xray-tui 1.4.1

A layer inspector for OCI-compliant images
Documentation 
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

//! Contains all the stuff related to parsing JSON blobs.

use std::io::Read;

use anyhow::Context;
use serde::de::Visitor;
use serde::{Deserialize, Deserializer};

use super::Sha256Digest;
use crate::parser::constants::{SHA256_DIGEST_LENGTH, SHA256_DIGEST_PREFIX};
use crate::parser::util::sha256_digest_from_hex;

pub(super) type ImageLayerConfigs = Vec<LayerConfig>;
pub(super) type ImageHistory = Vec<HistoryEntry>;

/// Docker-specific manifest that can be found in the root of an image.
///
/// In in our case, it's used to extract the image name and tag, but it's not guaranteed to be present in an image,
/// especially when using non-Docker container runtimes.
#[derive(Deserialize)]
pub(super) struct DockerManifest {
    #[serde(rename = "RepoTags")]
    repo_tags: Option<Vec<String>>,
}

impl DockerManifest {
    pub fn from_reader(src: impl Read) -> anyhow::Result<Option<String>> {
        let mut manifest =
            // Docker manifest contains an array of manifest objects, so we need a vec here
            serde_json::from_reader::<_, Vec<DockerManifest>>(src).context("failed to parse the Docker's manifest")?;

        Ok(manifest.get_mut(0).and_then(|manifest| {
            manifest.repo_tags.as_mut().and_then(|tags| tags.pop())
        }))
    }
}

/// Represents known JSON files that can be encountered when parsing an OCI-compliant image.
#[derive(Debug, Deserialize)]
#[serde(untagged)]
pub(super) enum JsonBlob {
    /// Image Index.
    ///
    /// Source: [OCI Image Index Specification](https://github.com/opencontainers/image-spec/blob/main/image-index.md)
    Index { manifests: Vec<ImageIndexManifest> },
    /// Image Manifest.
    ///
    /// Source: [OCI Image Manifest Specification](https://github.com/opencontainers/image-spec/blob/main/manifest.md).
    Manifest { layers: ImageLayerConfigs },
    /// Image Config.
    ///
    /// Sourcce: [OCI Image Configuration](https://github.com/opencontainers/image-spec/blob/main/config.md)
    Config {
        architecture: String,
        os: String,
        history: ImageHistory,
    },
}

/// Represents a subset of fields of a single entry in the `history` array that can be found in an OCI Image Config.
///
/// Source: [OCI Image Configuration](https://github.com/opencontainers/image-spec/blob/main/config.md#properties)
#[derive(Debug, Deserialize)]
pub(super) struct HistoryEntry {
    pub created_by: String,
    pub comment: Option<String>,
    #[serde(default)]
    pub empty_layer: bool,
}

/// Represents a subset of fields of a single entry in the `layers` array that can be found in an OCI Image Manifest.
///
/// Source: [OCI Image Manifest Specification](https://github.com/opencontainers/image-spec/blob/main/manifest.md#image-manifest-property-descriptions)
#[derive(Debug, Deserialize)]
pub(super) struct LayerConfig {
    #[serde(deserialize_with = "deserialize_sha256_digest")]
    pub digest: Sha256Digest,
}

/// Deserializes a hex string with SHA256 digest that is prepended with the `sha256:` prefix.
fn deserialize_sha256_digest<'de, D>(de: D) -> Result<Sha256Digest, D::Error>
where
    D: Deserializer<'de>,
{
    struct Sha256HashVisitor;

    impl Visitor<'_> for Sha256HashVisitor {
        type Value = Sha256Digest;

        fn expecting(
            &self,
            formatter: &mut std::fmt::Formatter,
        ) -> std::fmt::Result {
            formatter
                .write_str("a sha256 digest string prefixed with `sha256:`")
        }

        fn visit_str<E>(self, v: &str) -> Result<Self::Value, E>
        where
            E: serde::de::Error,
        {
            // Strip the `sha256:` prefix
            let raw = &v[SHA256_DIGEST_PREFIX.len()..];

            // multiply by 2 because we are dealing with a hex str
            if raw.len() != SHA256_DIGEST_LENGTH * 2 {
                return Err(serde::de::Error::custom(
                    "Invalid sha256 digest format",
                ));
            }

            sha256_digest_from_hex(raw).map_err(|_| {
                serde::de::Error::custom("Failed to parse the sha256 digest")
            })
        }
    }

    de.deserialize_str(Sha256HashVisitor)
}

/// Represents a subset of fields of a single manifest that can be found in the Image Index.
#[derive(Debug, Deserialize)]
pub(super) struct ImageIndexManifest {
    /// Source: [Annotations](https://github.com/opencontainers/image-spec/blob/main/annotations.md).
    pub annotations: Option<ImageIndexManifestAnnotations>,
}

/// A set of well-known annotation keys.
///
/// Source: [Pre-Defined Annotation Keys](https://github.com/opencontainers/image-spec/blob/main/annotations.md#pre-defined-annotation-keys)
#[derive(Debug, Deserialize)]
pub(super) struct ImageIndexManifestAnnotations {
    /// Fully qualified image name.
    #[serde(rename = "io.containerd.image.name")]
    pub fully_qualified_image_name: Option<String>,
}