1 // SPDX-License-Identifier: GPL-2.0 2 /* 3 * xfrm6_state.c: based on xfrm4_state.c 4 * 5 * Authors: 6 * Mitsuru KANDA @USAGI 7 * Kazunori MIYAZAWA @USAGI 8 * Kunihiro Ishiguro <kunihiro@ipinfusion.com> 9 * IPv6 support 10 * YOSHIFUJI Hideaki @USAGI 11 * Split up af-specific portion 12 * 13 */ 14 15 #include <net/xfrm.h> 16 #include <linux/pfkeyv2.h> 17 #include <linux/ipsec.h> 18 #include <linux/netfilter_ipv6.h> 19 #include <linux/export.h> 20 #include <net/dsfield.h> 21 #include <net/ipv6.h> 22 #include <net/addrconf.h> 23 24 static void 25 __xfrm6_init_tempsel(struct xfrm_selector *sel, const struct flowi *fl) 26 { 27 const struct flowi6 *fl6 = &fl->u.ip6; 28 29 /* Initialize temporary selector matching only 30 * to current session. */ 31 *(struct in6_addr *)&sel->daddr = fl6->daddr; 32 *(struct in6_addr *)&sel->saddr = fl6->saddr; 33 sel->dport = xfrm_flowi_dport(fl, &fl6->uli); 34 sel->dport_mask = htons(0xffff); 35 sel->sport = xfrm_flowi_sport(fl, &fl6->uli); 36 sel->sport_mask = htons(0xffff); 37 sel->family = AF_INET6; 38 sel->prefixlen_d = 128; 39 sel->prefixlen_s = 128; 40 sel->proto = fl6->flowi6_proto; 41 sel->ifindex = fl6->flowi6_oif; 42 } 43 44 static void 45 xfrm6_init_temprop(struct xfrm_state *x, const struct xfrm_tmpl *tmpl, 46 const xfrm_address_t *daddr, const xfrm_address_t *saddr) 47 { 48 x->id = tmpl->id; 49 if (ipv6_addr_any((struct in6_addr *)&x->id.daddr)) 50 memcpy(&x->id.daddr, daddr, sizeof(x->sel.daddr)); 51 memcpy(&x->props.saddr, &tmpl->saddr, sizeof(x->props.saddr)); 52 if (ipv6_addr_any((struct in6_addr *)&x->props.saddr)) 53 memcpy(&x->props.saddr, saddr, sizeof(x->props.saddr)); 54 x->props.mode = tmpl->mode; 55 x->props.reqid = tmpl->reqid; 56 x->props.family = AF_INET6; 57 } 58 59 /* distribution counting sort function for xfrm_state and xfrm_tmpl */ 60 static int 61 __xfrm6_sort(void **dst, void **src, int n, int (*cmp)(void *p), int maxclass) 62 { 63 int i; 64 int class[XFRM_MAX_DEPTH]; 65 int count[maxclass]; 66 67 memset(count, 0, sizeof(count)); 68 69 for (i = 0; i < n; i++) { 70 int c; 71 class[i] = c = cmp(src[i]); 72 count[c]++; 73 } 74 75 for (i = 2; i < maxclass; i++) 76 count[i] += count[i - 1]; 77 78 for (i = 0; i < n; i++) { 79 dst[count[class[i] - 1]++] = src[i]; 80 src[i] = NULL; 81 } 82 83 return 0; 84 } 85 86 /* 87 * Rule for xfrm_state: 88 * 89 * rule 1: select IPsec transport except AH 90 * rule 2: select MIPv6 RO or inbound trigger 91 * rule 3: select IPsec transport AH 92 * rule 4: select IPsec tunnel 93 * rule 5: others 94 */ 95 static int __xfrm6_state_sort_cmp(void *p) 96 { 97 struct xfrm_state *v = p; 98 99 switch (v->props.mode) { 100 case XFRM_MODE_TRANSPORT: 101 if (v->id.proto != IPPROTO_AH) 102 return 1; 103 else 104 return 3; 105 #if IS_ENABLED(CONFIG_IPV6_MIP6) 106 case XFRM_MODE_ROUTEOPTIMIZATION: 107 case XFRM_MODE_IN_TRIGGER: 108 return 2; 109 #endif 110 case XFRM_MODE_TUNNEL: 111 case XFRM_MODE_BEET: 112 return 4; 113 } 114 return 5; 115 } 116 117 static int 118 __xfrm6_state_sort(struct xfrm_state **dst, struct xfrm_state **src, int n) 119 { 120 return __xfrm6_sort((void **)dst, (void **)src, n, 121 __xfrm6_state_sort_cmp, 6); 122 } 123 124 /* 125 * Rule for xfrm_tmpl: 126 * 127 * rule 1: select IPsec transport 128 * rule 2: select MIPv6 RO or inbound trigger 129 * rule 3: select IPsec tunnel 130 * rule 4: others 131 */ 132 static int __xfrm6_tmpl_sort_cmp(void *p) 133 { 134 struct xfrm_tmpl *v = p; 135 switch (v->mode) { 136 case XFRM_MODE_TRANSPORT: 137 return 1; 138 #if IS_ENABLED(CONFIG_IPV6_MIP6) 139 case XFRM_MODE_ROUTEOPTIMIZATION: 140 case XFRM_MODE_IN_TRIGGER: 141 return 2; 142 #endif 143 case XFRM_MODE_TUNNEL: 144 case XFRM_MODE_BEET: 145 return 3; 146 } 147 return 4; 148 } 149 150 static int 151 __xfrm6_tmpl_sort(struct xfrm_tmpl **dst, struct xfrm_tmpl **src, int n) 152 { 153 return __xfrm6_sort((void **)dst, (void **)src, n, 154 __xfrm6_tmpl_sort_cmp, 5); 155 } 156 157 int xfrm6_extract_header(struct sk_buff *skb) 158 { 159 struct ipv6hdr *iph = ipv6_hdr(skb); 160 161 XFRM_MODE_SKB_CB(skb)->ihl = sizeof(*iph); 162 XFRM_MODE_SKB_CB(skb)->id = 0; 163 XFRM_MODE_SKB_CB(skb)->frag_off = htons(IP_DF); 164 XFRM_MODE_SKB_CB(skb)->tos = ipv6_get_dsfield(iph); 165 XFRM_MODE_SKB_CB(skb)->ttl = iph->hop_limit; 166 XFRM_MODE_SKB_CB(skb)->optlen = 0; 167 memcpy(XFRM_MODE_SKB_CB(skb)->flow_lbl, iph->flow_lbl, 168 sizeof(XFRM_MODE_SKB_CB(skb)->flow_lbl)); 169 170 return 0; 171 } 172 173 static struct xfrm_state_afinfo xfrm6_state_afinfo = { 174 .family = AF_INET6, 175 .proto = IPPROTO_IPV6, 176 .eth_proto = htons(ETH_P_IPV6), 177 .owner = THIS_MODULE, 178 .init_tempsel = __xfrm6_init_tempsel, 179 .init_temprop = xfrm6_init_temprop, 180 .tmpl_sort = __xfrm6_tmpl_sort, 181 .state_sort = __xfrm6_state_sort, 182 .output = xfrm6_output, 183 .output_finish = xfrm6_output_finish, 184 .extract_input = xfrm6_extract_input, 185 .extract_output = xfrm6_extract_output, 186 .transport_finish = xfrm6_transport_finish, 187 .local_error = xfrm6_local_error, 188 }; 189 190 int __init xfrm6_state_init(void) 191 { 192 return xfrm_state_register_afinfo(&xfrm6_state_afinfo); 193 } 194 195 void xfrm6_state_fini(void) 196 { 197 xfrm_state_unregister_afinfo(&xfrm6_state_afinfo); 198 } 199 200