Extracts DER-encoded data from a PEM-formatted string. Supports multiple possible PEM header names for flexibility.
The PEM-formatted string
The PEM header name(s) to look for (e.g., "CERTIFICATE")
The DER-encoded bytes
Error if multiple PEM blocks are found or format is invalid
Extracts DER-encoded data from a PEM-formatted string. Supports multiple possible PEM header names for flexibility.