/* * Copyright (C) 2000-2006,2012 Brendan Cully * * This program is free software; you can redistribute it and/or modify * it under the terms of the GNU General Public License as published by * the Free Software Foundation; either version 2 of the License, or * (at your option) any later version. * * This program is distributed in the hope that it will be useful, * but WITHOUT ANY WARRANTY; without even the implied warranty of * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the * GNU General Public License for more details. * * You should have received a copy of the GNU General Public License * along with this program; if not, write to the Free Software * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA. */ /* SASL login/authentication code */ #if HAVE_CONFIG_H # include "config.h" #endif #include "mutt.h" #include "mutt_sasl.h" #include "imap_private.h" #include "auth.h" #include #include /* imap_auth_sasl: Default authenticator if available. */ imap_auth_res_t imap_auth_sasl (IMAP_DATA* idata, const char* method) { sasl_conn_t* saslconn; sasl_interact_t* interaction = NULL; int rc, irc; char *buf = NULL; size_t bufsize = 0; const char* mech; const char *pc = NULL; unsigned int len, olen; unsigned char client_start; if (mutt_sasl_client_new (idata->conn, &saslconn) < 0) { dprint (1, (debugfile, "imap_auth_sasl: Error allocating SASL connection.\n")); return IMAP_AUTH_FAILURE; } rc = SASL_FAIL; /* If the user hasn't specified a method, use any available */ if (!method) { method = idata->capstr; /* hack for SASL ANONYMOUS support: * 1. Fetch username. If it's "" or "anonymous" then * 2. attempt sasl_client_start with only "AUTH=ANONYMOUS" capability * 3. if sasl_client_start fails, fall through... */ if (mutt_account_getuser (&idata->conn->account)) { sasl_dispose (&saslconn); return IMAP_AUTH_FAILURE; } if (mutt_bit_isset (idata->capabilities, AUTH_ANON) && (!idata->conn->account.user[0] || !ascii_strncmp (idata->conn->account.user, "anonymous", 9))) rc = sasl_client_start (saslconn, "AUTH=ANONYMOUS", NULL, &pc, &olen, &mech); } else if (!ascii_strcasecmp ("login", method) && !strstr (NONULL (idata->capstr), "AUTH=LOGIN")) { /* do not use SASL login for regular IMAP login (#3556) */ sasl_dispose (&saslconn); return IMAP_AUTH_UNAVAIL; } if (rc != SASL_OK && rc != SASL_CONTINUE) do { rc = sasl_client_start (saslconn, method, &interaction, &pc, &olen, &mech); if (rc == SASL_INTERACT) mutt_sasl_interact (interaction); } while (rc == SASL_INTERACT); client_start = (olen > 0); if (rc != SASL_OK && rc != SASL_CONTINUE) { if (method) dprint (2, (debugfile, "imap_auth_sasl: %s unavailable\n", method)); else dprint (1, (debugfile, "imap_auth_sasl: Failure starting authentication exchange. No shared mechanisms?\n")); /* SASL doesn't support LOGIN, so fall back */ sasl_dispose (&saslconn); return IMAP_AUTH_UNAVAIL; } mutt_message (_("Authenticating (%s)..."), mech); bufsize = ((olen * 2) > LONG_STRING) ? (olen * 2) : LONG_STRING; buf = safe_malloc (bufsize); snprintf (buf, bufsize, "AUTHENTICATE %s", mech); if (mutt_bit_isset (idata->capabilities, SASL_IR) && client_start) { len = mutt_strlen (buf); buf[len++] = ' '; if (sasl_encode64 (pc, olen, buf + len, bufsize - len, &olen) != SASL_OK) { dprint (1, (debugfile, "imap_auth_sasl: error base64-encoding client response.\n")); goto bail; } client_start = olen = 0; } imap_cmd_start (idata, buf); irc = IMAP_CMD_CONTINUE; /* looping protocol */ while (rc == SASL_CONTINUE || olen > 0) { do irc = imap_cmd_step (idata); while (irc == IMAP_CMD_CONTINUE); if (irc == IMAP_CMD_BAD || irc == IMAP_CMD_NO) goto bail; if (irc == IMAP_CMD_RESPOND) { /* Exchange incorrectly returns +\r\n instead of + \r\n */ if (idata->buf[1] == '\0') { buf[0] = '\0'; len = 0; } else { len = strlen (idata->buf + 2); if (len > bufsize) { bufsize = len; safe_realloc (&buf, bufsize); } /* For sasl_decode64, the fourth parameter, outmax, doesn't * include space for the trailing null */ if (sasl_decode64 (idata->buf+2, len, buf, bufsize - 1, &len) != SASL_OK) { dprint (1, (debugfile, "imap_auth_sasl: error base64-decoding server response.\n")); goto bail; } } } /* client-start is only available with the SASL-IR extension, but * SASL 2.1 seems to want to use it regardless, at least for DIGEST * fast reauth. Override if the server sent an initial continuation */ if (!client_start || buf[0]) { do { rc = sasl_client_step (saslconn, buf, len, &interaction, &pc, &olen); if (rc == SASL_INTERACT) mutt_sasl_interact (interaction); } while (rc == SASL_INTERACT); } else client_start = 0; /* send out response, or line break if none needed */ if (olen) { if ((olen * 2) > bufsize) { bufsize = olen * 2; safe_realloc (&buf, bufsize); } if (sasl_encode64 (pc, olen, buf, bufsize, &olen) != SASL_OK) { dprint (1, (debugfile, "imap_auth_sasl: error base64-encoding client response.\n")); goto bail; } } if (irc == IMAP_CMD_RESPOND) { strfcpy (buf + olen, "\r\n", bufsize - olen); mutt_socket_write (idata->conn, buf); } /* If SASL has errored out, send an abort string to the server */ if (rc < 0) { mutt_socket_write (idata->conn, "*\r\n"); dprint (1, (debugfile, "imap_auth_sasl: sasl_client_step error %d\n",rc)); } olen = 0; } while (irc != IMAP_CMD_OK) if ((irc = imap_cmd_step (idata)) != IMAP_CMD_CONTINUE) break; if (rc != SASL_OK) goto bail; if (imap_code (idata->buf)) { mutt_sasl_setup_conn (idata->conn, saslconn); FREE (&buf); return IMAP_AUTH_SUCCESS; } bail: sasl_dispose (&saslconn); FREE (&buf); if (method) { dprint (2, (debugfile, "imap_auth_sasl: %s failed\n", method)); return IMAP_AUTH_UNAVAIL; } mutt_error _("SASL authentication failed."); mutt_sleep(2); return IMAP_AUTH_FAILURE; }