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app-layer-ftp.c
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app-layer-ftp.c
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/* Copyright (C) 2007-2017 Open Information Security Foundation
*
* You can copy, redistribute or modify this Program under the terms of
* the GNU General Public License version 2 as published by the Free
* Software Foundation.
*
* This program 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
* version 2 along with this program; if not, write to the Free Software
* Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA
* 02110-1301, USA.
*/
/**
* \file
*
* \author Pablo Rincon Crespo <[email protected]>
* \author Eric Leblond <[email protected]>
* \author Jeff Lucovsky <[email protected]>
*
* App Layer Parser for FTP
*/
#include "suricata-common.h"
#include "debug.h"
#include "decode.h"
#include "threads.h"
#include "util-print.h"
#include "util-pool.h"
#include "flow-util.h"
#include "flow-storage.h"
#include "detect-engine-state.h"
#include "stream-tcp-private.h"
#include "stream-tcp-reassemble.h"
#include "stream-tcp.h"
#include "stream.h"
#include "app-layer.h"
#include "app-layer-protos.h"
#include "app-layer-parser.h"
#include "app-layer-ftp.h"
#include "app-layer-expectation.h"
#include "util-spm.h"
#include "util-mpm.h"
#include "util-unittest.h"
#include "util-debug.h"
#include "util-memcmp.h"
#include "util-memrchr.h"
#include "util-byte.h"
#include "util-mem.h"
#include "util-misc.h"
#include "rust-ftp-mod-gen.h"
#include "output-json.h"
typedef struct FTPThreadCtx_ {
MpmThreadCtx *ftp_mpm_thread_ctx;
PrefilterRuleStore *pmq;
} FTPThreadCtx;
#define FTP_MPM mpm_default_matcher
static MpmCtx *ftp_mpm_ctx = NULL;
const FtpCommand FtpCommands[FTP_COMMAND_MAX + 1] = {
/* Parsed and handled */
{ FTP_COMMAND_PORT, "PORT", 4},
{ FTP_COMMAND_EPRT, "EPRT", 4},
{ FTP_COMMAND_AUTH_TLS, "AUTH TLS", 8},
{ FTP_COMMAND_PASV, "PASV", 4},
{ FTP_COMMAND_RETR, "RETR", 4},
{ FTP_COMMAND_EPSV, "EPSV", 4},
{ FTP_COMMAND_STOR, "STOR", 4},
/* Parsed, but not handled */
{ FTP_COMMAND_ABOR, "ABOR", 4},
{ FTP_COMMAND_ACCT, "ACCT", 4},
{ FTP_COMMAND_ALLO, "ALLO", 4},
{ FTP_COMMAND_APPE, "APPE", 4},
{ FTP_COMMAND_CDUP, "CDUP", 4},
{ FTP_COMMAND_CHMOD, "CHMOD", 5},
{ FTP_COMMAND_CWD, "CWD", 3},
{ FTP_COMMAND_DELE, "DELE", 4},
{ FTP_COMMAND_HELP, "HELP", 4},
{ FTP_COMMAND_IDLE, "IDLE", 4},
{ FTP_COMMAND_LIST, "LIST", 4},
{ FTP_COMMAND_MAIL, "MAIL", 4},
{ FTP_COMMAND_MDTM, "MDTM", 4},
{ FTP_COMMAND_MKD, "MKD", 3},
{ FTP_COMMAND_MLFL, "MLFL", 4},
{ FTP_COMMAND_MODE, "MODE", 4},
{ FTP_COMMAND_MRCP, "MRCP", 4},
{ FTP_COMMAND_MRSQ, "MRSQ", 4},
{ FTP_COMMAND_MSAM, "MSAM", 4},
{ FTP_COMMAND_MSND, "MSND", 4},
{ FTP_COMMAND_MSOM, "MSOM", 4},
{ FTP_COMMAND_NLST, "NLST", 4},
{ FTP_COMMAND_NOOP, "NOOP", 4},
{ FTP_COMMAND_PASS, "PASS", 4},
{ FTP_COMMAND_PWD, "PWD", 3},
{ FTP_COMMAND_QUIT, "QUIT", 4},
{ FTP_COMMAND_REIN, "REIN", 4},
{ FTP_COMMAND_REST, "REST", 4},
{ FTP_COMMAND_RMD, "RMD", 3},
{ FTP_COMMAND_RNFR, "RNFR", 4},
{ FTP_COMMAND_RNTO, "RNTO", 4},
{ FTP_COMMAND_SITE, "SITE", 4},
{ FTP_COMMAND_SIZE, "SIZE", 4},
{ FTP_COMMAND_SMNT, "SMNT", 4},
{ FTP_COMMAND_STAT, "STAT", 4},
{ FTP_COMMAND_STOU, "STOU", 4},
{ FTP_COMMAND_STRU, "STRU", 4},
{ FTP_COMMAND_SYST, "SYST", 4},
{ FTP_COMMAND_TYPE, "TYPE", 4},
{ FTP_COMMAND_UMASK, "UMASK", 5},
{ FTP_COMMAND_USER, "USER", 4},
{ FTP_COMMAND_UNKNOWN, NULL, 0}
};
uint64_t ftp_config_memcap = 0;
SC_ATOMIC_DECLARE(uint64_t, ftp_memuse);
SC_ATOMIC_DECLARE(uint64_t, ftp_memcap);
static FTPTransaction *FTPGetOldestTx(FtpState *);
static void FTPParseMemcap(void)
{
const char *conf_val;
/** set config values for memcap, prealloc and hash_size */
if ((ConfGet("app-layer.protocols.ftp.memcap", &conf_val)) == 1)
{
if (ParseSizeStringU64(conf_val, &ftp_config_memcap) < 0) {
SCLogError(SC_ERR_SIZE_PARSE, "Error parsing ftp.memcap "
"from conf file - %s. Killing engine",
conf_val);
exit(EXIT_FAILURE);
}
SCLogInfo("FTP memcap: %"PRIu64, ftp_config_memcap);
} else {
/* default to unlimited */
ftp_config_memcap = 0;
}
SC_ATOMIC_INIT(ftp_memuse);
SC_ATOMIC_INIT(ftp_memcap);
}
static void FTPIncrMemuse(uint64_t size)
{
(void) SC_ATOMIC_ADD(ftp_memuse, size);
return;
}
static void FTPDecrMemuse(uint64_t size)
{
(void) SC_ATOMIC_SUB(ftp_memuse, size);
return;
}
uint64_t FTPMemuseGlobalCounter(void)
{
uint64_t tmpval = SC_ATOMIC_GET(ftp_memuse);
return tmpval;
}
uint64_t FTPMemcapGlobalCounter(void)
{
uint64_t tmpval = SC_ATOMIC_GET(ftp_memcap);
return tmpval;
}
/**
* \brief Check if alloc'ing "size" would mean we're over memcap
*
* \retval 1 if in bounds
* \retval 0 if not in bounds
*/
static int FTPCheckMemcap(uint64_t size)
{
if (ftp_config_memcap == 0 || size + SC_ATOMIC_GET(ftp_memuse) <= ftp_config_memcap)
return 1;
(void) SC_ATOMIC_ADD(ftp_memcap, 1);
return 0;
}
static void *FTPMalloc(size_t size)
{
void *ptr = NULL;
if (FTPCheckMemcap((uint32_t)size) == 0)
return NULL;
ptr = SCMalloc(size);
if (unlikely(ptr == NULL))
return NULL;
FTPIncrMemuse((uint64_t)size);
return ptr;
}
static void *FTPCalloc(size_t n, size_t size)
{
void *ptr = NULL;
if (FTPCheckMemcap((uint32_t)(n * size)) == 0)
return NULL;
ptr = SCCalloc(n, size);
if (unlikely(ptr == NULL))
return NULL;
FTPIncrMemuse((uint64_t)(n * size));
return ptr;
}
static void *FTPRealloc(void *ptr, size_t orig_size, size_t size)
{
void *rptr = NULL;
if (FTPCheckMemcap((uint32_t)(size - orig_size)) == 0)
return NULL;
rptr = SCRealloc(ptr, size);
if (rptr == NULL)
return NULL;
if (size > orig_size) {
FTPIncrMemuse(size - orig_size);
} else {
FTPDecrMemuse(orig_size - size);
}
return rptr;
}
static void FTPFree(void *ptr, size_t size)
{
SCFree(ptr);
FTPDecrMemuse((uint64_t)size);
}
static FTPString *FTPStringAlloc(void)
{
return FTPCalloc(1, sizeof(FTPString));
}
static void FTPStringFree(FTPString *str)
{
if (str->str) {
FTPFree(str->str, str->len);
}
FTPFree(str, sizeof(FTPString));
}
static void *FTPLocalStorageAlloc(void)
{
/* needed by the mpm */
FTPThreadCtx *td = SCCalloc(1, sizeof(*td));
if (td == NULL) {
exit(EXIT_FAILURE);
}
td->pmq = SCCalloc(1, sizeof(*td->pmq));
if (td->pmq == NULL) {
exit(EXIT_FAILURE);
}
PmqSetup(td->pmq);
td->ftp_mpm_thread_ctx = SCCalloc(1, sizeof(MpmThreadCtx));
if (unlikely(td->ftp_mpm_thread_ctx == NULL)) {
exit(EXIT_FAILURE);
}
MpmInitThreadCtx(td->ftp_mpm_thread_ctx, FTP_MPM);
return td;
}
static void FTPLocalStorageFree(void *ptr)
{
FTPThreadCtx *td = ptr;
if (td != NULL) {
if (td->pmq != NULL) {
PmqFree(td->pmq);
SCFree(td->pmq);
}
if (td->ftp_mpm_thread_ctx != NULL) {
mpm_table[FTP_MPM].DestroyThreadCtx(ftp_mpm_ctx, td->ftp_mpm_thread_ctx);
SCFree(td->ftp_mpm_thread_ctx);
}
SCFree(td);
}
return;
}
static FTPTransaction *FTPTransactionCreate(FtpState *state)
{
SCEnter();
FTPTransaction *tx = FTPCalloc(1, sizeof(*tx));
if (tx == NULL) {
return NULL;
}
TAILQ_INSERT_TAIL(&state->tx_list, tx, next);
tx->tx_id = state->tx_cnt++;
TAILQ_INIT(&tx->response_list);
SCLogDebug("new transaction %p (state tx cnt %"PRIu64")", tx, state->tx_cnt);
return tx;
}
static void FTPTransactionFree(FTPTransaction *tx)
{
SCEnter();
if (tx->de_state != NULL) {
DetectEngineStateFree(tx->de_state);
}
if (tx->request) {
FTPFree(tx->request, tx->request_length);
}
FTPString *str = NULL;
while ((str = TAILQ_FIRST(&tx->response_list))) {
TAILQ_REMOVE(&tx->response_list, str, next);
FTPStringFree(str);
}
SCFree(tx);
}
static int FTPGetLineForDirection(FtpState *state, FtpLineState *line_state)
{
void *ptmp;
if (line_state->current_line_lf_seen == 1) {
/* we have seen the lf for the previous line. Clear the parser
* details to parse new line */
line_state->current_line_lf_seen = 0;
if (line_state->current_line_db == 1) {
line_state->current_line_db = 0;
FTPFree(line_state->db, line_state->db_len);
line_state->db = NULL;
line_state->db_len = 0;
state->current_line = NULL;
state->current_line_len = 0;
}
}
uint8_t *lf_idx = memchr(state->input, 0x0a, state->input_len);
if (lf_idx == NULL) {
/* fragmented lines. Decoder event for special cases. Not all
* fragmented lines should be treated as a possible evasion
* attempt. With multi payload ftp chunks we can have valid
* cases of fragmentation. But within the same segment chunk
* if we see fragmentation then it's definitely something you
* should alert about */
if (line_state->current_line_db == 0) {
line_state->db = FTPMalloc(state->input_len);
if (line_state->db == NULL) {
return -1;
}
line_state->current_line_db = 1;
memcpy(line_state->db, state->input, state->input_len);
line_state->db_len = state->input_len;
} else {
ptmp = FTPRealloc(line_state->db, line_state->db_len,
(line_state->db_len + state->input_len));
if (ptmp == NULL) {
FTPFree(line_state->db, line_state->db_len);
line_state->db = NULL;
line_state->db_len = 0;
return -1;
}
line_state->db = ptmp;
memcpy(line_state->db + line_state->db_len,
state->input, state->input_len);
line_state->db_len += state->input_len;
}
state->input += state->input_len;
state->input_len = 0;
return -1;
} else {
line_state->current_line_lf_seen = 1;
if (line_state->current_line_db == 1) {
ptmp = FTPRealloc(line_state->db, line_state->db_len,
(line_state->db_len + (lf_idx + 1 - state->input)));
if (ptmp == NULL) {
FTPFree(line_state->db, line_state->db_len);
line_state->db = NULL;
line_state->db_len = 0;
return -1;
}
line_state->db = ptmp;
memcpy(line_state->db + line_state->db_len,
state->input, (lf_idx + 1 - state->input));
line_state->db_len += (lf_idx + 1 - state->input);
if (line_state->db_len > 1 &&
line_state->db[line_state->db_len - 2] == 0x0D) {
line_state->db_len -= 2;
state->current_line_delimiter_len = 2;
} else {
line_state->db_len -= 1;
state->current_line_delimiter_len = 1;
}
state->current_line = line_state->db;
state->current_line_len = line_state->db_len;
} else {
state->current_line = state->input;
state->current_line_len = lf_idx - state->input;
if (state->input != lf_idx &&
*(lf_idx - 1) == 0x0D) {
state->current_line_len--;
state->current_line_delimiter_len = 2;
} else {
state->current_line_delimiter_len = 1;
}
}
state->input_len -= (lf_idx - state->input) + 1;
state->input = (lf_idx + 1);
return 0;
}
}
static int FTPGetLine(FtpState *state)
{
SCEnter();
/* we have run out of input */
if (state->input_len <= 0)
return -1;
/* toserver */
if (state->direction == 0)
return FTPGetLineForDirection(state, &state->line_state[0]);
else
return FTPGetLineForDirection(state, &state->line_state[1]);
}
/**
* \brief This function is called to determine and set which command is being
* transferred to the ftp server
* \param thread context
* \param input input line of the command
* \param len of the command
* \param cmd_descriptor when the command has been parsed
*
* \retval 1 when the command is parsed, 0 otherwise
*/
static int FTPParseRequestCommand(FTPThreadCtx *td,
const uint8_t *input, uint32_t input_len,
const FtpCommand **cmd_descriptor)
{
SCEnter();
/* I don't like this pmq reset here. We'll devise a method later, that
* should make the use of the mpm very efficient */
PmqReset(td->pmq);
int mpm_cnt = mpm_table[FTP_MPM].Search(ftp_mpm_ctx, td->ftp_mpm_thread_ctx,
td->pmq, input, input_len);
if (mpm_cnt) {
*cmd_descriptor = &FtpCommands[td->pmq->rule_id_array[0]];
SCReturnInt(1);
}
*cmd_descriptor = NULL;
SCReturnInt(0);
}
struct FtpTransferCmd {
/** Need to look like a ExpectationData so DFree must
* be first field . */
void (*DFree)(void *);
uint64_t flow_id;
uint8_t *file_name;
uint16_t file_len;
FtpRequestCommand cmd;
};
static void FtpTransferCmdFree(void *data)
{
struct FtpTransferCmd *cmd = (struct FtpTransferCmd *) data;
if (cmd == NULL)
return;
if (cmd->file_name) {
FTPFree(cmd->file_name, cmd->file_len);
}
FTPFree(cmd, sizeof(struct FtpTransferCmd));
}
static uint32_t CopyCommandLine(uint8_t **dest, const uint8_t *src, uint32_t length)
{
if (likely(length)) {
uint8_t *where = FTPCalloc(length + 1, sizeof(char));
if (unlikely(where == NULL)) {
return 0;
}
memcpy(where, src, length);
/* Remove trailing newlines/carriage returns */
while (length && isspace((unsigned char) where[length - 1])) {
length--;
}
where[length] = '\0';
*dest = where;
}
/* either 0 or actual */
return length;
}
/**
* \brief This function is called to retrieve a ftp request
* \param ftp_state the ftp state structure for the parser
* \param input input line of the command
* \param input_len length of the request
* \param output the resulting output
*
* \retval 1 when the command is parsed, 0 otherwise
*/
static int FTPParseRequest(Flow *f, void *ftp_state,
AppLayerParserState *pstate,
const uint8_t *input, uint32_t input_len,
void *local_data, const uint8_t flags)
{
FTPThreadCtx *thread_data = local_data;
SCEnter();
/* PrintRawDataFp(stdout, input,input_len); */
FtpState *state = (FtpState *)ftp_state;
void *ptmp;
if (input == NULL && AppLayerParserStateIssetFlag(pstate, APP_LAYER_PARSER_EOF)) {
SCReturnInt(1);
} else if (input == NULL || input_len == 0) {
SCReturnInt(-1);
}
state->input = input;
state->input_len = input_len;
/* toserver stream */
state->direction = 0;
int direction = STREAM_TOSERVER;
while (FTPGetLine(state) >= 0) {
const FtpCommand *cmd_descriptor;
if (!FTPParseRequestCommand(thread_data, state->current_line, state->current_line_len, &cmd_descriptor)) {
state->command = FTP_COMMAND_UNKNOWN;
continue;
}
state->command = cmd_descriptor->command;
FTPTransaction *tx = FTPTransactionCreate(state);
if (unlikely(tx == NULL))
return -1;
state->curr_tx = tx;
tx->command_descriptor = cmd_descriptor;
tx->request_length = CopyCommandLine(&tx->request, state->current_line, state->current_line_len);
switch (state->command) {
case FTP_COMMAND_EPRT:
// fallthrough
case FTP_COMMAND_PORT:
if (state->current_line_len + 1 > state->port_line_size) {
/* Allocate an extra byte for a NULL terminator */
ptmp = FTPRealloc(state->port_line, state->port_line_size,
state->current_line_len);
if (ptmp == NULL) {
if (state->port_line) {
FTPFree(state->port_line, state->port_line_size);
state->port_line = NULL;
state->port_line_size = 0;
}
return 0;
}
state->port_line = ptmp;
state->port_line_size = state->current_line_len;
}
memcpy(state->port_line, state->current_line,
state->current_line_len);
state->port_line_len = state->current_line_len;
break;
case FTP_COMMAND_RETR:
/* change direction (default to server) so expectation will handle
* the correct message when expectation will match.
*/
direction = STREAM_TOCLIENT;
// fallthrough
case FTP_COMMAND_STOR:
{
/* No dyn port negotiated so get out */
if (state->dyn_port == 0) {
SCReturnInt(-1);
}
struct FtpTransferCmd *data = FTPCalloc(1, sizeof(struct FtpTransferCmd));
if (data == NULL)
SCReturnInt(-1);
data->DFree = FtpTransferCmdFree;
/* Min size has been checked in FTPParseRequestCommand */
data->file_name = FTPCalloc(state->current_line_len - 4, sizeof(char));
if (data->file_name == NULL) {
FtpTransferCmdFree(data);
SCReturnInt(-1);
}
data->file_name[state->current_line_len - 5] = 0;
data->file_len = state->current_line_len - 5;
memcpy(data->file_name, state->current_line + 5, state->current_line_len - 5);
data->cmd = state->command;
data->flow_id = FlowGetId(f);
int ret = AppLayerExpectationCreate(f,
state->active ? STREAM_TOSERVER : direction,
0, state->dyn_port, ALPROTO_FTPDATA, data);
if (ret == -1) {
FtpTransferCmdFree(data);
SCLogDebug("No expectation created.");
SCReturnInt(-1);
} else {
SCLogDebug("Expectation created [direction: %s, dynamic port %"PRIu16"].",
state->active ? "to server" : "to client",
state->dyn_port);
}
/* reset the dyn port to avoid duplicate */
state->dyn_port = 0;
/* reset active/passive indicator */
state->active = false;
}
break;
default:
break;
}
}
return 1;
}
static int FTPParsePassiveResponse(Flow *f, FtpState *state, const uint8_t *input, uint32_t input_len)
{
uint16_t dyn_port = rs_ftp_pasv_response(input, input_len);
if (dyn_port == 0) {
return -1;
}
SCLogDebug("FTP passive mode (v4): dynamic port %"PRIu16"", dyn_port);
state->active = false;
state->dyn_port = dyn_port;
state->curr_tx->dyn_port = dyn_port;
state->curr_tx->active = false;
return 0;
}
static int FTPParsePassiveResponseV6(Flow *f, FtpState *state, const uint8_t *input, uint32_t input_len)
{
uint16_t dyn_port = rs_ftp_epsv_response(input, input_len);
if (dyn_port == 0) {
return -1;
}
SCLogDebug("FTP passive mode (v6): dynamic port %"PRIu16"", dyn_port);
state->active = false;
state->dyn_port = dyn_port;
state->curr_tx->dyn_port = dyn_port;
state->curr_tx->active = false;
return 0;
}
/**
* \brief Handle preliminary replies -- keep tx open
* \retval: True for a positive preliminary reply; false otherwise
*
* 1yz Positive Preliminary reply
*
* The requested action is being initiated; expect another
* reply before proceeding with a new command
*/
static inline bool FTPIsPPR(const uint8_t *input, uint32_t input_len)
{
return input_len >= 4 && isdigit(input[0]) && input[0] == '1' &&
isdigit(input[1]) && isdigit(input[2]) && isspace(input[3]);
}
/**
* \brief This function is called to retrieve a ftp response
* \param ftp_state the ftp state structure for the parser
* \param input input line of the command
* \param input_len length of the request
* \param output the resulting output
*
* \retval 1 when the command is parsed, 0 otherwise
*/
static int FTPParseResponse(Flow *f, void *ftp_state, AppLayerParserState *pstate,
const uint8_t *input, uint32_t input_len,
void *local_data, const uint8_t flags)
{
FtpState *state = (FtpState *)ftp_state;
int retcode = 1;
if (unlikely(input_len == 0)) {
return 1;
}
FTPTransaction *tx = FTPGetOldestTx(state);
if (tx == NULL) {
tx = FTPTransactionCreate(state);
}
if (unlikely(tx == NULL)) {
return -1;
}
if (state->command == FTP_COMMAND_UNKNOWN || tx->command_descriptor == NULL) {
/* unknown */
tx->command_descriptor = &FtpCommands[FTP_COMMAND_MAX -1];
}
state->curr_tx = tx;
if (state->command == FTP_COMMAND_AUTH_TLS) {
if (input_len >= 4 && SCMemcmp("234 ", input, 4) == 0) {
AppLayerRequestProtocolTLSUpgrade(f);
}
}
if (state->command == FTP_COMMAND_EPRT) {
uint16_t dyn_port = rs_ftp_active_eprt(state->port_line, state->port_line_len);
if (dyn_port == 0) {
retcode = 0;
goto tx_complete;
}
state->dyn_port = dyn_port;
state->active = true;
tx->dyn_port = dyn_port;
tx->active = true;
SCLogDebug("FTP active mode (v6): dynamic port %"PRIu16"", dyn_port);
}
if (state->command == FTP_COMMAND_PORT) {
if ((flags & STREAM_TOCLIENT)) {
uint16_t dyn_port = rs_ftp_active_port(state->port_line, state->port_line_len);
if (dyn_port == 0) {
retcode = 0;
goto tx_complete;
}
state->dyn_port = dyn_port;
state->active = true;
tx->dyn_port = state->dyn_port;
tx->active = true;
SCLogDebug("FTP active mode (v4): dynamic port %"PRIu16"", dyn_port);
}
}
if (state->command == FTP_COMMAND_PASV) {
if (input_len >= 4 && SCMemcmp("227 ", input, 4) == 0) {
FTPParsePassiveResponse(f, ftp_state, input, input_len);
}
}
if (state->command == FTP_COMMAND_EPSV) {
if (input_len >= 4 && SCMemcmp("229 ", input, 4) == 0) {
FTPParsePassiveResponseV6(f, ftp_state, input, input_len);
}
}
if (likely(input_len)) {
FTPString *response = FTPStringAlloc();
if (likely(response)) {
response->len = CopyCommandLine(&response->str, input, input_len);
TAILQ_INSERT_TAIL(&tx->response_list, response, next);
}
}
/* Handle preliminary replies -- keep tx open */
if (FTPIsPPR(input, input_len)) {
return retcode;
}
tx_complete:
tx->done = true;
return retcode;
}
#ifdef DEBUG
static SCMutex ftp_state_mem_lock = SCMUTEX_INITIALIZER;
static uint64_t ftp_state_memuse = 0;
static uint64_t ftp_state_memcnt = 0;
#endif
static void *FTPStateAlloc(void)
{
void *s = FTPCalloc(1, sizeof(FtpState));
if (unlikely(s == NULL))
return NULL;
FtpState *ftp_state = (FtpState *) s;
TAILQ_INIT(&ftp_state->tx_list);
#ifdef DEBUG
SCMutexLock(&ftp_state_mem_lock);
ftp_state_memcnt++;
ftp_state_memuse+=sizeof(FtpState);
SCMutexUnlock(&ftp_state_mem_lock);
#endif
return s;
}
static void FTPStateFree(void *s)
{
FtpState *fstate = (FtpState *) s;
if (fstate->port_line != NULL)
FTPFree(fstate->port_line, fstate->port_line_size);
if (fstate->line_state[0].db)
FTPFree(fstate->line_state[0].db, fstate->line_state[0].db_len);
if (fstate->line_state[1].db)
FTPFree(fstate->line_state[1].db, fstate->line_state[1].db_len);
//AppLayerDecoderEventsFreeEvents(&s->decoder_events);
FTPTransaction *tx = NULL;
while ((tx = TAILQ_FIRST(&fstate->tx_list))) {
TAILQ_REMOVE(&fstate->tx_list, tx, next);
SCLogDebug("[%s] state %p id %"PRIu64", Freeing %d bytes at %p",
tx->command_descriptor->command_name,
s, tx->tx_id,
tx->request_length, tx->request);
FTPTransactionFree(tx);
}
FTPFree(s, sizeof(FtpState));
#ifdef DEBUG
SCMutexLock(&ftp_state_mem_lock);
ftp_state_memcnt--;
ftp_state_memuse-=sizeof(FtpState);
SCMutexUnlock(&ftp_state_mem_lock);
#endif
}
static int FTPSetTxDetectState(void *vtx, DetectEngineState *de_state)
{
FTPTransaction *tx = (FTPTransaction *)vtx;
tx->de_state = de_state;
return 0;
}
/**
* \brief This function returns the oldest open transaction; if none
* are open, then the oldest transaction is returned
* \param ftp_state the ftp state structure for the parser
*
* \retval transaction pointer when a transaction was found; NULL otherwise.
*/
static FTPTransaction *FTPGetOldestTx(FtpState *ftp_state)
{
if (unlikely(!ftp_state)) {
SCLogDebug("NULL state object; no transactions available");
return NULL;
}
FTPTransaction *tx = NULL;
FTPTransaction *lasttx = NULL;
TAILQ_FOREACH(tx, &ftp_state->tx_list, next) {
/* Return oldest open tx */
if (!tx->done) {
SCLogDebug("Returning tx %p id %"PRIu64, tx, tx->tx_id);
return tx;
}
/* save for the end */
lasttx = tx;
}
/* All tx are closed; return last element */
if (lasttx)
SCLogDebug("Returning OLDEST tx %p id %"PRIu64, lasttx, lasttx->tx_id);
return lasttx;
}
static void *FTPGetTx(void *state, uint64_t tx_id)
{
FtpState *ftp_state = (FtpState *)state;
if (ftp_state) {
FTPTransaction *tx = NULL;
if (ftp_state->curr_tx == NULL)
return NULL;
if (ftp_state->curr_tx->tx_id == tx_id)
return ftp_state->curr_tx;
TAILQ_FOREACH(tx, &ftp_state->tx_list, next) {
if (tx->tx_id == tx_id)
return tx;
}
}
return NULL;
}
static DetectEngineState *FTPGetTxDetectState(void *vtx)
{
FTPTransaction *tx = (FTPTransaction *)vtx;
return tx->de_state;
}
static uint64_t FTPGetTxDetectFlags(void *vtx, uint8_t dir)
{
FTPTransaction *tx = (FTPTransaction *)vtx;
if (dir & STREAM_TOSERVER) {
return tx->detect_flags_ts;
} else {
return tx->detect_flags_tc;
}
}
static void FTPSetTxDetectFlags(void *vtx, uint8_t dir, uint64_t flags)
{
FTPTransaction *tx = (FTPTransaction *)vtx;
if (dir & STREAM_TOSERVER) {
tx->detect_flags_ts = flags;
} else {
tx->detect_flags_tc = flags;
}
}
static void FTPStateTransactionFree(void *state, uint64_t tx_id)
{
FtpState *ftp_state = state;
FTPTransaction *tx = NULL;
TAILQ_FOREACH(tx, &ftp_state->tx_list, next) {
if (tx_id < tx->tx_id)
break;
else if (tx_id > tx->tx_id)
continue;
if (tx == ftp_state->curr_tx)
ftp_state->curr_tx = NULL;
TAILQ_REMOVE(&ftp_state->tx_list, tx, next);
FTPTransactionFree(tx);
break;
}
}
static uint64_t FTPGetTxCnt(void *state)
{
uint64_t cnt = 0;
FtpState *ftp_state = state;
if (ftp_state) {
cnt = ftp_state->tx_cnt;
}
SCLogDebug("returning state %p %"PRIu64, state, cnt);
return cnt;
}
static int FTPGetAlstateProgressCompletionStatus(uint8_t direction)
{
return FTP_STATE_FINISHED;
}
static int FTPGetAlstateProgress(void *vtx, uint8_t direction)
{
SCLogDebug("tx %p", vtx);
FTPTransaction *tx = vtx;
if (direction == STREAM_TOSERVER &&
tx->command_descriptor->command == FTP_COMMAND_PORT) {
return FTP_STATE_PORT_DONE;
}
if (!tx->done)
return FTP_STATE_IN_PROGRESS;
return FTP_STATE_FINISHED;