1.into())
1234            .index(0)
1235            .index_offset(1)
1236            .win_prob(1.0.try_into()?)
1237            .channel_epoch(1)
1238            .eth_challenge(Default::default())
1239            .build_signed(&ALICE, &Default::default())?;
1240
1241        assert_ne!(initial_ticket.verified_hash().as_ref(), [0u8; Hash::SIZE]);
1242
1243        let ticket_bytes: [u8; Ticket::SIZE] = initial_ticket.verified_ticket().clone().into();
1244        assert_eq!(
1245            initial_ticket.verified_ticket(),
1246            &Ticket::try_from(ticket_bytes.as_ref())?
1247        );
1248        Ok(())
1249    }
1250
1251    #[test]
1252    #[cfg(feature = "serde")]
1253    pub fn test_ticket_serialize_deserialize_serde() -> anyhow::Result<()> {
1254        let initial_ticket = TicketBuilder::default()
1255            .direction(&ALICE.public().to_address(), &BOB.public().to_address())
1256            .balance(1.into())
1257            .index(0)
1258            .index_offset(1)
1259            .win_prob(1.0.try_into()?)
1260            .channel_epoch(1)
1261            .eth_challenge(Default::default())
1262            .build_signed(&ALICE, &Default::default())?;
1263
1264        assert_eq!(
1265            initial_ticket,
1266            bincode::serde::decode_from_slice(
1267                &bincode::serde::encode_to_vec(&initial_ticket, BINCODE_CONFIGURATION)?,
1268                BINCODE_CONFIGURATION
1269            )
1270            .map(|v| v.0)?
1271        );
1272        Ok(())
1273    }
1274
1275    #[test]
1276    pub fn test_ticket_sign_verify() -> anyhow::Result<()> {
1277        let initial_ticket = TicketBuilder::default()
1278            .direction(&ALICE.public().to_address(), &BOB.public().to_address())
1279            .balance(1.into())
1280            .index(0)
1281            .index_offset(1)
1282            .win_prob(1.0.try_into()?)
1283            .channel_epoch(1)
1284            .eth_challenge(Default::default())
1285            .build_signed(&ALICE, &Default::default())?;
1286
1287        assert_ne!(initial_ticket.verified_hash().as_ref(), [0u8; Hash::SIZE]);
1288
1289        let ticket = initial_ticket.leak();
1290        assert!(ticket.verify(&ALICE.public().to_address(), &Default::default()).is_ok());
1291        Ok(())
1292    }
1293
1294    #[test]
1295    pub fn test_zero_hop() -> anyhow::Result<()> {
1296        let ticket = TicketBuilder::zero_hop()
1297            .direction(&ALICE.public().to_address(), &BOB.public().to_address())
1298            .eth_challenge(Default::default())
1299            .build_signed(&ALICE, &Default::default())?;
1300
1301        assert!(
1302            ticket
1303                .leak()
1304                .verify(&ALICE.public().to_address(), &Hash::default())
1305                .is_ok()
1306        );
1307        Ok(())
1308    }
1309
1310    fn mock_ticket(
1311        pk: &ChainKeypair,
1312        counterparty: &Address,
1313        domain_separator: Option<Hash>,
1314        challenge: Option<EthereumChallenge>,
1315    ) -> anyhow::Result<VerifiedTicket> {
1316        let win_prob = 1.0f64; // 100 %
1317        let price_per_packet: U256 = 10000000000000000u128.into(); // 0.01 HOPR
1318        let path_pos = 5u64;
1319
1320        Ok(TicketBuilder::default()
1321            .direction(&pk.public().to_address(), counterparty)
1322            .amount(price_per_packet.div_f64(win_prob)? * U256::from(path_pos))
1323            .index(0)
1324            .index_offset(1)
1325            .win_prob(1.0.try_into()?)
1326            .channel_epoch(4)
1327            .eth_challenge(challenge.unwrap_or_default())
1328            .build_signed(pk, &domain_separator.unwrap_or_default())?)
1329    }
1330
1331    #[test]
1332    fn test_unacknowledged_ticket_challenge_response() -> anyhow::Result<()> {
1333        let hk1 = HalfKey::try_from(hex!("3477d7de923ba3a7d5d72a7d6c43fd78395453532d03b2a1e2b9a7cc9b61bafa").as_ref())?;
1334
1335        let hk2 = HalfKey::try_from(hex!("4471496ef88d9a7d86a92b7676f3c8871a60792a37fae6fc3abc347c3aa3b16b").as_ref())?;
1336
1337        let challenge = Response::from_half_keys(&hk1, &hk2)?.to_challenge()?;
1338
1339        let dst = Hash::default();
1340        let ack = mock_ticket(
1341            &ALICE,
1342            &BOB.public().to_address(),
1343            Some(dst),
1344            Some(challenge.to_ethereum_challenge()),
1345        )?
1346        .into_unacknowledged(hk1)
1347        .acknowledge(&hk2)?;
1348
1349        assert!(ack.is_winning(&BOB, &dst), "ticket must be winning");
1350        Ok(())
1351    }
1352
1353    #[test]
1354    #[cfg(feature = "serde")]
1355    fn test_acknowledged_ticket_serde() -> anyhow::Result<()> {
1356        let response =
1357            Response::try_from(hex!("876a41ee5fb2d27ac14d8e8d552692149627c2f52330ba066f9e549aef762f73").as_ref())?;
1358
1359        let dst = Hash::default();
1360
1361        let ticket = mock_ticket(
1362            &ALICE,
1363            &BOB.public().to_address(),
1364            Some(dst),
1365            Some(response.to_challenge()?.to_ethereum_challenge()),
1366        )?;
1367
1368        let acked_ticket = ticket.into_acknowledged(response);
1369
1370        let mut deserialized_ticket = bincode::serde::decode_from_slice(
1371            &bincode::serde::encode_to_vec(&acked_ticket, BINCODE_CONFIGURATION)?,
1372            BINCODE_CONFIGURATION,
1373        )
1374        .map(|v| v.0)?;
1375        assert_eq!(acked_ticket, deserialized_ticket);
1376
1377        assert!(deserialized_ticket.is_winning(&BOB, &dst));
1378
1379        deserialized_ticket.status = super::AcknowledgedTicketStatus::BeingAggregated;
1380
1381        assert_eq!(
1382            deserialized_ticket,
1383            bincode::serde::decode_from_slice(
1384                &bincode::serde::encode_to_vec(&deserialized_ticket, BINCODE_CONFIGURATION)?,
1385                BINCODE_CONFIGURATION,
1386            )
1387            .map(|v| v.0)?
1388        );
1389        Ok(())
1390    }
1391
1392    #[test]
1393    fn test_ticket_entire_ticket_transfer_flow() -> anyhow::Result<()> {
1394        let hk1 = HalfKey::random();
1395        let hk2 = HalfKey::random();
1396        let resp = Response::from_half_keys(&hk1, &hk2)?;
1397
1398        let verified = TicketBuilder::default()
1399            .direction(&ALICE.public().to_address(), &BOB.public().to_address())
1400            .balance(1.into())
1401            .index(0)
1402            .index_offset(1)
1403            .win_prob(1.0.try_into()?)
1404            .channel_epoch(1)
1405            .challenge(resp.to_challenge()?)
1406            .build_signed(&ALICE, &Default::default())?;
1407
1408        let unack = verified.into_unacknowledged(hk1);
1409        let acknowledged = unack.acknowledge(&hk2).expect("should acknowledge");
1410
1411        let redeemable_1 = acknowledged.clone().into_redeemable(&BOB, &Hash::default())?;
1412
1413        let transferable = acknowledged.into_transferable(&BOB, &Hash::default())?;
1414
1415        let redeemable_2 = transferable.into_redeemable(&ALICE.public().to_address(), &Hash::default())?;
1416
1417        assert_eq!(redeemable_1, redeemable_2);
1418        assert_eq!(redeemable_1.vrf_params.V, redeemable_2.vrf_params.V);
1419        Ok(())
1420    }
1421}
hopr_internal_types/tickets.rs

hopr_internal_types/
tickets.rs
