/*
 * X.509v3 certificate parsing and processing
 * Copyright (c) 2006-2011, Jouni Malinen <j@w1.fi>
 *
 * This software may be distributed under the terms of the BSD license.
 * See README for more details.
 */

#ifndef X509V3_H
#define X509V3_H

#include "asn1.h"

struct x509_algorithm_identifier {
	struct asn1_oid oid;
};

struct x509_name_attr {
	enum x509_name_attr_type {
		X509_NAME_ATTR_NOT_USED,
		X509_NAME_ATTR_DC,
		X509_NAME_ATTR_CN,
		X509_NAME_ATTR_C,
		X509_NAME_ATTR_L,
		X509_NAME_ATTR_ST,
		X509_NAME_ATTR_O,
		X509_NAME_ATTR_OU
	} type;
	char *value;
};

#define X509_MAX_NAME_ATTRIBUTES 20

struct x509_name {
	struct x509_name_attr attr[X509_MAX_NAME_ATTRIBUTES];
	size_t num_attr;
	char *email; /* emailAddress */

	/* from alternative name extension */
	char *alt_email; /* rfc822Name */
	char *dns; /* dNSName */
	char *uri; /* uniformResourceIdentifier */
	u8 *ip; /* iPAddress */
	size_t ip_len; /* IPv4: 4, IPv6: 16 */
	struct asn1_oid rid; /* registeredID */
};

#define X509_MAX_SERIAL_NUM_LEN 20

struct x509_certificate {
	struct x509_certificate *next;
	enum { X509_CERT_V1 = 0, X509_CERT_V2 = 1, X509_CERT_V3 = 2 } version;
	u8 serial_number[X509_MAX_SERIAL_NUM_LEN];
	size_t serial_number_len;
	struct x509_algorithm_identifier signature;
	struct x509_name issuer;
	struct x509_name subject;
	u8 *subject_dn;
	size_t subject_dn_len;
	os_time_t not_before;
	os_time_t not_after;
	struct x509_algorithm_identifier public_key_alg;
	u8 *public_key;
	size_t public_key_len;
	struct x509_algorithm_identifier signature_alg;
	u8 *sign_value;
	size_t sign_value_len;

	/* Extensions */
	unsigned int extensions_present;
#define X509_EXT_BASIC_CONSTRAINTS		(1 << 0)
#define X509_EXT_PATH_LEN_CONSTRAINT		(1 << 1)
#define X509_EXT_KEY_USAGE			(1 << 2)
#define X509_EXT_SUBJECT_ALT_NAME		(1 << 3)
#define X509_EXT_ISSUER_ALT_NAME		(1 << 4)
#define X509_EXT_EXT_KEY_USAGE			(1 << 5)

	/* BasicConstraints */
	int ca; /* cA */
	unsigned long path_len_constraint; /* pathLenConstraint */

	/* KeyUsage */
	unsigned long key_usage;
#define X509_KEY_USAGE_DIGITAL_SIGNATURE	(1 << 0)
#define X509_KEY_USAGE_NON_REPUDIATION		(1 << 1)
#define X509_KEY_USAGE_KEY_ENCIPHERMENT		(1 << 2)
#define X509_KEY_USAGE_DATA_ENCIPHERMENT	(1 << 3)
#define X509_KEY_USAGE_KEY_AGREEMENT		(1 << 4)
#define X509_KEY_USAGE_KEY_CERT_SIGN		(1 << 5)
#define X509_KEY_USAGE_CRL_SIGN			(1 << 6)
#define X509_KEY_USAGE_ENCIPHER_ONLY		(1 << 7)
#define X509_KEY_USAGE_DECIPHER_ONLY		(1 << 8)

	/* ExtKeyUsage */
	unsigned long ext_key_usage;
#define X509_EXT_KEY_USAGE_ANY			(1 << 0)
#define X509_EXT_KEY_USAGE_SERVER_AUTH		(1 << 1)
#define X509_EXT_KEY_USAGE_CLIENT_AUTH		(1 << 2)
#define X509_EXT_KEY_USAGE_OCSP			(1 << 3)

	/*
	 * The DER format certificate follows struct x509_certificate. These
	 * pointers point to that buffer.
	 */
	const u8 *cert_start;
	size_t cert_len;
	const u8 *tbs_cert_start;
	size_t tbs_cert_len;

	/* Meta data used for certificate validation */
	unsigned int ocsp_good:1;
	unsigned int ocsp_revoked:1;
	unsigned int issuer_trusted:1;
};

enum {
	X509_VALIDATE_OK,
	X509_VALIDATE_BAD_CERTIFICATE,
	X509_VALIDATE_UNSUPPORTED_CERTIFICATE,
	X509_VALIDATE_CERTIFICATE_REVOKED,
	X509_VALIDATE_CERTIFICATE_EXPIRED,
	X509_VALIDATE_CERTIFICATE_UNKNOWN,
	X509_VALIDATE_UNKNOWN_CA
};

void x509_certificate_free(struct x509_certificate *cert);
int x509_parse_algorithm_identifier(const u8 *buf, size_t len,
				    struct x509_algorithm_identifier *id,
				    const u8 **next);
int x509_parse_name(const u8 *buf, size_t len, struct x509_name *name,
		    const u8 **next);
int x509_parse_time(const u8 *buf, size_t len, u8 asn1_tag, os_time_t *val);
struct x509_certificate * x509_certificate_parse(const u8 *buf, size_t len);
void x509_free_name(struct x509_name *name);
void x509_name_string(struct x509_name *name, char *buf, size_t len);
int x509_name_compare(struct x509_name *a, struct x509_name *b);
void x509_certificate_chain_free(struct x509_certificate *cert);
int x509_check_signature(struct x509_certificate *issuer,
			 struct x509_algorithm_identifier *signature,
			 const u8 *sign_value, size_t sign_value_len,
			 const u8 *signed_data, size_t signed_data_len);
int x509_certificate_check_signature(struct x509_certificate *issuer,
				     struct x509_certificate *cert);
int x509_certificate_chain_validate(struct x509_certificate *trusted,
				    struct x509_certificate *chain,
				    int *reason, int disable_time_checks);
struct x509_certificate *
x509_certificate_get_subject(struct x509_certificate *chain,
			     struct x509_name *name);
int x509_certificate_self_signed(struct x509_certificate *cert);

int x509_sha1_oid(struct asn1_oid *oid);
int x509_sha256_oid(struct asn1_oid *oid);
int x509_sha384_oid(struct asn1_oid *oid);
int x509_sha512_oid(struct asn1_oid *oid);

#endif /* X509V3_H */