/* -*- Mode: C; tab-width: 4; c-basic-offset: 4; indent-tabs-mode: nil -*- */
#include "memcached.h"
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <sasl/saslplug.h>
char my_sasl_hostname[1025];
#if defined(HAVE_SASL_CB_GETCONF) || defined(HAVE_SASL_CB_GETCONFPATH)
/* The locations we may search for a SASL config file if the user didn't
* specify one in the environment variable SASL_CONF_PATH
*/
const char * const locations[] = {
"/etc/sasl/memcached.conf",
"/etc/sasl2/memcached.conf",
NULL
};
#endif
#ifndef HAVE_SASL_CALLBACK_FT
typedef int (*sasl_callback_ft)(void);
#endif
#ifdef ENABLE_SASL_PWDB
#define MAX_ENTRY_LEN 256
static const char *memcached_sasl_pwdb;
static int sasl_server_userdb_checkpass(sasl_conn_t *conn,
void *context,
const char *user,
const char *pass,
unsigned passlen,
struct propctx *propctx)
{
size_t unmlen = strlen(user);
if ((passlen + unmlen) > (MAX_ENTRY_LEN - 4)) {
fprintf(stderr,
"WARNING: Failed to authenticate <%s> due to too long password (%d)\n",
user, passlen);
return SASL_NOAUTHZ;
}
FILE *pwfile = fopen(memcached_sasl_pwdb, "r");
if (pwfile == NULL) {
if (settings.verbose) {
vperror("WARNING: Failed to open sasl database <%s>",
memcached_sasl_pwdb);
}
return SASL_NOAUTHZ;
}
char buffer[MAX_ENTRY_LEN];
bool ok = false;
while ((fgets(buffer, sizeof(buffer), pwfile)) != NULL) {
if (memcmp(user, buffer, unmlen) == 0 && buffer[unmlen] == ':') {
/* This is the correct user */
++unmlen;
if (memcmp(pass, buffer + unmlen, passlen) == 0 &&
(buffer[unmlen + passlen] == ':' || /* Additional tokens */
buffer[unmlen + passlen] == '\n' || /* end of line */
buffer[unmlen + passlen] == '\r'|| /* dos format? */
buffer[unmlen + passlen] == '\0')) { /* line truncated */
ok = true;
}
break;
}
}
(void)fclose(pwfile);
if (ok) {
return SASL_OK;
}
if (settings.verbose) {
fprintf(stderr, "INFO: User <%s> failed to authenticate\n", user);
}
return SASL_NOAUTHZ;
}
#endif
#if defined(HAVE_SASL_CB_GETCONF) || defined(HAVE_SASL_CB_GETCONFPATH)
static int sasl_getconf(void *context, const char **path)
{
*path = getenv("SASL_CONF_PATH");
if (*path == NULL) {
for (int i = 0; locations[i] != NULL; ++i) {
if (access(locations[i], F_OK) == 0) {
*path = locations[i];
break;
}
}
}
if (settings.verbose) {
if (*path != NULL) {
fprintf(stderr, "Reading configuration from: <%s>\n", *path);
} else {
fprintf(stderr, "Failed to locate a config path\n");
}
}
return (*path != NULL) ? SASL_OK : SASL_FAIL;
}
#endif
static int sasl_log(void *context, int level, const char *message)
{
bool log = true;
switch (level) {
case SASL_LOG_NONE:
log = false;
break;
case SASL_LOG_PASS:
case SASL_LOG_TRACE:
case SASL_LOG_DEBUG:
case SASL_LOG_NOTE:
if (settings.verbose < 2) {
log = false;
}
break;
case SASL_LOG_WARN:
case SASL_LOG_FAIL:
if (settings.verbose < 1) {
log = false;
}
break;
default:
/* This is an error */
;
}
if (log) {
fprintf(stderr, "SASL (severity %d): %s\n", level, message);
}
return SASL_OK;
}
static sasl_callback_t sasl_callbacks[] = {
#ifdef ENABLE_SASL_PWDB
{ SASL_CB_SERVER_USERDB_CHECKPASS, (sasl_callback_ft)sasl_server_userdb_checkpass, NULL },
#endif
{ SASL_CB_LOG, (sasl_callback_ft)sasl_log, NULL },
#ifdef HAVE_SASL_CB_GETCONF
{ SASL_CB_GETCONF, sasl_getconf, NULL },
#else
#ifdef HAVE_SASL_CB_GETCONFPATH
{ SASL_CB_GETCONFPATH, (sasl_callback_ft)sasl_getconf, NULL },
#endif
#endif
{ SASL_CB_LIST_END, NULL, NULL }
};
void init_sasl(void) {
#ifdef ENABLE_SASL_PWDB
memcached_sasl_pwdb = getenv("MEMCACHED_SASL_PWDB");
if (memcached_sasl_pwdb == NULL) {
if (settings.verbose) {
fprintf(stderr,
"INFO: MEMCACHED_SASL_PWDB not specified. "
"Internal passwd database disabled\n");
}
sasl_callbacks[0].id = SASL_CB_LIST_END;
sasl_callbacks[0].proc = NULL;
}
#endif
memset(my_sasl_hostname, 0, sizeof(my_sasl_hostname));
if (gethostname(my_sasl_hostname, sizeof(my_sasl_hostname)-1) == -1) {
if (settings.verbose) {
fprintf(stderr, "Error discovering hostname for SASL\n");
}
my_sasl_hostname[0] = '\0';
}
if (sasl_server_init(sasl_callbacks, "memcached") != SASL_OK) {
fprintf(stderr, "Error initializing sasl.\n");
exit(EXIT_FAILURE);
} else {
if (settings.verbose) {
fprintf(stderr, "Initialized SASL.\n");
}
}
}