[PATCH net-next 19/23] rxrpc: Organise connection security to use a union

From: David Howells
Date: Thu Oct 01 2020 - 10:59:20 EST


Organise the security information in the rxrpc_connection struct to use a
union to allow for different data for different security classes.

Signed-off-by: David Howells <dhowells@xxxxxxxxxx>
---

net/rxrpc/ar-internal.h | 11 ++++++++---
net/rxrpc/rxkad.c | 40 ++++++++++++++++++++--------------------
2 files changed, 28 insertions(+), 23 deletions(-)

diff --git a/net/rxrpc/ar-internal.h b/net/rxrpc/ar-internal.h
index f314b7a33d37..af4dfb2a23bf 100644
--- a/net/rxrpc/ar-internal.h
+++ b/net/rxrpc/ar-internal.h
@@ -445,9 +445,15 @@ struct rxrpc_connection {
struct list_head proc_link; /* link in procfs list */
struct list_head link; /* link in master connection list */
struct sk_buff_head rx_queue; /* received conn-level packets */
+
const struct rxrpc_security *security; /* applied security module */
- struct crypto_sync_skcipher *cipher; /* encryption handle */
- struct rxrpc_crypt csum_iv; /* packet checksum base */
+ union {
+ struct {
+ struct crypto_sync_skcipher *cipher; /* encryption handle */
+ struct rxrpc_crypt csum_iv; /* packet checksum base */
+ u32 nonce; /* response re-use preventer */
+ } rxkad;
+ };
unsigned long flags;
unsigned long events;
unsigned long idle_timestamp; /* Time at which last became idle */
@@ -457,7 +463,6 @@ struct rxrpc_connection {
int debug_id; /* debug ID for printks */
atomic_t serial; /* packet serial number counter */
unsigned int hi_serial; /* highest serial number received */
- u32 security_nonce; /* response re-use preventer */
u32 service_id; /* Service ID, possibly upgraded */
u8 size_align; /* data size alignment (for security) */
u8 security_size; /* security header size */
diff --git a/net/rxrpc/rxkad.c b/net/rxrpc/rxkad.c
index 37335d887570..f3182edfcbae 100644
--- a/net/rxrpc/rxkad.c
+++ b/net/rxrpc/rxkad.c
@@ -137,7 +137,7 @@ static int rxkad_init_connection_security(struct rxrpc_connection *conn,
if (ret < 0)
goto error_ci;

- conn->cipher = ci;
+ conn->rxkad.cipher = ci;
return 0;

error_ci:
@@ -191,7 +191,7 @@ static int rxkad_prime_packet_security(struct rxrpc_connection *conn,
crypto_skcipher_encrypt(req);
skcipher_request_free(req);

- memcpy(&conn->csum_iv, tmpbuf + 2, sizeof(conn->csum_iv));
+ memcpy(&conn->rxkad.csum_iv, tmpbuf + 2, sizeof(conn->rxkad.csum_iv));
kfree(tmpbuf);
_leave(" = 0");
return 0;
@@ -203,7 +203,7 @@ static int rxkad_prime_packet_security(struct rxrpc_connection *conn,
*/
static struct skcipher_request *rxkad_get_call_crypto(struct rxrpc_call *call)
{
- struct crypto_skcipher *tfm = &call->conn->cipher->base;
+ struct crypto_skcipher *tfm = &call->conn->rxkad.cipher->base;
struct skcipher_request *cipher_req = call->cipher_req;

if (!cipher_req) {
@@ -251,7 +251,7 @@ static int rxkad_secure_packet_auth(const struct rxrpc_call *call,
memset(&iv, 0, sizeof(iv));

sg_init_one(&sg, skb->head, 8);
- skcipher_request_set_sync_tfm(req, call->conn->cipher);
+ skcipher_request_set_sync_tfm(req, call->conn->rxkad.cipher);
skcipher_request_set_callback(req, 0, NULL, NULL);
skcipher_request_set_crypt(req, &sg, &sg, 8, iv.x);
crypto_skcipher_encrypt(req);
@@ -293,7 +293,7 @@ static int rxkad_secure_packet_encrypt(const struct rxrpc_call *call,
memcpy(&iv, token->kad->session_key, sizeof(iv));

sg_init_one(&sg[0], skb->head, sizeof(rxkhdr));
- skcipher_request_set_sync_tfm(req, call->conn->cipher);
+ skcipher_request_set_sync_tfm(req, call->conn->rxkad.cipher);
skcipher_request_set_callback(req, 0, NULL, NULL);
skcipher_request_set_crypt(req, &sg[0], &sg[0], sizeof(rxkhdr), iv.x);
crypto_skcipher_encrypt(req);
@@ -341,7 +341,7 @@ static int rxkad_secure_packet(struct rxrpc_call *call,
call->debug_id, key_serial(call->conn->params.key),
sp->hdr.seq, data_size);

- if (!call->conn->cipher)
+ if (!call->conn->rxkad.cipher)
return 0;

ret = key_validate(call->conn->params.key);
@@ -353,7 +353,7 @@ static int rxkad_secure_packet(struct rxrpc_call *call,
return -ENOMEM;

/* continue encrypting from where we left off */
- memcpy(&iv, call->conn->csum_iv.x, sizeof(iv));
+ memcpy(&iv, call->conn->rxkad.csum_iv.x, sizeof(iv));

/* calculate the security checksum */
x = (call->cid & RXRPC_CHANNELMASK) << (32 - RXRPC_CIDSHIFT);
@@ -362,7 +362,7 @@ static int rxkad_secure_packet(struct rxrpc_call *call,
call->crypto_buf[1] = htonl(x);

sg_init_one(&sg, call->crypto_buf, 8);
- skcipher_request_set_sync_tfm(req, call->conn->cipher);
+ skcipher_request_set_sync_tfm(req, call->conn->rxkad.cipher);
skcipher_request_set_callback(req, 0, NULL, NULL);
skcipher_request_set_crypt(req, &sg, &sg, 8, iv.x);
crypto_skcipher_encrypt(req);
@@ -428,7 +428,7 @@ static int rxkad_verify_packet_1(struct rxrpc_call *call, struct sk_buff *skb,
/* start the decryption afresh */
memset(&iv, 0, sizeof(iv));

- skcipher_request_set_sync_tfm(req, call->conn->cipher);
+ skcipher_request_set_sync_tfm(req, call->conn->rxkad.cipher);
skcipher_request_set_callback(req, 0, NULL, NULL);
skcipher_request_set_crypt(req, sg, sg, 8, iv.x);
crypto_skcipher_decrypt(req);
@@ -520,7 +520,7 @@ static int rxkad_verify_packet_2(struct rxrpc_call *call, struct sk_buff *skb,
token = call->conn->params.key->payload.data[0];
memcpy(&iv, token->kad->session_key, sizeof(iv));

- skcipher_request_set_sync_tfm(req, call->conn->cipher);
+ skcipher_request_set_sync_tfm(req, call->conn->rxkad.cipher);
skcipher_request_set_callback(req, 0, NULL, NULL);
skcipher_request_set_crypt(req, sg, sg, len, iv.x);
crypto_skcipher_decrypt(req);
@@ -586,7 +586,7 @@ static int rxkad_verify_packet(struct rxrpc_call *call, struct sk_buff *skb,
_enter("{%d{%x}},{#%u}",
call->debug_id, key_serial(call->conn->params.key), seq);

- if (!call->conn->cipher)
+ if (!call->conn->rxkad.cipher)
return 0;

req = rxkad_get_call_crypto(call);
@@ -594,7 +594,7 @@ static int rxkad_verify_packet(struct rxrpc_call *call, struct sk_buff *skb,
return -ENOMEM;

/* continue encrypting from where we left off */
- memcpy(&iv, call->conn->csum_iv.x, sizeof(iv));
+ memcpy(&iv, call->conn->rxkad.csum_iv.x, sizeof(iv));

/* validate the security checksum */
x = (call->cid & RXRPC_CHANNELMASK) << (32 - RXRPC_CIDSHIFT);
@@ -603,7 +603,7 @@ static int rxkad_verify_packet(struct rxrpc_call *call, struct sk_buff *skb,
call->crypto_buf[1] = htonl(x);

sg_init_one(&sg, call->crypto_buf, 8);
- skcipher_request_set_sync_tfm(req, call->conn->cipher);
+ skcipher_request_set_sync_tfm(req, call->conn->rxkad.cipher);
skcipher_request_set_callback(req, 0, NULL, NULL);
skcipher_request_set_crypt(req, &sg, &sg, 8, iv.x);
crypto_skcipher_encrypt(req);
@@ -698,10 +698,10 @@ static int rxkad_issue_challenge(struct rxrpc_connection *conn)

_enter("{%d}", conn->debug_id);

- get_random_bytes(&conn->security_nonce, sizeof(conn->security_nonce));
+ get_random_bytes(&conn->rxkad.nonce, sizeof(conn->rxkad.nonce));

challenge.version = htonl(2);
- challenge.nonce = htonl(conn->security_nonce);
+ challenge.nonce = htonl(conn->rxkad.nonce);
challenge.min_level = htonl(0);
challenge.__padding = 0;

@@ -829,7 +829,7 @@ static int rxkad_encrypt_response(struct rxrpc_connection *conn,
struct rxrpc_crypt iv;
struct scatterlist sg[1];

- req = skcipher_request_alloc(&conn->cipher->base, GFP_NOFS);
+ req = skcipher_request_alloc(&conn->rxkad.cipher->base, GFP_NOFS);
if (!req)
return -ENOMEM;

@@ -838,7 +838,7 @@ static int rxkad_encrypt_response(struct rxrpc_connection *conn,

sg_init_table(sg, 1);
sg_set_buf(sg, &resp->encrypted, sizeof(resp->encrypted));
- skcipher_request_set_sync_tfm(req, conn->cipher);
+ skcipher_request_set_sync_tfm(req, conn->rxkad.cipher);
skcipher_request_set_callback(req, 0, NULL, NULL);
skcipher_request_set_crypt(req, sg, sg, sizeof(resp->encrypted), iv.x);
crypto_skcipher_encrypt(req);
@@ -1249,7 +1249,7 @@ static int rxkad_verify_response(struct rxrpc_connection *conn,

eproto = tracepoint_string("rxkad_rsp_seq");
abort_code = RXKADOUTOFSEQUENCE;
- if (ntohl(response->encrypted.inc_nonce) != conn->security_nonce + 1)
+ if (ntohl(response->encrypted.inc_nonce) != conn->rxkad.nonce + 1)
goto protocol_error_free;

eproto = tracepoint_string("rxkad_rsp_level");
@@ -1302,8 +1302,8 @@ static void rxkad_clear(struct rxrpc_connection *conn)
{
_enter("");

- if (conn->cipher)
- crypto_free_sync_skcipher(conn->cipher);
+ if (conn->rxkad.cipher)
+ crypto_free_sync_skcipher(conn->rxkad.cipher);
}

/*