1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160

// Copyright (C) 2019-2022 Aleo Systems Inc.
// This file is part of the snarkVM library.

// The snarkVM library is free software: you can redistribute it and/or modify
// it under the terms of the GNU General Public License as published by
// the Free Software Foundation, either version 3 of the License, or
// (at your option) any later version.

// The snarkVM library is distributed in the hope that it will be useful,
// but WITHOUT ANY WARRANTY; without even the implied warranty of
// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
// GNU General Public License for more details.

// You should have received a copy of the GNU General Public License
// along with the snarkVM library. If not, see <https://www.gnu.org/licenses/>.

/// The error type for `PolynomialCommitment`.
#[derive(Debug)]
pub enum PCError {
    AnyhowError(anyhow::Error),

    /// The query set contains a label for a polynomial that was not provided as
    /// input to the `PC::open`.
    MissingPolynomial {
        /// The label of the missing polynomial.
        label: String,
    },

    /// `Evaluations` does not contain an evaluation for the polynomial labelled
    /// `label` at a particular query.
    MissingEvaluation {
        /// The label of the missing polynomial.
        label: String,
    },

    /// The provided polynomial was meant to be hiding, but `rng` was `None`.
    MissingRng,

    /// The degree provided in setup was too small; degree 0 polynomials
    /// are not supported.
    DegreeIsZero,

    /// The degree of the polynomial passed to `commit` or `open`
    /// was too large.
    TooManyCoefficients {
        /// The number of coefficients in the polynomial.
        num_coefficients: usize,
        /// The maximum number of powers provided in `Powers`.
        num_powers: usize,
    },

    /// The hiding bound was not `None`, but the hiding bound was zero.
    HidingBoundIsZero,

    /// The hiding bound was too large for the given `Powers`.
    HidingBoundToolarge {
        /// The hiding bound
        hiding_poly_degree: usize,
        /// The number of powers.
        num_powers: usize,
    },

    /// The lagrange basis is not a power of two.
    LagrangeBasisSizeIsNotPowerOfTwo,

    /// The lagrange basis is larger than the supported degree,
    LagrangeBasisSizeIsTooLarge,

    /// The degree provided to `trim` was too large.
    TrimmingDegreeTooLarge,

    /// The provided equation contained multiple polynomials, of which least one
    /// had a strict degree bound.
    EquationHasDegreeBounds(String),

    /// The required degree bound is not supported by ck/vk
    UnsupportedDegreeBound(usize),

    /// The provided equation contained multiple polynomials, of which least one
    /// had a strict degree bound.
    UnsupportedLagrangeBasisSize(usize),

    /// The degree bound for the `index`-th polynomial passed to `commit`, `open`
    /// or `check` was incorrect, that is, `degree_bound >= poly_degree` or
    /// `degree_bound <= max_degree`.
    IncorrectDegreeBound {
        /// Degree of the polynomial.
        poly_degree: usize,
        /// Degree bound.
        degree_bound: usize,
        /// Maximum supported degree.
        supported_degree: usize,
        /// Index of the offending polynomial.
        label: String,
    },

    Terminated,
}

impl snarkvm_utilities::error::Error for PCError {}

impl From<anyhow::Error> for PCError {
    fn from(other: anyhow::Error) -> Self {
        Self::AnyhowError(other)
    }
}

impl core::fmt::Display for PCError {
    fn fmt(&self, f: &mut core::fmt::Formatter<'_>) -> core::fmt::Result {
        match self {
            Self::AnyhowError(error) => write!(f, "{error}"),
            Self::MissingPolynomial { label } => {
                write!(f, "`QuerySet` refers to polynomial \"{}\", but it was not provided.", label)
            }
            Self::MissingEvaluation { label } => write!(
                f,
                "`QuerySet` refers to polynomial \"{}\", but `Evaluations` does not contain an evaluation for it.",
                label
            ),
            Self::MissingRng => write!(f, "hiding commitments require `Some(rng)`"),
            Self::DegreeIsZero => write!(f, "this scheme does not support committing to degree 0 polynomials"),
            Self::TooManyCoefficients { num_coefficients, num_powers } => write!(
                f,
                "the number of coefficients in the polynomial ({:?}) is greater than\
                 the maximum number of powers in `Powers` ({:?})",
                num_coefficients, num_powers
            ),
            Self::HidingBoundIsZero => write!(f, "this scheme does not support non-`None` hiding bounds that are 0"),
            Self::HidingBoundToolarge { hiding_poly_degree, num_powers } => write!(
                f,
                "the degree of the hiding poly ({:?}) is not less than the maximum number of powers in `Powers` ({:?})",
                hiding_poly_degree, num_powers
            ),
            Self::TrimmingDegreeTooLarge => write!(f, "the degree provided to `trim` was too large"),
            Self::EquationHasDegreeBounds(e) => {
                write!(f, "the eqaution \"{}\" contained degree-bounded polynomials", e)
            }
            Self::UnsupportedDegreeBound(bound) => {
                write!(f, "the degree bound ({:?}) is not supported by the parameters", bound)
            }
            Self::LagrangeBasisSizeIsNotPowerOfTwo => {
                write!(f, "the Lagrange Basis size is not a power of two")
            }
            Self::UnsupportedLagrangeBasisSize(size) => {
                write!(f, "the Lagrange basis size ({:?}) is not supported by the parameters", size)
            }
            Self::LagrangeBasisSizeIsTooLarge => {
                write!(f, "the Lagrange Basis size larger than max supported degree")
            }
            Self::IncorrectDegreeBound { poly_degree, degree_bound, supported_degree, label } => write!(
                f,
                "the degree bound ({:?}) for the polynomial {} \
                 (having degree {:?}) is greater than the maximum \
                 supported degree ({:?})",
                degree_bound, label, poly_degree, supported_degree
            ),
            Self::Terminated => write!(f, "terminated"),
        }
    }
}