
#ifdef HAVE_CONFIG_H
#include "config.h"
#endif

#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <unistd.h>

#ifdef HAVE_PAM_PAM_APPL_H
# include <pam/pam_appl.h>
#else
# include <security/pam_appl.h>
#endif

#ifdef LINUX_PAM	/* XXX: and OpenPAM? */
# define PAM_MSG_MEMBER(msg, n, member) ((msg)[(n)]->member)
#else
# define PAM_MSG_MEMBER(msg, n, member) ((*(msg))[(n)].member)
#endif

int
my_conv(int n, const struct pam_message **msg,
    struct pam_response **resp, void *data)
{
	struct pam_response *aresp;
	char buf[PAM_MAX_RESP_SIZE];
	const char *p;
	int i;
	
	if (n <= 0 || n > PAM_MAX_NUM_MSG)
		return (PAM_CONV_ERR);
	
	if ((aresp = calloc(n, sizeof *aresp)) == NULL)
		return (PAM_BUF_ERR);
	
	for (i = 0; i < n; ++i) {
		aresp[i].resp_retcode = 0;
		aresp[i].resp = NULL;
		p = PAM_MSG_MEMBER(msg, i, msg);
		
		switch (PAM_MSG_MEMBER(msg, i, msg_style)) {
		case PAM_PROMPT_ECHO_OFF:
			aresp[i].resp = strdup(getpass(p));
			if (aresp[i].resp == NULL)
				goto fail;
			break;
		case PAM_PROMPT_ECHO_ON:
			fputs(p, stderr);
			if (fgets(buf, sizeof(buf), stdin) == NULL)
				goto fail;
			aresp[i].resp = strdup(buf);
			if (aresp[i].resp == NULL)
				goto fail;
			break;
		case PAM_ERROR_MSG:
			fputs(p, stderr);
			if (strlen(p) > 0 && p[strlen(p) - 1] != '\n')
				fputc('\n', stderr);
			break;
		case PAM_TEXT_INFO:
			fputs(p, stdout);
			if (strlen(p) > 0 && p[strlen(p) - 1] != '\n')
				fputc('\n', stdout);
			break;
		default:
			goto fail;
		}
	}
	*resp = aresp;
	return (PAM_SUCCESS);
fail:
	for (i = 0; i < n; ++i) {
		if (aresp[i].resp != NULL)
			free(aresp[i].resp);
	}
	*resp = NULL;
	return (PAM_CONV_ERR);
}

static struct pam_conv conv = { my_conv, NULL };

int
main(int argc, char *argv[])
{
	pam_handle_t *pamh = NULL;
	char *user, *host = NULL;
	int ret;
	
	if (argc < 2) {
		fprintf(stderr, "Usage: testpam <user> [host]\n");
		exit(EXIT_FAILURE);
	}
	user = argv[1];
	if (argc > 2)
		host = argv[2];
	
	if (pam_start("testpam", user, &conv, &pamh) != PAM_SUCCESS) {
		exit(EXIT_FAILURE);
	}
	if (host != NULL) {
		if (pam_set_item(pamh, PAM_RHOST, host) != PAM_SUCCESS)
			exit(EXIT_FAILURE);
	}
	if (pam_authenticate(pamh, 0) != PAM_SUCCESS) {
		exit(EXIT_FAILURE);
	}
	if (pam_end(pamh, ret) != PAM_SUCCESS) {
		exit(EXIT_FAILURE);
	}
	exit(EXIT_SUCCESS);
}