gnutls_certificate_set_verify_limits - Linux
Overview
gnutls_certificate_set_verify_limits
manipulates certificate verification limits, specifically regarding path length, key usage, and constraints. This command is crucial for ensuring the validity and authenticity of certificates within the context of TLS/SSL communication.
Syntax
gnutls_certificate_set_verify_limits(certificate, depth, key_usage, key_usage_critical, extension_critical)
Options/Flags
certificate
: Pointer to the X.509 certificate to be verified.depth
: Maximum allowed depth of certificate chain validation.key_usage
: Bitmask of key usage flags to check for validity.key_usage_critical
: Boolean value indicating whether the Key Usage extension is considered critical.extension_critical
: Boolean value indicating whether extension constraints are considered critical.
Examples
Example 1: Limit Certificate Chain Depth
int ret = gnutls_certificate_set_verify_limits(cert, 5, 0, 0, 0);
if (ret < 0) {
// Error handling
}
Example 2: Enforce Key Usage
int ret = gnutls_certificate_set_verify_limits(cert, 0, GNUTLS_KU_DIGITAL_SIGNATURE | GNUTLS_KU_KEY_ENCIPHERMENT, 1, 0);
if (ret < 0) {
// Error handling
}
Common Issues
- Invalid depth limit: Users may encounter errors if the depth limit is set too low, resulting in an incomplete certificate chain validation.
- Missing Key Usage: If a certificate lacks the necessary key usage flags, verification may fail when
key_usage_critical
is set to true.
Integration
gnutls_certificate_set_verify_limits
can be used in conjunction with other GnuTLS functions for comprehensive certificate validation.
gnutls_certificate_verify_peers2(session, hostname);
Related Commands
gnutls_certificate_verify_peers2
: Verifies the peer certificates against a trust store.gnutls_certificate_get_verify_status
: Retrieves the verification status of a certificate.