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authorDaniele De Lorenzi <daniele.delorenzi@fastnetserv.net>2019-04-02 15:49:54 +0200
committerGitHub <noreply@github.com>2019-04-02 15:49:54 +0200
commite27022b69886a327205dcdd166d7ccef1d02bcd9 (patch)
tree8e7e1aa15bdff1f152befbe4c6c205e47dcd26e6 /src/lib/protocols/ssl.c
parentc51405e99bae3217545fa34386987b839a8c68a6 (diff)
parent153c77c2cd28d52d6b459263dea3ce988ceccd3c (diff)
Merge pull request #11 from ntop/dev
Add all dev branch modifications
Diffstat (limited to 'src/lib/protocols/ssl.c')
-rw-r--r--src/lib/protocols/ssl.c162
1 files changed, 120 insertions, 42 deletions
diff --git a/src/lib/protocols/ssl.c b/src/lib/protocols/ssl.c
index 25d535a57..05988a8d4 100644
--- a/src/lib/protocols/ssl.c
+++ b/src/lib/protocols/ssl.c
@@ -28,6 +28,7 @@
#include "ndpi_api.h"
// #define CERTIFICATE_DEBUG 1
+
#define NDPI_MAX_SSL_REQUEST_SIZE 10000
/* Skype.c */
@@ -150,9 +151,10 @@ int getSSLcertificate(struct ndpi_detection_module_struct *ndpi_struct,
#ifdef CERTIFICATE_DEBUG
{
- static u_int8_t id = 0;
-
- NDPI_LOG_DBG2(ndpi_struct,"-> [%u] %02X\n", ++id, packet->payload[0] & 0xFF);
+ u_int16_t ssl_version = (packet->payload[1] << 8) + packet->payload[2];
+ u_int16_t ssl_len = (packet->payload[3] << 8) + packet->payload[4];
+
+ printf("SSL Record [version: 0x%02X][len: %u]\n", ssl_version, ssl_len);
}
#endif
@@ -174,10 +176,18 @@ int getSSLcertificate(struct ndpi_detection_module_struct *ndpi_struct,
if(total_len > 4) {
int i;
- if(handshake_protocol == 0x02 || handshake_protocol == 0xb /* Server Hello and Certificate message types are interesting for us */) {
+#ifdef CERTIFICATE_DEBUG
+ printf("SSL [len: %u][handshake_protocol: %02X]\n", packet->payload_packet_len, handshake_protocol);
+#endif
+
+ if((handshake_protocol == 0x02)
+ || (handshake_protocol == 0xb) /* Server Hello and Certificate message types are interesting for us */) {
u_int num_found = 0;
- flow->l4.tcp.ssl_seen_server_cert = 1;
+ if(handshake_protocol == 0x02)
+ flow->l4.tcp.ssl_seen_server_cert = 1;
+ else
+ flow->l4.tcp.ssl_seen_certificate = 1;
/* Check after handshake protocol header (5 bytes) and message header (4 bytes) */
for(i = 9; i < packet->payload_packet_len-3; i++) {
@@ -215,11 +225,11 @@ int getSSLcertificate(struct ndpi_detection_module_struct *ndpi_struct,
break;
} else if(buffer[j] == '.') {
num_dots++;
- if(num_dots >=2) break;
+ if(num_dots >=1) break;
}
}
- if(num_dots >= 2) {
+ if(num_dots >= 1) {
if(!ndpi_struct->disable_metadata_export) {
stripCertificateTrailer(buffer, buffer_len);
snprintf(flow->protos.stun_ssl.ssl.server_certificate,
@@ -232,8 +242,7 @@ int getSSLcertificate(struct ndpi_detection_module_struct *ndpi_struct,
}
} else if(handshake_protocol == 0x01 /* Client Hello */) {
u_int offset, base_offset = 43;
- if (base_offset + 2 <= packet->payload_packet_len)
- {
+ if(base_offset + 2 <= packet->payload_packet_len) {
u_int16_t session_id_len = packet->payload[base_offset];
if((session_id_len+base_offset+2) <= total_len) {
@@ -335,25 +344,94 @@ int getSSLcertificate(struct ndpi_detection_module_struct *ndpi_struct,
return(0); /* Not found */
}
+void getSSLorganization(struct ndpi_detection_module_struct *ndpi_struct,
+ struct ndpi_flow_struct *flow,
+ char *buffer, int buffer_len) {
+ struct ndpi_packet_struct *packet = &flow->packet;
+
+ if(packet->payload[0] != 0x16 /* Handshake */)
+ return;
+
+ u_int16_t total_len = (packet->payload[3] << 8) + packet->payload[4] + 5 /* SSL Header */;
+ u_int8_t handshake_protocol = packet->payload[5]; /* handshake protocol a bit misleading, it is message type according TLS specs */
+
+ if(handshake_protocol != 0x02 && handshake_protocol != 0xb /* Server Hello and Certificate message types are interesting for us */)
+ return;
+
+ /* Truncate total len, search at least in incomplete packet */
+ if(total_len > packet->payload_packet_len)
+ total_len = packet->payload_packet_len;
+
+ memset(buffer, 0, buffer_len);
+
+ /* Check after handshake protocol header (5 bytes) and message header (4 bytes) */
+ u_int num_found = 0;
+ u_int i, j;
+ for(i = 9; i < packet->payload_packet_len-4; i++) {
+ /* Organization OID: 2.5.4.10 */
+ if((packet->payload[i] == 0x55) && (packet->payload[i+1] == 0x04) && (packet->payload[i+2] == 0x0a)) {
+ u_int8_t type_tag = packet->payload[i+3]; // 0x0c: utf8string / 0x13: printable_string
+ u_int8_t server_len = packet->payload[i+4];
+
+ num_found++;
+ /* what we want is subject certificate, so we bypass the issuer certificate */
+ if(num_found != 2) continue;
+
+ // packet is truncated... further inspection is not needed
+ if(i+4+server_len >= packet->payload_packet_len) {
+ break;
+ }
+
+ char *server_org = (char*)&packet->payload[i+5];
+
+ u_int len = (u_int)ndpi_min(server_len, buffer_len-1);
+ strncpy(buffer, server_org, len);
+ buffer[len] = '\0';
+
+ // check if organization string are all printable
+ u_int8_t is_printable = 1;
+ for (j = 0; j < len; j++) {
+ if(!ndpi_isprint(buffer[j])) {
+ is_printable = 0;
+ break;
+ }
+ }
+
+ if(is_printable == 1) {
+ snprintf(flow->protos.stun_ssl.ssl.server_organization,
+ sizeof(flow->protos.stun_ssl.ssl.server_organization), "%s", buffer);
+#ifdef CERTIFICATE_DEBUG
+ printf("Certificate origanization: %s\n", flow->protos.stun_ssl.ssl.server_organization);
+#endif
+ }
+ }
+ }
+}
+
int sslTryAndRetrieveServerCertificate(struct ndpi_detection_module_struct *ndpi_struct, struct ndpi_flow_struct *flow) {
struct ndpi_packet_struct *packet = &flow->packet;
/* consider only specific SSL packets (handshake) */
if((packet->payload_packet_len > 9) && (packet->payload[0] == 0x16)) {
char certificate[64];
+ char organization[64];
int rc;
certificate[0] = '\0';
rc = getSSLcertificate(ndpi_struct, flow, certificate, sizeof(certificate));
packet->ssl_certificate_num_checks++;
- if (rc > 0) {
+ if(rc > 0) {
+ // try fetch server organization once server certificate is found
+ organization[0] = '\0';
+ getSSLorganization(ndpi_struct, flow, organization, sizeof(organization));
+
packet->ssl_certificate_detected++;
- if ((flow->l4.tcp.ssl_seen_server_cert == 1) && (flow->protos.stun_ssl.ssl.server_certificate[0] != '\0'))
+ if((flow->l4.tcp.ssl_seen_server_cert == 1) && (flow->protos.stun_ssl.ssl.server_certificate[0] != '\0'))
/* 0 means we're done processing extra packets (since we found what we wanted) */
return 0;
}
/* Client hello, Server Hello, and certificate packets probably all checked in this case */
- if ((packet->ssl_certificate_num_checks >= 3)
+ if((packet->ssl_certificate_num_checks >= 3)
&& (flow->l4.tcp.seen_syn)
&& (flow->l4.tcp.seen_syn_ack)
&& (flow->l4.tcp.seen_ack) /* We have seen the 3-way handshake */)
@@ -369,7 +447,7 @@ int sslTryAndRetrieveServerCertificate(struct ndpi_detection_module_struct *ndpi
void sslInitExtraPacketProcessing(int caseNum, struct ndpi_flow_struct *flow) {
flow->check_extra_packets = 1;
/* 0 is the case for waiting for the server certificate */
- if (caseNum == 0) {
+ if(caseNum == 0) {
/* At most 7 packets should almost always be enough to find the server certificate if it's there */
flow->max_extra_packets_to_check = 7;
flow->extra_packets_func = sslTryAndRetrieveServerCertificate;
@@ -405,7 +483,8 @@ int sslDetectProtocolFromCertificate(struct ndpi_detection_module_struct *ndpi_s
/* If we've detected the subprotocol from client certificate but haven't had a chance
* to see the server certificate yet, set up extra packet processing to wait
* a few more packets. */
- if(((flow->l4.tcp.ssl_seen_client_cert == 1) && (flow->protos.stun_ssl.ssl.client_certificate[0] != '\0')) && ((flow->l4.tcp.ssl_seen_server_cert != 1) && (flow->protos.stun_ssl.ssl.server_certificate[0] == '\0'))) {
+ if(((flow->l4.tcp.ssl_seen_client_cert == 1) && (flow->protos.stun_ssl.ssl.client_certificate[0] != '\0'))
+ && ((flow->l4.tcp.ssl_seen_server_cert != 1) && (flow->protos.stun_ssl.ssl.server_certificate[0] == '\0'))) {
sslInitExtraPacketProcessing(0, flow);
}
@@ -418,11 +497,13 @@ int sslDetectProtocolFromCertificate(struct ndpi_detection_module_struct *ndpi_s
return(rc);
}
- if(((packet->ssl_certificate_num_checks >= 2)
+ if(((packet->ssl_certificate_num_checks >= 3)
&& flow->l4.tcp.seen_syn
&& flow->l4.tcp.seen_syn_ack
&& flow->l4.tcp.seen_ack /* We have seen the 3-way handshake */)
- || ((flow->l4.tcp.ssl_seen_server_cert == 1) && (flow->protos.stun_ssl.ssl.server_certificate[0] != '\0'))
+ || ((flow->l4.tcp.ssl_seen_certificate == 1)
+ && (flow->l4.tcp.ssl_seen_server_cert == 1)
+ && (flow->protos.stun_ssl.ssl.server_certificate[0] != '\0'))
/* || ((flow->l4.tcp.ssl_seen_client_cert == 1) && (flow->protos.stun_ssl.ssl.client_certificate[0] != '\0')) */
) {
ndpi_int_ssl_add_connection(ndpi_struct, flow, NDPI_PROTOCOL_SSL);
@@ -432,8 +513,7 @@ int sslDetectProtocolFromCertificate(struct ndpi_detection_module_struct *ndpi_s
return(0);
}
-static void ssl_mark_and_payload_search_for_other_protocols(struct
- ndpi_detection_module_struct
+static void ssl_mark_and_payload_search_for_other_protocols(struct ndpi_detection_module_struct
*ndpi_struct, struct ndpi_flow_struct *flow)
{
struct ndpi_packet_struct *packet = &flow->packet;
@@ -510,16 +590,16 @@ static void ssl_mark_and_payload_search_for_other_protocols(struct
/* SSL without certificate (Skype, Ultrasurf?) */
NDPI_LOG_INFO(ndpi_struct, "found ssl NO_CERT\n");
ndpi_int_ssl_add_connection(ndpi_struct, flow, NDPI_PROTOCOL_SSL_NO_CERT);
- } else
+ } else if(packet->ssl_certificate_num_checks >= 3) {
NDPI_LOG_INFO(ndpi_struct, "found ssl\n");
- ndpi_int_ssl_add_connection(ndpi_struct, flow, NDPI_PROTOCOL_SSL);
+ ndpi_int_ssl_add_connection(ndpi_struct, flow, NDPI_PROTOCOL_SSL);
+ }
}
}
static u_int8_t ndpi_search_sslv3_direction1(struct ndpi_detection_module_struct *ndpi_struct,
struct ndpi_flow_struct *flow) {
-
struct ndpi_packet_struct *packet = &flow->packet;
if((packet->payload_packet_len >= 5)
@@ -559,7 +639,7 @@ static u_int8_t ndpi_search_sslv3_direction1(struct ndpi_detection_module_struct
}
}
- if((packet->payload_packet_len > temp && packet->payload_packet_len > 100) && packet->payload_packet_len > 9) {
+ if((packet->payload_packet_len > temp) && (packet->payload_packet_len > 100)) {
/* the server hello may be split into small packets and the certificate has its own SSL Record
* so temp contains only the length for the first ServerHello block */
u_int32_t cert_start;
@@ -647,27 +727,25 @@ void ndpi_search_ssl_tcp(struct ndpi_detection_module_struct *ndpi_struct, struc
NDPI_LOG_DBG(ndpi_struct, "search ssl\n");
- {
- /* Check if this is whatsapp first (this proto runs over port 443) */
- if((packet->payload_packet_len > 5)
- && ((packet->payload[0] == 'W')
- && (packet->payload[1] == 'A')
- && (packet->payload[4] == 0)
- && (packet->payload[2] <= 9)
- && (packet->payload[3] <= 9))) {
- ndpi_set_detected_protocol(ndpi_struct, flow, NDPI_PROTOCOL_WHATSAPP, NDPI_PROTOCOL_UNKNOWN);
- return;
- } else if((packet->payload_packet_len == 4)
- && (packet->payload[0] == 'W')
- && (packet->payload[1] == 'A')) {
- ndpi_set_detected_protocol(ndpi_struct, flow, NDPI_PROTOCOL_WHATSAPP, NDPI_PROTOCOL_UNKNOWN);
+ /* Check if this is whatsapp first (this proto runs over port 443) */
+ if((packet->payload_packet_len > 5)
+ && ((packet->payload[0] == 'W')
+ && (packet->payload[1] == 'A')
+ && (packet->payload[4] == 0)
+ && (packet->payload[2] <= 9)
+ && (packet->payload[3] <= 9))) {
+ ndpi_set_detected_protocol(ndpi_struct, flow, NDPI_PROTOCOL_WHATSAPP, NDPI_PROTOCOL_UNKNOWN);
+ return;
+ } else if((packet->payload_packet_len == 4)
+ && (packet->payload[0] == 'W')
+ && (packet->payload[1] == 'A')) {
+ ndpi_set_detected_protocol(ndpi_struct, flow, NDPI_PROTOCOL_WHATSAPP, NDPI_PROTOCOL_UNKNOWN);
+ return;
+ } else {
+ /* No whatsapp, let's try SSL */
+ if(sslDetectProtocolFromCertificate(ndpi_struct, flow) > 0)
return;
- } else {
- /* No whatsapp, let's try SSL */
- if(sslDetectProtocolFromCertificate(ndpi_struct, flow) > 0)
- return;
- }
- }
+ }
if(packet->payload_packet_len > 40 && flow->l4.tcp.ssl_stage == 0) {
NDPI_LOG_DBG2(ndpi_struct, "first ssl packet\n");