claws-mail/src/common/smtp.c

679 lines
17 KiB
C

/*
* Sylpheed -- a GTK+ based, lightweight, and fast e-mail client
* Copyright (C) 1999-2012 Hiroyuki Yamamoto and the Claws Mail team
*
* 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 3 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, see <http://www.gnu.org/licenses/>.
*
*/
#ifdef HAVE_CONFIG_H
# include "config.h"
#include "claws-features.h"
#endif
#include <glib.h>
#ifdef ENABLE_NLS
#include <glib/gi18n.h>
#else
#define _(a) (a)
#define N_(a) (a)
#endif
#include <stdio.h>
#include <string.h>
#include "smtp.h"
#include "md5.h"
#include "utils.h"
#include "log.h"
static void smtp_session_destroy(Session *session);
static gint smtp_auth(SMTPSession *session);
#ifdef USE_GNUTLS
static gint smtp_starttls(SMTPSession *session);
#endif
static gint smtp_auth_cram_md5(SMTPSession *session);
static gint smtp_auth_login(SMTPSession *session);
static gint smtp_auth_plain(SMTPSession *session);
static gint smtp_ehlo(SMTPSession *session);
static gint smtp_ehlo_recv(SMTPSession *session, const gchar *msg);
static gint smtp_helo(SMTPSession *session);
static gint smtp_rcpt(SMTPSession *session);
static gint smtp_data(SMTPSession *session);
static gint smtp_send_data(SMTPSession *session);
static gint smtp_make_ready(SMTPSession *session);
static gint smtp_eom(SMTPSession *session);
static gint smtp_session_recv_msg(Session *session, const gchar *msg);
static gint smtp_session_send_data_finished(Session *session, guint len);
Session *smtp_session_new(void *prefs_account)
{
SMTPSession *session;
session = g_new0(SMTPSession, 1);
session_init(SESSION(session), prefs_account, TRUE);
SESSION(session)->type = SESSION_SMTP;
SESSION(session)->recv_msg = smtp_session_recv_msg;
SESSION(session)->recv_data_finished = NULL;
SESSION(session)->send_data_finished = smtp_session_send_data_finished;
SESSION(session)->destroy = smtp_session_destroy;
session->state = SMTP_READY;
#ifdef USE_GNUTLS
session->tls_init_done = FALSE;
#endif
session->hostname = NULL;
session->user = NULL;
session->pass = NULL;
session->from = NULL;
session->to_list = NULL;
session->cur_to = NULL;
session->send_data = NULL;
session->send_data_len = 0;
session->max_message_size = -1;
session->avail_auth_type = 0;
session->forced_auth_type = 0;
session->auth_type = 0;
session->esmtp_flags = 0;
session->error_val = SM_OK;
session->error_msg = NULL;
return SESSION(session);
}
static void smtp_session_destroy(Session *session)
{
SMTPSession *smtp_session = SMTP_SESSION(session);
g_free(smtp_session->hostname);
g_free(smtp_session->user);
g_free(smtp_session->pass);
g_free(smtp_session->from);
g_free(smtp_session->send_data);
g_free(smtp_session->error_msg);
}
gint smtp_from(SMTPSession *session)
{
gchar buf[MESSAGEBUFSIZE];
gchar *mail_size = NULL;
cm_return_val_if_fail(session->from != NULL, SM_ERROR);
session->state = SMTP_FROM;
if (session->is_esmtp && (session->esmtp_flags & ESMTP_SIZE)!=0)
mail_size = g_strdup_printf(" SIZE=%d", session->send_data_len);
else
mail_size = g_strdup("");
if (strchr(session->from, '<'))
g_snprintf(buf, sizeof(buf), "MAIL FROM:%s%s", session->from,
mail_size);
else
g_snprintf(buf, sizeof(buf), "MAIL FROM:<%s>%s", session->from,
mail_size);
g_free(mail_size);
if (session_send_msg(SESSION(session), SESSION_MSG_NORMAL, buf) < 0)
return SM_ERROR;
log_print(LOG_PROTOCOL, "%sSMTP> %s\n", (session->is_esmtp?"E":""), buf);
return SM_OK;
}
static gint smtp_auth(SMTPSession *session)
{
cm_return_val_if_fail(session->user != NULL, SM_ERROR);
session->state = SMTP_AUTH;
if ((session->forced_auth_type == SMTPAUTH_CRAM_MD5
|| session->forced_auth_type == 0)
&&
(session->avail_auth_type & SMTPAUTH_CRAM_MD5) != 0)
smtp_auth_cram_md5(session);
else if ((session->forced_auth_type == SMTPAUTH_LOGIN
|| session->forced_auth_type == 0)
&&
(session->avail_auth_type & SMTPAUTH_LOGIN) != 0)
smtp_auth_login(session);
else if ((session->forced_auth_type == SMTPAUTH_PLAIN
|| session->forced_auth_type == 0)
&&
(session->avail_auth_type & SMTPAUTH_PLAIN) != 0)
smtp_auth_plain(session);
else if (session->forced_auth_type == 0) {
log_warning(LOG_PROTOCOL, _("No SMTP AUTH method available\n"));
return SM_AUTHFAIL;
} else {
log_warning(LOG_PROTOCOL, _("Selected SMTP AUTH method not available\n"));
return SM_AUTHFAIL;
}
return SM_OK;
}
static gint smtp_auth_recv(SMTPSession *session, const gchar *msg)
{
gchar buf[MESSAGEBUFSIZE], *tmp;
switch (session->auth_type) {
case SMTPAUTH_LOGIN:
session->state = SMTP_AUTH_LOGIN_USER;
if (!strncmp(msg, "334 ", 4)) {
tmp = g_base64_encode(session->user, strlen(session->user));
if (session_send_msg(SESSION(session), SESSION_MSG_NORMAL,
tmp) < 0) {
g_free(tmp);
return SM_ERROR;
}
g_free(tmp);
log_print(LOG_PROTOCOL, "ESMTP> [USERID]\n");
} else {
/* Server rejects AUTH */
if (session_send_msg(SESSION(session), SESSION_MSG_NORMAL,
"*") < 0)
return SM_ERROR;
log_print(LOG_PROTOCOL, "ESMTP> *\n");
}
break;
case SMTPAUTH_CRAM_MD5:
session->state = SMTP_AUTH_CRAM_MD5;
if (!strncmp(msg, "334 ", 4)) {
gchar *response;
gchar *response64;
gchar *challenge;
gsize challengelen;
guchar hexdigest[33];
challenge = g_base64_decode_zero(msg + 4, &challengelen);
log_print(LOG_PROTOCOL, "ESMTP< [Decoded: %s]\n", challenge);
g_snprintf(buf, sizeof(buf), "%s", session->pass);
md5_hex_hmac(hexdigest, challenge, challengelen,
buf, strlen(session->pass));
g_free(challenge);
response = g_strdup_printf
("%s %s", session->user, hexdigest);
log_print(LOG_PROTOCOL, "ESMTP> [Encoded: %s]\n", response);
response64 = g_base64_encode(response, strlen(response));
g_free(response);
if (session_send_msg(SESSION(session), SESSION_MSG_NORMAL,
response64) < 0) {
g_free(response64);
return SM_ERROR;
}
log_print(LOG_PROTOCOL, "ESMTP> %s\n", response64);
g_free(response64);
} else {
/* Server rejects AUTH */
if (session_send_msg(SESSION(session), SESSION_MSG_NORMAL,
"*") < 0)
return SM_ERROR;
log_print(LOG_PROTOCOL, "ESMTP> *\n");
}
break;
case SMTPAUTH_DIGEST_MD5:
default:
/* stop smtp_auth when no correct authtype */
if (session_send_msg(SESSION(session), SESSION_MSG_NORMAL, "*") < 0)
return SM_ERROR;
log_print(LOG_PROTOCOL, "ESMTP> *\n");
break;
}
return SM_OK;
}
static gint smtp_auth_login_user_recv(SMTPSession *session, const gchar *msg)
{
gchar *tmp;
session->state = SMTP_AUTH_LOGIN_PASS;
if (!strncmp(msg, "334 ", 4)) {
tmp = g_base64_encode(session->pass, strlen(session->pass));
} else {
/* Server rejects AUTH */
tmp = g_strdup("*");
}
if (session_send_msg(SESSION(session), SESSION_MSG_NORMAL, tmp) < 0) {
g_free(tmp);
return SM_ERROR;
}
g_free(tmp);
log_print(LOG_PROTOCOL, "ESMTP> [PASSWORD]\n");
return SM_OK;
}
static gint smtp_ehlo(SMTPSession *session)
{
gchar buf[MESSAGEBUFSIZE];
session->state = SMTP_EHLO;
session->avail_auth_type = 0;
g_snprintf(buf, sizeof(buf), "EHLO %s",
session->hostname ? session->hostname : get_domain_name());
if (session_send_msg(SESSION(session), SESSION_MSG_NORMAL, buf) < 0)
return SM_ERROR;
log_print(LOG_PROTOCOL, "ESMTP> %s\n", buf);
return SM_OK;
}
static gint smtp_ehlo_recv(SMTPSession *session, const gchar *msg)
{
if (strncmp(msg, "250", 3) == 0) {
const gchar *p = msg;
p += 3;
if (*p == '-' || *p == ' ') p++;
if (g_ascii_strncasecmp(p, "AUTH", 4) == 0) {
p += 5;
if (strcasestr(p, "PLAIN"))
session->avail_auth_type |= SMTPAUTH_PLAIN;
if (strcasestr(p, "LOGIN"))
session->avail_auth_type |= SMTPAUTH_LOGIN;
if (strcasestr(p, "CRAM-MD5"))
session->avail_auth_type |= SMTPAUTH_CRAM_MD5;
if (strcasestr(p, "DIGEST-MD5"))
session->avail_auth_type |= SMTPAUTH_DIGEST_MD5;
}
if (g_ascii_strncasecmp(p, "SIZE", 4) == 0) {
p += 5;
session->max_message_size = atoi(p);
session->esmtp_flags |= ESMTP_SIZE;
}
if (g_ascii_strncasecmp(p, "STARTTLS", 8) == 0) {
p += 9;
session->avail_auth_type |= SMTPAUTH_TLS_AVAILABLE;
}
return SM_OK;
} else if ((msg[0] == '1' || msg[0] == '2' || msg[0] == '3') &&
(msg[3] == ' ' || msg[3] == '\0'))
return SM_OK;
else if (msg[0] == '5' && msg[1] == '0' &&
(msg[2] == '4' || msg[2] == '3' || msg[2] == '1'))
return SM_ERROR;
return SM_ERROR;
}
#ifdef USE_GNUTLS
static gint smtp_starttls(SMTPSession *session)
{
session->state = SMTP_STARTTLS;
if (session_send_msg(SESSION(session), SESSION_MSG_NORMAL, "STARTTLS") < 0)
return SM_ERROR;
log_print(LOG_PROTOCOL, "ESMTP> STARTTLS\n");
return SM_OK;
}
#endif
static gint smtp_auth_cram_md5(SMTPSession *session)
{
session->state = SMTP_AUTH;
session->auth_type = SMTPAUTH_CRAM_MD5;
if (session_send_msg(SESSION(session), SESSION_MSG_NORMAL, "AUTH CRAM-MD5") < 0)
return SM_ERROR;
log_print(LOG_PROTOCOL, "ESMTP> AUTH CRAM-MD5\n");
return SM_OK;
}
static gint smtp_auth_plain(SMTPSession *session)
{
gchar buf[MESSAGEBUFSIZE], *b64buf, *out;
gint len;
session->state = SMTP_AUTH_PLAIN;
session->auth_type = SMTPAUTH_PLAIN;
memset(buf, 0, sizeof buf);
/* "\0user\0password" */
len = sprintf(buf, "%c%s%c%s", '\0', session->user, '\0', session->pass);
b64buf = g_base64_encode(buf, len);
out = g_strconcat("AUTH PLAIN ", b64buf, NULL);
g_free(b64buf);
if (session_send_msg(SESSION(session), SESSION_MSG_NORMAL, out) < 0) {
g_free(out);
return SM_ERROR;
}
g_free(out);
log_print(LOG_PROTOCOL, "ESMTP> [AUTH PLAIN]\n");
return SM_OK;
}
static gint smtp_auth_login(SMTPSession *session)
{
session->state = SMTP_AUTH;
session->auth_type = SMTPAUTH_LOGIN;
if (session_send_msg(SESSION(session), SESSION_MSG_NORMAL, "AUTH LOGIN") < 0)
return SM_ERROR;
log_print(LOG_PROTOCOL, "ESMTP> AUTH LOGIN\n");
return SM_OK;
}
static gint smtp_helo(SMTPSession *session)
{
gchar buf[MESSAGEBUFSIZE];
session->state = SMTP_HELO;
g_snprintf(buf, sizeof(buf), "HELO %s",
session->hostname ? session->hostname : get_domain_name());
if (session_send_msg(SESSION(session), SESSION_MSG_NORMAL, buf) < 0)
return SM_ERROR;
log_print(LOG_PROTOCOL, "SMTP> %s\n", buf);
return SM_OK;
}
static gint smtp_rcpt(SMTPSession *session)
{
gchar buf[MESSAGEBUFSIZE];
gchar *to;
cm_return_val_if_fail(session->cur_to != NULL, SM_ERROR);
session->state = SMTP_RCPT;
to = (gchar *)session->cur_to->data;
if (strchr(to, '<'))
g_snprintf(buf, sizeof(buf), "RCPT TO:%s", to);
else
g_snprintf(buf, sizeof(buf), "RCPT TO:<%s>", to);
if (session_send_msg(SESSION(session), SESSION_MSG_NORMAL, buf) < 0)
return SM_ERROR;
log_print(LOG_PROTOCOL, "SMTP> %s\n", buf);
session->cur_to = session->cur_to->next;
return SM_OK;
}
static gint smtp_data(SMTPSession *session)
{
session->state = SMTP_DATA;
if (session_send_msg(SESSION(session), SESSION_MSG_NORMAL, "DATA") < 0)
return SM_ERROR;
log_print(LOG_PROTOCOL, "SMTP> DATA\n");
return SM_OK;
}
static gint smtp_send_data(SMTPSession *session)
{
session->state = SMTP_SEND_DATA;
session_send_data(SESSION(session), session->send_data,
session->send_data_len);
return SM_OK;
}
static gint smtp_make_ready(SMTPSession *session)
{
session->state = SMTP_MAIL_SENT_OK;
return SM_OK;
}
gint smtp_quit(SMTPSession *session)
{
session->state = SMTP_QUIT;
session_send_msg(SESSION(session), SESSION_MSG_NORMAL, "QUIT");
log_print(LOG_PROTOCOL, "SMTP> QUIT\n");
return SM_OK;
}
static gint smtp_eom(SMTPSession *session)
{
session->state = SMTP_EOM;
if (session_send_msg(SESSION(session), SESSION_MSG_NORMAL, ".") < 0)
return SM_ERROR;
log_print(LOG_PROTOCOL, "SMTP> . (EOM)\n");
return SM_OK;
}
static gint smtp_session_recv_msg(Session *session, const gchar *msg)
{
SMTPSession *smtp_session = SMTP_SESSION(session);
gboolean cont = FALSE;
gint ret = 0;
if (strlen(msg) < 4) {
log_warning(LOG_PROTOCOL, _("bad SMTP response\n"));
return -1;
}
switch (smtp_session->state) {
case SMTP_EHLO:
case SMTP_STARTTLS:
case SMTP_AUTH:
case SMTP_AUTH_PLAIN:
case SMTP_AUTH_LOGIN_USER:
case SMTP_AUTH_LOGIN_PASS:
case SMTP_AUTH_CRAM_MD5:
log_print(LOG_PROTOCOL, "ESMTP< %s\n", msg);
break;
default:
log_print(LOG_PROTOCOL, "SMTP< %s\n", msg);
break;
}
/* ignore all multiline responses except for EHLO */
if (msg[3] == '-' && smtp_session->state != SMTP_EHLO)
return session_recv_msg(session);
if (msg[0] == '5' && msg[1] == '0' &&
(msg[2] == '4' || msg[2] == '3' || msg[2] == '1')) {
log_warning(LOG_PROTOCOL, _("error occurred on SMTP session\n"));
smtp_session->state = SMTP_ERROR;
smtp_session->error_val = SM_ERROR;
g_free(smtp_session->error_msg);
smtp_session->error_msg = g_strdup(msg);
return -1;
}
if (!strncmp(msg, "535", 3)) {
log_warning(LOG_PROTOCOL, _("error occurred on authentication\n"));
smtp_session->state = SMTP_ERROR;
smtp_session->error_val = SM_AUTHFAIL;
g_free(smtp_session->error_msg);
smtp_session->error_msg = g_strdup(msg);
return -1;
}
if (msg[0] != '1' && msg[0] != '2' && msg[0] != '3') {
log_warning(LOG_PROTOCOL, _("error occurred on SMTP session\n"));
smtp_session->state = SMTP_ERROR;
smtp_session->error_val = SM_ERROR;
g_free(smtp_session->error_msg);
smtp_session->error_msg = g_strdup(msg);
return -1;
}
if (msg[3] == '-')
cont = TRUE;
else if (msg[3] != ' ' && msg[3] != '\0') {
log_warning(LOG_PROTOCOL, _("bad SMTP response\n"));
smtp_session->state = SMTP_ERROR;
smtp_session->error_val = SM_UNRECOVERABLE;
return -1;
}
switch (smtp_session->state) {
case SMTP_READY:
if (strstr(msg, "ESMTP"))
smtp_session->is_esmtp = TRUE;
#ifdef USE_GNUTLS
if (smtp_session->user || session->ssl_type != SSL_NONE ||
smtp_session->is_esmtp)
#else
if (smtp_session->user || smtp_session->is_esmtp)
#endif
ret = smtp_ehlo(smtp_session);
else
ret = smtp_helo(smtp_session);
break;
case SMTP_HELO:
ret = smtp_from(smtp_session);
break;
case SMTP_EHLO:
ret = smtp_ehlo_recv(smtp_session, msg);
if (cont == TRUE)
break;
if (smtp_session->max_message_size > 0
&& smtp_session->max_message_size <
smtp_session->send_data_len) {
log_warning(LOG_PROTOCOL, _("Message is too big "
"(Maximum size is %s)\n"),
to_human_readable(
(goffset)(smtp_session->max_message_size)));
smtp_session->state = SMTP_ERROR;
smtp_session->error_val = SM_ERROR;
return -1;
}
#ifdef USE_GNUTLS
if (session->ssl_type == SSL_STARTTLS &&
smtp_session->tls_init_done == FALSE) {
ret = smtp_starttls(smtp_session);
break;
}
#endif
if (smtp_session->user) {
if (smtp_auth(smtp_session) != SM_OK) {
#ifdef USE_GNUTLS
if (session->ssl_type == SSL_NONE
&& smtp_session->tls_init_done == FALSE
&& (smtp_session->avail_auth_type & SMTPAUTH_TLS_AVAILABLE))
ret = smtp_starttls(smtp_session);
else
#endif
ret = smtp_from(smtp_session);
}
} else
ret = smtp_from(smtp_session);
break;
case SMTP_STARTTLS:
#ifdef USE_GNUTLS
if (session_start_tls(session) < 0) {
log_warning(LOG_PROTOCOL, _("couldn't start TLS session\n"));
smtp_session->state = SMTP_ERROR;
smtp_session->error_val = SM_ERROR;
return -1;
}
smtp_session->tls_init_done = TRUE;
ret = smtp_ehlo(smtp_session);
#endif
break;
case SMTP_AUTH:
ret = smtp_auth_recv(smtp_session, msg);
break;
case SMTP_AUTH_LOGIN_USER:
ret = smtp_auth_login_user_recv(smtp_session, msg);
break;
case SMTP_AUTH_PLAIN:
case SMTP_AUTH_LOGIN_PASS:
case SMTP_AUTH_CRAM_MD5:
ret = smtp_from(smtp_session);
break;
case SMTP_FROM:
if (smtp_session->cur_to)
ret = smtp_rcpt(smtp_session);
break;
case SMTP_RCPT:
if (smtp_session->cur_to)
ret = smtp_rcpt(smtp_session);
else
ret = smtp_data(smtp_session);
break;
case SMTP_DATA:
ret = smtp_send_data(smtp_session);
break;
case SMTP_EOM:
smtp_make_ready(smtp_session);
break;
case SMTP_QUIT:
session_disconnect(session);
break;
case SMTP_ERROR:
default:
log_warning(LOG_PROTOCOL, _("error occurred on SMTP session\n"));
smtp_session->error_val = SM_ERROR;
return -1;
}
if (cont && ret == SM_OK)
return session_recv_msg(session);
if (ret != SM_OK)
smtp_session->error_val = SM_ERROR;
return ret == SM_OK ? 0 : -1;
}
static gint smtp_session_send_data_finished(Session *session, guint len)
{
return smtp_eom(SMTP_SESSION(session));
}