/** * \file x509_crt.h * * \brief X.509 certificate parsing and writing * * Copyright (C) 2006-2013, Brainspark B.V. * * This file is part of PolarSSL (http://www.polarssl.org) * Lead Maintainer: Paul Bakker * * All rights reserved. * * 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 * (at your option) any later version. * * This program is distributed in the hope that it will be useful, * but WITHOUT ANY WARRANTY; without even the implied warranty of * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the * GNU General Public License for more details. * * You should have received a copy of the GNU General Public License along * with this program; if not, write to the Free Software Foundation, Inc., * 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA. */ #ifndef POLARSSL_X509_CRT_H #define POLARSSL_X509_CRT_H #include "config.h" #include "x509.h" #include "x509_crl.h" /** * \addtogroup x509_module * \{ */ #ifdef __cplusplus extern "C" { #endif /** * \name Structures and functions for parsing and writing X.509 certificates * \{ */ /** * Container for an X.509 certificate. The certificate may be chained. */ typedef struct _x509_crt { x509_buf raw; /**< The raw certificate data (DER). */ x509_buf tbs; /**< The raw certificate body (DER). The part that is To Be Signed. */ int version; /**< The X.509 version. (0=v1, 1=v2, 2=v3) */ x509_buf serial; /**< Unique id for certificate issued by a specific CA. */ x509_buf sig_oid1; /**< Signature algorithm, e.g. sha1RSA */ x509_buf issuer_raw; /**< The raw issuer data (DER). Used for quick comparison. */ x509_buf subject_raw; /**< The raw subject data (DER). Used for quick comparison. */ x509_name issuer; /**< The parsed issuer data (named information object). */ x509_name subject; /**< The parsed subject data (named information object). */ x509_time valid_from; /**< Start time of certificate validity. */ x509_time valid_to; /**< End time of certificate validity. */ pk_context pk; /**< Container for the public key context. */ x509_buf issuer_id; /**< Optional X.509 v2/v3 issuer unique identifier. */ x509_buf subject_id; /**< Optional X.509 v2/v3 subject unique identifier. */ x509_buf v3_ext; /**< Optional X.509 v3 extensions. */ x509_sequence subject_alt_names; /**< Optional list of Subject Alternative Names (Only dNSName supported). */ int ext_types; /**< Bit string containing detected and parsed extensions */ int ca_istrue; /**< Optional Basic Constraint extension value: 1 if this certificate belongs to a CA, 0 otherwise. */ int max_pathlen; /**< Optional Basic Constraint extension value: The maximum path length to the root certificate. Path length is 1 higher than RFC 5280 'meaning', so 1+ */ unsigned char key_usage; /**< Optional key usage extension value: See the values in x509.h */ x509_sequence ext_key_usage; /**< Optional list of extended key usage OIDs. */ unsigned char ns_cert_type; /**< Optional Netscape certificate type extension value: See the values in x509.h */ x509_buf sig_oid2; /**< Signature algorithm. Must match sig_oid1. */ x509_buf sig; /**< Signature: hash of the tbs part signed with the private key. */ md_type_t sig_md; /**< Internal representation of the MD algorithm of the signature algorithm, e.g. POLARSSL_MD_SHA256 */ pk_type_t sig_pk /**< Internal representation of the Public Key algorithm of the signature algorithm, e.g. POLARSSL_PK_RSA */; struct _x509_crt *next; /**< Next certificate in the CA-chain. */ } x509_crt; #define X509_CRT_VERSION_1 0 #define X509_CRT_VERSION_2 1 #define X509_CRT_VERSION_3 2 #define X509_RFC5280_MAX_SERIAL_LEN 32 #define X509_RFC5280_UTC_TIME_LEN 15 /** * Container for writing a certificate (CRT) */ typedef struct _x509write_cert { int version; mpi serial; pk_context *subject_key; pk_context *issuer_key; asn1_named_data *subject; asn1_named_data *issuer; md_type_t md_alg; char not_before[X509_RFC5280_UTC_TIME_LEN + 1]; char not_after[X509_RFC5280_UTC_TIME_LEN + 1]; asn1_named_data *extensions; } x509write_cert; #if defined(POLARSSL_X509_CRT_PARSE_C) /** * \brief Parse a single DER formatted certificate and add it * to the chained list. * * \param chain points to the start of the chain * \param buf buffer holding the certificate DER data * \param buflen size of the buffer * * \return 0 if successful, or a specific X509 or PEM error code */ int x509_crt_parse_der( x509_crt *chain, const unsigned char *buf, size_t buflen ); /** * \brief Parse one or more certificates and add them * to the chained list. Parses permissively. If some * certificates can be parsed, the result is the number * of failed certificates it encountered. If none complete * correctly, the first error is returned. * * \param chain points to the start of the chain * \param buf buffer holding the certificate data * \param buflen size of the buffer * * \return 0 if all certificates parsed successfully, a positive number * if partly successful or a specific X509 or PEM error code */ int x509_crt_parse( x509_crt *chain, const unsigned char *buf, size_t buflen ); #if defined(POLARSSL_FS_IO) /** * \brief Load one or more certificates and add them * to the chained list. Parses permissively. If some * certificates can be parsed, the result is the number * of failed certificates it encountered. If none complete * correctly, the first error is returned. * * \param chain points to the start of the chain * \param path filename to read the certificates from * * \return 0 if all certificates parsed successfully, a positive number * if partly successful or a specific X509 or PEM error code */ int x509_crt_parse_file( x509_crt *chain, const char *path ); /** * \brief Load one or more certificate files from a path and add them * to the chained list. Parses permissively. If some * certificates can be parsed, the result is the number * of failed certificates it encountered. If none complete * correctly, the first error is returned. * * \warning This function is NOT thread-safe unless * POLARSSL_THREADING_PTHREADS is defined. If you're using an * alternative threading implementation, you should either use * this function only in the main thread, or mutex it. * * \param chain points to the start of the chain * \param path directory / folder to read the certificate files from * * \return 0 if all certificates parsed successfully, a positive number * if partly successful or a specific X509 or PEM error code */ int x509_crt_parse_path( x509_crt *chain, const char *path ); #endif /* POLARSSL_FS_IO */ /** * \brief Returns an informational string about the * certificate. * * \param buf Buffer to write to * \param size Maximum size of buffer * \param prefix A line prefix * \param crt The X509 certificate to represent * * \return The amount of data written to the buffer, or -1 in * case of an error. */ int x509_crt_info( char *buf, size_t size, const char *prefix, const x509_crt *crt ); /** * \brief Verify the certificate signature * * The verify callback is a user-supplied callback that * can clear / modify / add flags for a certificate. If set, * the verification callback is called for each * certificate in the chain (from the trust-ca down to the * presented crt). The parameters for the callback are: * (void *parameter, x509_crt *crt, int certificate_depth, * int *flags). With the flags representing current flags for * that specific certificate and the certificate depth from * the bottom (Peer cert depth = 0). * * All flags left after returning from the callback * are also returned to the application. The function should * return 0 for anything but a fatal error. * * \param crt a certificate to be verified * \param trust_ca the trusted CA chain * \param ca_crl the CRL chain for trusted CA's * \param cn expected Common Name (can be set to * NULL if the CN must not be verified) * \param flags result of the verification * \param f_vrfy verification function * \param p_vrfy verification parameter * * \return 0 if successful or POLARSSL_ERR_X509_SIG_VERIFY_FAILED, * in which case *flags will have one or more of * the following values set: * BADCERT_EXPIRED -- * BADCERT_REVOKED -- * BADCERT_CN_MISMATCH -- * BADCERT_NOT_TRUSTED * or another error in case of a fatal error encountered * during the verification process. */ int x509_crt_verify( x509_crt *crt, x509_crt *trust_ca, x509_crl *ca_crl, const char *cn, int *flags, int (*f_vrfy)(void *, x509_crt *, int, int *), void *p_vrfy ); #if defined(POLARSSL_X509_CHECK_KEY_USAGE) /** * \brief Check usage of certificate against keyUsage extension. * * \param crt Leaf certificate used. * \param usage Intended usage(s) (eg KU_KEY_ENCIPHERMENT before using the * certificate to perform an RSA key exchange). * * \return 0 is these uses of the certificate are allowed, * POLARSSL_ERR_X509_BAD_INPUT_DATA if the keyUsage extension * is present but does not contain all the bits set in the * usage argument. * * \note You should only call this function on leaf certificates, on * (intermediate) CAs the keyUsage extension is automatically * checked by \c x509_crt_verify(). */ int x509_crt_check_key_usage( const x509_crt *crt, int usage ); #endif /* POLARSSL_X509_CHECK_KEY_USAGE) */ #if defined(POLARSSL_X509_CRL_PARSE_C) /** * \brief Verify the certificate revocation status * * \param crt a certificate to be verified * \param crl the CRL to verify against * * \return 1 if the certificate is revoked, 0 otherwise * */ int x509_crt_revoked( const x509_crt *crt, const x509_crl *crl ); #endif /* POLARSSL_X509_CRL_PARSE_C */ /** * \brief Initialize a certificate (chain) * * \param crt Certificate chain to initialize */ void x509_crt_init( x509_crt *crt ); /** * \brief Unallocate all certificate data * * \param crt Certificate chain to free */ void x509_crt_free( x509_crt *crt ); #endif /* POLARSSL_X509_CRT_PARSE_C */ /* \} name */ /* \} addtogroup x509_module */ #if defined(POLARSSL_X509_CRT_WRITE_C) /** * \brief Initialize a CRT writing context * * \param ctx CRT context to initialize */ void x509write_crt_init( x509write_cert *ctx ); /** * \brief Set the verion for a Certificate * Default: X509_CRT_VERSION_3 * * \param ctx CRT context to use * \param version version to set (X509_CRT_VERSION_1, X509_CRT_VERSION_2 or * X509_CRT_VERSION_3) */ void x509write_crt_set_version( x509write_cert *ctx, int version ); /** * \brief Set the serial number for a Certificate. * * \param ctx CRT context to use * \param serial serial number to set * * \return 0 if successful */ int x509write_crt_set_serial( x509write_cert *ctx, const mpi *serial ); /** * \brief Set the validity period for a Certificate * Timestamps should be in string format for UTC timezone * i.e. "YYYYMMDDhhmmss" * e.g. "20131231235959" for December 31st 2013 * at 23:59:59 * * \param ctx CRT context to use * \param not_before not_before timestamp * \param not_after not_after timestamp * * \return 0 if timestamp was parsed successfully, or * a specific error code */ int x509write_crt_set_validity( x509write_cert *ctx, const char *not_before, const char *not_after ); /** * \brief Set the issuer name for a Certificate * Issuer names should contain a comma-separated list * of OID types and values: * e.g. "C=NL,O=Offspark,CN=PolarSSL CA" * * \param ctx CRT context to use * \param issuer_name issuer name to set * * \return 0 if issuer name was parsed successfully, or * a specific error code */ int x509write_crt_set_issuer_name( x509write_cert *ctx, const char *issuer_name ); /** * \brief Set the subject name for a Certificate * Subject names should contain a comma-separated list * of OID types and values: * e.g. "C=NL,O=Offspark,CN=PolarSSL Server 1" * * \param ctx CRT context to use * \param subject_name subject name to set * * \return 0 if subject name was parsed successfully, or * a specific error code */ int x509write_crt_set_subject_name( x509write_cert *ctx, const char *subject_name ); /** * \brief Set the subject public key for the certificate * * \param ctx CRT context to use * \param key public key to include */ void x509write_crt_set_subject_key( x509write_cert *ctx, pk_context *key ); /** * \brief Set the issuer key used for signing the certificate * * \param ctx CRT context to use * \param key private key to sign with */ void x509write_crt_set_issuer_key( x509write_cert *ctx, pk_context *key ); /** * \brief Set the MD algorithm to use for the signature * (e.g. POLARSSL_MD_SHA1) * * \param ctx CRT context to use * \param md_alg MD algorithm to use */ void x509write_crt_set_md_alg( x509write_cert *ctx, md_type_t md_alg ); /** * \brief Generic function to add to or replace an extension in the * CRT * * \param ctx CRT context to use * \param oid OID of the extension * \param oid_len length of the OID * \param critical if the extension is critical (per the RFC's definition) * \param val value of the extension OCTET STRING * \param val_len length of the value data * * \return 0 if successful, or a POLARSSL_ERR_X509WRITE_MALLOC_FAILED */ int x509write_crt_set_extension( x509write_cert *ctx, const char *oid, size_t oid_len, int critical, const unsigned char *val, size_t val_len ); /** * \brief Set the basicConstraints extension for a CRT * * \param ctx CRT context to use * \param is_ca is this a CA certificate * \param max_pathlen maximum length of certificate chains below this * certificate (only for CA certificates, -1 is * inlimited) * * \return 0 if successful, or a POLARSSL_ERR_X509WRITE_MALLOC_FAILED */ int x509write_crt_set_basic_constraints( x509write_cert *ctx, int is_ca, int max_pathlen ); #if defined(POLARSSL_SHA1_C) /** * \brief Set the subjectKeyIdentifier extension for a CRT * Requires that x509write_crt_set_subject_key() has been * called before * * \param ctx CRT context to use * * \return 0 if successful, or a POLARSSL_ERR_X509WRITE_MALLOC_FAILED */ int x509write_crt_set_subject_key_identifier( x509write_cert *ctx ); /** * \brief Set the authorityKeyIdentifier extension for a CRT * Requires that x509write_crt_set_issuer_key() has been * called before * * \param ctx CRT context to use * * \return 0 if successful, or a POLARSSL_ERR_X509WRITE_MALLOC_FAILED */ int x509write_crt_set_authority_key_identifier( x509write_cert *ctx ); #endif /* POLARSSL_SHA1_C */ /** * \brief Set the Key Usage Extension flags * (e.g. KU_DIGITAL_SIGNATURE | KU_KEY_CERT_SIGN) * * \param ctx CRT context to use * \param key_usage key usage flags to set * * \return 0 if successful, or POLARSSL_ERR_X509WRITE_MALLOC_FAILED */ int x509write_crt_set_key_usage( x509write_cert *ctx, unsigned char key_usage ); /** * \brief Set the Netscape Cert Type flags * (e.g. NS_CERT_TYPE_SSL_CLIENT | NS_CERT_TYPE_EMAIL) * * \param ctx CRT context to use * \param ns_cert_type Netscape Cert Type flags to set * * \return 0 if successful, or POLARSSL_ERR_X509WRITE_MALLOC_FAILED */ int x509write_crt_set_ns_cert_type( x509write_cert *ctx, unsigned char ns_cert_type ); /** * \brief Free the contents of a CRT write context * * \param ctx CRT context to free */ void x509write_crt_free( x509write_cert *ctx ); /** * \brief Write a built up certificate to a X509 DER structure * Note: data is written at the end of the buffer! Use the * return value to determine where you should start * using the buffer * * \param ctx certificate to write away * \param buf buffer to write to * \param size size of the buffer * \param f_rng RNG function (for signature, see note) * \param p_rng RNG parameter * * \return length of data written if successful, or a specific * error code * * \note f_rng may be NULL if RSA is used for signature and the * signature is made offline (otherwise f_rng is desirable * for countermeasures against timing attacks). * ECDSA signatures always require a non-NULL f_rng. */ int x509write_crt_der( x509write_cert *ctx, unsigned char *buf, size_t size, int (*f_rng)(void *, unsigned char *, size_t), void *p_rng ); #if defined(POLARSSL_PEM_WRITE_C) /** * \brief Write a built up certificate to a X509 PEM string * * \param ctx certificate to write away * \param buf buffer to write to * \param size size of the buffer * \param f_rng RNG function (for signature, see note) * \param p_rng RNG parameter * * \return 0 successful, or a specific error code * * \note f_rng may be NULL if RSA is used for signature and the * signature is made offline (otherwise f_rng is desirable * for countermeasures against timing attacks). * ECDSA signatures always require a non-NULL f_rng. */ int x509write_crt_pem( x509write_cert *ctx, unsigned char *buf, size_t size, int (*f_rng)(void *, unsigned char *, size_t), void *p_rng ); #endif /* POLARSSL_PEM_WRITE_C */ #endif /* POLARSSL_X509_CRT_WRITE_C */ #ifdef __cplusplus } #endif #endif /* x509_crt.h */