1 files changed, 49 insertions, 0 deletions
diff --git a/misc.cc b/misc.cc
new file mode 100644
index 0000000..0f1be45
--- /dev/null
+++ b/misc.cc
@@ -0,0 +1,49 @@
+#include <sstream>
+#include <string>
+#include "misc.h"
+#include "inttypes.h"
+
+namespace nitrokey {
+namespace misc {
+
+std::string hexdump(const char *p, size_t size) {
+  std::stringstream out;
+  char formatbuf[128];
+  const char *pstart = p;
+
+  for (const char *pend = p + size; p < pend;) {
+    snprintf(formatbuf, 128, "%04x\t", p - pstart);
+    out << formatbuf;
+
+    for (const char *le = p + 16; p < le && p < pend; p++) {
+      snprintf(formatbuf, 128, "%02x ", uint8_t(*p));
+      out << formatbuf;
+    }
+    out << std::endl;
+  }
+  return out.str();
+}
+
+static uint32_t _crc32(uint32_t crc, uint32_t data) {
+  int i;
+  crc = crc ^ data;
+
+  for (i = 0; i < 32; i++) {
+    if (crc & 0x80000000)
+      crc = (crc << 1) ^ 0x04C11DB7;  // polynomial used in STM32
+    else
+      crc = (crc << 1);
+  }
+
+  return crc;
+}
+
+uint32_t stm_crc32(const uint8_t *data, size_t size) {
+  uint32_t crc = 0xffffffff;
+  const uint32_t *pend = (const uint32_t *)(data + size);
+  for (const uint32_t *p = (const uint32_t *)(data); p < pend; p++)
+    crc = _crc32(crc, *p);
+  return crc;
+}
+}
+}