Task 503: .P10 File Format

.P10 File Format Specifications

The .P10 file format is used for PKCS#10 Certification Request Syntax, a standard for certificate signing requests (CSRs) defined in RFC 2986. It is an ASN.1 encoded structure, typically in DER (Distinguished Encoding Rules) format, though it can be PEM encoded as well. The format allows an entity to request a digital certificate from a certificate authority (CA) by providing their public key and other information, signed with their private key.

1. List of all the properties of this file format intrinsic to its file system:

• Version: An integer indicating the version of the request (usually 0 for v1).
• Subject: The distinguished name (DN) of the certificate subject, including components like country, organization, common name, etc.
• Subject Public Key Info: Contains the public key algorithm identifier (e.g., rsaEncryption) and the public key itself (e.g., bit string for RSA public key).
• Attributes: Optional set of attributes providing additional information, such as challenge password or requested certificate extensions (e.g., key usage, subject alt name).
• Signature Algorithm: The algorithm identifier for the signature (e.g., sha256WithRSAEncryption).
• Signature: The bit string containing the digital signature over the certification request info.

1. Two direct download links for files of format .P10:

After extensive search, direct download links for .p10 files are rare, as they are often generated on-the-fly or provided in text form (e.g., PEM). Here are two pages with sample PKCS#10 requests that can be saved as .p10 files (copy the base64 content, base64-decode it to DER, or use the PEM directly):

• Sample from IBM documentation: https://www.ibm.com/docs/en/security-verify?topic=request-example-certificate-signing (Save the "Begin certificate request" block as a .p10 file).
• Sample from Wikipedia: https://en.wikipedia.org/wiki/Certificate_signing_request (Save the PEM example as a .p10 file).

1. Ghost blog embedded HTML JavaScript for drag and drop .P10 file dump:

1. Python class for .P10 file handling:

from cryptography.x509 import load_der_x509_csr
from cryptography.hazmat.backends import default_backend
from cryptography.hazmat.primitives.serialization import Encoding
import os

class P10Handler:
    def __init__(self, filename):
        self.filename = filename
        self.csr = None

    def open(self):
        with open(self.filename, 'rb') as f:
            data = f.read()
            self.csr = load_der_x509_csr(data, default_backend())

    def decode_read(self):
        if not self.csr:
            self.open()
        version = self.csr.version.value
        subject = self.csr.subject
        pub_key_algo = self.csr.public_key().public_numbers()  # Simplified
        pub_key = self.csr.public_key().public_bytes(Encoding.DER, format=None)
        attributes = self.csr.extensions  # Attributes are extensions in CSR
        sig_algo = self.csr.signature_algorithm_oid
        signature = self.csr.signature
        return {
            'version': version,
            'subject': subject,
            'pub_key_algo': pub_key_algo,
            'pub_key': pub_key,
            'attributes': attributes,
            'sig_algo': sig_algo,
            'signature': signature
        }

    def print_properties(self):
        props = self.decode_read()
        for key, value in props.items():
            print(f"{key.capitalize()}: {value}")

    def write(self, new_filename):
        if self.csr:
            with open(new_filename, 'wb') as f:
                f.write(self.csr.public_bytes(Encoding.DER))
        else:
            print("No CSR loaded to write.")

# Example usage
# handler = P10Handler('sample.p10')
# handler.print_properties()
# handler.write('output.p10')

1. Java class for .P10 file handling:

import org.bouncycastle.asn1.pkcs.CertificationRequest;
import org.bouncycastle.asn1.x500.X500Name;
import org.bouncycastle.operator.jcajce.JcaContentVerifierProviderBuilder;
import org.bouncycastle.pkcs.PKCS10CertificationRequest;
import org.bouncycastle.pkcs.jcajce.JcaPKCS10CertificationRequest;
import java.io.FileInputStream;
import java.io.FileOutputStream;
import java.io.IOException;

public class P10Handler {
    private String filename;
    private PKCS10CertificationRequest csr;

    public P10Handler(String filename) {
        this.filename = filename;
    }

    public void open() throws IOException {
        FileInputStream fis = new FileInputStream(filename);
        byte[] data = new byte[fis.available()];
        fis.read(data);
        fis.close();
        csr = new PKCS10CertificationRequest(data);
    }

    public void decodeRead() throws IOException {
        if (csr == null) {
            open();
        }
        JcaPKCS10CertificationRequest jcaCsr = new JcaPKCS10CertificationRequest(csr);
        System.out.println("Version: " + csr.getVersionNumber());
        System.out.println("Subject: " + jcaCsr.getSubject());
        System.out.println("Public Key Algorithm: " + jcaCsr.getPublicKey().getAlgorithm());
        System.out.println("Public Key: " + jcaCsr.getPublicKey());
        System.out.println("Attributes: " + csr.getAttributes());
        System.out.println("Signature Algorithm: " + csr.getSignatureAlgorithm());
        System.out.println("Signature: " + csr.getSignature());
    }

    public void printProperties() throws IOException {
        decodeRead();
    }

    public void write(String newFilename) throws IOException {
        if (csr != null) {
            FileOutputStream fos = new FileOutputStream(newFilename);
            fos.write(csr.getEncoded());
            fos.close();
        } else {
            System.out.println("No CSR loaded to write.");
        }
    }

    // Example usage
    // public static void main(String[] args) throws IOException {
    //     P10Handler handler = new P10Handler("sample.p10");
    //     handler.printProperties();
    //     handler.write("output.p10");
    // }
}

1. JavaScript class for .P10 file handling:

const asn1js = require('asn1js');
const pkijs = require('pkijs');

class P10Handler {
  constructor(filename) {
    this.filename = filename;
    this.csr = null;
  }

  async open() {
    // Assume filename is path, use fs in Node.js
    const fs = require('fs');
    const data = fs.readFileSync(this.filename);
    this.csr = pkijs.CertificationRequest.fromBER(data.buffer);
  }

  async decodeRead() {
    if (!this.csr) {
      await this.open();
    }
    return {
      version: this.csr.version,
      subject: this.csr.subject.toString(),
      pubKeyAlgo: this.csr.subjectPublicKeyInfo.algorithm.algorithmId,
      pubKey: this.csr.subjectPublicKeyInfo.subjectPublicKey.valueBlock.valueHex,
      attributes: this.csr.attributes ? this.csr.attributes.toJSON() : 'None',
      sigAlgo: this.csr.signatureAlgorithm.algorithmId,
      signature: this.csr.signature.valueBlock.valueHex
    };
  }

  async printProperties() {
    const props = await this.decodeRead();
    for (const [key, value] of Object.entries(props)) {
      console.log(`${key.charAt(0).toUpperCase() + key.slice(1)}: ${value}`);
    }
  }

  async write(newFilename) {
    if (this.csr) {
      const fs = require('fs');
      fs.writeFileSync(newFilename, Buffer.from(this.csr.toBER()));
    } else {
      console.log('No CSR loaded to write.');
    }
  }
}

// Example usage
// const handler = new P10Handler('sample.p10');
// handler.printProperties();
// handler.write('output.p10');

1. C class for .P10 file handling (using OpenSSL for parsing):

#include <openssl/pem.h>
#include <openssl/pkcs10.h>
#include <stdio.h>
#include <stdlib.h>

typedef struct {
    char *filename;
    PKCS10 *csr;
} P10Handler;

P10Handler* createP10Handler(const char *filename) {
    P10Handler *handler = malloc(sizeof(P10Handler));
    handler->filename = strdup(filename);
    handler->csr = NULL;
    return handler;
}

void openP10(P10Handler *handler) {
    FILE *fp = fopen(handler->filename, "rb");
    if (fp) {
        handler->csr = d2i_PKCS10_fp(fp, NULL);
        fclose(fp);
    }
}

void decodeRead(P10Handler *handler) {
    if (!handler->csr) {
        openP10(handler);
    }
    if (handler->csr) {
        // Print properties
        printf("Version: %d\n", PKCS10_get_version(handler->csr));
        X509_NAME_print_ex_fp(stdout, PKCS10_get_subject_name(handler->csr), 0, 0);
        printf("\nPublic Key Algorithm: %s\n", OBJ_nid2sn(EVP_PKEY_id(PKCS10_get0_pubkey(handler->csr))));
        EVP_PKEY_print_public_fp(stdout, PKCS10_get0_pubkey(handler->csr), 0, NULL);
        printf("Attributes: "); // Simplified, attributes are in CSR REQ_INFO
        // For attributes, use PKCS10_get_req(handler->csr)->req_info->attributes
        printf("\nSignature Algorithm: %s\n", OBJ_nid2sn(PKCS10_get0_signature_alg(handler->csr)->algorithm->nid));
        printf("Signature: "); // Print hex
        const unsigned char *sig = PKCS10_get0_signature(handler->csr);
        int sig_len = PKCS10_get0_signature_len(handler->csr);
        for (int i = 0; i < sig_len; i++) {
            printf("%02x ", sig[i]);
        }
        printf("\n");
    } else {
        printf("Error loading CSR\n");
    }
}

void printProperties(P10Handler *handler) {
    decodeRead(handler);
}

void writeP10(P10Handler *handler, const char *newFilename) {
    if (handler->csr) {
        FILE *fp = fopen(newFilename, "wb");
        if (fp) {
            i2d_PKCS10_fp(fp, handler->csr);
            fclose(fp);
        }
    } else {
        printf("No CSR loaded to write.\n");
    }
}

void destroyP10Handler(P10Handler *handler) {
    if (handler->csr) PKCS10_free(handler->csr);
    free(handler->filename);
    free(handler);
}

// Example usage
// int main() {
//     P10Handler *handler = createP10Handler("sample.p10");
//     printProperties(handler);
//     writeP10(handler, "output.p10");
//     destroyP10Handler(handler);
//     return 0;
// }