char *
path_normalize( char *path )
{
pem_t *pemp = pem_alloc( path );
pa_t *pap = pa_alloc( );
char *pep;
char *npath;
ASSERT( path[ 0 ] == '/' );
while ( ( pep = pem_next( pemp )) != 0 ) {
if ( ! strcmp( pep, "" )) {
free( ( void * )pep );
continue;
}
if ( ! strcmp( pep, "." )) {
free( ( void * )pep );
continue;
}
if ( ! strcmp( pep, ".." )) {
int ok;
free( ( void * )pep );
ok = pa_peel( pap );
if ( ! ok ) {
pa_free( pap );
pem_free( pemp );
return 0;
}
continue;
}
pa_append( pap, pep );
}
npath = pa_gen( pap );
pa_free( pap );
pem_free( pemp );
return npath;
}
/**
* Locate boundary marker line
*
* @v image PEM image
* @v offset Starting offset
* @v marker Boundary marker
* @ret offset Offset to boundary marker line, or negative error
*/
static int pem_marker ( struct image *image, size_t offset,
const char *marker ) {
char buf[ strlen ( marker ) ];
/* Sanity check */
assert ( offset <= image->len );
/* Scan for marker at start of line */
while ( offset < image->len ) {
/* Check for marker */
if ( ( image->len - offset ) < sizeof ( buf ) )
break;
copy_from_user ( buf, image->data, offset, sizeof ( buf ) );
if ( memcmp ( buf, marker, sizeof ( buf ) ) == 0 )
return offset;
/* Move to next line */
offset = pem_next ( image, offset );
assert ( offset <= image->len );
}
return -ENOENT;
}
/**
* Extract ASN.1 object from image
*
* @v image PEM image
* @v offset Offset within image
* @v cursor ASN.1 cursor to fill in
* @ret next Offset to next image, or negative error
*
* The caller is responsible for eventually calling free() on the
* allocated ASN.1 cursor.
*/
static int pem_asn1 ( struct image *image, size_t offset,
struct asn1_cursor **cursor ) {
size_t encoded_len;
size_t decoded_max_len;
char *encoded;
void *decoded;
int begin;
int end;
int len;
int rc;
/* Locate and skip BEGIN marker */
begin = pem_marker ( image, offset, PEM_BEGIN );
if ( begin < 0 ) {
rc = begin;
DBGC ( image, "PEM %s [%#zx,%#zx) missing BEGIN marker: %s\n",
image->name, offset, image->len, strerror ( rc ) );
goto err_begin;
}
begin = pem_next ( image, begin );
/* Locate and skip END marker */
end = pem_marker ( image, begin, PEM_END );
if ( end < 0 ) {
rc = end;
DBGC ( image, "PEM %s [%#zx,%#zx) missing END marker: %s\n",
image->name, offset, image->len, strerror ( rc ) );
goto err_end;
}
encoded_len = ( end - begin );
end = pem_next ( image, end );
/* Extract Base64-encoded data */
encoded = malloc ( encoded_len + 1 /* NUL */ );
if ( ! encoded ) {
rc = -ENOMEM;
goto err_alloc_encoded;
}
copy_from_user ( encoded, image->data, begin, encoded_len );
encoded[encoded_len] = '\0';
/* Allocate cursor and data buffer */
decoded_max_len = base64_decoded_max_len ( encoded );
*cursor = malloc ( sizeof ( **cursor ) + decoded_max_len );
if ( ! *cursor ) {
rc = -ENOMEM;
goto err_alloc_cursor;
}
decoded = ( ( ( void * ) *cursor ) + sizeof ( **cursor ) );
/* Decode Base64-encoded data */
len = base64_decode ( encoded, decoded, decoded_max_len );
if ( len < 0 ) {
rc = len;
DBGC ( image, "PEM %s could not decode: %s\n",
image->name, strerror ( rc ) );
goto err_decode;
}
(*cursor)->data = decoded;
(*cursor)->len = len;
assert ( (*cursor)->len <= decoded_max_len );
/* Free Base64-encoded data */
free ( encoded );
/* Update offset and skip any unencapsulated trailer */
offset = end;
if ( pem_marker ( image, offset, PEM_BEGIN ) < 0 )
offset = image->len;
return offset;
err_decode:
free ( *cursor );
*cursor = NULL;
err_alloc_cursor:
free ( encoded );
err_alloc_encoded:
err_end:
err_begin:
return rc;
}
