void asn1show(int depth, struct asn1struct *certificate) {
struct asn1struct *token;
int i;
token = certificate;
while (token) {
for (i = 0; i < depth; i++) {
printf(" ");
}
if (token->tag_class == ASN1_CLASS_UNIVERSAL) {
printf("%s", tag_names[token->tag]);
} else if (token->tag_class == ASN1_CLASS_APPLICATION) {
printf("application");
} else if (token->tag_class == ASN1_CLASS_SPECIFIC) {
printf("context");
} else if (token->tag_class == ASN1_CLASS_PRIVATE) {
printf("private");
}
printf( " (%d:%d) ", token->tag, token->length );
if (token->tag_class == ASN1_CLASS_UNIVERSAL) {
if (token->tag == ASN1_BIT_STRING || \
token->tag == ASN1_OCTET_STRING || \
token->tag == ASN1_OBJECT_IDENTIFIER ) {
int i;
for (i = 0; i < token->length; i++) {
printf("%.02x ", token->data[i]);
}
} else if (token->tag == ASN1_NUMERIC_STRING || \
token->tag == ASN1_PRINTABLE_STRING || \
token->tag == ASN1_VIDEOTEX_STRING || \
token->tag == ASN1_IA5_STRING || \
token->tag == ASN1_UTC_TIME || \
token->tag == ASN1_GENERALIZED_TIME || \
token->tag == ASN1_GRAPHIC_STRING || \
token->tag == ASN1_VISIBLE_STRING || \
token->tag == ASN1_GENERAL_STRING || \
token->tag == ASN1_UNIVERSAL_STRING || \
token->tag == ASN1_CHARACTER_STRING || \
token->tag == ASN1_BMP_STRING || \
token->tag == ASN1_UTF8_STRING ) {
char *str_val = (char*) malloc(token->length + 1);
strncpy(str_val, (char *) token->data, token->length);
str_val[token->length] = 0;
printf(" %s", str_val);
free(str_val);
}
}
}
printf("\n");
if (token->children) {
asn1show(depth + 1, token->children);
}
token = token->next;
}
int main( int argc, char *argv[ ] )
{
int certificate_file;
struct stat certificate_file_stat;
unsigned char *buffer, *bufptr;
int buffer_size;
int bytes_read;
struct asn1struct certificate;
if ( argc < 3 )
{
fprintf( stderr, "Usage: %s [-der|-pem] <certificate file>\n", argv[ 0 ] );
exit( 0 );
}
if ( ( certificate_file = open( argv[ 2 ], O_RDONLY ) ) == -1 )
{
perror( "Unable to open certificate file" );
return 1;
}
// Slurp the whole thing into memory
if ( fstat( certificate_file, &certificate_file_stat ) )
{
perror( "Unable to stat certificate file" );
return 2;
}
buffer_size = certificate_file_stat.st_size;
buffer = ( char * ) malloc( buffer_size );
if ( !buffer )
{
perror( "Not enough memory" );
return 3;
}
bufptr = buffer;
while ( bytes_read = read( certificate_file, ( void * ) buffer,
certificate_file_stat.st_size ) )
{
bufptr += bytes_read;
}
if ( !( strcmp( argv[ 1 ], "-pem" ) ) )
{
// XXX this overallocates a bit, since it sets aside space for markers, etc.
unsigned char *pem_buffer = buffer;
buffer = (unsigned char * ) malloc( buffer_size );
buffer_size = pem_decode( pem_buffer, buffer );
free( pem_buffer );
}
asn1parse( buffer, buffer_size, &certificate );
asn1show( 0, &certificate );
asn1free( &certificate );
return 0;
}