first shot for a libinfnoise approach

software/libinfnoise.h

@@ -0,0 +1,111 @@
+#include <stdbool.h>
+#include <stdint.h>
+#include <sys/types.h>
+#include <ftdi.h>
+#include <time.h>
+
+#include <stdint.h>
+#include <stdio.h>
+#include <stdlib.h>
+#include <unistd.h>
+#include <string.h>
+
+
+#define INFNOISE_VENDOR_ID 0x0403
+#define INFNOISE_PRODUCT_ID 0x6015
+
+// Required accuracy of estimated vs measured entropy in health monitor
+#define INM_ACCURACY 1.03
+
+// The FT240X has a 512 byte buffer.  Must be multiple of 64
+// We also write this in one go to the Keccak sponge, which is at most 1600 bits
+#define BUFLEN 512u
+
+// This is how many previous bits are used to predict the next bit from the INM
+#define PREDICTION_BITS 14u
+
+// This is the maximum time we allow to pass to perform the I/O operations, since long
+// delays can reduce entropy from the INM.
+#define MAX_MICROSEC_FOR_SAMPLES 5000u
+
+// This is the gain of each of the two op-amp stages in the INM
+#define DESIGN_K 1.84
+
+#define BITMODE_SYNCBB 0x4
+
+// This defines which pins on the FT240X are used
+#define COMP1 1u
+#define COMP2 4u
+#define SWEN1 2u
+#define SWEN2 0u
+
+// All data bus bits of the FT240X are outputs, except COMP1 and COMP2
+#define MASK (0xffu & ~(1u << COMP1) & ~(1u << COMP2))
+
+// Structure for parsed command line options
+struct opt_struct {
+	uint32_t outputMultiplier; // We output all the entropy when outputMultiplier == 0
+	bool daemon;		// Run as daemon?
+	bool debug;		// Print debugging info?
+	bool devRandom;		// Feed /dev/random?
+	bool noOutput;		// Supress output?
+	bool listDevices;	// List possible USB-devices?
+	bool help;		// Show help
+	bool none;		// set to true when no valid arguments where detected
+	bool raw;		// No whitening?
+	bool version;		// Show version
+	char *pidFileName;	// Name of optional PID-file
+	char *serial;		// Name of selected device
+};
+
+// struct for ftdi_device_descriptor
+struct infnoise_device {
+	uint8_t index;
+	char *manufacturer;
+	char *product;
+	char *serial;
+};
+
+
+struct inm_devlist_node
+{
+    struct infnoise_device *device;
+    struct inm_devlist_node *next;
+};
+
+struct inm_devlist
+{
+    struct inm_devlist_node *head;
+};
+
+// struct for list of devices
+struct infnoise_device_list {
+	struct infnoise_device device;
+	struct infnoise_device_list * next;
+};
+
+bool inmHealthCheckStart(uint8_t N, double K, bool debug);
+void inmHealthCheckStop(void);
+bool inmHealthCheckAddBit(bool evenBit, bool oddBit, bool even);
+bool inmHealthCheckOkToUseData(void);
+double inmHealthCheckEstimateK(void);
+double inmHealthCheckEstimateEntropyPerBit(void);
+uint32_t inmGetEntropyLevel(void);
+void inmClearEntropyLevel(void);
+bool inmEntropyOnTarget(uint32_t entropy, uint32_t bits);
+void inmWriteEntropyStart(uint32_t bufLen, bool debug);
+void inmWriteEntropyToPool(uint8_t *bytes, uint32_t length, uint32_t entropy);
+void inmWaitForPoolToHaveRoom(void);
+void inmDumpStats(void);
+void startDaemon(struct opt_struct *opts);
+bool isSuperUser(void);
+
+extern double inmK, inmExpectedEntropyPerBit;
+struct timespec;
+double diffTime(struct timespec *start, struct timespec *end);
+uint32_t extractBytes(uint8_t *bytes, uint8_t *inBuf);
+void outputBytes(uint8_t *bytes, uint32_t length, uint32_t entropy, bool writeDevRandom);
+bool listUSBDevices(struct ftdi_context *ftdic, struct inm_devlist **result, char** message);
+bool initializeUSB(struct ftdi_context* ftdic, char **message, char *serial);
+uint32_t processBytes(uint8_t *keccakState, uint8_t *bytes, uint8_t *result, uint32_t entropy, bool raw,
+        bool writeDevRandom, uint32_t outputMultiplier, bool noOutput);