commit 5248c47e1f51e0f34bdf78bac150f9c3599f14a2
author Harald Welte <laforge@osmocom.org> Tue May 30 11:09:17 2023 +0200
committer laforge <laforge@osmocom.org> Fri Jun 02 08:29:55 2023 +0000
tree c978d3d0f05ca2504b16f8c00193a49390d28e48
parent 08450c9ec6a2be9f58a9882e2ad0e78c61426254

libosmogsm: Add OSMO_ASSERT() to ensure correct algorithm

Let's make sure that nobody ever ends up calling the algo_impl
call-backs with data of a non-matching algorithm.  This should
never happen at all, as all normal users should go through
the auth_core.c:osmo_auth_gen_vec* API, which dispatches based
on algorithm.

Change-Id: I22b504b6cffb4999b2f14772fffcb2f6f02c198c

src/gsm/auth_comp128v1.c

diff --git a/src/gsm/auth_comp128v1.c b/src/gsm/auth_comp128v1.c
index a314dc2..ded3f8a 100644
--- a/src/gsm/auth_comp128v1.c
+++ b/src/gsm/auth_comp128v1.c
@@ -30,6 +30,7 @@
 			  struct osmo_sub_auth_data2 *aud,
 			  const uint8_t *_rand)
 {
+	OSMO_ASSERT(aud->algo == OSMO_AUTH_ALG_COMP128v1);
 	comp128v1(aud->u.gsm.ki, _rand, vec->sres, vec->kc);
 	vec->auth_types = OSMO_AUTH_TYPE_GSM;
 

src/gsm/auth_comp128v23.c

diff --git a/src/gsm/auth_comp128v23.c b/src/gsm/auth_comp128v23.c
index 697858a..f942bc0 100644
--- a/src/gsm/auth_comp128v23.c
+++ b/src/gsm/auth_comp128v23.c
@@ -32,6 +32,7 @@
 			  struct osmo_sub_auth_data2 *aud,
 			  const uint8_t *_rand)
 {
+	OSMO_ASSERT(aud->algo == OSMO_AUTH_ALG_COMP128v2);
 	comp128v2(aud->u.gsm.ki, _rand, vec->sres, vec->kc);
 	vec->auth_types = OSMO_AUTH_TYPE_GSM;
 
@@ -49,6 +50,7 @@
 			  struct osmo_sub_auth_data2 *aud,
 			  const uint8_t *_rand)
 {
+	OSMO_ASSERT(aud->algo == OSMO_AUTH_ALG_COMP128v3);
 	comp128v3(aud->u.gsm.ki, _rand, vec->sres, vec->kc);
 	vec->auth_types = OSMO_AUTH_TYPE_GSM;
 

src/gsm/auth_milenage.c

diff --git a/src/gsm/auth_milenage.c b/src/gsm/auth_milenage.c
index 36fbb06..84780c6 100644
--- a/src/gsm/auth_milenage.c
+++ b/src/gsm/auth_milenage.c
@@ -55,6 +55,8 @@
 	uint64_t seq_1;
 	int rc;
 
+	OSMO_ASSERT(aud->algo == OSMO_AUTH_ALG_MILENAGE);
+
 	opc = gen_opc_if_needed(aud, gen_opc);
 	if (!opc)
 		return -1;
@@ -150,6 +152,8 @@
 	const uint8_t *opc;
 	int rc;
 
+	OSMO_ASSERT(aud->algo == OSMO_AUTH_ALG_MILENAGE);
+
 	opc = gen_opc_if_needed(aud, gen_opc);
 
 	rc = milenage_auts(opc, aud->u.umts.k, rand_auts, auts, sqn_out);

src/gsm/auth_xor.c

diff --git a/src/gsm/auth_xor.c b/src/gsm/auth_xor.c
index 3552568..c94b02f 100644
--- a/src/gsm/auth_xor.c
+++ b/src/gsm/auth_xor.c
@@ -50,6 +50,8 @@
 	uint8_t ak[6], xmac[8];
 	int i;
 
+	OSMO_ASSERT(aud->algo == OSMO_AUTH_ALG_XOR_3G);
+
 	/* Step 1: xdout = (ki or k) ^ rand */
 	if (aud->type == OSMO_AUTH_TYPE_GSM)
 		xor(xdout, aud->u.gsm.ki, _rand, sizeof(xdout));
@@ -134,6 +136,8 @@
 	uint8_t ak[6], xmac[8];
 	uint8_t sqnms[6];
 
+	OSMO_ASSERT(aud->algo == OSMO_AUTH_ALG_XOR_3G);
+
 	/* Step 1: xdout = (ki or k) ^ rand */
 	if (aud->type == OSMO_AUTH_TYPE_GSM)
 		xor(xdout, aud->u.gsm.ki, _rand, sizeof(xdout));

src/gsm/auth_xor_2g.c

diff --git a/src/gsm/auth_xor_2g.c b/src/gsm/auth_xor_2g.c
index 1a96b4a..367c79d 100644
--- a/src/gsm/auth_xor_2g.c
+++ b/src/gsm/auth_xor_2g.c
@@ -48,6 +48,8 @@
 {
 	uint8_t res1[16];
 
+	OSMO_ASSERT(aud->algo == OSMO_AUTH_ALG_XOR_2G);
+
 	if (aud->type != OSMO_AUTH_TYPE_GSM)
 		return -ENOTSUP;