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 count[XFRM_MAX_DEPTH] = { }; 64 int class[XFRM_MAX_DEPTH]; 65 int i; 66 67 for (i = 0; i < n; i++) { 68 int c; 69 class[i] = c = cmp(src[i]); 70 count[c]++; 71 } 72 73 for (i = 2; i < maxclass; i++) 74 count[i] += count[i - 1]; 75 76 for (i = 0; i < n; i++) { 77 dst[count[class[i] - 1]++] = src[i]; 78 src[i] = NULL; 79 } 80 81 return 0; 82 } 83 84 /* 85 * Rule for xfrm_state: 86 * 87 * rule 1: select IPsec transport except AH 88 * rule 2: select MIPv6 RO or inbound trigger 89 * rule 3: select IPsec transport AH 90 * rule 4: select IPsec tunnel 91 * rule 5: others 92 */ 93 static int __xfrm6_state_sort_cmp(void *p) 94 { 95 struct xfrm_state *v = p; 96 97 switch (v->props.mode) { 98 case XFRM_MODE_TRANSPORT: 99 if (v->id.proto != IPPROTO_AH) 100 return 1; 101 else 102 return 3; 103 #if IS_ENABLED(CONFIG_IPV6_MIP6) 104 case XFRM_MODE_ROUTEOPTIMIZATION: 105 case XFRM_MODE_IN_TRIGGER: 106 return 2; 107 #endif 108 case XFRM_MODE_TUNNEL: 109 case XFRM_MODE_BEET: 110 return 4; 111 } 112 return 5; 113 } 114 115 static int 116 __xfrm6_state_sort(struct xfrm_state **dst, struct xfrm_state **src, int n) 117 { 118 return __xfrm6_sort((void **)dst, (void **)src, n, 119 __xfrm6_state_sort_cmp, 6); 120 } 121 122 /* 123 * Rule for xfrm_tmpl: 124 * 125 * rule 1: select IPsec transport 126 * rule 2: select MIPv6 RO or inbound trigger 127 * rule 3: select IPsec tunnel 128 * rule 4: others 129 */ 130 static int __xfrm6_tmpl_sort_cmp(void *p) 131 { 132 struct xfrm_tmpl *v = p; 133 switch (v->mode) { 134 case XFRM_MODE_TRANSPORT: 135 return 1; 136 #if IS_ENABLED(CONFIG_IPV6_MIP6) 137 case XFRM_MODE_ROUTEOPTIMIZATION: 138 case XFRM_MODE_IN_TRIGGER: 139 return 2; 140 #endif 141 case XFRM_MODE_TUNNEL: 142 case XFRM_MODE_BEET: 143 return 3; 144 } 145 return 4; 146 } 147 148 static int 149 __xfrm6_tmpl_sort(struct xfrm_tmpl **dst, struct xfrm_tmpl **src, int n) 150 { 151 return __xfrm6_sort((void **)dst, (void **)src, n, 152 __xfrm6_tmpl_sort_cmp, 5); 153 } 154 155 int xfrm6_extract_header(struct sk_buff *skb) 156 { 157 struct ipv6hdr *iph = ipv6_hdr(skb); 158 159 XFRM_MODE_SKB_CB(skb)->ihl = sizeof(*iph); 160 XFRM_MODE_SKB_CB(skb)->id = 0; 161 XFRM_MODE_SKB_CB(skb)->frag_off = htons(IP_DF); 162 XFRM_MODE_SKB_CB(skb)->tos = ipv6_get_dsfield(iph); 163 XFRM_MODE_SKB_CB(skb)->ttl = iph->hop_limit; 164 XFRM_MODE_SKB_CB(skb)->optlen = 0; 165 memcpy(XFRM_MODE_SKB_CB(skb)->flow_lbl, iph->flow_lbl, 166 sizeof(XFRM_MODE_SKB_CB(skb)->flow_lbl)); 167 168 return 0; 169 } 170 171 static struct xfrm_state_afinfo xfrm6_state_afinfo = { 172 .family = AF_INET6, 173 .proto = IPPROTO_IPV6, 174 .eth_proto = htons(ETH_P_IPV6), 175 .owner = THIS_MODULE, 176 .init_tempsel = __xfrm6_init_tempsel, 177 .init_temprop = xfrm6_init_temprop, 178 .tmpl_sort = __xfrm6_tmpl_sort, 179 .state_sort = __xfrm6_state_sort, 180 .output = xfrm6_output, 181 .output_finish = xfrm6_output_finish, 182 .extract_input = xfrm6_extract_input, 183 .extract_output = xfrm6_extract_output, 184 .transport_finish = xfrm6_transport_finish, 185 .local_error = xfrm6_local_error, 186 }; 187 188 int __init xfrm6_state_init(void) 189 { 190 return xfrm_state_register_afinfo(&xfrm6_state_afinfo); 191 } 192 193 void xfrm6_state_fini(void) 194 { 195 xfrm_state_unregister_afinfo(&xfrm6_state_afinfo); 196 } 197