1 files changed, 90 insertions, 0 deletions
diff --git a/contrib/pam_modules/pam_passwdqc/passwdqc_random.c b/contrib/pam_modules/pam_passwdqc/passwdqc_random.c
new file mode 100644
index 0000000..cffd9f3
--- /dev/null
+++ b/contrib/pam_modules/pam_passwdqc/passwdqc_random.c
@@ -0,0 +1,90 @@
+/*
+ * Copyright (c) 2000,2001 by Solar Designer. See LICENSE.
+ */
+
+#include <stdio.h>
+#include <string.h>
+#include <unistd.h>
+#include <errno.h>
+#include <fcntl.h>
+
+#include "passwdqc.h"
+
+#define SEPARATORS			"_,.;:-!&"
+
+static int read_loop(int fd, char *buffer, int count)
+{
+	int offset, block;
+
+	offset = 0;
+	while (count > 0) {
+		block = read(fd, &buffer[offset], count);
+
+		if (block < 0) {
+			if (errno == EINTR) continue;
+			return block;
+		}
+		if (!block) return offset;
+
+		offset += block;
+		count -= block;
+	}
+
+	return offset;
+}
+
+char *_passwdqc_random(passwdqc_params_t *params)
+{
+	static char output[0x100];
+	int bits;
+	int use_separators, count, length, index;
+	char *start, *end;
+	int fd;
+	unsigned char bytes[2];
+
+	if (!(bits = params->random_bits))
+		return NULL;
+
+	count = 1 + ((bits - 12) + 14) / 15;
+	use_separators = ((bits + 11) / 12 != count);
+
+	length = count * 7 - 1;
+	if (length >= sizeof(output) || length > params->max) return NULL;
+
+	if ((fd = open("/dev/urandom", O_RDONLY)) < 0) return NULL;
+
+	length = 0;
+	do {
+		if (read_loop(fd, bytes, sizeof(bytes)) != sizeof(bytes)) {
+			close(fd);
+			return NULL;
+		}
+
+		index = (((int)bytes[1] & 0x0f) << 8) | (int)bytes[0];
+		start = _passwdqc_wordset_4k[index];
+		end = memchr(start, '\0', 6);
+		if (!end) end = start + 6;
+		if (length + (end - start) >= sizeof(output) - 1) {
+			close(fd);
+			return NULL;
+		}
+		memcpy(&output[length], start, end - start);
+		length += end - start;
+		bits -= 12;
+
+		if (use_separators && bits > 3) {
+			index = ((int)bytes[1] & 0x70) >> 4;
+			output[length++] = SEPARATORS[index];
+			bits -= 3;
+		} else
+		if (bits > 0)
+			output[length++] = ' ';
+	} while (bits > 0);
+
+	memset(bytes, 0, sizeof(bytes));
+	output[length] = '\0';
+
+	close(fd);
+
+	return output;
+}