drogue-tls 0.6.0

TLS 1.3 client with no_std support and no allocator
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

use crate::config::{Certificate, TlsCipherSuite, TlsConfig};
use crate::handshake::{
    certificate::{CertificateEntryRef, CertificateRef as ServerCertificate},
    certificate_verify::CertificateVerify,
};
use crate::TlsError;
use core::convert::TryFrom;
use core::convert::TryInto;
use webpki::DnsNameRef;

static ALL_SIGALGS: &[&webpki::SignatureAlgorithm] = &[
    &webpki::ECDSA_P256_SHA256,
    &webpki::ECDSA_P256_SHA384,
    &webpki::ECDSA_P384_SHA256,
    &webpki::ECDSA_P384_SHA384,
    &webpki::ED25519,
];

pub(crate) fn verify_signature<'a, CipherSuite>(
    config: &TlsConfig<'a, CipherSuite>,
    message: &[u8],
    certificate: ServerCertificate,
    verify: CertificateVerify,
) -> Result<(), TlsError>
where
    CipherSuite: TlsCipherSuite + 'static,
{
    let mut verified = false;
    if config.verify_cert {
        if !certificate.entries.is_empty() {
            // TODO: Support intermediates...
            if let CertificateEntryRef::X509(certificate) = certificate.entries[0] {
                let cert = webpki::EndEntityCert::try_from(certificate).map_err(|e| {
                    warn!("Error loading cert: {:?}", e);
                    TlsError::DecodeError
                })?;

                trace!(
                    "Verifying with signature scheme {:?}",
                    verify.signature_scheme
                );
                info!("Signature: {:x?}", verify.signature);
                let pkisig = verify.signature_scheme.try_into()?;
                match cert.verify_signature(pkisig, message, verify.signature) {
                    Ok(_) => {
                        verified = true;
                    }
                    Err(e) => {
                        info!("Error verifying signature: {:?}", e);
                    }
                }
            }
        }
    }
    if !verified && config.verify_cert {
        return Err(TlsError::InvalidSignature);
    }
    Ok(())
}

pub(crate) fn verify_certificate<'a, CipherSuite>(
    config: &TlsConfig<'a, CipherSuite>,
    certificate: &ServerCertificate,
    now: Option<u64>,
) -> Result<(), TlsError>
where
    CipherSuite: TlsCipherSuite + 'static,
{
    let mut verified = false;
    let mut host_verified = false;
    if config.verify_cert {
        if let Some(Certificate::X509(ca)) = config.ca {
            let trust = webpki::TrustAnchor::try_from_cert_der(ca).map_err(|e| {
                warn!("Error loading CA: {:?}", e);
                TlsError::DecodeError
            })?;
            let anchors = &[trust];
            let anchors = webpki::TLSServerTrustAnchors(anchors);

            trace!("We got {} certificate entries", certificate.entries.len());

            if !certificate.entries.is_empty() {
                // TODO: Support intermediates...
                if let CertificateEntryRef::X509(certificate) = certificate.entries[0] {
                    let cert = webpki::EndEntityCert::try_from(certificate).map_err(|e| {
                        warn!("Error loading cert: {:?}", e);
                        TlsError::DecodeError
                    })?;

                    let time = if let Some(now) = now {
                        webpki::Time::from_seconds_since_unix_epoch(now)
                    } else {
                        // If no clock is provided, use certificate notAfter as the timestamp, if available
                        if let Ok(validity) = cert.validity() {
                            validity.not_after
                        } else {
                            webpki::Time::from_seconds_since_unix_epoch(0)
                        }
                    };
                    info!("Certificate is loaded!");
                    match cert.verify_is_valid_tls_server_cert(ALL_SIGALGS, &anchors, &[], time) {
                        Ok(_) => verified = true,
                        Err(e) => {
                            warn!("Error verifying certificate: {:?}", e);
                        }
                    }

                    if config.verify_host && config.server_name.is_some() {
                        match cert.verify_is_valid_for_dns_name(
                            DnsNameRef::try_from_ascii_str(config.server_name.unwrap()).unwrap(),
                        ) {
                            Ok(_) => host_verified = true,
                            Err(e) => {
                                warn!("Error verifying host: {:?}", e);
                            }
                        }
                    }
                }
            }
        }
    } else {
        // Disable host verification if cert verification is disabled
        host_verified = true;
    }
    if !verified && config.verify_cert {
        return Err(TlsError::InvalidCertificate);
    }

    if !host_verified && config.verify_host {
        return Err(TlsError::InvalidCertificate);
    }
    Ok(())
}