From 53650bcab4fd0fc8283072fcef3634c6ecbf8f50 Mon Sep 17 00:00:00 2001 From: Jouni Malinen Date: Sat, 6 Nov 2010 22:57:49 +0200 Subject: [PATCH] wlantest: Add PTK derivation based on passphrases Allow pre-configuration of passphrases (-p) 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). --- wlantest/Makefile | 1 + wlantest/bss.c | 62 +++++++++++++++- wlantest/rx_data.c | 169 +++++++++++++++++++++++++++++++++++++++++++- wlantest/rx_mgmt.c | 4 +- wlantest/wlantest.c | 37 +++++++++- wlantest/wlantest.h | 23 +++++- 6 files changed, 285 insertions(+), 11 deletions(-) diff --git a/wlantest/Makefile b/wlantest/Makefile index 8e40c8ee3..53278c133 100644 --- 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 ec26b824a..156d8b37f 100644 --- 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 f67498200..de34bf4d8 100644 --- 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 2100a8ad7..5b630c6f3 100644 --- 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 9856368a7..14cef1ab0 100644 --- 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] [-r]\n"); + printf("wlantest [-ddhqq] [-i] [-r] " + "[-p]\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 10ca61c99..31d903ee2 100644 --- 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);