1 files changed, 75 insertions, 0 deletions
diff --git a/sha1num.c b/sha1num.c
new file mode 100644
index 0000000..41e8f1e
--- /dev/null
+++ b/sha1num.c
@@ -0,0 +1,75 @@
+/*
+ * sha1num.c --- generate sha1 hash based, pseudo random numbers
+ *
+ * Copyright (C) 2005 by Olivier Guerrier
+ *
+ * This file may be distributed under the terms of the GNU Public
+ * License.
+ */
+
+#include <string.h>
+#include <stdio.h>
+#include <stdlib.h>
+#include "pwgen.h"
+#include "sha1.h"
+
+sha1_context sha1_ctx;
+char *sha1_seed;
+const char *sha1_magic="pwgen";
+unsigned char sha1sum[20];
+int sha1sum_idx=20;
+	
+void pw_sha1_init(char *sha1)
+{
+        int i = 0;
+	char *seed;
+	FILE *f;
+        unsigned char buf[1024];
+
+	if ((seed = strchr(sha1,'#'))) {
+		*(seed++) = 0;
+		sha1_seed = malloc(strlen(seed)+1);
+	        if (!sha1_seed) {
+	                fprintf(stderr, "Couldn't malloc sha1_seed buffer.\n");
+	                exit(1);
+	        }
+		strcpy(sha1_seed, seed);
+	}
+	else {
+		sha1_seed = malloc(strlen(sha1_magic)+1);
+	        if (!sha1_seed) {
+	                fprintf(stderr, "Couldn't malloc sha1_seed buffer.\n");
+	                exit(1);
+	        }
+		strcpy(sha1_seed, sha1_magic);
+	}
+
+	if( ! ( f = fopen( sha1, "rb" ) ) ) {
+	        fprintf(stderr, "Couldn't open file: %s.\n", sha1);
+		exit(1);
+	}
+
+	sha1_starts( &sha1_ctx );                                   
+	while( ( i = fread( buf, 1, sizeof( buf ), f ) ) > 0 ) {
+		sha1_update( &sha1_ctx, buf, i );
+	}
+
+	return;
+}
+
+
+int pw_sha1_number(int max_num)
+{
+	int val;
+	sha1_context ctx;
+	
+	if (sha1sum_idx>19) {
+		sha1sum_idx = 0;
+		sha1_update(&sha1_ctx, (unsigned char *) sha1_seed, 
+			    strlen(sha1_seed));
+		ctx = sha1_ctx;
+		sha1_finish(&ctx, sha1sum );
+	}
+	val = (int) (sha1sum[sha1sum_idx++] / ((float) 256) * max_num);
+	return (val);
+}