mkpasswd: use urandom for salts, cleanup

Using /dev/random for salt generation is pointless -- it can block, and
any extra randomness it would provide (which is debatable) is not needed,
as salts only need to be unique, not unpredictable.

diff --git a/extensions/m_mkpasswd.c b/extensions/m_mkpasswd.c
index 66d06413dda1e7d9f075ba4587b54cfcb1467088..66d7d6b080774f4996c538e909623e5aed476561 100644 (file)
--- a/extensions/m_mkpasswd.c
+++ b/extensions/m_mkpasswd.c
@@ -189,36 +189,31 @@ char *
 generate_poor_salt(char *salt, int length)
 {
        int i;
+
        srand(time(NULL));
        for(i = 0; i < length; i++)
-       {
                salt[i] = saltChars[rand() % 64];
-       }
+
        return (salt);
 }
 
 char *
 generate_random_salt(char *salt, int length)
 {
-       char *buf;
        int fd, i;
-       if((fd = open("/dev/random", O_RDONLY)) < 0)
-       {
+
+       if((fd = open("/dev/urandom", O_RDONLY)) < 0)
                return (generate_poor_salt(salt, length));
-       }
-       buf = calloc(1, length);
-       if(read(fd, buf, length) != length)
+
+       if(read(fd, salt, (size_t)length) != length)
        {
-               free(buf);
                close(fd);
                return (generate_poor_salt(salt, length));
        }
 
        for(i = 0; i < length; i++)
-       {
-               salt[i] = saltChars[abs(buf[i]) % 64];
-       }
-       free(buf);
+               salt[i] = saltChars[abs(salt[i]) % 64];
+
        close(fd);
        return (salt);
 }