Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1 | /* |
| 2 | * Copyright (C)2002 USAGI/WIDE Project |
YOSHIFUJI Hideaki | 1ab1457 | 2007-02-09 23:24:49 +0900 | [diff] [blame] | 3 | * |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 4 | * This program is free software; you can redistribute it and/or modify |
| 5 | * it under the terms of the GNU General Public License as published by |
| 6 | * the Free Software Foundation; either version 2 of the License, or |
| 7 | * (at your option) any later version. |
YOSHIFUJI Hideaki | 1ab1457 | 2007-02-09 23:24:49 +0900 | [diff] [blame] | 8 | * |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 9 | * This program is distributed in the hope that it will be useful, |
| 10 | * but WITHOUT ANY WARRANTY; without even the implied warranty of |
| 11 | * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the |
| 12 | * GNU General Public License for more details. |
YOSHIFUJI Hideaki | 1ab1457 | 2007-02-09 23:24:49 +0900 | [diff] [blame] | 13 | * |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 14 | * You should have received a copy of the GNU General Public License |
| 15 | * along with this program; if not, write to the Free Software |
| 16 | * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA |
| 17 | * |
| 18 | * Authors |
| 19 | * |
YOSHIFUJI Hideaki | 1ab1457 | 2007-02-09 23:24:49 +0900 | [diff] [blame] | 20 | * Mitsuru KANDA @USAGI : IPv6 Support |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 21 | * Kazunori MIYAZAWA @USAGI : |
| 22 | * Kunihiro Ishiguro <kunihiro@ipinfusion.com> |
YOSHIFUJI Hideaki | 1ab1457 | 2007-02-09 23:24:49 +0900 | [diff] [blame] | 23 | * |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 24 | * This file is derived from net/ipv4/ah.c. |
| 25 | */ |
| 26 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 27 | #include <linux/module.h> |
| 28 | #include <net/ip.h> |
| 29 | #include <net/ah.h> |
| 30 | #include <linux/crypto.h> |
| 31 | #include <linux/pfkeyv2.h> |
Herbert Xu | b7c6538 | 2007-10-09 13:33:35 -0700 | [diff] [blame] | 32 | #include <linux/spinlock.h> |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 33 | #include <linux/string.h> |
| 34 | #include <net/icmp.h> |
| 35 | #include <net/ipv6.h> |
Arnaldo Carvalho de Melo | 14c8502 | 2005-12-27 02:43:12 -0200 | [diff] [blame] | 36 | #include <net/protocol.h> |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 37 | #include <net/xfrm.h> |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 38 | |
| 39 | static int zero_out_mutable_opts(struct ipv6_opt_hdr *opthdr) |
| 40 | { |
| 41 | u8 *opt = (u8 *)opthdr; |
| 42 | int len = ipv6_optlen(opthdr); |
| 43 | int off = 0; |
| 44 | int optlen = 0; |
| 45 | |
| 46 | off += 2; |
| 47 | len -= 2; |
| 48 | |
| 49 | while (len > 0) { |
| 50 | |
| 51 | switch (opt[off]) { |
| 52 | |
| 53 | case IPV6_TLV_PAD0: |
| 54 | optlen = 1; |
| 55 | break; |
| 56 | default: |
YOSHIFUJI Hideaki | 1ab1457 | 2007-02-09 23:24:49 +0900 | [diff] [blame] | 57 | if (len < 2) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 58 | goto bad; |
| 59 | optlen = opt[off+1]+2; |
| 60 | if (len < optlen) |
| 61 | goto bad; |
| 62 | if (opt[off] & 0x20) |
| 63 | memset(&opt[off+2], 0, opt[off+1]); |
| 64 | break; |
| 65 | } |
| 66 | |
| 67 | off += optlen; |
| 68 | len -= optlen; |
| 69 | } |
| 70 | if (len == 0) |
| 71 | return 1; |
| 72 | |
| 73 | bad: |
| 74 | return 0; |
| 75 | } |
| 76 | |
Masahide NAKAMURA | 59fbb3a6 | 2007-06-26 23:56:32 -0700 | [diff] [blame] | 77 | #if defined(CONFIG_IPV6_MIP6) || defined(CONFIG_IPV6_MIP6_MODULE) |
Masahide NAKAMURA | 27637df | 2006-08-23 19:29:47 -0700 | [diff] [blame] | 78 | /** |
| 79 | * ipv6_rearrange_destopt - rearrange IPv6 destination options header |
| 80 | * @iph: IPv6 header |
| 81 | * @destopt: destionation options header |
| 82 | */ |
| 83 | static void ipv6_rearrange_destopt(struct ipv6hdr *iph, struct ipv6_opt_hdr *destopt) |
| 84 | { |
| 85 | u8 *opt = (u8 *)destopt; |
| 86 | int len = ipv6_optlen(destopt); |
| 87 | int off = 0; |
| 88 | int optlen = 0; |
| 89 | |
| 90 | off += 2; |
| 91 | len -= 2; |
| 92 | |
| 93 | while (len > 0) { |
| 94 | |
| 95 | switch (opt[off]) { |
| 96 | |
| 97 | case IPV6_TLV_PAD0: |
| 98 | optlen = 1; |
| 99 | break; |
| 100 | default: |
| 101 | if (len < 2) |
| 102 | goto bad; |
| 103 | optlen = opt[off+1]+2; |
| 104 | if (len < optlen) |
| 105 | goto bad; |
| 106 | |
| 107 | /* Rearrange the source address in @iph and the |
| 108 | * addresses in home address option for final source. |
| 109 | * See 11.3.2 of RFC 3775 for details. |
| 110 | */ |
| 111 | if (opt[off] == IPV6_TLV_HAO) { |
| 112 | struct in6_addr final_addr; |
| 113 | struct ipv6_destopt_hao *hao; |
| 114 | |
| 115 | hao = (struct ipv6_destopt_hao *)&opt[off]; |
| 116 | if (hao->length != sizeof(hao->addr)) { |
| 117 | if (net_ratelimit()) |
| 118 | printk(KERN_WARNING "destopt hao: invalid header length: %u\n", hao->length); |
| 119 | goto bad; |
| 120 | } |
| 121 | ipv6_addr_copy(&final_addr, &hao->addr); |
| 122 | ipv6_addr_copy(&hao->addr, &iph->saddr); |
| 123 | ipv6_addr_copy(&iph->saddr, &final_addr); |
| 124 | } |
| 125 | break; |
| 126 | } |
| 127 | |
| 128 | off += optlen; |
| 129 | len -= optlen; |
| 130 | } |
YOSHIFUJI Hideaki | e731c24 | 2006-08-24 23:18:12 +0900 | [diff] [blame] | 131 | /* Note: ok if len == 0 */ |
Masahide NAKAMURA | 27637df | 2006-08-23 19:29:47 -0700 | [diff] [blame] | 132 | bad: |
| 133 | return; |
| 134 | } |
Masahide NAKAMURA | 136ebf0 | 2007-06-26 23:51:41 -0700 | [diff] [blame] | 135 | #else |
| 136 | static void ipv6_rearrange_destopt(struct ipv6hdr *iph, struct ipv6_opt_hdr *destopt) {} |
Masahide NAKAMURA | 27637df | 2006-08-23 19:29:47 -0700 | [diff] [blame] | 137 | #endif |
| 138 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 139 | /** |
| 140 | * ipv6_rearrange_rthdr - rearrange IPv6 routing header |
| 141 | * @iph: IPv6 header |
| 142 | * @rthdr: routing header |
| 143 | * |
| 144 | * Rearrange the destination address in @iph and the addresses in @rthdr |
| 145 | * so that they appear in the order they will at the final destination. |
| 146 | * See Appendix A2 of RFC 2402 for details. |
| 147 | */ |
| 148 | static void ipv6_rearrange_rthdr(struct ipv6hdr *iph, struct ipv6_rt_hdr *rthdr) |
| 149 | { |
| 150 | int segments, segments_left; |
| 151 | struct in6_addr *addrs; |
| 152 | struct in6_addr final_addr; |
| 153 | |
| 154 | segments_left = rthdr->segments_left; |
| 155 | if (segments_left == 0) |
| 156 | return; |
YOSHIFUJI Hideaki | 1ab1457 | 2007-02-09 23:24:49 +0900 | [diff] [blame] | 157 | rthdr->segments_left = 0; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 158 | |
| 159 | /* The value of rthdr->hdrlen has been verified either by the system |
| 160 | * call if it is locally generated, or by ipv6_rthdr_rcv() for incoming |
| 161 | * packets. So we can assume that it is even and that segments is |
| 162 | * greater than or equal to segments_left. |
| 163 | * |
| 164 | * For the same reason we can assume that this option is of type 0. |
| 165 | */ |
| 166 | segments = rthdr->hdrlen >> 1; |
| 167 | |
| 168 | addrs = ((struct rt0_hdr *)rthdr)->addr; |
| 169 | ipv6_addr_copy(&final_addr, addrs + segments - 1); |
| 170 | |
| 171 | addrs += segments - segments_left; |
| 172 | memmove(addrs + 1, addrs, (segments_left - 1) * sizeof(*addrs)); |
| 173 | |
| 174 | ipv6_addr_copy(addrs, &iph->daddr); |
| 175 | ipv6_addr_copy(&iph->daddr, &final_addr); |
| 176 | } |
| 177 | |
Masahide NAKAMURA | 27637df | 2006-08-23 19:29:47 -0700 | [diff] [blame] | 178 | static int ipv6_clear_mutable_options(struct ipv6hdr *iph, int len, int dir) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 179 | { |
| 180 | union { |
| 181 | struct ipv6hdr *iph; |
| 182 | struct ipv6_opt_hdr *opth; |
| 183 | struct ipv6_rt_hdr *rth; |
| 184 | char *raw; |
| 185 | } exthdr = { .iph = iph }; |
| 186 | char *end = exthdr.raw + len; |
| 187 | int nexthdr = iph->nexthdr; |
| 188 | |
| 189 | exthdr.iph++; |
| 190 | |
| 191 | while (exthdr.raw < end) { |
| 192 | switch (nexthdr) { |
Masahide NAKAMURA | 27637df | 2006-08-23 19:29:47 -0700 | [diff] [blame] | 193 | case NEXTHDR_DEST: |
| 194 | if (dir == XFRM_POLICY_OUT) |
| 195 | ipv6_rearrange_destopt(iph, exthdr.opth); |
YOSHIFUJI Hideaki | e731c24 | 2006-08-24 23:18:12 +0900 | [diff] [blame] | 196 | case NEXTHDR_HOP: |
| 197 | if (!zero_out_mutable_opts(exthdr.opth)) { |
| 198 | LIMIT_NETDEBUG( |
| 199 | KERN_WARNING "overrun %sopts\n", |
| 200 | nexthdr == NEXTHDR_HOP ? |
| 201 | "hop" : "dest"); |
| 202 | return -EINVAL; |
| 203 | } |
| 204 | break; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 205 | |
| 206 | case NEXTHDR_ROUTING: |
| 207 | ipv6_rearrange_rthdr(iph, exthdr.rth); |
| 208 | break; |
| 209 | |
| 210 | default : |
| 211 | return 0; |
| 212 | } |
| 213 | |
| 214 | nexthdr = exthdr.opth->nexthdr; |
| 215 | exthdr.raw += ipv6_optlen(exthdr.opth); |
| 216 | } |
| 217 | |
| 218 | return 0; |
| 219 | } |
| 220 | |
| 221 | static int ah6_output(struct xfrm_state *x, struct sk_buff *skb) |
| 222 | { |
| 223 | int err; |
| 224 | int extlen; |
| 225 | struct ipv6hdr *top_iph; |
| 226 | struct ip_auth_hdr *ah; |
| 227 | struct ah_data *ahp; |
| 228 | u8 nexthdr; |
| 229 | char tmp_base[8]; |
| 230 | struct { |
Masahide NAKAMURA | 59fbb3a6 | 2007-06-26 23:56:32 -0700 | [diff] [blame] | 231 | #if defined(CONFIG_IPV6_MIP6) || defined(CONFIG_IPV6_MIP6_MODULE) |
Masahide NAKAMURA | 27637df | 2006-08-23 19:29:47 -0700 | [diff] [blame] | 232 | struct in6_addr saddr; |
| 233 | #endif |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 234 | struct in6_addr daddr; |
| 235 | char hdrs[0]; |
| 236 | } *tmp_ext; |
| 237 | |
Herbert Xu | 7b277b1 | 2007-10-10 15:44:06 -0700 | [diff] [blame] | 238 | skb_push(skb, -skb_network_offset(skb)); |
Herbert Xu | 007f021 | 2007-10-09 13:25:59 -0700 | [diff] [blame] | 239 | top_iph = ipv6_hdr(skb); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 240 | top_iph->payload_len = htons(skb->len - sizeof(*top_iph)); |
| 241 | |
Herbert Xu | 007f021 | 2007-10-09 13:25:59 -0700 | [diff] [blame] | 242 | nexthdr = *skb_mac_header(skb); |
| 243 | *skb_mac_header(skb) = IPPROTO_AH; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 244 | |
| 245 | /* When there are no extension headers, we only need to save the first |
| 246 | * 8 bytes of the base IP header. |
| 247 | */ |
| 248 | memcpy(tmp_base, top_iph, sizeof(tmp_base)); |
| 249 | |
| 250 | tmp_ext = NULL; |
Kazunori MIYAZAWA | 144466b | 2007-05-25 01:22:25 -0700 | [diff] [blame] | 251 | extlen = skb_transport_offset(skb) - sizeof(struct ipv6hdr); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 252 | if (extlen) { |
| 253 | extlen += sizeof(*tmp_ext); |
| 254 | tmp_ext = kmalloc(extlen, GFP_ATOMIC); |
| 255 | if (!tmp_ext) { |
| 256 | err = -ENOMEM; |
| 257 | goto error; |
| 258 | } |
Masahide NAKAMURA | 59fbb3a6 | 2007-06-26 23:56:32 -0700 | [diff] [blame] | 259 | #if defined(CONFIG_IPV6_MIP6) || defined(CONFIG_IPV6_MIP6_MODULE) |
Masahide NAKAMURA | 27637df | 2006-08-23 19:29:47 -0700 | [diff] [blame] | 260 | memcpy(tmp_ext, &top_iph->saddr, extlen); |
YOSHIFUJI Hideaki | e731c24 | 2006-08-24 23:18:12 +0900 | [diff] [blame] | 261 | #else |
| 262 | memcpy(tmp_ext, &top_iph->daddr, extlen); |
| 263 | #endif |
Masahide NAKAMURA | 27637df | 2006-08-23 19:29:47 -0700 | [diff] [blame] | 264 | err = ipv6_clear_mutable_options(top_iph, |
| 265 | extlen - sizeof(*tmp_ext) + |
| 266 | sizeof(*top_iph), |
| 267 | XFRM_POLICY_OUT); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 268 | if (err) |
| 269 | goto error_free_iph; |
| 270 | } |
| 271 | |
Herbert Xu | 87bdc48 | 2007-10-10 15:45:25 -0700 | [diff] [blame] | 272 | ah = ip_auth_hdr(skb); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 273 | ah->nexthdr = nexthdr; |
| 274 | |
| 275 | top_iph->priority = 0; |
| 276 | top_iph->flow_lbl[0] = 0; |
| 277 | top_iph->flow_lbl[1] = 0; |
| 278 | top_iph->flow_lbl[2] = 0; |
| 279 | top_iph->hop_limit = 0; |
| 280 | |
| 281 | ahp = x->data; |
Herbert Xu | 87bdc48 | 2007-10-10 15:45:25 -0700 | [diff] [blame] | 282 | ah->hdrlen = (XFRM_ALIGN8(sizeof(*ah) + ahp->icv_trunc_len) >> 2) - 2; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 283 | |
| 284 | ah->reserved = 0; |
| 285 | ah->spi = x->id.spi; |
Herbert Xu | b318e0e | 2008-02-12 22:50:35 -0800 | [diff] [blame] | 286 | ah->seq_no = htonl(XFRM_SKB_CB(skb)->seq.output); |
Herbert Xu | b7c6538 | 2007-10-09 13:33:35 -0700 | [diff] [blame] | 287 | |
| 288 | spin_lock_bh(&x->lock); |
Herbert Xu | 07d4ee5 | 2006-08-20 14:24:50 +1000 | [diff] [blame] | 289 | err = ah_mac_digest(ahp, skb, ah->auth_data); |
Herbert Xu | b7c6538 | 2007-10-09 13:33:35 -0700 | [diff] [blame] | 290 | memcpy(ah->auth_data, ahp->work_icv, ahp->icv_trunc_len); |
| 291 | spin_unlock_bh(&x->lock); |
| 292 | |
Herbert Xu | 07d4ee5 | 2006-08-20 14:24:50 +1000 | [diff] [blame] | 293 | if (err) |
| 294 | goto error_free_iph; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 295 | |
| 296 | memcpy(top_iph, tmp_base, sizeof(tmp_base)); |
| 297 | if (tmp_ext) { |
Masahide NAKAMURA | 59fbb3a6 | 2007-06-26 23:56:32 -0700 | [diff] [blame] | 298 | #if defined(CONFIG_IPV6_MIP6) || defined(CONFIG_IPV6_MIP6_MODULE) |
Masahide NAKAMURA | 27637df | 2006-08-23 19:29:47 -0700 | [diff] [blame] | 299 | memcpy(&top_iph->saddr, tmp_ext, extlen); |
| 300 | #else |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 301 | memcpy(&top_iph->daddr, tmp_ext, extlen); |
Masahide NAKAMURA | 27637df | 2006-08-23 19:29:47 -0700 | [diff] [blame] | 302 | #endif |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 303 | error_free_iph: |
| 304 | kfree(tmp_ext); |
| 305 | } |
| 306 | |
| 307 | error: |
| 308 | return err; |
| 309 | } |
| 310 | |
Herbert Xu | e695633 | 2006-04-01 00:52:46 -0800 | [diff] [blame] | 311 | static int ah6_input(struct xfrm_state *x, struct sk_buff *skb) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 312 | { |
| 313 | /* |
| 314 | * Before process AH |
| 315 | * [IPv6][Ext1][Ext2][AH][Dest][Payload] |
| 316 | * |<-------------->| hdr_len |
| 317 | * |
| 318 | * To erase AH: |
| 319 | * Keeping copy of cleared headers. After AH processing, |
Arnaldo Carvalho de Melo | b0e380b | 2007-04-10 21:21:55 -0700 | [diff] [blame] | 320 | * Moving the pointer of skb->network_header by using skb_pull as long |
| 321 | * as AH header length. Then copy back the copy as long as hdr_len |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 322 | * If destination header following AH exists, copy it into after [Ext2]. |
YOSHIFUJI Hideaki | 1ab1457 | 2007-02-09 23:24:49 +0900 | [diff] [blame] | 323 | * |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 324 | * |<>|[IPv6][Ext1][Ext2][Dest][Payload] |
| 325 | * There is offset of AH before IPv6 header after the process. |
| 326 | */ |
| 327 | |
Herbert Xu | 87bdc48 | 2007-10-10 15:45:25 -0700 | [diff] [blame] | 328 | struct ip_auth_hdr *ah; |
Arnaldo Carvalho de Melo | 0660e03 | 2007-04-25 17:54:47 -0700 | [diff] [blame] | 329 | struct ipv6hdr *ip6h; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 330 | struct ah_data *ahp; |
| 331 | unsigned char *tmp_hdr = NULL; |
| 332 | u16 hdr_len; |
| 333 | u16 ah_hlen; |
| 334 | int nexthdr; |
Herbert Xu | 07d4ee5 | 2006-08-20 14:24:50 +1000 | [diff] [blame] | 335 | int err = -EINVAL; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 336 | |
| 337 | if (!pskb_may_pull(skb, sizeof(struct ip_auth_hdr))) |
| 338 | goto out; |
| 339 | |
| 340 | /* We are going to _remove_ AH header to keep sockets happy, |
| 341 | * so... Later this can change. */ |
| 342 | if (skb_cloned(skb) && |
| 343 | pskb_expand_head(skb, 0, 0, GFP_ATOMIC)) |
| 344 | goto out; |
| 345 | |
Herbert Xu | 7aa68cb | 2007-10-17 21:30:07 -0700 | [diff] [blame] | 346 | skb->ip_summed = CHECKSUM_NONE; |
| 347 | |
Arnaldo Carvalho de Melo | d56f90a | 2007-04-10 20:50:43 -0700 | [diff] [blame] | 348 | hdr_len = skb->data - skb_network_header(skb); |
Herbert Xu | 87bdc48 | 2007-10-10 15:45:25 -0700 | [diff] [blame] | 349 | ah = (struct ip_auth_hdr *)skb->data; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 350 | ahp = x->data; |
| 351 | nexthdr = ah->nexthdr; |
| 352 | ah_hlen = (ah->hdrlen + 2) << 2; |
| 353 | |
Herbert Xu | 87bdc48 | 2007-10-10 15:45:25 -0700 | [diff] [blame] | 354 | if (ah_hlen != XFRM_ALIGN8(sizeof(*ah) + ahp->icv_full_len) && |
| 355 | ah_hlen != XFRM_ALIGN8(sizeof(*ah) + ahp->icv_trunc_len)) |
YOSHIFUJI Hideaki | 1ab1457 | 2007-02-09 23:24:49 +0900 | [diff] [blame] | 356 | goto out; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 357 | |
| 358 | if (!pskb_may_pull(skb, ah_hlen)) |
| 359 | goto out; |
| 360 | |
Arnaldo Carvalho de Melo | d56f90a | 2007-04-10 20:50:43 -0700 | [diff] [blame] | 361 | tmp_hdr = kmemdup(skb_network_header(skb), hdr_len, GFP_ATOMIC); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 362 | if (!tmp_hdr) |
| 363 | goto out; |
Arnaldo Carvalho de Melo | 0660e03 | 2007-04-25 17:54:47 -0700 | [diff] [blame] | 364 | ip6h = ipv6_hdr(skb); |
| 365 | if (ipv6_clear_mutable_options(ip6h, hdr_len, XFRM_POLICY_IN)) |
Masahide NAKAMURA | 27637df | 2006-08-23 19:29:47 -0700 | [diff] [blame] | 366 | goto free_out; |
Arnaldo Carvalho de Melo | 0660e03 | 2007-04-25 17:54:47 -0700 | [diff] [blame] | 367 | ip6h->priority = 0; |
| 368 | ip6h->flow_lbl[0] = 0; |
| 369 | ip6h->flow_lbl[1] = 0; |
| 370 | ip6h->flow_lbl[2] = 0; |
| 371 | ip6h->hop_limit = 0; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 372 | |
Herbert Xu | 0ebea8e | 2007-11-13 21:45:58 -0800 | [diff] [blame] | 373 | spin_lock(&x->lock); |
YOSHIFUJI Hideaki | 1ab1457 | 2007-02-09 23:24:49 +0900 | [diff] [blame] | 374 | { |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 375 | u8 auth_data[MAX_AH_AUTH_LEN]; |
| 376 | |
| 377 | memcpy(auth_data, ah->auth_data, ahp->icv_trunc_len); |
| 378 | memset(ah->auth_data, 0, ahp->icv_trunc_len); |
Herbert Xu | 31a4ab9 | 2006-05-27 23:06:13 -0700 | [diff] [blame] | 379 | skb_push(skb, hdr_len); |
Herbert Xu | 07d4ee5 | 2006-08-20 14:24:50 +1000 | [diff] [blame] | 380 | err = ah_mac_digest(ahp, skb, ah->auth_data); |
| 381 | if (err) |
Herbert Xu | 0ebea8e | 2007-11-13 21:45:58 -0800 | [diff] [blame] | 382 | goto unlock; |
Herbert Xu | 9dd3245 | 2007-12-30 21:10:30 -0800 | [diff] [blame] | 383 | if (memcmp(ahp->work_icv, auth_data, ahp->icv_trunc_len)) |
Herbert Xu | 668dc8a | 2007-12-16 15:55:02 -0800 | [diff] [blame] | 384 | err = -EBADMSG; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 385 | } |
Herbert Xu | 0ebea8e | 2007-11-13 21:45:58 -0800 | [diff] [blame] | 386 | unlock: |
| 387 | spin_unlock(&x->lock); |
| 388 | |
| 389 | if (err) |
| 390 | goto free_out; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 391 | |
Arnaldo Carvalho de Melo | b0e380b | 2007-04-10 21:21:55 -0700 | [diff] [blame] | 392 | skb->network_header += ah_hlen; |
Arnaldo Carvalho de Melo | d56f90a | 2007-04-10 20:50:43 -0700 | [diff] [blame] | 393 | memcpy(skb_network_header(skb), tmp_hdr, hdr_len); |
Arnaldo Carvalho de Melo | b0e380b | 2007-04-10 21:21:55 -0700 | [diff] [blame] | 394 | skb->transport_header = skb->network_header; |
Herbert Xu | 31a4ab9 | 2006-05-27 23:06:13 -0700 | [diff] [blame] | 395 | __skb_pull(skb, ah_hlen + hdr_len); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 396 | |
| 397 | kfree(tmp_hdr); |
| 398 | |
| 399 | return nexthdr; |
| 400 | |
| 401 | free_out: |
| 402 | kfree(tmp_hdr); |
| 403 | out: |
Herbert Xu | 07d4ee5 | 2006-08-20 14:24:50 +1000 | [diff] [blame] | 404 | return err; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 405 | } |
| 406 | |
YOSHIFUJI Hideaki | 1ab1457 | 2007-02-09 23:24:49 +0900 | [diff] [blame] | 407 | static void ah6_err(struct sk_buff *skb, struct inet6_skb_parm *opt, |
| 408 | int type, int code, int offset, __be32 info) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 409 | { |
| 410 | struct ipv6hdr *iph = (struct ipv6hdr*)skb->data; |
| 411 | struct ip_auth_hdr *ah = (struct ip_auth_hdr*)(skb->data+offset); |
| 412 | struct xfrm_state *x; |
| 413 | |
| 414 | if (type != ICMPV6_DEST_UNREACH && |
| 415 | type != ICMPV6_PKT_TOOBIG) |
| 416 | return; |
| 417 | |
| 418 | x = xfrm_state_lookup((xfrm_address_t *)&iph->daddr, ah->spi, IPPROTO_AH, AF_INET6); |
| 419 | if (!x) |
| 420 | return; |
| 421 | |
Harvey Harrison | 5b095d989 | 2008-10-29 12:52:50 -0700 | [diff] [blame] | 422 | NETDEBUG(KERN_DEBUG "pmtu discovery on SA AH/%08x/%pI6\n", |
Harvey Harrison | 0c6ce78 | 2008-10-28 16:09:23 -0700 | [diff] [blame] | 423 | ntohl(ah->spi), &iph->daddr); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 424 | |
| 425 | xfrm_state_put(x); |
| 426 | } |
| 427 | |
Herbert Xu | 72cb696 | 2005-06-20 13:18:08 -0700 | [diff] [blame] | 428 | static int ah6_init_state(struct xfrm_state *x) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 429 | { |
| 430 | struct ah_data *ahp = NULL; |
| 431 | struct xfrm_algo_desc *aalg_desc; |
Herbert Xu | 07d4ee5 | 2006-08-20 14:24:50 +1000 | [diff] [blame] | 432 | struct crypto_hash *tfm; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 433 | |
| 434 | if (!x->aalg) |
| 435 | goto error; |
| 436 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 437 | if (x->encap) |
| 438 | goto error; |
| 439 | |
Ingo Oeser | 0c600ed | 2006-03-20 23:01:32 -0800 | [diff] [blame] | 440 | ahp = kzalloc(sizeof(*ahp), GFP_KERNEL); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 441 | if (ahp == NULL) |
| 442 | return -ENOMEM; |
| 443 | |
Herbert Xu | 07d4ee5 | 2006-08-20 14:24:50 +1000 | [diff] [blame] | 444 | tfm = crypto_alloc_hash(x->aalg->alg_name, 0, CRYPTO_ALG_ASYNC); |
| 445 | if (IS_ERR(tfm)) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 446 | goto error; |
Herbert Xu | 07d4ee5 | 2006-08-20 14:24:50 +1000 | [diff] [blame] | 447 | |
| 448 | ahp->tfm = tfm; |
Herbert Xu | bc31d3b | 2007-10-08 17:14:34 -0700 | [diff] [blame] | 449 | if (crypto_hash_setkey(tfm, x->aalg->alg_key, |
| 450 | (x->aalg->alg_key_len + 7) / 8)) |
Herbert Xu | 07d4ee5 | 2006-08-20 14:24:50 +1000 | [diff] [blame] | 451 | goto error; |
YOSHIFUJI Hideaki | 1ab1457 | 2007-02-09 23:24:49 +0900 | [diff] [blame] | 452 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 453 | /* |
| 454 | * Lookup the algorithm description maintained by xfrm_algo, |
| 455 | * verify crypto transform properties, and store information |
| 456 | * we need for AH processing. This lookup cannot fail here |
Herbert Xu | 07d4ee5 | 2006-08-20 14:24:50 +1000 | [diff] [blame] | 457 | * after a successful crypto_alloc_hash(). |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 458 | */ |
| 459 | aalg_desc = xfrm_aalg_get_byname(x->aalg->alg_name, 0); |
| 460 | BUG_ON(!aalg_desc); |
| 461 | |
| 462 | if (aalg_desc->uinfo.auth.icv_fullbits/8 != |
Herbert Xu | 07d4ee5 | 2006-08-20 14:24:50 +1000 | [diff] [blame] | 463 | crypto_hash_digestsize(tfm)) { |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 464 | printk(KERN_INFO "AH: %s digestsize %u != %hu\n", |
Herbert Xu | 07d4ee5 | 2006-08-20 14:24:50 +1000 | [diff] [blame] | 465 | x->aalg->alg_name, crypto_hash_digestsize(tfm), |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 466 | aalg_desc->uinfo.auth.icv_fullbits/8); |
| 467 | goto error; |
| 468 | } |
YOSHIFUJI Hideaki | 1ab1457 | 2007-02-09 23:24:49 +0900 | [diff] [blame] | 469 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 470 | ahp->icv_full_len = aalg_desc->uinfo.auth.icv_fullbits/8; |
| 471 | ahp->icv_trunc_len = aalg_desc->uinfo.auth.icv_truncbits/8; |
YOSHIFUJI Hideaki | 1ab1457 | 2007-02-09 23:24:49 +0900 | [diff] [blame] | 472 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 473 | BUG_ON(ahp->icv_trunc_len > MAX_AH_AUTH_LEN); |
YOSHIFUJI Hideaki | 1ab1457 | 2007-02-09 23:24:49 +0900 | [diff] [blame] | 474 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 475 | ahp->work_icv = kmalloc(ahp->icv_full_len, GFP_KERNEL); |
| 476 | if (!ahp->work_icv) |
| 477 | goto error; |
YOSHIFUJI Hideaki | 1ab1457 | 2007-02-09 23:24:49 +0900 | [diff] [blame] | 478 | |
Herbert Xu | 87bdc48 | 2007-10-10 15:45:25 -0700 | [diff] [blame] | 479 | x->props.header_len = XFRM_ALIGN8(sizeof(struct ip_auth_hdr) + |
| 480 | ahp->icv_trunc_len); |
Herbert Xu | ca68145 | 2007-10-17 21:35:15 -0700 | [diff] [blame] | 481 | switch (x->props.mode) { |
| 482 | case XFRM_MODE_BEET: |
| 483 | case XFRM_MODE_TRANSPORT: |
| 484 | break; |
| 485 | case XFRM_MODE_TUNNEL: |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 486 | x->props.header_len += sizeof(struct ipv6hdr); |
Masahide NAKAMURA | ea2c47b | 2007-10-22 02:30:15 -0700 | [diff] [blame] | 487 | break; |
Herbert Xu | ca68145 | 2007-10-17 21:35:15 -0700 | [diff] [blame] | 488 | default: |
| 489 | goto error; |
| 490 | } |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 491 | x->data = ahp; |
| 492 | |
| 493 | return 0; |
| 494 | |
| 495 | error: |
| 496 | if (ahp) { |
Jesper Juhl | 573dbd9 | 2005-09-01 17:44:29 -0700 | [diff] [blame] | 497 | kfree(ahp->work_icv); |
Herbert Xu | 07d4ee5 | 2006-08-20 14:24:50 +1000 | [diff] [blame] | 498 | crypto_free_hash(ahp->tfm); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 499 | kfree(ahp); |
| 500 | } |
| 501 | return -EINVAL; |
| 502 | } |
| 503 | |
| 504 | static void ah6_destroy(struct xfrm_state *x) |
| 505 | { |
| 506 | struct ah_data *ahp = x->data; |
| 507 | |
| 508 | if (!ahp) |
| 509 | return; |
| 510 | |
Jesper Juhl | 573dbd9 | 2005-09-01 17:44:29 -0700 | [diff] [blame] | 511 | kfree(ahp->work_icv); |
| 512 | ahp->work_icv = NULL; |
Herbert Xu | 07d4ee5 | 2006-08-20 14:24:50 +1000 | [diff] [blame] | 513 | crypto_free_hash(ahp->tfm); |
Jesper Juhl | 573dbd9 | 2005-09-01 17:44:29 -0700 | [diff] [blame] | 514 | ahp->tfm = NULL; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 515 | kfree(ahp); |
| 516 | } |
| 517 | |
Eric Dumazet | 533cb5b | 2008-01-30 19:11:50 -0800 | [diff] [blame] | 518 | static const struct xfrm_type ah6_type = |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 519 | { |
| 520 | .description = "AH6", |
| 521 | .owner = THIS_MODULE, |
| 522 | .proto = IPPROTO_AH, |
Herbert Xu | 436a0a4 | 2007-10-08 17:25:53 -0700 | [diff] [blame] | 523 | .flags = XFRM_TYPE_REPLAY_PROT, |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 524 | .init_state = ah6_init_state, |
| 525 | .destructor = ah6_destroy, |
| 526 | .input = ah6_input, |
Masahide NAKAMURA | aee5adb | 2006-08-23 17:57:28 -0700 | [diff] [blame] | 527 | .output = ah6_output, |
| 528 | .hdr_offset = xfrm6_find_1stfragopt, |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 529 | }; |
| 530 | |
| 531 | static struct inet6_protocol ah6_protocol = { |
| 532 | .handler = xfrm6_rcv, |
| 533 | .err_handler = ah6_err, |
| 534 | .flags = INET6_PROTO_NOPOLICY, |
| 535 | }; |
| 536 | |
| 537 | static int __init ah6_init(void) |
| 538 | { |
| 539 | if (xfrm_register_type(&ah6_type, AF_INET6) < 0) { |
| 540 | printk(KERN_INFO "ipv6 ah init: can't add xfrm type\n"); |
| 541 | return -EAGAIN; |
| 542 | } |
| 543 | |
| 544 | if (inet6_add_protocol(&ah6_protocol, IPPROTO_AH) < 0) { |
| 545 | printk(KERN_INFO "ipv6 ah init: can't add protocol\n"); |
| 546 | xfrm_unregister_type(&ah6_type, AF_INET6); |
| 547 | return -EAGAIN; |
| 548 | } |
| 549 | |
| 550 | return 0; |
| 551 | } |
| 552 | |
| 553 | static void __exit ah6_fini(void) |
| 554 | { |
| 555 | if (inet6_del_protocol(&ah6_protocol, IPPROTO_AH) < 0) |
| 556 | printk(KERN_INFO "ipv6 ah close: can't remove protocol\n"); |
| 557 | |
| 558 | if (xfrm_unregister_type(&ah6_type, AF_INET6) < 0) |
| 559 | printk(KERN_INFO "ipv6 ah close: can't remove xfrm type\n"); |
| 560 | |
| 561 | } |
| 562 | |
| 563 | module_init(ah6_init); |
| 564 | module_exit(ah6_fini); |
| 565 | |
| 566 | MODULE_LICENSE("GPL"); |
Masahide NAKAMURA | d3d6dd3 | 2007-06-26 23:57:49 -0700 | [diff] [blame] | 567 | MODULE_ALIAS_XFRM_TYPE(AF_INET6, XFRM_PROTO_AH); |