/*- * Copyright (c) 2002-2009 Luigi Rizzo, Universita` di Pisa * * Supported by: Valeria Paoli * * Redistribution and use in source and binary forms, with or without * modification, are permitted provided that the following conditions * are met: * 1. Redistributions of source code must retain the above copyright * notice, this list of conditions and the following disclaimer. * 2. Redistributions in binary form must reproduce the above copyright * notice, this list of conditions and the following disclaimer in the * documentation and/or other materials provided with the distribution. * * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF * SUCH DAMAGE. */ #include __FBSDID("$FreeBSD$"); /* * Sockopt support for ipfw. The routines here implement * the upper half of the ipfw code. */ #include "opt_ipfw.h" #include "opt_inet.h" #ifndef INET #error IPFIREWALL requires INET. #endif /* INET */ #include "opt_inet6.h" #include #include #include #include /* struct m_tag used by nested headers */ #include #include #include #include #include #include #include #include #include #include #include #include #include #include /* hooks */ #include #include #ifdef MAC #include #endif MALLOC_DEFINE(M_IPFW, "IpFw/IpAcct", "IpFw/IpAcct chain's"); /* * static variables followed by global ones (none in this file) */ /* * Find the smallest rule >= key, id. * We could use bsearch but it is so simple that we code it directly */ int ipfw_find_rule(struct ip_fw_chain *chain, uint32_t key, uint32_t id) { int i, lo, hi; struct ip_fw *r; for (lo = 0, hi = chain->n_rules - 1; lo < hi;) { i = (lo + hi) / 2; r = chain->map[i]; if (r->rulenum < key) lo = i + 1; /* continue from the next one */ else if (r->rulenum > key) hi = i; /* this might be good */ else if (r->id < id) lo = i + 1; /* continue from the next one */ else /* r->id >= id */ hi = i; /* this might be good */ }; return hi; } /* * allocate a new map, returns the chain locked. extra is the number * of entries to add or delete. */ static struct ip_fw ** get_map(struct ip_fw_chain *chain, int extra, int locked) { for (;;) { struct ip_fw **map; int i; i = chain->n_rules + extra; map = malloc(i * sizeof(struct ip_fw *), M_IPFW, locked ? M_NOWAIT : M_WAITOK); if (map == NULL) { printf("%s: cannot allocate map\n", __FUNCTION__); return NULL; } if (!locked) IPFW_UH_WLOCK(chain); if (i >= chain->n_rules + extra) /* good */ return map; /* otherwise we lost the race, free and retry */ if (!locked) IPFW_UH_WUNLOCK(chain); free(map, M_IPFW); } } /* * swap the maps. It is supposed to be called with IPFW_UH_WLOCK */ static struct ip_fw ** swap_map(struct ip_fw_chain *chain, struct ip_fw **new_map, int new_len) { struct ip_fw **old_map; IPFW_WLOCK(chain); chain->id++; chain->n_rules = new_len; old_map = chain->map; chain->map = new_map; IPFW_WUNLOCK(chain); return old_map; } /* * Add a new rule to the list. Copy the rule into a malloc'ed area, then * possibly create a rule number and add the rule to the list. * Update the rule_number in the input struct so the caller knows it as well. * XXX DO NOT USE FOR THE DEFAULT RULE. * Must be called without IPFW_UH held */ int ipfw_add_rule(struct ip_fw_chain *chain, struct ip_fw *input_rule) { struct ip_fw *rule; int i, l, insert_before; struct ip_fw **map; /* the new array of pointers */ if (chain->rules == NULL || input_rule->rulenum > IPFW_DEFAULT_RULE-1) return (EINVAL); l = RULESIZE(input_rule); rule = malloc(l, M_IPFW, M_WAITOK | M_ZERO); /* get_map returns with IPFW_UH_WLOCK if successful */ map = get_map(chain, 1, 0 /* not locked */); if (map == NULL) { free(rule, M_IPFW); return ENOSPC; } bcopy(input_rule, rule, l); /* clear fields not settable from userland */ rule->x_next = NULL; rule->next_rule = NULL; IPFW_ZERO_RULE_COUNTER(rule); if (V_autoinc_step < 1) V_autoinc_step = 1; else if (V_autoinc_step > 1000) V_autoinc_step = 1000; /* find the insertion point, we will insert before */ insert_before = rule->rulenum ? rule->rulenum + 1 : IPFW_DEFAULT_RULE; i = ipfw_find_rule(chain, insert_before, 0); /* duplicate first part */ if (i > 0) bcopy(chain->map, map, i * sizeof(struct ip_fw *)); map[i] = rule; /* duplicate remaining part, we always have the default rule */ bcopy(chain->map + i, map + i + 1, sizeof(struct ip_fw *) *(chain->n_rules - i)); if (rule->rulenum == 0) { /* write back the number */ rule->rulenum = i > 0 ? map[i-1]->rulenum : 0; if (rule->rulenum < IPFW_DEFAULT_RULE - V_autoinc_step) rule->rulenum += V_autoinc_step; input_rule->rulenum = rule->rulenum; } rule->id = chain->id + 1; map = swap_map(chain, map, chain->n_rules + 1); chain->static_len += l; IPFW_UH_WUNLOCK(chain); if (map) free(map, M_IPFW); return (0); } /* * Reclaim storage associated with a list of rules. This is * typically the list created using remove_rule. * A NULL pointer on input is handled correctly. */ void ipfw_reap_rules(struct ip_fw *head) { struct ip_fw *rule; while ((rule = head) != NULL) { head = head->x_next; free(rule, M_IPFW); } } /* * Used by del_entry() to check if a rule should be kept. * Returns 1 if the rule must be kept, 0 otherwise. * * Called with cmd = {0,1,5}. * cmd == 0 matches on rule numbers, excludes rules in RESVD_SET if n == 0 ; * cmd == 1 matches on set numbers only, rule numbers are ignored; * cmd == 5 matches on rule and set numbers. * * n == 0 is a wildcard for rule numbers, there is no wildcard for sets. * * Rules to keep are * (default || reserved || !match_set || !match_number) * where * default ::= (rule->rulenum == IPFW_DEFAULT_RULE) * // the default rule is always protected * * reserved ::= (cmd == 0 && n == 0 && rule->set == RESVD_SET) * // RESVD_SET is protected only if cmd == 0 and n == 0 ("ipfw flush") * * match_set ::= (cmd == 0 || rule->set == set) * // set number is ignored for cmd == 0 * * match_number ::= (cmd == 1 || n == 0 || n == rule->rulenum) * // number is ignored for cmd == 1 or n == 0 * */ static int keep_rule(struct ip_fw *rule, uint8_t cmd, uint8_t set, uint32_t n) { return (rule->rulenum == IPFW_DEFAULT_RULE) || (cmd == 0 && n == 0 && rule->set == RESVD_SET) || !(cmd == 0 || rule->set == set) || !(cmd == 1 || n == 0 || n == rule->rulenum); } /** * Remove all rules with given number, or do set manipulation. * Assumes chain != NULL && *chain != NULL. * * The argument is an uint32_t. The low 16 bit are the rule or set number; * the next 8 bits are the new set; the top 8 bits indicate the command: * * 0 delete rules numbered "rulenum" * 1 delete rules in set "rulenum" * 2 move rules "rulenum" to set "new_set" * 3 move rules from set "rulenum" to set "new_set" * 4 swap sets "rulenum" and "new_set" * 5 delete rules "rulenum" and set "new_set" */ static int del_entry(struct ip_fw_chain *chain, uint32_t arg) { struct ip_fw *rule; uint32_t num; /* rule number or old_set */ uint8_t cmd, new_set; int start, end, i, ofs, n; struct ip_fw **map = NULL; int error = 0; num = arg & 0xffff; cmd = (arg >> 24) & 0xff; new_set = (arg >> 16) & 0xff; if (cmd > 5 || new_set > RESVD_SET) return EINVAL; if (cmd == 0 || cmd == 2 || cmd == 5) { if (num >= IPFW_DEFAULT_RULE) return EINVAL; } else { if (num > RESVD_SET) /* old_set */ return EINVAL; } IPFW_UH_WLOCK(chain); /* arbitrate writers */ chain->reap = NULL; /* prepare for deletions */ switch (cmd) { case 0: /* delete rules "num" (num == 0 matches all) */ case 1: /* delete all rules in set N */ case 5: /* delete rules with number N and set "new_set". */ /* * Locate first rule to delete (start), the rule after * the last one to delete (end), and count how many * rules to delete (n). Always use keep_rule() to * determine which rules to keep. */ n = 0; if (cmd == 1) { /* look for a specific set including RESVD_SET. * Must scan the entire range, ignore num. */ new_set = num; for (start = -1, end = i = 0; i < chain->n_rules; i++) { if (keep_rule(chain->map[i], cmd, new_set, 0)) continue; if (start < 0) start = i; end = i; n++; } end++; /* first non-matching */ } else { /* Optimized search on rule numbers */ start = ipfw_find_rule(chain, num, 0); for (end = start; end < chain->n_rules; end++) { rule = chain->map[end]; if (num > 0 && rule->rulenum != num) break; if (!keep_rule(rule, cmd, new_set, num)) n++; } } if (n == 0) { /* A flush request (arg == 0 or cmd == 1) on empty * ruleset returns with no error. On the contrary, * if there is no match on a specific request, * we return EINVAL. */ if (arg != 0 && cmd != 1) error = EINVAL; break; } /* We have something to delete. Allocate the new map */ map = get_map(chain, -n, 1 /* locked */); if (map == NULL) { error = EINVAL; break; } /* 1. bcopy the initial part of the map */ if (start > 0) bcopy(chain->map, map, start * sizeof(struct ip_fw *)); /* 2. copy active rules between start and end */ for (i = ofs = start; i < end; i++) { rule = chain->map[i]; if (keep_rule(rule, cmd, new_set, num)) map[ofs++] = rule; } /* 3. copy the final part of the map */ bcopy(chain->map + end, map + ofs, (chain->n_rules - end) * sizeof(struct ip_fw *)); /* 4. swap the maps (under BH_LOCK) */ map = swap_map(chain, map, chain->n_rules - n); /* 5. now remove the rules deleted from the old map */ if (cmd == 1) ipfw_expire_dyn_rules(chain, NULL, new_set); for (i = start; i < end; i++) { rule = map[i]; if (keep_rule(rule, cmd, new_set, num)) continue; chain->static_len -= RULESIZE(rule); if (cmd != 1) ipfw_expire_dyn_rules(chain, rule, RESVD_SET); rule->x_next = chain->reap; chain->reap = rule; } break; /* * In the next 3 cases the loop stops at (n_rules - 1) * because the default rule is never eligible.. */ case 2: /* move rules with given RULE number to new set */ for (i = 0; i < chain->n_rules - 1; i++) { rule = chain->map[i]; if (rule->rulenum == num) rule->set = new_set; } break; case 3: /* move rules with given SET number to new set */ for (i = 0; i < chain->n_rules - 1; i++) { rule = chain->map[i]; if (rule->set == num) rule->set = new_set; } break; case 4: /* swap two sets */ for (i = 0; i < chain->n_rules - 1; i++) { rule = chain->map[i]; if (rule->set == num) rule->set = new_set; else if (rule->set == new_set) rule->set = num; } break; } rule = chain->reap; chain->reap = NULL; IPFW_UH_WUNLOCK(chain); ipfw_reap_rules(rule); if (map) free(map, M_IPFW); return error; } /* * Clear counters for a specific rule. * Normally run under IPFW_UH_RLOCK, but these are idempotent ops * so we only care that rules do not disappear. */ static void clear_counters(struct ip_fw *rule, int log_only) { ipfw_insn_log *l = (ipfw_insn_log *)ACTION_PTR(rule); if (log_only == 0) IPFW_ZERO_RULE_COUNTER(rule); if (l->o.opcode == O_LOG) l->log_left = l->max_log; } /** * Reset some or all counters on firewall rules. * The argument `arg' is an u_int32_t. The low 16 bit are the rule number, * the next 8 bits are the set number, the top 8 bits are the command: * 0 work with rules from all set's; * 1 work with rules only from specified set. * Specified rule number is zero if we want to clear all entries. * log_only is 1 if we only want to reset logs, zero otherwise. */ static int zero_entry(struct ip_fw_chain *chain, u_int32_t arg, int log_only) { struct ip_fw *rule; char *msg; int i; uint16_t rulenum = arg & 0xffff; uint8_t set = (arg >> 16) & 0xff; uint8_t cmd = (arg >> 24) & 0xff; if (cmd > 1) return (EINVAL); if (cmd == 1 && set > RESVD_SET) return (EINVAL); IPFW_UH_RLOCK(chain); if (rulenum == 0) { V_norule_counter = 0; for (i = 0; i < chain->n_rules; i++) { rule = chain->map[i]; /* Skip rules not in our set. */ if (cmd == 1 && rule->set != set) continue; clear_counters(rule, log_only); } msg = log_only ? "All logging counts reset" : "Accounting cleared"; } else { int cleared = 0; for (i = 0; i < chain->n_rules; i++) { rule = chain->map[i]; if (rule->rulenum == rulenum) { if (cmd == 0 || rule->set == set) clear_counters(rule, log_only); cleared = 1; } if (rule->rulenum > rulenum) break; } if (!cleared) { /* we did not find any matching rules */ IPFW_UH_RUNLOCK(chain); return (EINVAL); } msg = log_only ? "logging count reset" : "cleared"; } IPFW_UH_RUNLOCK(chain); if (V_fw_verbose) { int lev = LOG_SECURITY | LOG_NOTICE; if (rulenum) log(lev, "ipfw: Entry %d %s.\n", rulenum, msg); else log(lev, "ipfw: %s.\n", msg); } return (0); } /* * Check validity of the structure before insert. * Rules are simple, so this mostly need to check rule sizes. */ static int check_ipfw_struct(struct ip_fw *rule, int size) { int l, cmdlen = 0; int have_action=0; ipfw_insn *cmd; if (size < sizeof(*rule)) { printf("ipfw: rule too short\n"); return (EINVAL); } /* first, check for valid size */ l = RULESIZE(rule); if (l != size) { printf("ipfw: size mismatch (have %d want %d)\n", size, l); return (EINVAL); } if (rule->act_ofs >= rule->cmd_len) { printf("ipfw: bogus action offset (%u > %u)\n", rule->act_ofs, rule->cmd_len - 1); return (EINVAL); } /* * Now go for the individual checks. Very simple ones, basically only * instruction sizes. */ for (l = rule->cmd_len, cmd = rule->cmd ; l > 0 ; l -= cmdlen, cmd += cmdlen) { cmdlen = F_LEN(cmd); if (cmdlen > l) { printf("ipfw: opcode %d size truncated\n", cmd->opcode); return EINVAL; } switch (cmd->opcode) { case O_PROBE_STATE: case O_KEEP_STATE: case O_PROTO: case O_IP_SRC_ME: case O_IP_DST_ME: case O_LAYER2: case O_IN: case O_FRAG: case O_DIVERTED: case O_IPOPT: case O_IPTOS: case O_IPPRECEDENCE: case O_IPVER: case O_SOCKARG: case O_TCPFLAGS: case O_TCPOPTS: case O_ESTAB: case O_VERREVPATH: case O_VERSRCREACH: case O_ANTISPOOF: case O_IPSEC: #ifdef INET6 case O_IP6_SRC_ME: case O_IP6_DST_ME: case O_EXT_HDR: case O_IP6: #endif case O_IP4: case O_TAG: if (cmdlen != F_INSN_SIZE(ipfw_insn)) goto bad_size; break; case O_FIB: if (cmdlen != F_INSN_SIZE(ipfw_insn)) goto bad_size; if (cmd->arg1 >= rt_numfibs) { printf("ipfw: invalid fib number %d\n", cmd->arg1); return EINVAL; } break; case O_SETFIB: if (cmdlen != F_INSN_SIZE(ipfw_insn)) goto bad_size; if ((cmd->arg1 != IP_FW_TABLEARG) && (cmd->arg1 >= rt_numfibs)) { printf("ipfw: invalid fib number %d\n", cmd->arg1); return EINVAL; } goto check_action; case O_UID: case O_GID: case O_JAIL: case O_IP_SRC: case O_IP_DST: case O_TCPSEQ: case O_TCPACK: case O_PROB: case O_ICMPTYPE: if (cmdlen != F_INSN_SIZE(ipfw_insn_u32)) goto bad_size; break; case O_LIMIT: if (cmdlen != F_INSN_SIZE(ipfw_insn_limit)) goto bad_size; break; case O_LOG: if (cmdlen != F_INSN_SIZE(ipfw_insn_log)) goto bad_size; ((ipfw_insn_log *)cmd)->log_left = ((ipfw_insn_log *)cmd)->max_log; break; case O_IP_SRC_MASK: case O_IP_DST_MASK: /* only odd command lengths */ if ( !(cmdlen & 1) || cmdlen > 31) goto bad_size; break; case O_IP_SRC_SET: case O_IP_DST_SET: if (cmd->arg1 == 0 || cmd->arg1 > 256) { printf("ipfw: invalid set size %d\n", cmd->arg1); return EINVAL; } if (cmdlen != F_INSN_SIZE(ipfw_insn_u32) + (cmd->arg1+31)/32 ) goto bad_size; break; case O_IP_SRC_LOOKUP: case O_IP_DST_LOOKUP: if (cmd->arg1 >= V_fw_tables_max) { printf("ipfw: invalid table number %d\n", cmd->arg1); return (EINVAL); } if (cmdlen != F_INSN_SIZE(ipfw_insn) && cmdlen != F_INSN_SIZE(ipfw_insn_u32) + 1 && cmdlen != F_INSN_SIZE(ipfw_insn_u32)) goto bad_size; break; case O_MACADDR2: if (cmdlen != F_INSN_SIZE(ipfw_insn_mac)) goto bad_size; break; case O_NOP: case O_IPID: case O_IPTTL: case O_IPLEN: case O_TCPDATALEN: case O_TCPWIN: case O_TAGGED: if (cmdlen < 1 || cmdlen > 31) goto bad_size; break; case O_DSCP: if (cmdlen != F_INSN_SIZE(ipfw_insn_u32) + 1) goto bad_size; break; case O_MAC_TYPE: case O_IP_SRCPORT: case O_IP_DSTPORT: /* XXX artificial limit, 30 port pairs */ if (cmdlen < 2 || cmdlen > 31) goto bad_size; break; case O_RECV: case O_XMIT: case O_VIA: if (cmdlen != F_INSN_SIZE(ipfw_insn_if)) goto bad_size; break; case O_ALTQ: if (cmdlen != F_INSN_SIZE(ipfw_insn_altq)) goto bad_size; break; case O_PIPE: case O_QUEUE: if (cmdlen != F_INSN_SIZE(ipfw_insn)) goto bad_size; goto check_action; case O_FORWARD_IP: if (cmdlen != F_INSN_SIZE(ipfw_insn_sa)) goto bad_size; goto check_action; #ifdef INET6 case O_FORWARD_IP6: if (cmdlen != F_INSN_SIZE(ipfw_insn_sa6)) goto bad_size; goto check_action; #endif /* INET6 */ case O_DIVERT: case O_TEE: if (ip_divert_ptr == NULL) return EINVAL; else goto check_size; case O_NETGRAPH: case O_NGTEE: if (ng_ipfw_input_p == NULL) return EINVAL; else goto check_size; case O_NAT: if (!IPFW_NAT_LOADED) return EINVAL; if (cmdlen != F_INSN_SIZE(ipfw_insn_nat)) goto bad_size; goto check_action; case O_FORWARD_MAC: /* XXX not implemented yet */ case O_CHECK_STATE: case O_COUNT: case O_ACCEPT: case O_DENY: case O_REJECT: case O_SETDSCP: #ifdef INET6 case O_UNREACH6: #endif case O_SKIPTO: case O_REASS: case O_CALLRETURN: check_size: if (cmdlen != F_INSN_SIZE(ipfw_insn)) goto bad_size; check_action: if (have_action) { printf("ipfw: opcode %d, multiple actions" " not allowed\n", cmd->opcode); return EINVAL; } have_action = 1; if (l != cmdlen) { printf("ipfw: opcode %d, action must be" " last opcode\n", cmd->opcode); return EINVAL; } break; #ifdef INET6 case O_IP6_SRC: case O_IP6_DST: if (cmdlen != F_INSN_SIZE(struct in6_addr) + F_INSN_SIZE(ipfw_insn)) goto bad_size; break; case O_FLOW6ID: if (cmdlen != F_INSN_SIZE(ipfw_insn_u32) + ((ipfw_insn_u32 *)cmd)->o.arg1) goto bad_size; break; case O_IP6_SRC_MASK: case O_IP6_DST_MASK: if ( !(cmdlen & 1) || cmdlen > 127) goto bad_size; break; case O_ICMP6TYPE: if( cmdlen != F_INSN_SIZE( ipfw_insn_icmp6 ) ) goto bad_size; break; #endif default: switch (cmd->opcode) { #ifndef INET6 case O_IP6_SRC_ME: case O_IP6_DST_ME: case O_EXT_HDR: case O_IP6: case O_UNREACH6: case O_IP6_SRC: case O_IP6_DST: case O_FLOW6ID: case O_IP6_SRC_MASK: case O_IP6_DST_MASK: case O_ICMP6TYPE: printf("ipfw: no IPv6 support in kernel\n"); return EPROTONOSUPPORT; #endif default: printf("ipfw: opcode %d, unknown opcode\n", cmd->opcode); return EINVAL; } } } if (have_action == 0) { printf("ipfw: missing action\n"); return EINVAL; } return 0; bad_size: printf("ipfw: opcode %d size %d wrong\n", cmd->opcode, cmdlen); return EINVAL; } /* * Translation of requests for compatibility with FreeBSD 7.2/8. * a static variable tells us if we have an old client from userland, * and if necessary we translate requests and responses between the * two formats. */ static int is7 = 0; struct ip_fw7 { struct ip_fw7 *next; /* linked list of rules */ struct ip_fw7 *next_rule; /* ptr to next [skipto] rule */ /* 'next_rule' is used to pass up 'set_disable' status */ uint16_t act_ofs; /* offset of action in 32-bit units */ uint16_t cmd_len; /* # of 32-bit words in cmd */ uint16_t rulenum; /* rule number */ uint8_t set; /* rule set (0..31) */ // #define RESVD_SET 31 /* set for default and persistent rules */ uint8_t _pad; /* padding */ // uint32_t id; /* rule id, only in v.8 */ /* These fields are present in all rules. */ uint64_t pcnt; /* Packet counter */ uint64_t bcnt; /* Byte counter */ uint32_t timestamp; /* tv_sec of last match */ ipfw_insn cmd[1]; /* storage for commands */ }; int convert_rule_to_7(struct ip_fw *rule); int convert_rule_to_8(struct ip_fw *rule); #ifndef RULESIZE7 #define RULESIZE7(rule) (sizeof(struct ip_fw7) + \ ((struct ip_fw7 *)(rule))->cmd_len * 4 - 4) #endif /* * Copy the static and dynamic rules to the supplied buffer * and return the amount of space actually used. * Must be run under IPFW_UH_RLOCK */ static size_t ipfw_getrules(struct ip_fw_chain *chain, void *buf, size_t space) { char *bp = buf; char *ep = bp + space; struct ip_fw *rule, *dst; int l, i; time_t boot_seconds; boot_seconds = boottime.tv_sec; for (i = 0; i < chain->n_rules; i++) { rule = chain->map[i]; if (is7) { /* Convert rule to FreeBSd 7.2 format */ l = RULESIZE7(rule); if (bp + l + sizeof(uint32_t) <= ep) { int error; bcopy(rule, bp, l + sizeof(uint32_t)); error = convert_rule_to_7((struct ip_fw *) bp); if (error) return 0; /*XXX correct? */ /* * XXX HACK. Store the disable mask in the "next" * pointer in a wild attempt to keep the ABI the same. * Why do we do this on EVERY rule? */ bcopy(&V_set_disable, &(((struct ip_fw7 *)bp)->next_rule), sizeof(V_set_disable)); if (((struct ip_fw7 *)bp)->timestamp) ((struct ip_fw7 *)bp)->timestamp += boot_seconds; bp += l; } continue; /* go to next rule */ } /* normal mode, don't touch rules */ l = RULESIZE(rule); if (bp + l > ep) { /* should not happen */ printf("overflow dumping static rules\n"); break; } dst = (struct ip_fw *)bp; bcopy(rule, dst, l); /* * XXX HACK. Store the disable mask in the "next" * pointer in a wild attempt to keep the ABI the same. * Why do we do this on EVERY rule? */ bcopy(&V_set_disable, &dst->next_rule, sizeof(V_set_disable)); if (dst->timestamp) dst->timestamp += boot_seconds; bp += l; } ipfw_get_dynamic(chain, &bp, ep); /* protected by the dynamic lock */ return (bp - (char *)buf); } #define IP_FW3_OPLENGTH(x) ((x)->sopt_valsize - sizeof(ip_fw3_opheader)) /** * {set|get}sockopt parser. */ int ipfw_ctl(struct sockopt *sopt) { #define RULE_MAXSIZE (256*sizeof(u_int32_t)) int error; size_t size, len, valsize; struct ip_fw *buf, *rule; struct ip_fw_chain *chain; u_int32_t rulenum[2]; uint32_t opt; char xbuf[128]; ip_fw3_opheader *op3 = NULL; error = priv_check(sopt->sopt_td, PRIV_NETINET_IPFW); if (error) return (error); /* * Disallow modifications in really-really secure mode, but still allow * the logging counters to be reset. */ if (sopt->sopt_name == IP_FW_ADD || (sopt->sopt_dir == SOPT_SET && sopt->sopt_name != IP_FW_RESETLOG)) { error = securelevel_ge(sopt->sopt_td->td_ucred, 3); if (error) return (error); } chain = &V_layer3_chain; error = 0; /* Save original valsize before it is altered via sooptcopyin() */ valsize = sopt->sopt_valsize; if ((opt = sopt->sopt_name) == IP_FW3) { /* * Copy not less than sizeof(ip_fw3_opheader). * We hope any IP_FW3 command will fit into 128-byte buffer. */ if ((error = sooptcopyin(sopt, xbuf, sizeof(xbuf), sizeof(ip_fw3_opheader))) != 0) return (error); op3 = (ip_fw3_opheader *)xbuf; opt = op3->opcode; } switch (opt) { case IP_FW_GET: /* * pass up a copy of the current rules. Static rules * come first (the last of which has number IPFW_DEFAULT_RULE), * followed by a possibly empty list of dynamic rule. * The last dynamic rule has NULL in the "next" field. * * Note that the calculated size is used to bound the * amount of data returned to the user. The rule set may * change between calculating the size and returning the * data in which case we'll just return what fits. */ for (;;) { int len = 0, want; size = chain->static_len; size += ipfw_dyn_len(); if (size >= sopt->sopt_valsize) break; buf = malloc(size, M_TEMP, M_WAITOK); IPFW_UH_RLOCK(chain); /* check again how much space we need */ want = chain->static_len + ipfw_dyn_len(); if (size >= want) len = ipfw_getrules(chain, buf, size); IPFW_UH_RUNLOCK(chain); if (size >= want) error = sooptcopyout(sopt, buf, len); free(buf, M_TEMP); if (size >= want) break; } break; case IP_FW_FLUSH: /* locking is done within del_entry() */ error = del_entry(chain, 0); /* special case, rule=0, cmd=0 means all */ break; case IP_FW_ADD: rule = malloc(RULE_MAXSIZE, M_TEMP, M_WAITOK); error = sooptcopyin(sopt, rule, RULE_MAXSIZE, sizeof(struct ip_fw7) ); /* * If the size of commands equals RULESIZE7 then we assume * a FreeBSD7.2 binary is talking to us (set is7=1). * is7 is persistent so the next 'ipfw list' command * will use this format. * NOTE: If wrong version is guessed (this can happen if * the first ipfw command is 'ipfw [pipe] list') * the ipfw binary may crash or loop infinitly... */ if (sopt->sopt_valsize == RULESIZE7(rule)) { is7 = 1; error = convert_rule_to_8(rule); if (error) return error; if (error == 0) error = check_ipfw_struct(rule, RULESIZE(rule)); } else { is7 = 0; if (error == 0) error = check_ipfw_struct(rule, sopt->sopt_valsize); } if (error == 0) { /* locking is done within ipfw_add_rule() */ error = ipfw_add_rule(chain, rule); size = RULESIZE(rule); if (!error && sopt->sopt_dir == SOPT_GET) { if (is7) { error = convert_rule_to_7(rule); size = RULESIZE7(rule); if (error) return error; } error = sooptcopyout(sopt, rule, size); } } free(rule, M_TEMP); break; case IP_FW_DEL: /* * IP_FW_DEL is used for deleting single rules or sets, * and (ab)used to atomically manipulate sets. Argument size * is used to distinguish between the two: * sizeof(u_int32_t) * delete single rule or set of rules, * or reassign rules (or sets) to a different set. * 2*sizeof(u_int32_t) * atomic disable/enable sets. * first u_int32_t contains sets to be disabled, * second u_int32_t contains sets to be enabled. */ error = sooptcopyin(sopt, rulenum, 2*sizeof(u_int32_t), sizeof(u_int32_t)); if (error) break; size = sopt->sopt_valsize; if (size == sizeof(u_int32_t) && rulenum[0] != 0) { /* delete or reassign, locking done in del_entry() */ error = del_entry(chain, rulenum[0]); } else if (size == 2*sizeof(u_int32_t)) { /* set enable/disable */ IPFW_UH_WLOCK(chain); V_set_disable = (V_set_disable | rulenum[0]) & ~rulenum[1] & ~(1<sopt_val != 0) { error = sooptcopyin(sopt, rulenum, sizeof(u_int32_t), sizeof(u_int32_t)); if (error) break; } error = zero_entry(chain, rulenum[0], sopt->sopt_name == IP_FW_RESETLOG); break; /*--- TABLE manipulations are protected by the IPFW_LOCK ---*/ case IP_FW_TABLE_ADD: { ipfw_table_entry ent; error = sooptcopyin(sopt, &ent, sizeof(ent), sizeof(ent)); if (error) break; error = ipfw_add_table_entry(chain, ent.tbl, &ent.addr, sizeof(ent.addr), ent.masklen, IPFW_TABLE_CIDR, ent.value); } break; case IP_FW_TABLE_DEL: { ipfw_table_entry ent; error = sooptcopyin(sopt, &ent, sizeof(ent), sizeof(ent)); if (error) break; error = ipfw_del_table_entry(chain, ent.tbl, &ent.addr, sizeof(ent.addr), ent.masklen, IPFW_TABLE_CIDR); } break; case IP_FW_TABLE_XADD: /* IP_FW3 */ case IP_FW_TABLE_XDEL: /* IP_FW3 */ { ipfw_table_xentry *xent = (ipfw_table_xentry *)(op3 + 1); /* Check minimum header size */ if (IP_FW3_OPLENGTH(sopt) < offsetof(ipfw_table_xentry, k)) { error = EINVAL; break; } /* Check if len field is valid */ if (xent->len > sizeof(ipfw_table_xentry)) { error = EINVAL; break; } len = xent->len - offsetof(ipfw_table_xentry, k); error = (opt == IP_FW_TABLE_XADD) ? ipfw_add_table_entry(chain, xent->tbl, &xent->k, len, xent->masklen, xent->type, xent->value) : ipfw_del_table_entry(chain, xent->tbl, &xent->k, len, xent->masklen, xent->type); } break; case IP_FW_TABLE_FLUSH: { u_int16_t tbl; error = sooptcopyin(sopt, &tbl, sizeof(tbl), sizeof(tbl)); if (error) break; error = ipfw_flush_table(chain, tbl); } break; case IP_FW_TABLE_GETSIZE: { u_int32_t tbl, cnt; if ((error = sooptcopyin(sopt, &tbl, sizeof(tbl), sizeof(tbl)))) break; IPFW_RLOCK(chain); error = ipfw_count_table(chain, tbl, &cnt); IPFW_RUNLOCK(chain); if (error) break; error = sooptcopyout(sopt, &cnt, sizeof(cnt)); } break; case IP_FW_TABLE_LIST: { ipfw_table *tbl; if (sopt->sopt_valsize < sizeof(*tbl)) { error = EINVAL; break; } size = sopt->sopt_valsize; tbl = malloc(size, M_TEMP, M_WAITOK); error = sooptcopyin(sopt, tbl, size, sizeof(*tbl)); if (error) { free(tbl, M_TEMP); break; } tbl->size = (size - sizeof(*tbl)) / sizeof(ipfw_table_entry); IPFW_RLOCK(chain); error = ipfw_dump_table(chain, tbl); IPFW_RUNLOCK(chain); if (error) { free(tbl, M_TEMP); break; } error = sooptcopyout(sopt, tbl, size); free(tbl, M_TEMP); } break; case IP_FW_TABLE_XGETSIZE: /* IP_FW3 */ { uint32_t *tbl; if (IP_FW3_OPLENGTH(sopt) < sizeof(uint32_t)) { error = EINVAL; break; } tbl = (uint32_t *)(op3 + 1); IPFW_RLOCK(chain); error = ipfw_count_xtable(chain, *tbl, tbl); IPFW_RUNLOCK(chain); if (error) break; error = sooptcopyout(sopt, op3, sopt->sopt_valsize); } break; case IP_FW_TABLE_XLIST: /* IP_FW3 */ { ipfw_xtable *tbl; if ((size = valsize) < sizeof(ipfw_xtable)) { error = EINVAL; break; } tbl = malloc(size, M_TEMP, M_ZERO | M_WAITOK); memcpy(tbl, op3, sizeof(ipfw_xtable)); /* Get maximum number of entries we can store */ tbl->size = (size - sizeof(ipfw_xtable)) / sizeof(ipfw_table_xentry); IPFW_RLOCK(chain); error = ipfw_dump_xtable(chain, tbl); IPFW_RUNLOCK(chain); if (error) { free(tbl, M_TEMP); break; } /* Revert size field back to bytes */ tbl->size = tbl->size * sizeof(ipfw_table_xentry) + sizeof(ipfw_table); /* * Since we call sooptcopyin() with small buffer, sopt_valsize is * decreased to reflect supplied buffer size. Set it back to original value */ sopt->sopt_valsize = valsize; error = sooptcopyout(sopt, tbl, size); free(tbl, M_TEMP); } break; /*--- NAT operations are protected by the IPFW_LOCK ---*/ case IP_FW_NAT_CFG: if (IPFW_NAT_LOADED) error = ipfw_nat_cfg_ptr(sopt); else { printf("IP_FW_NAT_CFG: %s\n", "ipfw_nat not present, please load it"); error = EINVAL; } break; case IP_FW_NAT_DEL: if (IPFW_NAT_LOADED) error = ipfw_nat_del_ptr(sopt); else { printf("IP_FW_NAT_DEL: %s\n", "ipfw_nat not present, please load it"); error = EINVAL; } break; case IP_FW_NAT_GET_CONFIG: if (IPFW_NAT_LOADED) error = ipfw_nat_get_cfg_ptr(sopt); else { printf("IP_FW_NAT_GET_CFG: %s\n", "ipfw_nat not present, please load it"); error = EINVAL; } break; case IP_FW_NAT_GET_LOG: if (IPFW_NAT_LOADED) error = ipfw_nat_get_log_ptr(sopt); else { printf("IP_FW_NAT_GET_LOG: %s\n", "ipfw_nat not present, please load it"); error = EINVAL; } break; default: printf("ipfw: ipfw_ctl invalid option %d\n", sopt->sopt_name); error = EINVAL; } return (error); #undef RULE_MAXSIZE } #define RULE_MAXSIZE (256*sizeof(u_int32_t)) /* Functions to convert rules 7.2 <==> 8.0 */ int convert_rule_to_7(struct ip_fw *rule) { /* Used to modify original rule */ struct ip_fw7 *rule7 = (struct ip_fw7 *)rule; /* copy of original rule, version 8 */ struct ip_fw *tmp; /* Used to copy commands */ ipfw_insn *ccmd, *dst; int ll = 0, ccmdlen = 0; tmp = malloc(RULE_MAXSIZE, M_TEMP, M_NOWAIT | M_ZERO); if (tmp == NULL) { return 1; //XXX error } bcopy(rule, tmp, RULE_MAXSIZE); /* Copy fields */ rule7->_pad = tmp->_pad; rule7->set = tmp->set; rule7->rulenum = tmp->rulenum; rule7->cmd_len = tmp->cmd_len; rule7->act_ofs = tmp->act_ofs; rule7->next_rule = (struct ip_fw7 *)tmp->next_rule; rule7->next = (struct ip_fw7 *)tmp->x_next; rule7->cmd_len = tmp->cmd_len; rule7->pcnt = tmp->pcnt; rule7->bcnt = tmp->bcnt; rule7->timestamp = tmp->timestamp; /* Copy commands */ for (ll = tmp->cmd_len, ccmd = tmp->cmd, dst = rule7->cmd ; ll > 0 ; ll -= ccmdlen, ccmd += ccmdlen, dst += ccmdlen) { ccmdlen = F_LEN(ccmd); bcopy(ccmd, dst, F_LEN(ccmd)*sizeof(uint32_t)); if (dst->opcode > O_NAT) /* O_REASS doesn't exists in 7.2 version, so * decrement opcode if it is after O_REASS */ dst->opcode--; if (ccmdlen > ll) { printf("ipfw: opcode %d size truncated\n", ccmd->opcode); return EINVAL; } } free(tmp, M_TEMP); return 0; } int convert_rule_to_8(struct ip_fw *rule) { /* Used to modify original rule */ struct ip_fw7 *rule7 = (struct ip_fw7 *) rule; /* Used to copy commands */ ipfw_insn *ccmd, *dst; int ll = 0, ccmdlen = 0; /* Copy of original rule */ struct ip_fw7 *tmp = malloc(RULE_MAXSIZE, M_TEMP, M_NOWAIT | M_ZERO); if (tmp == NULL) { return 1; //XXX error } bcopy(rule7, tmp, RULE_MAXSIZE); for (ll = tmp->cmd_len, ccmd = tmp->cmd, dst = rule->cmd ; ll > 0 ; ll -= ccmdlen, ccmd += ccmdlen, dst += ccmdlen) { ccmdlen = F_LEN(ccmd); bcopy(ccmd, dst, F_LEN(ccmd)*sizeof(uint32_t)); if (dst->opcode > O_NAT) /* O_REASS doesn't exists in 7.2 version, so * increment opcode if it is after O_REASS */ dst->opcode++; if (ccmdlen > ll) { printf("ipfw: opcode %d size truncated\n", ccmd->opcode); return EINVAL; } } rule->_pad = tmp->_pad; rule->set = tmp->set; rule->rulenum = tmp->rulenum; rule->cmd_len = tmp->cmd_len; rule->act_ofs = tmp->act_ofs; rule->next_rule = (struct ip_fw *)tmp->next_rule; rule->x_next = (struct ip_fw *)tmp->next; rule->cmd_len = tmp->cmd_len; rule->id = 0; /* XXX see if is ok = 0 */ rule->pcnt = tmp->pcnt; rule->bcnt = tmp->bcnt; rule->timestamp = tmp->timestamp; free (tmp, M_TEMP); return 0; } /* end of file */