blob: 6d4eed3d73333f2fe1bc3d2702634be882575c66 [file] [log] [blame]
/*
* ACL management functions.
*
* Copyright 2000-2011 Willy Tarreau <w@1wt.eu>
*
* 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.
*
*/
#include <ctype.h>
#include <stdio.h>
#include <string.h>
#include <common/config.h>
#include <common/mini-clist.h>
#include <common/standard.h>
#include <common/uri_auth.h>
#include <types/global.h>
#include <proto/acl.h>
#include <proto/auth.h>
#include <proto/buffers.h>
#include <proto/log.h>
#include <proto/proxy.h>
#include <ebsttree.h>
/* The capabilities of filtering hooks describe the type of information
* available to each of them.
*/
const unsigned int filt_cap[] = {
[ACL_HOOK_REQ_FE_TCP] = ACL_USE_TCP4_ANY|ACL_USE_TCP6_ANY|ACL_USE_TCP_ANY,
[ACL_HOOK_REQ_FE_TCP_CONTENT] = ACL_USE_TCP4_ANY|ACL_USE_TCP6_ANY|ACL_USE_TCP_ANY|ACL_USE_L6REQ_ANY,
[ACL_HOOK_REQ_FE_HTTP_IN] = ACL_USE_TCP4_ANY|ACL_USE_TCP6_ANY|ACL_USE_TCP_ANY|ACL_USE_L6REQ_ANY|ACL_USE_L7REQ_ANY|ACL_USE_HDR_ANY,
[ACL_HOOK_REQ_FE_SWITCH] = ACL_USE_TCP4_ANY|ACL_USE_TCP6_ANY|ACL_USE_TCP_ANY|ACL_USE_L6REQ_ANY|ACL_USE_L7REQ_ANY|ACL_USE_HDR_ANY,
[ACL_HOOK_REQ_BE_TCP_CONTENT] = ACL_USE_TCP4_ANY|ACL_USE_TCP6_ANY|ACL_USE_TCP_ANY|ACL_USE_L6REQ_ANY|ACL_USE_L7REQ_ANY|ACL_USE_HDR_ANY,
[ACL_HOOK_REQ_BE_HTTP_IN] = ACL_USE_TCP4_ANY|ACL_USE_TCP6_ANY|ACL_USE_TCP_ANY|ACL_USE_L6REQ_ANY|ACL_USE_L7REQ_ANY|ACL_USE_HDR_ANY,
[ACL_HOOK_REQ_BE_SWITCH] = ACL_USE_TCP4_ANY|ACL_USE_TCP6_ANY|ACL_USE_TCP_ANY|ACL_USE_L6REQ_ANY|ACL_USE_L7REQ_ANY|ACL_USE_HDR_ANY,
[ACL_HOOK_REQ_FE_HTTP_OUT] = ACL_USE_TCP4_ANY|ACL_USE_TCP6_ANY|ACL_USE_TCP_ANY|ACL_USE_L6REQ_ANY|ACL_USE_L7REQ_ANY|ACL_USE_HDR_ANY,
[ACL_HOOK_REQ_BE_HTTP_OUT] = ACL_USE_TCP4_ANY|ACL_USE_TCP6_ANY|ACL_USE_TCP_ANY|ACL_USE_L6REQ_ANY|ACL_USE_L7REQ_ANY|ACL_USE_HDR_ANY,
[ACL_HOOK_RTR_BE_TCP_CONTENT] = ACL_USE_REQ_PERMANENT|ACL_USE_REQ_CACHEABLE|ACL_USE_L6RTR_ANY,
[ACL_HOOK_RTR_BE_HTTP_IN] = ACL_USE_REQ_PERMANENT|ACL_USE_REQ_CACHEABLE|ACL_USE_L6RTR_ANY|ACL_USE_L7RTR_ANY,
[ACL_HOOK_RTR_FE_TCP_CONTENT] = ACL_USE_REQ_PERMANENT|ACL_USE_REQ_CACHEABLE|ACL_USE_L6RTR_ANY|ACL_USE_L7RTR_ANY,
[ACL_HOOK_RTR_FE_HTTP_IN] = ACL_USE_REQ_PERMANENT|ACL_USE_REQ_CACHEABLE|ACL_USE_L6RTR_ANY|ACL_USE_L7RTR_ANY,
[ACL_HOOK_RTR_BE_HTTP_OUT] = ACL_USE_REQ_PERMANENT|ACL_USE_REQ_CACHEABLE|ACL_USE_L6RTR_ANY|ACL_USE_L7RTR_ANY,
[ACL_HOOK_RTR_FE_HTTP_OUT] = ACL_USE_REQ_PERMANENT|ACL_USE_REQ_CACHEABLE|ACL_USE_L6RTR_ANY|ACL_USE_L7RTR_ANY,
};
/* List head of all known ACL keywords */
static struct acl_kw_list acl_keywords = {
.list = LIST_HEAD_INIT(acl_keywords.list)
};
/*
* These functions are only used for debugging complex configurations.
*/
/* force TRUE to be returned at the fetch level */
static int
acl_fetch_true(struct proxy *px, struct session *l4, void *l7, int dir,
struct acl_expr *expr, struct acl_test *test)
{
test->flags |= ACL_TEST_F_SET_RES_PASS;
return 1;
}
/* wait for more data as long as possible, then return TRUE. This should be
* used with content inspection.
*/
static int
acl_fetch_wait_end(struct proxy *px, struct session *l4, void *l7, int dir,
struct acl_expr *expr, struct acl_test *test)
{
if (dir & ACL_PARTIAL) {
test->flags |= ACL_TEST_F_MAY_CHANGE;
return 0;
}
test->flags |= ACL_TEST_F_SET_RES_PASS;
return 1;
}
/* force FALSE to be returned at the fetch level */
static int
acl_fetch_false(struct proxy *px, struct session *l4, void *l7, int dir,
struct acl_expr *expr, struct acl_test *test)
{
test->flags |= ACL_TEST_F_SET_RES_FAIL;
return 1;
}
/* return the number of bytes in the request buffer */
static int
acl_fetch_req_len(struct proxy *px, struct session *l4, void *l7, int dir,
struct acl_expr *expr, struct acl_test *test)
{
if (!l4 || !l4->req)
return 0;
temp_pattern.data.integer = l4->req->l;
test->flags = ACL_TEST_F_VOLATILE | ACL_TEST_F_MAY_CHANGE;
return 1;
}
static int
acl_fetch_ssl_hello_type(struct proxy *px, struct session *l4, void *l7, int dir,
struct acl_expr *expr, struct acl_test *test)
{
int hs_len;
int hs_type, bleft;
struct buffer *b;
const unsigned char *data;
if (!l4)
goto not_ssl_hello;
b = ((dir & ACL_DIR_MASK) == ACL_DIR_RTR) ? l4->rep : l4->req;
bleft = b->l;
data = (const unsigned char *)b->w;
if (!bleft)
goto too_short;
if ((*data >= 0x14 && *data <= 0x17) || (*data == 0xFF)) {
/* SSLv3 header format */
if (bleft < 9)
goto too_short;
/* ssl version 3 */
if ((data[1] << 16) + data[2] < 0x00030000)
goto not_ssl_hello;
/* ssl message len must present handshake type and len */
if ((data[3] << 8) + data[4] < 4)
goto not_ssl_hello;
/* format introduced with SSLv3 */
hs_type = (int)data[5];
hs_len = ( data[6] << 16 ) + ( data[7] << 8 ) + data[8];
/* not a full handshake */
if (bleft < (9 + hs_len))
goto too_short;
}
else {
goto not_ssl_hello;
}
temp_pattern.data.integer = hs_type;
test->flags = ACL_TEST_F_VOLATILE;
return 1;
too_short:
test->flags = ACL_TEST_F_MAY_CHANGE;
not_ssl_hello:
return 0;
}
/* Return the version of the SSL protocol in the request. It supports both
* SSLv3 (TLSv1) header format for any message, and SSLv2 header format for
* the hello message. The SSLv3 format is described in RFC 2246 p49, and the
* SSLv2 format is described here, and completed p67 of RFC 2246 :
* http://wp.netscape.com/eng/security/SSL_2.html
*
* Note: this decoder only works with non-wrapping data.
*/
static int
acl_fetch_req_ssl_ver(struct proxy *px, struct session *l4, void *l7, int dir,
struct acl_expr *expr, struct acl_test *test)
{
int version, bleft, msg_len;
const unsigned char *data;
if (!l4 || !l4->req)
return 0;
msg_len = 0;
bleft = l4->req->l;
if (!bleft)
goto too_short;
data = (const unsigned char *)l4->req->w;
if ((*data >= 0x14 && *data <= 0x17) || (*data == 0xFF)) {
/* SSLv3 header format */
if (bleft < 5)
goto too_short;
version = (data[1] << 16) + data[2]; /* version: major, minor */
msg_len = (data[3] << 8) + data[4]; /* record length */
/* format introduced with SSLv3 */
if (version < 0x00030000)
goto not_ssl;
/* message length between 1 and 2^14 + 2048 */
if (msg_len < 1 || msg_len > ((1<<14) + 2048))
goto not_ssl;
bleft -= 5; data += 5;
} else {
/* SSLv2 header format, only supported for hello (msg type 1) */
int rlen, plen, cilen, silen, chlen;
if (*data & 0x80) {
if (bleft < 3)
goto too_short;
/* short header format : 15 bits for length */
rlen = ((data[0] & 0x7F) << 8) | data[1];
plen = 0;
bleft -= 2; data += 2;
} else {
if (bleft < 4)
goto too_short;
/* long header format : 14 bits for length + pad length */
rlen = ((data[0] & 0x3F) << 8) | data[1];
plen = data[2];
bleft -= 3; data += 2;
}
if (*data != 0x01)
goto not_ssl;
bleft--; data++;
if (bleft < 8)
goto too_short;
version = (data[0] << 16) + data[1]; /* version: major, minor */
cilen = (data[2] << 8) + data[3]; /* cipher len, multiple of 3 */
silen = (data[4] << 8) + data[5]; /* session_id_len: 0 or 16 */
chlen = (data[6] << 8) + data[7]; /* 16<=challenge length<=32 */
bleft -= 8; data += 8;
if (cilen % 3 != 0)
goto not_ssl;
if (silen && silen != 16)
goto not_ssl;
if (chlen < 16 || chlen > 32)
goto not_ssl;
if (rlen != 9 + cilen + silen + chlen)
goto not_ssl;
/* focus on the remaining data length */
msg_len = cilen + silen + chlen + plen;
}
/* We could recursively check that the buffer ends exactly on an SSL
* fragment boundary and that a possible next segment is still SSL,
* but that's a bit pointless. However, we could still check that
* all the part of the request which fits in a buffer is already
* there.
*/
if (msg_len > buffer_max_len(l4->req) + l4->req->data - l4->req->w)
msg_len = buffer_max_len(l4->req) + l4->req->data - l4->req->w;
if (bleft < msg_len)
goto too_short;
/* OK that's enough. We have at least the whole message, and we have
* the protocol version.
*/
temp_pattern.data.integer = version;
test->flags = ACL_TEST_F_VOLATILE;
return 1;
too_short:
test->flags = ACL_TEST_F_MAY_CHANGE;
not_ssl:
return 0;
}
/* Try to extract the Server Name Indication that may be presented in a TLS
* client hello handshake message. The format of the message is the following
* (cf RFC5246 + RFC6066) :
* TLS frame :
* - uint8 type = 0x16 (Handshake)
* - uint16 version >= 0x0301 (TLSv1)
* - uint16 length (frame length)
* - TLS handshake :
* - uint8 msg_type = 0x01 (ClientHello)
* - uint24 length (handshake message length)
* - ClientHello :
* - uint16 client_version >= 0x0301 (TLSv1)
* - uint8 Random[32]
* - SessionID :
* - uint8 session_id_len (0..32) (SessionID len in bytes)
* - uint8 session_id[session_id_len]
* - CipherSuite :
* - uint16 cipher_len >= 2 (Cipher length in bytes)
* - uint16 ciphers[cipher_len/2]
* - CompressionMethod :
* - uint8 compression_len >= 1 (# of supported methods)
* - uint8 compression_methods[compression_len]
* - optional client_extension_len (in bytes)
* - optional sequence of ClientHelloExtensions (as many bytes as above):
* - uint16 extension_type = 0 for server_name
* - uint16 extension_len
* - opaque extension_data[extension_len]
* - uint16 server_name_list_len (# of bytes here)
* - opaque server_names[server_name_list_len bytes]
* - uint8 name_type = 0 for host_name
* - uint16 name_len
* - opaque hostname[name_len bytes]
*/
static int
acl_fetch_ssl_hello_sni(struct proxy *px, struct session *l4, void *l7, int dir,
struct acl_expr *expr, struct acl_test *test)
{
int hs_len, ext_len, bleft;
struct buffer *b;
unsigned char *data;
if (!l4)
goto not_ssl_hello;
b = ((dir & ACL_DIR_MASK) == ACL_DIR_RTR) ? l4->rep : l4->req;
bleft = b->l;
data = (unsigned char *)b->w;
/* Check for SSL/TLS Handshake */
if (!bleft)
goto too_short;
if (*data != 0x16)
goto not_ssl_hello;
/* Check for TLSv1 or later (SSL version >= 3.1) */
if (bleft < 3)
goto too_short;
if (data[1] < 0x03 || data[2] < 0x01)
goto not_ssl_hello;
if (bleft < 5)
goto too_short;
hs_len = (data[3] << 8) + data[4];
if (hs_len < 1 + 3 + 2 + 32 + 1 + 2 + 2 + 1 + 1 + 2 + 2)
goto not_ssl_hello; /* too short to have an extension */
data += 5; /* enter TLS handshake */
bleft -= 5;
/* Check for a complete client hello starting at <data> */
if (bleft < 1)
goto too_short;
if (data[0] != 0x01) /* msg_type = Client Hello */
goto not_ssl_hello;
/* Check the Hello's length */
if (bleft < 4)
goto too_short;
hs_len = (data[1] << 16) + (data[2] << 8) + data[3];
if (hs_len < 2 + 32 + 1 + 2 + 2 + 1 + 1 + 2 + 2)
goto not_ssl_hello; /* too short to have an extension */
/* We want the full handshake here */
if (bleft < hs_len)
goto too_short;
data += 4;
/* Start of the ClientHello message */
if (data[0] < 0x03 || data[1] < 0x01) /* TLSv1 minimum */
goto not_ssl_hello;
ext_len = data[35];
if (ext_len > 32 || ext_len > (hs_len - 35)) /* check for correct session_id len */
goto not_ssl_hello;
/* Jump to cipher suite */
hs_len -= 35 + ext_len;
data += 35 + ext_len;
if (hs_len < 4 || /* minimum one cipher */
(ext_len = (data[0] << 8) + data[1]) < 2 || /* minimum 2 bytes for a cipher */
ext_len > hs_len)
goto not_ssl_hello;
/* Jump to the compression methods */
hs_len -= 2 + ext_len;
data += 2 + ext_len;
if (hs_len < 2 || /* minimum one compression method */
data[0] < 1 || data[0] > hs_len) /* minimum 1 bytes for a method */
goto not_ssl_hello;
/* Jump to the extensions */
hs_len -= 1 + data[0];
data += 1 + data[0];
if (hs_len < 2 || /* minimum one extension list length */
(ext_len = (data[0] << 8) + data[1]) > hs_len - 2) /* list too long */
goto not_ssl_hello;
hs_len = ext_len; /* limit ourselves to the extension length */
data += 2;
while (hs_len >= 4) {
int ext_type, name_type, srv_len, name_len;
ext_type = (data[0] << 8) + data[1];
ext_len = (data[2] << 8) + data[3];
if (ext_len > hs_len - 4) /* Extension too long */
goto not_ssl_hello;
if (ext_type == 0) { /* Server name */
if (ext_len < 2) /* need one list length */
goto not_ssl_hello;
srv_len = (data[4] << 8) + data[5];
if (srv_len < 4 || srv_len > hs_len - 6)
goto not_ssl_hello; /* at least 4 bytes per server name */
name_type = data[6];
name_len = (data[7] << 8) + data[8];
if (name_type == 0) { /* hostname */
temp_pattern.data.str.str = (char *)data + 9;
temp_pattern.data.str.len = name_len;
test->flags = ACL_TEST_F_VOLATILE;
return 1;
}
}
hs_len -= 4 + ext_len;
data += 4 + ext_len;
}
/* server name not found */
goto not_ssl_hello;
too_short:
test->flags = ACL_TEST_F_MAY_CHANGE;
not_ssl_hello:
return 0;
}
/* Fetch the RDP cookie identified in the expression.
* Note: this decoder only works with non-wrapping data.
*/
int
acl_fetch_rdp_cookie(struct proxy *px, struct session *l4, void *l7, int dir,
struct acl_expr *expr, struct acl_test *test)
{
int bleft;
const unsigned char *data;
if (!l4 || !l4->req)
return 0;
test->flags = 0;
bleft = l4->req->l;
if (bleft <= 11)
goto too_short;
data = (const unsigned char *)l4->req->w + 11;
bleft -= 11;
if (bleft <= 7)
goto too_short;
if (strncasecmp((const char *)data, "Cookie:", 7) != 0)
goto not_cookie;
data += 7;
bleft -= 7;
while (bleft > 0 && *data == ' ') {
data++;
bleft--;
}
if (expr->arg_len) {
if (bleft <= expr->arg_len)
goto too_short;
if ((data[expr->arg_len] != '=') ||
strncasecmp(expr->arg.str, (const char *)data, expr->arg_len) != 0)
goto not_cookie;
data += expr->arg_len + 1;
bleft -= expr->arg_len + 1;
} else {
while (bleft > 0 && *data != '=') {
if (*data == '\r' || *data == '\n')
goto not_cookie;
data++;
bleft--;
}
if (bleft < 1)
goto too_short;
if (*data != '=')
goto not_cookie;
data++;
bleft--;
}
/* data points to cookie value */
temp_pattern.data.str.str = (char *)data;
temp_pattern.data.str.len = 0;
while (bleft > 0 && *data != '\r') {
data++;
bleft--;
}
if (bleft < 2)
goto too_short;
if (data[0] != '\r' || data[1] != '\n')
goto not_cookie;
temp_pattern.data.str.len = (char *)data - temp_pattern.data.str.str;
test->flags = ACL_TEST_F_VOLATILE;
return 1;
too_short:
test->flags = ACL_TEST_F_MAY_CHANGE;
not_cookie:
return 0;
}
static int
acl_fetch_rdp_cookie_cnt(struct proxy *px, struct session *l4, void *l7, int dir,
struct acl_expr *expr, struct acl_test *test)
{
int ret;
ret = acl_fetch_rdp_cookie(px, l4, l7, dir, expr, test);
temp_pattern.data.str.str = NULL;
temp_pattern.data.str.len = 0;
if (test->flags & ACL_TEST_F_MAY_CHANGE)
return 0;
test->flags = ACL_TEST_F_VOLATILE;
temp_pattern.data.integer = ret;
return 1;
}
/*
* These functions are exported and may be used by any other component.
*/
/* ignore the current line */
int acl_parse_nothing(const char **text, struct acl_pattern *pattern, int *opaque)
{
return 1;
}
/* always fake a data retrieval */
int acl_fetch_nothing(struct proxy *px, struct session *l4, void *l7, int dir,
struct acl_expr *expr, struct acl_test *test)
{
return 1;
}
/* always return false */
int acl_match_nothing(struct acl_test *test, struct acl_pattern *pattern)
{
return ACL_PAT_FAIL;
}
/* NB: For two strings to be identical, it is required that their lengths match */
int acl_match_str(struct acl_test *test, struct acl_pattern *pattern)
{
int icase;
if (pattern->len != temp_pattern.data.str.len)
return ACL_PAT_FAIL;
icase = pattern->flags & ACL_PAT_F_IGNORE_CASE;
if ((icase && strncasecmp(pattern->ptr.str, temp_pattern.data.str.str, temp_pattern.data.str.len) == 0) ||
(!icase && strncmp(pattern->ptr.str, temp_pattern.data.str.str, temp_pattern.data.str.len) == 0))
return ACL_PAT_PASS;
return ACL_PAT_FAIL;
}
/* Lookup a string in the expression's pattern tree. The node is returned if it
* exists, otherwise NULL.
*/
void *acl_lookup_str(struct acl_test *test, struct acl_expr *expr)
{
/* data are stored in a tree */
struct ebmb_node *node;
char prev;
/* we may have to force a trailing zero on the test pattern */
prev = temp_pattern.data.str.str[temp_pattern.data.str.len];
if (prev)
temp_pattern.data.str.str[temp_pattern.data.str.len] = '\0';
node = ebst_lookup(&expr->pattern_tree, temp_pattern.data.str.str);
if (prev)
temp_pattern.data.str.str[temp_pattern.data.str.len] = prev;
return node;
}
/* Executes a regex. It needs to change the data. If it is marked READ_ONLY
* then it will be allocated and duplicated in place so that others may use
* it later on. Note that this is embarrassing because we always try to avoid
* allocating memory at run time.
*/
int acl_match_reg(struct acl_test *test, struct acl_pattern *pattern)
{
char old_char;
int ret;
if (unlikely(test->flags & ACL_TEST_F_READ_ONLY)) {
char *new_str;
new_str = calloc(1, temp_pattern.data.str.len + 1);
if (!new_str)
return ACL_PAT_FAIL;
memcpy(new_str, temp_pattern.data.str.str, temp_pattern.data.str.len);
new_str[temp_pattern.data.str.len] = 0;
if (test->flags & ACL_TEST_F_MUST_FREE)
free(temp_pattern.data.str.str);
temp_pattern.data.str.str = new_str;
test->flags |= ACL_TEST_F_MUST_FREE;
test->flags &= ~ACL_TEST_F_READ_ONLY;
}
old_char = temp_pattern.data.str.str[temp_pattern.data.str.len];
temp_pattern.data.str.str[temp_pattern.data.str.len] = 0;
if (regexec(pattern->ptr.reg, temp_pattern.data.str.str, 0, NULL, 0) == 0)
ret = ACL_PAT_PASS;
else
ret = ACL_PAT_FAIL;
temp_pattern.data.str.str[temp_pattern.data.str.len] = old_char;
return ret;
}
/* Checks that the pattern matches the beginning of the tested string. */
int acl_match_beg(struct acl_test *test, struct acl_pattern *pattern)
{
int icase;
if (pattern->len > temp_pattern.data.str.len)
return ACL_PAT_FAIL;
icase = pattern->flags & ACL_PAT_F_IGNORE_CASE;
if ((icase && strncasecmp(pattern->ptr.str, temp_pattern.data.str.str, pattern->len) != 0) ||
(!icase && strncmp(pattern->ptr.str, temp_pattern.data.str.str, pattern->len) != 0))
return ACL_PAT_FAIL;
return ACL_PAT_PASS;
}
/* Checks that the pattern matches the end of the tested string. */
int acl_match_end(struct acl_test *test, struct acl_pattern *pattern)
{
int icase;
if (pattern->len > temp_pattern.data.str.len)
return ACL_PAT_FAIL;
icase = pattern->flags & ACL_PAT_F_IGNORE_CASE;
if ((icase && strncasecmp(pattern->ptr.str, temp_pattern.data.str.str + temp_pattern.data.str.len - pattern->len, pattern->len) != 0) ||
(!icase && strncmp(pattern->ptr.str, temp_pattern.data.str.str + temp_pattern.data.str.len - pattern->len, pattern->len) != 0))
return ACL_PAT_FAIL;
return ACL_PAT_PASS;
}
/* Checks that the pattern is included inside the tested string.
* NB: Suboptimal, should be rewritten using a Boyer-Moore method.
*/
int acl_match_sub(struct acl_test *test, struct acl_pattern *pattern)
{
int icase;
char *end;
char *c;
if (pattern->len > temp_pattern.data.str.len)
return ACL_PAT_FAIL;
end = temp_pattern.data.str.str + temp_pattern.data.str.len - pattern->len;
icase = pattern->flags & ACL_PAT_F_IGNORE_CASE;
if (icase) {
for (c = temp_pattern.data.str.str; c <= end; c++) {
if (tolower(*c) != tolower(*pattern->ptr.str))
continue;
if (strncasecmp(pattern->ptr.str, c, pattern->len) == 0)
return ACL_PAT_PASS;
}
} else {
for (c = temp_pattern.data.str.str; c <= end; c++) {
if (*c != *pattern->ptr.str)
continue;
if (strncmp(pattern->ptr.str, c, pattern->len) == 0)
return ACL_PAT_PASS;
}
}
return ACL_PAT_FAIL;
}
/* Background: Fast way to find a zero byte in a word
* http://graphics.stanford.edu/~seander/bithacks.html#ZeroInWord
* hasZeroByte = (v - 0x01010101UL) & ~v & 0x80808080UL;
*
* To look for 4 different byte values, xor the word with those bytes and
* then check for zero bytes:
*
* v = (((unsigned char)c * 0x1010101U) ^ delimiter)
* where <delimiter> is the 4 byte values to look for (as an uint)
* and <c> is the character that is being tested
*/
static inline unsigned int is_delimiter(unsigned char c, unsigned int mask)
{
mask ^= (c * 0x01010101); /* propagate the char to all 4 bytes */
return (mask - 0x01010101) & ~mask & 0x80808080U;
}
static inline unsigned int make_4delim(unsigned char d1, unsigned char d2, unsigned char d3, unsigned char d4)
{
return d1 << 24 | d2 << 16 | d3 << 8 | d4;
}
/* This one is used by other real functions. It checks that the pattern is
* included inside the tested string, but enclosed between the specified
* delimiters or at the beginning or end of the string. The delimiters are
* provided as an unsigned int made by make_4delim() and match up to 4 different
* delimiters. Delimiters are stripped at the beginning and end of the pattern.
*/
static int match_word(struct acl_test *test, struct acl_pattern *pattern, unsigned int delimiters)
{
int may_match, icase;
char *c, *end;
char *ps;
int pl;
pl = pattern->len;
ps = pattern->ptr.str;
while (pl > 0 && is_delimiter(*ps, delimiters)) {
pl--;
ps++;
}
while (pl > 0 && is_delimiter(ps[pl - 1], delimiters))
pl--;
if (pl > temp_pattern.data.str.len)
return ACL_PAT_FAIL;
may_match = 1;
icase = pattern->flags & ACL_PAT_F_IGNORE_CASE;
end = temp_pattern.data.str.str + temp_pattern.data.str.len - pl;
for (c = temp_pattern.data.str.str; c <= end; c++) {
if (is_delimiter(*c, delimiters)) {
may_match = 1;
continue;
}
if (!may_match)
continue;
if (icase) {
if ((tolower(*c) == tolower(*ps)) &&
(strncasecmp(ps, c, pl) == 0) &&
(c == end || is_delimiter(c[pl], delimiters)))
return ACL_PAT_PASS;
} else {
if ((*c == *ps) &&
(strncmp(ps, c, pl) == 0) &&
(c == end || is_delimiter(c[pl], delimiters)))
return ACL_PAT_PASS;
}
may_match = 0;
}
return ACL_PAT_FAIL;
}
/* Checks that the pattern is included inside the tested string, but enclosed
* between the delimiters '?' or '/' or at the beginning or end of the string.
* Delimiters at the beginning or end of the pattern are ignored.
*/
int acl_match_dir(struct acl_test *test, struct acl_pattern *pattern)
{
return match_word(test, pattern, make_4delim('/', '?', '?', '?'));
}
/* Checks that the pattern is included inside the tested string, but enclosed
* between the delmiters '/', '?', '.' or ":" or at the beginning or end of
* the string. Delimiters at the beginning or end of the pattern are ignored.
*/
int acl_match_dom(struct acl_test *test, struct acl_pattern *pattern)
{
return match_word(test, pattern, make_4delim('/', '?', '.', ':'));
}
/* Checks that the integer in <test> is included between min and max */
int acl_match_int(struct acl_test *test, struct acl_pattern *pattern)
{
if ((!pattern->val.range.min_set || pattern->val.range.min <= temp_pattern.data.integer) &&
(!pattern->val.range.max_set || temp_pattern.data.integer <= pattern->val.range.max))
return ACL_PAT_PASS;
return ACL_PAT_FAIL;
}
/* Checks that the length of the pattern in <test> is included between min and max */
int acl_match_len(struct acl_test *test, struct acl_pattern *pattern)
{
if ((!pattern->val.range.min_set || pattern->val.range.min <= temp_pattern.data.str.len) &&
(!pattern->val.range.max_set || temp_pattern.data.str.len <= pattern->val.range.max))
return ACL_PAT_PASS;
return ACL_PAT_FAIL;
}
int acl_match_ip(struct acl_test *test, struct acl_pattern *pattern)
{
struct in_addr *s;
if (temp_pattern.type != PATTERN_TYPE_IP)
return ACL_PAT_FAIL;
s = &temp_pattern.data.ip;
if (((s->s_addr ^ pattern->val.ipv4.addr.s_addr) & pattern->val.ipv4.mask.s_addr) == 0)
return ACL_PAT_PASS;
return ACL_PAT_FAIL;
}
/* Lookup an IPv4 address in the expression's pattern tree using the longest
* match method. The node is returned if it exists, otherwise NULL.
*/
void *acl_lookup_ip(struct acl_test *test, struct acl_expr *expr)
{
struct in_addr *s;
if (temp_pattern.type != PATTERN_TYPE_IP)
return ACL_PAT_FAIL;
s = &temp_pattern.data.ip;
return ebmb_lookup_longest(&expr->pattern_tree, &s->s_addr);
}
/* Parse a string. It is allocated and duplicated. */
int acl_parse_str(const char **text, struct acl_pattern *pattern, int *opaque)
{
int len;
len = strlen(*text);
if (pattern->flags & ACL_PAT_F_TREE_OK) {
/* we're allowed to put the data in a tree whose root is pointed
* to by val.tree.
*/
struct ebmb_node *node;
node = calloc(1, sizeof(*node) + len + 1);
if (!node)
return 0;
memcpy(node->key, *text, len + 1);
if (ebst_insert(pattern->val.tree, node) != node)
free(node); /* was a duplicate */
pattern->flags |= ACL_PAT_F_TREE; /* this pattern now contains a tree */
return 1;
}
pattern->ptr.str = strdup(*text);
if (!pattern->ptr.str)
return 0;
pattern->len = len;
return 1;
}
/* Parse and concatenate all further strings into one. */
int
acl_parse_strcat(const char **text, struct acl_pattern *pattern, int *opaque)
{
int len = 0, i;
char *s;
for (i = 0; *text[i]; i++)
len += strlen(text[i])+1;
pattern->ptr.str = s = calloc(1, len);
if (!pattern->ptr.str)
return 0;
for (i = 0; *text[i]; i++)
s += sprintf(s, i?" %s":"%s", text[i]);
pattern->len = len;
return i;
}
/* Free data allocated by acl_parse_reg */
static void acl_free_reg(void *ptr) {
regfree((regex_t *)ptr);
}
/* Parse a regex. It is allocated. */
int acl_parse_reg(const char **text, struct acl_pattern *pattern, int *opaque)
{
regex_t *preg;
int icase;
preg = calloc(1, sizeof(regex_t));
if (!preg)
return 0;
icase = (pattern->flags & ACL_PAT_F_IGNORE_CASE) ? REG_ICASE : 0;
if (regcomp(preg, *text, REG_EXTENDED | REG_NOSUB | icase) != 0) {
free(preg);
return 0;
}
pattern->ptr.reg = preg;
pattern->freeptrbuf = &acl_free_reg;
return 1;
}
/* Parse a range of positive integers delimited by either ':' or '-'. If only
* one integer is read, it is set as both min and max. An operator may be
* specified as the prefix, among this list of 5 :
*
* 0:eq, 1:gt, 2:ge, 3:lt, 4:le
*
* The default operator is "eq". It supports range matching. Ranges are
* rejected for other operators. The operator may be changed at any time.
* The operator is stored in the 'opaque' argument.
*
*/
int acl_parse_int(const char **text, struct acl_pattern *pattern, int *opaque)
{
signed long long i;
unsigned int j, last, skip = 0;
const char *ptr = *text;
while (!isdigit((unsigned char)*ptr)) {
switch (get_std_op(ptr)) {
case STD_OP_EQ: *opaque = 0; break;
case STD_OP_GT: *opaque = 1; break;
case STD_OP_GE: *opaque = 2; break;
case STD_OP_LT: *opaque = 3; break;
case STD_OP_LE: *opaque = 4; break;
default:
return 0;
}
skip++;
ptr = text[skip];
}
last = i = 0;
while (1) {
j = *ptr++;
if ((j == '-' || j == ':') && !last) {
last++;
pattern->val.range.min = i;
i = 0;
continue;
}
j -= '0';
if (j > 9)
// also catches the terminating zero
break;
i *= 10;
i += j;
}
if (last && *opaque >= 1 && *opaque <= 4)
/* having a range with a min or a max is absurd */
return 0;
if (!last)
pattern->val.range.min = i;
pattern->val.range.max = i;
switch (*opaque) {
case 0: /* eq */
pattern->val.range.min_set = 1;
pattern->val.range.max_set = 1;
break;
case 1: /* gt */
pattern->val.range.min++; /* gt = ge + 1 */
case 2: /* ge */
pattern->val.range.min_set = 1;
pattern->val.range.max_set = 0;
break;
case 3: /* lt */
pattern->val.range.max--; /* lt = le - 1 */
case 4: /* le */
pattern->val.range.min_set = 0;
pattern->val.range.max_set = 1;
break;
}
return skip + 1;
}
/* Parse a range of positive 2-component versions delimited by either ':' or
* '-'. The version consists in a major and a minor, both of which must be
* smaller than 65536, because internally they will be represented as a 32-bit
* integer.
* If only one version is read, it is set as both min and max. Just like for
* pure integers, an operator may be specified as the prefix, among this list
* of 5 :
*
* 0:eq, 1:gt, 2:ge, 3:lt, 4:le
*
* The default operator is "eq". It supports range matching. Ranges are
* rejected for other operators. The operator may be changed at any time.
* The operator is stored in the 'opaque' argument. This allows constructs
* such as the following one :
*
* acl obsolete_ssl ssl_req_proto lt 3
* acl unsupported_ssl ssl_req_proto gt 3.1
* acl valid_ssl ssl_req_proto 3.0-3.1
*
*/
int acl_parse_dotted_ver(const char **text, struct acl_pattern *pattern, int *opaque)
{
signed long long i;
unsigned int j, last, skip = 0;
const char *ptr = *text;
while (!isdigit((unsigned char)*ptr)) {
switch (get_std_op(ptr)) {
case STD_OP_EQ: *opaque = 0; break;
case STD_OP_GT: *opaque = 1; break;
case STD_OP_GE: *opaque = 2; break;
case STD_OP_LT: *opaque = 3; break;
case STD_OP_LE: *opaque = 4; break;
default:
return 0;
}
skip++;
ptr = text[skip];
}
last = i = 0;
while (1) {
j = *ptr++;
if (j == '.') {
/* minor part */
if (i >= 65536)
return 0;
i <<= 16;
continue;
}
if ((j == '-' || j == ':') && !last) {
last++;
if (i < 65536)
i <<= 16;
pattern->val.range.min = i;
i = 0;
continue;
}
j -= '0';
if (j > 9)
// also catches the terminating zero
break;
i = (i & 0xFFFF0000) + (i & 0xFFFF) * 10;
i += j;
}
/* if we only got a major version, let's shift it now */
if (i < 65536)
i <<= 16;
if (last && *opaque >= 1 && *opaque <= 4)
/* having a range with a min or a max is absurd */
return 0;
if (!last)
pattern->val.range.min = i;
pattern->val.range.max = i;
switch (*opaque) {
case 0: /* eq */
pattern->val.range.min_set = 1;
pattern->val.range.max_set = 1;
break;
case 1: /* gt */
pattern->val.range.min++; /* gt = ge + 1 */
case 2: /* ge */
pattern->val.range.min_set = 1;
pattern->val.range.max_set = 0;
break;
case 3: /* lt */
pattern->val.range.max--; /* lt = le - 1 */
case 4: /* le */
pattern->val.range.min_set = 0;
pattern->val.range.max_set = 1;
break;
}
return skip + 1;
}
/* Parse an IP address and an optional mask in the form addr[/mask].
* The addr may either be an IPv4 address or a hostname. The mask
* may either be a dotted mask or a number of bits. Returns 1 if OK,
* otherwise 0.
*/
int acl_parse_ip(const char **text, struct acl_pattern *pattern, int *opaque)
{
struct eb_root *tree = NULL;
if (pattern->flags & ACL_PAT_F_TREE_OK)
tree = pattern->val.tree;
if (str2net(*text, &pattern->val.ipv4.addr, &pattern->val.ipv4.mask)) {
unsigned int mask = ntohl(pattern->val.ipv4.mask.s_addr);
struct ebmb_node *node;
/* check if the mask is contiguous so that we can insert the
* network into the tree. A continuous mask has only ones on
* the left. This means that this mask + its lower bit added
* once again is null.
*/
if (mask + (mask & -mask) == 0 && tree) {
mask = mask ? 33 - flsnz(mask & -mask) : 0; /* equals cidr value */
/* FIXME: insert <addr>/<mask> into the tree here */
node = calloc(1, sizeof(*node) + 4); /* reserve 4 bytes for IPv4 address */
if (!node)
return 0;
memcpy(node->key, &pattern->val.ipv4.addr, 4); /* network byte order */
node->node.pfx = mask;
if (ebmb_insert_prefix(tree, node, 4) != node)
free(node); /* was a duplicate */
pattern->flags |= ACL_PAT_F_TREE;
return 1;
}
return 1;
}
else
return 0;
}
/*
* Registers the ACL keyword list <kwl> as a list of valid keywords for next
* parsing sessions.
*/
void acl_register_keywords(struct acl_kw_list *kwl)
{
LIST_ADDQ(&acl_keywords.list, &kwl->list);
}
/*
* Unregisters the ACL keyword list <kwl> from the list of valid keywords.
*/
void acl_unregister_keywords(struct acl_kw_list *kwl)
{
LIST_DEL(&kwl->list);
LIST_INIT(&kwl->list);
}
/* Return a pointer to the ACL <name> within the list starting at <head>, or
* NULL if not found.
*/
struct acl *find_acl_by_name(const char *name, struct list *head)
{
struct acl *acl;
list_for_each_entry(acl, head, list) {
if (strcmp(acl->name, name) == 0)
return acl;
}
return NULL;
}
/* Return a pointer to the ACL keyword <kw>, or NULL if not found. Note that if
* <kw> contains an opening parenthesis, only the left part of it is checked.
*/
struct acl_keyword *find_acl_kw(const char *kw)
{
int index;
const char *kwend;
struct acl_kw_list *kwl;
kwend = strchr(kw, '(');
if (!kwend)
kwend = kw + strlen(kw);
list_for_each_entry(kwl, &acl_keywords.list, list) {
for (index = 0; kwl->kw[index].kw != NULL; index++) {
if ((strncmp(kwl->kw[index].kw, kw, kwend - kw) == 0) &&
kwl->kw[index].kw[kwend-kw] == 0)
return &kwl->kw[index];
}
}
return NULL;
}
/* NB: does nothing if <pat> is NULL */
static void free_pattern(struct acl_pattern *pat)
{
if (!pat)
return;
if (pat->ptr.ptr) {
if (pat->freeptrbuf)
pat->freeptrbuf(pat->ptr.ptr);
free(pat->ptr.ptr);
}
free(pat);
}
static void free_pattern_list(struct list *head)
{
struct acl_pattern *pat, *tmp;
list_for_each_entry_safe(pat, tmp, head, list)
free_pattern(pat);
}
static void free_pattern_tree(struct eb_root *root)
{
struct eb_node *node, *next;
node = eb_first(root);
while (node) {
next = eb_next(node);
free(node);
node = next;
}
}
static struct acl_expr *prune_acl_expr(struct acl_expr *expr)
{
free_pattern_list(&expr->patterns);
free_pattern_tree(&expr->pattern_tree);
LIST_INIT(&expr->patterns);
if (expr->arg_len && expr->arg.str)
free(expr->arg.str);
expr->kw->use_cnt--;
return expr;
}
static int acl_read_patterns_from_file( struct acl_keyword *aclkw,
struct acl_expr *expr,
const char *filename, int patflags)
{
FILE *file;
char *c;
const char *args[2];
struct acl_pattern *pattern;
int opaque;
int ret = 0;
file = fopen(filename, "r");
if (!file)
return 0;
/* now parse all patterns. The file may contain only one pattern per
* line. If the line contains spaces, they will be part of the pattern.
* The pattern stops at the first CR, LF or EOF encountered.
*/
opaque = 0;
pattern = NULL;
args[1] = "";
while (fgets(trash, sizeof(trash), file) != NULL) {
c = trash;
/* ignore lines beginning with a dash */
if (*c == '#')
continue;
/* strip leading spaces and tabs */
while (*c == ' ' || *c == '\t')
c++;
args[0] = c;
while (*c && *c != '\n' && *c != '\r')
c++;
*c = 0;
/* empty lines are ignored too */
if (c == args[0])
continue;
/* we keep the previous pattern along iterations as long as it's not used */
if (!pattern)
pattern = (struct acl_pattern *)malloc(sizeof(*pattern));
if (!pattern)
goto out_close;
memset(pattern, 0, sizeof(*pattern));
pattern->flags = patflags;
if ((aclkw->requires & ACL_MAY_LOOKUP) && !(pattern->flags & ACL_PAT_F_IGNORE_CASE)) {
/* we pre-set the data pointer to the tree's head so that functions
* which are able to insert in a tree know where to do that.
*/
pattern->flags |= ACL_PAT_F_TREE_OK;
pattern->val.tree = &expr->pattern_tree;
}
if (!aclkw->parse(args, pattern, &opaque))
goto out_free_pattern;
/* if the parser did not feed the tree, let's chain the pattern to the list */
if (!(pattern->flags & ACL_PAT_F_TREE)) {
LIST_ADDQ(&expr->patterns, &pattern->list);
pattern = NULL; /* get a new one */
}
}
ret = 1; /* success */
out_free_pattern:
free_pattern(pattern);
out_close:
fclose(file);
return ret;
}
/* Parse an ACL expression starting at <args>[0], and return it.
* Right now, the only accepted syntax is :
* <subject> [<value>...]
*/
struct acl_expr *parse_acl_expr(const char **args)
{
__label__ out_return, out_free_expr, out_free_pattern;
struct acl_expr *expr;
struct acl_keyword *aclkw;
struct acl_pattern *pattern;
int opaque, patflags;
const char *arg;
aclkw = find_acl_kw(args[0]);
if (!aclkw || !aclkw->parse)
goto out_return;
expr = (struct acl_expr *)calloc(1, sizeof(*expr));
if (!expr)
goto out_return;
expr->kw = aclkw;
aclkw->use_cnt++;
LIST_INIT(&expr->patterns);
expr->pattern_tree = EB_ROOT_UNIQUE;
expr->arg.str = NULL;
expr->arg_len = 0;
arg = strchr(args[0], '(');
if (arg != NULL) {
char *end, *arg2;
/* there is an argument in the form "subject(arg)" */
arg++;
end = strchr(arg, ')');
if (!end)
goto out_free_expr;
arg2 = my_strndup(arg, end - arg);
if (!arg2)
goto out_free_expr;
expr->arg_len = end - arg;
expr->arg.str = arg2;
}
args++;
/* check for options before patterns. Supported options are :
* -i : ignore case for all patterns by default
* -f : read patterns from those files
* -- : everything after this is not an option
*/
patflags = 0;
while (**args == '-') {
if ((*args)[1] == 'i')
patflags |= ACL_PAT_F_IGNORE_CASE;
else if ((*args)[1] == 'f') {
if (!acl_read_patterns_from_file(aclkw, expr, args[1], patflags | ACL_PAT_F_FROM_FILE))
goto out_free_expr;
args++;
}
else if ((*args)[1] == '-') {
args++;
break;
}
else
break;
args++;
}
/* now parse all patterns */
opaque = 0;
while (**args) {
int ret;
pattern = (struct acl_pattern *)calloc(1, sizeof(*pattern));
if (!pattern)
goto out_free_expr;
pattern->flags = patflags;
ret = aclkw->parse(args, pattern, &opaque);
if (!ret)
goto out_free_pattern;
LIST_ADDQ(&expr->patterns, &pattern->list);
args += ret;
}
return expr;
out_free_pattern:
free_pattern(pattern);
out_free_expr:
prune_acl_expr(expr);
free(expr);
out_return:
return NULL;
}
/* Purge everything in the acl <acl>, then return <acl>. */
struct acl *prune_acl(struct acl *acl) {
struct acl_expr *expr, *exprb;
free(acl->name);
list_for_each_entry_safe(expr, exprb, &acl->expr, list) {
LIST_DEL(&expr->list);
prune_acl_expr(expr);
free(expr);
}
return acl;
}
/* Parse an ACL with the name starting at <args>[0], and with a list of already
* known ACLs in <acl>. If the ACL was not in the list, it will be added.
* A pointer to that ACL is returned. If the ACL has an empty name, then it's
* an anonymous one and it won't be merged with any other one.
*
* args syntax: <aclname> <acl_expr>
*/
struct acl *parse_acl(const char **args, struct list *known_acl)
{
__label__ out_return, out_free_acl_expr, out_free_name;
struct acl *cur_acl;
struct acl_expr *acl_expr;
char *name;
if (**args && invalid_char(*args))
goto out_return;
acl_expr = parse_acl_expr(args + 1);
if (!acl_expr)
goto out_return;
/* Check for args beginning with an opening parenthesis just after the
* subject, as this is almost certainly a typo. Right now we can only
* emit a warning, so let's do so.
*/
if (!strchr(args[1], '(') && *args[2] == '(')
Warning("parsing acl '%s' :\n"
" matching '%s' for pattern '%s' is likely a mistake and probably\n"
" not what you want. Maybe you need to remove the extraneous space before '('.\n"
" If you are really sure this is not an error, please insert '--' between the\n"
" match and the pattern to make this warning message disappear.\n",
args[0], args[1], args[2]);
if (*args[0])
cur_acl = find_acl_by_name(args[0], known_acl);
else
cur_acl = NULL;
if (!cur_acl) {
name = strdup(args[0]);
if (!name)
goto out_free_acl_expr;
cur_acl = (struct acl *)calloc(1, sizeof(*cur_acl));
if (cur_acl == NULL)
goto out_free_name;
LIST_INIT(&cur_acl->expr);
LIST_ADDQ(known_acl, &cur_acl->list);
cur_acl->name = name;
}
cur_acl->requires |= acl_expr->kw->requires;
LIST_ADDQ(&cur_acl->expr, &acl_expr->list);
return cur_acl;
out_free_name:
free(name);
out_free_acl_expr:
prune_acl_expr(acl_expr);
free(acl_expr);
out_return:
return NULL;
}
/* Some useful ACLs provided by default. Only those used are allocated. */
const struct {
const char *name;
const char *expr[4]; /* put enough for longest expression */
} default_acl_list[] = {
{ .name = "TRUE", .expr = {"always_true",""}},
{ .name = "FALSE", .expr = {"always_false",""}},
{ .name = "LOCALHOST", .expr = {"src","127.0.0.1/8",""}},
{ .name = "HTTP", .expr = {"req_proto_http",""}},
{ .name = "HTTP_1.0", .expr = {"req_ver","1.0",""}},
{ .name = "HTTP_1.1", .expr = {"req_ver","1.1",""}},
{ .name = "METH_CONNECT", .expr = {"method","CONNECT",""}},
{ .name = "METH_GET", .expr = {"method","GET","HEAD",""}},
{ .name = "METH_HEAD", .expr = {"method","HEAD",""}},
{ .name = "METH_OPTIONS", .expr = {"method","OPTIONS",""}},
{ .name = "METH_POST", .expr = {"method","POST",""}},
{ .name = "METH_TRACE", .expr = {"method","TRACE",""}},
{ .name = "HTTP_URL_ABS", .expr = {"url_reg","^[^/:]*://",""}},
{ .name = "HTTP_URL_SLASH", .expr = {"url_beg","/",""}},
{ .name = "HTTP_URL_STAR", .expr = {"url","*",""}},
{ .name = "HTTP_CONTENT", .expr = {"hdr_val(content-length)","gt","0",""}},
{ .name = "RDP_COOKIE", .expr = {"req_rdp_cookie_cnt","gt","0",""}},
{ .name = "REQ_CONTENT", .expr = {"req_len","gt","0",""}},
{ .name = "WAIT_END", .expr = {"wait_end",""}},
{ .name = NULL, .expr = {""}}
};
/* Find a default ACL from the default_acl list, compile it and return it.
* If the ACL is not found, NULL is returned. In theory, it cannot fail,
* except when default ACLs are broken, in which case it will return NULL.
* If <known_acl> is not NULL, the ACL will be queued at its tail.
*/
struct acl *find_acl_default(const char *acl_name, struct list *known_acl)
{
__label__ out_return, out_free_acl_expr, out_free_name;
struct acl *cur_acl;
struct acl_expr *acl_expr;
char *name;
int index;
for (index = 0; default_acl_list[index].name != NULL; index++) {
if (strcmp(acl_name, default_acl_list[index].name) == 0)
break;
}
if (default_acl_list[index].name == NULL)
return NULL;
acl_expr = parse_acl_expr((const char **)default_acl_list[index].expr);
if (!acl_expr)
goto out_return;
name = strdup(acl_name);
if (!name)
goto out_free_acl_expr;
cur_acl = (struct acl *)calloc(1, sizeof(*cur_acl));
if (cur_acl == NULL)
goto out_free_name;
cur_acl->name = name;
cur_acl->requires |= acl_expr->kw->requires;
LIST_INIT(&cur_acl->expr);
LIST_ADDQ(&cur_acl->expr, &acl_expr->list);
if (known_acl)
LIST_ADDQ(known_acl, &cur_acl->list);
return cur_acl;
out_free_name:
free(name);
out_free_acl_expr:
prune_acl_expr(acl_expr);
free(acl_expr);
out_return:
return NULL;
}
/* Purge everything in the acl_cond <cond>, then return <cond>. */
struct acl_cond *prune_acl_cond(struct acl_cond *cond)
{
struct acl_term_suite *suite, *tmp_suite;
struct acl_term *term, *tmp_term;
/* iterate through all term suites and free all terms and all suites */
list_for_each_entry_safe(suite, tmp_suite, &cond->suites, list) {
list_for_each_entry_safe(term, tmp_term, &suite->terms, list)
free(term);
free(suite);
}
return cond;
}
/* Parse an ACL condition starting at <args>[0], relying on a list of already
* known ACLs passed in <known_acl>. The new condition is returned (or NULL in
* case of low memory). Supports multiple conditions separated by "or".
*/
struct acl_cond *parse_acl_cond(const char **args, struct list *known_acl, int pol)
{
__label__ out_return, out_free_suite, out_free_term;
int arg, neg;
const char *word;
struct acl *cur_acl;
struct acl_term *cur_term;
struct acl_term_suite *cur_suite;
struct acl_cond *cond;
cond = (struct acl_cond *)calloc(1, sizeof(*cond));
if (cond == NULL)
goto out_return;
LIST_INIT(&cond->list);
LIST_INIT(&cond->suites);
cond->pol = pol;
cur_suite = NULL;
neg = 0;
for (arg = 0; *args[arg]; arg++) {
word = args[arg];
/* remove as many exclamation marks as we can */
while (*word == '!') {
neg = !neg;
word++;
}
/* an empty word is allowed because we cannot force the user to
* always think about not leaving exclamation marks alone.
*/
if (!*word)
continue;
if (strcasecmp(word, "or") == 0 || strcmp(word, "||") == 0) {
/* new term suite */
cur_suite = NULL;
neg = 0;
continue;
}
if (strcmp(word, "{") == 0) {
/* we may have a complete ACL expression between two braces,
* find the last one.
*/
int arg_end = arg + 1;
const char **args_new;
while (*args[arg_end] && strcmp(args[arg_end], "}") != 0)
arg_end++;
if (!*args[arg_end])
goto out_free_suite;
args_new = calloc(1, (arg_end - arg + 1) * sizeof(*args_new));
if (!args_new)
goto out_free_suite;
args_new[0] = "";
memcpy(args_new + 1, args + arg + 1, (arg_end - arg) * sizeof(*args_new));
args_new[arg_end - arg] = "";
cur_acl = parse_acl(args_new, known_acl);
free(args_new);
if (!cur_acl)
goto out_free_suite;
arg = arg_end;
}
else {
/* search for <word> in the known ACL names. If we do not find
* it, let's look for it in the default ACLs, and if found, add
* it to the list of ACLs of this proxy. This makes it possible
* to override them.
*/
cur_acl = find_acl_by_name(word, known_acl);
if (cur_acl == NULL) {
cur_acl = find_acl_default(word, known_acl);
if (cur_acl == NULL)
goto out_free_suite;
}
}
cur_term = (struct acl_term *)calloc(1, sizeof(*cur_term));
if (cur_term == NULL)
goto out_free_suite;
cur_term->acl = cur_acl;
cur_term->neg = neg;
cond->requires |= cur_acl->requires;
if (!cur_suite) {
cur_suite = (struct acl_term_suite *)calloc(1, sizeof(*cur_suite));
if (cur_term == NULL)
goto out_free_term;
LIST_INIT(&cur_suite->terms);
LIST_ADDQ(&cond->suites, &cur_suite->list);
}
LIST_ADDQ(&cur_suite->terms, &cur_term->list);
neg = 0;
}
return cond;
out_free_term:
free(cur_term);
out_free_suite:
prune_acl_cond(cond);
free(cond);
out_return:
return NULL;
}
/* Builds an ACL condition starting at the if/unless keyword. The complete
* condition is returned. NULL is returned in case of error or if the first
* word is neither "if" nor "unless". It automatically sets the file name and
* the line number in the condition for better error reporting, and adds the
* ACL requirements to the proxy's acl_requires.
*/
struct acl_cond *build_acl_cond(const char *file, int line, struct proxy *px, const char **args)
{
int pol = ACL_COND_NONE;
struct acl_cond *cond = NULL;
if (!strcmp(*args, "if")) {
pol = ACL_COND_IF;
args++;
}
else if (!strcmp(*args, "unless")) {
pol = ACL_COND_UNLESS;
args++;
}
else
return NULL;
cond = parse_acl_cond(args, &px->acl, pol);
if (!cond)
return NULL;
cond->file = file;
cond->line = line;
px->acl_requires |= cond->requires;
return cond;
}
/* Execute condition <cond> and return either ACL_PAT_FAIL, ACL_PAT_MISS or
* ACL_PAT_PASS depending on the test results. ACL_PAT_MISS may only be
* returned if <dir> contains ACL_PARTIAL, indicating that incomplete data
* is being examined.
* This function only computes the condition, it does not apply the polarity
* required by IF/UNLESS, it's up to the caller to do this using something like
* this :
*
* res = acl_pass(res);
* if (res == ACL_PAT_MISS)
* return 0;
* if (cond->pol == ACL_COND_UNLESS)
* res = !res;
*/
int acl_exec_cond(struct acl_cond *cond, struct proxy *px, struct session *l4, void *l7, int dir)
{
__label__ fetch_next;
struct acl_term_suite *suite;
struct acl_term *term;
struct acl_expr *expr;
struct acl *acl;
struct acl_pattern *pattern;
struct acl_test test;
int acl_res, suite_res, cond_res;
/* We're doing a logical OR between conditions so we initialize to FAIL.
* The MISS status is propagated down from the suites.
*/
cond_res = ACL_PAT_FAIL;
list_for_each_entry(suite, &cond->suites, list) {
/* Evaluate condition suite <suite>. We stop at the first term
* which returns ACL_PAT_FAIL. The MISS status is still propagated
* in case of uncertainty in the result.
*/
/* we're doing a logical AND between terms, so we must set the
* initial value to PASS.
*/
suite_res = ACL_PAT_PASS;
list_for_each_entry(term, &suite->terms, list) {
acl = term->acl;
/* FIXME: use cache !
* check acl->cache_idx for this.
*/
/* ACL result not cached. Let's scan all the expressions
* and use the first one to match.
*/
acl_res = ACL_PAT_FAIL;
list_for_each_entry(expr, &acl->expr, list) {
/* we need to reset context and flags */
memset(&test, 0, sizeof(test));
fetch_next:
if (!expr->kw->fetch(px, l4, l7, dir, expr, &test)) {
/* maybe we could not fetch because of missing data */
if (test.flags & ACL_TEST_F_MAY_CHANGE && dir & ACL_PARTIAL)
acl_res |= ACL_PAT_MISS;
continue;
}
if (test.flags & ACL_TEST_F_RES_SET) {
if (test.flags & ACL_TEST_F_RES_PASS)
acl_res |= ACL_PAT_PASS;
else
acl_res |= ACL_PAT_FAIL;
}
else {
if (!eb_is_empty(&expr->pattern_tree)) {
/* a tree is present, let's check what type it is */
if (expr->kw->match == acl_match_str)
acl_res |= acl_lookup_str(&test, expr) ? ACL_PAT_PASS : ACL_PAT_FAIL;
else if (expr->kw->match == acl_match_ip)
acl_res |= acl_lookup_ip(&test, expr) ? ACL_PAT_PASS : ACL_PAT_FAIL;
}
/* call the match() function for all tests on this value */
list_for_each_entry(pattern, &expr->patterns, list) {
if (acl_res == ACL_PAT_PASS)
break;
acl_res |= expr->kw->match(&test, pattern);
}
if ((test.flags & ACL_TEST_F_NULL_MATCH) &&
LIST_ISEMPTY(&expr->patterns) && eb_is_empty(&expr->pattern_tree))
acl_res |= expr->kw->match(&test, NULL);
}
/*
* OK now acl_res holds the result of this expression
* as one of ACL_PAT_FAIL, ACL_PAT_MISS or ACL_PAT_PASS.
*
* Then if (!MISS) we can cache the result, and put
* (test.flags & ACL_TEST_F_VOLATILE) in the cache flags.
*
* FIXME: implement cache.
*
*/
/* now we may have some cleanup to do */
if (test.flags & ACL_TEST_F_MUST_FREE) {
free(temp_pattern.data.str.str);
temp_pattern.data.str.len = 0;
}
/* we're ORing these terms, so a single PASS is enough */
if (acl_res == ACL_PAT_PASS)
break;
if (test.flags & ACL_TEST_F_FETCH_MORE)
goto fetch_next;
/* sometimes we know the fetched data is subject to change
* later and give another chance for a new match (eg: request
* size, time, ...)
*/
if (test.flags & ACL_TEST_F_MAY_CHANGE && dir & ACL_PARTIAL)
acl_res |= ACL_PAT_MISS;
}
/*
* Here we have the result of an ACL (cached or not).
* ACLs are combined, negated or not, to form conditions.
*/
if (term->neg)
acl_res = acl_neg(acl_res);
suite_res &= acl_res;
/* we're ANDing these terms, so a single FAIL is enough */
if (suite_res == ACL_PAT_FAIL)
break;
}
cond_res |= suite_res;
/* we're ORing these terms, so a single PASS is enough */
if (cond_res == ACL_PAT_PASS)
break;
}
return cond_res;
}
/* Reports a pointer to the first ACL used in condition <cond> which requires
* at least one of the USE_FLAGS in <require>. Returns NULL if none matches.
* The construct is almost the same as for acl_exec_cond() since we're walking
* down the ACL tree as well. It is important that the tree is really walked
* through and never cached, because that way, this function can be used as a
* late check.
*/
struct acl *cond_find_require(const struct acl_cond *cond, unsigned int require)
{
struct acl_term_suite *suite;
struct acl_term *term;
struct acl *acl;
list_for_each_entry(suite, &cond->suites, list) {
list_for_each_entry(term, &suite->terms, list) {
acl = term->acl;
if (acl->requires & require)
return acl;
}
}
return NULL;
}
/*
* Find targets for userlist and groups in acl. Function returns the number
* of errors or OK if everything is fine.
*/
int
acl_find_targets(struct proxy *p)
{
struct acl *acl;
struct acl_expr *expr;
struct acl_pattern *pattern;
struct userlist *ul;
int cfgerr = 0;
list_for_each_entry(acl, &p->acl, list) {
list_for_each_entry(expr, &acl->expr, list) {
if (strcmp(expr->kw->kw, "srv_is_up") == 0 ||
strcmp(expr->kw->kw, "srv_conn") == 0) {
struct proxy *px;
struct server *srv;
char *pname, *sname;
if (!expr->arg.str || !*expr->arg.str) {
Alert("proxy %s: acl %s %s(): missing server name.\n",
p->id, acl->name, expr->kw->kw);
cfgerr++;
continue;
}
pname = expr->arg.str;
sname = strrchr(pname, '/');
if (sname)
*sname++ = '\0';
else {
sname = pname;
pname = NULL;
}
px = p;
if (pname) {
px = findproxy(pname, PR_CAP_BE);
if (!px) {
Alert("proxy %s: acl %s %s(): unable to find proxy '%s'.\n",
p->id, acl->name, expr->kw->kw, pname);
cfgerr++;
continue;
}
}
srv = findserver(px, sname);
if (!srv) {
Alert("proxy %s: acl %s %s(): unable to find server '%s'.\n",
p->id, acl->name, expr->kw->kw, sname);
cfgerr++;
continue;
}
free(expr->arg.str);
expr->arg_len = 0;
expr->arg.srv = srv;
continue;
}
if (strstr(expr->kw->kw, "http_auth") == expr->kw->kw) {
if (!expr->arg.str || !*expr->arg.str) {
Alert("proxy %s: acl %s %s(): missing userlist name.\n",
p->id, acl->name, expr->kw->kw);
cfgerr++;
continue;
}
if (p->uri_auth && p->uri_auth->userlist &&
!strcmp(p->uri_auth->userlist->name, expr->arg.str))
ul = p->uri_auth->userlist;
else
ul = auth_find_userlist(expr->arg.str);
if (!ul) {
Alert("proxy %s: acl %s %s(%s): unable to find userlist.\n",
p->id, acl->name, expr->kw->kw, expr->arg.str);
cfgerr++;
continue;
}
expr->arg_len = 0;
expr->arg.ul = ul;
}
if (!strcmp(expr->kw->kw, "http_auth_group")) {
if (LIST_ISEMPTY(&expr->patterns)) {
Alert("proxy %s: acl %s %s(): no groups specified.\n",
p->id, acl->name, expr->kw->kw);
cfgerr++;
continue;
}
list_for_each_entry(pattern, &expr->patterns, list) {
pattern->val.group_mask = auth_resolve_groups(expr->arg.ul, pattern->ptr.str);
free(pattern->ptr.str);
pattern->ptr.str = NULL;
pattern->len = 0;
if (!pattern->val.group_mask) {
Alert("proxy %s: acl %s %s(): invalid group(s).\n",
p->id, acl->name, expr->kw->kw);
cfgerr++;
continue;
}
}
}
}
}
return cfgerr;
}
/************************************************************************/
/* All supported keywords must be declared here. */
/************************************************************************/
/* Note: must not be declared <const> as its list will be overwritten */
static struct acl_kw_list acl_kws = {{ },{
{ "always_true", acl_parse_nothing, acl_fetch_true, acl_match_nothing, ACL_USE_NOTHING },
{ "always_false", acl_parse_nothing, acl_fetch_false, acl_match_nothing, ACL_USE_NOTHING },
{ "wait_end", acl_parse_nothing, acl_fetch_wait_end, acl_match_nothing, ACL_USE_NOTHING },
{ "req_len", acl_parse_int, acl_fetch_req_len, acl_match_int, ACL_USE_L6REQ_VOLATILE },
{ "req_ssl_hello_type", acl_parse_int, acl_fetch_ssl_hello_type, acl_match_int, ACL_USE_L6REQ_VOLATILE },
{ "rep_ssl_hello_type", acl_parse_int, acl_fetch_ssl_hello_type, acl_match_int, ACL_USE_L6RTR_VOLATILE },
{ "req_ssl_ver", acl_parse_dotted_ver, acl_fetch_req_ssl_ver, acl_match_int, ACL_USE_L6REQ_VOLATILE },
{ "req_rdp_cookie", acl_parse_str, acl_fetch_rdp_cookie, acl_match_str, ACL_USE_L6REQ_VOLATILE|ACL_MAY_LOOKUP },
{ "req_rdp_cookie_cnt", acl_parse_int, acl_fetch_rdp_cookie_cnt, acl_match_int, ACL_USE_L6REQ_VOLATILE },
{ "req_ssl_sni", acl_parse_str, acl_fetch_ssl_hello_sni, acl_match_str, ACL_USE_L6REQ_VOLATILE|ACL_MAY_LOOKUP },
#if 0
{ "time", acl_parse_time, acl_fetch_time, acl_match_time },
#endif
{ NULL, NULL, NULL, NULL }
}};
__attribute__((constructor))
static void __acl_init(void)
{
acl_register_keywords(&acl_kws);
}
/*
* Local variables:
* c-indent-level: 8
* c-basic-offset: 8
* End:
*/