Applied daemon patch, thanks to Rune Magnussen

software/.gitignore

@@ -0,0 +1 @@
+infnoise

software/Makefile

@@ -2,8 +2,8 @@ CFLAGS = -Wall -std=c99 -O3 -I Keccak
 
 all: infnoise
 
-infnoise: infnoise.c infnoise.h healthcheck.c writeentropy.c Keccak/KeccakF-1600-reference.c Keccak/brg_endian.h
-	$(CC) $(CFLAGS) -o infnoise infnoise.c healthcheck.c writeentropy.c Keccak/KeccakF-1600-reference.c -lftdi -lm -lrt
+infnoise: infnoise.c infnoise.h healthcheck.c writeentropy.c daemon.c Keccak/KeccakF-1600-reference.c Keccak/brg_endian.h
+	$(CC) $(CFLAGS) -o infnoise infnoise.c healthcheck.c writeentropy.c daemon.c Keccak/KeccakF-1600-reference.c -lftdi -lm -lrt
 
 clean:
 	$(RM) -f infnoise

software/daemon.c

@@ -0,0 +1,21 @@
+/* Functions used when running in the background
+ */
+
+#include <stdio.h>
+#include <sys/types.h>
+#include <errno.h>
+#include <unistd.h>
+
+#include "infnoise.h"
+
+int writePid(pid_t pid, char *fileName) {
+	FILE *pidFile;
+	int ret;
+	pidFile = fopen(fileName,"w");
+	if(pidFile == NULL)
+		return errno;
+	ret = fprintf(pidFile, "%d\n", pid);
+	if (ret < 0)
+		return ret;
+	return fclose(pidFile);
+}

software/infnoise.c

@@ -9,6 +9,7 @@
 #include <stdlib.h>
 #include <string.h>
 #include <time.h>
+#include <unistd.h>
 #include <ftdi.h>
 #include "infnoise.h"
 #include "KeccakF-1600-interface.h"
@@ -265,6 +266,9 @@ int main(int argc, char **argv)
     uint32_t outputMultiplier = 0; // We output all the entropy when outputMultiplier == 0
     uint32_t xArg;
     bool multiplierAssigned = false;
+    bool pidFile = false;
+    char *pidFileName = NULL;
+    bool runDaemon = false;
 
     // Process arguments
     for(xArg = 1; xArg < argc; xArg++) {
@@ -285,6 +289,12 @@ int main(int argc, char **argv)
                 return 1;
             }
             outputMultiplier = tmpOutputMult;
+	} else if(!strcmp(argv[xArg], "--pidfile")) {
+		xArg++;
+		pidFileName = argv[xArg];
+		pidFile = true;
+	} else if(!strcmp(argv[xArg], "--daemon")) {
+		runDaemon = true;
         } else {
             fputs("Usage: infnoise [options]\n"
                             "Options are:\n"
@@ -293,15 +303,43 @@ int main(int argc, char **argv)
                             "    --raw - do not whiten the output\n"
                             "    --multiplier <value> - write 256 bits * value for each 512 bits written to\n"
                             "      the Keccak sponge.  Default of 0 means write all the entropy.\n"
-                            "    --no-output - do not write random output data\n", stderr);
+                            "    --no-output - do not write random output data\n"
+			    "    --pidfile <file> - write process ID to file\n"
+			    "    --daemon - run in the background\n", stderr);
             return 1;
         }
     }
 
+    if(geteuid() != 0) {
+	fputs("Super user access needed.\n", stderr);
+	return 1;
+    }
+
     if(!multiplierAssigned && writeDevRandom) {
         outputMultiplier = 2; // Don't throw away entropy when writing to /dev/random unless told to do so
     }
 
+    /* If the user wants a pid-file, but no backgrounding then write the current
+       PID. */
+    if (pidFile && !runDaemon) {
+	writePid(getpid(), pidFileName);
+    }
+
+    if (runDaemon) {
+	pid_t pid = fork();
+	if(pid < 0) {
+		fputs("fork() failed\n", stderr);
+		return 1;
+	} else if(pid > 0) {
+		/* Parrent */
+		if(pidFile) {
+			return writePid(pid, pidFileName);
+		}
+		return 0;
+	}
+	/* Pid == 0 - Child  */
+    }
+
     if(writeDevRandom) {
         inmWriteEntropyStart(BUFLEN/8, debug);
     }

software/infnoise.h

@@ -1,5 +1,6 @@
 #include <stdbool.h>
 #include <stdint.h>
+#include <sys/types.h>
 
 // Required accuracy of estimated vs measured entropy in health monitor
 #define INM_ACCURACY 1.03
@@ -17,5 +18,6 @@ void inmWriteEntropyStart(uint32_t bufLen, bool debug);
 void inmWriteEntropyToPool(uint8_t *bytes, uint32_t length, uint32_t entropy);
 void inmWaitForPoolToHaveRoom(void);
 void inmDumpStats(void);
+int writePid(pid_t pid, char *fileName);
 
 extern double inmK, inmExpectedEntropyPerBit;

software/tools/.gitignore

@@ -0,0 +1,7 @@
+bin2hex
+dice
+entcheck
+findlongest
+flipbits
+healthcheck
+hex2bin

software/tools/passgen.c

@@ -0,0 +1,44 @@
+// This is a simple program to read from a binary file of random bits and generate
+// dice rolls.
+
+#include <stdint.h>
+#include <stdio.h>
+#include <stdlib.h>
+#include <math.h>
+
+// Role a single die.
+static uint32_t rollDie(uint32_t sides, FILE *file) {
+  uint32_t randVal;
+  do {
+    uint32_t numBytes = 0;
+    randVal = 0;
+    while (1 << (8*numBytes) <= sides) {
+      numBytes++;
+      int c = getc(file);
+      if (c == EOF) {
+        printf("Ran out of random data\n");
+        exit(1);
+      }
+      randVal = (randVal << 8) | getc(file);
+    }
+  } while(randVal >= sides);
+  return randVal;
+}
+
+int main(int argc, char **argv) {
+  if (argc != 3) {
+    printf("Usage: passgen randFile numKeys\n");
+    return 1;
+  }
+  FILE *file = fopen(argv[1], "r");
+  uint32_t keys = atoi(argv[2]);
+  uint32_t i;
+  printf("password:");
+  for (i = 0; i < keys; i++) {
+    uint32_t randVal = rollDie(26, file);
+    putchar('a' + randVal);
+  }
+  printf("\nThis password has %.2f bits of entropy\n", log(pow(26.0, keys))/log(2));
+  fclose(file);
+  return 0;
+}