contrib/hostapd/src/eap_common/eap_ikev2_common.c

   1 /*
   2  * EAP-IKEv2 common routines
   3  * Copyright (c) 2007, Jouni Malinen <j@w1.fi>
   4  *
   5  * This program is free software; you can redistribute it and/or modify
   6  * it under the terms of the GNU General Public License version 2 as
   7  * published by the Free Software Foundation.
   8  *
   9  * Alternatively, this software may be distributed under the terms of BSD
  10  * license.
  11  *
  12  * See README and COPYING for more details.
  13  */
  14
  15 #include "includes.h"
  16
  17 #include "common.h"
  18 #include "eap_defs.h"
  19 #include "eap_common.h"
  20 #include "ikev2_common.h"
  21 #include "eap_ikev2_common.h"
  22
  23
  24 int eap_ikev2_derive_keymat(int prf, struct ikev2_keys *keys,
  25                             const u8 *i_nonce, size_t i_nonce_len,
  26                             const u8 *r_nonce, size_t r_nonce_len,
  27                             u8 *keymat)
  28 {
  29         u8 *nonces;
  30         size_t nlen;
  31
  32         /* KEYMAT = prf+(SK_d, Ni | Nr) */
  33         if (keys->SK_d == NULL || i_nonce == NULL || r_nonce == NULL)
  34                 return -1;
  35
  36         nlen = i_nonce_len + r_nonce_len;
  37         nonces = os_malloc(nlen);
  38         if (nonces == NULL)
  39                 return -1;
  40         os_memcpy(nonces, i_nonce, i_nonce_len);
  41         os_memcpy(nonces + i_nonce_len, r_nonce, r_nonce_len);
  42
  43         if (ikev2_prf_plus(prf, keys->SK_d, keys->SK_d_len, nonces, nlen,
  44                            keymat, EAP_MSK_LEN + EAP_EMSK_LEN)) {
  45                 os_free(nonces);
  46                 return -1;
  47         }
  48         os_free(nonces);
  49
  50         wpa_hexdump_key(MSG_DEBUG, "EAP-IKEV2: KEYMAT",
  51                         keymat, EAP_MSK_LEN + EAP_EMSK_LEN);
  52
  53         return 0;
  54 }
  55
  56
  57 struct wpabuf * eap_ikev2_build_frag_ack(u8 id, u8 code)
  58 {
  59         struct wpabuf *msg;
  60
  61 #ifdef CCNS_PL
  62         msg = eap_msg_alloc(EAP_VENDOR_IETF, EAP_TYPE_IKEV2, 1, code, id);
  63         if (msg == NULL) {
  64                 wpa_printf(MSG_ERROR, "EAP-IKEV2: Failed to allocate memory "
  65                            "for fragment ack");
  66                 return NULL;
  67         }
  68         wpabuf_put_u8(msg, 0); /* Flags */
  69 #else /* CCNS_PL */
  70         msg = eap_msg_alloc(EAP_VENDOR_IETF, EAP_TYPE_IKEV2, 0, code, id);
  71         if (msg == NULL) {
  72                 wpa_printf(MSG_ERROR, "EAP-IKEV2: Failed to allocate memory "
  73                            "for fragment ack");
  74                 return NULL;
  75         }
  76 #endif /* CCNS_PL */
  77
  78         wpa_printf(MSG_DEBUG, "EAP-IKEV2: Send fragment ack");
  79
  80         return msg;
  81 }
  82
  83
  84 int eap_ikev2_validate_icv(int integ_alg, struct ikev2_keys *keys,
  85                            int initiator, const struct wpabuf *msg,
  86                            const u8 *pos, const u8 *end)
  87 {
  88         const struct ikev2_integ_alg *integ;
  89         size_t icv_len;
  90         u8 icv[IKEV2_MAX_HASH_LEN];
  91         const u8 *SK_a = initiator ? keys->SK_ai : keys->SK_ar;
  92
  93         integ = ikev2_get_integ(integ_alg);
  94         if (integ == NULL) {
  95                 wpa_printf(MSG_DEBUG, "EAP-IKEV2: Unknown INTEG "
  96                            "transform / cannot validate ICV");
  97                 return -1;
  98         }
  99         icv_len = integ->hash_len;
 100
 101         if (end - pos < (int) icv_len) {
 102                 wpa_printf(MSG_DEBUG, "EAP-IKEV2: Not enough room in the "
 103                            "message for Integrity Checksum Data");
 104                 return -1;
 105         }
 106
 107         if (SK_a == NULL) {
 108                 wpa_printf(MSG_DEBUG, "EAP-IKEV2: No SK_a for ICV validation");
 109                 return -1;
 110         }
 111
 112         if (ikev2_integ_hash(integ_alg, SK_a, keys->SK_integ_len,
 113                              wpabuf_head(msg),
 114                              wpabuf_len(msg) - icv_len, icv) < 0) {
 115                 wpa_printf(MSG_INFO, "EAP-IKEV2: Could not calculate ICV");
 116                 return -1;
 117         }
 118
 119         if (os_memcmp(icv, end - icv_len, icv_len) != 0) {
 120                 wpa_printf(MSG_INFO, "EAP-IKEV2: Invalid ICV");
 121                 wpa_hexdump(MSG_DEBUG, "EAP-IKEV2: Calculated ICV",
 122                             icv, icv_len);
 123                 wpa_hexdump(MSG_DEBUG, "EAP-IKEV2: Received ICV",
 124                             end - icv_len, icv_len);
 125                 return -1;
 126         }
 127
 128         wpa_printf(MSG_DEBUG, "EAP-IKEV2: Valid Integrity Checksum Data in "
 129                    "the received message");
 130
 131         return icv_len;
 132 }