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/* Copyright (c) 2002-2018 Dovecot authors, see the included COPYING file */
#include "login-common.h"
#include "base64.h"
#include "buffer.h"
#include "hex-binary.h"
#include "ioloop.h"
#include "istream.h"
#include "ostream.h"
#include "safe-memset.h"
#include "str.h"
#include "str-sanitize.h"
#include "auth-client.h"
#include "../pop3/pop3-capability.h"
#include "client.h"
#include "client-authenticate.h"
#include "pop3-proxy.h"
static const char *capability_string = POP3_CAPABILITY_REPLY;
bool cmd_capa(struct pop3_client *client, const char *args ATTR_UNUSED)
{
const struct auth_mech_desc *mech;
unsigned int i, count;
string_t *str;
str = t_str_new(128);
str_append(str, "+OK\r\n");
str_append(str, capability_string);
if (client_is_tls_enabled(&client->common) && !client->common.tls)
str_append(str, "STLS\r\n");
if (!client->common.set->disable_plaintext_auth ||
client->common.secured)
str_append(str, "USER\r\n");
str_append(str, "SASL");
mech = sasl_server_get_advertised_mechs(&client->common, &count);
for (i = 0; i < count; i++) {
str_append_c(str, ' ');
str_append(str, mech[i].name);
}
str_append(str, "\r\n.\r\n");
client_send_raw(&client->common, str_c(str));
return TRUE;
}
void pop3_client_auth_result(struct client *client,
enum client_auth_result result,
const struct client_auth_reply *reply ATTR_UNUSED,
const char *text)
{
switch (result) {
case CLIENT_AUTH_RESULT_SUCCESS:
/* nothing to be done for POP3 */
break;
case CLIENT_AUTH_RESULT_TEMPFAIL:
client_send_reply(client, POP3_CMD_REPLY_TEMPFAIL, text);
break;
case CLIENT_AUTH_RESULT_AUTHFAILED:
case CLIENT_AUTH_RESULT_AUTHFAILED_REASON:
case CLIENT_AUTH_RESULT_AUTHZFAILED:
case CLIENT_AUTH_RESULT_PASS_EXPIRED:
case CLIENT_AUTH_RESULT_SSL_REQUIRED:
case CLIENT_AUTH_RESULT_LOGIN_DISABLED:
case CLIENT_AUTH_RESULT_MECH_INVALID:
case CLIENT_AUTH_RESULT_MECH_SSL_REQUIRED:
case CLIENT_AUTH_RESULT_INVALID_BASE64:
client_send_reply(client, POP3_CMD_REPLY_AUTH_ERROR, text);
break;
default:
client_send_reply(client, POP3_CMD_REPLY_ERROR, text);
break;
}
}
int cmd_auth(struct pop3_client *pop3_client)
{
/* NOTE: This command's input is handled specially because the
SASL-IR can be large. */
struct client *client = &pop3_client->common;
const unsigned char *data;
size_t i, size;
int ret;
/* <auth mechanism name> [<initial SASL response>] */
if (!pop3_client->auth_mech_name_parsed) {
data = i_stream_get_data(client->input, &size);
for (i = 0; i < size; i++) {
if (data[i] == ' ' ||
data[i] == '\r' || data[i] == '\n')
break;
}
if (i == size)
return 0;
if (i == 0) {
/* Old-style SASL discovery, used by MS Outlook */
unsigned int i, count;
const struct auth_mech_desc *mech;
client_send_raw(client, "+OK\r\n");
mech = sasl_server_get_advertised_mechs(client, &count);
for (i = 0; i < count; i++) {
client_send_raw(client, mech[i].name);
client_send_raw(client, "\r\n");
}
client_send_raw(client, ".\r\n");
(void)i_stream_read_next_line(client->input);
return 1;
}
i_free(client->auth_mech_name);
client->auth_mech_name = i_strndup(data, i);
pop3_client->auth_mech_name_parsed = TRUE;
if (data[i] == ' ')
i++;
i_stream_skip(client->input, i);
}
/* get SASL-IR, if any */
if ((ret = client_auth_read_line(client)) <= 0)
return ret;
const char *ir = NULL;
if (client->auth_response->used > 0)
ir = t_strdup(str_c(client->auth_response));
pop3_client->auth_mech_name_parsed = FALSE;
/* The whole AUTH line command is parsed now. The rest of the SASL
protocol exchange happens in login-common code. We can free the
current command here already, because no pop3-login code is called
until the authentication is finished. Also, there's currently no
single location that is called in pop3-login code after the
authentication is finished. For example it could be an auth failure
or it could be a successful authentication with a proxying
failure. */
i_free(pop3_client->current_cmd);
return client_auth_begin(client, t_strdup(client->auth_mech_name), ir);
}
bool cmd_user(struct pop3_client *pop3_client, const char *args)
{
if (!client_check_plaintext_auth(&pop3_client->common, FALSE)) {
if (pop3_client->common.virtual_user == NULL)
pop3_client->common.virtual_user = i_strdup(args);
return TRUE;
}
i_free(pop3_client->last_user);
pop3_client->last_user = i_strdup(args);
client_send_raw(&pop3_client->common, "+OK\r\n");
return TRUE;
}
bool cmd_pass(struct pop3_client *pop3_client, const char *args)
{
struct client *client = &pop3_client->common;
string_t *plain_login, *base64;
if (pop3_client->last_user == NULL) {
/* client may ignore the USER reply and only display the error
message from PASS */
if (!client_check_plaintext_auth(client, TRUE))
return TRUE;
client_send_reply(client, POP3_CMD_REPLY_ERROR,
"No username given.");
return TRUE;
}
/* authorization ID \0 authentication ID \0 pass */
plain_login = t_str_new(128);
str_append_c(plain_login, '\0');
str_append(plain_login, pop3_client->last_user);
str_append_c(plain_login, '\0');
str_append(plain_login, args);
i_free_and_null(pop3_client->last_user);
base64 = t_buffer_create(MAX_BASE64_ENCODED_SIZE(plain_login->used));
base64_encode(plain_login->data, plain_login->used, base64);
(void)client_auth_begin(client, "PLAIN", str_c(base64));
return TRUE;
}
bool cmd_apop(struct pop3_client *pop3_client, const char *args)
{
struct client *client = &pop3_client->common;
buffer_t *apop_data, *base64;
const char *p;
unsigned int server_pid, connect_uid;
if (pop3_client->apop_challenge == NULL) {
if (client->set->auth_verbose)
e_info(client->event, "APOP failed: APOP not enabled");
client_send_reply(client, POP3_CMD_REPLY_ERROR,
"APOP not enabled.");
return TRUE;
}
/* <username> <md5 sum in hex> */
p = strchr(args, ' ');
if (p == NULL || strlen(p+1) != 32) {
if (client->set->auth_verbose)
e_info(client->event, "APOP failed: Invalid parameters");
client_send_reply(client, POP3_CMD_REPLY_ERROR,
"Invalid parameters.");
return TRUE;
}
/* APOP challenge \0 username \0 APOP response */
apop_data = t_buffer_create(128);
buffer_append(apop_data, pop3_client->apop_challenge,
strlen(pop3_client->apop_challenge)+1);
buffer_append(apop_data, args, (size_t)(p-args));
buffer_append_c(apop_data, '\0');
if (hex_to_binary(p+1, apop_data) < 0) {
if (client->set->auth_verbose) {
e_info(client->event, "APOP failed: "
"Invalid characters in MD5 response");
}
client_send_reply(client, POP3_CMD_REPLY_ERROR,
"Invalid characters in MD5 response.");
return TRUE;
}
base64 = t_buffer_create(MAX_BASE64_ENCODED_SIZE(apop_data->used));
base64_encode(apop_data->data, apop_data->used, base64);
auth_client_get_connect_id(auth_client, &server_pid, &connect_uid);
if (pop3_client->apop_server_pid != server_pid ||
pop3_client->apop_connect_uid != connect_uid) {
/* we reconnected to auth server and can't authenticate
with APOP in this session anymore. disconnecting the user
is probably the best solution now. */
client_destroy(client,
"Reconnected to auth server, can't do APOP");
return TRUE;
}
(void)client_auth_begin_private(client, "APOP", str_c(base64));
return TRUE;
}
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