dovecot/SOURCES/dovecot-2.3.13-CVE_2020_252...

111 lines
3.3 KiB
Diff

From 9d3ecff3de5553159334cf644e996a616dc52670 Mon Sep 17 00:00:00 2001
From: Timo Sirainen <timo.sirainen@open-xchange.com>
Date: Mon, 17 Aug 2020 18:22:42 +0300
Subject: [PATCH] imap-login: Use imap_parser_read_tag() and
_read_command_name()
---
src/imap-login/imap-login-client.c | 58 ++++++++++++------------------
1 file changed, 23 insertions(+), 35 deletions(-)
diff --git a/src/imap-login/imap-login-client.c b/src/imap-login/imap-login-client.c
index ce5049d567..b2c8af9cbf 100644
--- a/src/imap-login/imap-login-client.c
+++ b/src/imap-login/imap-login-client.c
@@ -196,7 +196,7 @@ static int client_command_execute(struct imap_client *client, const char *cmd,
static bool client_invalid_command(struct imap_client *client)
{
- if (*client->cmd_tag == '\0')
+ if (client->cmd_tag == NULL || *client->cmd_tag == '\0')
client->cmd_tag = "*";
if (++client->common.bad_counter >= CLIENT_MAX_BAD_COMMANDS) {
client_send_reply(&client->common, IMAP_CMD_REPLY_BYE,
@@ -210,33 +210,6 @@ static bool client_invalid_command(struct imap_client *client)
return TRUE;
}
-static bool imap_is_valid_tag(const char *tag)
-{
- for (; *tag != '\0'; tag++) {
- switch (*tag) {
- case '+':
- /* atom-specials: */
- case '(':
- case ')':
- case '{':
- case '/':
- case ' ':
- /* list-wildcards: */
- case '%':
- case '*':
- /* quoted-specials: */
- case '"':
- case '\\':
- return FALSE;
- default:
- if (*tag < ' ') /* CTL */
- return FALSE;
- break;
- }
- }
- return TRUE;
-}
-
static int client_parse_command(struct imap_client *client,
const struct imap_arg **args_r)
{
@@ -261,6 +234,9 @@ static int client_parse_command(struct imap_client *client,
static bool client_handle_input(struct imap_client *client)
{
+ const char *tag, *name;
+ int ret;
+
i_assert(!client->common.authenticating);
if (client->cmd_finished) {
@@ -282,23 +258,35 @@ static bool client_handle_input(struct imap_client *client)
}
if (client->cmd_tag == NULL) {
- client->cmd_tag = imap_parser_read_word(client->parser);
- if (client->cmd_tag == NULL)
+ ret = imap_parser_read_tag(client->parser, &tag);
+ if (ret == 0)
return FALSE; /* need more data */
- if (!imap_is_valid_tag(client->cmd_tag) ||
- strlen(client->cmd_tag) > IMAP_TAG_MAX_LEN) {
+ if (ret < 0 || strlen(tag) > IMAP_TAG_MAX_LEN) {
/* the tag is invalid, don't allow it and don't
send it back. this attempts to prevent any
potentially dangerous replies in case someone tries
to access us using HTTP protocol. */
- client->cmd_tag = "";
+ client->skip_line = TRUE;
+ client->cmd_finished = TRUE;
+ if (!client_invalid_command(client))
+ return FALSE;
+ return client_handle_input(client);
}
+ client->cmd_tag = tag;
}
if (client->cmd_name == NULL) {
- client->cmd_name = imap_parser_read_word(client->parser);
- if (client->cmd_name == NULL)
+ ret = imap_parser_read_command_name(client->parser, &name);
+ if (ret == 0)
return FALSE; /* need more data */
+ if (ret < 0) {
+ client->skip_line = TRUE;
+ client->cmd_finished = TRUE;
+ if (!client_invalid_command(client))
+ return FALSE;
+ return client_handle_input(client);
+ }
+ client->cmd_name = name;
}
return client->common.v.input_next_cmd(&client->common);
}