giomba
/
opensc
1
0
Fork 0
Code Issues Pull Requests Projects Releases Wiki Activity

fuzzing: correctly consume fuzzing data

This commit is contained in:
Frank Morgner 2019-10-31 02:34:47 +01:00
parent a3ee8cefc8
commit 3c87ffaa02
1 changed files with 19 additions and 8 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

27
src/tests/fuzzing/fuzz_pkcs15_reader.c
View File

@ -46,6 +46,8 @@ static struct sc_reader_driver fuzz_drv = {
void fuzz_get_chunk(sc_reader_t *reader, const uint8_t **chunk, uint16_t *chunk_size)
{
struct driver_data *data;
uint16_t c_size;
uint8_t *c;
if (chunk)
*chunk = NULL;
@ -57,22 +59,31 @@ void fuzz_get_chunk(sc_reader_t *reader, const uint8_t **chunk, uint16_t *chunk_
return;
}
data = reader->drv_data;
if (!data || !data->Data || data->Size < sizeof *chunk_size) {
if (!data || !data->Data || data->Size < sizeof c_size) {
sc_debug(reader->ctx, SC_LOG_DEBUG_VERBOSE_TOOL, "Invalid Arguments");
return;
}
data->Size -= sizeof *chunk_size;
*chunk_size = (uint16_t) *data->Data;
data->Data += sizeof *chunk_size;
*chunk = data->Data;
/* parse the length of the returned data on two bytes */
c_size = *((uint16_t *) data->Data);
/* consume two bytes from the fuzzing data */
data->Size -= sizeof c_size;
data->Data += sizeof c_size;
if (data->Size < *chunk_size) {
*chunk_size = data->Size;
if (data->Size < c_size) {
c_size = data->Size;
}
/* consume the bytes from the fuzzing data */
c = data->Data;
data->Size -= c_size;
data->Data += c_size;
sc_debug_hex(reader->ctx, SC_LOG_DEBUG_VERBOSE_TOOL,
"Returning fuzzing chunk", *chunk, *chunk_size);
"Returning fuzzing chunk", c, c_size);
*chunk = c;
*chunk_size = c_size;
}
static int fuzz_reader_release(sc_reader_t *reader)