RPC: clean up the RPCSEC_GSS kerberos and spkm3 context import functions

Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>

include/linux/sunrpc/gss_api.h

@@ -33,8 +33,9 @@ struct gss_ctx {
 
 /* gss-api prototypes; note that these are somewhat simplified versions of
  * the prototypes specified in RFC 2744. */
-u32 gss_import_sec_context(
-		struct xdr_netobj	*input_token,
+int gss_import_sec_context(
+		const void*		input_token,
+		size_t			bufsize,
 		struct gss_api_mech	*mech,
 		struct gss_ctx		**ctx_id);
 u32 gss_get_mic(
@@ -80,8 +81,9 @@ struct gss_api_mech {
 
 /* and must provide the following operations: */
 struct gss_api_ops {
-	u32 (*gss_import_sec_context)(
-			struct xdr_netobj	*input_token,
+	int (*gss_import_sec_context)(
+			const void		*input_token,
+			size_t			bufsize,
 			struct gss_ctx		*ctx_id);
 	u32 (*gss_get_mic)(
 			struct gss_ctx		*ctx_id,

net/sunrpc/auth_gss/auth_gss.c

@@ -272,7 +272,7 @@ gss_parse_init_downcall(struct gss_api_mech *gm, struct xdr_netobj *buf,
 		goto err_free_wire_ctx;
 	if (p != end)
 		goto err_free_wire_ctx;
-	if (gss_import_sec_context(&tmp_buf, gm, &ctx->gc_gss_ctx))
+	if (gss_import_sec_context(tmp_buf.data, tmp_buf.len, gm, &ctx->gc_gss_ctx))
 		goto err_free_wire_ctx;
 	*gc = ctx;
 	return 0;

net/sunrpc/auth_gss/gss_krb5_mech.c

@@ -48,46 +48,48 @@
 # define RPCDBG_FACILITY	RPCDBG_AUTH
 #endif
 
-static inline int
-get_bytes(char **ptr, const char *end, void *res, int len)
+static const void *
+simple_get_bytes(const void *p, const void *end, void *res, int len)
 {
-	char *p, *q;
-	p = *ptr;
-	q = p + len;
-	if (q > end || q < p)
-		return -1;
+	const void *q = (const void *)((const char *)p + len);
+	if (unlikely(q > end || q < p))
+		return ERR_PTR(-EFAULT);
 	memcpy(res, p, len);
-	*ptr = q;
-	return 0;
+	return q;
 }
 
-static inline int
-get_netobj(char **ptr, const char *end, struct xdr_netobj *res)
+static const void *
+simple_get_netobj(const void *p, const void *end, struct xdr_netobj *res)
 {
-	char *p, *q;
-	p = *ptr;
-	if (get_bytes(&p, end, &res->len, sizeof(res->len)))
-		return -1;
-	q = p + res->len;
-	if (q > end || q < p)
-		return -1;
-	if (!(res->data = kmalloc(res->len, GFP_KERNEL)))
-		return -1;
-	memcpy(res->data, p, res->len);
-	*ptr = q;
-	return 0;
+	const void *q;
+	unsigned int len;
+
+	p = simple_get_bytes(p, end, &len, sizeof(len));
+	if (IS_ERR(p))
+		return p;
+	q = (const void *)((const char *)p + len);
+	if (unlikely(q > end || q < p))
+		return ERR_PTR(-EFAULT);
+	res->data = kmalloc(len, GFP_KERNEL);
+	if (unlikely(res->data == NULL))
+		return ERR_PTR(-ENOMEM);
+	memcpy(res->data, p, len);
+	res->len = len;
+	return q;
 }
 
-static inline int
-get_key(char **p, char *end, struct crypto_tfm **res)
+static inline const void *
+get_key(const void *p, const void *end, struct crypto_tfm **res)
 {
 	struct xdr_netobj	key;
 	int			alg, alg_mode;
 	char			*alg_name;
 
-	if (get_bytes(p, end, &alg, sizeof(alg)))
+	p = simple_get_bytes(p, end, &alg, sizeof(alg));
+	if (IS_ERR(p))
 		goto out_err;
-	if ((get_netobj(p, end, &key)))
+	p = simple_get_netobj(p, end, &key);
+	if (IS_ERR(p))
 		goto out_err;
 
 	switch (alg) {
@@ -105,50 +107,63 @@ get_key(char **p, char *end, struct crypto_tfm **res)
 		goto out_err_free_tfm;
 
 	kfree(key.data);
-	return 0;
+	return p;
 
 out_err_free_tfm:
 	crypto_free_tfm(*res);
 out_err_free_key:
 	kfree(key.data);
+	p = ERR_PTR(-EINVAL);
 out_err:
-	return -1;
+	return p;
 }
 
-static u32
-gss_import_sec_context_kerberos(struct xdr_netobj *inbuf,
+static int
+gss_import_sec_context_kerberos(const void *p,
+				size_t len,
 				struct gss_ctx *ctx_id)
 {
-	char	*p = inbuf->data;
-	char	*end = inbuf->data + inbuf->len;
+	const void *end = (const void *)((const char *)p + len);
 	struct	krb5_ctx *ctx;
 
 	if (!(ctx = kmalloc(sizeof(*ctx), GFP_KERNEL)))
 		goto out_err;
 	memset(ctx, 0, sizeof(*ctx));
 
-	if (get_bytes(&p, end, &ctx->initiate, sizeof(ctx->initiate)))
+	p = simple_get_bytes(p, end, &ctx->initiate, sizeof(ctx->initiate));
+	if (IS_ERR(p))
 		goto out_err_free_ctx;
-	if (get_bytes(&p, end, &ctx->seed_init, sizeof(ctx->seed_init)))
+	p = simple_get_bytes(p, end, &ctx->seed_init, sizeof(ctx->seed_init));
+	if (IS_ERR(p))
 		goto out_err_free_ctx;
-	if (get_bytes(&p, end, ctx->seed, sizeof(ctx->seed)))
+	p = simple_get_bytes(p, end, ctx->seed, sizeof(ctx->seed));
+	if (IS_ERR(p))
 		goto out_err_free_ctx;
-	if (get_bytes(&p, end, &ctx->signalg, sizeof(ctx->signalg)))
+	p = simple_get_bytes(p, end, &ctx->signalg, sizeof(ctx->signalg));
+	if (IS_ERR(p))
 		goto out_err_free_ctx;
-	if (get_bytes(&p, end, &ctx->sealalg, sizeof(ctx->sealalg)))
+	p = simple_get_bytes(p, end, &ctx->sealalg, sizeof(ctx->sealalg));
+	if (IS_ERR(p))
 		goto out_err_free_ctx;
-	if (get_bytes(&p, end, &ctx->endtime, sizeof(ctx->endtime)))
+	p = simple_get_bytes(p, end, &ctx->endtime, sizeof(ctx->endtime));
+	if (IS_ERR(p))
 		goto out_err_free_ctx;
-	if (get_bytes(&p, end, &ctx->seq_send, sizeof(ctx->seq_send)))
+	p = simple_get_bytes(p, end, &ctx->seq_send, sizeof(ctx->seq_send));
+	if (IS_ERR(p))
 		goto out_err_free_ctx;
-	if (get_netobj(&p, end, &ctx->mech_used))
+	p = simple_get_netobj(p, end, &ctx->mech_used);
+	if (IS_ERR(p))
 		goto out_err_free_ctx;
-	if (get_key(&p, end, &ctx->enc))
+	p = get_key(p, end, &ctx->enc);
+	if (IS_ERR(p))
 		goto out_err_free_mech;
-	if (get_key(&p, end, &ctx->seq))
+	p = get_key(p, end, &ctx->seq);
+	if (IS_ERR(p))
 		goto out_err_free_key1;
-	if (p != end)
+	if (p != end) {
+		p = ERR_PTR(-EFAULT);
 		goto out_err_free_key2;
+	}
 
 	ctx_id->internal_ctx_id = ctx;
 	dprintk("RPC:      Succesfully imported new context.\n");
@@ -163,7 +178,7 @@ gss_import_sec_context_kerberos(struct xdr_netobj *inbuf,
 out_err_free_ctx:
 	kfree(ctx);
 out_err:
-	return GSS_S_FAILURE;
+	return PTR_ERR(p);
 }
 
 static void

net/sunrpc/auth_gss/gss_mech_switch.c

@@ -233,8 +233,8 @@ EXPORT_SYMBOL(gss_mech_put);
 
 /* The mech could probably be determined from the token instead, but it's just
  * as easy for now to pass it in. */
-u32
-gss_import_sec_context(struct xdr_netobj	*input_token,
+int
+gss_import_sec_context(const void *input_token, size_t bufsize,
 		       struct gss_api_mech	*mech,
 		       struct gss_ctx		**ctx_id)
 {
@@ -244,7 +244,7 @@ gss_import_sec_context(struct xdr_netobj	*input_token,
 	(*ctx_id)->mech_type = gss_mech_get(mech);
 
 	return mech->gm_ops
-		->gss_import_sec_context(input_token, *ctx_id);
+		->gss_import_sec_context(input_token, bufsize, *ctx_id);
 }
 
 /* gss_get_mic: compute a mic over message and return mic_token. */

net/sunrpc/auth_gss/gss_spkm3_mech.c

@@ -49,52 +49,51 @@
 # define RPCDBG_FACILITY	RPCDBG_AUTH
 #endif
 
-static inline int
-get_bytes(char **ptr, const char *end, void *res, int len)
+static const void *
+simple_get_bytes(const void *p, const void *end, void *res, int len)
 {
-	char *p, *q;
-	p = *ptr;
-	q = p + len;
-	if (q > end || q < p)
-		return -1;
+	const void *q = (const void *)((const char *)p + len);
+	if (unlikely(q > end || q < p))
+		return ERR_PTR(-EFAULT);
 	memcpy(res, p, len);
-	*ptr = q;
-	return 0;
+	return q;
 }
 
-static inline int
-get_netobj(char **ptr, const char *end, struct xdr_netobj *res)
+static const void *
+simple_get_netobj(const void *p, const void *end, struct xdr_netobj *res)
 {
-	char *p, *q;
-	p = *ptr;
-	if (get_bytes(&p, end, &res->len, sizeof(res->len)))
-		return -1;
-	q = p + res->len;
-	if(res->len == 0)
-		goto out_nocopy;
-	if (q > end || q < p)
-		return -1;
-	if (!(res->data = kmalloc(res->len, GFP_KERNEL)))
-		return -1;
-	memcpy(res->data, p, res->len);
-out_nocopy:
-	*ptr = q;
-	return 0;
+	const void *q;
+	unsigned int len;
+	p = simple_get_bytes(p, end, &len, sizeof(len));
+	if (IS_ERR(p))
+		return p;
+	res->len = len;
+	if (len == 0) {
+		res->data = NULL;
+		return p;
+	}
+	q = (const void *)((const char *)p + len);
+	if (unlikely(q > end || q < p))
+		return ERR_PTR(-EFAULT);
+	res->data = kmalloc(len, GFP_KERNEL);
+	if (unlikely(res->data == NULL))
+		return ERR_PTR(-ENOMEM);
+	memcpy(res->data, p, len);
+	return q;
 }
 
-static inline int
-get_key(char **p, char *end, struct crypto_tfm **res, int *resalg)
+static inline const void *
+get_key(const void *p, const void *end, struct crypto_tfm **res, int *resalg)
 {
-	struct xdr_netobj	key = {
-		.len = 0,
-		.data = NULL,
-	};
+	struct xdr_netobj	key = { 0 };
 	int			alg_mode,setkey = 0;
 	char			*alg_name;
 
-	if (get_bytes(p, end, resalg, sizeof(int)))
+	p = simple_get_bytes(p, end, resalg, sizeof(*resalg));
+	if (IS_ERR(p))
 		goto out_err;
-	if ((get_netobj(p, end, &key)))
+	p = simple_get_netobj(p, end, &key);
+	if (IS_ERR(p))
 		goto out_err;
 
 	switch (*resalg) {
@@ -111,10 +110,6 @@ get_key(char **p, char *end, struct crypto_tfm **res, int *resalg)
 			alg_mode = 0;
 			setkey = 0;
 			break;
-		case NID_cast5_cbc:
-			dprintk("RPC: SPKM3 get_key: case cast5_cbc, UNSUPPORTED \n");
-			goto out_err;
-			break;
 		default:
 			dprintk("RPC: SPKM3 get_key: unsupported algorithm %d", *resalg);
 			goto out_err_free_key;
@@ -128,69 +123,81 @@ get_key(char **p, char *end, struct crypto_tfm **res, int *resalg)
 
 	if(key.len > 0)
 		kfree(key.data);
-	return 0;
+	return p;
 
 out_err_free_tfm:
 	crypto_free_tfm(*res);
 out_err_free_key:
 	if(key.len > 0)
 		kfree(key.data);
+	p = ERR_PTR(-EINVAL);
 out_err:
-	return -1;
+	return p;
 }
 
-static u32
-gss_import_sec_context_spkm3(struct xdr_netobj *inbuf,
+static int
+gss_import_sec_context_spkm3(const void *p, size_t len,
 				struct gss_ctx *ctx_id)
 {
-	char	*p = inbuf->data;
-	char	*end = inbuf->data + inbuf->len;
+	const void *end = (const void *)((const char *)p + len);
 	struct	spkm3_ctx *ctx;
 
 	if (!(ctx = kmalloc(sizeof(*ctx), GFP_KERNEL)))
 		goto out_err;
 	memset(ctx, 0, sizeof(*ctx));
 
-	if (get_netobj(&p, end, &ctx->ctx_id))
+	p = simple_get_netobj(p, end, &ctx->ctx_id);
+	if (IS_ERR(p))
 		goto out_err_free_ctx;
 
-	if (get_bytes(&p, end, &ctx->qop, sizeof(ctx->qop)))
+	p = simple_get_bytes(p, end, &ctx->qop, sizeof(ctx->qop));
+	if (IS_ERR(p))
 		goto out_err_free_ctx_id;
 
-	if (get_netobj(&p, end, &ctx->mech_used))
+	p = simple_get_netobj(p, end, &ctx->mech_used);
+	if (IS_ERR(p))
 		goto out_err_free_mech;
 
-	if (get_bytes(&p, end, &ctx->ret_flags, sizeof(ctx->ret_flags)))
+	p = simple_get_bytes(p, end, &ctx->ret_flags, sizeof(ctx->ret_flags));
+	if (IS_ERR(p))
 		goto out_err_free_mech;
 
-	if (get_bytes(&p, end, &ctx->req_flags, sizeof(ctx->req_flags)))
+	p = simple_get_bytes(p, end, &ctx->req_flags, sizeof(ctx->req_flags));
+	if (IS_ERR(p))
 		goto out_err_free_mech;
 
-	if (get_netobj(&p, end, &ctx->share_key))
+	p = simple_get_netobj(p, end, &ctx->share_key);
+	if (IS_ERR(p))
 		goto out_err_free_s_key;
 
-	if (get_key(&p, end, &ctx->derived_conf_key, &ctx->conf_alg)) {
-		dprintk("RPC: SPKM3 confidentiality key will be NULL\n");
-	}
+	p = get_key(p, end, &ctx->derived_conf_key, &ctx->conf_alg);
+	if (IS_ERR(p))
+		goto out_err_free_s_key;
 
-	if (get_key(&p, end, &ctx->derived_integ_key, &ctx->intg_alg)) {
-		dprintk("RPC: SPKM3 integrity key will be NULL\n");
-	}
+	p = get_key(p, end, &ctx->derived_integ_key, &ctx->intg_alg);
+	if (IS_ERR(p))
+		goto out_err_free_key1;
 
-	if (get_bytes(&p, end, &ctx->owf_alg, sizeof(ctx->owf_alg)))
-		goto out_err_free_s_key;
+	p = simple_get_bytes(p, end, &ctx->keyestb_alg, sizeof(ctx->keyestb_alg));
+	if (IS_ERR(p))
+		goto out_err_free_key2;
 
-	if (get_bytes(&p, end, &ctx->owf_alg, sizeof(ctx->owf_alg)))
-		goto out_err_free_s_key;
+	p = simple_get_bytes(p, end, &ctx->owf_alg, sizeof(ctx->owf_alg));
+	if (IS_ERR(p))
+		goto out_err_free_key2;
 
 	if (p != end)
-		goto out_err_free_s_key;
+		goto out_err_free_key2;
 
 	ctx_id->internal_ctx_id = ctx;
 
 	dprintk("Succesfully imported new spkm context.\n");
 	return 0;
 
+out_err_free_key2:
+	crypto_free_tfm(ctx->derived_integ_key);
+out_err_free_key1:
+	crypto_free_tfm(ctx->derived_conf_key);
 out_err_free_s_key:
 	kfree(ctx->share_key.data);
 out_err_free_mech:
@@ -200,7 +207,7 @@ gss_import_sec_context_spkm3(struct xdr_netobj *inbuf,
 out_err_free_ctx:
 	kfree(ctx);
 out_err:
-	return GSS_S_FAILURE;
+	return PTR_ERR(p);
 }
 
 static void

net/sunrpc/auth_gss/svcauth_gss.c

@@ -381,7 +381,6 @@ static int rsc_parse(struct cache_detail *cd,
 	else {
 		int N, i;
 		struct gss_api_mech *gm;
-		struct xdr_netobj tmp_buf;
 
 		/* gid */
 		if (get_int(&mesg, &rsci.cred.cr_gid))
@@ -420,9 +419,7 @@ static int rsc_parse(struct cache_detail *cd,
 			gss_mech_put(gm);
 			goto out;
 		}
-		tmp_buf.len = len;
-		tmp_buf.data = buf;
-		if (gss_import_sec_context(&tmp_buf, gm, &rsci.mechctx)) {
+		if (gss_import_sec_context(buf, len, gm, &rsci.mechctx)) {
 			gss_mech_put(gm);
 			goto out;
 		}