unsigned
asn1_integer(struct NetFrame *frame, const unsigned char *px, unsigned length, unsigned *r_offset)
{
unsigned int_length;
unsigned result;
unsigned tag;
tag = px[(*r_offset)++];
if (tag != 0x0a && tag != 0x02 && tag != 0x01)
FRAMERR_BADVAL(frame, "asn1", tag);
int_length = asn1_length(frame, px, length, r_offset);
if (int_length == 0xFFFFffff) {
*r_offset = length;
return 0xFFFFffff;
}
if (*r_offset + int_length > length) {
FRAMERR(frame, "snmp: truncated\n");
*r_offset = length;
return 0xFFFFffff;
}
result = 0;
while (int_length--)
result = result * 256 + px[(*r_offset)++];
return result;
}
static void process_ldap_filter(struct NetFrame *frame, const unsigned char *px, unsigned length, unsigned *r_offset, struct FILTER **r_filter)
{
unsigned len;
struct FILTER *filter;
*r_filter = (struct FILTER*)malloc(sizeof(struct FILTER));
memset(*r_filter, 0, sizeof(struct FILTER));
filter = *r_filter;
filter->tag = asn1_tag(px,length,r_offset);
len = asn1_length(frame,px,length,r_offset);
if (length > *r_offset+len)
length = *r_offset+len;
switch (filter->tag) {
case 0xa0: /* 'and' - SET OF Filter */
case 0xa1: /* 'or' - SET OF Filter */
while (*r_offset < length) {
if (filter->count < 128) {
process_ldap_filter(frame, px, length, r_offset, &filter->data.filters[filter->count++]);
} else {
asn1_tag(px,length,r_offset);
len = asn1_length(frame,px,length,r_offset);
*r_offset += len;
}
}
break;
case 0xa3: /*equalityMatch - AttributeValueAssertion */
case 0xa5: /*greaterOrEqual - AttributeValueAssertion */
case 0xa6: /*lessOrEqual - AttributeValueAssertion */
asn1_string(frame, px, length, r_offset, &filter->data.val.attributeDescription, &filter->data.val.attributeDescription_length);
asn1_string(frame, px, length, r_offset, &filter->data.val.assertionValue, &filter->data.val.assertionValue_length);
break;
case 0xa4: /*substrings - SubstringFilter */
case 0xa7: /*present - AttributeDescription */
case 0xa8: /*approxMatch - AttributeValueAssertion, default */
default:
FRAMERR_BADVAL(frame, "ldap", filter->tag);
break;
}
*r_offset = length;
}
void process_ldap(struct Ferret *ferret, struct NetFrame *frame, const unsigned char *px, unsigned length)
{
unsigned offset=0;
unsigned outer_length;
struct LDAP ldap[1];
if (ferret)
return;
memset(ldap, 0, sizeof(ldap[0]));
/* tag */
if (asn1_tag(px, length, &offset) != 0x30)
return;
/* length */
outer_length = asn1_length(frame, px, length, &offset);
if (length > outer_length + offset)
length = outer_length + offset;
/* Version */
ldap->message_id = asn1_integer(frame, px, length, &offset);
/* PDU */
ldap->message_type = asn1_tag(px, length, &offset);
outer_length = asn1_length(frame, px, length, &offset);
if (length > outer_length + offset)
length = outer_length + offset;
switch (ldap->message_type) {
case 0x63:
process_ldap_search_request(ferret, frame, px+offset, length-offset, ldap);
break;
default:
FRAMERR_BADVAL(frame, "ldap", ldap->message_type);
break;
}
}
void
asn1_string(struct NetFrame *frame, const unsigned char *px, unsigned length, unsigned *r_offset, const unsigned char **r_str, unsigned *r_str_length)
{
unsigned len;
unsigned tag;
if (*r_offset >= length)
return;
tag = asn1_tag(px, length, r_offset);
len = asn1_length(frame, px, length, r_offset);
*r_str = px + *r_offset;
*r_str_length = len;
*r_offset += len;
}
void
asn1_string(struct NetFrame *frame, const unsigned char *px, unsigned length, unsigned *r_offset, const unsigned char **r_str, unsigned *r_str_length)
{
unsigned len;
//unsigned tag;
if (*r_offset >= length)
return;
/* [tag] */
asn1_tag(px, length, r_offset);
/* [length] */
len = asn1_length(frame, px, length, r_offset);
/* [value] */
*r_str = px + *r_offset;
*r_str_length = len;
*r_offset += len;
}
/**
* This code analyzes a <name=value> pair within a cookie, within the
* context of an HTTP request, which includes relavent information
* about the host that it comes from
*/
void parse_http_cookie(struct TCPRECORD *sess, struct NetFrame *frame, const unsigned char *name, unsigned name_length, const unsigned char *value, unsigned value_length)
{
struct HTTPREQUEST *req = &sess->layer7.httpreq;
unsigned char *dec;
unsigned dec_length = value_length;
if (dec_length > 1000)
dec_length = 1000;
switch (toupper(name[0])) {
case 'C':
/* MYSPACE COUNTRY CODE
* Example:
* COUNTRYCODE=MFMGCisGAQQBgjdYA%2FmgRTBDBgorBgEEAYI3WAMBoDUwMwIDAgABAgJmAwICAMAECOOUmLvDDv%2BRBBB6gRxsNuYMZ2M7SXM7N4fdBAgyFGPRkgkD7Q%3D%3D;
*/
if (match_name("COUNTRYCODE", name, name_length) && ends_with_t(".myspace.com", req->host)) {
unsigned char *dec0;
unsigned dec0_length;
unsigned i;
/* First, "uudecode" this */
dec0 = alloca(value_length);
dec0_length = 0;
for (i=0; i<value_length; i++) {
if (value[i] != '%')
dec0[dec0_length++] = value[i];
else {
unsigned c=0;
i++;
if (i<value_length && isxdigit(value[i]))
c = hexval(value[i++])<<4;
if (i<value_length && isxdigit(value[i]))
c |= hexval(value[i++]);
dec0[dec0_length++] = (unsigned char)c;
i--;
}
}
/* Second, "base64 decode" this */
dec = alloca(dec0_length);
dec_length = base64_decode(dec, dec_length, value, value_length);
/* Third, "asn.1 decode" this */
{
unsigned tag, len;
const unsigned char *px = dec;
unsigned offset = 0;
unsigned length = dec_length;
unsigned max_offset;
tag = asn1_tag(px,length,&offset);
len = asn1_length(frame,px,length, &offset);
/* Process the big object */
if (tag == 0x30 && len != 0xFFFFFFFF) {
max_offset = offset+len;
tag = asn1_tag(px,max_offset,&offset);
len = asn1_length(frame,px,max_offset, &offset);
/* Process the OID */
if (tag == 0x06) {
JOTDOWN(sess->eng->ferret,
JOT_SRC("ID-IP", frame),
JOT_OID("MySpace-CountryCode", px+offset, len),
0);
}
offset += len;
}
}
}
break;
case 'D':
/*
go.com (including such properties as espn.com) put in their cookies
some sort of location information. Here are some examples that were googled
from the web:
Z2JyO2VuZztsb25kb247YnJvYWRiYW5kOzU7NTs0Oy0xOzA1MS41MDA7LTAwMC4xMTc7ODI2OzEwMTk4OzQ3ODI7NTsK
Z2JyO2VuZztsb25kb247YnJvYWRiYW5kOzU7NTs1Oy0xOzA1MS41MDA7LTAwMC4xMTc7ODI2OzEwMTk4OzQ3ODI7NTsK
dXNhO21kO2NvbGxlZ2UgcGFyazt0MTs1OzQ7NDs1MTE7MDM4Ljk5NzstMDc2LjkyODs4NDA7MjE7MTU7NjsK
dXNhO3R4O2RhbGxhczticm9hZGJhbmQ7NTs0OzQ7NjIzOzAzMi43ODc7LTA5Ni43OTk7ODQwOzQ0Ozc3OzY7Cg==
dXNhO3R4O2RhbGxhczticm9hZGJhbmQ7NTs0OzQ7NjIzOzAzMi43ODc7LTA5Ni43OTk7ODQwOzQ0Ozc3OzY7Cg==
dXNhO2dhO2F0bGFudGE7YnJvYWRiYW5kOzU7NTs1OzUyNDswMzMuNzQ5Oy0wODQuMzg4Ozg0MDsxMTszOzY7Cg==
dXNhO29yO2JlYXZlcnRvbjticm9hZGJhbmQ7NTszOzM7ODIwOzA0NS40OTE7LTEyMi44MDU7ODQwOzM4OzYyOzY7Cg==
dXNhO3R4O2RhbGxhczticm9hZGJhbmQ7NTs0OzQ7NjIzOzAzMi43ODc7LTA5Ni43OTk7ODQwOzQ0Ozc3OzY7Cg==
dXNhO3R4O2RhbGxhczticm9hZGJhbmQ7NTs0OzM7NjIzOzAzMi43ODc7LTA5Ni43OTk7ODQwOzQ0Ozc3OzY7Cg==
*/
if (match_name("DE2", name, name_length) && ends_with_t(".go.com", req->host)) {
dec = alloca(dec_length);
dec_length = base64_decode(dec, dec_length, value, value_length);
JOTDOWN(sess->eng->ferret,
JOT_SRC("ID-IP", frame),
JOT_PRINT("GO-LOC", dec, dec_length),
0);
}
break;
case 'E':
if (starts_with("EMAIL", name, name_length)) {
JOTDOWN(sess->eng->ferret,
JOT_SRC("ID-IP", frame),
JOT_PRINT("e-mail", value, value_length),
0);
}
if (starts_with("E-MAIL", name, name_length)) {
JOTDOWN(sess->eng->ferret,
JOT_SRC("ID-IP", frame),
JOT_PRINT("e-mail", value, value_length),
0);
}
break;
case 'G':
/*
d78da8e7eb998e8f571c4c641b104c60cxsAAABVUyxnYSxsYXdyZW5jZXZpbGxlLCwsLCw1MjQ=
bf8e3d7c0474fa9da14b6551e6846ec7cxUAAABVUyxnYSxhdGxhbnRhLCwsLCw1MjQ=
*/
if (match_name("GEO", name, name_length) && ends_with_t(".youtube.com", req->host)) {
unsigned i;
unsigned comma_count=0;
dec = alloca(dec_length);
dec_length = base64_decode(dec, dec_length, value, value_length);
for (i=dec_length; i>0; i--) {
if (dec[i-1] == ',') {
/*US,ga,lawrenceville,,,,,524*/
if (++comma_count == 7)
break;
}
}
if (i>3 && isalpha(dec[i-2]) && isalpha(dec[i-3])) {
unsigned offset=i-3;
while (i<dec_length && comma_count > 5) {
if (dec[i] == ',')
comma_count--;
i++;
}
JOTDOWN(sess->eng->ferret,
JOT_SRC("ID-IP", frame),
JOT_PRINT("YouTube-Loc", dec+offset, i-offset-1),
0);
}
}
/*Example:
* [email protected]/769779
*/
if (match_name("GMAILCHAT", name, name_length) && ends_with_t("mail.google.com", req->host)) {
unsigned j;
for (j=0; j<value_length && value[j] != '/'; j++)
;
JOTDOWN(sess->eng->ferret,
JOT_SRC("ID-IP", frame),
JOT_PRINT("e-mail", value, j),
0);
}
break;
case 'I':
if (match_name("ID", name, name_length) && ends_with_t(".doubleclick.net", req->host)) {
JOTDOWN(sess->eng->ferret,
JOT_SRC("ID-IP", frame),
JOT_PRINT("DoubleClick", value, value_length),
0);
}
break;
case 'L':
if (match_name("LOGIN", name, name_length) || match_name("LOGIN_X", name, name_length)) {
JOTDOWN(sess->eng->ferret,
JOT_SRC("ID-IP", frame),
JOT_URLENC("login", value, value_length),
0);
if (ends_with_t(".facebook.com", req->host)) {
req->login = stringtab_lookup(sess->eng->stringtab, value, value_length);
JOTDOWN(sess->eng->ferret,
JOT_SRC("ID-IP", frame),
JOT_URLENC("Facebook-user", req->login->str, req->login->length),
0);
}
if (contains("@", value, value_length)) {
JOTDOWN(sess->eng->ferret,
JOT_SRC("ID-IP", frame),
JOT_URLENC("e-mail", value, value_length),
0);
} else if (contains("%40", value, value_length)) {
JOTDOWN(sess->eng->ferret,
JOT_SRC("ID-IP", frame),
JOT_URLENC("e-mail", value, value_length),
0);
}
}
break;
case 'M':
/*http://facebook.com
*m_user = warnerc2%40gpc.edu%3A71101757%3ASwUchOEuvzIbYo7E*/
if (match_name("M_USER", name, name_length)) {
if (ends_with_t(".facebook.com", req->host)) {
JOTDOWN(sess->eng->ferret,
JOT_SRC("ID-IP", frame),
JOT_URLENC("e-mail", value, value_length),
0);
}
}
/* http://login.live.com/login.srf
* [email protected] */
if (match_name("MSPPRE", name, name_length)) {
if (ends_with_t(".live.com", req->host)) {
JOTDOWN(sess->eng->ferret,
JOT_SRC("ID-IP", frame),
JOT_PRINT("e-mail", value, value_length),
0);
}
}
/* Canadian Broadcasting */
if (match_name("MyCBCSignIn", name, name_length)) {
if (ends_with_t(".cbc.ca", req->host)) {
JOTDOWN(sess->eng->ferret,
JOT_SRC("ID-IP", frame),
JOT_PRINT("e-mail", value, value_length),
0);
}
}
if (match_name("ME", name, name_length)) {
if (ends_with_t(".myspace.com", req->host)) {
JOTDOWN(sess->eng->ferret,
JOT_SRC("ID-IP", frame),
JOT_URLENC("e-mail", value, value_length),
0);
}
}
break;
case 'P':
if (starts_with("PASSWORD", name, name_length)) {
JOTDOWN(sess->eng->ferret,
JOT_SRC("ID-IP", frame),
JOT_PRINT("password", value, value_length),
0);
}
break;
case 'U':
if (starts_with("USERNAME", name, name_length)) {
JOTDOWN(sess->eng->ferret,
JOT_SRC("ID-IP", frame),
JOT_PRINT("username", value, value_length),
0);
}
break;
case 'W':
if (starts_with("WATCHED_VIDEO_ID_LIST_", name, name_length)) {
size_t l = sizeof("WATCHED_VIDEO_ID_LIST_")-1;
JOTDOWN(sess->eng->ferret,
JOT_SRC("ID-IP", frame),
JOT_URLENC("YouTube-ID", name+l, name_length-l),
0);
}
break;
}
}
END_TEST
/*******************************************************************************
* length
*/
START_TEST(test_asn1_length)
{
chunk_t a;
a = chunk_empty;
ck_assert(asn1_length(&a) == ASN1_INVALID_LENGTH);
a = chunk_from_chars(0x04);
ck_assert(asn1_length(&a) == ASN1_INVALID_LENGTH);
a = chunk_from_chars(0x04, 0x00);
ck_assert(asn1_length(&a) == 0);
a = chunk_from_chars(0x04, 0x01);
ck_assert(asn1_length(&a) == ASN1_INVALID_LENGTH);
a = chunk_from_chars(0x04, 0x01, 0xaa);
ck_assert(asn1_length(&a) == 1);
a = chunk_from_chars(0x04, 0x7f, 0xaa);
a.len = 2 + 127;
ck_assert(asn1_length(&a) == 127);
a = chunk_from_chars(0x04, 0x80, 0xaa);
a.len = 2 + 128;
ck_assert(asn1_length(&a) == ASN1_INVALID_LENGTH);
a = chunk_from_chars(0x04, 0x81);
ck_assert(asn1_length(&a) == ASN1_INVALID_LENGTH);
a = chunk_from_chars(0x04, 0x81, 0x00);
ck_assert(asn1_length(&a) == 0);
a = chunk_from_chars(0x04, 0x81, 0x80, 0xaa);
ck_assert(asn1_length(&a) == ASN1_INVALID_LENGTH);
a = chunk_from_chars(0x04, 0x81, 0x80, 0xaa);
a.len = 3 + 128;
ck_assert(asn1_length(&a) == 128);
a = chunk_from_chars(0x04, 0x82, 0x01, 0x02, 0xaa);
a.len = 4 + 258;
ck_assert(asn1_length(&a) == 258);
a = chunk_from_chars(0x04, 0x83, 0x01, 0x02, 0x03, 0xaa);
a.len = 5 + 66051;
ck_assert(asn1_length(&a) == 66051);
a = chunk_from_chars(0x04, 0x84, 0x01, 0x02, 0x03, 0x04, 0xaa);
a.len = 6 + 16909060;
ck_assert(asn1_length(&a) == 16909060);
/* largest chunk on 32 bit system */
a = chunk_from_chars(0x04, 0x84, 0xff, 0xff, 0xff, 0xf9, 0xaa);
a.len = 4294967295;
ck_assert(asn1_length(&a) == 4294967289);
}
END_TEST
/*******************************************************************************
* length
*/
START_TEST(test_asn1_length)
{
chunk_t a;
a = chunk_empty;
ck_assert(asn1_length(&a) == ASN1_INVALID_LENGTH);
a = chunk_from_chars(0x04);
ck_assert(asn1_length(&a) == ASN1_INVALID_LENGTH);
a = chunk_from_chars(0x04, 0x00);
ck_assert(asn1_length(&a) == 0);
a = chunk_from_chars(0x04, 0x01);
ck_assert(asn1_length(&a) == ASN1_INVALID_LENGTH);
a = chunk_from_chars(0x04, 0x01, 0xaa);
ck_assert(asn1_length(&a) == 1);
a = chunk_from_chars(0x04, 0x7f, 0xaa);
a.len = 2 + 127;
ck_assert(asn1_length(&a) == 127);
a = chunk_from_chars(0x04, 0x80, 0xaa);
a.len = 2 + 128;
ck_assert(asn1_length(&a) == ASN1_INVALID_LENGTH);
a = chunk_from_chars(0x04, 0x81);
ck_assert(asn1_length(&a) == ASN1_INVALID_LENGTH);
a = chunk_from_chars(0x04, 0x81, 0x80, 0xaa);
ck_assert(asn1_length(&a) == ASN1_INVALID_LENGTH);
a = chunk_from_chars(0x04, 0x81, 0x80, 0xaa);
a.len = 3 + 128;
ck_assert(asn1_length(&a) == 128);
a = chunk_from_chars(0x04, 0x82, 0x01, 0x02, 0xaa);
a.len = 4 + 258;
ck_assert(asn1_length(&a) == 258);
a = chunk_from_chars(0x04, 0x83, 0x01, 0x02, 0x03, 0xaa);
a.len = 5 + 66051;
ck_assert(asn1_length(&a) == 66051);
}
