diff options
Diffstat (limited to 'net/ipv4/cipso_ipv4.c')
| -rw-r--r-- | net/ipv4/cipso_ipv4.c | 186 |
1 files changed, 109 insertions, 77 deletions
diff --git a/net/ipv4/cipso_ipv4.c b/net/ipv4/cipso_ipv4.c index 777fa3b7fb13..709021197e1c 100644 --- a/net/ipv4/cipso_ipv4.c +++ b/net/ipv4/cipso_ipv4.c @@ -1,3 +1,4 @@ +// SPDX-License-Identifier: GPL-2.0-or-later /* * CIPSO - Commercial IP Security Option * @@ -9,30 +10,15 @@ * * The CIPSO draft specification can be found in the kernel's Documentation * directory as well as the following URL: - * http://tools.ietf.org/id/draft-ietf-cipso-ipsecurity-01.txt + * https://tools.ietf.org/id/draft-ietf-cipso-ipsecurity-01.txt * The FIPS-188 specification can be found at the following URL: - * http://www.itl.nist.gov/fipspubs/fip188.htm + * https://www.itl.nist.gov/fipspubs/fip188.htm * * Author: Paul Moore <paul.moore@hp.com> - * */ /* * (c) Copyright Hewlett-Packard Development Company, L.P., 2006, 2008 - * - * This program is free software; you can redistribute it and/or modify - * it under the terms of the GNU General Public License as published by - * the Free Software Foundation; either version 2 of the License, or - * (at your option) any later version. - * - * This program is distributed in the hope that it will be useful, - * but WITHOUT ANY WARRANTY; without even the implied warranty of - * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See - * the GNU General Public License for more details. - * - * You should have received a copy of the GNU General Public License - * along with this program; if not, see <http://www.gnu.org/licenses/>. - * */ #include <linux/init.h> @@ -51,7 +37,7 @@ #include <net/cipso_ipv4.h> #include <linux/atomic.h> #include <linux/bug.h> -#include <asm/unaligned.h> +#include <linux/unaligned.h> /* List of available DOI definitions */ /* XXX - This currently assumes a minimal number of different DOIs in use, @@ -87,7 +73,7 @@ struct cipso_v4_map_cache_entry { static struct cipso_v4_map_cache_bkt *cipso_v4_cache; /* Restricted bitmap (tag #1) flags */ -int cipso_v4_rbm_optfmt = 0; +int cipso_v4_rbm_optfmt; int cipso_v4_rbm_strictvalid = 1; /* @@ -201,8 +187,7 @@ static int __init cipso_v4_cache_init(void) * cipso_v4_cache_invalidate - Invalidates the current CIPSO cache * * Description: - * Invalidates and frees any entries in the CIPSO cache. Returns zero on - * success and negative values on failure. + * Invalidates and frees any entries in the CIPSO cache. * */ void cipso_v4_cache_invalidate(void) @@ -254,7 +239,7 @@ static int cipso_v4_cache_check(const unsigned char *key, struct cipso_v4_map_cache_entry *prev_entry = NULL; u32 hash; - if (!cipso_v4_cache_enabled) + if (!READ_ONCE(cipso_v4_cache_enabled)) return -ENOENT; hash = cipso_v4_map_cache_hash(key, key_len); @@ -297,7 +282,7 @@ static int cipso_v4_cache_check(const unsigned char *key, /** * cipso_v4_cache_add - Add an entry to the CIPSO cache - * @skb: the packet + * @cipso_ptr: pointer to CIPSO IP option * @secattr: the packet's security attributes * * Description: @@ -311,13 +296,14 @@ static int cipso_v4_cache_check(const unsigned char *key, int cipso_v4_cache_add(const unsigned char *cipso_ptr, const struct netlbl_lsm_secattr *secattr) { + int bkt_size = READ_ONCE(cipso_v4_cache_bucketsize); int ret_val = -EPERM; u32 bkt; struct cipso_v4_map_cache_entry *entry = NULL; struct cipso_v4_map_cache_entry *old_entry = NULL; u32 cipso_ptr_len; - if (!cipso_v4_cache_enabled || cipso_v4_cache_bucketsize <= 0) + if (!READ_ONCE(cipso_v4_cache_enabled) || bkt_size <= 0) return 0; cipso_ptr_len = cipso_ptr[1]; @@ -337,7 +323,7 @@ int cipso_v4_cache_add(const unsigned char *cipso_ptr, bkt = entry->hash & (CIPSO_V4_CACHE_BUCKETS - 1); spin_lock_bh(&cipso_v4_cache[bkt].lock); - if (cipso_v4_cache[bkt].size < cipso_v4_cache_bucketsize) { + if (cipso_v4_cache[bkt].size < bkt_size) { list_add(&entry->list, &cipso_v4_cache[bkt].list); cipso_v4_cache[bkt].size += 1; } else { @@ -486,6 +472,7 @@ void cipso_v4_doi_free(struct cipso_v4_doi *doi_def) kfree(doi_def->map.std->lvl.local); kfree(doi_def->map.std->cat.cipso); kfree(doi_def->map.std->cat.local); + kfree(doi_def->map.std); break; } kfree(doi_def); @@ -512,7 +499,7 @@ static void cipso_v4_doi_free_rcu(struct rcu_head *entry) /** * cipso_v4_doi_remove - Remove an existing DOI from the CIPSO protocol engine * @doi: the DOI value - * @audit_secid: the LSM secid to use in the audit message + * @audit_info: NetLabel audit information * * Description: * Removes a DOI definition from the CIPSO engine. The NetLabel routines will @@ -533,16 +520,10 @@ int cipso_v4_doi_remove(u32 doi, struct netlbl_audit *audit_info) ret_val = -ENOENT; goto doi_remove_return; } - if (!refcount_dec_and_test(&doi_def->refcount)) { - spin_unlock(&cipso_v4_doi_list_lock); - ret_val = -EBUSY; - goto doi_remove_return; - } list_del_rcu(&doi_def->list); spin_unlock(&cipso_v4_doi_list_lock); - cipso_v4_cache_invalidate(); - call_rcu(&doi_def->rcu, cipso_v4_doi_free_rcu); + cipso_v4_doi_putdef(doi_def); ret_val = 0; doi_remove_return: @@ -599,9 +580,6 @@ void cipso_v4_doi_putdef(struct cipso_v4_doi *doi_def) if (!refcount_dec_and_test(&doi_def->refcount)) return; - spin_lock(&cipso_v4_doi_list_lock); - list_del_rcu(&doi_def->list); - spin_unlock(&cipso_v4_doi_list_lock); cipso_v4_cache_invalidate(); call_rcu(&doi_def->rcu, cipso_v4_doi_free_rcu); @@ -667,7 +645,8 @@ static int cipso_v4_map_lvl_valid(const struct cipso_v4_doi *doi_def, u8 level) case CIPSO_V4_MAP_PASS: return 0; case CIPSO_V4_MAP_TRANS: - if (doi_def->map.std->lvl.cipso[level] < CIPSO_V4_INV_LVL) + if ((level < doi_def->map.std->lvl.cipso_size) && + (doi_def->map.std->lvl.cipso[level] < CIPSO_V4_INV_LVL)) return 0; break; } @@ -885,11 +864,8 @@ static int cipso_v4_map_cat_rbm_ntoh(const struct cipso_v4_doi *doi_def, net_clen_bits, net_spot + 1, 1); - if (net_spot < 0) { - if (net_spot == -2) - return -EFAULT; + if (net_spot < 0) return 0; - } switch (doi_def->type) { case CIPSO_V4_MAP_PASS: @@ -1175,7 +1151,7 @@ static void cipso_v4_gentag_hdr(const struct cipso_v4_doi *doi_def, { buf[0] = IPOPT_CIPSO; buf[1] = CIPSO_V4_HDR_LEN + len; - *(__be32 *)&buf[2] = htonl(doi_def->doi); + put_unaligned_be32(doi_def->doi, &buf[2]); } /** @@ -1221,7 +1197,8 @@ static int cipso_v4_gentag_rbm(const struct cipso_v4_doi *doi_def, /* This will send packets using the "optimized" format when * possible as specified in section 3.4.2.6 of the * CIPSO draft. */ - if (cipso_v4_rbm_optfmt && ret_val > 0 && ret_val <= 10) + if (READ_ONCE(cipso_v4_rbm_optfmt) && ret_val > 0 && + ret_val <= 10) tag_len = 14; else tag_len = 4 + ret_val; @@ -1271,7 +1248,8 @@ static int cipso_v4_parsetag_rbm(const struct cipso_v4_doi *doi_def, return ret_val; } - secattr->flags |= NETLBL_SECATTR_MLS_CAT; + if (secattr->attr.mls.cat) + secattr->flags |= NETLBL_SECATTR_MLS_CAT; } return 0; @@ -1452,7 +1430,8 @@ static int cipso_v4_parsetag_rng(const struct cipso_v4_doi *doi_def, return ret_val; } - secattr->flags |= NETLBL_SECATTR_MLS_CAT; + if (secattr->attr.mls.cat) + secattr->flags |= NETLBL_SECATTR_MLS_CAT; } return 0; @@ -1546,6 +1525,7 @@ unsigned char *cipso_v4_optptr(const struct sk_buff *skb) /** * cipso_v4_validate - Validate a CIPSO option + * @skb: the packet * @option: the start of the option, on error it is set to point to the error * * Description: @@ -1622,7 +1602,7 @@ int cipso_v4_validate(const struct sk_buff *skb, unsigned char **option) * all the CIPSO validations here but it doesn't * really specify _exactly_ what we need to validate * ... so, just make it a sysctl tunable. */ - if (cipso_v4_rbm_strictvalid) { + if (READ_ONCE(cipso_v4_rbm_strictvalid)) { if (cipso_v4_map_lvl_valid(doi_def, tag[3]) < 0) { err_offset = opt_iter + 3; @@ -1735,13 +1715,30 @@ validate_return: */ void cipso_v4_error(struct sk_buff *skb, int error, u32 gateway) { + struct inet_skb_parm parm; + int res; + if (ip_hdr(skb)->protocol == IPPROTO_ICMP || error != -EACCES) return; + /* + * We might be called above the IP layer, + * so we can not use icmp_send and IPCB here. + */ + + memset(&parm, 0, sizeof(parm)); + parm.opt.optlen = ip_hdr(skb)->ihl * 4 - sizeof(struct iphdr); + rcu_read_lock(); + res = __ip_options_compile(dev_net(skb->dev), &parm.opt, skb, NULL); + rcu_read_unlock(); + + if (res) + return; + if (gateway) - icmp_send(skb, ICMP_DEST_UNREACH, ICMP_NET_ANO, 0); + __icmp_send(skb, ICMP_DEST_UNREACH, ICMP_NET_ANO, 0, &parm); else - icmp_send(skb, ICMP_DEST_UNREACH, ICMP_HOST_ANO, 0); + __icmp_send(skb, ICMP_DEST_UNREACH, ICMP_HOST_ANO, 0, &parm); } /** @@ -1812,11 +1809,35 @@ static int cipso_v4_genopt(unsigned char *buf, u32 buf_len, return CIPSO_V4_HDR_LEN + ret_val; } +static int cipso_v4_get_actual_opt_len(const unsigned char *data, int len) +{ + int iter = 0, optlen = 0; + + /* determining the new total option length is tricky because of + * the padding necessary, the only thing i can think to do at + * this point is walk the options one-by-one, skipping the + * padding at the end to determine the actual option size and + * from there we can determine the new total option length + */ + while (iter < len) { + if (data[iter] == IPOPT_END) { + break; + } else if (data[iter] == IPOPT_NOP) { + iter++; + } else { + iter += data[iter + 1]; + optlen = iter; + } + } + return optlen; +} + /** * cipso_v4_sock_setattr - Add a CIPSO option to a socket * @sk: the socket * @doi_def: the CIPSO DOI to use * @secattr: the specific security attributes of the socket + * @sk_locked: true if caller holds the socket lock * * Description: * Set the CIPSO option on the given socket using the DOI definition and @@ -1828,7 +1849,8 @@ static int cipso_v4_genopt(unsigned char *buf, u32 buf_len, */ int cipso_v4_sock_setattr(struct sock *sk, const struct cipso_v4_doi *doi_def, - const struct netlbl_lsm_secattr *secattr) + const struct netlbl_lsm_secattr *secattr, + bool sk_locked) { int ret_val = -EPERM; unsigned char *buf = NULL; @@ -1878,9 +1900,8 @@ int cipso_v4_sock_setattr(struct sock *sk, sk_inet = inet_sk(sk); - old = rcu_dereference_protected(sk_inet->inet_opt, - lockdep_sock_is_held(sk)); - if (sk_inet->is_icsk) { + old = rcu_dereference_protected(sk_inet->inet_opt, sk_locked); + if (inet_test_bit(IS_ICSK, sk)) { sk_conn = inet_csk(sk); if (old) sk_conn->icsk_ext_hdr_len -= old->opt.optlen; @@ -1954,7 +1975,7 @@ int cipso_v4_req_setattr(struct request_sock *req, buf = NULL; req_inet = inet_rsk(req); - opt = xchg((__force struct ip_options_rcu **)&req_inet->ireq_opt, opt); + opt = unrcu_pointer(xchg(&req_inet->ireq_opt, RCU_INITIALIZER(opt))); if (opt) kfree_rcu(opt, rcu); @@ -1987,7 +2008,6 @@ static int cipso_v4_delopt(struct ip_options_rcu __rcu **opt_ptr) u8 cipso_len; u8 cipso_off; unsigned char *cipso_ptr; - int iter; int optlen_new; cipso_off = opt->opt.cipso - sizeof(struct iphdr); @@ -2007,19 +2027,8 @@ static int cipso_v4_delopt(struct ip_options_rcu __rcu **opt_ptr) memmove(cipso_ptr, cipso_ptr + cipso_len, opt->opt.optlen - cipso_off - cipso_len); - /* determining the new total option length is tricky because of - * the padding necessary, the only thing i can think to do at - * this point is walk the options one-by-one, skipping the - * padding at the end to determine the actual option size and - * from there we can determine the new total option length */ - iter = 0; - optlen_new = 0; - while (iter < opt->opt.optlen) - if (opt->opt.__data[iter] != IPOPT_NOP) { - iter += opt->opt.__data[iter + 1]; - optlen_new = iter; - } else - iter++; + optlen_new = cipso_v4_get_actual_opt_len(opt->opt.__data, + opt->opt.optlen); hdr_delta = opt->opt.optlen; opt->opt.optlen = (optlen_new + 3) & ~3; hdr_delta -= opt->opt.optlen; @@ -2050,7 +2059,7 @@ void cipso_v4_sock_delattr(struct sock *sk) sk_inet = inet_sk(sk); hdr_delta = cipso_v4_delopt(&sk_inet->inet_opt); - if (sk_inet->is_icsk && hdr_delta > 0) { + if (inet_test_bit(IS_ICSK, sk) && hdr_delta > 0) { struct inet_connection_sock *sk_conn = inet_csk(sk); sk_conn->icsk_ext_hdr_len -= hdr_delta; sk_conn->icsk_sync_mss(sk, sk_conn->icsk_pmtu_cookie); @@ -2059,7 +2068,7 @@ void cipso_v4_sock_delattr(struct sock *sk) /** * cipso_v4_req_delattr - Delete the CIPSO option from a request socket - * @reg: the request socket + * @req: the request socket * * Description: * Removes the CIPSO option from a request socket, if present. @@ -2151,6 +2160,7 @@ int cipso_v4_sock_getattr(struct sock *sk, struct netlbl_lsm_secattr *secattr) /** * cipso_v4_skbuff_setattr - Set the CIPSO option on a packet * @skb: the packet + * @doi_def: the DOI structure * @secattr: the security attributes * * Description: @@ -2220,7 +2230,7 @@ int cipso_v4_skbuff_setattr(struct sk_buff *skb, memset((char *)(iph + 1) + buf_len, 0, opt_len - buf_len); if (len_delta != 0) { iph->ihl = 5 + (opt_len >> 2); - iph->tot_len = htons(skb->len); + iph_set_totlen(iph, skb->len); } ip_send_check(iph); @@ -2238,7 +2248,8 @@ int cipso_v4_skbuff_setattr(struct sk_buff *skb, */ int cipso_v4_skbuff_delattr(struct sk_buff *skb) { - int ret_val; + int ret_val, cipso_len, hdr_len_actual, new_hdr_len_actual, new_hdr_len, + hdr_len_delta; struct iphdr *iph; struct ip_options *opt = &IPCB(skb)->opt; unsigned char *cipso_ptr; @@ -2251,16 +2262,37 @@ int cipso_v4_skbuff_delattr(struct sk_buff *skb) if (ret_val < 0) return ret_val; - /* the easiest thing to do is just replace the cipso option with noop - * options since we don't change the size of the packet, although we - * still need to recalculate the checksum */ - iph = ip_hdr(skb); cipso_ptr = (unsigned char *)iph + opt->cipso; - memset(cipso_ptr, IPOPT_NOOP, cipso_ptr[1]); + cipso_len = cipso_ptr[1]; + + hdr_len_actual = sizeof(struct iphdr) + + cipso_v4_get_actual_opt_len((unsigned char *)(iph + 1), + opt->optlen); + new_hdr_len_actual = hdr_len_actual - cipso_len; + new_hdr_len = (new_hdr_len_actual + 3) & ~3; + hdr_len_delta = (iph->ihl << 2) - new_hdr_len; + + /* 1. shift any options after CIPSO to the left */ + memmove(cipso_ptr, cipso_ptr + cipso_len, + new_hdr_len_actual - opt->cipso); + /* 2. move the whole IP header to its new place */ + memmove((unsigned char *)iph + hdr_len_delta, iph, new_hdr_len_actual); + /* 3. adjust the skb layout */ + skb_pull(skb, hdr_len_delta); + skb_reset_network_header(skb); + iph = ip_hdr(skb); + /* 4. re-fill new padding with IPOPT_END (may now be longer) */ + memset((unsigned char *)iph + new_hdr_len_actual, IPOPT_END, + new_hdr_len - new_hdr_len_actual); + + opt->optlen -= hdr_len_delta; opt->cipso = 0; opt->is_changed = 1; - + if (hdr_len_delta != 0) { + iph->ihl = new_hdr_len >> 2; + iph_set_totlen(iph, skb->len); + } ip_send_check(iph); return 0; |
