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-rw-r--r--release/src/router/cyassl/src/sniffer.c2187
1 files changed, 2187 insertions, 0 deletions
diff --git a/release/src/router/cyassl/src/sniffer.c b/release/src/router/cyassl/src/sniffer.c
new file mode 100644
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+/* sniffer.c
+ *
+ * Copyright (C) 2006-2011 Sawtooth Consulting Ltd.
+ *
+ * This file is part of CyaSSL.
+ *
+ * CyaSSL 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.
+ *
+ * CyaSSL is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA
+ */
+
+#ifdef CYASSL_SNIFFER
+
+#include "ssl.h"
+#include "cyassl_int.h"
+#include "cyassl_error.h"
+#include "sniffer.h"
+#include "sniffer_error.h"
+#include <time.h>
+
+#ifndef _WIN32
+ #include <arpa/inet.h>
+#endif
+
+#include <assert.h>
+
+
+#ifdef _WIN32
+ #define SNPRINTF _snprintf
+#else
+ #define SNPRINTF snprintf
+#endif
+
+
+/* Misc constants */
+enum {
+ MAX_SERVER_ADDRESS = 128, /* maximum server address length */
+ MAX_ERROR_LEN = 80, /* maximum error length */
+ ETHER_IF_ADDR_LEN = 6, /* ethernet interface address length */
+ LOCAL_IF_ADDR_LEN = 4, /* localhost interface address length, !windows */
+ TCP_PROTO = 6, /* TCP_PROTOCOL */
+ IP_HDR_SZ = 20, /* IP header legnth, min */
+ TCP_HDR_SZ = 20, /* TCP header legnth, min */
+ IPV4 = 4, /* IP version 4 */
+ TCP_PROTOCOL = 6, /* TCP Protocol id */
+ TRACE_MSG_SZ = 80, /* Trace Message buffer size */
+ HASH_SIZE = 499, /* Session Hash Table Rows */
+ PSEUDO_HDR_SZ = 12, /* TCP Pseudo Header size in bytes */
+ FATAL_ERROR_STATE = 1, /* SnifferSession fatal error state */
+ SNIFFER_TIMEOUT = 900, /* Cache unclosed Sessions for 15 minutes */
+};
+
+
+#ifdef _WIN32
+
+static HMODULE dllModule; /* for error string resources */
+
+BOOL APIENTRY DllMain( HMODULE hModule,
+ DWORD ul_reason_for_call,
+ LPVOID lpReserved
+ )
+{
+ static int didInit = 0;
+
+ switch (ul_reason_for_call)
+ {
+ case DLL_PROCESS_ATTACH:
+ if (didInit == 0) {
+ dllModule = hModule;
+ ssl_InitSniffer();
+ didInit = 1;
+ }
+ break;
+ case DLL_THREAD_ATTACH:
+ break;
+ case DLL_THREAD_DETACH:
+ break;
+ case DLL_PROCESS_DETACH:
+ if (didInit) {
+ ssl_FreeSniffer();
+ didInit = 0;
+ }
+ break;
+ }
+ return TRUE;
+}
+
+#endif /* _WIN32 */
+
+
+static int TraceOn = 0; /* Trace is off by default */
+static FILE* TraceFile = 0;
+
+
+/* windows uses .rc talbe for this */
+#ifndef _WIN32
+
+static const char* const msgTable[] =
+{
+ /* 1 */
+ "Out of Memory",
+ "New SSL Sniffer Server Registered",
+ "Checking IP Header",
+ "SSL Sniffer Server Not Registered",
+ "Checking TCP Header",
+
+ /* 6 */
+ "SSL Sniffer Server Port Not Registered",
+ "RSA Private Decrypt Error",
+ "RSA Private Decode Error",
+ "Set Cipher Spec Error",
+ "Server Hello Input Malformed",
+
+ /* 11 */
+ "Couldn't Resume Session Error",
+ "Server Did Resumption",
+ "Client Hello Input Malformed",
+ "Client Trying to Resume",
+ "Handshake Input Malformed",
+
+ /* 16 */
+ "Got Hello Verify msg",
+ "Got Server Hello msg",
+ "Got Cert Request msg",
+ "Got Server Key Exchange msg",
+ "Got Cert msg",
+
+ /* 21 */
+ "Got Server Hello Done msg",
+ "Got Finished msg",
+ "Got Client Hello msg",
+ "Got Client Key Exchange msg",
+ "Got Cert Verify msg",
+
+ /* 26 */
+ "Got Unknown Handshake msg",
+ "New SSL Sniffer Session created",
+ "Couldn't create new SSL",
+ "Got a Packet to decode",
+ "No data present",
+
+ /* 31 */
+ "Session Not Found",
+ "Got an Old Client Hello msg",
+ "Old Client Hello Input Malformed",
+ "Old Client Hello OK",
+ "Bad Old Client Hello",
+
+ /* 36 */
+ "Bad Record Header",
+ "Record Header Input Malformed",
+ "Got a HandShake msg",
+ "Bad HandShake msg",
+ "Got a Change Cipher Spec msg",
+
+ /* 41 */
+ "Got Application Data msg",
+ "Bad Application Data",
+ "Got an Alert msg",
+ "Another msg to Process",
+ "Removing Session From Table",
+
+ /* 46 */
+ "Bad Key File",
+ "Wrong IP Version",
+ "Wrong Protocol type",
+ "Packet Short for header processing",
+ "Got Unknown Record Type",
+
+ /* 51 */
+ "Can't Open Trace File",
+ "Session in Fatal Error State",
+ "Partial SSL record received",
+ "Buffer Error, malformed input",
+ "Added to Partial Input",
+
+ /* 56 */
+ "Received a Duplicate Packet",
+ "Received an Out of Order Packet",
+ "Received an Overlap Duplicate Packet",
+ "Received an Overlap Reassembly Begin Duplicate Packet",
+ "Received an Overlap Reassembly End Duplicate Packet",
+
+ /* 61 */
+ "Missed the Client Hello Entirely",
+};
+
+
+/* *nix version uses table above */
+static void GetError(int idx, char* buffer)
+{
+ XSTRNCPY(buffer, msgTable[idx - 1], MAX_ERROR_LEN);
+}
+
+
+#else /* _WIN32 */
+
+
+/* Windows version uses .rc table */
+static void GetError(int idx, char* buffer)
+{
+ if (!LoadStringA(dllModule, idx, buffer, MAX_ERROR_LEN))
+ buffer[0] = 0;
+}
+
+
+#endif /* _WIN32 */
+
+
+/* Packet Buffer for reassembly list and ready list */
+typedef struct PacketBuffer {
+ word32 begin; /* relative sequence begin */
+ word32 end; /* relative sequence end */
+ byte* data; /* actual data */
+ struct PacketBuffer* next; /* next on reassembly list or ready list */
+} PacketBuffer;
+
+
+/* Sniffer Server holds info for each server/port monitored */
+typedef struct SnifferServer {
+ SSL_CTX* ctx; /* SSL context */
+ char address[MAX_SERVER_ADDRESS]; /* passed in server address */
+ word32 server; /* netowrk order address */
+ int port; /* server port */
+ struct SnifferServer* next; /* for list */
+} SnifferServer;
+
+
+/* Session Flags */
+typedef struct Flags {
+ byte side; /* which end is current packet headed */
+ byte serverCipherOn; /* indicates whether cipher is active */
+ byte clientCipherOn; /* indicates whether cipher is active */
+ byte resuming; /* did this session come from resumption */
+ byte cached; /* have we cached this session yet */
+ byte clientHello; /* processed client hello yet, for SSLv2 */
+ byte finCount; /* get both FINs before removing */
+ byte fatalError; /* fatal error state */
+} Flags;
+
+
+/* Out of Order FIN caputre */
+typedef struct FinCaputre {
+ word32 cliFinSeq; /* client relative sequence FIN 0 is no */
+ word32 srvFinSeq; /* server relative sequence FIN, 0 is no */
+ byte cliCounted; /* did we count yet, detects duplicates */
+ byte srvCounted; /* did we count yet, detects duplicates */
+} FinCaputre;
+
+
+/* Sniffer Session holds info for each client/server SSL/TLS session */
+typedef struct SnifferSession {
+ SnifferServer* context; /* server context */
+ SSL* sslServer; /* SSL server side decode */
+ SSL* sslClient; /* SSL client side decode */
+ word32 server; /* server address in network byte order */
+ word32 client; /* client address in network byte order */
+ word16 srvPort; /* server port */
+ word16 cliPort; /* client port */
+ word32 cliSeqStart; /* client start sequence */
+ word32 srvSeqStart; /* server start sequence */
+ word32 cliExpected; /* client expected sequence (relative) */
+ word32 srvExpected; /* server expected sequence (relative) */
+ FinCaputre finCaputre; /* retain out of order FIN s */
+ Flags flags; /* session flags */
+ time_t bornOn; /* born on ticks */
+ PacketBuffer* cliReassemblyList; /* client out of order packets */
+ PacketBuffer* srvReassemblyList; /* server out of order packets */
+ struct SnifferSession* next; /* for hash table list */
+} SnifferSession;
+
+
+/* Sniffer Server List and mutex */
+static SnifferServer* ServerList = 0;
+static CyaSSL_Mutex ServerListMutex;
+
+
+/* Session Hash Table, mutex, and count */
+static SnifferSession* SessionTable[HASH_SIZE];
+static CyaSSL_Mutex SessionMutex;
+static int SessionCount = 0;
+
+
+/* Initialize overall Sniffer */
+void ssl_InitSniffer(void)
+{
+ InitCyaSSL();
+ InitMutex(&ServerListMutex);
+ InitMutex(&SessionMutex);
+}
+
+
+/* Free Sniffer Server's resources/self */
+static void FreeSnifferServer(SnifferServer* server)
+{
+ if (server)
+ SSL_CTX_free(server->ctx);
+ free(server);
+}
+
+
+/* free PacketBuffer's resources/self */
+static void FreePacketBuffer(PacketBuffer* remove)
+{
+ if (remove) {
+ free(remove->data);
+ free(remove);
+ }
+}
+
+
+/* remove PacketBuffer List */
+static void FreePacketList(PacketBuffer* buffer)
+{
+ if (buffer) {
+ PacketBuffer* remove;
+ PacketBuffer* packet = buffer;
+
+ while (packet) {
+ remove = packet;
+ packet = packet->next;
+ FreePacketBuffer(remove);
+ }
+ }
+}
+
+
+/* Free Sniffer Session's resources/self */
+static void FreeSnifferSession(SnifferSession* session)
+{
+ if (session) {
+ SSL_free(session->sslClient);
+ SSL_free(session->sslServer);
+
+ FreePacketList(session->cliReassemblyList);
+ FreePacketList(session->srvReassemblyList);
+ }
+ free(session);
+}
+
+
+/* Free overall Sniffer */
+void ssl_FreeSniffer(void)
+{
+ SnifferServer* server;
+ SnifferServer* removeServer;
+ SnifferSession* session;
+ SnifferSession* removeSession;
+ int i;
+
+ LockMutex(&ServerListMutex);
+ LockMutex(&SessionMutex);
+
+ server = ServerList;
+ while (server) {
+ removeServer = server;
+ server = server->next;
+ FreeSnifferServer(removeServer);
+ }
+
+ for (i = 0; i < HASH_SIZE; i++) {
+ session = SessionTable[i];
+ while (session) {
+ removeSession = session;
+ session = session->next;
+ FreeSnifferSession(removeSession);
+ }
+ }
+
+ UnLockMutex(&SessionMutex);
+ UnLockMutex(&ServerListMutex);
+
+ FreeMutex(&SessionMutex);
+ FreeMutex(&ServerListMutex);
+ FreeCyaSSL();
+}
+
+
+/* Initialize a SnifferServer */
+static void InitSnifferServer(SnifferServer* sniffer)
+{
+ sniffer->ctx = 0;
+ XMEMSET(sniffer->address, 0, MAX_SERVER_ADDRESS);
+ sniffer->server = 0;
+ sniffer->port = 0;
+ sniffer->next = 0;
+}
+
+
+/* Initialize session flags */
+static void InitFlags(Flags* flags)
+{
+ flags->side = 0;
+ flags->serverCipherOn = 0;
+ flags->clientCipherOn = 0;
+ flags->resuming = 0;
+ flags->cached = 0;
+ flags->clientHello = 0;
+ flags->finCount = 0;
+ flags->fatalError = 0;
+}
+
+
+/* Initialize FIN Capture */
+static void InitFinCapture(FinCaputre* cap)
+{
+ cap->cliFinSeq = 0;
+ cap->srvFinSeq = 0;
+ cap->cliCounted = 0;
+ cap->srvCounted = 0;
+}
+
+
+/* Initialize a Sniffer Session */
+static void InitSession(SnifferSession* session)
+{
+ session->context = 0;
+ session->sslServer = 0;
+ session->sslClient = 0;
+ session->server = 0;
+ session->client = 0;
+ session->srvPort = 0;
+ session->cliPort = 0;
+ session->cliSeqStart = 0;
+ session->srvSeqStart = 0;
+ session->cliExpected = 0;
+ session->srvExpected = 0;
+ session->bornOn = 0;
+ session->cliReassemblyList = 0;
+ session->srvReassemblyList = 0;
+ session->next = 0;
+
+ InitFlags(&session->flags);
+ InitFinCapture(&session->finCaputre);
+}
+
+
+/* IP Info from IP Header */
+typedef struct IpInfo {
+ int length; /* length of this header */
+ int total; /* total length of fragment */
+ word32 src; /* network order source address */
+ word32 dst; /* network order destination address */
+} IpInfo;
+
+
+/* TCP Info from TCP Header */
+typedef struct TcpInfo {
+ int srcPort; /* source port */
+ int dstPort; /* source port */
+ int length; /* length of this header */
+ word32 sequence; /* sequence number */
+ byte fin; /* FIN set */
+ byte rst; /* RST set */
+ byte syn; /* SYN set */
+ byte ack; /* ACK set */
+} TcpInfo;
+
+
+/* Tcp Pseudo Header for Checksum calculation */
+typedef struct TcpPseudoHdr {
+ word32 src; /* source address */
+ word32 dst; /* destination address */
+ byte rsv; /* reserved, always 0 */
+ byte protocol; /* IP protocol */
+ word16 legnth; /* tcp header length + data length (doesn't include */
+ /* pseudo header length) network order */
+} TcpPseudoHdr;
+
+
+/* Password Setting Callback */
+static int SetPassword(char* passwd, int sz, int rw, void* userdata)
+{
+ XSTRNCPY(passwd, userdata, sz);
+ return XSTRLEN(userdata);
+}
+
+
+/* Ethernet Header */
+typedef struct EthernetHdr {
+ byte dst[ETHER_IF_ADDR_LEN]; /* destination host address */
+ byte src[ETHER_IF_ADDR_LEN]; /* source host address */
+ word16 type; /* IP, ARP, etc */
+} EthernetHdr;
+
+
+/* IP Header */
+typedef struct IpHdr {
+ byte ver_hl; /* version/header length */
+ byte tos; /* type of service */
+ word16 length; /* total length */
+ word16 id; /* identification */
+ word16 offset; /* fragment offset field */
+ byte ttl; /* time to live */
+ byte protocol; /* protocol */
+ word16 sum; /* checksum */
+ word32 src; /* source address */
+ word32 dst; /* destination address */
+} IpHdr;
+
+
+#define IP_HL(ip) ( (((ip)->ver_hl) & 0x0f) * 4)
+#define IP_V(ip) ( ((ip)->ver_hl) >> 4)
+
+/* TCP Header */
+typedef struct TcpHdr {
+ word16 srcPort; /* source port */
+ word16 dstPort; /* destination port */
+ word32 sequence; /* sequence number */
+ word32 ack; /* acknoledgment number */
+ byte offset; /* data offset, reserved */
+ byte flags; /* option flags */
+ word16 window; /* window */
+ word16 sum; /* checksum */
+ word16 urgent; /* urgent pointer */
+} TcpHdr;
+
+#define TCP_LEN(tcp) ( (((tcp)->offset & 0xf0) >> 4) * 4)
+#define TCP_FIN 0x01
+#define TCP_SYN 0x02
+#define TCP_RST 0x04
+#define TCP_ACK 0x10
+
+
+
+
+
+/* Use platform specific GetError to write to tracfile if tracing */
+static void Trace(int idx)
+{
+ if (TraceOn) {
+ char buffer[MAX_ERROR_LEN];
+ GetError(idx, buffer);
+ fprintf(TraceFile, "\t%s\n", buffer);
+#ifdef DEBUG_SNIFFER
+ fprintf(stderr, "\t%s\n", buffer);
+#endif
+ }
+}
+
+
+/* Show TimeStamp for beginning of packet Trace */
+static void TraceHeader(void)
+{
+ if (TraceOn) {
+ time_t ticks = time(NULL);
+ fprintf(TraceFile, "\n%s", ctime(&ticks));
+ }
+}
+
+
+/* Show Set Server info for Trace */
+static void TraceSetServer(const char* server, int port, const char* keyFile)
+{
+ if (TraceOn) {
+ fprintf(TraceFile, "\tTrying to install a new Sniffer Server with\n");
+ fprintf(TraceFile, "\tserver: %s, port: %d, keyFile: %s\n", server,
+ port, keyFile);
+ }
+}
+
+
+/* Trace got packet number */
+static void TracePacket(void)
+{
+ if (TraceOn) {
+ static word32 packetNumber = 0;
+ fprintf(TraceFile, "\tGot a Packet to decode, packet %u\n",
+ ++packetNumber);
+ }
+}
+
+
+/* Convert network byte order address into human readable */
+static char* IpToS(word32 addr, char* str)
+{
+ byte* p = (byte*)&addr;
+
+ SNPRINTF(str, TRACE_MSG_SZ, "%d.%d.%d.%d", p[0], p[1], p[2], p[3]);
+
+ return str;
+}
+
+
+/* Show destination and source address from Ip Hdr for packet Trace */
+static void TraceIP(IpHdr* iphdr)
+{
+ if (TraceOn) {
+ char src[TRACE_MSG_SZ];
+ char dst[TRACE_MSG_SZ];
+ fprintf(TraceFile, "\tdst:%s src:%s\n", IpToS(iphdr->dst, dst),
+ IpToS(iphdr->src, src));
+ }
+}
+
+
+/* Show destination and source port from Tcp Hdr for packet Trace */
+static void TraceTcp(TcpHdr* tcphdr)
+{
+ if (TraceOn) {
+ fprintf(TraceFile, "\tdstPort:%u srcPort:%u\n", ntohs(tcphdr->dstPort),
+ ntohs(tcphdr->srcPort));
+ }
+}
+
+
+/* Show sequence and payload length for Trace */
+static void TraceSequence(word32 seq, int len)
+{
+ if (TraceOn) {
+ fprintf(TraceFile, "\tSequence:%u, payload length:%d\n", seq, len);
+ }
+}
+
+
+/* Show relative expected and relative received sequences */
+static void TraceRelativeSequence(word32 expected, word32 got)
+{
+ if (TraceOn) {
+ fprintf(TraceFile, "\tExpected sequence:%u, received sequence:%u\n",
+ expected, got);
+ }
+}
+
+
+/* Show server sequence startup from SYN */
+static void TraceServerSyn(word32 seq)
+{
+ if (TraceOn) {
+ fprintf(TraceFile, "\tServer SYN, Sequence Start:%u\n", seq);
+ }
+}
+
+
+/* Show client sequence startup from SYN */
+static void TraceClientSyn(word32 seq)
+{
+ if (TraceOn) {
+ fprintf(TraceFile, "\tClient SYN, Sequence Start:%u\n", seq);
+ }
+}
+
+
+/* Show client FIN capture */
+static void TraceClientFin(word32 finSeq, word32 relSeq)
+{
+ if (TraceOn) {
+ fprintf(TraceFile, "\tClient FIN capture:%u, current SEQ:%u\n",
+ finSeq, relSeq);
+ }
+}
+
+
+/* Show server FIN capture */
+static void TraceServerFin(word32 finSeq, word32 relSeq)
+{
+ if (TraceOn) {
+ fprintf(TraceFile, "\tServer FIN capture:%u, current SEQ:%u\n",
+ finSeq, relSeq);
+ }
+}
+
+
+/* Show number of SSL data bytes decoded, could be 0 (ok) */
+static void TraceGotData(int bytes)
+{
+ if (TraceOn) {
+ fprintf(TraceFile, "\t%d bytes of SSL App data processed\n", bytes);
+ }
+}
+
+
+/* Show bytes added to old SSL App data */
+static void TraceAddedData(int newBytes, int existingBytes)
+{
+ if (TraceOn) {
+ fprintf(TraceFile,
+ "\t%d bytes added to %d exisiting bytes in User Buffer\n",
+ newBytes, existingBytes);
+ }
+}
+
+
+/* Show Stale Session */
+static void TraceStaleSession(SnifferSession* session)
+{
+ if (TraceOn) {
+ fprintf(TraceFile, "\tFound a stale session\n");
+ }
+}
+
+
+/* Show Finding Stale Sessions */
+static void TraceFindingStale()
+{
+ if (TraceOn) {
+ fprintf(TraceFile, "\tTrying to find Stale Sessions\n");
+ }
+}
+
+
+/* Show Removed Session */
+static void TraceRemovedSession()
+{
+ if (TraceOn) {
+ fprintf(TraceFile, "\tRemoved it\n");
+ }
+}
+
+
+/* Set user error string */
+static void SetError(int idx, char* error, SnifferSession* session, int fatal)
+{
+ GetError(idx, error);
+ Trace(idx);
+ if (session && fatal == FATAL_ERROR_STATE)
+ session->flags.fatalError = 1;
+}
+
+
+/* See if this IPV4 network order address has been registered */
+/* return 1 is true, 0 is false */
+static int IsServerRegistered(word32 addr)
+{
+ int ret = 0; /* false */
+ SnifferServer* sniffer;
+
+ LockMutex(&ServerListMutex);
+
+ sniffer = ServerList;
+ while (sniffer) {
+ if (sniffer->server == addr) {
+ ret = 1;
+ break;
+ }
+ sniffer = sniffer->next;
+ }
+
+ UnLockMutex(&ServerListMutex);
+
+ return ret;
+}
+
+
+/* See if this port has been registered to watch */
+/* return 1 is true, 0 is false */
+static int IsPortRegistered(word32 port)
+{
+ int ret = 0; /* false */
+ SnifferServer* sniffer;
+
+ LockMutex(&ServerListMutex);
+
+ sniffer = ServerList;
+ while (sniffer) {
+ if (sniffer->port == port) {
+ ret = 1;
+ break;
+ }
+ sniffer = sniffer->next;
+ }
+
+ UnLockMutex(&ServerListMutex);
+
+ return ret;
+}
+
+
+/* Get SnifferServer from IP and Port */
+static SnifferServer* GetSnifferServer(IpInfo* ipInfo, TcpInfo* tcpInfo)
+{
+ SnifferServer* sniffer;
+
+ LockMutex(&ServerListMutex);
+
+ sniffer = ServerList;
+ while (sniffer) {
+ if (sniffer->port == tcpInfo->srcPort && sniffer->server == ipInfo->src)
+ break;
+ if (sniffer->port == tcpInfo->dstPort && sniffer->server == ipInfo->dst)
+ break;
+ sniffer = sniffer->next;
+ }
+
+ UnLockMutex(&ServerListMutex);
+
+ return sniffer;
+}
+
+
+/* Hash the Session Info, return hash row */
+static word32 SessionHash(IpInfo* ipInfo, TcpInfo* tcpInfo)
+{
+ word32 hash = ipInfo->src * ipInfo->dst;
+ hash *= tcpInfo->srcPort * tcpInfo->dstPort;
+
+ return hash % HASH_SIZE;
+}
+
+
+/* Get Exisiting SnifferSession from IP and Port */
+static SnifferSession* GetSnifferSession(IpInfo* ipInfo, TcpInfo* tcpInfo)
+{
+ SnifferSession* session;
+
+ word32 row = SessionHash(ipInfo, tcpInfo);
+ assert(row >= 0 && row <= HASH_SIZE);
+
+ LockMutex(&SessionMutex);
+
+ session = SessionTable[row];
+ while (session) {
+ if (session->server == ipInfo->src && session->client == ipInfo->dst &&
+ session->srvPort == tcpInfo->srcPort &&
+ session->cliPort == tcpInfo->dstPort)
+ break;
+ if (session->client == ipInfo->src && session->server == ipInfo->dst &&
+ session->cliPort == tcpInfo->srcPort &&
+ session->srvPort == tcpInfo->dstPort)
+ break;
+
+ session = session->next;
+ }
+
+ UnLockMutex(&SessionMutex);
+
+ /* determine side */
+ if (session) {
+ if (ipInfo->dst == session->context->server &&
+ tcpInfo->dstPort == session->context->port)
+ session->flags.side = SERVER_END;
+ else
+ session->flags.side = CLIENT_END;
+ }
+
+ return session;
+}
+
+
+/* Sets the private key for a specific server and port */
+/* returns 0 on success, -1 on error */
+int ssl_SetPrivateKey(const char* serverAddress, int port, const char* keyFile,
+ int keyType, const char* password, char* error)
+{
+ int ret;
+ int type = (keyType == FILETYPE_PEM) ? SSL_FILETYPE_PEM :
+ SSL_FILETYPE_ASN1;
+ SnifferServer* sniffer;
+
+ TraceHeader();
+ TraceSetServer(serverAddress, port, keyFile);
+
+ sniffer = (SnifferServer*)malloc(sizeof(SnifferServer));
+ if (sniffer == NULL) {
+ SetError(MEMORY_STR, error, NULL, 0);
+ return -1;
+ }
+ InitSnifferServer(sniffer);
+
+ XSTRNCPY(sniffer->address, serverAddress, MAX_SERVER_ADDRESS);
+ sniffer->server = inet_addr(sniffer->address);
+ sniffer->port = port;
+
+ /* start in client mode since SSL_new needs a cert for server */
+ sniffer->ctx = SSL_CTX_new(SSLv3_client_method());
+ if (!sniffer->ctx) {
+ SetError(MEMORY_STR, error, NULL, 0);
+ FreeSnifferServer(sniffer);
+ return -1;
+ }
+
+ if (password){
+ SSL_CTX_set_default_passwd_cb(sniffer->ctx, SetPassword);
+ SSL_CTX_set_default_passwd_cb_userdata(sniffer->ctx, (void*)password);
+ }
+ ret = SSL_CTX_use_PrivateKey_file(sniffer->ctx, keyFile, type);
+ if (ret != SSL_SUCCESS) {
+ SetError(KEY_FILE_STR, error, NULL, 0);
+ FreeSnifferServer(sniffer);
+ return -1;
+ }
+ Trace(NEW_SERVER_STR);
+
+ LockMutex(&ServerListMutex);
+
+ sniffer->next = ServerList;
+ ServerList = sniffer;
+
+ UnLockMutex(&ServerListMutex);
+
+ return 0;
+}
+
+
+/* Check IP Header for IPV4, TCP, and a registered server address */
+/* returns 0 on success, -1 on error */
+static int CheckIpHdr(IpHdr* iphdr, IpInfo* info, char* error)
+{
+ int version = IP_V(iphdr);
+
+ TraceIP(iphdr);
+ Trace(IP_CHECK_STR);
+ if (version != IPV4) {
+ SetError(BAD_IPVER_STR, error, NULL, 0);
+ return -1;
+ }
+
+ if (iphdr->protocol != TCP_PROTOCOL) {
+ SetError(BAD_PROTO_STR, error, NULL, 0);
+ return -1;
+ }
+
+ if (!IsServerRegistered(iphdr->src) && !IsServerRegistered(iphdr->dst)) {
+ SetError(SERVER_NOT_REG_STR, error, NULL, 0);
+ return -1;
+ }
+
+ info->length = IP_HL(iphdr);
+ info->total = ntohs(iphdr->length);
+ info->src = iphdr->src;
+ info->dst = iphdr->dst;
+
+ return 0;
+}
+
+
+/* Check TCP Header for a registered port */
+/* returns 0 on success, -1 on error */
+static int CheckTcpHdr(TcpHdr* tcphdr, TcpInfo* info, char* error)
+{
+ TraceTcp(tcphdr);
+ Trace(TCP_CHECK_STR);
+ info->srcPort = ntohs(tcphdr->srcPort);
+ info->dstPort = ntohs(tcphdr->dstPort);
+ info->length = TCP_LEN(tcphdr);
+ info->sequence = ntohl(tcphdr->sequence);
+ info->fin = tcphdr->flags & TCP_FIN;
+ info->rst = tcphdr->flags & TCP_RST;
+ info->syn = tcphdr->flags & TCP_SYN;
+ info->ack = tcphdr->flags & TCP_ACK;
+
+ if (!IsPortRegistered(info->srcPort) && !IsPortRegistered(info->dstPort)) {
+ SetError(SERVER_PORT_NOT_REG_STR, error, NULL, 0);
+ return -1;
+ }
+
+ return 0;
+}
+
+
+/* Decode Record Layer Header */
+static int GetRecordHeader(const byte* input, RecordLayerHeader* rh, int* size)
+{
+ XMEMCPY(rh, input, RECORD_HEADER_SZ);
+ *size = (rh->length[0] << 8) | rh->length[1];
+
+ if (*size > (RECORD_SIZE + MAX_COMP_EXTRA + MAX_MSG_EXTRA))
+ return LENGTH_ERROR;
+
+ return 0;
+}
+
+
+/* Process Client Key Exchange, RSA only */
+static int ProcessClientKeyExchange(const byte* input, int* sslBytes,
+ SnifferSession* session, char* error)
+{
+ word32 idx = 0;
+ RsaKey key;
+ int ret;
+
+ InitRsaKey(&key, 0);
+
+ ret = RsaPrivateKeyDecode(session->context->ctx->privateKey.buffer,
+ &idx, &key, session->context->ctx->privateKey.length);
+ if (ret == 0) {
+ int length = RsaEncryptSize(&key);
+
+ if (IsTLS(session->sslServer))
+ input += 2; /* tls pre length */
+
+ ret = RsaPrivateDecrypt(input, length,
+ session->sslServer->arrays.preMasterSecret, SECRET_LEN, &key);
+
+ if (ret != SECRET_LEN) {
+ SetError(RSA_DECRYPT_STR, error, session, FATAL_ERROR_STATE);
+ FreeRsaKey(&key);
+ return -1;
+ }
+ ret = 0; /* not in error state */
+ session->sslServer->arrays.preMasterSz = SECRET_LEN;
+
+ /* store for client side as well */
+ XMEMCPY(session->sslClient->arrays.preMasterSecret,
+ session->sslServer->arrays.preMasterSecret, SECRET_LEN);
+ session->sslClient->arrays.preMasterSz = SECRET_LEN;
+
+ #ifdef SHOW_SECRETS
+ {
+ int i;
+ printf("pre master secret: ");
+ for (i = 0; i < SECRET_LEN; i++)
+ printf("%02x", session->sslServer->arrays.preMasterSecret[i]);
+ printf("\n");
+ }
+ #endif
+ }
+ else {
+ SetError(RSA_DECODE_STR, error, session, FATAL_ERROR_STATE);
+ FreeRsaKey(&key);
+ return -1;
+ }
+
+ if (SetCipherSpecs(session->sslServer) != 0) {
+ SetError(BAD_CIPHER_SPEC_STR, error, session, FATAL_ERROR_STATE);
+ FreeRsaKey(&key);
+ return -1;
+ }
+
+ if (SetCipherSpecs(session->sslClient) != 0) {
+ SetError(BAD_CIPHER_SPEC_STR, error, session, FATAL_ERROR_STATE);
+ FreeRsaKey(&key);
+ return -1;
+ }
+
+ MakeMasterSecret(session->sslServer);
+ MakeMasterSecret(session->sslClient);
+#ifdef SHOW_SECRETS
+ {
+ int i;
+ printf("server master secret: ");
+ for (i = 0; i < SECRET_LEN; i++)
+ printf("%02x", session->sslServer->arrays.masterSecret[i]);
+ printf("\n");
+
+ printf("client master secret: ");
+ for (i = 0; i < SECRET_LEN; i++)
+ printf("%02x", session->sslClient->arrays.masterSecret[i]);
+ printf("\n");
+
+ printf("server suite = %d\n", session->sslServer->options.cipherSuite);
+ printf("client suite = %d\n", session->sslClient->options.cipherSuite);
+ }
+#endif
+
+ FreeRsaKey(&key);
+ return ret;
+}
+
+
+/* Process Server Hello */
+static int ProcessServerHello(const byte* input, int* sslBytes,
+ SnifferSession* session, char* error)
+{
+ ProtocolVersion pv;
+ byte b;
+ int toRead = sizeof(ProtocolVersion) + RAN_LEN + ENUM_LEN;
+
+ /* make sure we didn't miss ClientHello */
+ if (session->flags.clientHello == 0) {
+ SetError(MISSED_CLIENT_HELLO_STR, error, session, FATAL_ERROR_STATE);
+ return -1;
+ }
+
+ /* make sure can read through session len */
+ if (toRead > *sslBytes) {
+ SetError(SERVER_HELLO_INPUT_STR, error, session, FATAL_ERROR_STATE);
+ return -1;
+ }
+
+ XMEMCPY(&pv, input, sizeof(ProtocolVersion));
+ input += sizeof(ProtocolVersion);
+ *sslBytes -= sizeof(ProtocolVersion);
+
+ session->sslServer->version = pv;
+ session->sslClient->version = pv;
+
+ XMEMCPY(session->sslServer->arrays.serverRandom, input, RAN_LEN);
+ XMEMCPY(session->sslClient->arrays.serverRandom, input, RAN_LEN);
+ input += RAN_LEN;
+ *sslBytes -= RAN_LEN;
+
+ b = *input++;
+ *sslBytes -= 1;
+
+ /* make sure can read through compression */
+ if ( (b + SUITE_LEN + ENUM_LEN) > *sslBytes) {
+ SetError(SERVER_HELLO_INPUT_STR, error, session, FATAL_ERROR_STATE);
+ return -1;
+ }
+ XMEMCPY(session->sslServer->arrays.sessionID, input, ID_LEN);
+ input += b;
+ *sslBytes -= b;
+
+ (void)*input++; /* eat first byte, always 0 */
+ b = *input++;
+ session->sslServer->options.cipherSuite = b;
+ session->sslClient->options.cipherSuite = b;
+ *sslBytes -= SUITE_LEN;
+
+ if (XMEMCMP(session->sslServer->arrays.sessionID,
+ session->sslClient->arrays.sessionID, ID_LEN) == 0) {
+ /* resuming */
+ SSL_SESSION* resume = GetSession(session->sslServer,
+ session->sslServer->arrays.masterSecret);
+ if (resume == NULL) {
+ SetError(BAD_SESSION_RESUME_STR, error, session, FATAL_ERROR_STATE);
+ return -1;
+ }
+ /* make sure client has master secret too */
+ XMEMCPY(session->sslClient->arrays.masterSecret,
+ session->sslServer->arrays.masterSecret, SECRET_LEN);
+ session->flags.resuming = 1;
+
+ Trace(SERVER_DID_RESUMPTION_STR);
+ if (SetCipherSpecs(session->sslServer) != 0) {
+ SetError(BAD_CIPHER_SPEC_STR, error, session, FATAL_ERROR_STATE);
+ return -1;
+ }
+
+ if (SetCipherSpecs(session->sslClient) != 0) {
+ SetError(BAD_CIPHER_SPEC_STR, error, session, FATAL_ERROR_STATE);
+ return -1;
+ }
+
+ if (session->sslServer->options.tls) {
+ DeriveTlsKeys(session->sslServer);
+ DeriveTlsKeys(session->sslClient);
+ }
+ else {
+ DeriveKeys(session->sslServer);
+ DeriveKeys(session->sslClient);
+ }
+ }
+#ifdef SHOW_SECRETS
+ {
+ int i;
+ printf("cipher suite = 0x%02x\n",
+ session->sslServer->options.cipherSuite);
+ printf("server random: ");
+ for (i = 0; i < RAN_LEN; i++)
+ printf("%02x", session->sslServer->arrays.serverRandom[i]);
+ printf("\n");
+ }
+#endif
+ return 0;
+}
+
+
+/* Process normal Client Hello */
+static int ProcessClientHello(const byte* input, int* sslBytes,
+ SnifferSession* session, char* error)
+{
+ byte sessionLen;
+ int toRead = sizeof(ProtocolVersion) + RAN_LEN + ENUM_LEN;
+
+ session->flags.clientHello = 1; /* don't process again */
+
+ /* make sure can read up to session len */
+ if (toRead > *sslBytes) {
+ SetError(CLIENT_HELLO_INPUT_STR, error, session, FATAL_ERROR_STATE);
+ return -1;
+ }
+
+ /* skip, get negotiated one from server hello */
+ input += sizeof(ProtocolVersion);
+ *sslBytes -= sizeof(ProtocolVersion);
+
+ XMEMCPY(session->sslServer->arrays.clientRandom, input, RAN_LEN);
+ XMEMCPY(session->sslClient->arrays.clientRandom, input, RAN_LEN);
+
+ input += RAN_LEN;
+ *sslBytes -= RAN_LEN;
+
+ /* store session in case trying to resume */
+ sessionLen = *input++;
+ if (sessionLen) {
+ if (ID_LEN > *sslBytes) {
+ SetError(CLIENT_HELLO_INPUT_STR, error, session, FATAL_ERROR_STATE);
+ return -1;
+ }
+ Trace(CLIENT_RESUME_TRY_STR);
+ XMEMCPY(session->sslClient->arrays.sessionID, input, ID_LEN);
+ }
+#ifdef SHOW_SECRETS
+ {
+ int i;
+ printf("client random: ");
+ for (i = 0; i < RAN_LEN; i++)
+ printf("%02x", session->sslServer->arrays.clientRandom[i]);
+ printf("\n");
+ }
+#endif
+
+ return 0;
+}
+
+
+/* Process HandShake input */
+static int DoHandShake(const byte* input, int* sslBytes, IpInfo* ipInfo,
+ TcpInfo* tcpInfo, SnifferSession* session, char* error)
+{
+ byte type;
+ int size;
+ int ret = 0;
+
+ if (*sslBytes < HANDSHAKE_HEADER_SZ) {
+ SetError(HANDSHAKE_INPUT_STR, error, session, FATAL_ERROR_STATE);
+ return -1;
+ }
+ type = input[0];
+ size = (input[1] << 16) | (input[2] << 8) | input[3];
+
+ input += HANDSHAKE_HEADER_SZ;
+ *sslBytes -= HANDSHAKE_HEADER_SZ;
+
+ if (*sslBytes < size) {
+ SetError(HANDSHAKE_INPUT_STR, error, session, FATAL_ERROR_STATE);
+ return -1;
+ }
+
+ switch (type) {
+ case hello_verify_request:
+ Trace(GOT_HELLO_VERIFY_STR);
+ break;
+ case server_hello:
+ Trace(GOT_SERVER_HELLO_STR);
+ ret = ProcessServerHello(input, sslBytes, session, error);
+ break;
+ case certificate_request:
+ Trace(GOT_CERT_REQ_STR);
+ break;
+ case server_key_exchange:
+ Trace(GOT_SERVER_KEY_EX_STR);
+ break;
+ case certificate:
+ Trace(GOT_CERT_STR);
+ break;
+ case server_hello_done:
+ Trace(GOT_SERVER_HELLO_DONE_STR);
+ break;
+ case finished:
+ Trace(GOT_FINISHED_STR);
+ {
+ SSL* ssl;
+ word32 inOutIdx = 0;
+
+ if (session->flags.side == SERVER_END)
+ ssl = session->sslServer;
+ else
+ ssl = session->sslClient;
+ ret = DoFinished(ssl, input, &inOutIdx, SNIFF);
+
+ if (ret == 0 && session->flags.cached == 0) {
+ AddSession(session->sslServer);
+ session->flags.cached = 1;
+ }
+ }
+ break;
+ case client_hello:
+ Trace(GOT_CLIENT_HELLO_STR);
+ ret = ProcessClientHello(input, sslBytes, session, error);
+ break;
+ case client_key_exchange:
+ Trace(GOT_CLIENT_KEY_EX_STR);
+ ret = ProcessClientKeyExchange(input, sslBytes, session, error);
+ break;
+ case certificate_verify:
+ Trace(GOT_CERT_VER_STR);
+ break;
+ default:
+ SetError(GOT_UNKNOWN_HANDSHAKE_STR, error, session, 0);
+ return -1;
+ }
+
+ return ret;
+}
+
+
+/* Decrypt input into plain output */
+static void Decrypt(SSL* ssl, byte* output, const byte* input, word32 sz)
+{
+ switch (ssl->specs.bulk_cipher_algorithm) {
+ #ifdef BUILD_ARC4
+ case rc4:
+ Arc4Process(&ssl->decrypt.arc4, output, input, sz);
+ break;
+ #endif
+
+ #ifdef BUILD_DES3
+ case triple_des:
+ Des3_CbcDecrypt(&ssl->decrypt.des3, output, input, sz);
+ break;
+ #endif
+
+ #ifdef BUILD_AES
+ case aes:
+ AesCbcDecrypt(&ssl->decrypt.aes, output, input, sz);
+ break;
+ #endif
+
+ #ifdef BUILD_HC128
+ case hc128:
+ Hc128_Process(&ssl->decrypt.hc128, output, input, sz);
+ break;
+ #endif
+
+ #ifdef BUILD_RABBIT
+ case rabbit:
+ RabbitProcess(&ssl->decrypt.rabbit, output, input, sz);
+ break;
+ #endif
+ }
+}
+
+
+/* Decrypt input message into output, adjust output steam if needed */
+static const byte* DecryptMessage(SSL* ssl, const byte* input, word32 sz,
+ byte* output)
+{
+ Decrypt(ssl, output, input, sz);
+ ssl->keys.encryptSz = sz;
+ if (ssl->options.tls1_1 && ssl->specs.cipher_type == block)
+ return output + ssl->specs.block_size; /* go past TLSv1.1 IV */
+
+ return output;
+}
+
+
+/* remove session from table, use rowHint if no info (means we have a lock) */
+static void RemoveSession(SnifferSession* session, IpInfo* ipInfo,
+ TcpInfo* tcpInfo, word32 rowHint)
+{
+ SnifferSession* previous = 0;
+ SnifferSession* current;
+ word32 row = rowHint;
+ int haveLock = 0;
+
+ if (ipInfo && tcpInfo)
+ row = SessionHash(ipInfo, tcpInfo);
+ else
+ haveLock = 1;
+
+ assert(row >= 0 && row <= HASH_SIZE);
+ Trace(REMOVE_SESSION_STR);
+
+ if (!haveLock)
+ LockMutex(&SessionMutex);
+
+ current = SessionTable[row];
+
+ while (current) {
+ if (current == session) {
+ if (previous)
+ previous->next = current->next;
+ else
+ SessionTable[row] = current->next;
+ FreeSnifferSession(session);
+ TraceRemovedSession();
+ break;
+ }
+ previous = current;
+ current = current->next;
+ }
+
+ if (!haveLock)
+ UnLockMutex(&SessionMutex);
+}
+
+
+/* Remove stale sessions from the Session Table, have a lock */
+static void RemoveStaleSessions()
+{
+ word32 i;
+ SnifferSession* session;
+
+ for (i = 0; i < HASH_SIZE; i++) {
+ session = SessionTable[i];
+ while (session) {
+ SnifferSession* next = session->next;
+ if (time(NULL) >= session->bornOn + SNIFFER_TIMEOUT) {
+ TraceStaleSession(session);
+ RemoveSession(session, NULL, NULL, i);
+ }
+ session = next;
+ }
+ }
+}
+
+
+/* Create a new Sniffer Session */
+static SnifferSession* CreateSession(IpInfo* ipInfo, TcpInfo* tcpInfo,
+ char* error)
+{
+ SnifferSession* session = 0;
+ int row;
+
+ Trace(NEW_SESSION_STR);
+ /* create a new one */
+ session = (SnifferSession*)malloc(sizeof(SnifferSession));
+ if (session == NULL) {
+ SetError(MEMORY_STR, error, NULL, 0);
+ return 0;
+ }
+ InitSession(session);
+ session->server = ipInfo->dst;
+ session->client = ipInfo->src;
+ session->srvPort = tcpInfo->dstPort;
+ session->cliPort = tcpInfo->srcPort;
+ session->cliSeqStart = tcpInfo->sequence;
+ session->cliExpected = 1; /* relative */
+ session->bornOn = time(NULL);
+
+ session->context = GetSnifferServer(ipInfo, tcpInfo);
+ if (session->context == NULL) {
+ SetError(SERVER_NOT_REG_STR, error, NULL, 0);
+ free(session);
+ return 0;
+ }
+
+ session->sslServer = SSL_new(session->context->ctx);
+ session->sslClient = SSL_new(session->context->ctx);
+ if (session->sslClient == NULL) {
+ if (session->sslServer) {
+ SSL_free(session->sslClient);
+ session->sslClient = 0;
+ }
+ SetError(BAD_NEW_SSL_STR, error, session, FATAL_ERROR_STATE);
+ free(session);
+ return 0;
+ }
+ /* put server back into server mode */
+ session->sslServer->options.side = SERVER_END;
+
+ row = SessionHash(ipInfo, tcpInfo);
+
+ /* add it to the session table */
+ LockMutex(&SessionMutex);
+
+ session->next = SessionTable[row];
+ SessionTable[row] = session;
+
+ SessionCount++;
+
+ if ( (SessionCount % HASH_SIZE) == 0) {
+ TraceFindingStale();
+ RemoveStaleSessions();
+ }
+
+ UnLockMutex(&SessionMutex);
+
+ /* determine headed side */
+ if (ipInfo->dst == session->context->server &&
+ tcpInfo->dstPort == session->context->port)
+ session->flags.side = SERVER_END;
+ else
+ session->flags.side = CLIENT_END;
+
+ return session;
+}
+
+
+/* Process Old Client Hello Input */
+static int DoOldHello(SnifferSession* session, const byte* sslFrame,
+ int* rhSize, int* sslBytes, char* error)
+{
+ const byte* input = sslFrame;
+ byte b0, b1;
+ word32 idx = 0;
+ int ret;
+
+ Trace(GOT_OLD_CLIENT_HELLO_STR);
+ session->flags.clientHello = 1; /* don't process again */
+ b0 = *input++;
+ b1 = *input++;
+ *sslBytes -= 2;
+ *rhSize = ((b0 & 0x7f) << 8) | b1;
+
+ if (*rhSize > *sslBytes) {
+ SetError(OLD_CLIENT_INPUT_STR, error, session, FATAL_ERROR_STATE);
+ return -1;
+ }
+
+ ret = ProcessOldClientHello(session->sslServer, input, &idx, *sslBytes,
+ *rhSize);
+ if (ret < 0) {
+ SetError(BAD_OLD_CLIENT_STR, error, session, FATAL_ERROR_STATE);
+ return -1;
+ }
+
+ Trace(OLD_CLIENT_OK_STR);
+ XMEMCPY(session->sslClient->arrays.clientRandom,
+ session->sslServer->arrays.clientRandom, RAN_LEN);
+
+ *sslBytes -= *rhSize;
+ return 0;
+}
+
+
+/* Calculate the TCP checksum, see RFC 1071 */
+/* return 0 for success, -1 on error */
+/* can be called from decode() with
+ TcpChecksum(&ipInfo, &tcpInfo, sslBytes, packet + ipInfo.length);
+ could also add a 64bit version if type available and using this
+*/
+int TcpChecksum(IpInfo* ipInfo, TcpInfo* tcpInfo, int dataLen,
+ const byte* packet)
+{
+ TcpPseudoHdr pseudo;
+ int count = PSEUDO_HDR_SZ;
+ const word16* data = (word16*)&pseudo;
+ word32 sum = 0;
+ word16 checksum;
+
+ pseudo.src = ipInfo->src;
+ pseudo.dst = ipInfo->dst;
+ pseudo.rsv = 0;
+ pseudo.protocol = TCP_PROTO;
+ pseudo.legnth = htons(tcpInfo->length + dataLen);
+
+ /* pseudo header sum */
+ while (count >= 2) {
+ sum += *data++;
+ count -= 2;
+ }
+
+ count = tcpInfo->length + dataLen;
+ data = (word16*)packet;
+
+ /* main sum */
+ while (count > 1) {
+ sum += *data++;
+ count -=2;
+ }
+
+ /* get left-over, if any */
+ packet = (byte*)data;
+ if (count > 0) {
+ sum += *packet;
+ }
+
+ /* fold 32bit sum into 16 bits */
+ while (sum >> 16)
+ sum = (sum & 0xffff) + (sum >> 16);
+
+ checksum = (word16)~sum;
+ /* checksum should now equal 0, since included already calcd checksum */
+ /* field, but tcp checksum offloading could negate calculation */
+ if (checksum == 0)
+ return 0;
+ return -1;
+}
+
+
+/* Check IP and TCP headers, set payload */
+/* returns 0 on success, -1 on error */
+int CheckHeaders(IpInfo* ipInfo, TcpInfo* tcpInfo, const byte* packet,
+ int length, const byte** sslFrame, int* sslBytes, char* error)
+{
+ TraceHeader();
+ TracePacket();
+ if (length < IP_HDR_SZ) {
+ SetError(PACKET_HDR_SHORT_STR, error, NULL, 0);
+ return -1;
+ }
+ if (CheckIpHdr((IpHdr*)packet, ipInfo, error) != 0)
+ return -1;
+
+ if (length < (ipInfo->length + TCP_HDR_SZ)) {
+ SetError(PACKET_HDR_SHORT_STR, error, NULL, 0);
+ return -1;
+ }
+ if (CheckTcpHdr((TcpHdr*)(packet + ipInfo->length), tcpInfo, error) != 0)
+ return -1;
+
+ *sslFrame = packet + ipInfo->length + tcpInfo->length;
+ if (*sslFrame > packet + length) {
+ SetError(PACKET_HDR_SHORT_STR, error, NULL, 0);
+ return -1;
+ }
+ *sslBytes = packet + length - *sslFrame;
+
+ return 0;
+}
+
+
+/* Create or Find existing session */
+/* returns 0 on success (continue), -1 on error, 1 on success (end) */
+static int CheckSession(IpInfo* ipInfo, TcpInfo* tcpInfo, int sslBytes,
+ SnifferSession** session, char* error)
+{
+ /* create a new SnifferSession on client SYN */
+ if (tcpInfo->syn && !tcpInfo->ack) {
+ TraceClientSyn(tcpInfo->sequence);
+ *session = CreateSession(ipInfo, tcpInfo, error);
+ if (*session == NULL) {
+ *session = GetSnifferSession(ipInfo, tcpInfo);
+ /* already had exisiting, so OK */
+ if (*session)
+ return 1;
+
+ SetError(MEMORY_STR, error, NULL, 0);
+ return -1;
+ }
+ return 1;
+ }
+ /* get existing sniffer session */
+ else {
+ *session = GetSnifferSession(ipInfo, tcpInfo);
+ if (*session == NULL) {
+ /* don't worry about extraneous RST or duplicate FINs */
+ if (tcpInfo->fin || tcpInfo->rst)
+ return 1;
+ /* don't worry about duplicate ACKs either */
+ if (sslBytes == 0 && tcpInfo->ack)
+ return 1;
+
+ SetError(BAD_SESSION_STR, error, NULL, 0);
+ return -1;
+ }
+ }
+ return 0;
+}
+
+
+#ifndef min
+
+static INLINE word32 min(word32 a, word32 b)
+{
+ return a > b ? b : a;
+}
+
+#endif
+
+
+/* Create a Packet Buffer from *begin - end, adjust new *begin and bytesLeft */
+static PacketBuffer* CreateBuffer(word32* begin, word32 end, const byte* data,
+ int* bytesLeft)
+{
+ PacketBuffer* pb;
+
+ int added = end - *begin + 1;
+ assert(*begin <= end);
+
+ pb = (PacketBuffer*)malloc(sizeof(PacketBuffer));
+ if (pb == NULL) return NULL;
+
+ pb->next = 0;
+ pb->begin = *begin;
+ pb->end = end;
+ pb->data = (byte*)malloc(added);
+
+ if (pb->data == NULL) {
+ free(pb);
+ return NULL;
+ }
+ XMEMCPY(pb->data, data, added);
+
+ *bytesLeft -= added;
+ *begin = pb->end + 1;
+
+ return pb;
+}
+
+
+/* Add sslFrame to Reassembly List */
+/* returns 1 (end) on success, -1, on error */
+static int AddToReassembly(byte from, word32 seq, const byte* sslFrame,
+ int sslBytes, SnifferSession* session, char* error)
+{
+ PacketBuffer* add;
+ PacketBuffer** front = (from == SERVER_END) ? &session->cliReassemblyList:
+ &session->srvReassemblyList;
+ PacketBuffer* curr = *front;
+ PacketBuffer* prev = curr;
+
+ word32 startSeq = seq;
+ word32 added;
+ int bytesLeft = sslBytes; /* could be overlapping fragment */
+
+ /* if list is empty add full frame to front */
+ if (!curr) {
+ add = CreateBuffer(&seq, seq + sslBytes - 1, sslFrame, &bytesLeft);
+ if (add == NULL) {
+ SetError(MEMORY_STR, error, session, FATAL_ERROR_STATE);
+ return -1;
+ }
+ *front = add;
+ return 1;
+ }
+
+ /* add to front if before current front, up to next->begin */
+ if (seq < curr->begin) {
+ word32 end = seq + sslBytes - 1;
+
+ if (end >= curr->begin)
+ end = curr->begin - 1;
+
+ add = CreateBuffer(&seq, end, sslFrame, &bytesLeft);
+ if (add == NULL) {
+ SetError(MEMORY_STR, error, session, FATAL_ERROR_STATE);
+ return -1;
+ }
+ add->next = curr;
+ *front = add;
+ }
+
+ /* while we have bytes left, try to find a gap to fill */
+ while (bytesLeft > 0) {
+ /* get previous packet in list */
+ while (curr && (seq >= curr->begin)) {
+ prev = curr;
+ curr = curr->next;
+ }
+
+ /* don't add duplicate data */
+ if (prev->end >= seq) {
+ if ( (seq + bytesLeft - 1) <= prev->end)
+ return 1;
+ seq = prev->end + 1;
+ bytesLeft = startSeq + sslBytes - seq;
+ }
+
+ if (!curr)
+ /* we're at the end */
+ added = bytesLeft;
+ else
+ /* we're in between two frames */
+ added = min((word32)bytesLeft, curr->begin - seq);
+
+ /* data already there */
+ if (added == 0)
+ continue;
+
+ add = CreateBuffer(&seq, seq + added - 1, &sslFrame[seq - startSeq],
+ &bytesLeft);
+ if (add == NULL) {
+ SetError(MEMORY_STR, error, session, FATAL_ERROR_STATE);
+ return -1;
+ }
+ add->next = prev->next;
+ prev->next = add;
+ }
+ return 1;
+}
+
+
+/* Add out of order FIN capture */
+/* returns 1 for success (end) */
+static int AddFinCapture(SnifferSession* session, word32 sequence)
+{
+ if (session->flags.side == SERVER_END) {
+ if (session->finCaputre.cliCounted == 0)
+ session->finCaputre.cliFinSeq = sequence;
+ }
+ else {
+ if (session->finCaputre.srvCounted == 0)
+ session->finCaputre.srvFinSeq = sequence;
+ }
+ return 1;
+}
+
+
+/* Adjust incoming sequence based on side */
+/* returns 0 on success (continue), -1 on error, 1 on success (end) */
+static int AdjustSequence(TcpInfo* tcpInfo, SnifferSession* session,
+ int* sslBytes, const byte** sslFrame, char* error)
+{
+ word32 seqStart = (session->flags.side == SERVER_END) ?
+ session->cliSeqStart :session->srvSeqStart;
+ word32 real = tcpInfo->sequence - seqStart;
+ word32* expected = (session->flags.side == SERVER_END) ?
+ &session->cliExpected : &session->srvExpected;
+ PacketBuffer* reassemblyList = (session->flags.side == SERVER_END) ?
+ session->cliReassemblyList : session->srvReassemblyList;
+
+ /* handle rollover of sequence */
+ if (tcpInfo->sequence < seqStart)
+ real = 0xffffffffU - seqStart + tcpInfo->sequence;
+
+ TraceRelativeSequence(*expected, real);
+
+ if (real < *expected) {
+ Trace(DUPLICATE_STR);
+ if (real + *sslBytes > *expected) {
+ int overlap = *expected - real;
+ Trace(OVERLAP_DUPLICATE_STR);
+
+ /* adjust to expected, remove duplicate */
+ *sslFrame += overlap;
+ *sslBytes -= overlap;
+
+ if (reassemblyList) {
+ word32 newEnd = *expected + *sslBytes;
+
+ if (newEnd > reassemblyList->begin) {
+ Trace(OVERLAP_REASSEMBLY_BEGIN_STR);
+
+ /* remove bytes already on reassembly list */
+ *sslBytes -= newEnd - reassemblyList->begin;
+ }
+ if (newEnd > reassemblyList->end) {
+ Trace(OVERLAP_REASSEMBLY_END_STR);
+
+ /* may be past reassembly list end (could have more on list)
+ so try to add what's past the front->end */
+ AddToReassembly(session->flags.side, reassemblyList->end +1,
+ *sslFrame + reassemblyList->end - *expected + 1,
+ newEnd - reassemblyList->end, session, error);
+ }
+ }
+ }
+ else
+ return 1;
+ }
+ else if (real > *expected) {
+ Trace(OUT_OF_ORDER_STR);
+ if (*sslBytes > 0)
+ return AddToReassembly(session->flags.side, real, *sslFrame,
+ *sslBytes, session, error);
+ else if (tcpInfo->fin)
+ return AddFinCapture(session, real);
+ }
+ /* got expected sequence */
+ *expected += *sslBytes;
+ if (tcpInfo->fin)
+ *expected += 1;
+
+ return 0;
+}
+
+
+/* Check TCP Sequence status */
+/* returns 0 on success (continue), -1 on error, 1 on success (end) */
+static int CheckSequence(IpInfo* ipInfo, TcpInfo* tcpInfo,
+ SnifferSession* session, int* sslBytes,
+ const byte** sslFrame, char* error)
+{
+ int actualLen;
+
+ /* init SEQ from server to client */
+ if (tcpInfo->syn && tcpInfo->ack) {
+ session->srvSeqStart = tcpInfo->sequence;
+ session->srvExpected = 1;
+ TraceServerSyn(tcpInfo->sequence);
+ return 1;
+ }
+
+ /* adjust potential ethernet trailer */
+ actualLen = ipInfo->total - ipInfo->length - tcpInfo->length;
+ if (*sslBytes > actualLen) {
+ *sslBytes = actualLen;
+ }
+
+ TraceSequence(tcpInfo->sequence, *sslBytes);
+
+ return AdjustSequence(tcpInfo, session, sslBytes, sslFrame, error);
+}
+
+
+/* Check Status before record processing */
+/* returns 0 on success (continue), -1 on error, 1 on success (end) */
+static int CheckPreRecord(IpInfo* ipInfo, TcpInfo* tcpInfo,
+ const byte** sslFrame, SnifferSession* session,
+ int* sslBytes, const byte** end, char* error)
+{
+ word32 length;
+ SSL* ssl = (session->flags.side == SERVER_END) ? session->sslServer :
+ session->sslClient;
+ /* remove SnifferSession on 2nd FIN or RST */
+ if (tcpInfo->fin || tcpInfo->rst) {
+ /* flag FIN and RST */
+ if (tcpInfo->fin)
+ session->flags.finCount += 1;
+ else if (tcpInfo->rst)
+ session->flags.finCount += 2;
+
+ if (session->flags.finCount >= 2) {
+ RemoveSession(session, ipInfo, tcpInfo, 0);
+ return 1;
+ }
+ }
+
+ if (session->flags.fatalError == FATAL_ERROR_STATE) {
+ SetError(FATAL_ERROR_STR, error, NULL, 0);
+ return -1;
+ }
+
+ if (*sslBytes == 0) {
+ Trace(NO_DATA_STR);
+ return 1;
+ }
+
+ /* if current partial data, add to end of partial */
+ if ( (length = ssl->buffers.inputBuffer.length) ) {
+ Trace(PARTIAL_ADD_STR);
+
+ if ( (*sslBytes + length) > ssl->buffers.inputBuffer.bufferSize) {
+ SetError(BUFFER_ERROR_STR, error, session, FATAL_ERROR_STATE);
+ return -1;
+ }
+ XMEMCPY(&ssl->buffers.inputBuffer.buffer[length], *sslFrame, *sslBytes);
+ *sslBytes += length;
+ ssl->buffers.inputBuffer.length = *sslBytes;
+ *sslFrame = ssl->buffers.inputBuffer.buffer;
+ *end = *sslFrame + *sslBytes;
+ }
+
+ if (session->flags.clientHello == 0 && **sslFrame != handshake) {
+ int rhSize;
+ int ret = DoOldHello(session, *sslFrame, &rhSize, sslBytes, error);
+ if (ret < 0)
+ return -1; /* error already set */
+ if (*sslBytes <= 0)
+ return 1;
+ }
+
+ return 0;
+}
+
+
+/* See if input on the reassembly list is ready for consuming */
+/* returns 1 for TRUE, 0 for FALSE */
+static int HaveMoreInput(SnifferSession* session, const byte** sslFrame,
+ int* sslBytes, const byte** end)
+{
+ /* sequence and reassembly based on from, not to */
+ int moreInput = 0;
+ PacketBuffer** front = (session->flags.side == SERVER_END) ?
+ &session->cliReassemblyList : &session->srvReassemblyList;
+ word32* expected = (session->flags.side == SERVER_END) ?
+ &session->cliExpected : &session->srvExpected;
+ /* buffer is on receiving end */
+ word32* length = (session->flags.side == SERVER_END) ?
+ &session->sslServer->buffers.inputBuffer.length :
+ &session->sslClient->buffers.inputBuffer.length;
+ byte* buffer = (session->flags.side == SERVER_END) ?
+ session->sslServer->buffers.inputBuffer.buffer :
+ session->sslClient->buffers.inputBuffer.buffer;
+
+ while (*front && ((*front)->begin == *expected) ) {
+ word32 room = STATIC_BUFFER_LEN - *length;
+ word32 packetLen = (*front)->end - (*front)->begin + 1;
+
+ if (packetLen <= room) {
+ PacketBuffer* remove = *front;
+
+ XMEMCPY(&buffer[*length], (*front)->data, packetLen);
+ *length += packetLen;
+ *expected += packetLen;
+
+ /* remove used packet */
+ *front = (*front)->next;
+ FreePacketBuffer(remove);
+
+ moreInput = 1;
+ }
+ else
+ break;
+ }
+ if (moreInput) {
+ *sslFrame = buffer;
+ *sslBytes = *length;
+ *end = buffer + *length;
+ }
+ return moreInput;
+}
+
+
+
+/* Process Message(s) from sslFrame */
+/* return Number of bytes on success, 0 for no data yet, and -1 on error */
+static int ProcessMessage(IpInfo* ipInfo, TcpInfo* tcpInfo,const byte* sslFrame,
+ SnifferSession* session, int sslBytes, byte* data,
+ const byte* end, char* error)
+{
+ const byte* sslBegin = sslFrame;
+ const byte* tmp;
+ RecordLayerHeader rh;
+ int rhSize;
+ int ret;
+ int decoded = 0; /* bytes stored for user in data */
+ int notEnough; /* notEnough bytes yet flag */
+ SSL* ssl = (session->flags.side == SERVER_END) ?
+ session->sslServer : session->sslClient;
+doMessage:
+ notEnough = 0;
+ if (sslBytes >= RECORD_HEADER_SZ) {
+ if (GetRecordHeader(sslFrame, &rh, &rhSize) != 0) {
+ SetError(BAD_RECORD_HDR_STR, error, session, FATAL_ERROR_STATE);
+ return -1;
+ }
+ }
+ else
+ notEnough = 1;
+
+ if (notEnough || rhSize > (sslBytes - RECORD_HEADER_SZ)) {
+ /* don't have enough input yet to process full SSL record */
+ Trace(PARTIAL_INPUT_STR);
+
+ /* store partial if not there already or we advanced */
+ if (ssl->buffers.inputBuffer.length == 0 || sslBegin != sslFrame) {
+ if (sslBytes > ssl->buffers.inputBuffer.bufferSize) {
+ SetError(BUFFER_ERROR_STR, error, session, FATAL_ERROR_STATE);
+ return -1;
+ }
+ XMEMCPY(ssl->buffers.inputBuffer.buffer, sslFrame, sslBytes);
+ ssl->buffers.inputBuffer.length = sslBytes;
+ }
+ if (HaveMoreInput(session, &sslFrame, &sslBytes, &end))
+ goto doMessage;
+ return decoded;
+ }
+ sslFrame += RECORD_HEADER_SZ;
+ sslBytes -= RECORD_HEADER_SZ;
+ tmp = sslFrame + rhSize; /* may have more than one record to process */
+
+ /* decrypt if needed */
+ if (session->flags.side == SERVER_END && session->flags.serverCipherOn)
+ sslFrame = DecryptMessage(ssl, sslFrame, rhSize,
+ ssl->buffers.outputBuffer.buffer);
+ else if (session->flags.side == CLIENT_END && session->flags.clientCipherOn)
+ sslFrame = DecryptMessage(ssl, sslFrame, rhSize,
+ ssl->buffers.outputBuffer.buffer);
+
+ switch ((enum ContentType)rh.type) {
+ case handshake:
+ Trace(GOT_HANDSHAKE_STR);
+ ret = DoHandShake(sslFrame, &sslBytes, ipInfo, tcpInfo, session,
+ error);
+ if (ret != 0) {
+ if (session->flags.fatalError == 0)
+ SetError(BAD_HANDSHAKE_STR,error,session,FATAL_ERROR_STATE);
+ return -1;
+ }
+ break;
+ case change_cipher_spec:
+ if (session->flags.side == SERVER_END)
+ session->flags.serverCipherOn = 1;
+ else
+ session->flags.clientCipherOn = 1;
+ Trace(GOT_CHANGE_CIPHER_STR);
+ break;
+ case application_data:
+ Trace(GOT_APP_DATA_STR);
+ {
+ word32 inOutIdx = 0;
+
+ ret = DoApplicationData(ssl, (byte*)sslFrame, &inOutIdx);
+ if (ret == 0) {
+ ret = ssl->buffers.clearOutputBuffer.length;
+ TraceGotData(ret);
+ if (ret) { /* may be blank message */
+ XMEMCPY(&data[decoded],
+ ssl->buffers.clearOutputBuffer.buffer, ret);
+ TraceAddedData(ret, decoded);
+ decoded += ret;
+ ssl->buffers.clearOutputBuffer.length = 0;
+ }
+ }
+ else {
+ SetError(BAD_APP_DATA_STR, error,session,FATAL_ERROR_STATE);
+ return -1;
+ }
+ }
+ break;
+ case alert:
+ Trace(GOT_ALERT_STR);
+ break;
+ default:
+ SetError(GOT_UNKNOWN_RECORD_STR, error, session, FATAL_ERROR_STATE);
+ return -1;
+ }
+
+ if (tmp < end) {
+ Trace(ANOTHER_MSG_STR);
+ sslFrame = tmp;
+ sslBytes = end - tmp;
+ goto doMessage;
+ }
+
+ /* clear used input */
+ ssl->buffers.inputBuffer.length = 0;
+
+ /* could have more input ready now */
+ if (HaveMoreInput(session, &sslFrame, &sslBytes, &end))
+ goto doMessage;
+
+ return decoded;
+}
+
+
+/* See if we need to process any pending FIN captures */
+static void CheckFinCapture(IpInfo* ipInfo, TcpInfo* tcpInfo,
+ SnifferSession* session)
+{
+ if (session->finCaputre.cliFinSeq && session->finCaputre.cliFinSeq <=
+ session->cliExpected) {
+ if (session->finCaputre.cliCounted == 0) {
+ session->flags.finCount += 1;
+ session->finCaputre.cliCounted = 1;
+ TraceClientFin(session->finCaputre.cliFinSeq, session->cliExpected);
+ }
+ }
+
+ if (session->finCaputre.srvFinSeq && session->finCaputre.srvFinSeq <=
+ session->srvExpected) {
+ if (session->finCaputre.srvCounted == 0) {
+ session->flags.finCount += 1;
+ session->finCaputre.srvCounted = 1;
+ TraceServerFin(session->finCaputre.srvFinSeq, session->srvExpected);
+ }
+ }
+
+ if (session->flags.finCount >= 2)
+ RemoveSession(session, ipInfo, tcpInfo, 0);
+}
+
+
+/* Passes in an IP/TCP packet for decoding (ethernet/localhost frame) removed */
+/* returns Number of bytes on success, 0 for no data yet, and -1 on error */
+int ssl_DecodePacket(const byte* packet, int length, byte* data, char* error)
+{
+ TcpInfo tcpInfo;
+ IpInfo ipInfo;
+ const byte* sslFrame;
+ const byte* end = packet + length;
+ int sslBytes; /* ssl bytes unconsumed */
+ int ret;
+ SnifferSession* session = 0;
+
+ if (CheckHeaders(&ipInfo, &tcpInfo, packet, length, &sslFrame, &sslBytes,
+ error) != 0)
+ return -1;
+
+ ret = CheckSession(&ipInfo, &tcpInfo, sslBytes, &session, error);
+ if (ret == -1) return -1;
+ else if (ret == 1) return 0; /* done for now */
+
+ ret = CheckSequence(&ipInfo, &tcpInfo, session, &sslBytes, &sslFrame,error);
+ if (ret == -1) return -1;
+ else if (ret == 1) return 0; /* done for now */
+
+ ret = CheckPreRecord(&ipInfo, &tcpInfo, &sslFrame, session, &sslBytes,
+ &end, error);
+ if (ret == -1) return -1;
+ else if (ret == 1) return 0; /* done for now */
+
+ ret = ProcessMessage(&ipInfo, &tcpInfo, sslFrame, session, sslBytes, data,
+ end, error);
+ CheckFinCapture(&ipInfo, &tcpInfo, session);
+ return ret;
+}
+
+
+/* Enables (if traceFile)/ Disables debug tracing */
+/* returns 0 on success, -1 on error */
+int ssl_Trace(const char* traceFile, char* error)
+{
+ if (traceFile) {
+ TraceFile = fopen(traceFile, "a");
+ if (!TraceFile) {
+ SetError(BAD_TRACE_FILE_STR, error, NULL, 0);
+ return -1;
+ }
+ TraceOn = 1;
+ }
+ else
+ TraceOn = 0;
+
+ return 0;
+}
+
+
+
+
+#endif /* CYASSL_SNIFFER */
generated by cgit v1.2.3-54-g00ecf (git 2.44.0) at 2024-04-19 06:16:13 +0000