@@ -102,14 +102,14 @@ struct krb5_ctx {
struct crypto_sync_skcipher *initiator_enc;
struct crypto_sync_skcipher *acceptor_enc_aux;
struct crypto_sync_skcipher *initiator_enc_aux;
+ struct crypto_ahash *acceptor_sign;
+ struct crypto_ahash *initiator_sign;
u8 Ksess[GSS_KRB5_MAX_KEYLEN]; /* session key */
u8 cksum[GSS_KRB5_MAX_KEYLEN];
atomic_t seq_send;
atomic64_t seq_send64;
time64_t endtime;
struct xdr_netobj mech_used;
- u8 initiator_sign[GSS_KRB5_MAX_KEYLEN];
- u8 acceptor_sign[GSS_KRB5_MAX_KEYLEN];
u8 initiator_integ[GSS_KRB5_MAX_KEYLEN];
u8 acceptor_integ[GSS_KRB5_MAX_KEYLEN];
};
@@ -252,7 +252,6 @@ u32
gss_unwrap_kerberos(struct gss_ctx *ctx_id, int offset, int len,
struct xdr_buf *buf);
-
u32
krb5_encrypt(struct crypto_sync_skcipher *key,
void *iv, void *in, void *out, int length);
@@ -346,6 +346,76 @@ make_checksum_v2(struct krb5_ctx *kctx, char *header, int hdrlen,
return err ? GSS_S_FAILURE : 0;
}
+/**
+ * gss_krb5_checksum - Compute the MAC for a GSS Wrap or MIC token
+ * @tfm: an initialized hash transform
+ * @header: pointer to a buffer containing the token header, or NULL
+ * @hdrlen: number of octets in @header
+ * @body: xdr_buf containing an RPC message (body.len is the message length)
+ * @body_offset: byte offset into @body to start checksumming
+ * @cksumout: OUT: a buffer to be filled in with the computed HMAC
+ *
+ * Usually expressed as H = HMAC(K, message)[1..h] .
+ *
+ * Caller provides the truncation length of the output token (h) in
+ * cksumout.len.
+ *
+ * Return values:
+ * %GSS_S_COMPLETE: Digest computed, @cksumout filled in
+ * %GSS_S_FAILURE: Call failed
+ */
+u32
+gss_krb5_checksum(struct crypto_ahash *tfm, char *header, int hdrlen,
+ const struct xdr_buf *body, int body_offset,
+ struct xdr_netobj *cksumout)
+{
+ struct ahash_request *req;
+ int err = -ENOMEM;
+ u8 *checksumdata;
+
+ checksumdata = kmalloc(crypto_ahash_digestsize(tfm), GFP_KERNEL);
+ if (!checksumdata)
+ return GSS_S_FAILURE;
+
+ req = ahash_request_alloc(tfm, GFP_KERNEL);
+ if (!req)
+ goto out_free_cksum;
+ ahash_request_set_callback(req, CRYPTO_TFM_REQ_MAY_SLEEP, NULL, NULL);
+ err = crypto_ahash_init(req);
+ if (err)
+ goto out_free_ahash;
+
+ /*
+ * Per RFC 4121 Section 4.2.4, the checksum is performed over the
+ * data body first, then over the octets in "header".
+ */
+ err = xdr_process_buf(body, body_offset, body->len - body_offset,
+ checksummer, req);
+ if (err)
+ goto out_free_ahash;
+ if (header) {
+ struct scatterlist sg[1];
+
+ sg_init_one(sg, header, hdrlen);
+ ahash_request_set_crypt(req, sg, NULL, hdrlen);
+ err = crypto_ahash_update(req);
+ if (err)
+ goto out_free_ahash;
+ }
+
+ ahash_request_set_crypt(req, NULL, checksumdata, 0);
+ err = crypto_ahash_final(req);
+ if (err)
+ goto out_free_ahash;
+ memcpy(cksumout->data, checksumdata, cksumout->len);
+
+out_free_ahash:
+ ahash_request_free(req);
+out_free_cksum:
+ kfree_sensitive(checksumdata);
+ return err ? GSS_S_FAILURE : GSS_S_COMPLETE;
+}
+
struct encryptor_desc {
u8 iv[GSS_KRB5_MAX_BLOCKSIZE];
struct skcipher_request *req;
@@ -10,4 +10,8 @@
void krb5_make_confounder(u8 *p, int conflen);
+u32 gss_krb5_checksum(struct crypto_ahash *tfm, char *header, int hdrlen,
+ const struct xdr_buf *body, int body_offset,
+ struct xdr_netobj *cksumout);
+
#endif /* _NET_SUNRPC_AUTH_GSS_KRB5_INTERNAL_H */
@@ -347,6 +347,21 @@ context_derive_keys_des3(struct krb5_ctx *ctx, gfp_t gfp_mask)
return -EINVAL;
}
+static struct crypto_ahash *
+gss_krb5_alloc_hash_v2(struct krb5_ctx *kctx, const struct xdr_netobj *key)
+{
+ struct crypto_ahash *tfm;
+
+ tfm = crypto_alloc_ahash(kctx->gk5e->cksum_name, 0, CRYPTO_ALG_ASYNC);
+ if (IS_ERR(tfm))
+ return NULL;
+ if (crypto_ahash_setkey(tfm, key->data, key->len)) {
+ crypto_free_ahash(tfm);
+ return NULL;
+ }
+ return tfm;
+}
+
static int
context_derive_keys_new(struct krb5_ctx *ctx, gfp_t gfp_mask)
{
@@ -414,23 +429,21 @@ context_derive_keys_new(struct krb5_ctx *ctx, gfp_t gfp_mask)
/* initiator sign checksum */
set_cdata(cdata, KG_USAGE_INITIATOR_SIGN, KEY_USAGE_SEED_CHECKSUM);
- keyout.data = ctx->initiator_sign;
err = krb5_derive_key(ctx->gk5e, &keyin, &keyout, &c, gfp_mask);
- if (err) {
- dprintk("%s: Error %d deriving initiator_sign key\n",
- __func__, err);
+ if (err)
+ goto out_free;
+ ctx->initiator_sign = gss_krb5_alloc_hash_v2(ctx, &keyout);
+ if (ctx->initiator_sign == NULL)
goto out_free;
- }
/* acceptor sign checksum */
set_cdata(cdata, KG_USAGE_ACCEPTOR_SIGN, KEY_USAGE_SEED_CHECKSUM);
- keyout.data = ctx->acceptor_sign;
err = krb5_derive_key(ctx->gk5e, &keyin, &keyout, &c, gfp_mask);
- if (err) {
- dprintk("%s: Error %d deriving acceptor_sign key\n",
- __func__, err);
+ if (err)
+ goto out_free;
+ ctx->acceptor_sign = gss_krb5_alloc_hash_v2(ctx, &keyout);
+ if (ctx->acceptor_sign == NULL)
goto out_free;
- }
/* initiator seal integrity */
set_cdata(cdata, KG_USAGE_INITIATOR_SEAL, KEY_USAGE_SEED_INTEGRITY);
@@ -458,6 +471,8 @@ context_derive_keys_new(struct krb5_ctx *ctx, gfp_t gfp_mask)
return ret;
out_free:
+ crypto_free_ahash(ctx->acceptor_sign);
+ crypto_free_ahash(ctx->initiator_sign);
crypto_free_sync_skcipher(ctx->acceptor_enc_aux);
crypto_free_sync_skcipher(ctx->acceptor_enc);
crypto_free_sync_skcipher(ctx->initiator_enc_aux);
@@ -581,6 +596,8 @@ gss_delete_sec_context_kerberos(void *internal_ctx) {
crypto_free_sync_skcipher(kctx->initiator_enc);
crypto_free_sync_skcipher(kctx->acceptor_enc_aux);
crypto_free_sync_skcipher(kctx->initiator_enc_aux);
+ crypto_free_ahash(kctx->acceptor_sign);
+ crypto_free_ahash(kctx->initiator_sign);
kfree(kctx->mech_used.data);
kfree(kctx);
}
@@ -65,6 +65,8 @@
#include <linux/crypto.h>
#include <linux/atomic.h>
+#include "gss_krb5_internal.h"
+
#if IS_ENABLED(CONFIG_SUNRPC_DEBUG)
# define RPCDBG_FACILITY RPCDBG_AUTH
#endif
@@ -166,14 +168,14 @@ static u32
gss_get_mic_v2(struct krb5_ctx *ctx, struct xdr_buf *text,
struct xdr_netobj *token)
{
- char cksumdata[GSS_KRB5_MAX_CKSUM_LEN];
- struct xdr_netobj cksumobj = { .len = sizeof(cksumdata),
- .data = cksumdata};
+ struct crypto_ahash *tfm = ctx->initiate ?
+ ctx->initiator_sign : ctx->acceptor_sign;
+ struct xdr_netobj cksumobj = {
+ .len = ctx->gk5e->cksumlength,
+ };
+ __be64 seq_send_be64;
void *krb5_hdr;
time64_t now;
- u8 *cksumkey;
- unsigned int cksum_usage;
- __be64 seq_send_be64;
dprintk("RPC: %s\n", __func__);
@@ -184,22 +186,12 @@ gss_get_mic_v2(struct krb5_ctx *ctx, struct xdr_buf *text,
seq_send_be64 = cpu_to_be64(atomic64_fetch_inc(&ctx->seq_send64));
memcpy(krb5_hdr + 8, (char *) &seq_send_be64, 8);
- if (ctx->initiate) {
- cksumkey = ctx->initiator_sign;
- cksum_usage = KG_USAGE_INITIATOR_SIGN;
- } else {
- cksumkey = ctx->acceptor_sign;
- cksum_usage = KG_USAGE_ACCEPTOR_SIGN;
- }
-
- if (make_checksum_v2(ctx, krb5_hdr, GSS_KRB5_TOK_HDR_LEN,
- text, 0, cksumkey, cksum_usage, &cksumobj))
+ cksumobj.data = krb5_hdr + GSS_KRB5_TOK_HDR_LEN;
+ if (gss_krb5_checksum(tfm, krb5_hdr, GSS_KRB5_TOK_HDR_LEN,
+ text, 0, &cksumobj))
return GSS_S_FAILURE;
- memcpy(krb5_hdr + GSS_KRB5_TOK_HDR_LEN, cksumobj.data, cksumobj.len);
-
now = ktime_get_real_seconds();
-
return (ctx->endtime < now) ? GSS_S_CONTEXT_EXPIRED : GSS_S_COMPLETE;
}
@@ -57,11 +57,14 @@
* WARRANTIES OF MERCHANTIBILITY AND FITNESS FOR A PARTICULAR PURPOSE.
*/
+#include <crypto/algapi.h>
#include <linux/types.h>
#include <linux/jiffies.h>
#include <linux/sunrpc/gss_krb5.h>
#include <linux/crypto.h>
+#include "gss_krb5_internal.h"
+
#if IS_ENABLED(CONFIG_SUNRPC_DEBUG)
# define RPCDBG_FACILITY RPCDBG_AUTH
#endif
@@ -146,16 +149,18 @@ static u32
gss_verify_mic_v2(struct krb5_ctx *ctx,
struct xdr_buf *message_buffer, struct xdr_netobj *read_token)
{
+ struct crypto_ahash *tfm = ctx->initiate ?
+ ctx->acceptor_sign : ctx->initiator_sign;
char cksumdata[GSS_KRB5_MAX_CKSUM_LEN];
- struct xdr_netobj cksumobj = {.len = sizeof(cksumdata),
- .data = cksumdata};
- time64_t now;
+ struct xdr_netobj cksumobj = {
+ .len = ctx->gk5e->cksumlength,
+ .data = cksumdata,
+ };
u8 *ptr = read_token->data;
- u8 *cksumkey;
+ __be16 be16_ptr;
+ time64_t now;
u8 flags;
int i;
- unsigned int cksum_usage;
- __be16 be16_ptr;
dprintk("RPC: %s\n", __func__);
@@ -177,16 +182,8 @@ gss_verify_mic_v2(struct krb5_ctx *ctx,
if (ptr[i] != 0xff)
return GSS_S_DEFECTIVE_TOKEN;
- if (ctx->initiate) {
- cksumkey = ctx->acceptor_sign;
- cksum_usage = KG_USAGE_ACCEPTOR_SIGN;
- } else {
- cksumkey = ctx->initiator_sign;
- cksum_usage = KG_USAGE_INITIATOR_SIGN;
- }
-
- if (make_checksum_v2(ctx, ptr, GSS_KRB5_TOK_HDR_LEN, message_buffer, 0,
- cksumkey, cksum_usage, &cksumobj))
+ if (gss_krb5_checksum(tfm, ptr, GSS_KRB5_TOK_HDR_LEN,
+ message_buffer, 0, &cksumobj))
return GSS_S_FAILURE;
if (memcmp(cksumobj.data, ptr + GSS_KRB5_TOK_HDR_LEN,