seitan: try to improve print of the arguments to check

1 files changed, 53 insertions, 5 deletions

diff --git a/operations.c b/operations.c
index cfb3a9c..33596aa 100644
--- a/operations.c
+++ b/operations.c
@@ -546,10 +546,59 @@ int op_bitwise(const struct seccomp_notif *req, int notifier, struct gluten *g,
 	return 0;
 }
 
+static void str_offset_value(const struct seccomp_notif *req, struct gluten *g,
+		const struct gluten_offset *offset, size_t size,
+		char *v, size_t s_str)
+{
+	const void *px = gluten_ptr(&req->data, g, *offset);
+	char t[PATH_MAX];
+
+	if(!px) {
+		err("  empty gluten to read");
+		return;
+	}
+
+	switch(offset->type) {
+	case OFFSET_NULL:
+		snprintf(v, s_str, "offset %d is NULL", offset->offset);
+		return;
+	case OFFSET_SECCOMP_DATA:
+		snprintf(t, PATH_MAX, "%llx", *(long long unsigned *)px);
+		goto print;
+	case OFFSET_INSTRUCTION:
+		snprintf(v, s_str, "offset %d to instruction", offset->offset);
+		return;
+	case OFFSET_METADATA:
+		snprintf(t, PATH_MAX, "%s", metadata_type_str[*(unsigned int *)px]);
+		goto print;
+	default:
+		break;
+	}
+	switch(size) {
+	case sizeof(unsigned int):
+		snprintf(t, PATH_MAX,"%x", *(unsigned int *)px);
+		goto print;
+	case sizeof(long unsigned):
+		snprintf(t, PATH_MAX,"%lx", *(long unsigned*)px);
+		goto print;
+	default:
+		/* For the cases where it isn't possible to have a nice print, just print
+		 * the type and offset
+		 */
+		snprintf(v, s_str, "(type=%s offset=%d) size=%ld", gluten_offset_name[offset->type],
+				 offset->offset, size);
+		return;
+	}
+print:
+	snprintf(v, s_str, "(type=%s offset=%d)='%s'", gluten_offset_name[offset->type],
+				 offset->offset, t);
+}
+
 int op_cmp(const struct seccomp_notif *req, int notifier, struct gluten *g,
 	   struct op_cmp *op)
 {
 	const struct cmp_desc *desc = gluten_ptr(&req->data, g, op->desc);
+	char str_x[PATH_MAX], str_y[PATH_MAX];
 	enum op_cmp_type cmp;
 	const void *px, *py;
 	int res;
@@ -567,10 +616,9 @@ int op_cmp(const struct seccomp_notif *req, int notifier, struct gluten *g,
 	    !check_gluten_limits(desc->x, desc->size) ||
 	    !check_gluten_limits(desc->y, desc->size))
 		return -1;
-
-	debug("  op_cmp: operands x=(%s %d) y=(%s %d) size=%d",
-	      gluten_offset_name[desc->x.type], desc->x.offset,
-	      gluten_offset_name[desc->y.type], desc->y.offset, desc->size);
+	str_offset_value(req, g, &desc->x, desc->size, str_x, PATH_MAX);
+	str_offset_value(req, g, &desc->y, desc->size, str_y, PATH_MAX);
+	debug("  op_cmp: operands x=%s y=%s", str_x, str_y);
 
 	res = memcmp(px, py, desc->size);
 
@@ -624,7 +672,7 @@ int op_nr(const struct seccomp_notif *req, int notifier, struct gluten *g,
 
 	if (gluten_read(NULL, g, &nr, op->nr, sizeof(nr)) == -1)
 		return -1;
-	debug("  op_nr: checking syscall=%ld", nr);
+	debug("  op_nr: checking syscall %s", syscall_name_str[nr]);
 	if (nr == req->data.nr)
 		return 0;