text: /*
   *  X.509 common functions for parsing and verification
   *
   *  Copyright (C) 2006-2015, ARM Limited, All Rights Reserved
   *  SPDX-License-Identifier: Apache-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.
   *
   *  This file is part of mbed TLS (https://tls.mbed.org)
   */
  /*
   *  The ITU-T X.509 standard defines a certificate format for PKI.
   *
   *  http://www.ietf.org/rfc/rfc5280.txt (Certificates and CRLs)
   *  http://www.ietf.org/rfc/rfc3279.txt (Alg IDs for CRLs)
   *  http://www.ietf.org/rfc/rfc2986.txt (CSRs, aka PKCS#10)
   *
   *  http://www.itu.int/ITU-T/studygroups/com17/languages/X.680-0207.pdf
   *  http://www.itu.int/ITU-T/studygroups/com17/languages/X.690-0207.pdf
   */
  
  #if !defined(MBEDTLS_CONFIG_FILE)
  #include "../include/mbedtls/config.h"
  #else
  #include MBEDTLS_CONFIG_FILE
  #endif
  
  #if defined(MBEDTLS_X509_USE_C)
  
  #include "../include/mbedtls/x509.h"
  #include "../include/mbedtls/asn1.h"
  #include "../include/mbedtls/oid.h"
  
  #include <stdio.h>
  #include <string.h>
  
  #if defined(MBEDTLS_PEM_PARSE_C)
  #include "../include/mbedtls/pem.h"
  #endif
  
  #if defined(MBEDTLS_PLATFORM_C)
  #include "../include/mbedtls/platform.h"
  #else
  #include <stdio.h>
  #include <stdlib.h>
  #define mbedtls_free      free
  #define mbedtls_calloc    calloc
  #define mbedtls_printf    printf
  #define mbedtls_snprintf  snprintf
  #endif
  
  #if defined(MBEDTLS_HAVE_TIME)
  #include "../include/mbedtls/platform_time.h"
  #endif
  #if defined(MBEDTLS_HAVE_TIME_DATE)
  #include "../include/mbedtls/platform_util.h"
  #include <time.h>
  #endif
  
  #define CHECK(code) if( ( ret = code ) != 0 ){ return( ret ); }
  #define CHECK_RANGE(min, max, val) if( val < min || val > max ){ return( ret ); }
  
  /*
   *  CertificateSerialNumber  ::=  INTEGER
   */
  int mbedtls_x509_get_serial( unsigned char **p, const unsigned char *end,
                       mbedtls_x509_buf *serial )
  {
      int ret;
  
      if( ( end - *p ) < 1 )
          return( MBEDTLS_ERR_X509_INVALID_SERIAL +
                  MBEDTLS_ERR_ASN1_OUT_OF_DATA );
  
      if( **p != ( MBEDTLS_ASN1_CONTEXT_SPECIFIC | MBEDTLS_ASN1_PRIMITIVE | 2 ) &&
          **p !=   MBEDTLS_ASN1_INTEGER )
          return( MBEDTLS_ERR_X509_INVALID_SERIAL +
                  MBEDTLS_ERR_ASN1_UNEXPECTED_TAG );
  
      serial->tag = *(*p)++;
  
      if( ( ret = mbedtls_asn1_get_len( p, end, &serial->len ) ) != 0 )
          return( MBEDTLS_ERR_X509_INVALID_SERIAL + ret );
  
      serial->p = *p;
      *p += serial->len;
  
      return( 0 );
  }
  
  /* Get an algorithm identifier without parameters (eg for signatures)
   *
   *  AlgorithmIdentifier  ::=  SEQUENCE  {
   *       algorithm               OBJECT IDENTIFIER,
   *       parameters              ANY DEFINED BY algorithm OPTIONAL  }
   */
  int mbedtls_x509_get_alg_null( unsigned char **p, const unsigned char *end,
                         mbedtls_x509_buf *alg )
  {
      int ret;
  
      if( ( ret = mbedtls_asn1_get_alg_null( p, end, alg ) ) != 0 )
          return( MBEDTLS_ERR_X509_INVALID_ALG + ret );
  
      return( 0 );
  }
  
  /*
   * Parse an algorithm identifier with (optional) paramaters
   */
  int mbedtls_x509_get_alg( unsigned char **p, const unsigned char *end,
                    mbedtls_x509_buf *alg, mbedtls_x509_buf *params )
  {
      int ret;
  
      if( ( ret = mbedtls_asn1_get_alg( p, end, alg, params ) ) != 0 )
          return( MBEDTLS_ERR_X509_INVALID_ALG + ret );
  
      return( 0 );
  }
  
  #if defined(MBEDTLS_X509_RSASSA_PSS_SUPPORT)
  /*
   * HashAlgorithm ::= AlgorithmIdentifier
   *
   * AlgorithmIdentifier  ::=  SEQUENCE  {
   *      algorithm               OBJECT IDENTIFIER,
   *      parameters              ANY DEFINED BY algorithm OPTIONAL  }
   *
   * For HashAlgorithm, parameters MUST be NULL or absent.
   */
  static int x509_get_hash_alg( const mbedtls_x509_buf *alg, mbedtls_md_type_t *md_alg )
  {
      int ret;
      unsigned char *p;
      const unsigned char *end;
      mbedtls_x509_buf md_oid;
      size_t len;
  
      /* Make sure we got a SEQUENCE and setup bounds */
      if( alg->tag != ( MBEDTLS_ASN1_CONSTRUCTED | MBEDTLS_ASN1_SEQUENCE ) )
          return( MBEDTLS_ERR_X509_INVALID_ALG +
                  MBEDTLS_ERR_ASN1_UNEXPECTED_TAG );
  
      p = (unsigned char *) alg->p;
      end = p + alg->len;
  
      if( p >= end )
          return( MBEDTLS_ERR_X509_INVALID_ALG +
                  MBEDTLS_ERR_ASN1_OUT_OF_DATA );
  
      /* Parse md_oid */
      md_oid.tag = *p;
  
      if( ( ret = mbedtls_asn1_get_tag( &p, end, &md_oid.len, MBEDTLS_ASN1_OID ) ) != 0 )
          return( MBEDTLS_ERR_X509_INVALID_ALG + ret );
  
      md_oid.p = p;
      p += md_oid.len;
  
      /* Get md_alg from md_oid */
      if( ( ret = mbedtls_oid_get_md_alg( &md_oid, md_alg ) ) != 0 )
          return( MBEDTLS_ERR_X509_INVALID_ALG + ret );
  
      /* Make sure params is absent of NULL */
      if( p == end )
          return( 0 );
  
      if( ( ret = mbedtls_asn1_get_tag( &p, end, &len, MBEDTLS_ASN1_NULL ) ) != 0 || len != 0 )
          return( MBEDTLS_ERR_X509_INVALID_ALG + ret );
  
      if( p != end )
          return( MBEDTLS_ERR_X509_INVALID_ALG +
                  MBEDTLS_ERR_ASN1_LENGTH_MISMATCH );
  
      return( 0 );
  }
  
  /*
   *    RSASSA-PSS-params  ::=  SEQUENCE  {
   *       hashAlgorithm     [0] HashAlgorithm DEFAULT sha1Identifier,
   *       maskGenAlgorithm  [1] MaskGenAlgorithm DEFAULT mgf1SHA1Identifier,
   *       saltLength        [2] INTEGER DEFAULT 20,
   *       trailerField      [3] INTEGER DEFAULT 1  }
   *    -- Note that the tags in this Sequence are explicit.
   *
   * RFC 4055 (which defines use of RSASSA-PSS in PKIX) states that the value
   * of trailerField MUST be 1, and PKCS#1 v2.2 doesn't even define any other
   * option. Enfore this at parsing time.
   */
  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 )
  {
      int ret;
      unsigned char *p;
      const unsigned char *end, *end2;
      size_t len;
      mbedtls_x509_buf alg_id, alg_params;
  
      /* First set everything to defaults */
      *md_alg = MBEDTLS_MD_SHA1;
      *mgf_md = MBEDTLS_MD_SHA1;
      *salt_len = 20;
  
      /* Make sure params is a SEQUENCE and setup bounds */
      if( params->tag != ( MBEDTLS_ASN1_CONSTRUCTED | MBEDTLS_ASN1_SEQUENCE ) )
          return( MBEDTLS_ERR_X509_INVALID_ALG +
                  MBEDTLS_ERR_ASN1_UNEXPECTED_TAG );
  
      p = (unsigned char *) params->p;
      end = p + params->len;
  
      if( p == end )
          return( 0 );
  
      /*
       * HashAlgorithm
       */
      if( ( ret = mbedtls_asn1_get_tag( &p, end, &len,
                      MBEDTLS_ASN1_CONTEXT_SPECIFIC | MBEDTLS_ASN1_CONSTRUCTED | 0 ) ) == 0 )
      {
          end2 = p + len;
  
          /* HashAlgorithm ::= AlgorithmIdentifier (without parameters) */
          if( ( ret = mbedtls_x509_get_alg_null( &p, end2, &alg_id ) ) != 0 )
              return( ret );
  
          if( ( ret = mbedtls_oid_get_md_alg( &alg_id, md_alg ) ) != 0 )
              return( MBEDTLS_ERR_X509_INVALID_ALG + ret );
  
          if( p != end2 )
              return( MBEDTLS_ERR_X509_INVALID_ALG +
                      MBEDTLS_ERR_ASN1_LENGTH_MISMATCH );
      }
      else if( ret != MBEDTLS_ERR_ASN1_UNEXPECTED_TAG )
          return( MBEDTLS_ERR_X509_INVALID_ALG + ret );
  
      if( p == end )
          return( 0 );
  
      /*
       * MaskGenAlgorithm
       */
      if( ( ret = mbedtls_asn1_get_tag( &p, end, &len,
                      MBEDTLS_ASN1_CONTEXT_SPECIFIC | MBEDTLS_ASN1_CONSTRUCTED | 1 ) ) == 0 )
      {
          end2 = p + len;
  
          /* MaskGenAlgorithm ::= AlgorithmIdentifier (params = HashAlgorithm) */
          if( ( ret = mbedtls_x509_get_alg( &p, end2, &alg_id, &alg_params ) ) != 0 )
              return( ret );
  
          /* Only MFG1 is recognised for now */
          if( MBEDTLS_OID_CMP( MBEDTLS_OID_MGF1, &alg_id ) != 0 )
              return( MBEDTLS_ERR_X509_FEATURE_UNAVAILABLE +
                      MBEDTLS_ERR_OID_NOT_FOUND );
  
          /* Parse HashAlgorithm */
          if( ( ret = x509_get_hash_alg( &alg_params, mgf_md ) ) != 0 )
              return( ret );
  
          if( p != end2 )
              return( MBEDTLS_ERR_X509_INVALID_ALG +
                      MBEDTLS_ERR_ASN1_LENGTH_MISMATCH );
      }
      else if( ret != MBEDTLS_ERR_ASN1_UNEXPECTED_TAG )
          return( MBEDTLS_ERR_X509_INVALID_ALG + ret );
  
      if( p == end )
          return( 0 );
  
      /*
       * salt_len
       */
      if( ( ret = mbedtls_asn1_get_tag( &p, end, &len,
                      MBEDTLS_ASN1_CONTEXT_SPECIFIC | MBEDTLS_ASN1_CONSTRUCTED | 2 ) ) == 0 )
      {
          end2 = p + len;
  
          if( ( ret = mbedtls_asn1_get_int( &p, end2, salt_len ) ) != 0 )
              return( MBEDTLS_ERR_X509_INVALID_ALG + ret );
  
          if( p != end2 )
              return( MBEDTLS_ERR_X509_INVALID_ALG +
                      MBEDTLS_ERR_ASN1_LENGTH_MISMATCH );
      }
      else if( ret != MBEDTLS_ERR_ASN1_UNEXPECTED_TAG )
          return( MBEDTLS_ERR_X509_INVALID_ALG + ret );
  
      if( p == end )
          return( 0 );
  
      /*
       * trailer_field (if present, must be 1)
       */
      if( ( ret = mbedtls_asn1_get_tag( &p, end, &len,
                      MBEDTLS_ASN1_CONTEXT_SPECIFIC | MBEDTLS_ASN1_CONSTRUCTED | 3 ) ) == 0 )
      {
          int trailer_field;
  
          end2 = p + len;
  
          if( ( ret = mbedtls_asn1_get_int( &p, end2, &trailer_field ) ) != 0 )
              return( MBEDTLS_ERR_X509_INVALID_ALG + ret );
  
          if( p != end2 )
              return( MBEDTLS_ERR_X509_INVALID_ALG +
                      MBEDTLS_ERR_ASN1_LENGTH_MISMATCH );
  
          if( trailer_field != 1 )
              return( MBEDTLS_ERR_X509_INVALID_ALG );
      }
      else if( ret != MBEDTLS_ERR_ASN1_UNEXPECTED_TAG )
          return( MBEDTLS_ERR_X509_INVALID_ALG + ret );
  
      if( p != end )
          return( MBEDTLS_ERR_X509_INVALID_ALG +
                  MBEDTLS_ERR_ASN1_LENGTH_MISMATCH );
  
      return( 0 );
  }
  #endif /* MBEDTLS_X509_RSASSA_PSS_SUPPORT */
  
  /*
   *  AttributeTypeAndValue ::= SEQUENCE {
   *    type     AttributeType,
   *    value    AttributeValue }
   *
   *  AttributeType ::= OBJECT IDENTIFIER
   *
   *  AttributeValue ::= ANY DEFINED BY AttributeType
   */
  static int x509_get_attr_type_value( unsigned char **p,
                                       const unsigned char *end,
                                       mbedtls_x509_name *cur )
  {
      int ret;
      size_t len;
      mbedtls_x509_buf *oid;
      mbedtls_x509_buf *val;
  
      if( ( ret = mbedtls_asn1_get_tag( p, end, &len,
              MBEDTLS_ASN1_CONSTRUCTED | MBEDTLS_ASN1_SEQUENCE ) ) != 0 )
          return( MBEDTLS_ERR_X509_INVALID_NAME + ret );
  
      if( ( end - *p ) < 1 )
          return( MBEDTLS_ERR_X509_INVALID_NAME +
                  MBEDTLS_ERR_ASN1_OUT_OF_DATA );
  
      oid = &cur->oid;
      oid->tag = **p;
  
      if( ( ret = mbedtls_asn1_get_tag( p, end, &oid->len, MBEDTLS_ASN1_OID ) ) != 0 )
          return( MBEDTLS_ERR_X509_INVALID_NAME + ret );
  
      oid->p = *p;
      *p += oid->len;
  
      if( ( end - *p ) < 1 )
          return( MBEDTLS_ERR_X509_INVALID_NAME +
                  MBEDTLS_ERR_ASN1_OUT_OF_DATA );
  
      if( **p != MBEDTLS_ASN1_BMP_STRING && **p != MBEDTLS_ASN1_UTF8_STRING      &&
          **p != MBEDTLS_ASN1_T61_STRING && **p != MBEDTLS_ASN1_PRINTABLE_STRING &&
          **p != MBEDTLS_ASN1_IA5_STRING && **p != MBEDTLS_ASN1_UNIVERSAL_STRING &&
          **p != MBEDTLS_ASN1_BIT_STRING )
          return( MBEDTLS_ERR_X509_INVALID_NAME +
                  MBEDTLS_ERR_ASN1_UNEXPECTED_TAG );
  
      val = &cur->val;
      val->tag = *(*p)++;
  
      if( ( ret = mbedtls_asn1_get_len( p, end, &val->len ) ) != 0 )
          return( MBEDTLS_ERR_X509_INVALID_NAME + ret );
  
      val->p = *p;
      *p += val->len;
  
      cur->next = NULL;
  
      return( 0 );
  }
  
  /*
   *  Name ::= CHOICE { -- only one possibility for now --
   *       rdnSequence  RDNSequence }
   *
   *  RDNSequence ::= SEQUENCE OF RelativeDistinguishedName
   *
   *  RelativeDistinguishedName ::=
   *    SET OF AttributeTypeAndValue
   *
   *  AttributeTypeAndValue ::= SEQUENCE {
   *    type     AttributeType,
   *    value    AttributeValue }
   *
   *  AttributeType ::= OBJECT IDENTIFIER
   *
   *  AttributeValue ::= ANY DEFINED BY AttributeType
   *
   * The data structure is optimized for the common case where each RDN has only
   * one element, which is represented as a list of AttributeTypeAndValue.
   * For the general case we still use a flat list, but we mark elements of the
   * same set so that they are "merged" together in the functions that consume
   * this list, eg mbedtls_x509_dn_gets().
   */
  int mbedtls_x509_get_name( unsigned char **p, const unsigned char *end,
                     mbedtls_x509_name *cur )
  {
      int ret;
      size_t set_len;
      const unsigned char *end_set;
  
      /* don't use recursion, we'd risk stack overflow if not optimized */
      while( 1 )
      {
          /*
           * parse SET
           */
          if( ( ret = mbedtls_asn1_get_tag( p, end, &set_len,
                  MBEDTLS_ASN1_CONSTRUCTED | MBEDTLS_ASN1_SET ) ) != 0 )
              return( MBEDTLS_ERR_X509_INVALID_NAME + ret );
  
          end_set  = *p + set_len;
  
          while( 1 )
          {
              if( ( ret = x509_get_attr_type_value( p, end_set, cur ) ) != 0 )
                  return( ret );
  
              if( *p == end_set )
                  break;
  
              /* Mark this item as being no the only one in a set */
              cur->next_merged = 1;
  
              cur->next = mbedtls_calloc( 1, sizeof( mbedtls_x509_name ) );
  
              if( cur->next == NULL )
                  return( MBEDTLS_ERR_X509_ALLOC_FAILED );
  
              cur = cur->next;
          }
  
          /*
           * continue until end of SEQUENCE is reached
           */
          if( *p == end )
              return( 0 );
  
          cur->next = mbedtls_calloc( 1, sizeof( mbedtls_x509_name ) );
  
          if( cur->next == NULL )
              return( MBEDTLS_ERR_X509_ALLOC_FAILED );
  
          cur = cur->next;
      }
  }
  
  static int x509_parse_int( unsigned char **p, size_t n, int *res )
  {
      *res = 0;
  
      for( ; n > 0; --n )
      {
          if( ( **p < '0') || ( **p > '9' ) )
              return ( MBEDTLS_ERR_X509_INVALID_DATE );
  
          *res *= 10;
          *res += ( *(*p)++ - '0' );
      }
  
      return( 0 );
  }
  
  static int x509_date_is_valid(const mbedtls_x509_time *t )
  {
      int ret = MBEDTLS_ERR_X509_INVALID_DATE;
      int month_len;
  
      CHECK_RANGE( 0, 9999, t->year );
      CHECK_RANGE( 0, 23,   t->hour );
      CHECK_RANGE( 0, 59,   t->min  );
      CHECK_RANGE( 0, 59,   t->sec  );
  
      switch( t->mon )
      {
          case 1: case 3: case 5: case 7: case 8: case 10: case 12:
              month_len = 31;
              break;
          case 4: case 6: case 9: case 11:
              month_len = 30;
              break;
          case 2:
              if( ( !( t->year % 4 ) && t->year % 100 ) ||
                  !( t->year % 400 ) )
                  month_len = 29;
              else
                  month_len = 28;
              break;
          default:
              return( ret );
      }
      CHECK_RANGE( 1, month_len, t->day );
  
      return( 0 );
  }
  
  /*
   * Parse an ASN1_UTC_TIME (yearlen=2) or ASN1_GENERALIZED_TIME (yearlen=4)
   * field.
   */
  static int x509_parse_time( unsigned char **p, size_t len, size_t yearlen,
                              mbedtls_x509_time *tm )
  {
      int ret;
  
      /*
       * Minimum length is 10 or 12 depending on yearlen
       */
      if ( len < yearlen + 8 )
          return ( MBEDTLS_ERR_X509_INVALID_DATE );
      len -= yearlen + 8;
  
      /*
       * Parse year, month, day, hour, minute
       */
      CHECK( x509_parse_int( p, yearlen, &tm->year ) );
      if ( 2 == yearlen )
      {
          if ( tm->year < 50 )
              tm->year += 100;
  
          tm->year += 1900;
      }
  
      CHECK( x509_parse_int( p, 2, &tm->mon ) );
      CHECK( x509_parse_int( p, 2, &tm->day ) );
      CHECK( x509_parse_int( p, 2, &tm->hour ) );
      CHECK( x509_parse_int( p, 2, &tm->min ) );
  
      /*
       * Parse seconds if present
       */
      if ( len >= 2 )
      {
          CHECK( x509_parse_int( p, 2, &tm->sec ) );
          len -= 2;
      }
      else
          return ( MBEDTLS_ERR_X509_INVALID_DATE );
  
      /*
       * Parse trailing 'Z' if present
       */
      if ( 1 == len && 'Z' == **p )
      {
          (*p)++;
          len--;
      }
  
      /*
       * We should have parsed all characters at this point
       */
      if ( 0 != len )
          return ( MBEDTLS_ERR_X509_INVALID_DATE );
  
      CHECK( x509_date_is_valid( tm ) );
  
      return ( 0 );
  }
  
  /*
   *  Time ::= CHOICE {
   *       utcTime        UTCTime,
   *       generalTime    GeneralizedTime }
   */
  int mbedtls_x509_get_time( unsigned char **p, const unsigned char *end,
                             mbedtls_x509_time *tm )
  {
      int ret;
      size_t len, year_len;
      unsigned char tag;
  
      if( ( end - *p ) < 1 )
          return( MBEDTLS_ERR_X509_INVALID_DATE +
                  MBEDTLS_ERR_ASN1_OUT_OF_DATA );
  
      tag = **p;
  
      if( tag == MBEDTLS_ASN1_UTC_TIME )
          year_len = 2;
      else if( tag == MBEDTLS_ASN1_GENERALIZED_TIME )
          year_len = 4;
      else
          return( MBEDTLS_ERR_X509_INVALID_DATE +
                  MBEDTLS_ERR_ASN1_UNEXPECTED_TAG );
  
      (*p)++;
      ret = mbedtls_asn1_get_len( p, end, &len );
  
      if( ret != 0 )
          return( MBEDTLS_ERR_X509_INVALID_DATE + ret );
  
      return x509_parse_time( p, len, year_len, tm );
  }
  
  int mbedtls_x509_get_sig( unsigned char **p, const unsigned char *end, mbedtls_x509_buf *sig )
  {
      int ret;
      size_t len;
      int tag_type;
  
      if( ( end - *p ) < 1 )
          return( MBEDTLS_ERR_X509_INVALID_SIGNATURE +
                  MBEDTLS_ERR_ASN1_OUT_OF_DATA );
  
      tag_type = **p;
  
      if( ( ret = mbedtls_asn1_get_bitstring_null( p, end, &len ) ) != 0 )
          return( MBEDTLS_ERR_X509_INVALID_SIGNATURE + ret );
  
      sig->tag = tag_type;
      sig->len = len;
      sig->p = *p;
  
      *p += len;
  
      return( 0 );
  }
  
  /*
   * Get signature algorithm from alg OID and optional parameters
   */
  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 ret;
  
      if( *sig_opts != NULL )
          return( MBEDTLS_ERR_X509_BAD_INPUT_DATA );
  
      if( ( ret = mbedtls_oid_get_sig_alg( sig_oid, md_alg, pk_alg ) ) != 0 )
          return( MBEDTLS_ERR_X509_UNKNOWN_SIG_ALG + ret );
  
  #if defined(MBEDTLS_X509_RSASSA_PSS_SUPPORT)
      if( *pk_alg == MBEDTLS_PK_RSASSA_PSS )
      {
          mbedtls_pk_rsassa_pss_options *pss_opts;
  
          pss_opts = mbedtls_calloc( 1, sizeof( mbedtls_pk_rsassa_pss_options ) );
          if( pss_opts == NULL )
              return( MBEDTLS_ERR_X509_ALLOC_FAILED );
  
          ret = mbedtls_x509_get_rsassa_pss_params( sig_params,
                                            md_alg,
                                            &pss_opts->mgf1_hash_id,
                                            &pss_opts->expected_salt_len );
          if( ret != 0 )
          {
              mbedtls_free( pss_opts );
              return( ret );
          }
  
          *sig_opts = (void *) pss_opts;
      }
      else
  #endif /* MBEDTLS_X509_RSASSA_PSS_SUPPORT */
      {
          /* Make sure parameters are absent or NULL */
          if( ( sig_params->tag != MBEDTLS_ASN1_NULL && sig_params->tag != 0 ) ||
                sig_params->len != 0 )
          return( MBEDTLS_ERR_X509_INVALID_ALG );
      }
  
      return( 0 );
  }
  
  /*
   * X.509 Extensions (No parsing of extensions, pointer should
   * be either manually updated or extensions should be parsed!)
   */
  int mbedtls_x509_get_ext( unsigned char **p, const unsigned char *end,
                    mbedtls_x509_buf *ext, int tag )
  {
      int ret;
      size_t len;
  
      if( *p == end )
          return( 0 );
  
      ext->tag = **p;
  
      if( ( ret = mbedtls_asn1_get_tag( p, end, &ext->len,
              MBEDTLS_ASN1_CONTEXT_SPECIFIC | MBEDTLS_ASN1_CONSTRUCTED | tag ) ) != 0 )
          return( ret );
  
      ext->p = *p;
      end = *p + ext->len;
  
      /*
       * Extensions  ::=  SEQUENCE SIZE (1..MAX) OF Extension
       *
       * Extension  ::=  SEQUENCE  {
       *      extnID      OBJECT IDENTIFIER,
       *      critical    BOOLEAN DEFAULT FALSE,
       *      extnValue   OCTET STRING  }
       */
      if( ( ret = mbedtls_asn1_get_tag( p, end, &len,
              MBEDTLS_ASN1_CONSTRUCTED | MBEDTLS_ASN1_SEQUENCE ) ) != 0 )
          return( MBEDTLS_ERR_X509_INVALID_EXTENSIONS + ret );
  
      if( end != *p + len )
          return( MBEDTLS_ERR_X509_INVALID_EXTENSIONS +
                  MBEDTLS_ERR_ASN1_LENGTH_MISMATCH );
  
      return( 0 );
  }
  
  /*
   * Store the name in printable form into buf; no more
   * than size characters will be written
   */
  int mbedtls_x509_dn_gets( char *buf, size_t size, const mbedtls_x509_name *dn )
  {
      int ret;
      size_t i, n;
      unsigned char c, merge = 0;
      const mbedtls_x509_name *name;
      const char *short_name = NULL;
      char s[MBEDTLS_X509_MAX_DN_NAME_SIZE], *p;
  
      memset( s, 0, sizeof( s ) );
  
      name = dn;
      p = buf;
      n = size;
  
      while( name != NULL )
      {
          if( !name->oid.p )
          {
              name = name->next;
              continue;
          }
  
          if( name != dn )
          {
              ret = mbedtls_snprintf( p, n, merge ? " + " : ", " );
              MBEDTLS_X509_SAFE_SNPRINTF;
          }
  
          ret = mbedtls_oid_get_attr_short_name( &name->oid, &short_name );
  
          if( ret == 0 )
              ret = mbedtls_snprintf( p, n, "%s=", short_name );
          else
              ret = mbedtls_snprintf( p, n, "\?\?=" );
          MBEDTLS_X509_SAFE_SNPRINTF;
  
          for( i = 0; i < name->val.len; i++ )
          {
              if( i >= sizeof( s ) - 1 )
                  break;
  
              c = name->val.p[i];
              if( c < 32 || c == 127 || ( c > 128 && c < 160 ) )
                   s[i] = '?';
              else s[i] = c;
          }
          s[i] = '\0';
          ret = mbedtls_snprintf( p, n, "%s", s );
          MBEDTLS_X509_SAFE_SNPRINTF;
  
          merge = name->next_merged;
          name = name->next;
      }
  
      return( (int) ( size - n ) );
  }
  
  /*
   * Store the serial in printable form into buf; no more
   * than size characters will be written
   */
  int mbedtls_x509_serial_gets( char *buf, size_t size, const mbedtls_x509_buf *serial )
  {
      int ret;
      size_t i, n, nr;
      char *p;
  
      p = buf;
      n = size;
  
      nr = ( serial->len <= 32 )
          ? serial->len  : 28;
  
      for( i = 0; i < nr; i++ )
      {
          if( i == 0 && nr > 1 && serial->p[i] == 0x0 )
              continue;
  
          ret = mbedtls_snprintf( p, n, "%02X%s",
                  serial->p[i], ( i < nr - 1 ) ? ":" : "" );
          MBEDTLS_X509_SAFE_SNPRINTF;
      }
  
      if( nr != serial->len )
      {
          ret = mbedtls_snprintf( p, n, "...." );
          MBEDTLS_X509_SAFE_SNPRINTF;
      }
  
      return( (int) ( size - n ) );
  }
  
  /*
   * Helper for writing signature algorithms
   */
  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 ret;
      char *p = buf;
      size_t n = size;
      const char *desc = NULL;
  
      ret = mbedtls_oid_get_sig_alg_desc( sig_oid, &desc );
      if( ret != 0 )
          ret = mbedtls_snprintf( p, n, "???"  );
      else
          ret = mbedtls_snprintf( p, n, "%s", desc );
      MBEDTLS_X509_SAFE_SNPRINTF;
  
  #if defined(MBEDTLS_X509_RSASSA_PSS_SUPPORT)
      if( pk_alg == MBEDTLS_PK_RSASSA_PSS )
      {
          const mbedtls_pk_rsassa_pss_options *pss_opts;
          const mbedtls_md_info_t *md_info, *mgf_md_info;
  
          pss_opts = (const mbedtls_pk_rsassa_pss_options *) sig_opts;
  
          md_info = mbedtls_md_info_from_type( md_alg );
          mgf_md_info = mbedtls_md_info_from_type( pss_opts->mgf1_hash_id );
  
          ret = mbedtls_snprintf( p, n, " (%s, MGF1-%s, 0x%02X)",
                                md_info ? mbedtls_md_get_name( md_info ) : "???",
                                mgf_md_info ? mbedtls_md_get_name( mgf_md_info ) : "???",
                                pss_opts->expected_salt_len );
          MBEDTLS_X509_SAFE_SNPRINTF;
      }
  #else
      ((void) pk_alg);
      ((void) md_alg);
      ((void) sig_opts);
  #endif /* MBEDTLS_X509_RSASSA_PSS_SUPPORT */
  
      return( (int)( size - n ) );
  }
  
  /*
   * Helper for writing "RSA key size", "EC key size", etc
   */
  int mbedtls_x509_key_size_helper( char *buf, size_t buf_size, const char *name )
  {
      char *p = buf;
      size_t n = buf_size;
      int ret;
  
      ret = mbedtls_snprintf( p, n, "%s key size", name );
      MBEDTLS_X509_SAFE_SNPRINTF;
  
      return( 0 );
  }
  
  #if defined(MBEDTLS_HAVE_TIME_DATE)
  /*
   * Set the time structure to the current time.
   * Return 0 on success, non-zero on failure.
   */
  static int x509_get_current_time( mbedtls_x509_time *now )
  {
      struct tm *lt, tm_buf;
      mbedtls_time_t tt;
      int ret = 0;
  
      tt = mbedtls_time( NULL );
      lt = mbedtls_platform_gmtime_r( &tt, &tm_buf );
  
      if( lt == NULL )
          ret = -1;
      else
      {
          now->year = lt->tm_year + 1900;
          now->mon  = lt->tm_mon  + 1;
          now->day  = lt->tm_mday;
          now->hour = lt->tm_hour;
          now->min  = lt->tm_min;
          now->sec  = lt->tm_sec;
      }
  
      return( ret );
  }
  
  /*
   * Return 0 if before <= after, 1 otherwise
   */
  static int x509_check_time( const mbedtls_x509_time *before, const mbedtls_x509_time *after )
  {
      if( before->year  > after->year )
          return( 1 );
  
      if( before->year == after->year &&
          before->mon   > after->mon )
          return( 1 );
  
      if( before->year == after->year &&
          before->mon  == after->mon  &&
          before->day   > after->day )
          return( 1 );
  
      if( before->year == after->year &&
          before->mon  == after->mon  &&
          before->day  == after->day  &&
          before->hour  > after->hour )
          return( 1 );
  
      if( before->year == after->year &&
          before->mon  == after->mon  &&
          before->day  == after->day  &&
          before->hour == after->hour &&
          before->min   > after->min  )
          return( 1 );
  
      if( before->year == after->year &&
          before->mon  == after->mon  &&
          before->day  == after->day  &&
          before->hour == after->hour &&
          before->min  == after->min  &&
          before->sec   > after->sec  )
          return( 1 );
  
      return( 0 );
  }
  
  int mbedtls_x509_time_is_past( const mbedtls_x509_time *to )
  {
      mbedtls_x509_time now;
  
      if( x509_get_current_time( &now ) != 0 )
          return( 1 );
  
      return( x509_check_time( &now, to ) );
  }
  
  int mbedtls_x509_time_is_future( const mbedtls_x509_time *from )
  {
      mbedtls_x509_time now;
  
      if( x509_get_current_time( &now ) != 0 )
          return( 1 );
  
      return( x509_check_time( from, &now ) );
  }
  
  #else  /* MBEDTLS_HAVE_TIME_DATE */
  
  int mbedtls_x509_time_is_past( const mbedtls_x509_time *to )
  {
      ((void) to);
      return( 0 );
  }
  
  int mbedtls_x509_time_is_future( const mbedtls_x509_time *from )
  {
      ((void) from);
      return( 0 );
  }
  #endif /* MBEDTLS_HAVE_TIME_DATE */
  
  #if defined(MBEDTLS_SELF_TEST)
  
  #include "../include/mbedtls/x509_crt.h"
  #include "../include/mbedtls/certs.h"
  
  /*
   * Checkup routine
   */
  int mbedtls_x509_self_test( int verbose )
  {
  #if defined(MBEDTLS_CERTS_C) && defined(MBEDTLS_SHA256_C)
      int ret;
      uint32_t flags;
      mbedtls_x509_crt cacert;
      mbedtls_x509_crt clicert;
  
      if( verbose != 0 )
          mbedtls_printf( "  X.509 certificate load: " );
  
      mbedtls_x509_crt_init( &clicert );
  
      ret = mbedtls_x509_crt_parse( &clicert, (const unsigned char *) mbedtls_test_cli_crt,
                             mbedtls_test_cli_crt_len );
      if( ret != 0 )
      {
          if( verbose != 0 )
              mbedtls_printf( "failed\n" );
  
          return( ret );
      }
  
      mbedtls_x509_crt_init( &cacert );
  
      ret = mbedtls_x509_crt_parse( &cacert, (const unsigned char *) mbedtls_test_ca_crt,
                            mbedtls_test_ca_crt_len );
      if( ret != 0 )
      {
          if( verbose != 0 )
              mbedtls_printf( "failed\n" );
  
          return( ret );
      }
  
      if( verbose != 0 )
          mbedtls_printf( "passed\n  X.509 signature verify: ");
  
      ret = mbedtls_x509_crt_verify( &clicert, &cacert, NULL, NULL, &flags, NULL, NULL );
      if( ret != 0 )
      {
          if( verbose != 0 )
              mbedtls_printf( "failed\n" );
  
          return( ret );
      }
  
      if( verbose != 0 )
          mbedtls_printf( "passed\n\n");
  
      mbedtls_x509_crt_free( &cacert  );
      mbedtls_x509_crt_free( &clicert );
  
      return( 0 );
  #else
      ((void) verbose);
      return( 0 );
  #endif /* MBEDTLS_CERTS_C && MBEDTLS_SHA1_C */
  }
  
  #endif /* MBEDTLS_SELF_TEST */
  
  #endif /* MBEDTLS_X509_USE_C */
  