Donate to e Foundation | Murena handsets with /e/OS | Own a part of Murena! Learn more

Commit 47d84807 authored by Kevin Coffman's avatar Kevin Coffman Committed by Trond Myklebust
Browse files

gss_krb5: handle new context format from gssd 



For encryption types other than DES, gssd sends down context information
in a new format.  This new format includes the information needed to
support the new Kerberos GSS-API tokens defined in rfc4121.

Signed-off-by: default avatarKevin Coffman <kwc@citi.umich.edu>
Signed-off-by: default avatarSteve Dickson <steved@redhat.com>
Signed-off-by: default avatarTrond Myklebust <Trond.Myklebust@netapp.com>
parent 4891f2d0

include/linux/sunrpc/gss_krb5.h

+21 −2
Original line number Diff line number Diff line
@@ -72,21 +72,36 @@ struct gss_krb5_enctype { 
	u32 (*decrypt) (struct crypto_blkcipher *tfm,

			void *iv, void *in, void *out,

			int length);		/* decryption function */

	u32 (*mk_key) (struct gss_krb5_enctype *gk5e,

	u32 (*mk_key) (const struct gss_krb5_enctype *gk5e,

		       struct xdr_netobj *in,

		       struct xdr_netobj *out);	/* complete key generation */

};



/* krb5_ctx flags definitions */

#define KRB5_CTX_FLAG_INITIATOR         0x00000001

#define KRB5_CTX_FLAG_CFX               0x00000002

#define KRB5_CTX_FLAG_ACCEPTOR_SUBKEY   0x00000004



struct krb5_ctx {

	int			initiate; /* 1 = initiating, 0 = accepting */

	u32			enctype;

	u32			flags;

	const struct gss_krb5_enctype *gk5e; /* enctype-specific info */

	struct crypto_blkcipher	*enc;

	struct crypto_blkcipher	*seq;

	struct crypto_blkcipher *acceptor_enc;

	struct crypto_blkcipher *initiator_enc;

	u8			cksum[GSS_KRB5_MAX_KEYLEN];

	s32			endtime;

	u32			seq_send;

	u64			seq_send64;

	struct xdr_netobj	mech_used;

	u8			initiator_sign[GSS_KRB5_MAX_KEYLEN];

	u8			acceptor_sign[GSS_KRB5_MAX_KEYLEN];

	u8			initiator_seal[GSS_KRB5_MAX_KEYLEN];

	u8			acceptor_seal[GSS_KRB5_MAX_KEYLEN];

	u8			initiator_integ[GSS_KRB5_MAX_KEYLEN];

	u8			acceptor_integ[GSS_KRB5_MAX_KEYLEN];

};



extern spinlock_t krb5_seq_lock;
@@ -151,6 +166,10 @@ enum seal_alg { 
#define ENCTYPE_DES3_CBC_RAW    0x0006	/* DES-3 cbc mode raw */

#define ENCTYPE_DES_HMAC_SHA1   0x0008

#define ENCTYPE_DES3_CBC_SHA1   0x0010

#define ENCTYPE_AES128_CTS_HMAC_SHA1_96 0x0011

#define ENCTYPE_AES256_CTS_HMAC_SHA1_96 0x0012

#define ENCTYPE_ARCFOUR_HMAC            0x0017

#define ENCTYPE_ARCFOUR_HMAC_EXP        0x0018

#define ENCTYPE_UNKNOWN         0x01ff



/*
@@ -238,7 +257,7 @@ int 
xdr_extend_head(struct xdr_buf *buf, unsigned int base, unsigned int shiftlen);



u32

krb5_derive_key(struct gss_krb5_enctype *gk5e,

krb5_derive_key(const struct gss_krb5_enctype *gk5e,

		const struct xdr_netobj *inkey,

		struct xdr_netobj *outkey,

		const struct xdr_netobj *in_constant);

net/sunrpc/auth_gss/gss_krb5_keys.c

+1 −1
Original line number Diff line number Diff line
@@ -147,7 +147,7 @@ static void krb5_nfold(u32 inbits, const u8 *in, 
 * Taken from MIT Kerberos and modified.

 */



u32 krb5_derive_key(struct gss_krb5_enctype *gk5e,

u32 krb5_derive_key(const struct gss_krb5_enctype *gk5e,

		    const struct xdr_netobj *inkey,

		    struct xdr_netobj *outkey,

		    const struct xdr_netobj *in_constant)

net/sunrpc/auth_gss/gss_krb5_mech.c

+236 −1
Original line number Diff line number Diff line
@@ -48,6 +48,8 @@ 
# define RPCDBG_FACILITY	RPCDBG_AUTH

#endif



static struct gss_api_mech gss_kerberos_mech;	/* forward declaration */



static const struct gss_krb5_enctype supported_gss_krb5_enctypes[] = {

	/*

	 * DES (All DES enctypes are mapped to the same gss functionality)
@@ -247,6 +249,237 @@ out_err: 
	return PTR_ERR(p);

}



struct crypto_blkcipher *

context_v2_alloc_cipher(struct krb5_ctx *ctx, u8 *key)

{

	struct crypto_blkcipher *cp;



	cp = crypto_alloc_blkcipher(ctx->gk5e->encrypt_name,

					0, CRYPTO_ALG_ASYNC);

	if (IS_ERR(cp)) {

		dprintk("gss_kerberos_mech: unable to initialize "

			"crypto algorithm %s\n", ctx->gk5e->encrypt_name);

		return NULL;

	}

	if (crypto_blkcipher_setkey(cp, key, ctx->gk5e->keylength)) {

		dprintk("gss_kerberos_mech: error setting key for "

			"crypto algorithm %s\n", ctx->gk5e->encrypt_name);

		crypto_free_blkcipher(cp);

		return NULL;

	}

	return cp;

}



static inline void

set_cdata(u8 cdata[GSS_KRB5_K5CLENGTH], u32 usage, u8 seed)

{

	cdata[0] = (usage>>24)&0xff;

	cdata[1] = (usage>>16)&0xff;

	cdata[2] = (usage>>8)&0xff;

	cdata[3] = usage&0xff;

	cdata[4] = seed;

}



static int

context_derive_keys_des3(struct krb5_ctx *ctx, u8 *rawkey, u32 keylen)

{

	struct xdr_netobj c, keyin, keyout;

	u8 cdata[GSS_KRB5_K5CLENGTH];

	u32 err;



	c.len = GSS_KRB5_K5CLENGTH;

	c.data = cdata;



	keyin.data = rawkey;

	keyin.len = keylen;

	keyout.len = keylen;



	/* seq uses the raw key */

	ctx->seq = context_v2_alloc_cipher(ctx, rawkey);

	if (ctx->seq == NULL)

		goto out_err;



	ctx->enc = context_v2_alloc_cipher(ctx, rawkey);

	if (ctx->enc == NULL)

		goto out_free_seq;



	/* derive cksum */

	set_cdata(cdata, KG_USAGE_SIGN, KEY_USAGE_SEED_CHECKSUM);

	keyout.data = ctx->cksum;

	err = krb5_derive_key(ctx->gk5e, &keyin, &keyout, &c);

	if (err) {

		dprintk("%s: Error %d deriving cksum key\n",

			__func__, err);

		goto out_free_enc;

	}



	return 0;



out_free_enc:

	crypto_free_blkcipher(ctx->enc);

out_free_seq:

	crypto_free_blkcipher(ctx->seq);

out_err:

	return -EINVAL;

}



static int

context_derive_keys_new(struct krb5_ctx *ctx, u8 *rawkey, u32 keylen)

{

	struct xdr_netobj c, keyin, keyout;

	u8 cdata[GSS_KRB5_K5CLENGTH];

	u32 err;



	c.len = GSS_KRB5_K5CLENGTH;

	c.data = cdata;



	keyin.data = rawkey;

	keyin.len = keylen;

	keyout.len = keylen;



	/* initiator seal encryption */

	set_cdata(cdata, KG_USAGE_INITIATOR_SEAL, KEY_USAGE_SEED_ENCRYPTION);

	keyout.data = ctx->initiator_seal;

	err = krb5_derive_key(ctx->gk5e, &keyin, &keyout, &c);

	if (err) {

		dprintk("%s: Error %d deriving initiator_seal key\n",

			__func__, err);

		goto out_err;

	}

	ctx->initiator_enc = context_v2_alloc_cipher(ctx, ctx->initiator_seal);

	if (ctx->initiator_enc == NULL)

		goto out_err;



	/* acceptor seal encryption */

	set_cdata(cdata, KG_USAGE_ACCEPTOR_SEAL, KEY_USAGE_SEED_ENCRYPTION);

	keyout.data = ctx->acceptor_seal;

	err = krb5_derive_key(ctx->gk5e, &keyin, &keyout, &c);

	if (err) {

		dprintk("%s: Error %d deriving acceptor_seal key\n",

			__func__, err);

		goto out_free_initiator_enc;

	}

	ctx->acceptor_enc = context_v2_alloc_cipher(ctx, ctx->acceptor_seal);

	if (ctx->acceptor_enc == NULL)

		goto out_free_initiator_enc;



	/* 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);

	if (err) {

		dprintk("%s: Error %d deriving initiator_sign key\n",

			__func__, err);

		goto out_free_acceptor_enc;

	}



	/* 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);

	if (err) {

		dprintk("%s: Error %d deriving acceptor_sign key\n",

			__func__, err);

		goto out_free_acceptor_enc;

	}



	/* initiator seal integrity */

	set_cdata(cdata, KG_USAGE_INITIATOR_SEAL, KEY_USAGE_SEED_INTEGRITY);

	keyout.data = ctx->initiator_integ;

	err = krb5_derive_key(ctx->gk5e, &keyin, &keyout, &c);

	if (err) {

		dprintk("%s: Error %d deriving initiator_integ key\n",

			__func__, err);

		goto out_free_acceptor_enc;

	}



	/* acceptor seal integrity */

	set_cdata(cdata, KG_USAGE_ACCEPTOR_SEAL, KEY_USAGE_SEED_INTEGRITY);

	keyout.data = ctx->acceptor_integ;

	err = krb5_derive_key(ctx->gk5e, &keyin, &keyout, &c);

	if (err) {

		dprintk("%s: Error %d deriving acceptor_integ key\n",

			__func__, err);

		goto out_free_acceptor_enc;

	}



	return 0;



out_free_acceptor_enc:

	crypto_free_blkcipher(ctx->acceptor_enc);

out_free_initiator_enc:

	crypto_free_blkcipher(ctx->initiator_enc);

out_err:

	return -EINVAL;

}



static int

gss_import_v2_context(const void *p, const void *end, struct krb5_ctx *ctx)

{

	u8 rawkey[GSS_KRB5_MAX_KEYLEN];

	int keylen;



	p = simple_get_bytes(p, end, &ctx->flags, sizeof(ctx->flags));

	if (IS_ERR(p))

		goto out_err;

	ctx->initiate = ctx->flags & KRB5_CTX_FLAG_INITIATOR;



	p = simple_get_bytes(p, end, &ctx->endtime, sizeof(ctx->endtime));

	if (IS_ERR(p))

		goto out_err;

	p = simple_get_bytes(p, end, &ctx->seq_send64, sizeof(ctx->seq_send64));

	if (IS_ERR(p))

		goto out_err;

	/* set seq_send for use by "older" enctypes */

	ctx->seq_send = ctx->seq_send64;

	if (ctx->seq_send64 != ctx->seq_send) {

		dprintk("%s: seq_send64 %lx, seq_send %x overflow?\n", __func__,

			(long unsigned)ctx->seq_send64, ctx->seq_send);

		goto out_err;

	}

	p = simple_get_bytes(p, end, &ctx->enctype, sizeof(ctx->enctype));

	if (IS_ERR(p))

		goto out_err;

	ctx->gk5e = get_gss_krb5_enctype(ctx->enctype);

	if (ctx->gk5e == NULL) {

		dprintk("gss_kerberos_mech: unsupported krb5 enctype %u\n",

			ctx->enctype);

		p = ERR_PTR(-EINVAL);

		goto out_err;

	}

	keylen = ctx->gk5e->keylength;



	p = simple_get_bytes(p, end, rawkey, keylen);

	if (IS_ERR(p))

		goto out_err;



	if (p != end) {

		p = ERR_PTR(-EINVAL);

		goto out_err;

	}



	ctx->mech_used.data = kmemdup(gss_kerberos_mech.gm_oid.data,

				      gss_kerberos_mech.gm_oid.len, GFP_KERNEL);

	if (unlikely(ctx->mech_used.data == NULL)) {

		p = ERR_PTR(-ENOMEM);

		goto out_err;

	}

	ctx->mech_used.len = gss_kerberos_mech.gm_oid.len;



	switch (ctx->enctype) {

	case ENCTYPE_DES3_CBC_RAW:

		return context_derive_keys_des3(ctx, rawkey, keylen);

	case ENCTYPE_AES128_CTS_HMAC_SHA1_96:

	case ENCTYPE_AES256_CTS_HMAC_SHA1_96:

		return context_derive_keys_new(ctx, rawkey, keylen);

	default:

		return -EINVAL;

	}



out_err:

	return PTR_ERR(p);

}



static int

gss_import_sec_context_kerberos(const void *p, size_t len,

				struct gss_ctx *ctx_id)
@@ -262,7 +495,7 @@ gss_import_sec_context_kerberos(const void *p, size_t len, 
	if (len == 85)

		ret = gss_import_v1_context(p, end, ctx);

	else

		ret = -EINVAL;

		ret = gss_import_v2_context(p, end, ctx);



	if (ret == 0)

		ctx_id->internal_ctx_id = ctx;
@@ -279,6 +512,8 @@ gss_delete_sec_context_kerberos(void *internal_ctx) { 


	crypto_free_blkcipher(kctx->seq);

	crypto_free_blkcipher(kctx->enc);

	crypto_free_blkcipher(kctx->acceptor_enc);

	crypto_free_blkcipher(kctx->initiator_enc);

	kfree(kctx->mech_used.data);

	kfree(kctx);

}