client-authenticate.c revision 73bfdbe28c2ce6d143eadf0bab8ccfbe4cab0fae
/* Copyright (C) 2002-2004 Timo Sirainen */
#include "common.h"
#include "base64.h"
#include "buffer.h"
#include "ioloop.h"
#include "istream.h"
#include "ostream.h"
#include "safe-memset.h"
#include "str.h"
#include "str-sanitize.h"
#include "imap-parser.h"
#include "auth-client.h"
#include "client.h"
#include "client-authenticate.h"
const char *client_authenticate_get_capabilities(int secured)
{
const struct auth_mech_desc *mech;
unsigned int i, count;
string_t *str;
str = t_str_new(128);
mech = auth_client_get_available_mechs(auth_client, &count);
for (i = 0; i < count; i++) {
/* a) transport is secured
b) auth mechanism isn't plaintext
c) we allow insecure authentication
*/
if ((mech[i].flags & MECH_SEC_PRIVATE) == 0 &&
(secured || !disable_plaintext_auth ||
(mech[i].flags & MECH_SEC_PLAINTEXT) == 0)) {
str_append_c(str, ' ');
str_append(str, "AUTH=");
str_append(str, mech[i].name);
}
}
return str_c(str);
}
static void client_auth_input(void *context)
{
struct imap_client *client = context;
char *line;
if (!client_read(client))
return;
if (client->skip_line) {
if (i_stream_next_line(client->input) == NULL)
return;
client->skip_line = FALSE;
}
/* @UNSAFE */
line = i_stream_next_line(client->input);
if (line == NULL)
return;
if (strcmp(line, "*") == 0) {
sasl_server_auth_cancel(&client->common,
"Authentication aborted");
return;
}
if (client->common.auth_request == NULL) {
sasl_server_auth_cancel(&client->common,
"Don't send unrequested data");
} else {
auth_client_request_continue(client->common.auth_request, line);
}
/* clear sensitive data */
safe_memset(line, 0, strlen(line));
}
static void sasl_callback(struct client *_client, enum sasl_server_reply reply,
const char *data)
{
struct imap_client *client = (struct imap_client *)_client;
struct const_iovec iov[3];
size_t data_len;
ssize_t ret;
switch (reply) {
case SASL_SERVER_REPLY_SUCCESS:
client_send_tagline(client, "OK Logged in.");
client_destroy(client, t_strconcat(
"Login: ", client->common.virtual_user, NULL));
break;
case SASL_SERVER_REPLY_AUTH_FAILED:
if (data == NULL)
client_send_tagline(client, "Authentication failed");
else {
client_send_tagline(client, t_strconcat(
"NO Authentication failed: ", data, NULL));
}
/* get back to normal client input. */
if (client->io != NULL)
io_remove(client->io);
client->io = io_add(client->common.fd, IO_READ,
client_input, client);
break;
case SASL_SERVER_REPLY_MASTER_FAILED:
client_send_line(client, "* BYE Internal login failure. "
"Refer to server log for more information.");
client_destroy(client, t_strconcat("Internal login failure: ",
client->common.virtual_user,
NULL));
break;
case SASL_SERVER_REPLY_CONTINUE:
data_len = strlen(data);
iov[0].iov_base = "+ ";
iov[0].iov_len = 2;
iov[1].iov_base = data;
iov[1].iov_len = data_len;
iov[2].iov_base = "\r\n";
iov[2].iov_len = 2;
ret = o_stream_sendv(client->output, iov, 3);
if (ret < 0)
client_destroy(client, "Disconnected");
else if ((size_t)ret != 2 + data_len + 2)
client_destroy(client, "Transmit buffer full");
else {
/* continue */
return;
}
break;
}
client_unref(client);
}
int cmd_authenticate(struct imap_client *client, struct imap_arg *args)
{
const char *mech_name;
/* we want only one argument: authentication mechanism name */
if (args[0].type != IMAP_ARG_ATOM && args[0].type != IMAP_ARG_STRING)
return -1;
if (args[1].type != IMAP_ARG_EOL)
return -1;
mech_name = IMAP_ARG_STR(&args[0]);
if (*mech_name == '\0')
return FALSE;
client_ref(client);
sasl_server_auth_begin(&client->common, "IMAP", mech_name, NULL,
sasl_callback);
if (!client->common.authenticating)
return 1;
/* following input data will go to authentication */
if (client->io != NULL)
io_remove(client->io);
client->io = io_add(client->common.fd, IO_READ,
client_auth_input, client);
return 0;
}
int cmd_login(struct imap_client *client, struct imap_arg *args)
{
const char *user, *pass;
string_t *plain_login, *base64;
/* two arguments: username and password */
if (args[0].type != IMAP_ARG_ATOM && args[0].type != IMAP_ARG_STRING)
return -1;
if (args[1].type != IMAP_ARG_ATOM && args[1].type != IMAP_ARG_STRING)
return -1;
if (args[2].type != IMAP_ARG_EOL)
return -1;
user = IMAP_ARG_STR(&args[0]);
pass = IMAP_ARG_STR(&args[1]);
if (!client->common.secured && disable_plaintext_auth) {
if (verbose_auth) {
client_syslog(&client->common, "Login failed: "
"Plaintext authentication disabled");
}
client_send_line(client,
"* BAD [ALERT] Plaintext authentication is disabled, "
"but your client sent password in plaintext anyway. "
"If anyone was listening, the password was exposed.");
client_send_tagline(client,
"NO Plaintext authentication disabled.");
return 1;
}
/* authorization ID \0 authentication ID \0 pass */
plain_login = buffer_create_dynamic(pool_datastack_create(), 64);
buffer_append_c(plain_login, '\0');
buffer_append(plain_login, user, strlen(user));
buffer_append_c(plain_login, '\0');
buffer_append(plain_login, pass, strlen(pass));
base64 = buffer_create_dynamic(pool_datastack_create(),
MAX_BASE64_ENCODED_SIZE(plain_login->used));
base64_encode(plain_login->data, plain_login->used, base64);
client_ref(client);
sasl_server_auth_begin(&client->common, "IMAP", "PLAIN",
str_c(base64), sasl_callback);
if (!client->common.authenticating)
return 1;
/* don't read any input from client until login is finished */
if (client->io != NULL) {
io_remove(client->io);
client->io = NULL;
}
return 0;
}