adduser: safe username passing to passwd/addgroup

passwd: support creating SHA passwords
random code shrink

function                                             old     new   delta
crypt_make_pw_salt                                     -      87     +87
adduser_main                                         883     904     +21
...
crypt_make_salt                                       99      89     -10
chpasswd_main                                        329     312     -17
packed_usage                                       28731   28691     -40
passwd_main                                         1070    1000     -70
cryptpw_main                                         310     224     -86
------------------------------------------------------------------------------
(add/remove: 1/0 grow/shrink: 4/12 up/down: 154/-288)        Total: -134 bytes

Signed-off-by: Denys Vlasenko <vda.linux@googlemail.com>

1 files changed, 6 insertions, 5 deletions

diff --git a/loginutils/chpasswd.c b/loginutils/chpasswd.c
index 6c4296faa..f4718c829 100644
--- a/loginutils/chpasswd.c
+++ b/loginutils/chpasswd.c
@@ -37,9 +37,8 @@ int chpasswd_main(int argc UNUSED_PARAM, char **argv)
         char *name, *pass;
         char salt[sizeof("$N$XXXXXXXX")];
         int opt, rc;
-        int rnd = rnd; /* we *want* it to be non-initialized! */
 
-        if (getuid())
+        if (getuid() != 0)
                 bb_error_msg_and_die(bb_msg_perm_denied_are_you_root);
 
         opt_complementary = "m--e:e--m";
@@ -55,10 +54,12 @@ int chpasswd_main(int argc UNUSED_PARAM, char **argv)
                 xuname2uid(name); /* dies if there is no such user */
 
                 if (!(opt & OPT_ENC)) {
-                        rnd = crypt_make_salt(salt, 1, rnd);
+                        crypt_make_salt(salt, 1);
                         if (opt & OPT_MD5) {
-                                strcpy(salt, "$1$");
-                                rnd = crypt_make_salt(salt + 3, 4, rnd);
+                                salt[0] = '$';
+                                salt[1] = '1';
+                                salt[2] = '$';
+                                crypt_make_salt(salt + 3, 4);
                         }
                         pass = pw_encrypt(pass, salt, 0);
                 }