#include <postgres.h>
#include <libpq/password.h>
#include <libpq/hba.h>
#include <libpq/libpq.h>
#include <storage/fd.h>
#include <string.h>
#include <unistd.h>
#ifdef HAVE_CRYPT_H
#include <crypt.h>
#endif

int
verify_password(char *user, char *password, Port *port,
				char *database, char *DataDir)
{
	bool		host_ok;
	enum Userauth userauth;
	char		pw_file_name[PWFILE_NAME_SIZE + 1];

	char	   *pw_file_fullname;
	FILE	   *pw_file;

	char		pw_file_line[255];
	char	   *p,
			   *test_user,
			   *test_pw;
	char		salt[3];

	find_hba_entry(DataDir, port->raddr.sin_addr, database,
				   &host_ok, &userauth, pw_file_name, true);

	if (!host_ok)
	{
		sprintf(PQerrormsg,
		   "verify_password: couldn't find entry for connecting host\n");
		fputs(PQerrormsg, stderr);
		pqdebug("%s", PQerrormsg);
		return STATUS_ERROR;
	}

	if (userauth != Password)
	{
		sprintf(PQerrormsg,
				"verify_password: couldn't find entry of type 'password' "
				"for this host\n");
		fputs(PQerrormsg, stderr);
		pqdebug("%s", PQerrormsg);
		return STATUS_ERROR;
	}

	if (!pw_file_name || pw_file_name[0] == '\0')
	{
		sprintf(PQerrormsg,
				"verify_password: no password file specified\n");
		fputs(PQerrormsg, stderr);
		pqdebug("%s", PQerrormsg);
		return STATUS_ERROR;
	}

	pw_file_fullname = (char *) malloc(strlen(DataDir) + strlen(pw_file_name) + 2);
	strcpy(pw_file_fullname, DataDir);
	strcat(pw_file_fullname, "/");
	strcat(pw_file_fullname, pw_file_name);

	pw_file = AllocateFile(pw_file_fullname, "r");
	if (!pw_file)
	{
		sprintf(PQerrormsg,
				"verify_password: couldn't open password file '%s'\n",
				pw_file_fullname);
		fputs(PQerrormsg, stderr);
		pqdebug("%s", PQerrormsg);
		return STATUS_ERROR;
	}

	while (!feof(pw_file))
	{
		fgets(pw_file_line, 255, pw_file);
		p = pw_file_line;

		test_user = strtok(p, ":");
		test_pw = strtok(NULL, ":");
		if (!test_user || !test_pw ||
			test_user[0] == '\0' || test_pw[0] == '\0')
		{
			continue;
		}

		/* kill the newline */
		if (test_pw[strlen(test_pw) - 1] == '\n')
			test_pw[strlen(test_pw) - 1] = '\0';

		strNcpy(salt, test_pw, 2);

		if (strcmp(user, test_user) == 0)
		{
			/* we're outta here one way or the other. */
			FreeFile(pw_file);

			if (strcmp(crypt(password, salt), test_pw) == 0)
			{
				/* it matched. */
				return STATUS_OK;
			}

			sprintf(PQerrormsg,
					"verify_password: password mismatch for '%s'.\n",
					user);
			fputs(PQerrormsg, stderr);
			pqdebug("%s", PQerrormsg);
			return STATUS_ERROR;
		}
	}

	sprintf(PQerrormsg,
			"verify_password: user '%s' not found in password file.\n",
			user);
	fputs(PQerrormsg, stderr);
	pqdebug("%s", PQerrormsg);
	return STATUS_ERROR;
}