EAP-pwd: Add support for EAP-pwd server and peer functionality
authorDan Harkins <dharkins@lounge.org>
Wed, 15 Sep 2010 07:51:40 +0000 (21:51 -1000)
committerJouni Malinen <j@w1.fi>
Wed, 15 Sep 2010 07:51:40 +0000 (21:51 -1000)
This adds an initial EAP-pwd (RFC 5931) implementation. For now,
this requires OpenSSL.

23 files changed:
hostapd/Makefile
hostapd/config_file.c
hostapd/eap_register.c
src/ap/ap_config.c
src/ap/ap_config.h
src/ap/authsrv.c
src/ap/ieee802_1x.c
src/eap_common/eap_defs.h
src/eap_common/eap_pwd_common.c [new file with mode: 0644]
src/eap_common/eap_pwd_common.h [new file with mode: 0644]
src/eap_peer/eap_methods.h
src/eap_peer/eap_pwd.c [new file with mode: 0644]
src/eap_server/eap.h
src/eap_server/eap_i.h
src/eap_server/eap_methods.h
src/eap_server/eap_server.c
src/eap_server/eap_server_pwd.c [new file with mode: 0644]
src/eapol_auth/eapol_auth_sm.c
src/eapol_auth/eapol_auth_sm.h
src/radius/radius_server.c
src/radius/radius_server.h
wpa_supplicant/Makefile
wpa_supplicant/eap_register.c

index 6102c10..f43f4a5 100644 (file)
@@ -274,6 +274,12 @@ NEED_SHA256=y
 NEED_AES_OMAC1=y
 endif
 
+ifdef CONFIG_EAP_PWD
+CFLAGS += -DEAP_SERVER_PWD
+OBJS += ../src/eap_server/eap_server_pwd.o ../src/eap_common/eap_pwd_common.o
+NEED_SHA256=y
+endif
+
 ifdef CONFIG_EAP_VENDOR_TEST
 CFLAGS += -DEAP_SERVER_VENDOR_TEST
 OBJS += ../src/eap_server/eap_server_vendor_test.o
index 0032504..5ff6add 100644 (file)
@@ -1369,6 +1369,10 @@ struct hostapd_config * hostapd_config_read(const char *fname)
                } else if (os_strcmp(buf, "tnc") == 0) {
                        bss->tnc = atoi(pos);
 #endif /* EAP_SERVER_TNC */
+#ifdef EAP_SERVER_PWD
+               } else if (os_strcmp(buf, "pwd_group") == 0) {
+                       bss->pwd_group = atoi(pos);
+#endif /* EAP_SERVER_PWD */
 #endif /* EAP_SERVER */
                } else if (os_strcmp(buf, "eap_message") == 0) {
                        char *term;
index ae9bf9d..bab2871 100644 (file)
@@ -130,5 +130,10 @@ int eap_server_register_methods(void)
                ret = eap_server_tnc_register();
 #endif /* EAP_SERVER_TNC */
 
+#ifdef EAP_SERVER_PWD
+       if (ret == 0)
+               ret = eap_server_pwd_register();
+#endif /* EAP_SERVER_PWD */
+
        return ret;
 }
index 5996993..702cb76 100644 (file)
@@ -74,6 +74,8 @@ void hostapd_config_defaults_bss(struct hostapd_bss_config *bss)
 
        bss->max_listen_interval = 65535;
 
+       bss->pwd_group = 19; /* ECC: GF(p=256) */
+
 #ifdef CONFIG_IEEE80211W
        bss->assoc_sa_query_max_timeout = 1000;
        bss->assoc_sa_query_retry_timeout = 201;
index 8bf7192..fc74d80 100644 (file)
@@ -255,6 +255,7 @@ struct hostapd_bss_config {
        int eap_sim_aka_result_ind;
        int tnc;
        int fragment_size;
+       u16 pwd_group;
 
        char *radius_server_clients;
        int radius_server_auth_port;
index 0ab0668..7c87fde 100644 (file)
@@ -119,6 +119,7 @@ static int hostapd_setup_radius_srv(struct hostapd_data *hapd)
        srv.get_eap_user = hostapd_radius_get_eap_user;
        srv.eap_req_id_text = conf->eap_req_id_text;
        srv.eap_req_id_text_len = conf->eap_req_id_text_len;
+       srv.pwd_group = conf->pwd_group;
 
        hapd->radius_srv = radius_server_init(&srv);
        if (hapd->radius_srv == NULL) {
index c0ece64..a935816 100644 (file)
@@ -1652,6 +1652,7 @@ int ieee802_1x_init(struct hostapd_data *hapd)
        conf.tnc = hapd->conf->tnc;
        conf.wps = hapd->wps;
        conf.fragment_size = hapd->conf->fragment_size;
+       conf.pwd_group = hapd->conf->pwd_group;
 
        os_memset(&cb, 0, sizeof(cb));
        cb.eapol_send = ieee802_1x_eapol_send;
index 0efe7ab..3035301 100644 (file)
@@ -68,6 +68,7 @@ typedef enum {
        EAP_TYPE_IKEV2 = 49 /* RFC 5106 */,
        EAP_TYPE_AKA_PRIME = 50 /* draft-arkko-eap-aka-kdf-10.txt */,
        EAP_TYPE_GPSK = 51 /* RFC 5433 */,
+       EAP_TYPE_PWD = 52 /* RFC 5931 */,
        EAP_TYPE_EXPANDED = 254 /* RFC 3748 */
 } EapType;
 
diff --git a/src/eap_common/eap_pwd_common.c b/src/eap_common/eap_pwd_common.c
new file mode 100644 (file)
index 0000000..d01ba0a
--- /dev/null
@@ -0,0 +1,344 @@
+/*
+ * EAP server/peer: EAP-pwd shared routines
+ * Copyright (c) 2010, Dan Harkins <dharkins@lounge.org>
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the BSD license.
+ *
+ * Alternatively, this software may be distributed under the terms of the
+ * GNU General Public License version 2 as published by the Free Software
+ * Foundation.
+ *
+ * See README and COPYING for more details.
+ */
+
+#include "includes.h"
+#include "common.h"
+#include "eap_defs.h"
+#include "eap_pwd_common.h"
+
+/* The random function H(x) = HMAC-SHA256(0^32, x) */
+void H_Init(HMAC_CTX *ctx)
+{
+       u8 allzero[SHA256_DIGEST_LENGTH];
+
+       os_memset(allzero, 0, SHA256_DIGEST_LENGTH);
+       HMAC_Init(ctx, allzero, SHA256_DIGEST_LENGTH, EVP_sha256());
+}
+
+
+void H_Update(HMAC_CTX *ctx, const u8 *data, int len)
+{
+       HMAC_Update(ctx, data, len);
+}
+
+
+void H_Final(HMAC_CTX *ctx, u8 *digest)
+{
+       unsigned int mdlen = SHA256_DIGEST_LENGTH;
+
+       HMAC_Final(ctx, digest, &mdlen);
+       HMAC_CTX_cleanup(ctx);
+}
+
+
+/* a counter-based KDF based on NIST SP800-108 */
+void eap_pwd_kdf(u8 *key, int keylen, u8 *label, int labellen,
+                u8 *result, int resultbitlen)
+{
+       HMAC_CTX hctx;
+       unsigned char digest[SHA256_DIGEST_LENGTH];
+       u16 i, ctr, L;
+       int resultbytelen, len = 0;
+       unsigned int mdlen = SHA256_DIGEST_LENGTH;
+       unsigned char mask = 0xff;
+
+       resultbytelen = (resultbitlen + 7)/8;
+       ctr = 0;
+       L = htons(resultbitlen);
+       while (len < resultbytelen) {
+               ctr++; i = htons(ctr);
+               HMAC_Init(&hctx, key, keylen, EVP_sha256());
+               if (ctr > 1)
+                       HMAC_Update(&hctx, digest, mdlen);
+               HMAC_Update(&hctx, (u8 *) &i, sizeof(u16));
+               HMAC_Update(&hctx, label, labellen);
+               HMAC_Update(&hctx, (u8 *) &L, sizeof(u16));
+               HMAC_Final(&hctx, digest, &mdlen);
+               if ((len + (int) mdlen) > resultbytelen)
+                       os_memcpy(result + len, digest, resultbytelen - len);
+               else
+                       os_memcpy(result + len, digest, mdlen);
+               len += mdlen;
+               HMAC_CTX_cleanup(&hctx);
+       }
+
+       /* since we're expanding to a bit length, mask off the excess */
+       if (resultbitlen % 8) {
+               mask >>= ((resultbytelen * 8) - resultbitlen);
+               result[0] &= mask;
+       }
+}
+
+
+/*
+ * compute a "random" secret point on an elliptic curve based
+ * on the password and identities.
+ */
+int compute_password_element(EAP_PWD_group *grp, u16 num,
+                            u8 *password, int password_len,
+                            u8 *id_server, int id_server_len,
+                            u8 *id_peer, int id_peer_len, u8 *token)
+{
+       BIGNUM *x_candidate = NULL, *rnd = NULL, *cofactor = NULL;
+       HMAC_CTX ctx;
+       unsigned char pwe_digest[SHA256_DIGEST_LENGTH], *prfbuf = NULL, ctr;
+       int nid, is_odd, primebitlen, primebytelen, ret = 0;
+
+       switch (num) { /* from IANA registry for IKE D-H groups */
+        case 19:
+               nid = NID_X9_62_prime256v1;
+               break;
+        case 20:
+               nid = NID_secp384r1;
+               break;
+        case 21:
+               nid = NID_secp521r1;
+               break;
+        case 25:
+               nid = NID_X9_62_prime192v1;
+               break;
+        case 26:
+               nid = NID_secp224r1;
+               break;
+        default:
+               wpa_printf(MSG_INFO, "EAP-pwd: unsupported group %d", num);
+               return -1;
+       }
+
+       grp->pwe = NULL;
+       grp->order = NULL;
+       grp->prime = NULL;
+
+       if ((grp->group = EC_GROUP_new_by_curve_name(nid)) == NULL) {
+               wpa_printf(MSG_INFO, "EAP-pwd: unable to create EC_GROUP");
+               goto fail;
+       }
+
+       if (((rnd = BN_new()) == NULL) ||
+           ((cofactor = BN_new()) == NULL) ||
+           ((grp->pwe = EC_POINT_new(grp->group)) == NULL) ||
+           ((grp->order = BN_new()) == NULL) ||
+           ((grp->prime = BN_new()) == NULL) ||
+           ((x_candidate = BN_new()) == NULL)) {
+               wpa_printf(MSG_INFO, "EAP-pwd: unable to create bignums");
+               goto fail;
+       }
+
+       if (!EC_GROUP_get_curve_GFp(grp->group, grp->prime, NULL, NULL, NULL))
+       {
+               wpa_printf(MSG_INFO, "EAP-pwd: unable to get prime for GFp "
+                          "curve");
+               goto fail;
+       }
+       if (!EC_GROUP_get_order(grp->group, grp->order, NULL)) {
+               wpa_printf(MSG_INFO, "EAP-pwd: unable to get order for curve");
+               goto fail;
+       }
+       if (!EC_GROUP_get_cofactor(grp->group, cofactor, NULL)) {
+               wpa_printf(MSG_INFO, "EAP-pwd: unable to get cofactor for "
+                          "curve");
+               goto fail;
+       }
+       primebitlen = BN_num_bits(grp->prime);
+       primebytelen = BN_num_bytes(grp->prime);
+       if ((prfbuf = os_malloc(primebytelen)) == NULL) {
+               wpa_printf(MSG_INFO, "EAP-pwd: unable to malloc space for prf "
+                          "buffer");
+               goto fail;
+       }
+       os_memset(prfbuf, 0, primebytelen);
+       ctr = 0;
+       while (1) {
+               if (ctr > 10) {
+                       wpa_printf(MSG_INFO, "EAP-pwd: unable to find random "
+                                  "point on curve for group %d, something's "
+                                  "fishy", num);
+                       goto fail;
+               }
+               ctr++;
+
+               /*
+                * compute counter-mode password value and stretch to prime
+                *    pwd-seed = H(token | peer-id | server-id | password |
+                *                 counter)
+                */
+               H_Init(&ctx);
+               H_Update(&ctx, token, sizeof(u32));
+               H_Update(&ctx, id_peer, id_peer_len);
+               H_Update(&ctx, id_server, id_server_len);
+               H_Update(&ctx, password, password_len);
+               H_Update(&ctx, &ctr, sizeof(ctr));
+               H_Final(&ctx, pwe_digest);
+
+               BN_bin2bn(pwe_digest, SHA256_DIGEST_LENGTH, rnd);
+
+               eap_pwd_kdf(pwe_digest, SHA256_DIGEST_LENGTH,
+                           (unsigned char *) "EAP-pwd Hunting and Pecking",
+                           os_strlen("EAP-pwd Hunting and Pecking"),
+                           prfbuf, primebitlen);
+
+               BN_bin2bn(prfbuf, primebytelen, x_candidate);
+               if (BN_ucmp(x_candidate, grp->prime) >= 0)
+                       continue;
+
+               wpa_hexdump(MSG_DEBUG, "EAP-pwd: x_candidate",
+                           prfbuf, primebytelen);
+
+               /*
+                * need to unambiguously identify the solution, if there is
+                * one...
+                */
+               if (BN_is_odd(rnd))
+                       is_odd = 1;
+               else
+                       is_odd = 0;
+
+               /*
+                * solve the quadratic equation, if it's not solvable then we
+                * don't have a point
+                */
+               if (!EC_POINT_set_compressed_coordinates_GFp(grp->group,
+                                                            grp->pwe,
+                                                            x_candidate,
+                                                            is_odd, NULL))
+                       continue;
+               /*
+                * If there's a solution to the equation then the point must be
+                * on the curve so why check again explicitly? OpenSSL code
+                * says this is required by X9.62. We're not X9.62 but it can't
+                * hurt just to be sure.
+                */
+               if (!EC_POINT_is_on_curve(grp->group, grp->pwe, NULL)) {
+                       wpa_printf(MSG_INFO, "EAP-pwd: point is not on curve");
+                       continue;
+               }
+
+               if (BN_cmp(cofactor, BN_value_one())) {
+                       /* make sure the point is not in a small sub-group */
+                       if (!EC_POINT_mul(grp->group, grp->pwe, NULL, grp->pwe,
+                                         cofactor, NULL)) {
+                               wpa_printf(MSG_INFO, "EAP-pwd: cannot "
+                                          "multiply generator by order");
+                               continue;
+                       }
+                       if (EC_POINT_is_at_infinity(grp->group, grp->pwe)) {
+                               wpa_printf(MSG_INFO, "EAP-pwd: point is at "
+                                          "infinity");
+                               continue;
+                       }
+               }
+               /* if we got here then we have a new generator. */
+               break;
+       }
+       wpa_printf(MSG_DEBUG, "EAP-pwd: found a PWE in %d tries", ctr);
+       grp->group_num = num;
+       if (0) {
+ fail:
+               EC_POINT_free(grp->pwe);
+               BN_free(grp->order);
+               BN_free(grp->prime);
+               free(grp);
+               grp = NULL;
+               ret = 1;
+       }
+       /* cleanliness and order.... */
+       BN_free(cofactor);
+       BN_free(x_candidate);
+       BN_free(rnd);
+       free(prfbuf);
+
+       return ret;
+}
+
+
+int compute_keys(EAP_PWD_group *grp, BN_CTX *bnctx, BIGNUM *k,
+                EC_POINT *server_element, EC_POINT *peer_element,
+                BIGNUM *server_scalar, BIGNUM *peer_scalar, u32 *ciphersuite,
+                u8 *msk, u8 *emsk)
+{
+       BIGNUM *scalar_sum, *x;
+       EC_POINT *element_sum;
+       HMAC_CTX ctx;
+       u8 mk[SHA256_DIGEST_LENGTH], *cruft;
+       u8 session_id[SHA256_DIGEST_LENGTH + 1];
+       u8 msk_emsk[EAP_MSK_LEN + EAP_EMSK_LEN];
+       int ret = -1;
+
+       if (((cruft = os_malloc(BN_num_bytes(grp->prime))) == NULL) ||
+           ((x = BN_new()) == NULL) ||
+           ((scalar_sum = BN_new()) == NULL) ||
+           ((element_sum = EC_POINT_new(grp->group)) == NULL))
+               return -1;
+
+       /*
+        * first compute the session-id = TypeCode | H(ciphersuite | scal_p |
+        *      scal_s)
+        */
+       session_id[0] = EAP_TYPE_PWD;
+       H_Init(&ctx);
+       H_Update(&ctx, (u8 *)ciphersuite, sizeof(u32));
+       BN_bn2bin(peer_scalar, cruft);
+       H_Update(&ctx, cruft, BN_num_bytes(grp->order));
+       BN_bn2bin(server_scalar, cruft);
+       H_Update(&ctx, cruft, BN_num_bytes(grp->order));
+       H_Final(&ctx, &session_id[1]);
+
+       /*
+        * then compute MK = H(k | F(elem_p + elem_s) |
+        *                     (scal_p + scal_s) mod r)
+        */
+       H_Init(&ctx);
+
+       /* k */
+       os_memset(cruft, 0, BN_num_bytes(grp->prime));
+       BN_bn2bin(k, cruft);
+       H_Update(&ctx, cruft, BN_num_bytes(grp->prime));
+
+       /* x = F(elem_p + elem_s) */
+       if ((!EC_POINT_add(grp->group, element_sum, server_element,
+                          peer_element, bnctx)) ||
+           (!EC_POINT_get_affine_coordinates_GFp(grp->group, element_sum, x,
+                                                 NULL, bnctx)))
+               goto fail;
+
+       os_memset(cruft, 0, BN_num_bytes(grp->prime));
+       BN_bn2bin(x, cruft);
+       H_Update(&ctx, cruft, BN_num_bytes(grp->prime));
+
+       /* (scal_p + scal_s) mod r */
+       BN_add(scalar_sum, server_scalar, peer_scalar);
+       BN_mod(scalar_sum, scalar_sum, grp->order, bnctx);
+       os_memset(cruft, 0, BN_num_bytes(grp->prime));
+       BN_bn2bin(scalar_sum, cruft);
+       H_Update(&ctx, cruft, BN_num_bytes(grp->order));
+       H_Final(&ctx, mk);
+
+       /* stretch the mk with the session-id to get MSK | EMSK */
+       eap_pwd_kdf(mk, SHA256_DIGEST_LENGTH,
+                   session_id, SHA256_DIGEST_LENGTH+1,
+                   msk_emsk, (EAP_MSK_LEN + EAP_EMSK_LEN) * 8);
+
+       os_memcpy(msk, msk_emsk, EAP_MSK_LEN);
+       os_memcpy(emsk, msk_emsk + EAP_MSK_LEN, EAP_EMSK_LEN);
+
+       ret = 1;
+
+fail:
+       BN_free(x);
+       BN_free(scalar_sum);
+       EC_POINT_free(element_sum);
+       os_free(cruft);
+
+       return ret;
+}
diff --git a/src/eap_common/eap_pwd_common.h b/src/eap_common/eap_pwd_common.h
new file mode 100644 (file)
index 0000000..7389894
--- /dev/null
@@ -0,0 +1,79 @@
+/*
+ * EAP server/peer: EAP-pwd shared definitions
+ * Copyright (c) 2009, Dan Harkins <dharkins@lounge.org>
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the BSD license.
+ *
+ * Alternatively, this software may be distributed under the terms of the
+ * GNU General Public License version 2 as published by the Free Software
+ * Foundation.
+ *
+ * See README and COPYING for more details.
+ */
+
+#ifndef EAP_PWD_COMMON_H
+#define EAP_PWD_COMMON_H
+
+#include <openssl/bn.h>
+#include <openssl/sha.h>
+#include <openssl/ec.h>
+#include <openssl/evp.h>
+#include <openssl/hmac.h>
+
+/*
+ * definition of a finite cyclic group
+ * TODO: support one based on a prime field
+ */
+typedef struct group_definition_ {
+       u16 group_num;
+       EC_GROUP *group;
+       EC_POINT *pwe;
+       BIGNUM *order;
+       BIGNUM *prime;
+} EAP_PWD_group;
+
+/*
+ * EAP-pwd header, included on all payloads
+ */
+struct eap_pwd_hdr {
+       u8 l_bit:1;
+       u8 m_bit:1;
+       u8 exch:6;
+       u8 total_length[0];         /* included when l_bit is set */
+} STRUCT_PACKED;
+
+#define EAP_PWD_OPCODE_ID_EXCH          1
+#define EAP_PWD_OPCODE_COMMIT_EXCH      2
+#define EAP_PWD_OPCODE_CONFIRM_EXCH     3
+#define EAP_PWD_GET_LENGTH_BIT(x)       ((x)->lm_exch & 0x80)
+#define EAP_PWD_SET_LENGTH_BIT(x)       ((x)->lm_exch |= 0x80)
+#define EAP_PWD_GET_MORE_BIT(x)         ((x)->lm_exch & 0x40)
+#define EAP_PWD_SET_MORE_BIT(x)         ((x)->lm_exch |= 0x40)
+#define EAP_PWD_GET_EXCHANGE(x)         ((x)->lm_exch & 0x3f)
+#define EAP_PWD_SET_EXCHANGE(x,y)       ((x)->lm_exch |= (y))
+
+/* EAP-pwd-ID payload */
+struct eap_pwd_id {
+       be16 group_num;
+       u8 random_function;
+#define EAP_PWD_DEFAULT_RAND_FUNC       1
+       u8 prf;
+#define EAP_PWD_DEFAULT_PRF             1
+       u8 token[4];
+       u8 prep;
+#define EAP_PWD_PREP_NONE               0
+#define EAP_PWD_PREP_MS                 1
+       u8 identity[0];     /* length inferred from payload */
+} STRUCT_PACKED;
+
+/* common routines */
+int compute_password_element(EAP_PWD_group *, u16, u8 *, int, u8 *, int, u8 *,
+                            int, u8 *);
+int compute_keys(EAP_PWD_group *, BN_CTX *, BIGNUM *, EC_POINT *, EC_POINT *,
+                 BIGNUM *, BIGNUM *, u32 *, u8 *, u8 *);
+void H_Init(HMAC_CTX *);
+void H_Update(HMAC_CTX *, const u8 *, int);
+void H_Final(HMAC_CTX *, u8 *);
+
+#endif  /* EAP_PWD_COMMON_H */
index 384c61b..4330b57 100644 (file)
@@ -109,5 +109,6 @@ int eap_peer_wsc_register(void);
 int eap_peer_ikev2_register(void);
 int eap_peer_vendor_test_register(void);
 int eap_peer_tnc_register(void);
+int eap_peer_pwd_register(void);
 
 #endif /* EAP_METHODS_H */
diff --git a/src/eap_peer/eap_pwd.c b/src/eap_peer/eap_pwd.c
new file mode 100644 (file)
index 0000000..8d21b92
--- /dev/null
@@ -0,0 +1,730 @@
+/*
+ * EAP peer method: EAP-pwd (RFC 5931)
+ * Copyright (c) 2010, Dan Harkins <dharkins@lounge.org>
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the BSD license.
+ *
+ * Alternatively, this software may be distributed under the terms of the
+ * GNU General Public License version 2 as published by the Free Software
+ * Foundation.
+ *
+ * See README and COPYING for more details.
+ */
+
+#include "includes.h"
+
+#include "common.h"
+#include "eap_peer/eap_i.h"
+#include "eap_common/eap_pwd_common.h"
+
+
+struct eap_pwd_data {
+       enum {
+               PWD_ID_Req, PWD_Commit_Req, PWD_Confirm_Req, SUCCESS, FAILURE
+       } state;
+       u8 *id_peer;
+       size_t id_peer_len;
+       u8 *id_server;
+       size_t id_server_len;
+       u8 *password;
+       size_t password_len;
+       u16 group_num;
+       EAP_PWD_group *grp;
+
+       BIGNUM *k;
+       BIGNUM *private_value;
+       BIGNUM *server_scalar;
+       BIGNUM *my_scalar;
+       EC_POINT *my_element;
+       EC_POINT *server_element;
+
+       u8 msk[EAP_MSK_LEN];
+       u8 emsk[EAP_EMSK_LEN];
+};
+
+static BN_CTX *bnctx;
+
+
+#ifndef CONFIG_NO_STDOUT_DEBUG
+static const char * eap_pwd_state_txt(int state)
+{
+       switch (state) {
+        case PWD_ID_Req:
+               return "PWD-ID-Req";
+        case PWD_Commit_Req:
+               return "PWD-Commit-Req";
+        case PWD_Confirm_Req:
+               return "PWD-Confirm-Req";
+        case SUCCESS:
+               return "SUCCESS";
+        case FAILURE:
+               return "FAILURE";
+        default:
+               return "PWD-UNK";
+       }
+}
+#endif  /* CONFIG_NO_STDOUT_DEBUG */
+
+
+static void eap_pwd_state(struct eap_pwd_data *data, int state)
+{
+       wpa_printf(MSG_INFO, "EAP-PWD: %s -> %s",
+                  eap_pwd_state_txt(data->state), eap_pwd_state_txt(state));
+       data->state = state;
+}
+
+
+static void * eap_pwd_init(struct eap_sm *sm)
+{
+       struct eap_pwd_data *data;
+       const u8 *identity, *password;
+       size_t identity_len, password_len;
+
+       password = eap_get_config_password(sm, &password_len);
+       if (password == NULL) {
+               wpa_printf(MSG_INFO, "EAP-PWD: No password configured!");
+               return NULL;
+       }
+
+       identity = eap_get_config_identity(sm, &identity_len);
+       if (identity == NULL) {
+               wpa_printf(MSG_INFO, "EAP-PWD: No identity configured!");
+               return NULL;
+       }
+
+       if ((bnctx = BN_CTX_new()) == NULL) {
+               wpa_printf(MSG_INFO, "EAP-PWD: bn context allocation fail");
+               return NULL;
+       }
+
+       if ((data = os_zalloc(sizeof(*data))) == NULL) {
+               wpa_printf(MSG_INFO, "EAP-PWD: memory allocation data fail");
+               return NULL;
+       }
+
+       if ((data->id_peer = os_malloc(identity_len)) == NULL) {
+               wpa_printf(MSG_INFO, "EAP-PWD: memory allocation id fail");
+               os_free(data);
+               return NULL;
+       }
+
+       os_memcpy(data->id_peer, identity, identity_len);
+       data->id_peer_len = identity_len;
+
+       if ((data->password = os_malloc(password_len)) == NULL) {
+               wpa_printf(MSG_INFO, "EAP-PWD: memory allocation psk fail");
+               os_free(data->id_peer);
+               os_free(data);
+               return NULL;
+       }
+       os_memcpy(data->password, password, password_len);
+       data->password_len = password_len;
+
+       data->state = PWD_ID_Req;
+
+       return data;
+}
+
+
+static void eap_pwd_deinit(struct eap_sm *sm, void *priv)
+{
+       struct eap_pwd_data *data = priv;
+
+       BN_free(data->private_value);
+       BN_free(data->server_scalar);
+       BN_free(data->my_scalar);
+       BN_free(data->k);
+       BN_CTX_free(bnctx);
+       EC_POINT_free(data->my_element);
+       EC_POINT_free(data->server_element);
+       os_free(data->id_peer);
+       os_free(data->password);
+       os_free(data->grp);
+       os_free(data);
+}
+
+
+static u8 * eap_pwd_getkey(struct eap_sm *sm, void *priv, size_t *len)
+{
+       struct eap_pwd_data *data = priv;
+       u8 *key;
+
+       if (data->state != SUCCESS)
+               return NULL;
+
+       key = os_malloc(EAP_MSK_LEN);
+       if (key == NULL)
+               return NULL;
+
+       os_memcpy(key, data->msk, EAP_MSK_LEN);
+       *len = EAP_MSK_LEN;
+
+       return key;
+}
+
+
+static struct wpabuf *
+eap_pwd_perform_id_exchange(struct eap_sm *sm, struct eap_pwd_data *data,
+                           struct eap_method_ret *ret,
+                           const struct wpabuf *reqData,
+                           const u8 *payload, size_t payload_len)
+{
+       struct eap_pwd_id *id;
+       struct wpabuf *resp;
+
+       if (data->state != PWD_ID_Req) {
+               ret->ignore = TRUE;
+               return NULL;
+       }
+
+       if (payload_len < sizeof(struct eap_pwd_id)) {
+               ret->ignore = TRUE;
+               return NULL;
+       }
+
+       id = (struct eap_pwd_id *) payload;
+       data->group_num = be_to_host16(id->group_num);
+       if ((id->random_function != EAP_PWD_DEFAULT_RAND_FUNC) ||
+           (id->prf != EAP_PWD_DEFAULT_PRF)) {
+               ret->ignore = TRUE;
+               return NULL;
+       }
+
+       wpa_printf(MSG_DEBUG, "EAP-PWD (peer): server said group %d",
+                  data->group_num);
+
+       data->id_server = os_malloc(payload_len - sizeof(struct eap_pwd_id));
+       if (data->id_server == NULL) {
+               wpa_printf(MSG_INFO, "EAP-PWD: memory allocation id fail");
+               return NULL;
+       }
+       data->id_server_len = payload_len - sizeof(struct eap_pwd_id);
+       os_memcpy(data->id_server, id->identity, data->id_server_len);
+       wpa_hexdump_ascii(MSG_INFO, "EAP-PWD (peer): server sent id of",
+                         data->id_server, data->id_server_len);
+
+       if ((data->grp = (EAP_PWD_group *) os_malloc(sizeof(EAP_PWD_group))) ==
+           NULL) {
+               wpa_printf(MSG_INFO, "EAP-PWD: failed to allocate memory for "
+                          "group");
+               return NULL;
+       }
+
+       /* compute PWE */
+       if (compute_password_element(data->grp, data->group_num,
+                                    data->password, data->password_len,
+                                    data->id_server, data->id_server_len,
+                                    data->id_peer, data->id_peer_len,
+                                    id->token)) {
+               wpa_printf(MSG_INFO, "EAP-PWD (peer): unable to compute PWE");
+               return NULL;
+       }
+
+       wpa_printf(MSG_INFO, "EAP-PWD (peer): computed %d bit PWE...",
+                  BN_num_bits(data->grp->prime));
+
+       resp = eap_msg_alloc(EAP_VENDOR_IETF, EAP_TYPE_PWD,
+                            1 + sizeof(struct eap_pwd_id) + data->id_peer_len,
+                            EAP_CODE_RESPONSE, eap_get_id(reqData));
+       if (resp == NULL)
+               return NULL;
+
+       wpabuf_put_u8(resp, EAP_PWD_OPCODE_ID_EXCH);
+       wpabuf_put_be16(resp, data->group_num);
+       wpabuf_put_u8(resp, EAP_PWD_DEFAULT_RAND_FUNC);
+       wpabuf_put_u8(resp, EAP_PWD_DEFAULT_PRF);
+       wpabuf_put_data(resp, id->token, sizeof(id->token));
+       wpabuf_put_u8(resp, EAP_PWD_PREP_NONE);
+       wpabuf_put_data(resp, data->id_peer, data->id_peer_len);
+
+       eap_pwd_state(data, PWD_Commit_Req);
+
+       return resp;
+}
+
+
+static struct wpabuf *
+eap_pwd_perform_commit_exchange(struct eap_sm *sm, struct eap_pwd_data *data,
+                               struct eap_method_ret *ret,
+                               const struct wpabuf *reqData,
+                               const u8 *payload, size_t payload_len)
+{
+       struct wpabuf *resp = NULL;
+       EC_POINT *K = NULL, *point = NULL;
+       BIGNUM *mask = NULL, *x = NULL, *y = NULL, *cofactor = NULL;
+       u16 offset;
+       u8 *ptr, *scalar = NULL, *element = NULL;
+
+       if (((data->private_value = BN_new()) == NULL) ||
+           ((data->my_element = EC_POINT_new(data->grp->group)) == NULL) ||
+           ((cofactor = BN_new()) == NULL) ||
+           ((data->my_scalar = BN_new()) == NULL) ||
+           ((mask = BN_new()) == NULL)) {
+               wpa_printf(MSG_INFO, "EAP-PWD (peer): scalar allocation fail");
+               goto fin;
+       }
+
+       if (!EC_GROUP_get_cofactor(data->grp->group, cofactor, NULL)) {
+               wpa_printf(MSG_INFO, "EAP-pwd (peer): unable to get cofactor "
+                          "for curve");
+               goto fin;
+       }
+
+       BN_rand_range(data->private_value, data->grp->order);
+       BN_rand_range(mask, data->grp->order);
+       BN_add(data->my_scalar, data->private_value, mask);
+       BN_mod(data->my_scalar, data->my_scalar, data->grp->order, bnctx);
+
+       if (!EC_POINT_mul(data->grp->group, data->my_element, NULL,
+                         data->grp->pwe, mask, bnctx)) {
+               wpa_printf(MSG_INFO, "EAP-PWD (peer): element allocation "
+                          "fail");
+               eap_pwd_state(data, FAILURE);
+               goto fin;
+       }
+
+       if (!EC_POINT_invert(data->grp->group, data->my_element, bnctx)) {
+               wpa_printf(MSG_INFO, "EAP-PWD (peer): element inversion fail");
+               goto fin;
+       }
+       BN_free(mask);
+
+       if (((x = BN_new()) == NULL) ||
+           ((y = BN_new()) == NULL)) {
+               wpa_printf(MSG_INFO, "EAP-PWD (peer): point allocation fail");
+               goto fin;
+       }
+
+       /* process the request */
+       if (((data->server_scalar = BN_new()) == NULL) ||
+           ((data->k = BN_new()) == NULL) ||
+           ((K = EC_POINT_new(data->grp->group)) == NULL) ||
+           ((point = EC_POINT_new(data->grp->group)) == NULL) ||
+           ((data->server_element = EC_POINT_new(data->grp->group)) == NULL))
+       {
+               wpa_printf(MSG_INFO, "EAP-PWD (peer): peer data allocation "
+                          "fail");
+               goto fin;
+       }
+
+       /* element, x then y, followed by scalar */
+       ptr = (u8 *) payload;
+       BN_bin2bn(ptr, BN_num_bytes(data->grp->prime), x);
+       ptr += BN_num_bytes(data->grp->prime);
+       BN_bin2bn(ptr, BN_num_bytes(data->grp->prime), y);
+       ptr += BN_num_bytes(data->grp->prime);
+       BN_bin2bn(ptr, BN_num_bytes(data->grp->order), data->server_scalar);
+       if (!EC_POINT_set_affine_coordinates_GFp(data->grp->group,
+                                                data->server_element, x, y,
+                                                bnctx)) {
+               wpa_printf(MSG_INFO, "EAP-PWD (peer): setting peer element "
+                          "fail");
+               goto fin;
+       }
+
+       /* check to ensure server's element is not in a small sub-group */
+       if (BN_cmp(cofactor, BN_value_one())) {
+               if (!EC_POINT_mul(data->grp->group, point, NULL,
+                                 data->server_element, cofactor, NULL)) {
+                       wpa_printf(MSG_INFO, "EAP-PWD (peer): cannot multiply "
+                                  "server element by order!\n");
+                       goto fin;
+               }
+               if (EC_POINT_is_at_infinity(data->grp->group, point)) {
+                       wpa_printf(MSG_INFO, "EAP-PWD (peer): server element "
+                                  "is at infinity!\n");
+                       goto fin;
+               }
+       }
+
+       /* compute the shared key, k */
+       if ((!EC_POINT_mul(data->grp->group, K, NULL, data->grp->pwe,
+                          data->server_scalar, bnctx)) ||
+           (!EC_POINT_add(data->grp->group, K, K, data->server_element,
+                          bnctx)) ||
+           (!EC_POINT_mul(data->grp->group, K, NULL, K, data->private_value,
+                          bnctx))) {
+               wpa_printf(MSG_INFO, "EAP-PWD (peer): computing shared key "
+                          "fail");
+               goto fin;
+       }
+
+       /* ensure that the shared key isn't in a small sub-group */
+       if (BN_cmp(cofactor, BN_value_one())) {
+               if (!EC_POINT_mul(data->grp->group, K, NULL, K, cofactor,
+                                 NULL)) {
+                       wpa_printf(MSG_INFO, "EAP-PWD (peer): cannot multiply "
+                                  "shared key point by order");
+                       goto fin;
+               }
+       }
+
+       /*
+        * This check is strictly speaking just for the case above where
+        * co-factor > 1 but it was suggested that even though this is probably
+        * never going to happen it is a simple and safe check "just to be
+        * sure" so let's be safe.
+        */
+       if (EC_POINT_is_at_infinity(data->grp->group, K)) {
+               wpa_printf(MSG_INFO, "EAP-PWD (peer): shared key point is at "
+                          "infinity!\n");
+               goto fin;
+       }
+
+       if (!EC_POINT_get_affine_coordinates_GFp(data->grp->group, K, data->k,
+                                                NULL, bnctx)) {
+               wpa_printf(MSG_INFO, "EAP-PWD (peer): unable to extract "
+                          "shared secret from point");
+               goto fin;
+       }
+
+       /* now do the response */
+       if (!EC_POINT_get_affine_coordinates_GFp(data->grp->group,
+                                                data->my_element, x, y,
+                                                bnctx)) {
+               wpa_printf(MSG_INFO, "EAP-PWD (peer): point assignment fail");
+               goto fin;
+       }
+
+       if (((scalar = os_malloc(BN_num_bytes(data->grp->order))) == NULL) ||
+           ((element = os_malloc(BN_num_bytes(data->grp->prime) * 2)) ==
+            NULL)) {
+               wpa_printf(MSG_INFO, "EAP-PWD (peer): data allocation fail");
+               goto fin;
+       }
+
+       /*
+        * bignums occupy as little memory as possible so one that is
+        * sufficiently smaller than the prime or order might need pre-pending
+        * with zeros.
+        */
+       os_memset(scalar, 0, BN_num_bytes(data->grp->order));
+       os_memset(element, 0, BN_num_bytes(data->grp->prime) * 2);
+       offset = BN_num_bytes(data->grp->order) -
+               BN_num_bytes(data->my_scalar);
+       BN_bn2bin(data->my_scalar, scalar + offset);
+
+       offset = BN_num_bytes(data->grp->prime) - BN_num_bytes(x);
+       BN_bn2bin(x, element + offset);
+       offset = BN_num_bytes(data->grp->prime) - BN_num_bytes(y);
+       BN_bn2bin(y, element + BN_num_bytes(data->grp->prime) + offset);
+
+       resp = eap_msg_alloc(EAP_VENDOR_IETF, EAP_TYPE_PWD,
+                            sizeof(struct eap_pwd_hdr) +
+                            BN_num_bytes(data->grp->order) +
+                            (2 * BN_num_bytes(data->grp->prime)),
+                            EAP_CODE_RESPONSE, eap_get_id(reqData));
+       if (resp == NULL)
+               goto fin;
+
+       wpabuf_put_u8(resp, EAP_PWD_OPCODE_COMMIT_EXCH);
+
+       /* we send the element as (x,y) follwed by the scalar */
+       wpabuf_put_data(resp, element, (2 * BN_num_bytes(data->grp->prime)));
+       wpabuf_put_data(resp, scalar, BN_num_bytes(data->grp->order));
+
+fin:
+       os_free(scalar);
+       os_free(element);
+       BN_free(x);
+       BN_free(y);
+       BN_free(cofactor);
+       EC_POINT_free(K);
+       EC_POINT_free(point);
+       if (resp == NULL)
+               eap_pwd_state(data, FAILURE);
+       else
+               eap_pwd_state(data, PWD_Confirm_Req);
+
+       return resp;
+}
+
+
+static struct wpabuf *
+eap_pwd_perform_confirm_exchange(struct eap_sm *sm, struct eap_pwd_data *data,
+                                struct eap_method_ret *ret,
+                                const struct wpabuf *reqData,
+                                const u8 *payload, size_t payload_len)
+{
+       struct wpabuf *resp = NULL;
+       BIGNUM *x = NULL, *y = NULL;
+       HMAC_CTX ctx;
+       u32 cs;
+       u8 conf[SHA256_DIGEST_LENGTH], *cruft = NULL, *ptr;
+
+       /*
+        * first build up the ciphersuite which is group | random_function |
+        *      prf
+        */
+       ptr = (u8 *) &cs;
+       os_memcpy(ptr, &data->group_num, sizeof(u16));
+       ptr += sizeof(u16);
+       *ptr = EAP_PWD_DEFAULT_RAND_FUNC;
+       ptr += sizeof(u8);
+       *ptr = EAP_PWD_DEFAULT_PRF;
+
+       /* each component of the cruft will be at most as big as the prime */
+       if (((cruft = os_malloc(BN_num_bytes(data->grp->prime))) == NULL) ||
+           ((x = BN_new()) == NULL) || ((y = BN_new()) == NULL)) {
+               wpa_printf(MSG_INFO, "EAP-PWD (server): debug allocation "
+                          "fail");
+               goto fin;
+       }
+
+       /*
+        * server's commit is H(k | server_element | server_scalar |
+        *                      peer_element | peer_scalar | ciphersuite)
+        */
+       H_Init(&ctx);
+
+       /*
+        * zero the memory each time because this is mod prime math and some
+        * value may start with a few zeros and the previous one did not.
+        */
+       os_memset(cruft, 0, BN_num_bytes(data->grp->prime));
+       BN_bn2bin(data->k, cruft);
+       H_Update(&ctx, cruft, BN_num_bytes(data->grp->prime));
+
+       /* server element: x, y */
+       if (!EC_POINT_get_affine_coordinates_GFp(data->grp->group,
+                                                data->server_element, x, y,
+                                                bnctx)) {
+               wpa_printf(MSG_INFO, "EAP-PWD (server): confirm point "
+                          "assignment fail");
+               goto fin;
+       }
+       os_memset(cruft, 0, BN_num_bytes(data->grp->prime));
+       BN_bn2bin(x, cruft);
+       H_Update(&ctx, cruft, BN_num_bytes(data->grp->prime));
+       os_memset(cruft, 0, BN_num_bytes(data->grp->prime));
+       BN_bn2bin(y, cruft);
+       H_Update(&ctx, cruft, BN_num_bytes(data->grp->prime));
+
+       /* server scalar */
+       os_memset(cruft, 0, BN_num_bytes(data->grp->prime));
+       BN_bn2bin(data->server_scalar, cruft);
+       H_Update(&ctx, cruft, BN_num_bytes(data->grp->order));
+
+       /* my element: x, y */
+       if (!EC_POINT_get_affine_coordinates_GFp(data->grp->group,
+                                                data->my_element, x, y,
+                                                bnctx)) {
+               wpa_printf(MSG_INFO, "EAP-PWD (server): confirm point "
+                          "assignment fail");
+               goto fin;
+       }
+
+       os_memset(cruft, 0, BN_num_bytes(data->grp->prime));
+       BN_bn2bin(x, cruft);
+       H_Update(&ctx, cruft, BN_num_bytes(data->grp->prime));
+       os_memset(cruft, 0, BN_num_bytes(data->grp->prime));
+       BN_bn2bin(y, cruft);
+       H_Update(&ctx, cruft, BN_num_bytes(data->grp->prime));
+
+       /* my scalar */
+       os_memset(cruft, 0, BN_num_bytes(data->grp->prime));
+       BN_bn2bin(data->my_scalar, cruft);
+       H_Update(&ctx, cruft, BN_num_bytes(data->grp->order));
+
+       /* the ciphersuite */
+       H_Update(&ctx, (u8 *) &cs, sizeof(u32));
+
+       /* random function fin */
+       H_Final(&ctx, conf);
+
+       ptr = (u8 *) payload;
+       if (os_memcmp(conf, ptr, SHA256_DIGEST_LENGTH)) {
+               wpa_printf(MSG_INFO, "EAP-PWD (peer): confirm did not verify");
+               goto fin;
+       }
+
+       wpa_printf(MSG_DEBUG, "EAP-pwd (peer): confirm verified");
+
+       /*
+        * compute confirm:
+        *  H(k | peer_element | peer_scalar | server_element | server_scalar |
+        *    ciphersuite)
+        */
+       H_Init(&ctx);
+
+       /* k */
+       os_memset(cruft, 0, BN_num_bytes(data->grp->prime));
+       BN_bn2bin(data->k, cruft);
+       H_Update(&ctx, cruft, BN_num_bytes(data->grp->prime));
+
+       /* my element */
+       if (!EC_POINT_get_affine_coordinates_GFp(data->grp->group,
+                                                data->my_element, x, y,
+                                                bnctx)) {
+               wpa_printf(MSG_INFO, "EAP-PWD (peer): confirm point "
+                          "assignment fail");
+               goto fin;
+       }
+       os_memset(cruft, 0, BN_num_bytes(data->grp->prime));
+       BN_bn2bin(x, cruft);
+       H_Update(&ctx, cruft, BN_num_bytes(data->grp->prime));
+       os_memset(cruft, 0, BN_num_bytes(data->grp->prime));
+       BN_bn2bin(y, cruft);
+       H_Update(&ctx, cruft, BN_num_bytes(data->grp->prime));
+
+       /* my scalar */
+       os_memset(cruft, 0, BN_num_bytes(data->grp->prime));
+       BN_bn2bin(data->my_scalar, cruft);
+       H_Update(&ctx, cruft, BN_num_bytes(data->grp->order));
+
+       /* server element: x, y */
+       if (!EC_POINT_get_affine_coordinates_GFp(data->grp->group,
+                                                data->server_element, x, y,
+                                                bnctx)) {
+               wpa_printf(MSG_INFO, "EAP-PWD (peer): confirm point "
+                          "assignment fail");
+               goto fin;
+       }
+       os_memset(cruft, 0, BN_num_bytes(data->grp->prime));
+       BN_bn2bin(x, cruft);
+       H_Update(&ctx, cruft, BN_num_bytes(data->grp->prime));
+       os_memset(cruft, 0, BN_num_bytes(data->grp->prime));
+       BN_bn2bin(y, cruft);
+       H_Update(&ctx, cruft, BN_num_bytes(data->grp->prime));
+
+       /* server scalar */
+       os_memset(cruft, 0, BN_num_bytes(data->grp->prime));
+       BN_bn2bin(data->server_scalar, cruft);
+       H_Update(&ctx, cruft, BN_num_bytes(data->grp->order));
+
+       /* the ciphersuite */
+       H_Update(&ctx, (u8 *) &cs, sizeof(u32));
+
+       /* all done */
+       H_Final(&ctx, conf);
+
+       resp = eap_msg_alloc(EAP_VENDOR_IETF, EAP_TYPE_PWD,
+                            sizeof(struct eap_pwd_hdr) + SHA256_DIGEST_LENGTH,
+                            EAP_CODE_RESPONSE, eap_get_id(reqData));
+       if (resp == NULL)
+               goto fin;
+
+       wpabuf_put_u8(resp, EAP_PWD_OPCODE_CONFIRM_EXCH);
+       wpabuf_put_data(resp, conf, SHA256_DIGEST_LENGTH);
+
+       if (compute_keys(data->grp, bnctx, data->k, data->server_element,
+                        data->my_element, data->server_scalar,
+                        data->my_scalar, &cs, data->msk, data->emsk) < 0) {
+               wpa_printf(MSG_INFO, "EAP-PWD (peer): unable to compute MSK | "
+                          "EMSK");
+               goto fin;
+       }
+
+fin:
+       os_free(cruft);
+       BN_free(x);
+       BN_free(y);
+       ret->methodState = METHOD_DONE;
+       if (resp == NULL) {
+               ret->decision = DECISION_FAIL;
+               eap_pwd_state(data, FAILURE);
+       } else {
+               ret->decision = DECISION_UNCOND_SUCC;
+               eap_pwd_state(data, SUCCESS);
+       }
+
+       return resp;
+}
+
+
+static struct wpabuf *
+eap_pwd_process(struct eap_sm *sm, void *priv, struct eap_method_ret *ret,
+               const struct wpabuf *reqData)
+{
+       struct eap_pwd_data *data = priv;
+       struct wpabuf *resp = NULL;
+       const u8 *pos;
+       size_t len;
+       u8 exch;
+
+       pos = eap_hdr_validate(EAP_VENDOR_IETF, EAP_TYPE_PWD, reqData, &len);
+       if ((pos == NULL) || (len < 1)) {
+               ret->ignore = TRUE;
+               return NULL;
+       }
+
+       wpa_printf(MSG_INFO, "EAP-pwd: Received frame: opcode %d", *pos);
+
+       ret->ignore = FALSE;
+       ret->methodState = METHOD_MAY_CONT;
+       ret->decision = DECISION_FAIL;
+       ret->allowNotifications = FALSE;
+
+       exch = *pos & 0x3f;
+       switch (exch) {
+        case EAP_PWD_OPCODE_ID_EXCH:
+               resp = eap_pwd_perform_id_exchange(sm, data, ret, reqData,
+                                                  pos + 1, len - 1);
+               break;
+        case EAP_PWD_OPCODE_COMMIT_EXCH:
+               resp = eap_pwd_perform_commit_exchange(sm, data, ret, reqData,
+                                                      pos + 1, len - 1);
+               break;
+        case EAP_PWD_OPCODE_CONFIRM_EXCH:
+               resp = eap_pwd_perform_confirm_exchange(sm, data, ret, reqData,
+                                                       pos + 1, len - 1);
+               break;
+        default:
+               wpa_printf(MSG_INFO, "EAP-pwd: Ignoring message with unknown "
+                          "opcode %d", exch);
+               break;
+       }
+
+       return resp;
+}
+
+
+static Boolean eap_pwd_key_available(struct eap_sm *sm, void *priv)
+{
+       struct eap_pwd_data *data = priv;
+       return data->state == SUCCESS;
+}
+
+
+static u8 * eap_pwd_get_emsk(struct eap_sm *sm, void *priv, size_t *len)
+{
+       struct eap_pwd_data *data = priv;
+       u8 *key;
+
+       if (data->state != SUCCESS)
+               return NULL;
+
+       if ((key = os_malloc(EAP_EMSK_LEN)) == NULL)
+               return NULL;
+
+       os_memcpy(key, data->emsk, EAP_EMSK_LEN);
+       *len = EAP_EMSK_LEN;
+
+       return key;
+}
+
+
+int eap_peer_pwd_register(void)
+{
+       struct eap_method *eap;
+       int ret;
+
+       EVP_add_digest(EVP_sha256());
+       eap = eap_peer_method_alloc(EAP_PEER_METHOD_INTERFACE_VERSION,
+                                   EAP_VENDOR_IETF, EAP_TYPE_PWD, "PWD");
+       if (eap == NULL)
+               return -1;
+
+       eap->init = eap_pwd_init;
+       eap->deinit = eap_pwd_deinit;
+       eap->process = eap_pwd_process;
+       eap->isKeyAvailable = eap_pwd_key_available;
+       eap->getKey = eap_pwd_getkey;
+       eap->get_emsk = eap_pwd_get_emsk;
+
+       ret = eap_peer_method_register(eap);
+       if (ret)
+               eap_peer_method_free(eap);
+       return ret;
+}
index 8a34671..0c09923 100644 (file)
@@ -95,6 +95,7 @@ struct eap_config {
        void *eap_sim_db_priv;
        Boolean backend_auth;
        int eap_server;
+       u16 pwd_group;
        u8 *pac_opaque_encr_key;
        u8 *eap_fast_a_id;
        size_t eap_fast_a_id_len;
index 3b3e49c..daac746 100644 (file)
@@ -181,6 +181,7 @@ struct eap_sm {
        int pac_key_refresh_time;
        int eap_sim_aka_result_ind;
        int tnc;
+       u16 pwd_group;
        struct wps_context *wps;
        struct wpabuf *assoc_wps_ie;
        struct wpabuf *assoc_p2p_ie;
index 5d4d92c..4a5296e 100644 (file)
@@ -49,5 +49,6 @@ int eap_server_fast_register(void);
 int eap_server_wsc_register(void);
 int eap_server_ikev2_register(void);
 int eap_server_tnc_register(void);
+int eap_server_pwd_register(void);
 
 #endif /* EAP_SERVER_METHODS_H */
index 1d19251..5812b33 100644 (file)
@@ -1260,6 +1260,7 @@ struct eap_sm * eap_server_sm_init(void *eapol_ctx,
        if (conf->peer_addr)
                os_memcpy(sm->peer_addr, conf->peer_addr, ETH_ALEN);
        sm->fragment_size = conf->fragment_size;
+       sm->pwd_group = conf->pwd_group;
 
        wpa_printf(MSG_DEBUG, "EAP: Server state machine created");
 
diff --git a/src/eap_server/eap_server_pwd.c b/src/eap_server/eap_server_pwd.c
new file mode 100644 (file)
index 0000000..d1b89ea
--- /dev/null
@@ -0,0 +1,823 @@
+/*
+ * hostapd / EAP-pwd (RFC 5931) server
+ * Copyright (c) 2010, Dan Harkins <dharkins@lounge.org>
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the BSD license.
+ *
+ * Alternatively, this software may be distributed under the terms of the
+ * GNU General Public License version 2 as published by the Free Software
+ * Foundation.
+ *
+ * See README and COPYING for more details.
+ */
+
+#include "includes.h"
+
+#include "common.h"
+#include "eap_server/eap_i.h"
+#include "eap_common/eap_pwd_common.h"
+
+
+struct eap_pwd_data {
+       enum {
+               PWD_ID_Req, PWD_Commit_Req, PWD_Confirm_Req, SUCCESS, FAILURE
+       } state;
+       u8 *id_peer;
+       size_t id_peer_len;
+       u8 *id_server;
+       size_t id_server_len;
+       u8 *password;
+       size_t password_len;
+       u32 token;
+       u16 group_num;
+       EAP_PWD_group *grp;
+
+       BIGNUM *k;
+       BIGNUM *private_value;
+       BIGNUM *peer_scalar;
+       BIGNUM *my_scalar;
+       EC_POINT *my_element;
+       EC_POINT *peer_element;
+
+       u8 msk[EAP_MSK_LEN];
+       u8 emsk[EAP_EMSK_LEN];
+};
+
+static BN_CTX *bnctx;
+
+
+static const char * eap_pwd_state_txt(int state)
+{
+       switch (state) {
+        case PWD_ID_Req:
+               return "PWD-ID-Req";
+        case PWD_Commit_Req:
+               return "PWD-Commit-Req";
+        case PWD_Confirm_Req:
+               return "PWD-Confirm-Req";
+        case SUCCESS:
+               return "SUCCESS";
+        case FAILURE:
+               return "FAILURE";
+        default:
+               return "PWD-Unk";
+       }
+}
+
+
+static void eap_pwd_state(struct eap_pwd_data *data, int state)
+{
+       wpa_printf(MSG_DEBUG, "EAP-pwd: %s -> %s",
+                  eap_pwd_state_txt(data->state), eap_pwd_state_txt(state));
+       data->state = state;
+}
+
+
+static void * eap_pwd_init(struct eap_sm *sm)
+{
+       struct eap_pwd_data *data;
+
+       if (sm->user == NULL || sm->user->password == NULL ||
+           sm->user->password_len == 0) {
+               wpa_printf(MSG_INFO, "EAP-PWD (server): Password is not "
+                          "configured");
+               return NULL;
+       }
+
+       data = os_zalloc(sizeof(*data));
+       if (data == NULL)
+               return NULL;
+
+       data->group_num = sm->pwd_group;
+       wpa_printf(MSG_DEBUG, "EAP-pwd: Selected group number %d",
+                  data->group_num);
+       data->state = PWD_ID_Req;
+
+       data->id_server = (u8 *) os_strdup("server");
+       if (data->id_server)
+               data->id_server_len = os_strlen((char *)data->id_server);
+
+       data->password = os_malloc(sm->user->password_len);
+       if (data->password == NULL) {
+               wpa_printf(MSG_INFO, "EAP-PWD: Mmemory allocation password "
+                          "fail");
+               return NULL;
+       }
+       data->password_len = sm->user->password_len;
+       os_memcpy(data->password, sm->user->password, data->password_len);
+
+       bnctx = BN_CTX_new();
+       if (bnctx == NULL) {
+               wpa_printf(MSG_INFO, "EAP-PWD: bn context allocation fail");
+               return NULL;
+       }
+
+       return data;
+}
+
+
+static void eap_pwd_reset(struct eap_sm *sm, void *priv)
+{
+       struct eap_pwd_data *data = priv;
+
+       BN_free(data->private_value);
+       BN_free(data->peer_scalar);
+       BN_free(data->my_scalar);
+       BN_free(data->k);
+       BN_CTX_free(bnctx);
+       EC_POINT_free(data->my_element);
+       EC_POINT_free(data->peer_element);
+       os_free(data->id_peer);
+       os_free(data->id_server);
+       os_free(data->grp);
+       os_free(data);
+}
+
+
+static struct wpabuf *
+eap_pwd_build_id_req(struct eap_sm *sm, struct eap_pwd_data *data, u8 id)
+{
+       struct wpabuf *req;
+
+       wpa_printf(MSG_DEBUG, "EAP-pwd: ID/Request");
+       req = eap_msg_alloc(EAP_VENDOR_IETF, EAP_TYPE_PWD,
+                           sizeof(struct eap_pwd_hdr) +
+                           sizeof(struct eap_pwd_id) + data->id_server_len,
+                           EAP_CODE_REQUEST, id);
+       if (req == NULL) {
+               eap_pwd_state(data, FAILURE);
+               return NULL;
+       }
+
+       /* an lfsr is good enough to generate unpredictable tokens */
+       data->token = os_random();
+       wpabuf_put_u8(req, EAP_PWD_OPCODE_ID_EXCH);
+       wpabuf_put_be16(req, data->group_num);
+       wpabuf_put_u8(req, EAP_PWD_DEFAULT_RAND_FUNC);
+       wpabuf_put_u8(req, EAP_PWD_DEFAULT_PRF);
+       wpabuf_put_data(req, &data->token, sizeof(data->token));
+       wpabuf_put_u8(req, EAP_PWD_PREP_NONE);
+       wpabuf_put_data(req, data->id_server, data->id_server_len);
+
+       return req;
+}
+
+
+static struct wpabuf *
+eap_pwd_build_commit_req(struct eap_sm *sm, struct eap_pwd_data *data, u8 id)
+{
+       struct wpabuf *req = NULL;
+       BIGNUM *mask = NULL, *x = NULL, *y = NULL;
+       u8 *scalar = NULL, *element = NULL;
+       u16 offset;
+
+       wpa_printf(MSG_DEBUG, "EAP-pwd: Commit/Request");
+
+       if (((data->private_value = BN_new()) == NULL) ||
+           ((data->my_element = EC_POINT_new(data->grp->group)) == NULL) ||
+           ((data->my_scalar = BN_new()) == NULL) ||
+           ((mask = BN_new()) == NULL)) {
+               wpa_printf(MSG_INFO, "EAP-PWD (server): scalar allocation "
+                          "fail");
+               goto fin;
+       }
+
+       BN_rand_range(data->private_value, data->grp->order);
+       BN_rand_range(mask, data->grp->order);
+       BN_add(data->my_scalar, data->private_value, mask);
+       BN_mod(data->my_scalar, data->my_scalar, data->grp->order, bnctx);
+
+       if (!EC_POINT_mul(data->grp->group, data->my_element, NULL,
+                         data->grp->pwe, mask, bnctx)) {
+               wpa_printf(MSG_INFO, "EAP-PWD (server): element allocation "
+                          "fail");
+               eap_pwd_state(data, FAILURE);
+               goto fin;
+       }
+
+       if (!EC_POINT_invert(data->grp->group, data->my_element, bnctx)) {
+               wpa_printf(MSG_INFO, "EAP-PWD (server): element inversion "
+                          "fail");
+               goto fin;
+       }
+       BN_free(mask);
+
+       if (((x = BN_new()) == NULL) ||
+           ((y = BN_new()) == NULL)) {
+               wpa_printf(MSG_INFO, "EAP-PWD (server): point allocation "
+                          "fail");
+               goto fin;
+       }
+       if (!EC_POINT_get_affine_coordinates_GFp(data->grp->group,
+                                                data->my_element, x, y,
+                                                bnctx)) {
+               wpa_printf(MSG_INFO, "EAP-PWD (server): point assignment "
+                          "fail");
+               goto fin;
+       }
+
+       if (((scalar = os_malloc(BN_num_bytes(data->grp->order))) == NULL) ||
+           ((element = os_malloc(BN_num_bytes(data->grp->prime) * 2)) ==
+            NULL)) {
+               wpa_printf(MSG_INFO, "EAP-PWD (server): data allocation fail");
+               goto fin;
+       }
+
+       /*
+        * bignums occupy as little memory as possible so one that is
+        * sufficiently smaller than the prime or order might need pre-pending
+        * with zeros.
+        */
+       os_memset(scalar, 0, BN_num_bytes(data->grp->order));
+       os_memset(element, 0, BN_num_bytes(data->grp->prime) * 2);
+       offset = BN_num_bytes(data->grp->order) -
+               BN_num_bytes(data->my_scalar);
+       BN_bn2bin(data->my_scalar, scalar + offset);
+
+       offset = BN_num_bytes(data->grp->prime) - BN_num_bytes(x);
+       BN_bn2bin(x, element + offset);
+       offset = BN_num_bytes(data->grp->prime) - BN_num_bytes(y);
+       BN_bn2bin(y, element + BN_num_bytes(data->grp->prime) + offset);
+
+       req = eap_msg_alloc(EAP_VENDOR_IETF, EAP_TYPE_PWD,
+                           sizeof(struct eap_pwd_hdr) +
+                           (2 * BN_num_bytes(data->grp->prime)) +
+                           BN_num_bytes(data->grp->order),
+                           EAP_CODE_REQUEST, id);
+       if (req == NULL)
+               goto fin;
+       wpabuf_put_u8(req, EAP_PWD_OPCODE_COMMIT_EXCH);
+
+       /* We send the element as (x,y) followed by the scalar */
+       wpabuf_put_data(req, element, (2 * BN_num_bytes(data->grp->prime)));
+       wpabuf_put_data(req, scalar, BN_num_bytes(data->grp->order));
+
+fin:
+       os_free(scalar);
+       os_free(element);
+       BN_free(x);
+       BN_free(y);
+       if (req == NULL)
+               eap_pwd_state(data, FAILURE);
+
+       return req;
+}
+
+
+static struct wpabuf *
+eap_pwd_build_confirm_req(struct eap_sm *sm, struct eap_pwd_data *data, u8 id)
+{
+       struct wpabuf *req = NULL;
+       BIGNUM *x = NULL, *y = NULL;
+       HMAC_CTX ctx;
+       u8 conf[SHA256_DIGEST_LENGTH], *cruft = NULL, *ptr;
+
+       wpa_printf(MSG_DEBUG, "EAP-pwd: Confirm/Request");
+
+       /* Each component of the cruft will be at most as big as the prime */
+       if (((cruft = os_malloc(BN_num_bytes(data->grp->prime))) == NULL) ||
+           ((x = BN_new()) == NULL) || ((y = BN_new()) == NULL)) {
+               wpa_printf(MSG_INFO, "EAP-PWD (server): debug allocation "
+                          "fail");
+               goto fin;
+       }
+
+       /*
+        * commit is H(k | server_element | server_scalar | peer_element |
+        *             peer_scalar | ciphersuite)
+        */
+       H_Init(&ctx);
+
+       /*
+        * Zero the memory each time because this is mod prime math and some
+        * value may start with a few zeros and the previous one did not.
+        *
+        * First is k
+        */
+       os_memset(cruft, 0, BN_num_bytes(data->grp->prime));
+       BN_bn2bin(data->k, cruft);
+       H_Update(&ctx, cruft, BN_num_bytes(data->grp->prime));
+
+       /* server element: x, y */
+       if (!EC_POINT_get_affine_coordinates_GFp(data->grp->group,
+                                                data->my_element, x, y,
+                                                bnctx)) {
+               wpa_printf(MSG_INFO, "EAP-PWD (server): confirm point "
+                          "assignment fail");
+               goto fin;
+       }
+
+       os_memset(cruft, 0, BN_num_bytes(data->grp->prime));
+       BN_bn2bin(x, cruft);
+       H_Update(&ctx, cruft, BN_num_bytes(data->grp->prime));
+       os_memset(cruft, 0, BN_num_bytes(data->grp->prime));
+       BN_bn2bin(y, cruft);
+       H_Update(&ctx, cruft, BN_num_bytes(data->grp->prime));
+
+       /* server scalar */
+       os_memset(cruft, 0, BN_num_bytes(data->grp->prime));
+       BN_bn2bin(data->my_scalar, cruft);
+       H_Update(&ctx, cruft, BN_num_bytes(data->grp->order));
+
+       /* peer element: x, y */
+       if (!EC_POINT_get_affine_coordinates_GFp(data->grp->group,
+                                                data->peer_element, x, y,
+                                                bnctx)) {
+               wpa_printf(MSG_INFO, "EAP-PWD (server): confirm point "
+                          "assignment fail");
+               goto fin;
+       }
+
+       os_memset(cruft, 0, BN_num_bytes(data->grp->prime));
+       BN_bn2bin(x, cruft);
+       H_Update(&ctx, cruft, BN_num_bytes(data->grp->prime));
+       os_memset(cruft, 0, BN_num_bytes(data->grp->prime));
+       BN_bn2bin(y, cruft);
+       H_Update(&ctx, cruft, BN_num_bytes(data->grp->prime));
+
+       /* peer scalar */
+       os_memset(cruft, 0, BN_num_bytes(data->grp->prime));
+       BN_bn2bin(data->peer_scalar, cruft);
+       H_Update(&ctx, cruft, BN_num_bytes(data->grp->order));
+
+       /* ciphersuite */
+       os_memset(cruft, 0, BN_num_bytes(data->grp->prime));
+       ptr = cruft;
+       os_memcpy(ptr, &data->group_num, sizeof(u16));
+       ptr += sizeof(u16);
+       *ptr = EAP_PWD_DEFAULT_RAND_FUNC;
+       ptr += sizeof(u8);
+       *ptr = EAP_PWD_DEFAULT_PRF;
+       ptr += sizeof(u8);
+       H_Update(&ctx, cruft, ptr-cruft);
+
+       /* all done with the random function */
+       H_Final(&ctx, conf);
+
+       req = eap_msg_alloc(EAP_VENDOR_IETF, EAP_TYPE_PWD,
+                           sizeof(struct eap_pwd_hdr) + SHA256_DIGEST_LENGTH,
+                           EAP_CODE_REQUEST, id);
+       if (req == NULL)
+               goto fin;
+
+       wpabuf_put_u8(req, EAP_PWD_OPCODE_CONFIRM_EXCH);
+       wpabuf_put_data(req, conf, SHA256_DIGEST_LENGTH);
+
+fin:
+       os_free(cruft);
+       BN_free(x);
+       BN_free(y);
+       if (req == NULL)
+               eap_pwd_state(data, FAILURE);
+
+       return req;
+}
+
+
+static struct wpabuf *
+eap_pwd_build_req(struct eap_sm *sm, void *priv, u8 id)
+{
+       struct eap_pwd_data *data = priv;
+
+       switch (data->state) {
+        case PWD_ID_Req:
+               return eap_pwd_build_id_req(sm, data, id);
+        case PWD_Commit_Req:
+               return eap_pwd_build_commit_req(sm, data, id);
+        case PWD_Confirm_Req:
+               return eap_pwd_build_confirm_req(sm, data, id);
+        default:
+               wpa_printf(MSG_INFO, "EAP-pwd: Unknown state %d in build_req",
+                          data->state);
+               break;
+       }
+
+       return NULL;
+}
+
+
+static Boolean eap_pwd_check(struct eap_sm *sm, void *priv,
+                            struct wpabuf *respData)
+{
+       struct eap_pwd_data *data = priv;
+       const u8 *pos;
+       size_t len;
+
+       pos = eap_hdr_validate(EAP_VENDOR_IETF, EAP_TYPE_PWD, respData, &len);
+       if (pos == NULL || len < 1) {
+               wpa_printf(MSG_INFO, "EAP-pwd: Invalid frame");
+               return TRUE;
+       }
+
+       wpa_printf(MSG_DEBUG, "EAP-pwd: Received frame: opcode=%d", *pos);
+
+       if (data->state == PWD_ID_Req && *pos == EAP_PWD_OPCODE_ID_EXCH)
+               return FALSE;
+
+       if (data->state == PWD_Commit_Req &&
+           *pos == EAP_PWD_OPCODE_COMMIT_EXCH)
+               return FALSE;
+
+       if (data->state == PWD_Confirm_Req &&
+           *pos == EAP_PWD_OPCODE_CONFIRM_EXCH)
+               return FALSE;
+
+       wpa_printf(MSG_INFO, "EAP-pwd: Unexpected opcode=%d in state=%d",
+                  *pos, data->state);
+
+       return TRUE;
+}
+
+
+static void eap_pwd_process_id_resp(struct eap_sm *sm,
+                                   struct eap_pwd_data *data,
+                                   const u8 *payload, size_t payload_len)
+{
+       struct eap_pwd_id *id;
+
+       if (payload_len < sizeof(struct eap_pwd_id)) {
+               wpa_printf(MSG_INFO, "EAP-pwd: Invalid ID response");
+               return;
+       }
+
+       id = (struct eap_pwd_id *) payload;
+       if ((data->group_num != be_to_host16(id->group_num)) ||
+           (id->random_function != EAP_PWD_DEFAULT_RAND_FUNC) ||
+           (os_memcmp(id->token, (u8 *)&data->token, sizeof(data->token))) ||
+           (id->prf != EAP_PWD_DEFAULT_PRF)) {
+               wpa_printf(MSG_INFO, "EAP-pwd: peer changed parameters");
+               eap_pwd_state(data, FAILURE);
+               return;
+       }
+       data->id_peer = os_malloc(payload_len - sizeof(struct eap_pwd_id));
+       if (data->id_peer == NULL) {
+               wpa_printf(MSG_INFO, "EAP-PWD: memory allocation id fail");
+               return;
+       }
+       data->id_peer_len = payload_len - sizeof(struct eap_pwd_id);
+       os_memcpy(data->id_peer, id->identity, data->id_peer_len);
+       wpa_hexdump_ascii(MSG_DEBUG, "EAP-PWD (server): peer sent id of",
+                         data->id_peer, data->id_peer_len);
+
+       if ((data->grp = os_malloc(sizeof(EAP_PWD_group))) == NULL) {
+               wpa_printf(MSG_INFO, "EAP-PWD: failed to allocate memory for "
+                          "group");
+               return;
+       }
+       if (compute_password_element(data->grp, data->group_num,
+                                    data->password, data->password_len,
+                                    data->id_server, data->id_server_len,
+                                    data->id_peer, data->id_peer_len,
+                                    (u8 *) &data->token)) {
+               wpa_printf(MSG_INFO, "EAP-PWD (server): unable to compute "
+                          "PWE");
+               return;
+       }
+       wpa_printf(MSG_DEBUG, "EAP-PWD (server): computed %d bit PWE...",
+                  BN_num_bits(data->grp->prime));
+
+       eap_pwd_state(data, PWD_Commit_Req);
+}
+
+
+static void
+eap_pwd_process_commit_resp(struct eap_sm *sm, struct eap_pwd_data *data,
+                           const u8 *payload, size_t payload_len)
+{
+       u8 *ptr;
+       BIGNUM *x = NULL, *y = NULL, *cofactor = NULL;
+       EC_POINT *K = NULL, *point = NULL;
+       int res = 0;
+
+       wpa_printf(MSG_DEBUG, "EAP-pwd: Received commit response");
+
+       if (((data->peer_scalar = BN_new()) == NULL) ||
+           ((data->k = BN_new()) == NULL) ||
+           ((cofactor = BN_new()) == NULL) ||
+           ((x = BN_new()) == NULL) ||
+           ((y = BN_new()) == NULL) ||
+           ((point = EC_POINT_new(data->grp->group)) == NULL) ||
+           ((K = EC_POINT_new(data->grp->group)) == NULL) ||
+           ((data->peer_element = EC_POINT_new(data->grp->group)) == NULL)) {
+               wpa_printf(MSG_INFO, "EAP-PWD (server): peer data allocation "
+                          "fail");
+               goto fin;
+       }
+
+       if (!EC_GROUP_get_cofactor(data->grp->group, cofactor, NULL)) {
+               wpa_printf(MSG_INFO, "EAP-PWD (server): unable to get "
+                          "cofactor for curve");
+               goto fin;
+       }
+
+       /* element, x then y, followed by scalar */
+       ptr = (u8 *) payload;
+       BN_bin2bn(ptr, BN_num_bytes(data->grp->prime), x);
+       ptr += BN_num_bytes(data->grp->prime);
+       BN_bin2bn(ptr, BN_num_bytes(data->grp->prime), y);
+       ptr += BN_num_bytes(data->grp->prime);
+       BN_bin2bn(ptr, BN_num_bytes(data->grp->order), data->peer_scalar);
+       if (!EC_POINT_set_affine_coordinates_GFp(data->grp->group,
+                                                data->peer_element, x, y,
+                                                bnctx)) {
+               wpa_printf(MSG_INFO, "EAP-PWD (server): setting peer element "
+                          "fail");
+               goto fin;
+       }
+
+       /* check to ensure peer's element is not in a small sub-group */
+       if (BN_cmp(cofactor, BN_value_one())) {
+               if (!EC_POINT_mul(data->grp->group, point, NULL,
+                                 data->peer_element, cofactor, NULL)) {
+                       wpa_printf(MSG_INFO, "EAP-PWD (server): cannot "
+                                  "multiply peer element by order");
+                       goto fin;
+               }
+               if (EC_POINT_is_at_infinity(data->grp->group, point)) {
+                       wpa_printf(MSG_INFO, "EAP-PWD (server): peer element "
+                                  "is at infinity!\n");
+                       goto fin;
+               }
+       }
+
+       /* compute the shared key, k */
+       if ((!EC_POINT_mul(data->grp->group, K, NULL, data->grp->pwe,
+                          data->peer_scalar, bnctx)) ||
+           (!EC_POINT_add(data->grp->group, K, K, data->peer_element,
+                          bnctx)) ||
+           (!EC_POINT_mul(data->grp->group, K, NULL, K, data->private_value,
+                          bnctx))) {
+               wpa_printf(MSG_INFO, "EAP-PWD (server): computing shared key "
+                          "fail");
+               goto fin;
+       }
+
+       /* ensure that the shared key isn't in a small sub-group */
+       if (BN_cmp(cofactor, BN_value_one())) {
+               if (!EC_POINT_mul(data->grp->group, K, NULL, K, cofactor,
+                                 NULL)) {
+                       wpa_printf(MSG_INFO, "EAP-PWD (server): cannot "
+                                  "multiply shared key point by order!\n");
+                       goto fin;
+               }
+       }
+
+       /*
+        * This check is strictly speaking just for the case above where
+        * co-factor > 1 but it was suggested that even though this is probably
+        * never going to happen it is a simple and safe check "just to be
+        * sure" so let's be safe.
+        */
+       if (EC_POINT_is_at_infinity(data->grp->group, K)) {
+               wpa_printf(MSG_INFO, "EAP-PWD (server): shared key point is "
+                          "at infinity");
+               goto fin;
+       }
+       if (!EC_POINT_get_affine_coordinates_GFp(data->grp->group, K, data->k,
+                                                NULL, bnctx)) {
+               wpa_printf(MSG_INFO, "EAP-PWD (server): unable to extract "
+                          "shared secret from secret point");
+               goto fin;
+       }
+       res = 1;
+
+fin:
+       EC_POINT_free(K);
+       EC_POINT_free(point);
+       BN_free(cofactor);
+       BN_free(x);
+       BN_free(y);
+
+       if (res)
+               eap_pwd_state(data, PWD_Confirm_Req);
+       else
+               eap_pwd_state(data, FAILURE);
+}
+
+
+static void
+eap_pwd_process_confirm_resp(struct eap_sm *sm, struct eap_pwd_data *data,
+                            const u8 *payload, size_t payload_len)
+{
+       BIGNUM *x = NULL, *y = NULL;
+       HMAC_CTX ctx;
+       u32 cs;
+       u8 conf[SHA256_DIGEST_LENGTH], *cruft = NULL, *ptr;
+
+       /* build up the ciphersuite: group | random_function | prf */
+       ptr = (u8 *) &cs;
+       os_memcpy(ptr, &data->group_num, sizeof(u16));
+       ptr += sizeof(u16);
+       *ptr = EAP_PWD_DEFAULT_RAND_FUNC;
+       ptr += sizeof(u8);
+       *ptr = EAP_PWD_DEFAULT_PRF;
+
+       /* each component of the cruft will be at most as big as the prime */
+       if (((cruft = os_malloc(BN_num_bytes(data->grp->prime))) == NULL) ||
+           ((x = BN_new()) == NULL) || ((y = BN_new()) == NULL)) {
+               wpa_printf(MSG_INFO, "EAP-PWD (peer): allocation fail");
+               goto fin;
+       }
+
+       /*
+        * commit is H(k | peer_element | peer_scalar | server_element |
+        *             server_scalar | ciphersuite)
+        */
+       H_Init(&ctx);
+
+       /* k */
+       os_memset(cruft, 0, BN_num_bytes(data->grp->prime));
+       BN_bn2bin(data->k, cruft);
+       H_Update(&ctx, cruft, BN_num_bytes(data->grp->prime));
+
+       /* peer element: x, y */
+       if (!EC_POINT_get_affine_coordinates_GFp(data->grp->group,
+                                                data->peer_element, x, y,
+                                                bnctx)) {
+               wpa_printf(MSG_INFO, "EAP-PWD (server): confirm point "
+                          "assignment fail");
+               goto fin;
+       }
+       os_memset(cruft, 0, BN_num_bytes(data->grp->prime));
+       BN_bn2bin(x, cruft);
+       H_Update(&ctx, cruft, BN_num_bytes(data->grp->prime));
+       os_memset(cruft, 0, BN_num_bytes(data->grp->prime));
+       BN_bn2bin(y, cruft);
+       H_Update(&ctx, cruft, BN_num_bytes(data->grp->prime));
+
+       /* peer scalar */
+       os_memset(cruft, 0, BN_num_bytes(data->grp->prime));
+       BN_bn2bin(data->peer_scalar, cruft);
+       H_Update(&ctx, cruft, BN_num_bytes(data->grp->order));
+
+       /* server element: x, y */
+       if (!EC_POINT_get_affine_coordinates_GFp(data->grp->group,
+                                                data->my_element, x, y,
+                                                bnctx)) {
+               wpa_printf(MSG_INFO, "EAP-PWD (server): confirm point "
+                          "assignment fail");
+               goto fin;
+       }
+
+       os_memset(cruft, 0, BN_num_bytes(data->grp->prime));
+       BN_bn2bin(x, cruft);
+       H_Update(&ctx, cruft, BN_num_bytes(data->grp->prime));
+       os_memset(cruft, 0, BN_num_bytes(data->grp->prime));
+       BN_bn2bin(y, cruft);
+       H_Update(&ctx, cruft, BN_num_bytes(data->grp->prime));
+
+       /* server scalar */
+       os_memset(cruft, 0, BN_num_bytes(data->grp->prime));
+       BN_bn2bin(data->my_scalar, cruft);
+       H_Update(&ctx, cruft, BN_num_bytes(data->grp->order));
+
+       /* ciphersuite */
+       os_memset(cruft, 0, BN_num_bytes(data->grp->prime));
+       H_Update(&ctx, (u8 *)&cs, sizeof(u32));
+
+       /* all done */
+       H_Final(&ctx, conf);
+
+       ptr = (u8 *) payload;
+       if (os_memcmp(conf, ptr, SHA256_DIGEST_LENGTH)) {
+               wpa_printf(MSG_INFO, "EAP-PWD (server): confirm did not "
+                          "verify");
+               goto fin;
+       }
+
+       wpa_printf(MSG_DEBUG, "EAP-pwd (server): confirm verified");
+       if (compute_keys(data->grp, bnctx, data->k, data->my_element,
+                        data->peer_element, data->my_scalar,
+                        data->peer_scalar, &cs, data->msk, data->emsk) < 0)
+               eap_pwd_state(data, FAILURE);
+       else
+               eap_pwd_state(data, SUCCESS);
+
+fin:
+       os_free(cruft);
+       BN_free(x);
+       BN_free(y);
+}
+
+
+static void eap_pwd_process(struct eap_sm *sm, void *priv,
+                           struct wpabuf *respData)
+{
+       struct eap_pwd_data *data = priv;
+       const u8 *pos;
+       size_t len;
+       u8 exch;
+
+       pos = eap_hdr_validate(EAP_VENDOR_IETF, EAP_TYPE_PWD, respData, &len);
+       if ((pos == NULL) || (len < 1)) {
+               wpa_printf(MSG_INFO, "Bad EAP header! pos %s and len = %d",
+                          (pos == NULL) ? "is NULL" : "is not NULL",
+                          (int) len);
+               return;
+       }
+
+       exch = *pos & 0x3f;
+       switch (exch) {
+       case EAP_PWD_OPCODE_ID_EXCH:
+               eap_pwd_process_id_resp(sm, data, pos + 1, len - 1);
+               break;
+       case EAP_PWD_OPCODE_COMMIT_EXCH:
+               eap_pwd_process_commit_resp(sm, data, pos + 1, len - 1);
+               break;
+        case EAP_PWD_OPCODE_CONFIRM_EXCH:
+               eap_pwd_process_confirm_resp(sm, data, pos + 1, len - 1);
+               break;
+       }
+}
+
+
+static u8 * eap_pwd_getkey(struct eap_sm *sm, void *priv, size_t *len)
+{
+       struct eap_pwd_data *data = priv;
+       u8 *key;
+
+       if (data->state != SUCCESS)
+               return NULL;
+
+       key = os_malloc(EAP_MSK_LEN);
+       if (key == NULL)
+               return NULL;
+
+       os_memcpy(key, data->msk, EAP_MSK_LEN);
+       *len = EAP_MSK_LEN;
+
+       return key;
+}
+
+
+static u8 * eap_pwd_get_emsk(struct eap_sm *sm, void *priv, size_t *len)
+{
+       struct eap_pwd_data *data = priv;
+       u8 *key;
+
+       if (data->state != SUCCESS)
+               return NULL;
+
+       key = os_malloc(EAP_EMSK_LEN);
+       if (key == NULL)
+               return NULL;
+
+       os_memcpy(key, data->emsk, EAP_EMSK_LEN);
+       *len = EAP_EMSK_LEN;
+
+       return key;
+}
+
+
+static Boolean eap_pwd_is_success(struct eap_sm *sm, void *priv)
+{
+       struct eap_pwd_data *data = priv;
+       return data->state == SUCCESS;
+}
+
+
+static Boolean eap_pwd_is_done(struct eap_sm *sm, void *priv)
+{
+       struct eap_pwd_data *data = priv;
+       return (data->state == SUCCESS) || (data->state == FAILURE);
+}
+
+
+int eap_server_pwd_register(void)
+{
+       struct eap_method *eap;
+       int ret;
+       struct timeval tp;
+       struct timezone tz;
+       u32 sr;
+
+       EVP_add_digest(EVP_sha256());
+
+       sr = 0xdeaddada;
+       (void) gettimeofday(&tp, &tz);
+       sr ^= (tp.tv_sec ^ tp.tv_usec);
+       srandom(sr);
+
+       eap = eap_server_method_alloc(EAP_SERVER_METHOD_INTERFACE_VERSION,
+                                     EAP_VENDOR_IETF, EAP_TYPE_PWD,
+                                     "PWD");
+       if (eap == NULL)
+               return -1;
+
+       eap->init = eap_pwd_init;
+       eap->reset = eap_pwd_reset;
+       eap->buildReq = eap_pwd_build_req;
+       eap->check = eap_pwd_check;
+       eap->process = eap_pwd_process;
+       eap->isDone = eap_pwd_is_done;
+       eap->getKey = eap_pwd_getkey;
+       eap->get_emsk = eap_pwd_get_emsk;
+       eap->isSuccess = eap_pwd_is_success;
+
+       ret = eap_server_method_register(eap);
+       if (ret)
+               eap_server_method_free(eap);
+       return ret;
+}
+
index a3b1c92..841a1c5 100644 (file)
@@ -833,6 +833,7 @@ eapol_auth_alloc(struct eapol_authenticator *eapol, const u8 *addr,
        eap_conf.assoc_p2p_ie = assoc_p2p_ie;
        eap_conf.peer_addr = addr;
        eap_conf.fragment_size = eapol->conf.fragment_size;
+       eap_conf.pwd_group = eapol->conf.pwd_group;
        sm->eap = eap_server_sm_init(sm, &eapol_cb, &eap_conf);
        if (sm->eap == NULL) {
                eapol_auth_free(sm);
@@ -1037,6 +1038,7 @@ static int eapol_auth_conf_clone(struct eapol_auth_config *dst,
        dst->msg_ctx = src->msg_ctx;
        dst->eap_sim_db_priv = src->eap_sim_db_priv;
        os_free(dst->eap_req_id_text);
+       dst->pwd_group = src->pwd_group;
        if (src->eap_req_id_text) {
                dst->eap_req_id_text = os_malloc(src->eap_req_id_text_len);
                if (dst->eap_req_id_text == NULL)
index 51058c6..59a10b4 100644 (file)
@@ -41,6 +41,7 @@ struct eapol_auth_config {
        int tnc;
        struct wps_context *wps;
        int fragment_size;
+       u16 pwd_group;
 
        /* Opaque context pointer to owner data for callback functions */
        void *ctx;
index f8780a6..6f1c3a5 100644 (file)
@@ -222,6 +222,13 @@ struct radius_server_data {
        int tnc;
 
        /**
+        * pwd_group - The D-H group assigned for EAP-pwd
+        *
+        * If EAP-pwd is not used it can be set to zero.
+        */
+       u16 pwd_group;
+
+       /**
         * wps - Wi-Fi Protected Setup context
         *
         * If WPS is used with an external RADIUS server (which is quite
@@ -505,6 +512,7 @@ radius_server_get_new_session(struct radius_server_data *data,
        eap_conf.eap_sim_aka_result_ind = data->eap_sim_aka_result_ind;
        eap_conf.tnc = data->tnc;
        eap_conf.wps = data->wps;
+       eap_conf.pwd_group = data->pwd_group;
        sess->eap = eap_server_sm_init(sess, &radius_server_eapol_cb,
                                       &eap_conf);
        if (sess->eap == NULL) {
@@ -1259,6 +1267,7 @@ radius_server_init(struct radius_server_conf *conf)
        data->eap_sim_aka_result_ind = conf->eap_sim_aka_result_ind;
        data->tnc = conf->tnc;
        data->wps = conf->wps;
+       data->pwd_group = conf->pwd_group;
        if (conf->eap_req_id_text) {
                data->eap_req_id_text = os_malloc(conf->eap_req_id_text_len);
                if (data->eap_req_id_text) {
index f9c951d..126e314 100644 (file)
@@ -143,6 +143,13 @@ struct radius_server_conf {
        int tnc;
 
        /**
+        * pwd_group - EAP-pwd D-H group
+        *
+        * This is used to select which D-H group to use with EAP-pwd.
+        */
+       u16 pwd_group;
+
+       /**
         * wps - Wi-Fi Protected Setup context
         *
         * If WPS is used with an external RADIUS server (which is quite
index c113dd6..a113cca 100644 (file)
@@ -474,6 +474,14 @@ NEED_SHA256=y
 NEED_AES_OMAC1=y
 endif
 
+ifdef CONFIG_EAP_PWD
+CFLAGS += -DEAP_PWD
+OBJS += ../src/eap_peer/eap_pwd.o ../src/eap_common/eap_pwd_common.o
+OBJS_h += ../src/eap_server/eap_pwd.o
+CONFIG_IEEE8021X_EAPOL=y
+NEED_SHA256=y
+endif
+
 ifdef CONFIG_WPS
 ifdef CONFIG_WPS2
 CFLAGS += -DCONFIG_WPS2
index f668874..e5f43aa 100644 (file)
@@ -130,6 +130,10 @@ int eap_register_methods(void)
                ret = eap_peer_tnc_register();
 #endif /* EAP_TNC */
 
+#ifdef EAP_PWD
+       if (ret == 0)
+               ret = eap_peer_pwd_register();
+#endif /* EAP_PWD */
 
 #ifdef EAP_SERVER_IDENTITY
        if (ret == 0)
@@ -231,5 +235,10 @@ int eap_register_methods(void)
                ret = eap_server_tnc_register();
 #endif /* EAP_SERVER_TNC */
 
+#ifdef EAP_SERVER_PWD
+       if (ret == 0)
+               ret = eap_server_pwd_register();
+#endif /* EAP_SERVER_PWD */
+
        return ret;
 }