1.1 --- a/src/dcload.c	Thu Jul 06 22:44:39 2006 +0000
     1.2 +++ b/src/dcload.c	Mon Jan 15 08:32:09 2007 +0000
     1.3 @@ -1,5 +1,5 @@
     1.4  /**
     1.5 - * $Id: dcload.c,v 1.5 2006-07-06 22:44:39 nkeynes Exp $
     1.6 + * $Id: dcload.c,v 1.6 2006-08-07 13:18:16 nkeynes Exp $
     1.7   * 
     1.8   * DC-load syscall implementation.
     1.9   *
    1.10 @@ -48,40 +48,104 @@
    1.11  #define SYS_MAGIC_ADDR 0x8c004004
    1.12  #define SYSCALL_ADDR 0x8c004008
    1.13  
    1.14 -static gboolean dcload_allow_exit = FALSE;
    1.15 +static gboolean dcload_allow_unsafe = FALSE;
    1.16  
    1.17 -void dcload_set_allow_exit( gboolean allow )
    1.18 +void dcload_set_allow_unsafe( gboolean allow )
    1.19  {
    1.20 -    dcload_allow_exit = allow;
    1.21 +    dcload_allow_unsafe = allow;
    1.22 +}
    1.23 +
    1.24 +#define MAX_OPEN_FDS 16
    1.25 +/**
    1.26 + * Mapping from emulator fd to real fd (so we can limit read/write
    1.27 + * to only fds we've explicitly granted access to).
    1.28 + */
    1.29 +int open_fds[MAX_OPEN_FDS];
    1.30 +
    1.31 +int dcload_alloc_fd() 
    1.32 +{
    1.33 +    int i;
    1.34 +    for( i=0; i<MAX_OPEN_FDS; i++ ) {
    1.35 +	if( open_fds[i] == -1 ) {
    1.36 +	    return i;
    1.37 +	}
    1.38 +    }
    1.39 +    return -1;
    1.40  }
    1.41  
    1.42  void dcload_syscall( uint32_t syscall_id ) 
    1.43  {
    1.44      uint32_t syscall = sh4r.r[4];
    1.45 +    int fd;
    1.46      switch( sh4r.r[4] ) {
    1.47      case SYS_READ:
    1.48 -	if( sh4r.r[5] == 0 ) {
    1.49 +	fd = sh4r.r[5];
    1.50 +	if( fd < 0 || fd >= MAX_OPEN_FDS || open_fds[fd] == -1 ) {
    1.51 +	    sh4r.r[0] = -1;
    1.52 +	} else {
    1.53  	    char *buf = mem_get_region( sh4r.r[6] );
    1.54  	    int length = sh4r.r[7];
    1.55 -	    sh4r.r[0] = read( 0, buf, length );
    1.56 +	    sh4r.r[0] = read( open_fds[fd], buf, length );
    1.57 +	}
    1.58 +	break;
    1.59 +    case SYS_WRITE:
    1.60 +	fd = sh4r.r[5];
    1.61 +	if( fd < 0 || fd >= MAX_OPEN_FDS || open_fds[fd] == -1 ) {
    1.62 +	    sh4r.r[0] = -1;
    1.63  	} else {
    1.64 +	    char *buf = mem_get_region( sh4r.r[6] );
    1.65 +	    int length = sh4r.r[7];
    1.66 +	    sh4r.r[0] = write( open_fds[fd], buf, length );
    1.67 +	}
    1.68 +	break;
    1.69 +    case SYS_LSEEK:
    1.70 +	fd = sh4r.r[5];
    1.71 +	if( fd < 0 || fd >= MAX_OPEN_FDS || open_fds[fd] == -1 ) {
    1.72 +	    sh4r.r[0] = -1;
    1.73 +	} else {
    1.74 +	    sh4r.r[0] = lseek( open_fds[fd], sh4r.r[6], sh4r.r[7] );
    1.75 +	}
    1.76 +	break;
    1.77 +
    1.78 +/* Secure access only */
    1.79 +    case SYS_OPEN:
    1.80 +	if( dcload_allow_unsafe ) {
    1.81 +	    fd = dcload_alloc_fd();
    1.82 +	    if( fd == -1 ) {
    1.83 +		sh4r.r[0] = -1;
    1.84 +	    } else {
    1.85 +		char *filename = mem_get_region( sh4r.r[5] );
    1.86 +		int realfd = open( filename, sh4r.r[6] );
    1.87 +		open_fds[fd] = realfd;
    1.88 +		sh4r.r[0] = realfd;
    1.89 +	    }
    1.90 +	} else {
    1.91 +	    ERROR( "Denying access to local filesystem" );
    1.92  	    sh4r.r[0] = -1;
    1.93  	}
    1.94  	break;
    1.95 -    case SYS_WRITE:
    1.96 -	if( sh4r.r[5] == 1 || sh4r.r[5] == 2 ) {
    1.97 -	    char *buf = mem_get_region( sh4r.r[6] );
    1.98 -	    int length = sh4r.r[7];
    1.99 -	    sh4r.r[0] = write( sh4r.r[5], buf, length );
   1.100 -	} else {
   1.101 -	    sh4r.r[0] = -1;
   1.102 +    case SYS_CLOSE:
   1.103 +	if( dcload_allow_unsafe ) {
   1.104 +	    fd = sh4r.r[5];
   1.105 +	    if( fd < 0 || fd >= MAX_OPEN_FDS || open_fds[fd] == -1 ) {
   1.106 +		sh4r.r[0] = -1;
   1.107 +	    } else {
   1.108 +		if( open_fds[fd] > 2 ) {
   1.109 +		    sh4r.r[0] = close( open_fds[fd] );
   1.110 +		} else {
   1.111 +		    /* Don't actually close real fds 0-2 */
   1.112 +		    sh4r.r[0] = 0;
   1.113 +		}
   1.114 +		open_fds[fd] = -1;
   1.115 +	    }
   1.116  	}
   1.117  	break;
   1.118      case SYS_EXIT:
   1.119 -	if( dcload_allow_exit ) 
   1.120 +	if( dcload_allow_unsafe ) {
   1.121  	    exit( sh4r.r[5] );
   1.122 -	else
   1.123 +	} else {
   1.124  	    dreamcast_stop();
   1.125 +	}
   1.126      default:
   1.127  	sh4r.r[0] = -1;
   1.128      }
   1.129 @@ -90,6 +154,10 @@
   1.130  
   1.131  void dcload_install() 
   1.132  {
   1.133 +    memset( &open_fds, -1, sizeof(open_fds) );
   1.134 +    open_fds[0] = 0;
   1.135 +    open_fds[1] = 1;
   1.136 +    open_fds[2] = 2;
   1.137      syscall_add_hook_vector( 0xF0, SYSCALL_ADDR, dcload_syscall );
   1.138      sh4_write_long( SYS_MAGIC_ADDR, SYS_MAGIC );
   1.139  }