ikev2_common.c

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#include "includes.h"

#include "common.h"
#include "sha1.h"
#include "md5.h"
#include "crypto.h"
#include "ikev2_common.h"


static struct ikev2_integ_alg ikev2_integ_algs[] = {
        { AUTH_HMAC_SHA1_96, 20, 12 },
        { AUTH_HMAC_MD5_96, 16, 12 }
};

#define NUM_INTEG_ALGS (sizeof(ikev2_integ_algs) / sizeof(ikev2_integ_algs[0]))


static struct ikev2_prf_alg ikev2_prf_algs[] = {
        { PRF_HMAC_SHA1, 20, 20 },
        { PRF_HMAC_MD5, 16, 16 }
};

#define NUM_PRF_ALGS (sizeof(ikev2_prf_algs) / sizeof(ikev2_prf_algs[0]))


static struct ikev2_encr_alg ikev2_encr_algs[] = {
        { ENCR_AES_CBC, 16, 16 }, /* only 128-bit keys supported for now */
        { ENCR_3DES, 24, 8 }
};

#define NUM_ENCR_ALGS (sizeof(ikev2_encr_algs) / sizeof(ikev2_encr_algs[0]))


const struct ikev2_integ_alg * ikev2_get_integ(int id)
{
        size_t i;

        for (i = 0; i < NUM_INTEG_ALGS; i++) {
                if (ikev2_integ_algs[i].id == id)
                        return &ikev2_integ_algs[i];
        }

        return NULL;
}


int ikev2_integ_hash(int alg, const u8 *key, size_t key_len, const u8 *data,
                     size_t data_len, u8 *hash)
{
        u8 tmphash[IKEV2_MAX_HASH_LEN];

        switch (alg) {
        case AUTH_HMAC_SHA1_96:
                if (key_len != 20)
                        return -1;
                hmac_sha1(key, key_len, data, data_len, tmphash);
                os_memcpy(hash, tmphash, 12);
                break;
        case AUTH_HMAC_MD5_96:
                if (key_len != 16)
                        return -1;
                hmac_md5(key, key_len, data, data_len, tmphash);
                os_memcpy(hash, tmphash, 12);
                break;
        default:
                return -1;
        }

        return 0;
}


const struct ikev2_prf_alg * ikev2_get_prf(int id)
{
        size_t i;

        for (i = 0; i < NUM_PRF_ALGS; i++) {
                if (ikev2_prf_algs[i].id == id)
                        return &ikev2_prf_algs[i];
        }

        return NULL;
}


int ikev2_prf_hash(int alg, const u8 *key, size_t key_len,
                   size_t num_elem, const u8 *addr[], const size_t *len,
                   u8 *hash)
{
        switch (alg) {
        case PRF_HMAC_SHA1:
                hmac_sha1_vector(key, key_len, num_elem, addr, len, hash);
                break;
        case PRF_HMAC_MD5:
                hmac_md5_vector(key, key_len, num_elem, addr, len, hash);
                break;
        default:
                return -1;
        }

        return 0;
}


int ikev2_prf_plus(int alg, const u8 *key, size_t key_len,
                   const u8 *data, size_t data_len,
                   u8 *out, size_t out_len)
{
        u8 hash[IKEV2_MAX_HASH_LEN];
        size_t hash_len;
        u8 iter, *pos, *end;
        const u8 *addr[3];
        size_t len[3];
        const struct ikev2_prf_alg *prf;
        int res;

        prf = ikev2_get_prf(alg);
        if (prf == NULL)
                return -1;
        hash_len = prf->hash_len;

        addr[0] = hash;
        len[0] = hash_len;
        addr[1] = data;
        len[1] = data_len;
        addr[2] = &iter;
        len[2] = 1;

        pos = out;
        end = out + out_len;
        iter = 1;
        while (pos < end) {
                size_t clen;
                if (iter == 1)
                        res = ikev2_prf_hash(alg, key, key_len, 2, &addr[1],
                                             &len[1], hash);
                else
                        res = ikev2_prf_hash(alg, key, key_len, 3, addr, len,
                                             hash);
                if (res < 0)
                        return -1;
                clen = hash_len;
                if ((int) clen > end - pos)
                        clen = end - pos;
                os_memcpy(pos, hash, clen);
                pos += clen;
                iter++;
        }

        return 0;
}


const struct ikev2_encr_alg * ikev2_get_encr(int id)
{
        size_t i;

        for (i = 0; i < NUM_ENCR_ALGS; i++) {
                if (ikev2_encr_algs[i].id == id)
                        return &ikev2_encr_algs[i];
        }

        return NULL;
}


#ifdef CCNS_PL
/* from des.c */
struct des3_key_s {
        u32 ek[3][32];
        u32 dk[3][32];
};

void des3_key_setup(const u8 *key, struct des3_key_s *dkey);
void des3_encrypt(const u8 *plain, const struct des3_key_s *key, u8 *crypt);
void des3_decrypt(const u8 *crypt, const struct des3_key_s *key, u8 *plain);
#endif /* CCNS_PL */


int ikev2_encr_encrypt(int alg, const u8 *key, size_t key_len, const u8 *iv,
                       const u8 *plain, u8 *crypt, size_t len)
{
        struct crypto_cipher *cipher;
        int encr_alg;

#ifdef CCNS_PL
        if (alg == ENCR_3DES) {
                struct des3_key_s des3key;
                size_t i, blocks;
                u8 *pos;

                /* ECB mode is used incorrectly for 3DES!? */
                if (key_len != 24) {
                        wpa_printf(MSG_INFO, "IKEV2: Invalid encr key length");
                        return -1;
                }
                des3_key_setup(key, &des3key);

                blocks = len / 8;
                pos = crypt;
                for (i = 0; i < blocks; i++) {
                        des3_encrypt(pos, &des3key, pos);
                        pos += 8;
                }
        } else {
#endif /* CCNS_PL */
        switch (alg) {
        case ENCR_3DES:
                encr_alg = CRYPTO_CIPHER_ALG_3DES;
                break;
        case ENCR_AES_CBC:
                encr_alg = CRYPTO_CIPHER_ALG_AES;
                break;
        default:
                wpa_printf(MSG_DEBUG, "IKEV2: Unsupported encr alg %d", alg);
                return -1;
        }

        cipher = crypto_cipher_init(encr_alg, iv, key, key_len);
        if (cipher == NULL) {
                wpa_printf(MSG_INFO, "IKEV2: Failed to initialize cipher");
                return -1;
        }

        if (crypto_cipher_encrypt(cipher, plain, crypt, len) < 0) {
                wpa_printf(MSG_INFO, "IKEV2: Encryption failed");
                crypto_cipher_deinit(cipher);
                return -1;
        }
        crypto_cipher_deinit(cipher);
#ifdef CCNS_PL
        }
#endif /* CCNS_PL */

        return 0;
}


int ikev2_encr_decrypt(int alg, const u8 *key, size_t key_len, const u8 *iv,
                       const u8 *crypt, u8 *plain, size_t len)
{
        struct crypto_cipher *cipher;
        int encr_alg;

#ifdef CCNS_PL
        if (alg == ENCR_3DES) {
                struct des3_key_s des3key;
                size_t i, blocks;

                /* ECB mode is used incorrectly for 3DES!? */
                if (key_len != 24) {
                        wpa_printf(MSG_INFO, "IKEV2: Invalid encr key length");
                        return -1;
                }
                des3_key_setup(key, &des3key);

                if (len % 8) {
                        wpa_printf(MSG_INFO, "IKEV2: Invalid encrypted "
                                   "length");
                        return -1;
                }
                blocks = len / 8;
                for (i = 0; i < blocks; i++) {
                        des3_decrypt(crypt, &des3key, plain);
                        plain += 8;
                        crypt += 8;
                }
        } else {
#endif /* CCNS_PL */
        switch (alg) {
        case ENCR_3DES:
                encr_alg = CRYPTO_CIPHER_ALG_3DES;
                break;
        case ENCR_AES_CBC:
                encr_alg = CRYPTO_CIPHER_ALG_AES;
                break;
        default:
                wpa_printf(MSG_DEBUG, "IKEV2: Unsupported encr alg %d", alg);
                return -1;
        }

        cipher = crypto_cipher_init(encr_alg, iv, key, key_len);
        if (cipher == NULL) {
                wpa_printf(MSG_INFO, "IKEV2: Failed to initialize cipher");
                return -1;
        }

        if (crypto_cipher_decrypt(cipher, crypt, plain, len) < 0) {
                wpa_printf(MSG_INFO, "IKEV2: Decryption failed");
                crypto_cipher_deinit(cipher);
                return -1;
        }
        crypto_cipher_deinit(cipher);
#ifdef CCNS_PL
        }
#endif /* CCNS_PL */

        return 0;
}


int ikev2_parse_payloads(struct ikev2_payloads *payloads,
                         u8 next_payload, const u8 *pos, const u8 *end)
{
        const struct ikev2_payload_hdr *phdr;

        os_memset(payloads, 0, sizeof(*payloads));

        while (next_payload != IKEV2_PAYLOAD_NO_NEXT_PAYLOAD) {
                int plen, pdatalen;
                const u8 *pdata;
                wpa_printf(MSG_DEBUG, "IKEV2: Processing payload %u",
                           next_payload);
                if (end - pos < (int) sizeof(*phdr)) {
                        wpa_printf(MSG_INFO, "IKEV2:   Too short message for "
                                   "payload header (left=%ld)",
                                   (long) (end - pos));
                }
                phdr = (const struct ikev2_payload_hdr *) pos;
                plen = WPA_GET_BE16(phdr->payload_length);
                if (plen < (int) sizeof(*phdr) || pos + plen > end) {
                        wpa_printf(MSG_INFO, "IKEV2:   Invalid payload header "
                                   "length %d", plen);
                        return -1;
                }

                wpa_printf(MSG_DEBUG, "IKEV2:   Next Payload: %u  Flags: 0x%x"
                           "  Payload Length: %d",
                           phdr->next_payload, phdr->flags, plen);

                pdata = (const u8 *) (phdr + 1);
                pdatalen = plen - sizeof(*phdr);

                switch (next_payload) {
                case IKEV2_PAYLOAD_SA:
                        wpa_printf(MSG_DEBUG, "IKEV2:   Payload: Security "
                                   "Association");
                        payloads->sa = pdata;
                        payloads->sa_len = pdatalen;
                        break;
                case IKEV2_PAYLOAD_KEY_EXCHANGE:
                        wpa_printf(MSG_DEBUG, "IKEV2:   Payload: Key "
                                   "Exchange");
                        payloads->ke = pdata;
                        payloads->ke_len = pdatalen;
                        break;
                case IKEV2_PAYLOAD_IDi:
                        wpa_printf(MSG_DEBUG, "IKEV2:   Payload: IDi");
                        payloads->idi = pdata;
                        payloads->idi_len = pdatalen;
                        break;
                case IKEV2_PAYLOAD_IDr:
                        wpa_printf(MSG_DEBUG, "IKEV2:   Payload: IDr");
                        payloads->idr = pdata;
                        payloads->idr_len = pdatalen;
                        break;
                case IKEV2_PAYLOAD_CERTIFICATE:
                        wpa_printf(MSG_DEBUG, "IKEV2:   Payload: Certificate");
                        payloads->cert = pdata;
                        payloads->cert_len = pdatalen;
                        break;
                case IKEV2_PAYLOAD_AUTHENTICATION:
                        wpa_printf(MSG_DEBUG, "IKEV2:   Payload: "
                                   "Authentication");
                        payloads->auth = pdata;
                        payloads->auth_len = pdatalen;
                        break;
                case IKEV2_PAYLOAD_NONCE:
                        wpa_printf(MSG_DEBUG, "IKEV2:   Payload: Nonce");
                        payloads->nonce = pdata;
                        payloads->nonce_len = pdatalen;
                        break;
                case IKEV2_PAYLOAD_ENCRYPTED:
                        wpa_printf(MSG_DEBUG, "IKEV2:   Payload: Encrypted");
                        payloads->encrypted = pdata;
                        payloads->encrypted_len = pdatalen;
                        break;
                case IKEV2_PAYLOAD_NOTIFICATION:
                        wpa_printf(MSG_DEBUG, "IKEV2:   Payload: "
                                   "Notification");
                        payloads->notification = pdata;
                        payloads->notification_len = pdatalen;
                        break;
                default:
                        if (phdr->flags & IKEV2_PAYLOAD_FLAGS_CRITICAL) {
                                wpa_printf(MSG_INFO, "IKEV2:   Unsupported "
                                           "critical payload %u - reject the "
                                           "entire message", next_payload);
                                return -1;
                        } else {
                                wpa_printf(MSG_DEBUG, "IKEV2:   Skipped "
                                           "unsupported payload %u",
                                           next_payload);
                        }
                }

                if (next_payload == IKEV2_PAYLOAD_ENCRYPTED &&
                    pos + plen == end) {
                        /*
                         * Next Payload in the case of Encrypted Payload is
                         * actually the payload type for the first embedded
                         * payload.
                         */
                        payloads->encr_next_payload = phdr->next_payload;
                        next_payload = IKEV2_PAYLOAD_NO_NEXT_PAYLOAD;
                } else
                        next_payload = phdr->next_payload;

                pos += plen;
        }

        if (pos != end) {
                wpa_printf(MSG_INFO, "IKEV2: Unexpected extra data after "
                           "payloads");
                return -1;
        }

        return 0;
}


int ikev2_derive_auth_data(int prf_alg, const struct wpabuf *sign_msg,
                           const u8 *ID, size_t ID_len, u8 ID_type,
                           struct ikev2_keys *keys, int initiator,
                           const u8 *shared_secret, size_t shared_secret_len,
                           const u8 *nonce, size_t nonce_len,
                           const u8 *key_pad, size_t key_pad_len,
                           u8 *auth_data)
{
        size_t sign_len, buf_len;
        u8 *sign_data, *pos, *buf, hash[IKEV2_MAX_HASH_LEN];
        const struct ikev2_prf_alg *prf;
        const u8 *SK_p = initiator ? keys->SK_pi : keys->SK_pr;

        prf = ikev2_get_prf(prf_alg);
        if (sign_msg == NULL || ID == NULL || SK_p == NULL ||
            shared_secret == NULL || nonce == NULL || prf == NULL)
                return -1;

        /* prf(SK_pi/r,IDi/r') */
        buf_len = 4 + ID_len;
        buf = os_zalloc(buf_len);
        if (buf == NULL)
                return -1;
        buf[0] = ID_type;
        os_memcpy(buf + 4, ID, ID_len);
        if (ikev2_prf_hash(prf->id, SK_p, keys->SK_prf_len,
                           1, (const u8 **) &buf, &buf_len, hash) < 0) {
                os_free(buf);
                return -1;
        }
        os_free(buf);

        /* sign_data = msg | Nr/i | prf(SK_pi/r,IDi/r') */
        sign_len = wpabuf_len(sign_msg) + nonce_len + prf->hash_len;
        sign_data = os_malloc(sign_len);
        if (sign_data == NULL)
                return -1;
        pos = sign_data;
        os_memcpy(pos, wpabuf_head(sign_msg), wpabuf_len(sign_msg));
        pos += wpabuf_len(sign_msg);
        os_memcpy(pos, nonce, nonce_len);
        pos += nonce_len;
        os_memcpy(pos, hash, prf->hash_len);

        /* AUTH = prf(prf(Shared Secret, key pad, sign_data) */
        if (ikev2_prf_hash(prf->id, shared_secret, shared_secret_len, 1,
                           &key_pad, &key_pad_len, hash) < 0 ||
            ikev2_prf_hash(prf->id, hash, prf->hash_len, 1,
                           (const u8 **) &sign_data, &sign_len, auth_data) < 0)
        {
                os_free(sign_data);
                return -1;
        }
        os_free(sign_data);

        return 0;
}


u8 * ikev2_decrypt_payload(int encr_id, int integ_id,
                           struct ikev2_keys *keys, int initiator,
                           const struct ikev2_hdr *hdr,
                           const u8 *encrypted, size_t encrypted_len,
                           size_t *res_len)
{
        size_t iv_len;
        const u8 *pos, *end, *iv, *integ;
        u8 hash[IKEV2_MAX_HASH_LEN], *decrypted;
        size_t decrypted_len, pad_len;
        const struct ikev2_integ_alg *integ_alg;
        const struct ikev2_encr_alg *encr_alg;
        const u8 *SK_e = initiator ? keys->SK_ei : keys->SK_er;
        const u8 *SK_a = initiator ? keys->SK_ai : keys->SK_ar;

        if (encrypted == NULL) {
                wpa_printf(MSG_INFO, "IKEV2: No Encrypted payload in SA_AUTH");
                return NULL;
        }

        encr_alg = ikev2_get_encr(encr_id);
        if (encr_alg == NULL) {
                wpa_printf(MSG_INFO, "IKEV2: Unsupported encryption type");
                return NULL;
        }
        iv_len = encr_alg->block_size;

        integ_alg = ikev2_get_integ(integ_id);
        if (integ_alg == NULL) {
                wpa_printf(MSG_INFO, "IKEV2: Unsupported intergrity type");
                return NULL;
        }

        if (encrypted_len < iv_len + 1 + integ_alg->hash_len) {
                wpa_printf(MSG_INFO, "IKEV2: No room for IV or Integrity "
                          "Checksum");
                return NULL;
        }

        iv = encrypted;
        pos = iv + iv_len;
        end = encrypted + encrypted_len;
        integ = end - integ_alg->hash_len;

        if (SK_a == NULL) {
                wpa_printf(MSG_INFO, "IKEV2: No SK_a available");
                return NULL;
        }
        if (ikev2_integ_hash(integ_id, SK_a, keys->SK_integ_len,
                             (const u8 *) hdr,
                             integ - (const u8 *) hdr, hash) < 0) {
                wpa_printf(MSG_INFO, "IKEV2: Failed to calculate integrity "
                           "hash");
                return NULL;
        }
        if (os_memcmp(integ, hash, integ_alg->hash_len) != 0) {
                wpa_printf(MSG_INFO, "IKEV2: Incorrect Integrity Checksum "
                           "Data");
                return NULL;
        }

        if (SK_e == NULL) {
                wpa_printf(MSG_INFO, "IKEV2: No SK_e available");
                return NULL;
        }

        decrypted_len = integ - pos;
        decrypted = os_malloc(decrypted_len);
        if (decrypted == NULL)
                return NULL;

        if (ikev2_encr_decrypt(encr_alg->id, SK_e, keys->SK_encr_len, iv, pos,
                               decrypted, decrypted_len) < 0) {
                os_free(decrypted);
                return NULL;
        }

        pad_len = decrypted[decrypted_len - 1];
        if (decrypted_len < pad_len + 1) {
                wpa_printf(MSG_INFO, "IKEV2: Invalid padding in encrypted "
                           "payload");
                os_free(decrypted);
                return NULL;
        }

        decrypted_len -= pad_len + 1;

        *res_len = decrypted_len;
        return decrypted;
}


void ikev2_update_hdr(struct wpabuf *msg)
{
        struct ikev2_hdr *hdr;

        /* Update lenth field in HDR */
        hdr = wpabuf_mhead(msg);
        WPA_PUT_BE32(hdr->length, wpabuf_len(msg));
}


int ikev2_build_encrypted(int encr_id, int integ_id, struct ikev2_keys *keys,
                          int initiator, struct wpabuf *msg,
                          struct wpabuf *plain, u8 next_payload)
{
        struct ikev2_payload_hdr *phdr;
        size_t plen;
        size_t iv_len, pad_len;
        u8 *icv, *iv;
        const struct ikev2_integ_alg *integ_alg;
        const struct ikev2_encr_alg *encr_alg;
        const u8 *SK_e = initiator ? keys->SK_ei : keys->SK_er;
        const u8 *SK_a = initiator ? keys->SK_ai : keys->SK_ar;

        wpa_printf(MSG_DEBUG, "IKEV2: Adding Encrypted payload");

        /* Encr - RFC 4306, Sect. 3.14 */

        encr_alg = ikev2_get_encr(encr_id);
        if (encr_alg == NULL) {
                wpa_printf(MSG_INFO, "IKEV2: Unsupported encryption type");
                return -1;
        }
        iv_len = encr_alg->block_size;

        integ_alg = ikev2_get_integ(integ_id);
        if (integ_alg == NULL) {
                wpa_printf(MSG_INFO, "IKEV2: Unsupported intergrity type");
                return -1;
        }

        if (SK_e == NULL) {
                wpa_printf(MSG_INFO, "IKEV2: No SK_e available");
                return -1;
        }

        if (SK_a == NULL) {
                wpa_printf(MSG_INFO, "IKEV2: No SK_a available");
                return -1;
        }

        phdr = wpabuf_put(msg, sizeof(*phdr));
        phdr->next_payload = next_payload;
        phdr->flags = 0;

        iv = wpabuf_put(msg, iv_len);
        if (os_get_random(iv, iv_len)) {
                wpa_printf(MSG_INFO, "IKEV2: Could not generate IV");
                return -1;
        }

        pad_len = iv_len - (wpabuf_len(plain) + 1) % iv_len;
        if (pad_len == iv_len)
                pad_len = 0;
        wpabuf_put(plain, pad_len);
        wpabuf_put_u8(plain, pad_len);

        if (ikev2_encr_encrypt(encr_alg->id, SK_e, keys->SK_encr_len, iv,
                               wpabuf_head(plain), wpabuf_mhead(plain),
                               wpabuf_len(plain)) < 0)
                return -1;

        wpabuf_put_buf(msg, plain);

        /* Need to update all headers (Length fields) prior to hash func */
        icv = wpabuf_put(msg, integ_alg->hash_len);
        plen = (u8 *) wpabuf_put(msg, 0) - (u8 *) phdr;
        WPA_PUT_BE16(phdr->payload_length, plen);

        ikev2_update_hdr(msg);

        return ikev2_integ_hash(integ_id, SK_a, keys->SK_integ_len,
                                wpabuf_head(msg),
                                wpabuf_len(msg) - integ_alg->hash_len, icv);

        return 0;
}


int ikev2_keys_set(struct ikev2_keys *keys)
{
        return keys->SK_d && keys->SK_ai && keys->SK_ar && keys->SK_ei &&
                keys->SK_er && keys->SK_pi && keys->SK_pr;
}


void ikev2_free_keys(struct ikev2_keys *keys)
{
        os_free(keys->SK_d);
        os_free(keys->SK_ai);
        os_free(keys->SK_ar);
        os_free(keys->SK_ei);
        os_free(keys->SK_er);
        os_free(keys->SK_pi);
        os_free(keys->SK_pr);
        keys->SK_d = keys->SK_ai = keys->SK_ar = keys->SK_ei = keys->SK_er =
                keys->SK_pi = keys->SK_pr = NULL;
}


int ikev2_derive_sk_keys(const struct ikev2_prf_alg *prf,
                         const struct ikev2_integ_alg *integ,
                         const struct ikev2_encr_alg *encr,
                         const u8 *skeyseed, const u8 *data, size_t data_len,
                         struct ikev2_keys *keys)
{
        u8 *keybuf, *pos;
        size_t keybuf_len;

        /*
         * {SK_d | SK_ai | SK_ar | SK_ei | SK_er | SK_pi | SK_pr } =
         *      prf+(SKEYSEED, Ni | Nr | SPIi | SPIr )
         */
        ikev2_free_keys(keys);
        keys->SK_d_len = prf->key_len;
        keys->SK_integ_len = integ->key_len;
        keys->SK_encr_len = encr->key_len;
        keys->SK_prf_len = prf->key_len;
#ifdef CCNS_PL
        /* Uses encryption key length for SK_d; should be PRF length */
        keys->SK_d_len = keys->SK_encr_len;
#endif /* CCNS_PL */

        keybuf_len = keys->SK_d_len + 2 * keys->SK_integ_len +
                2 * keys->SK_encr_len + 2 * keys->SK_prf_len;
        keybuf = os_malloc(keybuf_len);
        if (keybuf == NULL)
                return -1;

        if (ikev2_prf_plus(prf->id, skeyseed, prf->hash_len,
                           data, data_len, keybuf, keybuf_len)) {
                os_free(keybuf);
                return -1;
        }

        pos = keybuf;

        keys->SK_d = os_malloc(keys->SK_d_len);
        if (keys->SK_d) {
                os_memcpy(keys->SK_d, pos, keys->SK_d_len);
                wpa_hexdump_key(MSG_DEBUG, "IKEV2: SK_d",
                                keys->SK_d, keys->SK_d_len);
        }
        pos += keys->SK_d_len;

        keys->SK_ai = os_malloc(keys->SK_integ_len);
        if (keys->SK_ai) {
                os_memcpy(keys->SK_ai, pos, keys->SK_integ_len);
                wpa_hexdump_key(MSG_DEBUG, "IKEV2: SK_ai",
                                keys->SK_ai, keys->SK_integ_len);
        }
        pos += keys->SK_integ_len;

        keys->SK_ar = os_malloc(keys->SK_integ_len);
        if (keys->SK_ar) {
                os_memcpy(keys->SK_ar, pos, keys->SK_integ_len);
                wpa_hexdump_key(MSG_DEBUG, "IKEV2: SK_ar",
                                keys->SK_ar, keys->SK_integ_len);
        }
        pos += keys->SK_integ_len;

        keys->SK_ei = os_malloc(keys->SK_encr_len);
        if (keys->SK_ei) {
                os_memcpy(keys->SK_ei, pos, keys->SK_encr_len);
                wpa_hexdump_key(MSG_DEBUG, "IKEV2: SK_ei",
                                keys->SK_ei, keys->SK_encr_len);
        }
        pos += keys->SK_encr_len;

        keys->SK_er = os_malloc(keys->SK_encr_len);
        if (keys->SK_er) {
                os_memcpy(keys->SK_er, pos, keys->SK_encr_len);
                wpa_hexdump_key(MSG_DEBUG, "IKEV2: SK_er",
                                keys->SK_er, keys->SK_encr_len);
        }
        pos += keys->SK_encr_len;

        keys->SK_pi = os_malloc(keys->SK_prf_len);
        if (keys->SK_pi) {
                os_memcpy(keys->SK_pi, pos, keys->SK_prf_len);
                wpa_hexdump_key(MSG_DEBUG, "IKEV2: SK_pi",
                                keys->SK_pi, keys->SK_prf_len);
        }
        pos += keys->SK_prf_len;

        keys->SK_pr = os_malloc(keys->SK_prf_len);
        if (keys->SK_pr) {
                os_memcpy(keys->SK_pr, pos, keys->SK_prf_len);
                wpa_hexdump_key(MSG_DEBUG, "IKEV2: SK_pr",
                                keys->SK_pr, keys->SK_prf_len);
        }

        os_free(keybuf);

        if (!ikev2_keys_set(keys)) {
                ikev2_free_keys(keys);
                return -1;
        }

        return 0;
}