wlantest: Add PTK derivation based on passphrases

Allow pre-configuration of passphrases (-p<passphrase>) to provide
enough information for wlantest to be able to derive PMK for each
BSS and PTK for each STA going through 4-Way Handshake (at least
message 2 and 3 needs to be received).

diff --git a/wlantest/Makefile b/wlantest/Makefile
index 8e40c8ee34b4eb57c79e825dcea611c4f0e26065..53278c1339798a125b3bd538ef3161a39c3d42ac 100644 (file)
--- a/wlantest/Makefile
+++ b/wlantest/Makefile
@@ -40,6 +40,7 @@ OBJS_lib += ../src/utils/libutils.a
 OBJS_lib += ../src/crypto/libcrypto.a
 
 OBJS += ../src/common/ieee802_11_common.o
+OBJS += ../src/common/wpa_common.o
 
 OBJS += wlantest.o
 OBJS += readpcap.o

diff --git a/wlantest/bss.c b/wlantest/bss.c
index ec26b824a8aa853f58713fe83ae0fe085038547a..156d8b37faa8b433fe82b02e0adf509d4b0f2321 100644 (file)
--- a/wlantest/bss.c
+++ b/wlantest/bss.c
@@ -16,6 +16,7 @@
 
 #include "utils/common.h"
 #include "common/ieee802_11_common.h"
+#include "crypto/sha1.h"
 #include "wlantest.h"
 
 
@@ -35,6 +36,7 @@ struct wlantest_bss * bss_get(struct wlantest *wt, const u8 *bssid)
        if (bss == NULL)
                return NULL;
        dl_list_init(&bss->sta);
+       dl_list_init(&bss->pmk);
        os_memcpy(bss->bssid, bssid, ETH_ALEN);
        dl_list_add(&wt->bss, &bss->list);
        wpa_printf(MSG_DEBUG, "Discovered new BSS - " MACSTR,
@@ -43,17 +45,63 @@ struct wlantest_bss * bss_get(struct wlantest *wt, const u8 *bssid)
 }
 
 
+static void pmk_deinit(struct wlantest_pmk *pmk)
+{
+       dl_list_del(&pmk->list);
+       os_free(pmk);
+}
+
+
 void bss_deinit(struct wlantest_bss *bss)
 {
        struct wlantest_sta *sta, *n;
+       struct wlantest_pmk *pmk, *np;
        dl_list_for_each_safe(sta, n, &bss->sta, struct wlantest_sta, list)
                sta_deinit(sta);
+       dl_list_for_each_safe(pmk, np, &bss->pmk, struct wlantest_pmk, list)
+               pmk_deinit(pmk);
        dl_list_del(&bss->list);
        os_free(bss);
 }
 
 
-void bss_update(struct wlantest_bss *bss, struct ieee802_11_elems *elems)
+static void bss_add_pmk(struct wlantest *wt, struct wlantest_bss *bss)
+{
+       struct wlantest_passphrase *p;
+       struct wlantest_pmk *pmk;
+
+       dl_list_for_each(p, &wt->passphrase, struct wlantest_passphrase, list)
+       {
+               if (!is_zero_ether_addr(p->bssid) &&
+                   os_memcmp(p->bssid, bss->bssid, ETH_ALEN) != 0)
+                       continue;
+               if (p->ssid_len &&
+                   (p->ssid_len != bss->ssid_len ||
+                    os_memcmp(p->ssid, bss->ssid, p->ssid_len) != 0))
+                       continue;
+
+               pmk = os_zalloc(sizeof(*pmk));
+               if (pmk == NULL)
+                       break;
+               if (pbkdf2_sha1(p->passphrase, (char *) bss->ssid,
+                               bss->ssid_len, 4096,
+                               pmk->pmk, sizeof(pmk->pmk)) < 0) {
+                       os_free(pmk);
+                       continue;
+               }
+
+               wpa_printf(MSG_INFO, "Add possible PMK for BSSID " MACSTR
+                          " based on passphrase '%s'",
+                          MAC2STR(bss->bssid), p->passphrase);
+               wpa_hexdump(MSG_DEBUG, "Possible PMK",
+                           pmk->pmk, sizeof(pmk->pmk));
+               dl_list_add(&bss->pmk, &pmk->list);
+       }
+}
+
+
+void bss_update(struct wlantest *wt, struct wlantest_bss *bss,
+               struct ieee802_11_elems *elems)
 {
        if (elems->ssid == NULL || elems->ssid_len > 32) {
                wpa_printf(MSG_INFO, "Invalid or missing SSID in a Beacon "
@@ -62,8 +110,16 @@ void bss_update(struct wlantest_bss *bss, struct ieee802_11_elems *elems)
                return;
        }
 
-       os_memcpy(bss->ssid, elems->ssid, elems->ssid_len);
-       bss->ssid_len = elems->ssid_len;
+       if (bss->ssid_len != elems->ssid_len ||
+           os_memcmp(bss->ssid, elems->ssid, bss->ssid_len) != 0) {
+               wpa_printf(MSG_DEBUG, "Store SSID '%s' for BSSID " MACSTR,
+                          wpa_ssid_txt(elems->ssid, elems->ssid_len),
+                          MAC2STR(bss->bssid));
+               os_memcpy(bss->ssid, elems->ssid, elems->ssid_len);
+               bss->ssid_len = elems->ssid_len;
+               bss_add_pmk(wt, bss);
+       }
+
 
        if (elems->rsn_ie == NULL) {
                if (bss->rsnie[0]) {

diff --git a/wlantest/rx_data.c b/wlantest/rx_data.c
index f67498200824e26c14b2d712bda856807c70d75f..de34bf4d8aa18d6c30cb9a353e818133f8567fc2 100644 (file)
--- a/wlantest/rx_data.c
+++ b/wlantest/rx_data.c
@@ -59,35 +59,193 @@ static const char * data_stype(u16 stype)
 }
 
 
+static int check_mic(const u8 *kck, int ver, const u8 *data, size_t len)
+{
+       u8 *buf;
+       int ret = -1;
+       struct ieee802_1x_hdr *hdr;
+       struct wpa_eapol_key *key;
+       u8 rx_mic[16];
+
+       buf = os_malloc(len);
+       if (buf == NULL)
+               return -1;
+       os_memcpy(buf, data, len);
+       hdr = (struct ieee802_1x_hdr *) buf;
+       key = (struct wpa_eapol_key *) (hdr + 1);
+
+       os_memcpy(rx_mic, key->key_mic, 16);
+       os_memset(key->key_mic, 0, 16);
+
+       if (wpa_eapol_key_mic(kck, ver, buf, len, key->key_mic) == 0 &&
+           os_memcmp(rx_mic, key->key_mic, 16) == 0)
+               ret = 0;
+
+       os_free(buf);
+
+       return ret;
+}
+
+
 static void rx_data_eapol_key_1_of_4(struct wlantest *wt, const u8 *dst,
                                     const u8 *src, const u8 *data, size_t len)
 {
+       struct wlantest_bss *bss;
+       struct wlantest_sta *sta;
+       const struct ieee802_1x_hdr *eapol;
+       const struct wpa_eapol_key *hdr;
+
        wpa_printf(MSG_DEBUG, "EAPOL-Key 1/4 " MACSTR " -> " MACSTR,
                   MAC2STR(src), MAC2STR(dst));
+       bss = bss_get(wt, src);
+       if (bss == NULL)
+               return;
+       sta = sta_get(bss, dst);
+       if (sta == NULL)
+               return;
+
+       eapol = (const struct ieee802_1x_hdr *) data;
+       hdr = (const struct wpa_eapol_key *) (eapol + 1);
+       os_memcpy(sta->anonce, hdr->key_nonce, WPA_NONCE_LEN);
+}
+
+
+static void derive_ptk(struct wlantest_bss *bss, struct wlantest_sta *sta,
+                      u16 ver, const u8 *data, size_t len)
+{
+       struct wlantest_pmk *pmk;
+
+       dl_list_for_each(pmk, &bss->pmk, struct wlantest_pmk, list) {
+               struct wpa_ptk ptk;
+               size_t ptk_len = 48; /* FIX: 64 for TKIP */
+               wpa_pmk_to_ptk(pmk->pmk, sizeof(pmk->pmk),
+                              "Pairwise key expansion",
+                              bss->bssid, sta->addr, sta->anonce, sta->snonce,
+                              (u8 *) &ptk, ptk_len,
+                              0 /* FIX: SHA256 based on AKM */);
+               if (check_mic(ptk.kck, ver,
+                             data, len) < 0)
+                       continue;
+
+               wpa_printf(MSG_INFO, "Derived PTK for STA " MACSTR " BSSID "
+                          MACSTR ")",
+                          MAC2STR(sta->addr), MAC2STR(bss->bssid));
+               os_memcpy(&sta->ptk, &ptk, sizeof(ptk));
+               sta->ptk_set = 1;
+               break;
+       }
 }
 
 
 static void rx_data_eapol_key_2_of_4(struct wlantest *wt, const u8 *dst,
                                     const u8 *src, const u8 *data, size_t len)
 {
+       struct wlantest_bss *bss;
+       struct wlantest_sta *sta;
+       const struct ieee802_1x_hdr *eapol;
+       const struct wpa_eapol_key *hdr;
+       u16 key_info;
+
        wpa_printf(MSG_DEBUG, "EAPOL-Key 2/4 " MACSTR " -> " MACSTR,
                   MAC2STR(src), MAC2STR(dst));
+       bss = bss_get(wt, dst);
+       if (bss == NULL)
+               return;
+       sta = sta_get(bss, src);
+       if (sta == NULL)
+               return;
+
+       eapol = (const struct ieee802_1x_hdr *) data;
+       hdr = (const struct wpa_eapol_key *) (eapol + 1);
+       os_memcpy(sta->snonce, hdr->key_nonce, WPA_NONCE_LEN);
+       key_info = WPA_GET_BE16(hdr->key_info);
+       derive_ptk(bss, sta, key_info & WPA_KEY_INFO_TYPE_MASK, data, len);
 }
 
 
 static void rx_data_eapol_key_3_of_4(struct wlantest *wt, const u8 *dst,
                                     const u8 *src, const u8 *data, size_t len)
 {
+       struct wlantest_bss *bss;
+       struct wlantest_sta *sta;
+       const struct ieee802_1x_hdr *eapol;
+       const struct wpa_eapol_key *hdr;
+       int recalc = 0;
+       u16 key_info;
+
        wpa_printf(MSG_DEBUG, "EAPOL-Key 3/4 " MACSTR " -> " MACSTR,
                   MAC2STR(src), MAC2STR(dst));
+       bss = bss_get(wt, src);
+       if (bss == NULL)
+               return;
+       sta = sta_get(bss, dst);
+       if (sta == NULL)
+               return;
+
+       eapol = (const struct ieee802_1x_hdr *) data;
+       hdr = (const struct wpa_eapol_key *) (eapol + 1);
+       key_info = WPA_GET_BE16(hdr->key_info);
+       if (os_memcmp(sta->anonce, hdr->key_nonce, WPA_NONCE_LEN) != 0) {
+               wpa_printf(MSG_INFO, "EAPOL-Key ANonce mismatch between 1/4 "
+                          "and 3/4");
+               recalc = 1;
+       }
+       os_memcpy(sta->anonce, hdr->key_nonce, WPA_NONCE_LEN);
+       if (recalc) {
+               derive_ptk(bss, sta, key_info & WPA_KEY_INFO_TYPE_MASK,
+                          data, len);
+       }
+
+       if (!sta->ptk_set) {
+               wpa_printf(MSG_DEBUG, "No PTK known to process EAPOL-Key 3/4");
+               return;
+       }
+
+       if (check_mic(sta->ptk.kck, key_info & WPA_KEY_INFO_TYPE_MASK,
+                     data, len) < 0) {
+               wpa_printf(MSG_INFO, "Mismatch in EAPOL-Key 3/4 MIC");
+               return;
+       }
+       wpa_printf(MSG_DEBUG, "Valid MIC found in EAPOL-Key 3/4");
+
+       /* TODO: decrypt Key Data and store GTK, IGTK */
 }
 
 
 static void rx_data_eapol_key_4_of_4(struct wlantest *wt, const u8 *dst,
                                     const u8 *src, const u8 *data, size_t len)
 {
+       struct wlantest_bss *bss;
+       struct wlantest_sta *sta;
+       const struct ieee802_1x_hdr *eapol;
+       const struct wpa_eapol_key *hdr;
+       u16 key_info;
+
        wpa_printf(MSG_DEBUG, "EAPOL-Key 4/4 " MACSTR " -> " MACSTR,
                   MAC2STR(src), MAC2STR(dst));
+       bss = bss_get(wt, dst);
+       if (bss == NULL)
+               return;
+       sta = sta_get(bss, src);
+       if (sta == NULL)
+               return;
+
+       eapol = (const struct ieee802_1x_hdr *) data;
+       hdr = (const struct wpa_eapol_key *) (eapol + 1);
+       key_info = WPA_GET_BE16(hdr->key_info);
+
+       if (!sta->ptk_set) {
+               wpa_printf(MSG_DEBUG, "No PTK known to process EAPOL-Key 4/4");
+               return;
+       }
+
+       if (sta->ptk_set &&
+           check_mic(sta->ptk.kck, key_info & WPA_KEY_INFO_TYPE_MASK,
+                     data, len) < 0) {
+               wpa_printf(MSG_INFO, "Mismatch in EAPOL-Key 4/4 MIC");
+               return;
+       }
+       wpa_printf(MSG_DEBUG, "Valid MIC found in EAPOL-Key 4/4");
 }
 
 
@@ -111,16 +269,20 @@ static void rx_data_eapol_key(struct wlantest *wt, const u8 *dst,
                              const u8 *src, const u8 *data, size_t len,
                              int prot)
 {
+       const struct ieee802_1x_hdr *eapol;
        const struct wpa_eapol_key *hdr;
        u16 key_info, key_length, ver, key_data_length;
 
-       wpa_hexdump(MSG_MSGDUMP, "EAPOL-Key", data, len);
+       eapol = (const struct ieee802_1x_hdr *) data;
+       hdr = (const struct wpa_eapol_key *) (eapol + 1);
+
+       wpa_hexdump(MSG_MSGDUMP, "EAPOL-Key",
+                   (const u8 *) hdr, len - sizeof(*eapol));
        if (len < sizeof(*hdr)) {
                wpa_printf(MSG_INFO, "Too short EAPOL-Key frame from " MACSTR,
                           MAC2STR(src));
                return;
        }
-       hdr = (const struct wpa_eapol_key *) data;
 
        if (hdr->type == EAPOL_KEY_TYPE_RC4) {
                /* TODO: EAPOL-Key RC4 for WEP */
@@ -264,7 +426,8 @@ static void rx_data_eapol(struct wlantest *wt, const u8 *dst, const u8 *src,
                wpa_hexdump(MSG_MSGDUMP, "EAPOL-Logoff", p, length);
                break;
        case IEEE802_1X_TYPE_EAPOL_KEY:
-               rx_data_eapol_key(wt, dst, src, p, length, prot);
+               rx_data_eapol_key(wt, dst, src, data, sizeof(*hdr) + length,
+                                 prot);
                break;
        case IEEE802_1X_TYPE_EAPOL_ENCAPSULATED_ASF_ALERT:
                wpa_hexdump(MSG_MSGDUMP, "EAPOL - Encapsulated ASF alert",

diff --git a/wlantest/rx_mgmt.c b/wlantest/rx_mgmt.c
index 2100a8ad754385f87cf432b98defdf02aac4b6c0..5b630c6f30355e6c2e44fdd7d78c393a769547c3 100644 (file)
--- a/wlantest/rx_mgmt.c
+++ b/wlantest/rx_mgmt.c
@@ -76,7 +76,7 @@ static void rx_mgmt_beacon(struct wlantest *wt, const u8 *data, size_t len)
                return;
        }
 
-       bss_update(bss, &elems);
+       bss_update(wt, bss, &elems);
 }
 
 
@@ -103,7 +103,7 @@ static void rx_mgmt_probe_resp(struct wlantest *wt, const u8 *data, size_t len)
                return;
        }
 
-       bss_update(bss, &elems);
+       bss_update(wt, bss, &elems);
 }
 
 

diff --git a/wlantest/wlantest.c b/wlantest/wlantest.c
index 9856368a747aa07f835c55491eb83ebf5e176a55..14cef1ab0cfb1ae93adc558134e1c37a787bdcb5 100644 (file)
--- a/wlantest/wlantest.c
+++ b/wlantest/wlantest.c
@@ -20,6 +20,7 @@
 
 
 extern int wpa_debug_level;
+extern int wpa_debug_show_keys;
 
 
 static void wlantest_terminate(int sig, void *signal_ctx)
@@ -30,7 +31,15 @@ static void wlantest_terminate(int sig, void *signal_ctx)
 
 static void usage(void)
 {
-       printf("wlantest [-ddhqq] [-i<ifname>] [-r<pcap file>]\n");
+       printf("wlantest [-ddhqq] [-i<ifname>] [-r<pcap file>] "
+              "[-p<passphrase>]\n");
+}
+
+
+static void passphrase_deinit(struct wlantest_passphrase *p)
+{
+       dl_list_del(&p->list);
+       os_free(p);
 }
 
 
@@ -38,6 +47,7 @@ static void wlantest_init(struct wlantest *wt)
 {
        os_memset(wt, 0, sizeof(*wt));
        wt->monitor_sock = -1;
+       dl_list_init(&wt->passphrase);
        dl_list_init(&wt->bss);
 }
 
@@ -45,10 +55,29 @@ static void wlantest_init(struct wlantest *wt)
 static void wlantest_deinit(struct wlantest *wt)
 {
        struct wlantest_bss *bss, *n;
+       struct wlantest_passphrase *p, *pn;
        if (wt->monitor_sock >= 0)
                monitor_deinit(wt);
        dl_list_for_each_safe(bss, n, &wt->bss, struct wlantest_bss, list)
                bss_deinit(bss);
+       dl_list_for_each_safe(p, pn, &wt->passphrase,
+                             struct wlantest_passphrase, list)
+               passphrase_deinit(p);
+}
+
+
+static void add_passphrase(struct wlantest *wt, const char *passphrase)
+{
+       struct wlantest_passphrase *p;
+       size_t len = os_strlen(passphrase);
+
+       if (len < 8 || len > 63)
+               return;
+       p = os_zalloc(sizeof(*p));
+       if (p == NULL)
+               return;
+       os_memcpy(p->passphrase, passphrase, len);
+       dl_list_add(&wt->passphrase, &p->list);
 }
 
 
@@ -60,6 +89,7 @@ int main(int argc, char *argv[])
        struct wlantest wt;
 
        wpa_debug_level = MSG_INFO;
+       wpa_debug_show_keys = 1;
 
        if (os_program_init())
                return -1;
@@ -67,7 +97,7 @@ int main(int argc, char *argv[])
        wlantest_init(&wt);
 
        for (;;) {
-               c = getopt(argc, argv, "dhi:r:q");
+               c = getopt(argc, argv, "dhi:p:qr:");
                if (c < 0)
                        break;
                switch (c) {
@@ -81,6 +111,9 @@ int main(int argc, char *argv[])
                case 'i':
                        ifname = optarg;
                        break;
+               case 'p':
+                       add_passphrase(&wt, optarg);
+                       break;
                case 'q':
                        wpa_debug_level++;
                        break;

diff --git a/wlantest/wlantest.h b/wlantest/wlantest.h
index 10ca61c994413d73047b019cbdf68a0c9d480e75..31d903ee247743ef2c46fd6a3f57c71a72dd6a41 100644 (file)
--- a/wlantest/wlantest.h
+++ b/wlantest/wlantest.h
@@ -16,10 +16,24 @@
 #define WLANTEST_H
 
 #include "utils/list.h"
+#include "common/wpa_common.h"
 
 struct ieee802_11_elems;
 
 
+struct wlantest_passphrase {
+       struct dl_list list;
+       char passphrase[64];
+       u8 ssid[32];
+       size_t ssid_len;
+       u8 bssid[ETH_ALEN];
+};
+
+struct wlantest_pmk {
+       struct dl_list list;
+       u8 pmk[32];
+};
+
 struct wlantest_sta {
        struct dl_list list;
        u8 addr[ETH_ALEN];
@@ -30,6 +44,10 @@ struct wlantest_sta {
        } state;
        u16 aid;
        u8 rsnie[257]; /* WPA/RSN IE */
+       u8 anonce[32]; /* ANonce from the previous EAPOL-Key msg 1/4 or 3/4 */
+       u8 snonce[32]; /* SNonce from the previous EAPOL-Key msg 2/4 */
+       struct wpa_ptk ptk; /* Derived PTK */
+       int ptk_set;
 };
 
 struct wlantest_bss {
@@ -43,11 +61,13 @@ struct wlantest_bss {
        u8 wpaie[257];
        u8 rsnie[257];
        struct dl_list sta; /* struct wlantest_sta */
+       struct dl_list pmk; /* struct wlantest_pmk */
 };
 
 struct wlantest {
        int monitor_sock;
 
+       struct dl_list passphrase; /* struct wlantest_passphrase */
        struct dl_list bss; /* struct wlantest_bss */
 
        unsigned int rx_mgmt;
@@ -66,7 +86,8 @@ void rx_data(struct wlantest *wt, const u8 *data, size_t len);
 
 struct wlantest_bss * bss_get(struct wlantest *wt, const u8 *bssid);
 void bss_deinit(struct wlantest_bss *bss);
-void bss_update(struct wlantest_bss *bss, struct ieee802_11_elems *elems);
+void bss_update(struct wlantest *wt, struct wlantest_bss *bss,
+               struct ieee802_11_elems *elems);
 
 struct wlantest_sta * sta_get(struct wlantest_bss *bss, const u8 *addr);
 void sta_deinit(struct wlantest_sta *sta);