Annotate places depending on strong random numbers

This commit adds a new wrapper, random_get_bytes(), that is currently
defined to use os_get_random() as is. The places using
random_get_bytes() depend on the returned value being strong random
number, i.e., something that is infeasible for external device to
figure out. These values are used either directly as a key or as
nonces/challenges that are used as input for key derivation or
authentication.

The remaining direct uses of os_get_random() do not need as strong
random numbers to function correctly.

12 files changed, 26 insertions, 14 deletions

diff --git a/src/eap_server/eap_server_aka.c b/src/eap_server/eap_server_aka.c
index 4e7db48..42cbdce 100644
--- a/src/eap_server/eap_server_aka.c
+++ b/src/eap_server/eap_server_aka.c
@@ -17,6 +17,7 @@
 #include "common.h"
 #include "crypto/sha256.h"
 #include "crypto/crypto.h"
+#include "crypto/random.h"
 #include "eap_common/eap_sim_common.h"
 #include "eap_server/eap_i.h"
 #include "eap_server/eap_sim_db.h"
@@ -440,7 +441,7 @@ static struct wpabuf * eap_aka_build_reauth(struct eap_sm *sm,
 
 	wpa_printf(MSG_DEBUG, "EAP-AKA: Generating Re-authentication");
 
-	if (os_get_random(data->nonce_s, EAP_SIM_NONCE_S_LEN))
+	if (random_get_bytes(data->nonce_s, EAP_SIM_NONCE_S_LEN))
 		return NULL;
 	wpa_hexdump_key(MSG_MSGDUMP, "EAP-AKA: NONCE_S",
 			data->nonce_s, EAP_SIM_NONCE_S_LEN);
diff --git a/src/eap_server/eap_server_fast.c b/src/eap_server/eap_server_fast.c
index 39beb33..ba17e98 100644
--- a/src/eap_server/eap_server_fast.c
+++ b/src/eap_server/eap_server_fast.c
@@ -18,6 +18,7 @@
 #include "crypto/aes_wrap.h"
 #include "crypto/sha1.h"
 #include "crypto/tls.h"
+#include "crypto/random.h"
 #include "eap_common/eap_tlv_common.h"
 #include "eap_common/eap_fast_common.h"
 #include "eap_i.h"
@@ -642,7 +643,7 @@ static struct wpabuf * eap_fast_build_crypto_binding(
 	binding->version = EAP_FAST_VERSION;
 	binding->received_version = data->peer_version;
 	binding->subtype = EAP_TLV_CRYPTO_BINDING_SUBTYPE_REQUEST;
-	if (os_get_random(binding->nonce, sizeof(binding->nonce)) < 0) {
+	if (random_get_bytes(binding->nonce, sizeof(binding->nonce)) < 0) {
 		wpabuf_free(buf);
 		return NULL;
 	}
@@ -692,7 +693,7 @@ static struct wpabuf * eap_fast_build_pac(struct eap_sm *sm,
 	struct eap_tlv_result_tlv *result;
 	struct os_time now;
 
-	if (os_get_random(pac_key, EAP_FAST_PAC_KEY_LEN) < 0 ||
+	if (random_get_bytes(pac_key, EAP_FAST_PAC_KEY_LEN) < 0 ||
 	    os_get_time(&now) < 0)
 		return NULL;
 	wpa_hexdump_key(MSG_DEBUG, "EAP-FAST: Generated PAC-Key",
diff --git a/src/eap_server/eap_server_gpsk.c b/src/eap_server/eap_server_gpsk.c
index d0c7559..a794806 100644
--- a/src/eap_server/eap_server_gpsk.c
+++ b/src/eap_server/eap_server_gpsk.c
@@ -15,6 +15,7 @@
 #include "includes.h"
 
 #include "common.h"
+#include "crypto/random.h"
 #include "eap_server/eap_i.h"
 #include "eap_common/eap_gpsk_common.h"
 
@@ -120,7 +121,7 @@ static struct wpabuf * eap_gpsk_build_gpsk_1(struct eap_sm *sm,
 
 	wpa_printf(MSG_DEBUG, "EAP-GPSK: Request/GPSK-1");
 
-	if (os_get_random(data->rand_server, EAP_GPSK_RAND_LEN)) {
+	if (random_get_bytes(data->rand_server, EAP_GPSK_RAND_LEN)) {
 		wpa_printf(MSG_ERROR, "EAP-GPSK: Failed to get random data");
 		eap_gpsk_state(data, FAILURE);
 		return NULL;
diff --git a/src/eap_server/eap_server_md5.c b/src/eap_server/eap_server_md5.c
index dee2dc5..d03ec53 100644
--- a/src/eap_server/eap_server_md5.c
+++ b/src/eap_server/eap_server_md5.c
@@ -15,6 +15,7 @@
 #include "includes.h"
 
 #include "common.h"
+#include "crypto/random.h"
 #include "eap_i.h"
 #include "eap_common/chap.h"
 
@@ -52,7 +53,7 @@ static struct wpabuf * eap_md5_buildReq(struct eap_sm *sm, void *priv, u8 id)
 	struct eap_md5_data *data = priv;
 	struct wpabuf *req;
 
-	if (os_get_random(data->challenge, CHALLENGE_LEN)) {
+	if (random_get_bytes(data->challenge, CHALLENGE_LEN)) {
 		wpa_printf(MSG_ERROR, "EAP-MD5: Failed to get random data");
 		data->state = FAILURE;
 		return NULL;
diff --git a/src/eap_server/eap_server_mschapv2.c b/src/eap_server/eap_server_mschapv2.c
index 39d1c6e..64120a4 100644
--- a/src/eap_server/eap_server_mschapv2.c
+++ b/src/eap_server/eap_server_mschapv2.c
@@ -16,6 +16,7 @@
 
 #include "common.h"
 #include "crypto/ms_funcs.h"
+#include "crypto/random.h"
 #include "eap_i.h"
 
 
@@ -109,7 +110,7 @@ static struct wpabuf * eap_mschapv2_build_challenge(
 	size_t ms_len;
 
 	if (!data->auth_challenge_from_tls &&
-	    os_get_random(data->auth_challenge, CHALLENGE_LEN)) {
+	    random_get_bytes(data->auth_challenge, CHALLENGE_LEN)) {
 		wpa_printf(MSG_ERROR, "EAP-MSCHAPV2: Failed to get random "
 			   "data");
 		data->state = FAILURE;
diff --git a/src/eap_server/eap_server_pax.c b/src/eap_server/eap_server_pax.c
index 1dc023b..4d64269 100644
--- a/src/eap_server/eap_server_pax.c
+++ b/src/eap_server/eap_server_pax.c
@@ -15,6 +15,7 @@
 #include "includes.h"
 
 #include "common.h"
+#include "crypto/random.h"
 #include "eap_server/eap_i.h"
 #include "eap_common/eap_pax_common.h"
 
@@ -82,7 +83,7 @@ static struct wpabuf * eap_pax_build_std_1(struct eap_sm *sm,
 
 	wpa_printf(MSG_DEBUG, "EAP-PAX: PAX_STD-1 (sending)");
 
-	if (os_get_random(data->rand.r.x, EAP_PAX_RAND_LEN)) {
+	if (random_get_bytes(data->rand.r.x, EAP_PAX_RAND_LEN)) {
 		wpa_printf(MSG_ERROR, "EAP-PAX: Failed to get random data");
 		data->state = FAILURE;
 		return NULL;
diff --git a/src/eap_server/eap_server_peap.c b/src/eap_server/eap_server_peap.c
index 674ecd2..8a7d626 100644
--- a/src/eap_server/eap_server_peap.c
+++ b/src/eap_server/eap_server_peap.c
@@ -17,6 +17,7 @@
 #include "common.h"
 #include "crypto/sha1.h"
 #include "crypto/tls.h"
+#include "crypto/random.h"
 #include "eap_i.h"
 #include "eap_tls_common.h"
 #include "eap_common/eap_tlv_common.h"
@@ -414,7 +415,7 @@ static struct wpabuf * eap_peap_build_phase2_tlv(struct eap_sm *sm,
 #endif /* EAP_SERVER_TNC */
 
 		if (eap_peap_derive_cmk(sm, data) < 0 ||
-		    os_get_random(data->binding_nonce, 32)) {
+		    random_get_bytes(data->binding_nonce, 32)) {
 			wpabuf_free(buf);
 			return NULL;
 		}
diff --git a/src/eap_server/eap_server_psk.c b/src/eap_server/eap_server_psk.c
index 4c30346..efc7a82 100644
--- a/src/eap_server/eap_server_psk.c
+++ b/src/eap_server/eap_server_psk.c
@@ -19,6 +19,7 @@
 
 #include "common.h"
 #include "crypto/aes_wrap.h"
+#include "crypto/random.h"
 #include "eap_common/eap_psk_common.h"
 #include "eap_server/eap_i.h"
 
@@ -66,7 +67,7 @@ static struct wpabuf * eap_psk_build_1(struct eap_sm *sm,
 
 	wpa_printf(MSG_DEBUG, "EAP-PSK: PSK-1 (sending)");
 
-	if (os_get_random(data->rand_s, EAP_PSK_RAND_LEN)) {
+	if (random_get_bytes(data->rand_s, EAP_PSK_RAND_LEN)) {
 		wpa_printf(MSG_ERROR, "EAP-PSK: Failed to get random data");
 		data->state = FAILURE;
 		return NULL;
diff --git a/src/eap_server/eap_server_sake.c b/src/eap_server/eap_server_sake.c
index ce4848f..a9b515f 100644
--- a/src/eap_server/eap_server_sake.c
+++ b/src/eap_server/eap_server_sake.c
@@ -15,6 +15,7 @@
 #include "includes.h"
 
 #include "common.h"
+#include "crypto/random.h"
 #include "eap_server/eap_i.h"
 #include "eap_common/eap_sake_common.h"
 
@@ -166,7 +167,7 @@ static struct wpabuf * eap_sake_build_challenge(struct eap_sm *sm,
 
 	wpa_printf(MSG_DEBUG, "EAP-SAKE: Request/Challenge");
 
-	if (os_get_random(data->rand_s, EAP_SAKE_RAND_LEN)) {
+	if (random_get_bytes(data->rand_s, EAP_SAKE_RAND_LEN)) {
 		wpa_printf(MSG_ERROR, "EAP-SAKE: Failed to get random data");
 		data->state = FAILURE;
 		return NULL;
diff --git a/src/eap_server/eap_server_sim.c b/src/eap_server/eap_server_sim.c
index 436c655..29df2ff 100644
--- a/src/eap_server/eap_server_sim.c
+++ b/src/eap_server/eap_server_sim.c
@@ -15,6 +15,7 @@
 #include "includes.h"
 
 #include "common.h"
+#include "crypto/random.h"
 #include "eap_server/eap_i.h"
 #include "eap_common/eap_sim_common.h"
 #include "eap_server/eap_sim_db.h"
@@ -232,7 +233,7 @@ static struct wpabuf * eap_sim_build_reauth(struct eap_sm *sm,
 
 	wpa_printf(MSG_DEBUG, "EAP-SIM: Generating Re-authentication");
 
-	if (os_get_random(data->nonce_s, EAP_SIM_NONCE_S_LEN))
+	if (random_get_bytes(data->nonce_s, EAP_SIM_NONCE_S_LEN))
 		return NULL;
 	wpa_hexdump_key(MSG_MSGDUMP, "EAP-SIM: NONCE_S",
 			data->nonce_s, EAP_SIM_NONCE_S_LEN);
diff --git a/src/eap_server/eap_sim_db.c b/src/eap_server/eap_sim_db.c
index aba919a..248b216 100644
--- a/src/eap_server/eap_sim_db.c
+++ b/src/eap_server/eap_sim_db.c
@@ -25,6 +25,7 @@
 #include <sys/un.h>
 
 #include "common.h"
+#include "crypto/random.h"
 #include "eap_common/eap_sim_common.h"
 #include "eap_server/eap_sim_db.h"
 #include "eloop.h"
@@ -830,7 +831,7 @@ static char * eap_sim_db_get_next(struct eap_sim_db_data *data, char prefix)
 	char *id, *pos, *end;
 	u8 buf[10];
 
-	if (os_get_random(buf, sizeof(buf)))
+	if (random_get_bytes(buf, sizeof(buf)))
 		return NULL;
 	id = os_malloc(sizeof(buf) * 2 + 2);
 	if (id == NULL)
diff --git a/src/eap_server/ikev2.c b/src/eap_server/ikev2.c
index 435ba26..9624d53 100644
--- a/src/eap_server/ikev2.c
+++ b/src/eap_server/ikev2.c
@@ -16,6 +16,7 @@
 
 #include "common.h"
 #include "crypto/dh_groups.h"
+#include "crypto/random.h"
 #include "ikev2.h"
 
 
@@ -1100,7 +1101,7 @@ static struct wpabuf * ikev2_build_sa_init(struct ikev2_initiator_data *data)
 		    data->i_spi, IKEV2_SPI_LEN);
 
 	data->i_nonce_len = IKEV2_NONCE_MIN_LEN;
-	if (os_get_random(data->i_nonce, data->i_nonce_len))
+	if (random_get_bytes(data->i_nonce, data->i_nonce_len))
 		return NULL;
 	wpa_hexdump(MSG_DEBUG, "IKEV2: Ni", data->i_nonce, data->i_nonce_len);
 
@@ -1148,7 +1149,7 @@ static struct wpabuf * ikev2_build_sa_auth(struct ikev2_initiator_data *data)
 		if (data->shared_secret == NULL)
 			return NULL;
 		data->shared_secret_len = 16;
-		if (os_get_random(data->shared_secret, 16))
+		if (random_get_bytes(data->shared_secret, 16))
 			return NULL;
 	} else {
 		os_free(data->shared_secret);