include/mbedtls/x509.h

/**
 * \file x509.h
 *
 * \brief X.509 generic defines and structures
 */
/*
 *  Copyright The Mbed TLS Contributors
 *  SPDX-License-Identifier: Apache-2.0 OR GPL-2.0-or-later
 *
 *  This file is provided under the Apache License 2.0, or the
 *  GNU General Public License v2.0 or later.
 *
 *  **********
 *  Apache License 2.0:
 *
 *  Licensed under the Apache License, Version 2.0 (the "License"); you may
 *  not use this file except in compliance with the License.
 *  You may obtain a copy of the License at
 *
 *  http://www.apache.org/licenses/LICENSE-2.0
 *
 *  Unless required by applicable law or agreed to in writing, software
 *  distributed under the License is distributed on an "AS IS" BASIS, WITHOUT
 *  WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 *  See the License for the specific language governing permissions and
 *  limitations under the License.
 *
 *  **********
 *
 *  **********
 *  GNU General Public License v2.0 or later:
 *
 *  This program is free software; you can redistribute it and/or modify
 *  it under the terms of the GNU General Public License as published by
 *  the Free Software Foundation; either version 2 of the License, or
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 *
 *  This program is distributed in the hope that it will be useful,
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 *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
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 *  with this program; if not, write to the Free Software Foundation, Inc.,
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#ifndef MBEDTLS_X509_H
#define MBEDTLS_X509_H

#if !defined(MBEDTLS_CONFIG_FILE)
#include "config.h"
#else
#include MBEDTLS_CONFIG_FILE
#endif

#include "asn1.h"
#include "pk.h"

#if defined(MBEDTLS_RSA_C)
#include "rsa.h"
#endif

/**
 * \addtogroup x509_module
 * \{
 */

#if !defined(MBEDTLS_X509_MAX_INTERMEDIATE_CA)
/**
 * Maximum number of intermediate CAs in a verification chain.
 * That is, maximum length of the chain, excluding the end-entity certificate
 * and the trusted root certificate.
 *
 * Set this to a low value to prevent an adversary from making you waste
 * resources verifying an overlong certificate chain.
 */
#define MBEDTLS_X509_MAX_INTERMEDIATE_CA   8
#endif

/**
 * \name X509 Error codes
 * \{
 */
/** Unavailable feature, e.g. RSA hashing/encryption combination. */
#define MBEDTLS_ERR_X509_FEATURE_UNAVAILABLE              -0x2080
/** Requested OID is unknown. */
#define MBEDTLS_ERR_X509_UNKNOWN_OID                      -0x2100
/** The CRT/CRL/CSR format is invalid, e.g. different type expected. */
#define MBEDTLS_ERR_X509_INVALID_FORMAT                   -0x2180
/** The CRT/CRL/CSR version element is invalid. */
#define MBEDTLS_ERR_X509_INVALID_VERSION                  -0x2200
/** The serial tag or value is invalid. */
#define MBEDTLS_ERR_X509_INVALID_SERIAL                   -0x2280
/** The algorithm tag or value is invalid. */
#define MBEDTLS_ERR_X509_INVALID_ALG                      -0x2300
/** The name tag or value is invalid. */
#define MBEDTLS_ERR_X509_INVALID_NAME                     -0x2380
/** The date tag or value is invalid. */
#define MBEDTLS_ERR_X509_INVALID_DATE                     -0x2400
/** The signature tag or value invalid. */
#define MBEDTLS_ERR_X509_INVALID_SIGNATURE                -0x2480
/** The extension tag or value is invalid. */
#define MBEDTLS_ERR_X509_INVALID_EXTENSIONS               -0x2500
/** CRT/CRL/CSR has an unsupported version number. */
#define MBEDTLS_ERR_X509_UNKNOWN_VERSION                  -0x2580
/** Signature algorithm (oid) is unsupported. */
#define MBEDTLS_ERR_X509_UNKNOWN_SIG_ALG                  -0x2600
/** Signature algorithms do not match. (see \c ::mbedtls_x509_crt sig_oid) */
#define MBEDTLS_ERR_X509_SIG_MISMATCH                     -0x2680
/** Certificate verification failed, e.g. CRL, CA or signature check failed. */
#define MBEDTLS_ERR_X509_CERT_VERIFY_FAILED               -0x2700
/** Format not recognized as DER or PEM. */
#define MBEDTLS_ERR_X509_CERT_UNKNOWN_FORMAT              -0x2780
/** Input invalid. */
#define MBEDTLS_ERR_X509_BAD_INPUT_DATA                   -0x2800
/** Allocation of memory failed. */
#define MBEDTLS_ERR_X509_ALLOC_FAILED                     -0x2880
/** Read/write of file failed. */
#define MBEDTLS_ERR_X509_FILE_IO_ERROR                    -0x2900
/** Destination buffer is too small. */
#define MBEDTLS_ERR_X509_BUFFER_TOO_SMALL                 -0x2980
/** A fatal error occurred, eg the chain is too long or the vrfy callback failed. */
#define MBEDTLS_ERR_X509_FATAL_ERROR                      -0x3000
/* \} name */

/**
 * \name X509 Verify codes
 * \{
 */
/* Reminder: update x509_crt_verify_strings[] in library/x509_crt.c */
#define MBEDTLS_X509_BADCERT_EXPIRED             0x01  /**< The certificate validity has expired. */
#define MBEDTLS_X509_BADCERT_REVOKED             0x02  /**< The certificate has been revoked (is on a CRL). */
#define MBEDTLS_X509_BADCERT_CN_MISMATCH         0x04  /**< The certificate Common Name (CN) does not match with the expected CN. */
#define MBEDTLS_X509_BADCERT_NOT_TRUSTED         0x08  /**< The certificate is not correctly signed by the trusted CA. */
#define MBEDTLS_X509_BADCRL_NOT_TRUSTED          0x10  /**< The CRL is not correctly signed by the trusted CA. */
#define MBEDTLS_X509_BADCRL_EXPIRED              0x20  /**< The CRL is expired. */
#define MBEDTLS_X509_BADCERT_MISSING             0x40  /**< Certificate was missing. */
#define MBEDTLS_X509_BADCERT_SKIP_VERIFY         0x80  /**< Certificate verification was skipped. */
#define MBEDTLS_X509_BADCERT_OTHER             0x0100  /**< Other reason (can be used by verify callback) */
#define MBEDTLS_X509_BADCERT_FUTURE            0x0200  /**< The certificate validity starts in the future. */
#define MBEDTLS_X509_BADCRL_FUTURE             0x0400  /**< The CRL is from the future */
#define MBEDTLS_X509_BADCERT_KEY_USAGE         0x0800  /**< Usage does not match the keyUsage extension. */
#define MBEDTLS_X509_BADCERT_EXT_KEY_USAGE     0x1000  /**< Usage does not match the extendedKeyUsage extension. */
#define MBEDTLS_X509_BADCERT_NS_CERT_TYPE      0x2000  /**< Usage does not match the nsCertType extension. */
#define MBEDTLS_X509_BADCERT_BAD_MD            0x4000  /**< The certificate is signed with an unacceptable hash. */
#define MBEDTLS_X509_BADCERT_BAD_PK            0x8000  /**< The certificate is signed with an unacceptable PK alg (eg RSA vs ECDSA). */
#define MBEDTLS_X509_BADCERT_BAD_KEY         0x010000  /**< The certificate is signed with an unacceptable key (eg bad curve, RSA too short). */
#define MBEDTLS_X509_BADCRL_BAD_MD           0x020000  /**< The CRL is signed with an unacceptable hash. */
#define MBEDTLS_X509_BADCRL_BAD_PK           0x040000  /**< The CRL is signed with an unacceptable PK alg (eg RSA vs ECDSA). */
#define MBEDTLS_X509_BADCRL_BAD_KEY          0x080000  /**< The CRL is signed with an unacceptable key (eg bad curve, RSA too short). */

/* \} name */
/* \} addtogroup x509_module */

/*
 * X.509 v3 Key Usage Extension flags
 * Reminder: update x509_info_key_usage() when adding new flags.
 */
#define MBEDTLS_X509_KU_DIGITAL_SIGNATURE            (0x80)  /* bit 0 */
#define MBEDTLS_X509_KU_NON_REPUDIATION              (0x40)  /* bit 1 */
#define MBEDTLS_X509_KU_KEY_ENCIPHERMENT             (0x20)  /* bit 2 */
#define MBEDTLS_X509_KU_DATA_ENCIPHERMENT            (0x10)  /* bit 3 */
#define MBEDTLS_X509_KU_KEY_AGREEMENT                (0x08)  /* bit 4 */
#define MBEDTLS_X509_KU_KEY_CERT_SIGN                (0x04)  /* bit 5 */
#define MBEDTLS_X509_KU_CRL_SIGN                     (0x02)  /* bit 6 */
#define MBEDTLS_X509_KU_ENCIPHER_ONLY                (0x01)  /* bit 7 */
#define MBEDTLS_X509_KU_DECIPHER_ONLY              (0x8000)  /* bit 8 */

/*
 * Netscape certificate types
 * (http://www.mozilla.org/projects/security/pki/nss/tech-notes/tn3.html)
 */

#define MBEDTLS_X509_NS_CERT_TYPE_SSL_CLIENT         (0x80)  /* bit 0 */
#define MBEDTLS_X509_NS_CERT_TYPE_SSL_SERVER         (0x40)  /* bit 1 */
#define MBEDTLS_X509_NS_CERT_TYPE_EMAIL              (0x20)  /* bit 2 */
#define MBEDTLS_X509_NS_CERT_TYPE_OBJECT_SIGNING     (0x10)  /* bit 3 */
#define MBEDTLS_X509_NS_CERT_TYPE_RESERVED           (0x08)  /* bit 4 */
#define MBEDTLS_X509_NS_CERT_TYPE_SSL_CA             (0x04)  /* bit 5 */
#define MBEDTLS_X509_NS_CERT_TYPE_EMAIL_CA           (0x02)  /* bit 6 */
#define MBEDTLS_X509_NS_CERT_TYPE_OBJECT_SIGNING_CA  (0x01)  /* bit 7 */

/*
 * X.509 extension types
 *
 * Comments refer to the status for using certificates. Status can be
 * different for writing certificates or reading CRLs or CSRs.
 */
#define MBEDTLS_X509_EXT_AUTHORITY_KEY_IDENTIFIER    (1 << 0)
#define MBEDTLS_X509_EXT_SUBJECT_KEY_IDENTIFIER      (1 << 1)
#define MBEDTLS_X509_EXT_KEY_USAGE                   (1 << 2)
#define MBEDTLS_X509_EXT_CERTIFICATE_POLICIES        (1 << 3)
#define MBEDTLS_X509_EXT_POLICY_MAPPINGS             (1 << 4)
#define MBEDTLS_X509_EXT_SUBJECT_ALT_NAME            (1 << 5)    /* Supported (DNS) */
#define MBEDTLS_X509_EXT_ISSUER_ALT_NAME             (1 << 6)
#define MBEDTLS_X509_EXT_SUBJECT_DIRECTORY_ATTRS     (1 << 7)
#define MBEDTLS_X509_EXT_BASIC_CONSTRAINTS           (1 << 8)    /* Supported */
#define MBEDTLS_X509_EXT_NAME_CONSTRAINTS            (1 << 9)
#define MBEDTLS_X509_EXT_POLICY_CONSTRAINTS          (1 << 10)
#define MBEDTLS_X509_EXT_EXTENDED_KEY_USAGE          (1 << 11)
#define MBEDTLS_X509_EXT_CRL_DISTRIBUTION_POINTS     (1 << 12)
#define MBEDTLS_X509_EXT_INIHIBIT_ANYPOLICY          (1 << 13)
#define MBEDTLS_X509_EXT_FRESHEST_CRL                (1 << 14)

#define MBEDTLS_X509_EXT_NS_CERT_TYPE                (1 << 16)

/*
 * Storage format identifiers
 * Recognized formats: PEM and DER
 */
#define MBEDTLS_X509_FORMAT_DER                 1
#define MBEDTLS_X509_FORMAT_PEM                 2

#define MBEDTLS_X509_MAX_DN_NAME_SIZE         256 /**< Maximum value size of a DN entry */

#ifdef __cplusplus
extern "C" {
#endif

/**
 * \addtogroup x509_module
 * \{ */

/**
 * \name Structures for parsing X.509 certificates, CRLs and CSRs
 * \{
 */

/**
 * Type-length-value structure that allows for ASN1 using DER.
 */
typedef mbedtls_asn1_buf mbedtls_x509_buf;

/**
 * Container for ASN1 bit strings.
 */
typedef mbedtls_asn1_bitstring mbedtls_x509_bitstring;

/**
 * Container for ASN1 named information objects.
 * It allows for Relative Distinguished Names (e.g. cn=localhost,ou=code,etc.).
 */
typedef mbedtls_asn1_named_data mbedtls_x509_name;

/**
 * Container for a sequence of ASN.1 items
 */
typedef mbedtls_asn1_sequence mbedtls_x509_sequence;

/** Container for date and time (precision in seconds). */
typedef struct mbedtls_x509_time
{
    int year, mon, day;         /**< Date. */
    int hour, min, sec;         /**< Time. */
}
mbedtls_x509_time;

/** \} name Structures for parsing X.509 certificates, CRLs and CSRs */
/** \} addtogroup x509_module */

/**
 * \brief          Store the certificate DN in printable form into buf;
 *                 no more than size characters will be written.
 *
 * \param buf      Buffer to write to
 * \param size     Maximum size of buffer
 * \param dn       The X509 name to represent
 *
 * \return         The length of the string written (not including the
 *                 terminated nul byte), or a negative error code.
 */
int mbedtls_x509_dn_gets( char *buf, size_t size, const mbedtls_x509_name *dn );

/**
 * \brief          Store the certificate serial in printable form into buf;
 *                 no more than size characters will be written.
 *
 * \param buf      Buffer to write to
 * \param size     Maximum size of buffer
 * \param serial   The X509 serial to represent
 *
 * \return         The length of the string written (not including the
 *                 terminated nul byte), or a negative error code.
 */
int mbedtls_x509_serial_gets( char *buf, size_t size, const mbedtls_x509_buf *serial );

/**
 * \brief          Check a given mbedtls_x509_time against the system time
 *                 and tell if it's in the past.
 *
 * \note           Intended usage is "if( is_past( valid_to ) ) ERROR".
 *                 Hence the return value of 1 if on internal errors.
 *
 * \param to       mbedtls_x509_time to check
 *
 * \return         1 if the given time is in the past or an error occurred,
 *                 0 otherwise.
 */
int mbedtls_x509_time_is_past( const mbedtls_x509_time *to );

/**
 * \brief          Check a given mbedtls_x509_time against the system time
 *                 and tell if it's in the future.
 *
 * \note           Intended usage is "if( is_future( valid_from ) ) ERROR".
 *                 Hence the return value of 1 if on internal errors.
 *
 * \param from     mbedtls_x509_time to check
 *
 * \return         1 if the given time is in the future or an error occurred,
 *                 0 otherwise.
 */
int mbedtls_x509_time_is_future( const mbedtls_x509_time *from );

#if defined(MBEDTLS_SELF_TEST)

/**
 * \brief          Checkup routine
 *
 * \return         0 if successful, or 1 if the test failed
 */
int mbedtls_x509_self_test( int verbose );

#endif /* MBEDTLS_SELF_TEST */

/*
 * Internal module functions. You probably do not want to use these unless you
 * know you do.
 */
int mbedtls_x509_get_name( unsigned char **p, const unsigned char *end,
                   mbedtls_x509_name *cur );
int mbedtls_x509_get_alg_null( unsigned char **p, const unsigned char *end,
                       mbedtls_x509_buf *alg );
int mbedtls_x509_get_alg( unsigned char **p, const unsigned char *end,
                  mbedtls_x509_buf *alg, mbedtls_x509_buf *params );
#if defined(MBEDTLS_X509_RSASSA_PSS_SUPPORT)
int mbedtls_x509_get_rsassa_pss_params( const mbedtls_x509_buf *params,
                                mbedtls_md_type_t *md_alg, mbedtls_md_type_t *mgf_md,
                                int *salt_len );
#endif
int mbedtls_x509_get_sig( unsigned char **p, const unsigned char *end, mbedtls_x509_buf *sig );
int mbedtls_x509_get_sig_alg( const mbedtls_x509_buf *sig_oid, const mbedtls_x509_buf *sig_params,
                      mbedtls_md_type_t *md_alg, mbedtls_pk_type_t *pk_alg,
                      void **sig_opts );
int mbedtls_x509_get_time( unsigned char **p, const unsigned char *end,
                   mbedtls_x509_time *t );
int mbedtls_x509_get_serial( unsigned char **p, const unsigned char *end,
                     mbedtls_x509_buf *serial );
int mbedtls_x509_get_ext( unsigned char **p, const unsigned char *end,
                  mbedtls_x509_buf *ext, int tag );
int mbedtls_x509_sig_alg_gets( char *buf, size_t size, const mbedtls_x509_buf *sig_oid,
                       mbedtls_pk_type_t pk_alg, mbedtls_md_type_t md_alg,
                       const void *sig_opts );
int mbedtls_x509_key_size_helper( char *buf, size_t buf_size, const char *name );
int mbedtls_x509_string_to_names( mbedtls_asn1_named_data **head, const char *name );
int mbedtls_x509_set_extension( mbedtls_asn1_named_data **head, const char *oid, size_t oid_len,
                        int critical, const unsigned char *val,
                        size_t val_len );
int mbedtls_x509_write_extensions( unsigned char **p, unsigned char *start,
                           mbedtls_asn1_named_data *first );
int mbedtls_x509_write_names( unsigned char **p, unsigned char *start,
                      mbedtls_asn1_named_data *first );
int mbedtls_x509_write_sig( unsigned char **p, unsigned char *start,
                    const char *oid, size_t oid_len,
                    unsigned char *sig, size_t size );

#define MBEDTLS_X509_SAFE_SNPRINTF                          \
    do {                                                    \
        if( ret < 0 || (size_t) ret >= n )                  \
            return( MBEDTLS_ERR_X509_BUFFER_TOO_SMALL );    \
                                                            \
        n -= (size_t) ret;                                  \
        p += (size_t) ret;                                  \
    } while( 0 )

#ifdef __cplusplus
}
#endif

#endif /* x509.h */