From bae8f986336383f688f0cf913e6315d430217095 Mon Sep 17 00:00:00 2001 From: Denys Vlasenko Date: Sun, 3 Jan 2016 22:43:40 +0100 Subject: [PATCH] login: add commented-out PAM double password avoidance from BZ 4003 Signed-off-by: Denys Vlasenko --- loginutils/login.c | 43 +++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 43 insertions(+) diff --git a/loginutils/login.c b/loginutils/login.c index 67fe82e86..4ebc18502 100644 --- a/loginutils/login.c +++ b/loginutils/login.c @@ -78,6 +78,49 @@ * Apparently they like to confuse people. */ # include # include + +# if 0 +/* This supposedly can be used to avoid double password prompt, + * if used instead of standard misc_conv(): + * + * "When we want to authenticate first with local method and then with tacacs for example, + * the password is asked for local method and if not good is asked a second time for tacacs. + * So if we want to authenticate a user with tacacs, and the user exists localy, the password is + * asked two times before authentication is accepted." + * + * However, code looks shaky. For example, why misc_conv() return value is ignored? + * Are msg[i] and resp[i] indexes handled correctly? + */ +static char *passwd = NULL; +static int my_conv(int num_msg, const struct pam_message **msg, + struct pam_response **resp, void *data) +{ + int i; + for (i = 0; i < num_msg; i++) { + switch (msg[i]->msg_style) { + case PAM_PROMPT_ECHO_OFF: + if (passwd == NULL) { + misc_conv(num_msg, msg, resp, data); + passwd = xstrdup(resp[i]->resp); + return PAM_SUCCESS; + } + + resp[0] = xzalloc(sizeof(struct pam_response)); + resp[0]->resp = passwd; + passwd = NULL; + resp[0]->resp_retcode = PAM_SUCCESS; + resp[1] = NULL; + return PAM_SUCCESS; + + default: + break; + } + } + + return PAM_SUCCESS; +} +# endif + static const struct pam_conv conv = { misc_conv, NULL -- 2.25.1