| 1 | /* $NetBSD: ip_ftp_pxy.c,v 1.6 2016/10/16 05:11:34 mrg Exp $ */ |
| 2 | |
| 3 | /* |
| 4 | * Copyright (C) 2012 by Darren Reed. |
| 5 | * |
| 6 | * See the IPFILTER.LICENCE file for details on licencing. |
| 7 | * |
| 8 | * Simple FTP transparent proxy for in-kernel use. For use with the NAT |
| 9 | * code. |
| 10 | * |
| 11 | * Id: ip_ftp_pxy.c,v 1.1.1.2 2012/07/22 13:45:18 darrenr Exp |
| 12 | */ |
| 13 | |
| 14 | #include <sys/cdefs.h> |
| 15 | __KERNEL_RCSID(1, "$NetBSD: ip_ftp_pxy.c,v 1.6 2016/10/16 05:11:34 mrg Exp $" ); |
| 16 | |
| 17 | #define IPF_FTP_PROXY |
| 18 | |
| 19 | #define IPF_MINPORTLEN 18 |
| 20 | #define IPF_MINEPRTLEN 20 |
| 21 | #define IPF_MAXPORTLEN 30 |
| 22 | #define IPF_MIN227LEN 39 |
| 23 | #define IPF_MAX227LEN 51 |
| 24 | #define IPF_MIN229LEN 47 |
| 25 | #define IPF_MAX229LEN 51 |
| 26 | |
| 27 | #define FTPXY_GO 0 |
| 28 | #define FTPXY_INIT 1 |
| 29 | #define FTPXY_USER_1 2 |
| 30 | #define FTPXY_USOK_1 3 |
| 31 | #define FTPXY_PASS_1 4 |
| 32 | #define FTPXY_PAOK_1 5 |
| 33 | #define FTPXY_AUTH_1 6 |
| 34 | #define FTPXY_AUOK_1 7 |
| 35 | #define FTPXY_ADAT_1 8 |
| 36 | #define FTPXY_ADOK_1 9 |
| 37 | #define FTPXY_ACCT_1 10 |
| 38 | #define FTPXY_ACOK_1 11 |
| 39 | #define FTPXY_USER_2 12 |
| 40 | #define FTPXY_USOK_2 13 |
| 41 | #define FTPXY_PASS_2 14 |
| 42 | #define FTPXY_PAOK_2 15 |
| 43 | |
| 44 | #define FTPXY_JUNK_OK 0 |
| 45 | #define FTPXY_JUNK_BAD 1 /* Ignore all commands for this connection */ |
| 46 | #define FTPXY_JUNK_EOL 2 /* consume the rest of this line only */ |
| 47 | #define FTPXY_JUNK_CONT 3 /* Saerching for next numeric */ |
| 48 | |
| 49 | /* |
| 50 | * Values for FTP commands. Numerics cover 0-999 |
| 51 | */ |
| 52 | #define FTPXY_C_PASV 1000 |
| 53 | #define FTPXY_C_PORT 1001 |
| 54 | #define FTPXY_C_EPSV 1002 |
| 55 | #define FTPXY_C_EPRT 1003 |
| 56 | |
| 57 | |
| 58 | typedef struct ipf_ftp_softc_s { |
| 59 | int ipf_p_ftp_pasvonly; |
| 60 | /* Do not require logins before transfers */ |
| 61 | int ipf_p_ftp_insecure; |
| 62 | int ipf_p_ftp_pasvrdr; |
| 63 | /* PASV must be last command prior to 227 */ |
| 64 | int ipf_p_ftp_forcepasv; |
| 65 | int ipf_p_ftp_debug; |
| 66 | int ipf_p_ftp_single_xfer; |
| 67 | void *ipf_p_ftp_tune; |
| 68 | } ipf_ftp_softc_t; |
| 69 | |
| 70 | |
| 71 | void ipf_p_ftp_main_load(void); |
| 72 | void ipf_p_ftp_main_unload(void); |
| 73 | void *ipf_p_ftp_soft_create(ipf_main_softc_t *); |
| 74 | void ipf_p_ftp_soft_destroy(ipf_main_softc_t *, void *); |
| 75 | |
| 76 | int ipf_p_ftp_client(ipf_ftp_softc_t *, fr_info_t *, ip_t *, nat_t *, |
| 77 | ftpinfo_t *, int); |
| 78 | int ipf_p_ftp_complete(char *, size_t); |
| 79 | int ipf_p_ftp_in(void *, fr_info_t *, ap_session_t *, nat_t *); |
| 80 | int ipf_p_ftp_new(void *, fr_info_t *, ap_session_t *, nat_t *); |
| 81 | void ipf_p_ftp_del(ipf_main_softc_t *, ap_session_t *); |
| 82 | int ipf_p_ftp_out(void *, fr_info_t *, ap_session_t *, nat_t *); |
| 83 | int ipf_p_ftp_pasv(ipf_ftp_softc_t *, fr_info_t *, ip_t *, nat_t *, |
| 84 | ftpinfo_t *, int); |
| 85 | int ipf_p_ftp_epsv(ipf_ftp_softc_t *, fr_info_t *, ip_t *, nat_t *, |
| 86 | ftpinfo_t *, int); |
| 87 | int ipf_p_ftp_port(ipf_ftp_softc_t *, fr_info_t *, ip_t *, nat_t *, |
| 88 | ftpinfo_t *, int); |
| 89 | int ipf_p_ftp_process(ipf_ftp_softc_t *, fr_info_t *, nat_t *, |
| 90 | ftpinfo_t *, int); |
| 91 | int ipf_p_ftp_server(ipf_ftp_softc_t *, fr_info_t *, ip_t *, nat_t *, |
| 92 | ftpinfo_t *, int); |
| 93 | int ipf_p_ftp_valid(ipf_ftp_softc_t *, ftpinfo_t *, int, char *, size_t); |
| 94 | int ipf_p_ftp_server_valid(ipf_ftp_softc_t *, ftpside_t *, char *, |
| 95 | size_t); |
| 96 | int ipf_p_ftp_client_valid(ipf_ftp_softc_t *, ftpside_t *, char *, |
| 97 | size_t); |
| 98 | u_short ipf_p_ftp_atoi(char **); |
| 99 | int ipf_p_ftp_pasvreply(ipf_ftp_softc_t *, fr_info_t *, ip_t *, nat_t *, |
| 100 | ftpinfo_t *, u_int, char *, char *); |
| 101 | int ipf_p_ftp_eprt(ipf_ftp_softc_t *, fr_info_t *, ip_t *, nat_t *, |
| 102 | ftpinfo_t *, int); |
| 103 | int ipf_p_ftp_eprt4(ipf_ftp_softc_t *, fr_info_t *, ip_t *, nat_t *, |
| 104 | ftpinfo_t *, int); |
| 105 | int ipf_p_ftp_eprt6(ipf_ftp_softc_t *, fr_info_t *, ip_t *, nat_t *, |
| 106 | ftpinfo_t *, int); |
| 107 | int ipf_p_ftp_addport(ipf_ftp_softc_t *, fr_info_t *, ip_t *, nat_t *, |
| 108 | ftpinfo_t *, int, int, int); |
| 109 | void ipf_p_ftp_setpending(ipf_main_softc_t *, ftpinfo_t *); |
| 110 | |
| 111 | /* |
| 112 | * Debug levels |
| 113 | */ |
| 114 | #define DEBUG_SECURITY 0x01 |
| 115 | #define DEBUG_ERROR 0x02 |
| 116 | #define DEBUG_INFO 0x04 |
| 117 | #define DEBUG_PARSE_ERR 0x08 |
| 118 | #define DEBUG_PARSE_INFO 0x10 |
| 119 | #define DEBUG_PARSE 0x20 |
| 120 | |
| 121 | static int ipf_p_ftp_proxy_init = 0; |
| 122 | static frentry_t ftppxyfr; |
| 123 | static ipftuneable_t ipf_ftp_tuneables[] = { |
| 124 | { { (void *)offsetof(ipf_ftp_softc_t, ipf_p_ftp_debug) }, |
| 125 | "ftp_debug" , 0, 0x7f, |
| 126 | stsizeof(ipf_ftp_softc_t, ipf_p_ftp_debug), |
| 127 | 0, NULL, NULL }, |
| 128 | { { (void *)offsetof(ipf_ftp_softc_t, ipf_p_ftp_pasvonly) }, |
| 129 | "ftp_pasvonly" , 0, 1, |
| 130 | stsizeof(ipf_ftp_softc_t, ipf_p_ftp_pasvonly), |
| 131 | 0, NULL, NULL }, |
| 132 | { { (void *)offsetof(ipf_ftp_softc_t, ipf_p_ftp_insecure) }, |
| 133 | "ftp_insecure" , 0, 1, |
| 134 | stsizeof(ipf_ftp_softc_t, ipf_p_ftp_insecure), |
| 135 | 0, NULL, NULL }, |
| 136 | { { (void *)offsetof(ipf_ftp_softc_t, ipf_p_ftp_pasvrdr) }, |
| 137 | "ftp_pasvrdr" , 0, 1, |
| 138 | stsizeof(ipf_ftp_softc_t, ipf_p_ftp_pasvrdr), |
| 139 | 0, NULL, NULL }, |
| 140 | { { (void *)offsetof(ipf_ftp_softc_t, ipf_p_ftp_forcepasv) }, |
| 141 | "ftp_forcepasv" , 0, 1, |
| 142 | stsizeof(ipf_ftp_softc_t, ipf_p_ftp_forcepasv), |
| 143 | 0, NULL, NULL }, |
| 144 | { { (void *)offsetof(ipf_ftp_softc_t, ipf_p_ftp_single_xfer) }, |
| 145 | "ftp_single_xfer" , 0, 1, |
| 146 | stsizeof(ipf_ftp_softc_t, ipf_p_ftp_single_xfer), |
| 147 | 0, NULL, NULL }, |
| 148 | { { NULL }, NULL, 0, 0, 0, 0, NULL, NULL } |
| 149 | }; |
| 150 | |
| 151 | |
| 152 | void |
| 153 | ipf_p_ftp_main_load(void) |
| 154 | { |
| 155 | bzero((char *)&ftppxyfr, sizeof(ftppxyfr)); |
| 156 | ftppxyfr.fr_ref = 1; |
| 157 | ftppxyfr.fr_flags = FR_INQUE|FR_PASS|FR_QUICK|FR_KEEPSTATE; |
| 158 | |
| 159 | MUTEX_INIT(&ftppxyfr.fr_lock, "FTP Proxy Mutex" ); |
| 160 | ipf_p_ftp_proxy_init = 1; |
| 161 | } |
| 162 | |
| 163 | |
| 164 | void |
| 165 | ipf_p_ftp_main_unload(void) |
| 166 | { |
| 167 | |
| 168 | if (ipf_p_ftp_proxy_init == 1) { |
| 169 | MUTEX_DESTROY(&ftppxyfr.fr_lock); |
| 170 | ipf_p_ftp_proxy_init = 0; |
| 171 | } |
| 172 | } |
| 173 | |
| 174 | |
| 175 | /* |
| 176 | * Initialize local structures. |
| 177 | */ |
| 178 | void * |
| 179 | ipf_p_ftp_soft_create(ipf_main_softc_t *softc) |
| 180 | { |
| 181 | ipf_ftp_softc_t *softf; |
| 182 | |
| 183 | KMALLOC(softf, ipf_ftp_softc_t *); |
| 184 | if (softf == NULL) |
| 185 | return NULL; |
| 186 | |
| 187 | bzero((char *)softf, sizeof(*softf)); |
| 188 | #if defined(_KERNEL) |
| 189 | softf->ipf_p_ftp_debug = 0; |
| 190 | #else |
| 191 | softf->ipf_p_ftp_debug = DEBUG_PARSE_ERR; |
| 192 | #endif |
| 193 | softf->ipf_p_ftp_forcepasv = 1; |
| 194 | |
| 195 | softf->ipf_p_ftp_tune = ipf_tune_array_copy(softf, |
| 196 | sizeof(ipf_ftp_tuneables), |
| 197 | ipf_ftp_tuneables); |
| 198 | if (softf->ipf_p_ftp_tune == NULL) { |
| 199 | ipf_p_ftp_soft_destroy(softc, softf); |
| 200 | return NULL; |
| 201 | } |
| 202 | if (ipf_tune_array_link(softc, softf->ipf_p_ftp_tune) == -1) { |
| 203 | ipf_p_ftp_soft_destroy(softc, softf); |
| 204 | return NULL; |
| 205 | } |
| 206 | |
| 207 | return softf; |
| 208 | } |
| 209 | |
| 210 | |
| 211 | void |
| 212 | ipf_p_ftp_soft_destroy(ipf_main_softc_t *softc, void *arg) |
| 213 | { |
| 214 | ipf_ftp_softc_t *softf = arg; |
| 215 | |
| 216 | if (softf->ipf_p_ftp_tune != NULL) { |
| 217 | ipf_tune_array_unlink(softc, softf->ipf_p_ftp_tune); |
| 218 | KFREES(softf->ipf_p_ftp_tune, sizeof(ipf_ftp_tuneables)); |
| 219 | softf->ipf_p_ftp_tune = NULL; |
| 220 | } |
| 221 | |
| 222 | KFREE(softf); |
| 223 | } |
| 224 | |
| 225 | |
| 226 | int |
| 227 | ipf_p_ftp_new(void *arg, fr_info_t *fin, ap_session_t *aps, nat_t *nat) |
| 228 | { |
| 229 | ftpinfo_t *ftp; |
| 230 | ftpside_t *f; |
| 231 | |
| 232 | KMALLOC(ftp, ftpinfo_t *); |
| 233 | if (ftp == NULL) |
| 234 | return -1; |
| 235 | |
| 236 | nat = nat; /* LINT */ |
| 237 | |
| 238 | aps->aps_data = ftp; |
| 239 | aps->aps_psiz = sizeof(ftpinfo_t); |
| 240 | aps->aps_sport = htons(fin->fin_sport); |
| 241 | aps->aps_dport = htons(fin->fin_dport); |
| 242 | |
| 243 | bzero((char *)ftp, sizeof(*ftp)); |
| 244 | f = &ftp->ftp_side[0]; |
| 245 | f->ftps_rptr = f->ftps_buf; |
| 246 | f->ftps_wptr = f->ftps_buf; |
| 247 | f = &ftp->ftp_side[1]; |
| 248 | f->ftps_rptr = f->ftps_buf; |
| 249 | f->ftps_wptr = f->ftps_buf; |
| 250 | ftp->ftp_passok = FTPXY_INIT; |
| 251 | ftp->ftp_incok = 0; |
| 252 | return 0; |
| 253 | } |
| 254 | |
| 255 | |
| 256 | void |
| 257 | ipf_p_ftp_setpending(ipf_main_softc_t *softc, ftpinfo_t *ftp) |
| 258 | { |
| 259 | if (ftp->ftp_pendnat != NULL) |
| 260 | ipf_nat_setpending(softc, ftp->ftp_pendnat); |
| 261 | |
| 262 | if (ftp->ftp_pendstate != NULL) { |
| 263 | READ_ENTER(&softc->ipf_state); |
| 264 | ipf_state_setpending(softc, ftp->ftp_pendstate); |
| 265 | RWLOCK_EXIT(&softc->ipf_state); |
| 266 | } |
| 267 | } |
| 268 | |
| 269 | |
| 270 | void |
| 271 | ipf_p_ftp_del(ipf_main_softc_t *softc, ap_session_t *aps) |
| 272 | { |
| 273 | ftpinfo_t *ftp; |
| 274 | |
| 275 | ftp = aps->aps_data; |
| 276 | if (ftp != NULL) |
| 277 | ipf_p_ftp_setpending(softc, ftp); |
| 278 | } |
| 279 | |
| 280 | |
| 281 | int |
| 282 | ipf_p_ftp_port(ipf_ftp_softc_t *softf, fr_info_t *fin, ip_t *ip, nat_t *nat, |
| 283 | ftpinfo_t *ftp, int dlen) |
| 284 | { |
| 285 | char newbuf[IPF_FTPBUFSZ], *s; |
| 286 | u_int a1, a2, a3, a4; |
| 287 | u_short a5, a6, sp; |
| 288 | size_t nlen, olen; |
| 289 | tcphdr_t *tcp; |
| 290 | int inc, off; |
| 291 | ftpside_t *f; |
| 292 | mb_t *m; |
| 293 | |
| 294 | m = fin->fin_m; |
| 295 | f = &ftp->ftp_side[0]; |
| 296 | tcp = (tcphdr_t *)fin->fin_dp; |
| 297 | off = (char *)tcp - (char *)ip + (TCP_OFF(tcp) << 2) + fin->fin_ipoff; |
| 298 | |
| 299 | /* |
| 300 | * Check for client sending out PORT message. |
| 301 | */ |
| 302 | if (dlen < IPF_MINPORTLEN) { |
| 303 | DT3(ftp_PORT_error_dlen, nat_t *, nat, ftpside_t *, f, |
| 304 | u_int, dlen); |
| 305 | if (softf->ipf_p_ftp_debug & DEBUG_PARSE) |
| 306 | printf("ipf_p_ftp_port:dlen(%d) < IPF_MINPORTLEN\n" , |
| 307 | dlen); |
| 308 | return 0; |
| 309 | } |
| 310 | /* |
| 311 | * Skip the PORT command + space |
| 312 | */ |
| 313 | s = f->ftps_rptr + 5; |
| 314 | /* |
| 315 | * Pick out the address components, two at a time. |
| 316 | */ |
| 317 | a1 = ipf_p_ftp_atoi(&s); |
| 318 | if (s == NULL) { |
| 319 | DT2(ftp_PORT_error_atoi_1, nat_t *, nat, ftpside_t *, f); |
| 320 | if (softf->ipf_p_ftp_debug & DEBUG_PARSE_ERR) |
| 321 | printf("ipf_p_ftp_port:ipf_p_ftp_atoi(%d) failed\n" , 1); |
| 322 | return 0; |
| 323 | } |
| 324 | a2 = ipf_p_ftp_atoi(&s); |
| 325 | if (s == NULL) { |
| 326 | DT2(ftp_PORT_error_atoi_2, nat_t *, nat, ftpside_t *, f); |
| 327 | if (softf->ipf_p_ftp_debug & DEBUG_PARSE_ERR) |
| 328 | printf("ipf_p_ftp_port:ipf_p_ftp_atoi(%d) failed\n" , 2); |
| 329 | return 0; |
| 330 | } |
| 331 | |
| 332 | /* |
| 333 | * Check that IP address in the PORT/PASV reply is the same as the |
| 334 | * sender of the command - prevents using PORT for port scanning. |
| 335 | */ |
| 336 | a1 <<= 16; |
| 337 | a1 |= a2; |
| 338 | if (((nat->nat_dir == NAT_OUTBOUND) && |
| 339 | (a1 != ntohl(nat->nat_osrcaddr))) || |
| 340 | ((nat->nat_dir == NAT_INBOUND) && |
| 341 | (a1 != ntohl(nat->nat_nsrcaddr)))) { |
| 342 | DT3(ftp_PORT_error_address, nat_t *, nat, ftpside_t *, f, |
| 343 | u_int, a1); |
| 344 | if (softf->ipf_p_ftp_debug & DEBUG_ERROR) |
| 345 | printf("ipf_p_ftp_port:%s != nat->nat_inip\n" , "a1" ); |
| 346 | return APR_ERR(1); |
| 347 | } |
| 348 | |
| 349 | a5 = ipf_p_ftp_atoi(&s); |
| 350 | if (s == NULL) { |
| 351 | DT2(ftp_PORT_error_atoi_3, nat_t *, nat, ftpside_t *, f); |
| 352 | if (softf->ipf_p_ftp_debug & DEBUG_PARSE_ERR) |
| 353 | printf("ipf_p_ftp_port:ipf_p_ftp_atoi(%d) failed\n" , 3); |
| 354 | return 0; |
| 355 | } |
| 356 | if (*s == ')') |
| 357 | s++; |
| 358 | |
| 359 | /* |
| 360 | * check for CR-LF at the end. |
| 361 | */ |
| 362 | if (*s == '\n') |
| 363 | s--; |
| 364 | if ((*s != '\r') || (*(s + 1) != '\n')) { |
| 365 | DT2(ftp_PORT_error_no_crlf, nat_t *, nat, ftpside_t *, f); |
| 366 | if (softf->ipf_p_ftp_debug & DEBUG_PARSE_ERR) |
| 367 | printf("ipf_p_ftp_port:missing %s\n" , "cr-lf" ); |
| 368 | return 0; |
| 369 | } |
| 370 | s += 2; |
| 371 | a6 = a5 & 0xff; |
| 372 | |
| 373 | /* |
| 374 | * Calculate the source port. Verification of > 1024 is in |
| 375 | * ipf_p_ftp_addport. |
| 376 | */ |
| 377 | a5 >>= 8; |
| 378 | a5 &= 0xff; |
| 379 | sp = a5 << 8 | a6; |
| 380 | |
| 381 | /* |
| 382 | * Calculate new address parts for PORT command |
| 383 | */ |
| 384 | if (nat->nat_dir == NAT_INBOUND) |
| 385 | a1 = ntohl(nat->nat_ndstaddr); |
| 386 | else |
| 387 | a1 = ntohl(ip->ip_src.s_addr); |
| 388 | a1 = ntohl(ip->ip_src.s_addr); |
| 389 | a2 = (a1 >> 16) & 0xff; |
| 390 | a3 = (a1 >> 8) & 0xff; |
| 391 | a4 = a1 & 0xff; |
| 392 | a1 >>= 24; |
| 393 | olen = s - f->ftps_rptr; |
| 394 | snprintf(newbuf, sizeof(newbuf), "%s %u,%u,%u,%u,%u,%u\r\n" , |
| 395 | "PORT" , a1, a2, a3, a4, a5, a6); |
| 396 | |
| 397 | nlen = strlen(newbuf); |
| 398 | inc = nlen - olen; |
| 399 | if ((inc + fin->fin_plen) > 65535) { |
| 400 | DT3(ftp_PORT_error_inc, nat_t *, nat, ftpside_t *, f, |
| 401 | int, inc); |
| 402 | if (softf->ipf_p_ftp_debug & DEBUG_ERROR) |
| 403 | printf("ipf_p_ftp_port:inc(%d) + ip->ip_len > 65535\n" , |
| 404 | inc); |
| 405 | return 0; |
| 406 | } |
| 407 | |
| 408 | #if !defined(_KERNEL) |
| 409 | M_ADJ(m, inc); |
| 410 | #else |
| 411 | /* |
| 412 | * m_adj takes care of pkthdr.len, if required and treats inc<0 to |
| 413 | * mean remove -len bytes from the end of the packet. |
| 414 | * The mbuf chain will be extended if necessary by m_copyback(). |
| 415 | */ |
| 416 | if (inc < 0) |
| 417 | M_ADJ(m, inc); |
| 418 | #endif /* !defined(_KERNEL) */ |
| 419 | COPYBACK(m, off, nlen, newbuf); |
| 420 | fin->fin_flx |= FI_DOCKSUM; |
| 421 | |
| 422 | if (inc != 0) { |
| 423 | fin->fin_plen += inc; |
| 424 | ip->ip_len = htons(fin->fin_plen); |
| 425 | fin->fin_dlen += inc; |
| 426 | } |
| 427 | |
| 428 | f->ftps_cmd = FTPXY_C_PORT; |
| 429 | return ipf_p_ftp_addport(softf, fin, ip, nat, ftp, dlen, sp, inc); |
| 430 | } |
| 431 | |
| 432 | |
| 433 | int |
| 434 | ipf_p_ftp_addport(ipf_ftp_softc_t *softf, fr_info_t *fin, ip_t *ip, nat_t *nat, |
| 435 | ftpinfo_t *ftp, int dlen, int nport, int inc) |
| 436 | { |
| 437 | tcphdr_t tcph, *tcp2 = &tcph; |
| 438 | ipf_main_softc_t *softc; |
| 439 | ipf_nat_softc_t *softn; |
| 440 | int direction; |
| 441 | fr_info_t fi; |
| 442 | ipnat_t *ipn; |
| 443 | nat_t *nat2; |
| 444 | u_short sp; |
| 445 | int flags; |
| 446 | |
| 447 | softc = fin->fin_main_soft; |
| 448 | softn = softc->ipf_nat_soft; |
| 449 | |
| 450 | if ((ftp->ftp_pendnat != NULL) || (ftp->ftp_pendstate != NULL)) { |
| 451 | if (softf->ipf_p_ftp_single_xfer != 0) { |
| 452 | DT2(ftp_PORT_error_add_active, nat_t *, nat, |
| 453 | ftpinfo_t *, ftp); |
| 454 | if (softf->ipf_p_ftp_debug & DEBUG_ERROR) |
| 455 | printf("ipf_p_ftp_addport:xfer active %p/%p\n" , |
| 456 | ftp->ftp_pendnat, ftp->ftp_pendstate); |
| 457 | return 0; |
| 458 | } |
| 459 | ipf_p_ftp_setpending(softc, ftp); |
| 460 | } |
| 461 | |
| 462 | /* |
| 463 | * Add skeleton NAT entry for connection which will come back the |
| 464 | * other way. |
| 465 | */ |
| 466 | sp = nport; |
| 467 | /* |
| 468 | * Don't allow the PORT command to specify a port < 1024 due to |
| 469 | * security risks. |
| 470 | */ |
| 471 | if (sp < 1024) { |
| 472 | DT3(ftp_PORT_error_port, nat_t *, nat, ftpinfo_t *, ftp, |
| 473 | u_int, sp); |
| 474 | if (softf->ipf_p_ftp_debug & DEBUG_SECURITY) |
| 475 | printf("ipf_p_ftp_addport:sp(%d) < 1024\n" , sp); |
| 476 | return 0; |
| 477 | } |
| 478 | /* |
| 479 | * The server may not make the connection back from port 20, but |
| 480 | * it is the most likely so use it here to check for a conflicting |
| 481 | * mapping. |
| 482 | */ |
| 483 | bcopy((char *)fin, (char *)&fi, sizeof(fi)); |
| 484 | fi.fin_flx |= FI_IGNORE; |
| 485 | fi.fin_data[0] = sp; |
| 486 | fi.fin_data[1] = fin->fin_data[1] - 1; |
| 487 | fi.fin_src6 = nat->nat_ndst6; |
| 488 | fi.fin_dst6 = nat->nat_nsrc6; |
| 489 | |
| 490 | if (nat->nat_v[0] == 6) { |
| 491 | #ifndef USE_INET6 |
| 492 | return APR_INC(inc); |
| 493 | #endif |
| 494 | } |
| 495 | |
| 496 | /* |
| 497 | * Add skeleton NAT entry for connection which will come back the |
| 498 | * other way. |
| 499 | */ |
| 500 | #ifdef USE_INET6 |
| 501 | if (nat->nat_v[0] == 6) { |
| 502 | if (nat->nat_dir == NAT_OUTBOUND) { |
| 503 | nat2 = ipf_nat6_outlookup(&fi, IPN_TCP|NAT_SEARCH, |
| 504 | nat->nat_pr[1], |
| 505 | &nat->nat_osrc6.in6, |
| 506 | &nat->nat_odst6.in6); |
| 507 | } else { |
| 508 | nat2 = ipf_nat6_inlookup(&fi, IPN_TCP|NAT_SEARCH, |
| 509 | nat->nat_pr[0], |
| 510 | &nat->nat_odst6.in6, |
| 511 | &nat->nat_osrc6.in6); |
| 512 | } |
| 513 | } else |
| 514 | #endif |
| 515 | { |
| 516 | if (nat->nat_dir == NAT_OUTBOUND) { |
| 517 | nat2 = ipf_nat_outlookup(&fi, IPN_TCP|NAT_SEARCH, |
| 518 | nat->nat_pr[1], |
| 519 | nat->nat_osrcip, |
| 520 | nat->nat_odstip); |
| 521 | } else { |
| 522 | nat2 = ipf_nat_inlookup(&fi, IPN_TCP|NAT_SEARCH, |
| 523 | nat->nat_pr[0], |
| 524 | nat->nat_odstip, |
| 525 | nat->nat_osrcip); |
| 526 | } |
| 527 | } |
| 528 | if (nat2 != NULL) |
| 529 | return APR_INC(inc); |
| 530 | |
| 531 | ipn = ipf_proxy_rule_rev(nat); |
| 532 | if (ipn == NULL) |
| 533 | return APR_ERR(1); |
| 534 | ipn->in_use = 0; |
| 535 | |
| 536 | fi.fin_fr = &ftppxyfr; |
| 537 | fi.fin_dp = (char *)tcp2; |
| 538 | fi.fin_dlen = sizeof(*tcp2); |
| 539 | fi.fin_plen = fi.fin_hlen + sizeof(*tcp2); |
| 540 | fi.fin_flx &= FI_LOWTTL|FI_FRAG|FI_TCPUDP|FI_OPTIONS|FI_IGNORE; |
| 541 | fi.fin_data[1] = sp; |
| 542 | fi.fin_data[0] = 0; |
| 543 | |
| 544 | bzero((char *)tcp2, sizeof(*tcp2)); |
| 545 | tcp2->th_sport = 0; |
| 546 | tcp2->th_dport = htons(sp); |
| 547 | |
| 548 | tcp2->th_win = htons(8192); |
| 549 | TCP_OFF_A(tcp2, 5); |
| 550 | tcp2->th_flags = TH_SYN; |
| 551 | |
| 552 | if (nat->nat_dir == NAT_INBOUND) { |
| 553 | fi.fin_out = 1; |
| 554 | direction = NAT_OUTBOUND; |
| 555 | } else { |
| 556 | fi.fin_out = 0; |
| 557 | direction = NAT_INBOUND; |
| 558 | } |
| 559 | flags = SI_W_SPORT|NAT_SLAVE|IPN_TCP; |
| 560 | |
| 561 | MUTEX_ENTER(&softn->ipf_nat_new); |
| 562 | if (nat->nat_v[0] == 6) { |
| 563 | #ifdef USE_INET6 |
| 564 | nat2 = ipf_nat6_add(&fi, ipn, &ftp->ftp_pendnat, flags, |
| 565 | direction); |
| 566 | #endif |
| 567 | } else { |
| 568 | nat2 = ipf_nat_add(&fi, ipn, &ftp->ftp_pendnat, flags, |
| 569 | direction); |
| 570 | } |
| 571 | MUTEX_EXIT(&softn->ipf_nat_new); |
| 572 | |
| 573 | if (nat2 == NULL) { |
| 574 | KFREES(ipn, ipn->in_size); |
| 575 | return APR_ERR(1); |
| 576 | } |
| 577 | |
| 578 | (void) ipf_nat_proto(&fi, nat2, IPN_TCP); |
| 579 | MUTEX_ENTER(&nat2->nat_lock); |
| 580 | ipf_nat_update(&fi, nat2); |
| 581 | MUTEX_EXIT(&nat2->nat_lock); |
| 582 | fi.fin_ifp = NULL; |
| 583 | if (nat2->nat_dir == NAT_INBOUND) |
| 584 | fi.fin_dst6 = nat->nat_osrc6; |
| 585 | if (ipf_state_add(softc, &fi, (ipstate_t **)&ftp->ftp_pendstate, |
| 586 | SI_W_SPORT) != 0) |
| 587 | ipf_nat_setpending(softc, nat2); |
| 588 | |
| 589 | return APR_INC(inc); |
| 590 | } |
| 591 | |
| 592 | |
| 593 | int |
| 594 | ipf_p_ftp_client(ipf_ftp_softc_t *softf, fr_info_t *fin, ip_t *ip, nat_t *nat, |
| 595 | ftpinfo_t *ftp, int dlen) |
| 596 | { |
| 597 | char *rptr, *wptr, cmd[6], c; |
| 598 | ftpside_t *f; |
| 599 | int inc, i; |
| 600 | |
| 601 | inc = 0; |
| 602 | f = &ftp->ftp_side[0]; |
| 603 | rptr = f->ftps_rptr; |
| 604 | wptr = f->ftps_wptr; |
| 605 | |
| 606 | for (i = 0; (i < 5) && (i < dlen); i++) { |
| 607 | c = rptr[i]; |
| 608 | if (ISALPHA(c)) { |
| 609 | cmd[i] = TOUPPER(c); |
| 610 | } else { |
| 611 | cmd[i] = c; |
| 612 | } |
| 613 | } |
| 614 | cmd[i] = '\0'; |
| 615 | |
| 616 | ftp->ftp_incok = 0; |
| 617 | DT2(ftp_client_command, char [], cmd, int, ftp->ftp_passok); |
| 618 | if (!strncmp(cmd, "USER " , 5) || !strncmp(cmd, "XAUT " , 5)) { |
| 619 | if (ftp->ftp_passok == FTPXY_ADOK_1 || |
| 620 | ftp->ftp_passok == FTPXY_AUOK_1) { |
| 621 | ftp->ftp_passok = FTPXY_USER_2; |
| 622 | ftp->ftp_incok = 1; |
| 623 | } else { |
| 624 | ftp->ftp_passok = FTPXY_USER_1; |
| 625 | ftp->ftp_incok = 1; |
| 626 | } |
| 627 | } else if (!strncmp(cmd, "AUTH " , 5)) { |
| 628 | ftp->ftp_passok = FTPXY_AUTH_1; |
| 629 | ftp->ftp_incok = 1; |
| 630 | } else if (!strncmp(cmd, "PASS " , 5)) { |
| 631 | if (ftp->ftp_passok == FTPXY_USOK_1) { |
| 632 | ftp->ftp_passok = FTPXY_PASS_1; |
| 633 | ftp->ftp_incok = 1; |
| 634 | } else if (ftp->ftp_passok == FTPXY_USOK_2) { |
| 635 | ftp->ftp_passok = FTPXY_PASS_2; |
| 636 | ftp->ftp_incok = 1; |
| 637 | } |
| 638 | } else if ((ftp->ftp_passok == FTPXY_AUOK_1) && |
| 639 | !strncmp(cmd, "ADAT " , 5)) { |
| 640 | ftp->ftp_passok = FTPXY_ADAT_1; |
| 641 | ftp->ftp_incok = 1; |
| 642 | } else if ((ftp->ftp_passok == FTPXY_PAOK_1 || |
| 643 | ftp->ftp_passok == FTPXY_PAOK_2) && |
| 644 | !strncmp(cmd, "ACCT " , 5)) { |
| 645 | ftp->ftp_passok = FTPXY_ACCT_1; |
| 646 | ftp->ftp_incok = 1; |
| 647 | } else if ((ftp->ftp_passok == FTPXY_GO) && |
| 648 | !softf->ipf_p_ftp_pasvonly && |
| 649 | !strncmp(cmd, "PORT " , 5)) { |
| 650 | inc = ipf_p_ftp_port(softf, fin, ip, nat, ftp, dlen); |
| 651 | } else if ((ftp->ftp_passok == FTPXY_GO) && |
| 652 | !softf->ipf_p_ftp_pasvonly && |
| 653 | !strncmp(cmd, "EPRT " , 5)) { |
| 654 | inc = ipf_p_ftp_eprt(softf, fin, ip, nat, ftp, dlen); |
| 655 | } else if (softf->ipf_p_ftp_insecure && |
| 656 | !softf->ipf_p_ftp_pasvonly && |
| 657 | !strncmp(cmd, "PORT " , 5)) { |
| 658 | inc = ipf_p_ftp_port(softf, fin, ip, nat, ftp, dlen); |
| 659 | } |
| 660 | if (softf->ipf_p_ftp_debug & DEBUG_PARSE) |
| 661 | printf("ipf_p_ftp_client: cmd[%s] passok %d incok %d inc %d\n" , |
| 662 | cmd, ftp->ftp_passok, ftp->ftp_incok, inc); |
| 663 | |
| 664 | DT2(ftp_client_passok, char *, cmd, int, ftp->ftp_passok); |
| 665 | while ((*rptr++ != '\n') && (rptr < wptr)) |
| 666 | ; |
| 667 | f->ftps_rptr = rptr; |
| 668 | return inc; |
| 669 | } |
| 670 | |
| 671 | |
| 672 | int |
| 673 | ipf_p_ftp_pasv(ipf_ftp_softc_t *softf, fr_info_t *fin, ip_t *ip, nat_t *nat, |
| 674 | ftpinfo_t *ftp, int dlen) |
| 675 | { |
| 676 | u_int a1, a2, a3, a4, data_ip; |
| 677 | char newbuf[IPF_FTPBUFSZ]; |
| 678 | const char *brackets[2]; |
| 679 | u_short a5, a6; |
| 680 | ftpside_t *f; |
| 681 | char *s; |
| 682 | |
| 683 | if ((softf->ipf_p_ftp_forcepasv != 0) && |
| 684 | (ftp->ftp_side[0].ftps_cmd != FTPXY_C_PASV)) { |
| 685 | DT2(ftp_PASV_error_state, nat_t *, nat, ftpinfo_t *, ftp); |
| 686 | if (softf->ipf_p_ftp_debug & DEBUG_ERROR) |
| 687 | printf("ipf_p_ftp_pasv:ftps_cmd(%d) != FTPXY_C_PASV\n" , |
| 688 | ftp->ftp_side[0].ftps_cmd); |
| 689 | return 0; |
| 690 | } |
| 691 | |
| 692 | f = &ftp->ftp_side[1]; |
| 693 | |
| 694 | #define PASV_REPLEN 24 |
| 695 | /* |
| 696 | * Check for PASV reply message. |
| 697 | */ |
| 698 | if (dlen < IPF_MIN227LEN) { |
| 699 | DT3(ftp_PASV_error_short, nat_t *, nat, ftpinfo_t *, ftp, |
| 700 | int, dlen); |
| 701 | if (softf->ipf_p_ftp_debug & DEBUG_ERROR) |
| 702 | printf("ipf_p_ftp_pasv:dlen(%d) < IPF_MIN227LEN\n" , |
| 703 | dlen); |
| 704 | return 0; |
| 705 | } else if (strncmp(f->ftps_rptr, |
| 706 | "227 Entering Passive Mod" , PASV_REPLEN)) { |
| 707 | DT2(ftp_PASV_error_string, nat_t *, nat, ftpinfo_t *, ftp); |
| 708 | if (softf->ipf_p_ftp_debug & DEBUG_PARSE_ERR) |
| 709 | printf("ipf_p_ftp_pasv:%d reply wrong\n" , 227); |
| 710 | return 0; |
| 711 | } |
| 712 | |
| 713 | brackets[0] = "" ; |
| 714 | brackets[1] = "" ; |
| 715 | /* |
| 716 | * Skip the PASV reply + space |
| 717 | */ |
| 718 | s = f->ftps_rptr + PASV_REPLEN; |
| 719 | while (*s && !ISDIGIT(*s)) { |
| 720 | if (*s == '(') { |
| 721 | brackets[0] = "(" ; |
| 722 | brackets[1] = ")" ; |
| 723 | } |
| 724 | s++; |
| 725 | } |
| 726 | |
| 727 | /* |
| 728 | * Pick out the address components, two at a time. |
| 729 | */ |
| 730 | a1 = ipf_p_ftp_atoi(&s); |
| 731 | if (s == NULL) { |
| 732 | DT2(ftp_PASV_error_atoi_1, nat_t *, nat, ftpside_t *, f); |
| 733 | if (softf->ipf_p_ftp_debug & DEBUG_PARSE_ERR) |
| 734 | printf("ipf_p_ftp_pasv:ipf_p_ftp_atoi(%d) failed\n" , 1); |
| 735 | return 0; |
| 736 | } |
| 737 | a2 = ipf_p_ftp_atoi(&s); |
| 738 | if (s == NULL) { |
| 739 | DT2(ftp_PASV_error_atoi_2, nat_t *, nat, ftpside_t *, f); |
| 740 | if (softf->ipf_p_ftp_debug & DEBUG_PARSE_ERR) |
| 741 | printf("ipf_p_ftp_pasv:ipf_p_ftp_atoi(%d) failed\n" , 2); |
| 742 | return 0; |
| 743 | } |
| 744 | |
| 745 | /* |
| 746 | * check that IP address in the PASV reply is the same as the |
| 747 | * sender of the command - prevents using PASV for port scanning. |
| 748 | */ |
| 749 | a1 <<= 16; |
| 750 | a1 |= a2; |
| 751 | |
| 752 | if (((nat->nat_dir == NAT_INBOUND) && |
| 753 | (a1 != ntohl(nat->nat_ndstaddr))) || |
| 754 | ((nat->nat_dir == NAT_OUTBOUND) && |
| 755 | (a1 != ntohl(nat->nat_odstaddr)))) { |
| 756 | DT3(ftp_PASV_error_address, nat_t *, nat, ftpside_t *, f, |
| 757 | u_int, a1); |
| 758 | if (softf->ipf_p_ftp_debug & DEBUG_ERROR) |
| 759 | printf("ipf_p_ftp_pasv:%s != nat->nat_oip\n" , "a1" ); |
| 760 | return 0; |
| 761 | } |
| 762 | |
| 763 | a5 = ipf_p_ftp_atoi(&s); |
| 764 | if (s == NULL) { |
| 765 | DT2(ftp_PASV_error_atoi_3, nat_t *, nat, ftpside_t *, f); |
| 766 | if (softf->ipf_p_ftp_debug & DEBUG_PARSE_ERR) |
| 767 | printf("ipf_p_ftp_pasv:ipf_p_ftp_atoi(%d) failed\n" , 3); |
| 768 | return 0; |
| 769 | } |
| 770 | |
| 771 | if (*s == ')') |
| 772 | s++; |
| 773 | if (*s == '.') |
| 774 | s++; |
| 775 | if (*s == '\n') |
| 776 | s--; |
| 777 | /* |
| 778 | * check for CR-LF at the end. |
| 779 | */ |
| 780 | if ((*s != '\r') || (*(s + 1) != '\n')) { |
| 781 | DT(pasv_missing_crlf); |
| 782 | if (softf->ipf_p_ftp_debug & DEBUG_PARSE_ERR) |
| 783 | printf("ipf_p_ftp_pasv:missing %s" , "cr-lf\n" ); |
| 784 | return 0; |
| 785 | } |
| 786 | s += 2; |
| 787 | |
| 788 | a6 = a5 & 0xff; |
| 789 | a5 >>= 8; |
| 790 | /* |
| 791 | * Calculate new address parts for 227 reply |
| 792 | */ |
| 793 | if (nat->nat_dir == NAT_INBOUND) { |
| 794 | data_ip = nat->nat_odstaddr; |
| 795 | a1 = ntohl(data_ip); |
| 796 | } else |
| 797 | data_ip = htonl(a1); |
| 798 | |
| 799 | a2 = (a1 >> 16) & 0xff; |
| 800 | a3 = (a1 >> 8) & 0xff; |
| 801 | a4 = a1 & 0xff; |
| 802 | a1 >>= 24; |
| 803 | |
| 804 | snprintf(newbuf, sizeof(newbuf), "%s %s%u,%u,%u,%u,%u,%u%s\r\n" , |
| 805 | "227 Entering Passive Mode" , brackets[0], a1, a2, a3, a4, |
| 806 | a5, a6, brackets[1]); |
| 807 | return ipf_p_ftp_pasvreply(softf, fin, ip, nat, ftp, (a5 << 8 | a6), |
| 808 | newbuf, s); |
| 809 | } |
| 810 | |
| 811 | int |
| 812 | ipf_p_ftp_pasvreply(ipf_ftp_softc_t *softf, fr_info_t *fin, ip_t *ip, |
| 813 | nat_t *nat, ftpinfo_t *ftp, u_int port, char *newmsg, char *s) |
| 814 | { |
| 815 | int inc, off, nflags; |
| 816 | tcphdr_t *tcp, tcph, *tcp2; |
| 817 | ipf_main_softc_t *softc; |
| 818 | ipf_nat_softc_t *softn; |
| 819 | size_t nlen, olen; |
| 820 | #ifdef USE_INET6 |
| 821 | ip6_t *ip6; |
| 822 | #endif |
| 823 | ipnat_t *ipn; |
| 824 | fr_info_t fi; |
| 825 | ftpside_t *f; |
| 826 | nat_t *nat2 = NULL; |
| 827 | mb_t *m; |
| 828 | |
| 829 | softc = fin->fin_main_soft; |
| 830 | softn = softc->ipf_nat_soft; |
| 831 | |
| 832 | if ((ftp->ftp_pendnat != NULL) || (ftp->ftp_pendstate != NULL)) |
| 833 | ipf_p_ftp_setpending(softc, ftp); |
| 834 | |
| 835 | m = fin->fin_m; |
| 836 | tcp = (tcphdr_t *)fin->fin_dp; |
| 837 | off = (char *)tcp - (char *)ip + (TCP_OFF(tcp) << 2) + fin->fin_ipoff; |
| 838 | |
| 839 | tcp2 = &tcph; |
| 840 | inc = 0; |
| 841 | |
| 842 | f = &ftp->ftp_side[1]; |
| 843 | olen = s - f->ftps_rptr; |
| 844 | nlen = strlen(newmsg); |
| 845 | inc = nlen - olen; |
| 846 | if ((inc + fin->fin_plen) > 65535) { |
| 847 | DT3(ftp_PASV_error_inc, nat_t *, nat, ftpside_t *, f, |
| 848 | int, inc); |
| 849 | if (softf->ipf_p_ftp_debug & DEBUG_ERROR) |
| 850 | printf("ipf_p_ftp_pasv:inc(%d) + ip->ip_len > 65535\n" , |
| 851 | inc); |
| 852 | return 0; |
| 853 | } |
| 854 | |
| 855 | ipn = ipf_proxy_rule_fwd(nat); |
| 856 | if (ipn == NULL) |
| 857 | return APR_ERR(1); |
| 858 | ipn->in_use = 0; |
| 859 | |
| 860 | /* |
| 861 | * Add skeleton NAT entry for connection which will come back the |
| 862 | * other way. |
| 863 | */ |
| 864 | bzero((char *)tcp2, sizeof(*tcp2)); |
| 865 | bcopy((char *)fin, (char *)&fi, sizeof(fi)); |
| 866 | fi.fin_flx |= FI_IGNORE; |
| 867 | fi.fin_data[0] = 0; |
| 868 | fi.fin_data[1] = port; |
| 869 | nflags = IPN_TCP|SI_W_SPORT; |
| 870 | |
| 871 | fi.fin_fr = &ftppxyfr; |
| 872 | fi.fin_dp = (char *)tcp2; |
| 873 | fi.fin_out = 1 - fin->fin_out; |
| 874 | fi.fin_dlen = sizeof(*tcp2); |
| 875 | fi.fin_src6 = nat->nat_osrc6; |
| 876 | fi.fin_dst6 = nat->nat_odst6; |
| 877 | fi.fin_plen = fi.fin_hlen + sizeof(*tcp); |
| 878 | fi.fin_flx &= FI_LOWTTL|FI_FRAG|FI_TCPUDP|FI_OPTIONS|FI_IGNORE; |
| 879 | |
| 880 | TCP_OFF_A(tcp2, 5); |
| 881 | tcp2->th_flags = TH_SYN; |
| 882 | tcp2->th_win = htons(8192); |
| 883 | tcp2->th_dport = htons(port); |
| 884 | |
| 885 | MUTEX_ENTER(&softn->ipf_nat_new); |
| 886 | if (nat->nat_v[0] == 6) { |
| 887 | #ifdef USE_INET6 |
| 888 | nat2 = ipf_nat6_add(&fi, ipn, &ftp->ftp_pendnat, |
| 889 | nflags, nat->nat_dir); |
| 890 | #endif |
| 891 | } else { |
| 892 | nat2 = ipf_nat_add(&fi, ipn, &ftp->ftp_pendnat, |
| 893 | nflags, nat->nat_dir); |
| 894 | } |
| 895 | MUTEX_EXIT(&softn->ipf_nat_new); |
| 896 | |
| 897 | if (nat2 == NULL) { |
| 898 | KFREES(ipn, ipn->in_size); |
| 899 | return APR_ERR(1); |
| 900 | } |
| 901 | |
| 902 | (void) ipf_nat_proto(&fi, nat2, IPN_TCP); |
| 903 | MUTEX_ENTER(&nat2->nat_lock); |
| 904 | ipf_nat_update(&fi, nat2); |
| 905 | MUTEX_EXIT(&nat2->nat_lock); |
| 906 | fi.fin_ifp = NULL; |
| 907 | if (nat->nat_dir == NAT_INBOUND) { |
| 908 | if (nat->nat_v[0] == 6) { |
| 909 | #ifdef USE_INET6 |
| 910 | fi.fin_dst6 = nat->nat_ndst6; |
| 911 | #endif |
| 912 | } else { |
| 913 | fi.fin_daddr = nat->nat_ndstaddr; |
| 914 | } |
| 915 | } |
| 916 | if (ipf_state_add(softc, &fi, (ipstate_t **)&ftp->ftp_pendstate, |
| 917 | SI_W_SPORT) != 0) |
| 918 | ipf_nat_setpending(softc, nat2); |
| 919 | |
| 920 | #if !defined(_KERNEL) |
| 921 | M_ADJ(m, inc); |
| 922 | #else |
| 923 | /* |
| 924 | * m_adj takes care of pkthdr.len, if required and treats inc<0 to |
| 925 | * mean remove -len bytes from the end of the packet. |
| 926 | * The mbuf chain will be extended if necessary by m_copyback(). |
| 927 | */ |
| 928 | if (inc < 0) |
| 929 | M_ADJ(m, inc); |
| 930 | #endif /* !defined(_KERNEL) */ |
| 931 | COPYBACK(m, off, nlen, newmsg); |
| 932 | fin->fin_flx |= FI_DOCKSUM; |
| 933 | |
| 934 | if (inc != 0) { |
| 935 | fin->fin_plen += inc; |
| 936 | fin->fin_dlen += inc; |
| 937 | if (nat->nat_v[0] == 6) { |
| 938 | #ifdef USE_INET6 |
| 939 | ip6 = (ip6_t *)fin->fin_ip; |
| 940 | u_short len = ntohs(ip6->ip6_plen) + inc; |
| 941 | ip6->ip6_plen = htons(len); |
| 942 | #endif |
| 943 | } else { |
| 944 | ip->ip_len = htons(fin->fin_plen); |
| 945 | } |
| 946 | } |
| 947 | |
| 948 | return APR_INC(inc); |
| 949 | } |
| 950 | |
| 951 | |
| 952 | int |
| 953 | ipf_p_ftp_server(ipf_ftp_softc_t *softf, fr_info_t *fin, ip_t *ip, nat_t *nat, |
| 954 | ftpinfo_t *ftp, int dlen) |
| 955 | { |
| 956 | char *rptr, *wptr; |
| 957 | ftpside_t *f; |
| 958 | int inc; |
| 959 | |
| 960 | inc = 0; |
| 961 | f = &ftp->ftp_side[1]; |
| 962 | rptr = f->ftps_rptr; |
| 963 | wptr = f->ftps_wptr; |
| 964 | |
| 965 | DT2(ftp_server_response, char *, rptr, int, ftp->ftp_passok); |
| 966 | if (*rptr == ' ') |
| 967 | goto server_cmd_ok; |
| 968 | if (!ISDIGIT(*rptr) || !ISDIGIT(*(rptr + 1)) || !ISDIGIT(*(rptr + 2))) |
| 969 | return 0; |
| 970 | if (softf->ipf_p_ftp_debug & DEBUG_PARSE) |
| 971 | printf("ipf_p_ftp_server_1: cmd[%4.4s] passok %d\n" , |
| 972 | rptr, ftp->ftp_passok); |
| 973 | if (ftp->ftp_passok == FTPXY_GO) { |
| 974 | if (!strncmp(rptr, "227 " , 4)) |
| 975 | inc = ipf_p_ftp_pasv(softf, fin, ip, nat, ftp, dlen); |
| 976 | else if (!strncmp(rptr, "229 " , 4)) |
| 977 | inc = ipf_p_ftp_epsv(softf, fin, ip, nat, ftp, dlen); |
| 978 | else if (strncmp(rptr, "200" , 3)) { |
| 979 | /* |
| 980 | * 200 is returned for a successful command. |
| 981 | */ |
| 982 | ; |
| 983 | } |
| 984 | } else if (softf->ipf_p_ftp_insecure && !strncmp(rptr, "227 " , 4)) { |
| 985 | inc = ipf_p_ftp_pasv(softf, fin, ip, nat, ftp, dlen); |
| 986 | } else if (softf->ipf_p_ftp_insecure && !strncmp(rptr, "229 " , 4)) { |
| 987 | inc = ipf_p_ftp_epsv(softf, fin, ip, nat, ftp, dlen); |
| 988 | } else if (*rptr == '5' || *rptr == '4') |
| 989 | ftp->ftp_passok = FTPXY_INIT; |
| 990 | else if (ftp->ftp_incok) { |
| 991 | if (*rptr == '3') { |
| 992 | if (ftp->ftp_passok == FTPXY_ACCT_1) |
| 993 | ftp->ftp_passok = FTPXY_GO; |
| 994 | else |
| 995 | ftp->ftp_passok++; |
| 996 | } else if (*rptr == '2') { |
| 997 | switch (ftp->ftp_passok) |
| 998 | { |
| 999 | case FTPXY_USER_1 : |
| 1000 | case FTPXY_USER_2 : |
| 1001 | case FTPXY_PASS_1 : |
| 1002 | case FTPXY_PASS_2 : |
| 1003 | case FTPXY_ACCT_1 : |
| 1004 | ftp->ftp_passok = FTPXY_GO; |
| 1005 | break; |
| 1006 | default : |
| 1007 | ftp->ftp_passok += 3; |
| 1008 | break; |
| 1009 | } |
| 1010 | } |
| 1011 | } |
| 1012 | ftp->ftp_incok = 0; |
| 1013 | server_cmd_ok: |
| 1014 | if (softf->ipf_p_ftp_debug & DEBUG_PARSE) |
| 1015 | printf("ipf_p_ftp_server_2: cmd[%4.4s] passok %d\n" , |
| 1016 | rptr, ftp->ftp_passok); |
| 1017 | DT3(ftp_server_passok, char *,rptr, int, ftp->ftp_incok, |
| 1018 | int, ftp->ftp_passok); |
| 1019 | |
| 1020 | while ((*rptr++ != '\n') && (rptr < wptr)) |
| 1021 | ; |
| 1022 | f->ftps_rptr = rptr; |
| 1023 | return inc; |
| 1024 | } |
| 1025 | |
| 1026 | |
| 1027 | /* |
| 1028 | * 0 FTPXY_JUNK_OK |
| 1029 | * 1 FTPXY_JUNK_BAD |
| 1030 | * 2 FTPXY_JUNK_EOL |
| 1031 | * 3 FTPXY_JUNK_CONT |
| 1032 | * |
| 1033 | * Look to see if the buffer starts with something which we recognise as |
| 1034 | * being the correct syntax for the FTP protocol. |
| 1035 | */ |
| 1036 | int |
| 1037 | ipf_p_ftp_client_valid(ipf_ftp_softc_t *softf, ftpside_t *ftps, char *buf, |
| 1038 | size_t len) |
| 1039 | { |
| 1040 | register char *s, c, pc; |
| 1041 | register size_t i = len; |
| 1042 | char cmd[5]; |
| 1043 | |
| 1044 | s = buf; |
| 1045 | |
| 1046 | if (ftps->ftps_junk == FTPXY_JUNK_BAD) |
| 1047 | return FTPXY_JUNK_BAD; |
| 1048 | |
| 1049 | if (i < 5) { |
| 1050 | DT1(client_valid, int, i); |
| 1051 | if (softf->ipf_p_ftp_debug & DEBUG_ERROR) |
| 1052 | printf("ipf_p_ftp_client_valid:i(%d) < 5\n" , (int)i); |
| 1053 | return 2; |
| 1054 | } |
| 1055 | |
| 1056 | i--; |
| 1057 | c = *s++; |
| 1058 | |
| 1059 | if (ISALPHA(c)) { |
| 1060 | cmd[0] = TOUPPER(c); |
| 1061 | c = *s++; |
| 1062 | i--; |
| 1063 | if (ISALPHA(c)) { |
| 1064 | cmd[1] = TOUPPER(c); |
| 1065 | c = *s++; |
| 1066 | i--; |
| 1067 | if (ISALPHA(c)) { |
| 1068 | cmd[2] = TOUPPER(c); |
| 1069 | c = *s++; |
| 1070 | i--; |
| 1071 | if (ISALPHA(c)) { |
| 1072 | cmd[3] = TOUPPER(c); |
| 1073 | c = *s++; |
| 1074 | i--; |
| 1075 | if ((c != ' ') && (c != '\r')) |
| 1076 | goto bad_client_command; |
| 1077 | } else if ((c != ' ') && (c != '\r')) |
| 1078 | goto bad_client_command; |
| 1079 | } else |
| 1080 | goto bad_client_command; |
| 1081 | } else |
| 1082 | goto bad_client_command; |
| 1083 | } else { |
| 1084 | bad_client_command: |
| 1085 | DT4(client_junk, int, len, int, i, int, c, char *, buf); |
| 1086 | if (softf->ipf_p_ftp_debug & DEBUG_PARSE_ERR) |
| 1087 | printf("%s:bad:junk %d len %d/%d c 0x%x buf [%*.*s]\n" , |
| 1088 | "ipf_p_ftp_client_valid" , |
| 1089 | ftps->ftps_junk, (int)len, (int)i, c, |
| 1090 | (int)len, (int)len, buf); |
| 1091 | return FTPXY_JUNK_BAD; |
| 1092 | } |
| 1093 | |
| 1094 | for (; i; i--) { |
| 1095 | pc = c; |
| 1096 | c = *s++; |
| 1097 | if ((pc == '\r') && (c == '\n')) { |
| 1098 | cmd[4] = '\0'; |
| 1099 | if (!strcmp(cmd, "PASV" )) { |
| 1100 | ftps->ftps_cmd = FTPXY_C_PASV; |
| 1101 | } else if (!strcmp(cmd, "EPSV" )) { |
| 1102 | ftps->ftps_cmd = FTPXY_C_EPSV; |
| 1103 | } else { |
| 1104 | ftps->ftps_cmd = 0; |
| 1105 | } |
| 1106 | return 0; |
| 1107 | } |
| 1108 | } |
| 1109 | #if !defined(_KERNEL) |
| 1110 | printf("ipf_p_ftp_client_valid:junk after cmd[%*.*s]\n" , |
| 1111 | (int)len, (int)len, buf); |
| 1112 | #endif |
| 1113 | return FTPXY_JUNK_EOL; |
| 1114 | } |
| 1115 | |
| 1116 | |
| 1117 | int |
| 1118 | ipf_p_ftp_server_valid(ipf_ftp_softc_t *softf, ftpside_t *ftps, char *buf, |
| 1119 | size_t len) |
| 1120 | { |
| 1121 | register char *s, c, pc; |
| 1122 | register size_t i = len; |
| 1123 | int cmd; |
| 1124 | |
| 1125 | s = buf; |
| 1126 | cmd = 0; |
| 1127 | |
| 1128 | if (ftps->ftps_junk == FTPXY_JUNK_BAD) |
| 1129 | return FTPXY_JUNK_BAD; |
| 1130 | |
| 1131 | if (i < 5) { |
| 1132 | DT1(server_valid, int, i); |
| 1133 | if (softf->ipf_p_ftp_debug & DEBUG_PARSE_ERR) |
| 1134 | printf("ipf_p_ftp_servert_valid:i(%d) < 5\n" , (int)i); |
| 1135 | return 2; |
| 1136 | } |
| 1137 | |
| 1138 | c = *s++; |
| 1139 | i--; |
| 1140 | if (c == ' ') { |
| 1141 | cmd = -1; |
| 1142 | goto search_eol; |
| 1143 | } |
| 1144 | |
| 1145 | if (ISDIGIT(c)) { |
| 1146 | cmd = (c - '0') * 100; |
| 1147 | c = *s++; |
| 1148 | i--; |
| 1149 | if (ISDIGIT(c)) { |
| 1150 | cmd += (c - '0') * 10; |
| 1151 | c = *s++; |
| 1152 | i--; |
| 1153 | if (ISDIGIT(c)) { |
| 1154 | cmd += (c - '0'); |
| 1155 | c = *s++; |
| 1156 | i--; |
| 1157 | if ((c != '-') && (c != ' ')) |
| 1158 | goto bad_server_command; |
| 1159 | if (c == '-') |
| 1160 | return FTPXY_JUNK_CONT; |
| 1161 | } else |
| 1162 | goto bad_server_command; |
| 1163 | } else |
| 1164 | goto bad_server_command; |
| 1165 | } else { |
| 1166 | bad_server_command: |
| 1167 | DT4(server_junk, int len, buf, int, i, int, c, char *, buf); |
| 1168 | if (softf->ipf_p_ftp_debug & DEBUG_PARSE_INFO) |
| 1169 | printf("%s:bad:junk %d len %d/%d c 0x%x buf [%*.*s]\n" , |
| 1170 | "ipf_p_ftp_server_valid" , |
| 1171 | ftps->ftps_junk, (int)len, (int)i, |
| 1172 | c, (int)len, (int)len, buf); |
| 1173 | if (ftps->ftps_junk == FTPXY_JUNK_CONT) |
| 1174 | return FTPXY_JUNK_CONT; |
| 1175 | return FTPXY_JUNK_BAD; |
| 1176 | } |
| 1177 | search_eol: |
| 1178 | for (; i; i--) { |
| 1179 | pc = c; |
| 1180 | c = *s++; |
| 1181 | if ((pc == '\r') && (c == '\n')) { |
| 1182 | if (cmd == -1) { |
| 1183 | if (ftps->ftps_junk == FTPXY_JUNK_CONT) |
| 1184 | return FTPXY_JUNK_CONT; |
| 1185 | } else { |
| 1186 | ftps->ftps_cmd = cmd; |
| 1187 | } |
| 1188 | return FTPXY_JUNK_OK; |
| 1189 | } |
| 1190 | } |
| 1191 | |
| 1192 | DT2(junk_eol, int, len, char *, buf); |
| 1193 | if (softf->ipf_p_ftp_debug & DEBUG_PARSE_INFO) |
| 1194 | printf("ipf_p_ftp_server_valid:junk after cmd[%*.*s]\n" , |
| 1195 | (int)len, (int)len, buf); |
| 1196 | return FTPXY_JUNK_EOL; |
| 1197 | } |
| 1198 | |
| 1199 | |
| 1200 | int |
| 1201 | ipf_p_ftp_valid(ipf_ftp_softc_t *softf, ftpinfo_t *ftp, int side, char *buf, |
| 1202 | size_t len) |
| 1203 | { |
| 1204 | ftpside_t *ftps; |
| 1205 | int ret; |
| 1206 | |
| 1207 | ftps = &ftp->ftp_side[side]; |
| 1208 | |
| 1209 | if (side == 0) |
| 1210 | ret = ipf_p_ftp_client_valid(softf, ftps, buf, len); |
| 1211 | else |
| 1212 | ret = ipf_p_ftp_server_valid(softf, ftps, buf, len); |
| 1213 | return ret; |
| 1214 | } |
| 1215 | |
| 1216 | |
| 1217 | /* |
| 1218 | * For map rules, the following applies: |
| 1219 | * rv == 0 for outbound processing, |
| 1220 | * rv == 1 for inbound processing. |
| 1221 | * For rdr rules, the following applies: |
| 1222 | * rv == 0 for inbound processing, |
| 1223 | * rv == 1 for outbound processing. |
| 1224 | */ |
| 1225 | int |
| 1226 | ipf_p_ftp_process(ipf_ftp_softc_t *softf, fr_info_t *fin, nat_t *nat, |
| 1227 | ftpinfo_t *ftp, int rv) |
| 1228 | { |
| 1229 | int mlen, len, off, inc, i, sel, sel2, ok, ackoff, seqoff, retry; |
| 1230 | char *rptr, *wptr, *s; |
| 1231 | u_32_t thseq, thack; |
| 1232 | ap_session_t *aps; |
| 1233 | ftpside_t *f, *t; |
| 1234 | tcphdr_t *tcp; |
| 1235 | ip_t *ip; |
| 1236 | mb_t *m; |
| 1237 | |
| 1238 | m = fin->fin_m; |
| 1239 | ip = fin->fin_ip; |
| 1240 | tcp = (tcphdr_t *)fin->fin_dp; |
| 1241 | off = (char *)tcp - (char *)ip + (TCP_OFF(tcp) << 2) + fin->fin_ipoff; |
| 1242 | |
| 1243 | f = &ftp->ftp_side[rv]; |
| 1244 | t = &ftp->ftp_side[1 - rv]; |
| 1245 | thseq = ntohl(tcp->th_seq); |
| 1246 | thack = ntohl(tcp->th_ack); |
| 1247 | #ifdef __sgi |
| 1248 | mlen = fin->fin_plen - off; |
| 1249 | #else |
| 1250 | mlen = MSGDSIZE(m) - off; |
| 1251 | #endif |
| 1252 | |
| 1253 | DT3(process_debug, tcphdr_t *, tcp, int, off, int, mlen); |
| 1254 | if (softf->ipf_p_ftp_debug & DEBUG_INFO) |
| 1255 | printf("ipf_p_ftp_process: %d:%d,%d, mlen %d flags %x\n" , |
| 1256 | fin->fin_out, fin->fin_sport, fin->fin_dport, |
| 1257 | mlen, tcp->th_flags); |
| 1258 | |
| 1259 | if ((mlen == 0) && ((tcp->th_flags & TH_OPENING) == TH_OPENING)) { |
| 1260 | f->ftps_seq[0] = thseq + 1; |
| 1261 | t->ftps_seq[0] = thack; |
| 1262 | return 0; |
| 1263 | } else if (mlen < 0) { |
| 1264 | return 0; |
| 1265 | } |
| 1266 | |
| 1267 | aps = nat->nat_aps; |
| 1268 | |
| 1269 | sel = aps->aps_sel[1 - rv]; |
| 1270 | sel2 = aps->aps_sel[rv]; |
| 1271 | if (rv == 1) { |
| 1272 | seqoff = aps->aps_seqoff[sel]; |
| 1273 | if (aps->aps_seqmin[sel] > seqoff + thseq) |
| 1274 | seqoff = aps->aps_seqoff[!sel]; |
| 1275 | ackoff = aps->aps_ackoff[sel2]; |
| 1276 | if (aps->aps_ackmin[sel2] > ackoff + thack) |
| 1277 | ackoff = aps->aps_ackoff[!sel2]; |
| 1278 | } else { |
| 1279 | seqoff = aps->aps_ackoff[sel]; |
| 1280 | if (softf->ipf_p_ftp_debug & DEBUG_INFO) |
| 1281 | printf("seqoff %d thseq %x ackmin %x\n" , seqoff, thseq, |
| 1282 | aps->aps_ackmin[sel]); |
| 1283 | if (aps->aps_ackmin[sel] > seqoff + thseq) |
| 1284 | seqoff = aps->aps_ackoff[!sel]; |
| 1285 | |
| 1286 | ackoff = aps->aps_seqoff[sel2]; |
| 1287 | if (softf->ipf_p_ftp_debug & DEBUG_INFO) |
| 1288 | printf("ackoff %d thack %x seqmin %x\n" , ackoff, thack, |
| 1289 | aps->aps_seqmin[sel2]); |
| 1290 | if (ackoff > 0) { |
| 1291 | if (aps->aps_seqmin[sel2] > ackoff + thack) |
| 1292 | ackoff = aps->aps_seqoff[!sel2]; |
| 1293 | } else { |
| 1294 | if (aps->aps_seqmin[sel2] > thack) |
| 1295 | ackoff = aps->aps_seqoff[!sel2]; |
| 1296 | } |
| 1297 | } |
| 1298 | if (softf->ipf_p_ftp_debug & DEBUG_INFO) { |
| 1299 | printf("%s: %x seq %x/%d ack %x/%d len %d/%d off %d\n" , |
| 1300 | rv ? "IN" : "OUT" , tcp->th_flags, thseq, seqoff, |
| 1301 | thack, ackoff, mlen, fin->fin_plen, off); |
| 1302 | printf("sel %d seqmin %x/%x offset %d/%d\n" , sel, |
| 1303 | aps->aps_seqmin[sel], aps->aps_seqmin[sel2], |
| 1304 | aps->aps_seqoff[sel], aps->aps_seqoff[sel2]); |
| 1305 | printf("sel %d ackmin %x/%x offset %d/%d\n" , sel2, |
| 1306 | aps->aps_ackmin[sel], aps->aps_ackmin[sel2], |
| 1307 | aps->aps_ackoff[sel], aps->aps_ackoff[sel2]); |
| 1308 | } |
| 1309 | |
| 1310 | /* |
| 1311 | * XXX - Ideally, this packet should get dropped because we now know |
| 1312 | * that it is out of order (and there is no real danger in doing so |
| 1313 | * apart from causing packets to go through here ordered). |
| 1314 | */ |
| 1315 | if (softf->ipf_p_ftp_debug & DEBUG_INFO) { |
| 1316 | printf("rv %d t:seq[0] %x seq[1] %x %d/%d\n" , |
| 1317 | rv, t->ftps_seq[0], t->ftps_seq[1], seqoff, ackoff); |
| 1318 | } |
| 1319 | |
| 1320 | ok = 0; |
| 1321 | if (t->ftps_seq[0] == 0) { |
| 1322 | t->ftps_seq[0] = thack; |
| 1323 | ok = 1; |
| 1324 | } else { |
| 1325 | if (ackoff == 0) { |
| 1326 | if (t->ftps_seq[0] == thack) |
| 1327 | ok = 1; |
| 1328 | else if (t->ftps_seq[1] == thack) { |
| 1329 | t->ftps_seq[0] = thack; |
| 1330 | ok = 1; |
| 1331 | } |
| 1332 | } else { |
| 1333 | if (t->ftps_seq[0] + ackoff == thack) { |
| 1334 | t->ftps_seq[0] = thack; |
| 1335 | ok = 1; |
| 1336 | } else if (t->ftps_seq[0] == thack + ackoff) { |
| 1337 | t->ftps_seq[0] = thack + ackoff; |
| 1338 | ok = 1; |
| 1339 | } else if (t->ftps_seq[1] + ackoff == thack) { |
| 1340 | t->ftps_seq[0] = thack; |
| 1341 | ok = 1; |
| 1342 | } else if (t->ftps_seq[1] == thack + ackoff) { |
| 1343 | t->ftps_seq[0] = thack + ackoff; |
| 1344 | ok = 1; |
| 1345 | } |
| 1346 | } |
| 1347 | } |
| 1348 | |
| 1349 | if (softf->ipf_p_ftp_debug & DEBUG_INFO) { |
| 1350 | if (!ok) |
| 1351 | printf("%s ok\n" , "not" ); |
| 1352 | } |
| 1353 | |
| 1354 | if (!mlen) { |
| 1355 | if (t->ftps_seq[0] + ackoff != thack && |
| 1356 | t->ftps_seq[1] + ackoff != thack) { |
| 1357 | DT3(thack, ftpside_t *t, t, int, ackoff, u_32_t, thack); |
| 1358 | if (softf->ipf_p_ftp_debug & DEBUG_ERROR) { |
| 1359 | printf("%s:seq[0](%u) + (%d) != (%u)\n" , |
| 1360 | "ipf_p_ftp_process" , t->ftps_seq[0], |
| 1361 | ackoff, thack); |
| 1362 | printf("%s:seq[0](%u) + (%d) != (%u)\n" , |
| 1363 | "ipf_p_ftp_process" , t->ftps_seq[1], |
| 1364 | ackoff, thack); |
| 1365 | } |
| 1366 | return APR_ERR(1); |
| 1367 | } |
| 1368 | |
| 1369 | if (softf->ipf_p_ftp_debug & DEBUG_PARSE) { |
| 1370 | printf("ipf_p_ftp_process:f:seq[0] %x seq[1] %x\n" , |
| 1371 | f->ftps_seq[0], f->ftps_seq[1]); |
| 1372 | } |
| 1373 | |
| 1374 | if (tcp->th_flags & TH_FIN) { |
| 1375 | if (thseq == f->ftps_seq[1]) { |
| 1376 | f->ftps_seq[0] = f->ftps_seq[1] - seqoff; |
| 1377 | f->ftps_seq[1] = thseq + 1 - seqoff; |
| 1378 | } else { |
| 1379 | DT2(thseq, ftpside_t *t, t, u_32_t, thseq); |
| 1380 | if (softf->ipf_p_ftp_debug & DEBUG_ERROR) { |
| 1381 | printf("FIN: thseq %x seqoff %d ftps_seq %x\n" , |
| 1382 | thseq, seqoff, f->ftps_seq[0]); |
| 1383 | } |
| 1384 | return APR_ERR(1); |
| 1385 | } |
| 1386 | } |
| 1387 | f->ftps_len = 0; |
| 1388 | return 0; |
| 1389 | } |
| 1390 | |
| 1391 | ok = 0; |
| 1392 | if ((thseq == f->ftps_seq[0]) || (thseq == f->ftps_seq[1])) { |
| 1393 | ok = 1; |
| 1394 | /* |
| 1395 | * Retransmitted data packet. |
| 1396 | */ |
| 1397 | } else if ((thseq + mlen == f->ftps_seq[0]) || |
| 1398 | (thseq + mlen == f->ftps_seq[1])) { |
| 1399 | ok = 1; |
| 1400 | } |
| 1401 | |
| 1402 | if (ok == 0) { |
| 1403 | DT3(ok_0, ftpside_t *, f, u_32_t, thseq, int, mlen); |
| 1404 | inc = thseq - f->ftps_seq[0]; |
| 1405 | if (softf->ipf_p_ftp_debug & DEBUG_ERROR) { |
| 1406 | printf("inc %d sel %d rv %d\n" , inc, sel, rv); |
| 1407 | printf("th_seq %x ftps_seq %x/%x\n" , |
| 1408 | thseq, f->ftps_seq[0], f->ftps_seq[1]); |
| 1409 | printf("ackmin %x ackoff %d\n" , aps->aps_ackmin[sel], |
| 1410 | aps->aps_ackoff[sel]); |
| 1411 | printf("seqmin %x seqoff %d\n" , aps->aps_seqmin[sel], |
| 1412 | aps->aps_seqoff[sel]); |
| 1413 | } |
| 1414 | |
| 1415 | return APR_ERR(1); |
| 1416 | } |
| 1417 | |
| 1418 | inc = 0; |
| 1419 | rptr = f->ftps_rptr; |
| 1420 | wptr = f->ftps_wptr; |
| 1421 | f->ftps_seq[0] = thseq; |
| 1422 | f->ftps_seq[1] = f->ftps_seq[0] + mlen; |
| 1423 | f->ftps_len = mlen; |
| 1424 | |
| 1425 | while (mlen > 0) { |
| 1426 | len = MIN(mlen, sizeof(f->ftps_buf) - (wptr - rptr)); |
| 1427 | if (len == 0) |
| 1428 | break; |
| 1429 | COPYDATA(m, off, len, wptr); |
| 1430 | mlen -= len; |
| 1431 | off += len; |
| 1432 | wptr += len; |
| 1433 | |
| 1434 | whilemore: |
| 1435 | if (softf->ipf_p_ftp_debug & DEBUG_PARSE) |
| 1436 | printf("%s:len %d/%d off %d wptr %lx junk %d [%*.*s]\n" , |
| 1437 | "ipf_p_ftp_process" , |
| 1438 | len, mlen, off, (u_long)wptr, f->ftps_junk, |
| 1439 | len, len, rptr); |
| 1440 | |
| 1441 | f->ftps_wptr = wptr; |
| 1442 | if (f->ftps_junk != FTPXY_JUNK_OK) { |
| 1443 | i = f->ftps_junk; |
| 1444 | f->ftps_junk = ipf_p_ftp_valid(softf, ftp, rv, rptr, |
| 1445 | wptr - rptr); |
| 1446 | DT2(junk_transit, int, i, int, f->ftps_junk); |
| 1447 | |
| 1448 | if (softf->ipf_p_ftp_debug & DEBUG_PARSE) |
| 1449 | printf("%s:junk %d -> %d\n" , |
| 1450 | "ipf_p_ftp_process" , i, f->ftps_junk); |
| 1451 | |
| 1452 | if (f->ftps_junk == FTPXY_JUNK_BAD) { |
| 1453 | DT(buffer_full); |
| 1454 | if (wptr - rptr == sizeof(f->ftps_buf)) { |
| 1455 | if (softf->ipf_p_ftp_debug & |
| 1456 | DEBUG_PARSE_INFO) |
| 1457 | printf("%s:full buffer\n" , |
| 1458 | "ipf_p_ftp_process" ); |
| 1459 | f->ftps_rptr = f->ftps_buf; |
| 1460 | f->ftps_wptr = f->ftps_buf; |
| 1461 | rptr = f->ftps_rptr; |
| 1462 | wptr = f->ftps_wptr; |
| 1463 | continue; |
| 1464 | } |
| 1465 | } |
| 1466 | } |
| 1467 | |
| 1468 | while ((f->ftps_junk == FTPXY_JUNK_OK) && (wptr > rptr)) { |
| 1469 | len = wptr - rptr; |
| 1470 | f->ftps_junk = ipf_p_ftp_valid(softf, ftp, rv, |
| 1471 | rptr, len); |
| 1472 | |
| 1473 | if (softf->ipf_p_ftp_debug & DEBUG_PARSE) { |
| 1474 | printf("%s=%d len %d rv %d ptr %lx/%lx " , |
| 1475 | "ipf_p_ftp_valid" , |
| 1476 | f->ftps_junk, len, rv, (u_long)rptr, |
| 1477 | (u_long)wptr); |
| 1478 | printf("buf [%*.*s]\n" , len, len, rptr); |
| 1479 | } |
| 1480 | |
| 1481 | if (f->ftps_junk == FTPXY_JUNK_OK) { |
| 1482 | f->ftps_cmds++; |
| 1483 | f->ftps_rptr = rptr; |
| 1484 | if (rv) |
| 1485 | inc += ipf_p_ftp_server(softf, fin, ip, |
| 1486 | nat, ftp, len); |
| 1487 | else |
| 1488 | inc += ipf_p_ftp_client(softf, fin, ip, |
| 1489 | nat, ftp, len); |
| 1490 | rptr = f->ftps_rptr; |
| 1491 | wptr = f->ftps_wptr; |
| 1492 | } |
| 1493 | } |
| 1494 | |
| 1495 | /* |
| 1496 | * Off to a bad start so lets just forget about using the |
| 1497 | * ftp proxy for this connection. |
| 1498 | */ |
| 1499 | if ((f->ftps_cmds == 0) && (f->ftps_junk == FTPXY_JUNK_BAD)) { |
| 1500 | /* f->ftps_seq[1] += inc; */ |
| 1501 | |
| 1502 | DT(ftp_junk_cmd); |
| 1503 | if (softf->ipf_p_ftp_debug & DEBUG_ERROR) |
| 1504 | printf("%s:cmds == 0 junk == 1\n" , |
| 1505 | "ipf_p_ftp_process" ); |
| 1506 | return APR_ERR(2); |
| 1507 | } |
| 1508 | |
| 1509 | retry = 0; |
| 1510 | if ((f->ftps_junk != FTPXY_JUNK_OK) && (rptr < wptr)) { |
| 1511 | for (s = rptr; s < wptr; s++) { |
| 1512 | if ((*s == '\r') && (s + 1 < wptr) && |
| 1513 | (*(s + 1) == '\n')) { |
| 1514 | rptr = s + 2; |
| 1515 | retry = 1; |
| 1516 | if (f->ftps_junk != FTPXY_JUNK_CONT) |
| 1517 | f->ftps_junk = FTPXY_JUNK_OK; |
| 1518 | break; |
| 1519 | } |
| 1520 | } |
| 1521 | } |
| 1522 | |
| 1523 | if (rptr == wptr) { |
| 1524 | rptr = wptr = f->ftps_buf; |
| 1525 | } else { |
| 1526 | /* |
| 1527 | * Compact the buffer back to the start. The junk |
| 1528 | * flag should already be set and because we're not |
| 1529 | * throwing away any data, it is preserved from its |
| 1530 | * current state. |
| 1531 | */ |
| 1532 | if (rptr > f->ftps_buf) { |
| 1533 | bcopy(rptr, f->ftps_buf, wptr - rptr); |
| 1534 | wptr -= rptr - f->ftps_buf; |
| 1535 | rptr = f->ftps_buf; |
| 1536 | } |
| 1537 | } |
| 1538 | f->ftps_rptr = rptr; |
| 1539 | f->ftps_wptr = wptr; |
| 1540 | if (retry) |
| 1541 | goto whilemore; |
| 1542 | } |
| 1543 | |
| 1544 | /* f->ftps_seq[1] += inc; */ |
| 1545 | if (tcp->th_flags & TH_FIN) |
| 1546 | f->ftps_seq[1]++; |
| 1547 | if (softf->ipf_p_ftp_debug & DEBUG_PARSE_INFO) { |
| 1548 | #ifdef __sgi |
| 1549 | mlen = fin->fin_plen; |
| 1550 | #else |
| 1551 | mlen = MSGDSIZE(m); |
| 1552 | #endif |
| 1553 | mlen -= off; |
| 1554 | printf("ftps_seq[1] = %x inc %d len %d\n" , |
| 1555 | f->ftps_seq[1], inc, mlen); |
| 1556 | } |
| 1557 | |
| 1558 | f->ftps_rptr = rptr; |
| 1559 | f->ftps_wptr = wptr; |
| 1560 | return APR_INC(inc); |
| 1561 | } |
| 1562 | |
| 1563 | |
| 1564 | int |
| 1565 | ipf_p_ftp_out(void *arg, fr_info_t *fin, ap_session_t *aps, nat_t *nat) |
| 1566 | { |
| 1567 | ipf_ftp_softc_t *softf = arg; |
| 1568 | ftpinfo_t *ftp; |
| 1569 | int rev; |
| 1570 | |
| 1571 | ftp = aps->aps_data; |
| 1572 | if (ftp == NULL) |
| 1573 | return 0; |
| 1574 | |
| 1575 | rev = (nat->nat_dir == NAT_OUTBOUND) ? 0 : 1; |
| 1576 | if (ftp->ftp_side[1 - rev].ftps_ifp == NULL) |
| 1577 | ftp->ftp_side[1 - rev].ftps_ifp = fin->fin_ifp; |
| 1578 | |
| 1579 | return ipf_p_ftp_process(softf, fin, nat, ftp, rev); |
| 1580 | } |
| 1581 | |
| 1582 | |
| 1583 | int |
| 1584 | ipf_p_ftp_in(void *arg, fr_info_t *fin, ap_session_t *aps, nat_t *nat) |
| 1585 | { |
| 1586 | ipf_ftp_softc_t *softf = arg; |
| 1587 | ftpinfo_t *ftp; |
| 1588 | int rev; |
| 1589 | |
| 1590 | ftp = aps->aps_data; |
| 1591 | if (ftp == NULL) |
| 1592 | return 0; |
| 1593 | |
| 1594 | rev = (nat->nat_dir == NAT_OUTBOUND) ? 0 : 1; |
| 1595 | if (ftp->ftp_side[rev].ftps_ifp == NULL) |
| 1596 | ftp->ftp_side[rev].ftps_ifp = fin->fin_ifp; |
| 1597 | |
| 1598 | return ipf_p_ftp_process(softf, fin, nat, ftp, 1 - rev); |
| 1599 | } |
| 1600 | |
| 1601 | |
| 1602 | /* |
| 1603 | * ipf_p_ftp_atoi - implement a version of atoi which processes numbers in |
| 1604 | * pairs separated by commas (which are expected to be in the range 0 - 255), |
| 1605 | * returning a 16 bit number combining either side of the , as the MSB and |
| 1606 | * LSB. |
| 1607 | */ |
| 1608 | u_short |
| 1609 | ipf_p_ftp_atoi(char **ptr) |
| 1610 | { |
| 1611 | register char *s = *ptr, c; |
| 1612 | register u_char i = 0, j = 0; |
| 1613 | |
| 1614 | while (((c = *s++) != '\0') && ISDIGIT(c)) { |
| 1615 | i *= 10; |
| 1616 | i += c - '0'; |
| 1617 | } |
| 1618 | if (c != ',') { |
| 1619 | *ptr = NULL; |
| 1620 | return 0; |
| 1621 | } |
| 1622 | while (((c = *s++) != '\0') && ISDIGIT(c)) { |
| 1623 | j *= 10; |
| 1624 | j += c - '0'; |
| 1625 | } |
| 1626 | *ptr = s; |
| 1627 | i &= 0xff; |
| 1628 | j &= 0xff; |
| 1629 | return (i << 8) | j; |
| 1630 | } |
| 1631 | |
| 1632 | |
| 1633 | int |
| 1634 | ipf_p_ftp_eprt(ipf_ftp_softc_t *softf, fr_info_t *fin, ip_t *ip, nat_t *nat, |
| 1635 | ftpinfo_t *ftp, int dlen) |
| 1636 | { |
| 1637 | ftpside_t *f; |
| 1638 | |
| 1639 | /* |
| 1640 | * Check for client sending out EPRT message. |
| 1641 | */ |
| 1642 | if (dlen < IPF_MINEPRTLEN) { |
| 1643 | DT1(epert_dlen, int, dlen); |
| 1644 | if (softf->ipf_p_ftp_debug & DEBUG_PARSE_ERR) |
| 1645 | printf("ipf_p_ftp_eprt:dlen(%d) < IPF_MINEPRTLEN\n" , |
| 1646 | dlen); |
| 1647 | return 0; |
| 1648 | } |
| 1649 | |
| 1650 | /* |
| 1651 | * Parse the EPRT command. Format is: |
| 1652 | * "EPRT |1|1.2.3.4|2000|" for IPv4 and |
| 1653 | * "EPRT |2|ef00::1:2|2000|" for IPv6 |
| 1654 | */ |
| 1655 | f = &ftp->ftp_side[0]; |
| 1656 | if (f->ftps_rptr[5] != '|') |
| 1657 | return 0; |
| 1658 | if (f->ftps_rptr[5] == f->ftps_rptr[7]) { |
| 1659 | if (f->ftps_rptr[6] == '1' && nat->nat_v[0] == 4) |
| 1660 | return ipf_p_ftp_eprt4(softf, fin, ip, nat, ftp, dlen); |
| 1661 | #ifdef USE_INET6 |
| 1662 | if (f->ftps_rptr[6] == '2' && nat->nat_v[0] == 6) |
| 1663 | return ipf_p_ftp_eprt6(softf, fin, ip, nat, ftp, dlen); |
| 1664 | #endif |
| 1665 | } |
| 1666 | return 0; |
| 1667 | } |
| 1668 | |
| 1669 | |
| 1670 | int |
| 1671 | ipf_p_ftp_eprt4(ipf_ftp_softc_t *softf, fr_info_t *fin, ip_t *ip, nat_t *nat, |
| 1672 | ftpinfo_t *ftp, int dlen) |
| 1673 | { |
| 1674 | int a1, a2, a3, a4, port, olen, nlen, inc, off; |
| 1675 | char newbuf[IPF_FTPBUFSZ]; |
| 1676 | char *s, c, delim; |
| 1677 | u_32_t addr, i; |
| 1678 | tcphdr_t *tcp; |
| 1679 | ftpside_t *f; |
| 1680 | mb_t *m; |
| 1681 | |
| 1682 | m = fin->fin_m; |
| 1683 | tcp = (tcphdr_t *)fin->fin_dp; |
| 1684 | off = (char *)tcp - (char *)ip + (TCP_OFF(tcp) << 2) + fin->fin_ipoff; |
| 1685 | f = &ftp->ftp_side[0]; |
| 1686 | delim = f->ftps_rptr[5]; |
| 1687 | s = f->ftps_rptr + 8; |
| 1688 | |
| 1689 | /* |
| 1690 | * get the IP address. |
| 1691 | */ |
| 1692 | i = 0; |
| 1693 | while (((c = *s++) != '\0') && ISDIGIT(c)) { |
| 1694 | i *= 10; |
| 1695 | i += c - '0'; |
| 1696 | } |
| 1697 | if (i > 255) |
| 1698 | return 0; |
| 1699 | if (c != '.') |
| 1700 | return 0; |
| 1701 | addr = (i << 24); |
| 1702 | |
| 1703 | i = 0; |
| 1704 | while (((c = *s++) != '\0') && ISDIGIT(c)) { |
| 1705 | i *= 10; |
| 1706 | i += c - '0'; |
| 1707 | } |
| 1708 | if (i > 255) |
| 1709 | return 0; |
| 1710 | if (c != '.') |
| 1711 | return 0; |
| 1712 | addr |= (addr << 16); |
| 1713 | |
| 1714 | i = 0; |
| 1715 | while (((c = *s++) != '\0') && ISDIGIT(c)) { |
| 1716 | i *= 10; |
| 1717 | i += c - '0'; |
| 1718 | } |
| 1719 | if (i > 255) |
| 1720 | return 0; |
| 1721 | if (c != '.') |
| 1722 | return 0; |
| 1723 | addr |= (addr << 8); |
| 1724 | |
| 1725 | i = 0; |
| 1726 | while (((c = *s++) != '\0') && ISDIGIT(c)) { |
| 1727 | i *= 10; |
| 1728 | i += c - '0'; |
| 1729 | } |
| 1730 | if (i > 255) |
| 1731 | return 0; |
| 1732 | if (c != delim) |
| 1733 | return 0; |
| 1734 | addr |= addr; |
| 1735 | |
| 1736 | /* |
| 1737 | * Get the port number |
| 1738 | */ |
| 1739 | i = 0; |
| 1740 | while (((c = *s++) != '\0') && ISDIGIT(c)) { |
| 1741 | i *= 10; |
| 1742 | i += c - '0'; |
| 1743 | } |
| 1744 | if (i > 65535) |
| 1745 | return 0; |
| 1746 | if (c != delim) |
| 1747 | return 0; |
| 1748 | port = i; |
| 1749 | |
| 1750 | /* |
| 1751 | * Check for CR-LF at the end of the command string. |
| 1752 | */ |
| 1753 | if ((*s != '\r') || (*(s + 1) != '\n')) { |
| 1754 | DT(eprt4_no_crlf); |
| 1755 | if (softf->ipf_p_ftp_debug & DEBUG_PARSE_ERR) |
| 1756 | printf("ipf_p_ftp_eprt4:missing %s\n" , "cr-lf" ); |
| 1757 | return 0; |
| 1758 | } |
| 1759 | s += 2; |
| 1760 | |
| 1761 | /* |
| 1762 | * Calculate new address parts for PORT command |
| 1763 | */ |
| 1764 | if (nat->nat_dir == NAT_INBOUND) |
| 1765 | a1 = ntohl(nat->nat_odstaddr); |
| 1766 | else |
| 1767 | a1 = ntohl(ip->ip_src.s_addr); |
| 1768 | a2 = (a1 >> 16) & 0xff; |
| 1769 | a3 = (a1 >> 8) & 0xff; |
| 1770 | a4 = a1 & 0xff; |
| 1771 | a1 >>= 24; |
| 1772 | olen = s - f->ftps_rptr; |
| 1773 | /* |
| 1774 | * While we could force the use of | as a delimiter here, it makes |
| 1775 | * sense to preserve whatever character is being used by the systems |
| 1776 | * involved in the communication. |
| 1777 | */ |
| 1778 | snprintf(newbuf, sizeof(newbuf), "%s %c1%c%u.%u.%u.%u%c%u%c\r\n" , |
| 1779 | "EPRT" , delim, delim, a1, a2, a3, a4, delim, port, delim); |
| 1780 | |
| 1781 | nlen = strlen(newbuf); |
| 1782 | inc = nlen - olen; |
| 1783 | if ((inc + fin->fin_plen) > 65535) { |
| 1784 | DT2(eprt4_len, int, inc, int, fin->fin_plen); |
| 1785 | if (softf->ipf_p_ftp_debug & DEBUG_ERROR) |
| 1786 | printf("ipf_p_ftp_eprt4:inc(%d) + ip->ip_len > 65535\n" , |
| 1787 | inc); |
| 1788 | return 0; |
| 1789 | } |
| 1790 | |
| 1791 | off = (char *)tcp - (char *)ip + (TCP_OFF(tcp) << 2) + fin->fin_ipoff; |
| 1792 | #if !defined(_KERNEL) |
| 1793 | M_ADJ(m, inc); |
| 1794 | #else |
| 1795 | if (inc < 0) |
| 1796 | M_ADJ(m, inc); |
| 1797 | #endif |
| 1798 | /* the mbuf chain will be extended if necessary by m_copyback() */ |
| 1799 | COPYBACK(m, off, nlen, newbuf); |
| 1800 | fin->fin_flx |= FI_DOCKSUM; |
| 1801 | |
| 1802 | if (inc != 0) { |
| 1803 | fin->fin_plen += inc; |
| 1804 | ip->ip_len = htons(fin->fin_plen); |
| 1805 | fin->fin_dlen += inc; |
| 1806 | } |
| 1807 | |
| 1808 | f->ftps_cmd = FTPXY_C_EPRT; |
| 1809 | return ipf_p_ftp_addport(softf, fin, ip, nat, ftp, dlen, port, inc); |
| 1810 | } |
| 1811 | |
| 1812 | |
| 1813 | int |
| 1814 | ipf_p_ftp_epsv(ipf_ftp_softc_t *softf, fr_info_t *fin, ip_t *ip, nat_t *nat, |
| 1815 | ftpinfo_t *ftp, int dlen) |
| 1816 | { |
| 1817 | char newbuf[IPF_FTPBUFSZ]; |
| 1818 | u_short ap = 0; |
| 1819 | ftpside_t *f; |
| 1820 | char *s; |
| 1821 | |
| 1822 | if ((softf->ipf_p_ftp_forcepasv != 0) && |
| 1823 | (ftp->ftp_side[0].ftps_cmd != FTPXY_C_EPSV)) { |
| 1824 | DT1(epsv_cmd, int, ftp->ftp_side[0].ftps_cmd); |
| 1825 | if (softf->ipf_p_ftp_debug & DEBUG_PARSE_ERR) |
| 1826 | printf("ipf_p_ftp_epsv:ftps_cmd(%d) != FTPXY_C_EPSV\n" , |
| 1827 | ftp->ftp_side[0].ftps_cmd); |
| 1828 | return 0; |
| 1829 | } |
| 1830 | f = &ftp->ftp_side[1]; |
| 1831 | |
| 1832 | #define EPSV_REPLEN 33 |
| 1833 | /* |
| 1834 | * Check for EPSV reply message. |
| 1835 | */ |
| 1836 | if (dlen < IPF_MIN229LEN) { |
| 1837 | return (0); |
| 1838 | } else if (strncmp(f->ftps_rptr, |
| 1839 | "229 Entering Extended Passive Mode" , EPSV_REPLEN)) { |
| 1840 | return (0); |
| 1841 | } |
| 1842 | |
| 1843 | /* |
| 1844 | * Skip the EPSV command + space |
| 1845 | */ |
| 1846 | s = f->ftps_rptr + 33; |
| 1847 | while (*s && !ISDIGIT(*s)) |
| 1848 | s++; |
| 1849 | |
| 1850 | /* |
| 1851 | * As per RFC 2428, there are no addres components in the EPSV |
| 1852 | * response. So we'll go straight to getting the port. |
| 1853 | */ |
| 1854 | while (*s && ISDIGIT(*s)) { |
| 1855 | ap *= 10; |
| 1856 | ap += *s++ - '0'; |
| 1857 | } |
| 1858 | |
| 1859 | if (!s) { |
| 1860 | return 0; |
| 1861 | } |
| 1862 | |
| 1863 | if (*s == '|') |
| 1864 | s++; |
| 1865 | if (*s == ')') |
| 1866 | s++; |
| 1867 | if (*s == '\n') |
| 1868 | s--; |
| 1869 | /* |
| 1870 | * check for CR-LF at the end. |
| 1871 | */ |
| 1872 | if ((*s != '\r') || (*(s + 1) != '\n')) { |
| 1873 | return 0; |
| 1874 | } |
| 1875 | s += 2; |
| 1876 | |
| 1877 | snprintf(newbuf, sizeof(newbuf), "%s (|||%u|)\r\n" , |
| 1878 | "229 Entering Extended Passive Mode" , ap); |
| 1879 | |
| 1880 | return ipf_p_ftp_pasvreply(softf, fin, ip, nat, ftp, (u_int)ap, |
| 1881 | newbuf, s); |
| 1882 | } |
| 1883 | |
| 1884 | #ifdef USE_INET6 |
| 1885 | int |
| 1886 | ipf_p_ftp_eprt6(ipf_ftp_softc_t *softf, fr_info_t *fin, ip_t *ip, |
| 1887 | nat_t *nat, ftpinfo_t *ftp, int dlen) |
| 1888 | { |
| 1889 | int port, olen, nlen, inc, off, left, i; |
| 1890 | char newbuf[IPF_FTPBUFSZ]; |
| 1891 | char *s, c; |
| 1892 | i6addr_t addr, *a6; |
| 1893 | tcphdr_t *tcp; |
| 1894 | ip6_t *ip6; |
| 1895 | char delim; |
| 1896 | u_short whole; |
| 1897 | u_short part; |
| 1898 | ftpside_t *f; |
| 1899 | u_short *t; |
| 1900 | int fwd; |
| 1901 | mb_t *m; |
| 1902 | u_32_t a; |
| 1903 | |
| 1904 | m = fin->fin_m; |
| 1905 | ip6 = (ip6_t *)ip; |
| 1906 | f = &ftp->ftp_side[0]; |
| 1907 | s = f->ftps_rptr + 8; |
| 1908 | f = &ftp->ftp_side[0]; |
| 1909 | delim = f->ftps_rptr[5]; |
| 1910 | tcp = (tcphdr_t *)fin->fin_dp; |
| 1911 | off = (char *)tcp - (char *)ip + (TCP_OFF(tcp) << 2) + fin->fin_ipoff; |
| 1912 | |
| 1913 | addr.i6[0] = 0; |
| 1914 | addr.i6[1] = 0; |
| 1915 | addr.i6[2] = 0; |
| 1916 | addr.i6[3] = 0; |
| 1917 | /* |
| 1918 | * Parse an IPv6 address. |
| 1919 | * Go forward until either :: or | is found. If :: is found, |
| 1920 | * reverse direction. Direction change is performed to ease |
| 1921 | * parsing an unknown number of 0s in the middle. |
| 1922 | */ |
| 1923 | whole = 0; |
| 1924 | t = (u_short *)&addr; |
| 1925 | fwd = 1; |
| 1926 | for (part = 0; (c = *s) != '\0'; ) { |
| 1927 | if (c == delim) { |
| 1928 | *t = htons((u_short)whole); |
| 1929 | break; |
| 1930 | } |
| 1931 | if (c == ':') { |
| 1932 | *t = part; |
| 1933 | if (fwd) { |
| 1934 | *t = htons((u_short)whole); |
| 1935 | t++; |
| 1936 | } else { |
| 1937 | *t = htons((u_short)(whole >> 16)); |
| 1938 | t--; |
| 1939 | } |
| 1940 | whole = 0; |
| 1941 | if (fwd == 1 && s[1] == ':') { |
| 1942 | while (*s && *s != '|') |
| 1943 | s++; |
| 1944 | if ((c = *s) != delim) |
| 1945 | break; |
| 1946 | t = (u_short *)&addr.i6[3]; |
| 1947 | t++; |
| 1948 | fwd = 0; |
| 1949 | } else if (fwd == 0 && s[-1] == ':') { |
| 1950 | break; |
| 1951 | } |
| 1952 | } else { |
| 1953 | if (c >= '0' && c <= '9') { |
| 1954 | c -= '0'; |
| 1955 | } else if (c >= 'a' && c <= 'f') { |
| 1956 | c -= 'a' + 10; |
| 1957 | } else if (c >= 'A' && c <= 'F') { |
| 1958 | c -= 'A' + 10; |
| 1959 | } |
| 1960 | if (fwd) { |
| 1961 | whole <<= 8; |
| 1962 | whole |= c; |
| 1963 | } else { |
| 1964 | whole >>= 8; |
| 1965 | whole |= ((u_32_t)c) << 24; |
| 1966 | } |
| 1967 | } |
| 1968 | if (fwd) |
| 1969 | s++; |
| 1970 | else |
| 1971 | s--; |
| 1972 | } |
| 1973 | if (c != ':' && c != delim) |
| 1974 | return 0; |
| 1975 | |
| 1976 | while (*s != '|') |
| 1977 | s++; |
| 1978 | s++; |
| 1979 | |
| 1980 | /* |
| 1981 | * Get the port number |
| 1982 | */ |
| 1983 | i = 0; |
| 1984 | while (((c = *s++) != '\0') && ISDIGIT(c)) { |
| 1985 | i *= 10; |
| 1986 | i += c - '0'; |
| 1987 | } |
| 1988 | if (i > 65535) |
| 1989 | return 0; |
| 1990 | if (c != delim) |
| 1991 | return 0; |
| 1992 | port = (u_short)(i & 0xffff); |
| 1993 | |
| 1994 | /* |
| 1995 | * Check for CR-LF at the end of the command string. |
| 1996 | */ |
| 1997 | if ((*s != '\r') || (*(s + 1) != '\n')) { |
| 1998 | DT(eprt6_no_crlf); |
| 1999 | if (softf->ipf_p_ftp_debug & DEBUG_PARSE_ERR) |
| 2000 | printf("ipf_p_ftp_eprt6:missing %s\n" , "cr-lf" ); |
| 2001 | return 0; |
| 2002 | } |
| 2003 | s += 2; |
| 2004 | |
| 2005 | /* |
| 2006 | * Calculate new address parts for PORT command |
| 2007 | */ |
| 2008 | a6 = (i6addr_t *)&ip6->ip6_src; |
| 2009 | olen = s - f->ftps_rptr; |
| 2010 | /* DO NOT change this to snprintf! */ |
| 2011 | /* |
| 2012 | * While we could force the use of | as a delimiter here, it makes |
| 2013 | * sense to preserve whatever character is being used by the systems |
| 2014 | * involved in the communication. |
| 2015 | */ |
| 2016 | s = newbuf; |
| 2017 | left = sizeof(newbuf); |
| 2018 | snprintf(newbuf, left, "EPRT %c2%c" , delim, delim); |
| 2019 | left -= strlen(s) + 1; |
| 2020 | s += strlen(s); |
| 2021 | a = ntohl(a6->i6[0]); |
| 2022 | snprintf(s, left, "%x:%x:" , a >> 16, a & 0xffff); |
| 2023 | left -= strlen(s); |
| 2024 | s += strlen(s); |
| 2025 | a = ntohl(a6->i6[1]); |
| 2026 | snprintf(s, left, "%x:%x:" , a >> 16, a & 0xffff); |
| 2027 | left -= strlen(s); |
| 2028 | s += strlen(s); |
| 2029 | a = ntohl(a6->i6[2]); |
| 2030 | snprintf(s, left, "%x:%x:" , a >> 16, a & 0xffff); |
| 2031 | left -= strlen(s); |
| 2032 | s += strlen(s); |
| 2033 | a = ntohl(a6->i6[3]); |
| 2034 | snprintf(s, left, "%x:%x" , a >> 16, a & 0xffff); |
| 2035 | left -= strlen(s); |
| 2036 | s += strlen(s); |
| 2037 | snprintf(s, left, "|%d|\r\n" , port); |
| 2038 | nlen = strlen(newbuf); |
| 2039 | inc = nlen - olen; |
| 2040 | if ((inc + fin->fin_plen) > 65535) { |
| 2041 | DT2(eprt6_len, int, inc, int, fin->fin_plen); |
| 2042 | if (softf->ipf_p_ftp_debug & DEBUG_ERROR) |
| 2043 | printf("ipf_p_ftp_eprt6:inc(%d) + ip->ip_len > 65535\n" , |
| 2044 | inc); |
| 2045 | return 0; |
| 2046 | } |
| 2047 | |
| 2048 | off = (char *)tcp - (char *)ip + (TCP_OFF(tcp) << 2) + fin->fin_ipoff; |
| 2049 | #if !defined(_KERNEL) |
| 2050 | M_ADJ(m, inc); |
| 2051 | #else |
| 2052 | if (inc < 0) |
| 2053 | M_ADJ(m, inc); |
| 2054 | #endif |
| 2055 | /* the mbuf chain will be extended if necessary by m_copyback() */ |
| 2056 | COPYBACK(m, off, nlen, newbuf); |
| 2057 | fin->fin_flx |= FI_DOCKSUM; |
| 2058 | |
| 2059 | if (inc != 0) { |
| 2060 | fin->fin_plen += inc; |
| 2061 | ip6->ip6_plen = htons(fin->fin_plen - fin->fin_hlen); |
| 2062 | fin->fin_dlen += inc; |
| 2063 | } |
| 2064 | |
| 2065 | f->ftps_cmd = FTPXY_C_EPRT; |
| 2066 | return ipf_p_ftp_addport(softf, fin, ip, nat, ftp, dlen, port, inc); |
| 2067 | } |
| 2068 | #endif /* USE_INET6 */ |
| 2069 | |