diff options
| -rw-r--r-- | include/linux/sunrpc/gss_krb5.h | 31 | ||||
| -rw-r--r-- | net/sunrpc/auth_gss/Makefile | 2 | ||||
| -rw-r--r-- | net/sunrpc/auth_gss/gss_krb5_keys.c | 252 | ||||
| -rw-r--r-- | net/sunrpc/auth_gss/gss_krb5_mech.c | 1 |
4 files changed, 285 insertions, 1 deletions
diff --git a/include/linux/sunrpc/gss_krb5.h b/include/linux/sunrpc/gss_krb5.h index abf26efd44ac..d31ba0304d18 100644 --- a/include/linux/sunrpc/gss_krb5.h +++ b/include/linux/sunrpc/gss_krb5.h @@ -41,6 +41,9 @@ #include <linux/sunrpc/gss_err.h> #include <linux/sunrpc/gss_asn1.h> +/* Length of constant used in key derivation */ +#define GSS_KRB5_K5CLENGTH (5) + /* Maximum key length (in bytes) for the supported crypto algorithms*/ #define GSS_KRB5_MAX_KEYLEN (32) @@ -69,6 +72,9 @@ 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, + struct xdr_netobj *in, + struct xdr_netobj *out); /* complete key generation */ }; struct krb5_ctx { @@ -148,6 +154,25 @@ enum seal_alg { #define ENCTYPE_UNKNOWN 0x01ff /* + * Constants used for key derivation + */ +/* for 3DES */ +#define KG_USAGE_SEAL (22) +#define KG_USAGE_SIGN (23) +#define KG_USAGE_SEQ (24) + +/* from rfc3961 */ +#define KEY_USAGE_SEED_CHECKSUM (0x99) +#define KEY_USAGE_SEED_ENCRYPTION (0xAA) +#define KEY_USAGE_SEED_INTEGRITY (0x55) + +/* from rfc4121 */ +#define KG_USAGE_ACCEPTOR_SEAL (22) +#define KG_USAGE_ACCEPTOR_SIGN (23) +#define KG_USAGE_INITIATOR_SEAL (24) +#define KG_USAGE_INITIATOR_SIGN (25) + +/* * This compile-time check verifies that we will not exceed the * slack space allotted by the client and server auth_gss code * before they call gss_wrap(). @@ -211,3 +236,9 @@ krb5_get_seq_num(struct crypto_blkcipher *key, int xdr_extend_head(struct xdr_buf *buf, unsigned int base, unsigned int shiftlen); + +u32 +krb5_derive_key(struct gss_krb5_enctype *gk5e, + const struct xdr_netobj *inkey, + struct xdr_netobj *outkey, + const struct xdr_netobj *in_constant); diff --git a/net/sunrpc/auth_gss/Makefile b/net/sunrpc/auth_gss/Makefile index 4de8bcf26fa7..74a231735f67 100644 --- a/net/sunrpc/auth_gss/Makefile +++ b/net/sunrpc/auth_gss/Makefile @@ -10,7 +10,7 @@ auth_rpcgss-objs := auth_gss.o gss_generic_token.o \ obj-$(CONFIG_RPCSEC_GSS_KRB5) += rpcsec_gss_krb5.o rpcsec_gss_krb5-objs := gss_krb5_mech.o gss_krb5_seal.o gss_krb5_unseal.o \ - gss_krb5_seqnum.o gss_krb5_wrap.o gss_krb5_crypto.o + gss_krb5_seqnum.o gss_krb5_wrap.o gss_krb5_crypto.o gss_krb5_keys.o obj-$(CONFIG_RPCSEC_GSS_SPKM3) += rpcsec_gss_spkm3.o diff --git a/net/sunrpc/auth_gss/gss_krb5_keys.c b/net/sunrpc/auth_gss/gss_krb5_keys.c new file mode 100644 index 000000000000..832ce901bf68 --- /dev/null +++ b/net/sunrpc/auth_gss/gss_krb5_keys.c @@ -0,0 +1,252 @@ +/* + * COPYRIGHT (c) 2008 + * The Regents of the University of Michigan + * ALL RIGHTS RESERVED + * + * Permission is granted to use, copy, create derivative works + * and redistribute this software and such derivative works + * for any purpose, so long as the name of The University of + * Michigan is not used in any advertising or publicity + * pertaining to the use of distribution of this software + * without specific, written prior authorization. If the + * above copyright notice or any other identification of the + * University of Michigan is included in any copy of any + * portion of this software, then the disclaimer below must + * also be included. + * + * THIS SOFTWARE IS PROVIDED AS IS, WITHOUT REPRESENTATION + * FROM THE UNIVERSITY OF MICHIGAN AS TO ITS FITNESS FOR ANY + * PURPOSE, AND WITHOUT WARRANTY BY THE UNIVERSITY OF + * MICHIGAN OF ANY KIND, EITHER EXPRESS OR IMPLIED, INCLUDING + * WITHOUT LIMITATION THE IMPLIED WARRANTIES OF + * MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE. THE + * REGENTS OF THE UNIVERSITY OF MICHIGAN SHALL NOT BE LIABLE + * FOR ANY DAMAGES, INCLUDING SPECIAL, INDIRECT, INCIDENTAL, OR + * CONSEQUENTIAL DAMAGES, WITH RESPECT TO ANY CLAIM ARISING + * OUT OF OR IN CONNECTION WITH THE USE OF THE SOFTWARE, EVEN + * IF IT HAS BEEN OR IS HEREAFTER ADVISED OF THE POSSIBILITY OF + * SUCH DAMAGES. + */ + +/* + * Copyright (C) 1998 by the FundsXpress, INC. + * + * All rights reserved. + * + * Export of this software from the United States of America may require + * a specific license from the United States Government. It is the + * responsibility of any person or organization contemplating export to + * obtain such a license before exporting. + * + * WITHIN THAT CONSTRAINT, permission to use, copy, modify, and + * distribute this software and its documentation for any purpose and + * without fee is hereby granted, provided that the above copyright + * notice appear in all copies and that both that copyright notice and + * this permission notice appear in supporting documentation, and that + * the name of FundsXpress. not be used in advertising or publicity pertaining + * to distribution of the software without specific, written prior + * permission. FundsXpress makes no representations about the suitability of + * this software for any purpose. It is provided "as is" without express + * or implied warranty. + * + * THIS SOFTWARE IS PROVIDED ``AS IS'' AND WITHOUT ANY EXPRESS OR + * IMPLIED WARRANTIES, INCLUDING, WITHOUT LIMITATION, THE IMPLIED + * WARRANTIES OF MERCHANTIBILITY AND FITNESS FOR A PARTICULAR PURPOSE. + */ + +#include <linux/err.h> +#include <linux/types.h> +#include <linux/crypto.h> +#include <linux/sunrpc/gss_krb5.h> +#include <linux/sunrpc/xdr.h> + +#ifdef RPC_DEBUG +# define RPCDBG_FACILITY RPCDBG_AUTH +#endif + +/* + * This is the n-fold function as described in rfc3961, sec 5.1 + * Taken from MIT Kerberos and modified. + */ + +static void krb5_nfold(u32 inbits, const u8 *in, + u32 outbits, u8 *out) +{ + int a, b, c, lcm; + int byte, i, msbit; + + /* the code below is more readable if I make these bytes + instead of bits */ + + inbits >>= 3; + outbits >>= 3; + + /* first compute lcm(n,k) */ + + a = outbits; + b = inbits; + + while (b != 0) { + c = b; + b = a%b; + a = c; + } + + lcm = outbits*inbits/a; + + /* now do the real work */ + + memset(out, 0, outbits); + byte = 0; + + /* this will end up cycling through k lcm(k,n)/k times, which + is correct */ + for (i = lcm-1; i >= 0; i--) { + /* compute the msbit in k which gets added into this byte */ + msbit = ( + /* first, start with the msbit in the first, + * unrotated byte */ + ((inbits << 3) - 1) + /* then, for each byte, shift to the right + * for each repetition */ + + (((inbits << 3) + 13) * (i/inbits)) + /* last, pick out the correct byte within + * that shifted repetition */ + + ((inbits - (i % inbits)) << 3) + ) % (inbits << 3); + + /* pull out the byte value itself */ + byte += (((in[((inbits - 1) - (msbit >> 3)) % inbits] << 8)| + (in[((inbits) - (msbit >> 3)) % inbits])) + >> ((msbit & 7) + 1)) & 0xff; + + /* do the addition */ + byte += out[i % outbits]; + out[i % outbits] = byte & 0xff; + + /* keep around the carry bit, if any */ + byte >>= 8; + + } + + /* if there's a carry bit left over, add it back in */ + if (byte) { + for (i = outbits - 1; i >= 0; i--) { + /* do the addition */ + byte += out[i]; + out[i] = byte & 0xff; + + /* keep around the carry bit, if any */ + byte >>= 8; + } + } +} + +/* + * This is the DK (derive_key) function as described in rfc3961, sec 5.1 + * Taken from MIT Kerberos and modified. + */ + +u32 krb5_derive_key(struct gss_krb5_enctype *gk5e, + const struct xdr_netobj *inkey, + struct xdr_netobj *outkey, + const struct xdr_netobj *in_constant) +{ + size_t blocksize, keybytes, keylength, n; + unsigned char *inblockdata, *outblockdata, *rawkey; + struct xdr_netobj inblock, outblock; + struct crypto_blkcipher *cipher; + u32 ret = EINVAL; + + blocksize = gk5e->blocksize; + keybytes = gk5e->keybytes; + keylength = gk5e->keylength; + + if ((inkey->len != keylength) || (outkey->len != keylength)) + goto err_return; + + cipher = crypto_alloc_blkcipher(gk5e->encrypt_name, 0, + CRYPTO_ALG_ASYNC); + if (IS_ERR(cipher)) + goto err_return; + if (crypto_blkcipher_setkey(cipher, inkey->data, inkey->len)) + goto err_return; + + /* allocate and set up buffers */ + + ret = ENOMEM; + inblockdata = kmalloc(blocksize, GFP_KERNEL); + if (inblockdata == NULL) + goto err_free_cipher; + + outblockdata = kmalloc(blocksize, GFP_KERNEL); + if (outblockdata == NULL) + goto err_free_in; + + rawkey = kmalloc(keybytes, GFP_KERNEL); + if (rawkey == NULL) + goto err_free_out; + + inblock.data = (char *) inblockdata; + inblock.len = blocksize; + + outblock.data = (char *) outblockdata; + outblock.len = blocksize; + + /* initialize the input block */ + + if (in_constant->len == inblock.len) { + memcpy(inblock.data, in_constant->data, inblock.len); + } else { + krb5_nfold(in_constant->len * 8, in_constant->data, + inblock.len * 8, inblock.data); + } + + /* loop encrypting the blocks until enough key bytes are generated */ + + n = 0; + while (n < keybytes) { + (*(gk5e->encrypt))(cipher, NULL, inblock.data, + outblock.data, inblock.len); + + if ((keybytes - n) <= outblock.len) { + memcpy(rawkey + n, outblock.data, (keybytes - n)); + break; + } + + memcpy(rawkey + n, outblock.data, outblock.len); + memcpy(inblock.data, outblock.data, outblock.len); + n += outblock.len; + } + + /* postprocess the key */ + + inblock.data = (char *) rawkey; + inblock.len = keybytes; + + BUG_ON(gk5e->mk_key == NULL); + ret = (*(gk5e->mk_key))(gk5e, &inblock, outkey); + if (ret) { + dprintk("%s: got %d from mk_key function for '%s'\n", + __func__, ret, gk5e->encrypt_name); + goto err_free_raw; + } + + /* clean memory, free resources and exit */ + + ret = 0; + +err_free_raw: + memset(rawkey, 0, keybytes); + kfree(rawkey); +err_free_out: + memset(outblockdata, 0, blocksize); + kfree(outblockdata); +err_free_in: + memset(inblockdata, 0, blocksize); + kfree(inblockdata); +err_free_cipher: + crypto_free_blkcipher(cipher); +err_return: + return ret; +} diff --git a/net/sunrpc/auth_gss/gss_krb5_mech.c b/net/sunrpc/auth_gss/gss_krb5_mech.c index 6f93f4752be4..fdf0eb2057ab 100644 --- a/net/sunrpc/auth_gss/gss_krb5_mech.c +++ b/net/sunrpc/auth_gss/gss_krb5_mech.c @@ -60,6 +60,7 @@ static const struct gss_krb5_enctype supported_gss_krb5_enctypes[] = { .cksum_name = "md5", .encrypt = krb5_encrypt, .decrypt = krb5_decrypt, + .mk_key = NULL, .signalg = SGN_ALG_DES_MAC_MD5, .sealalg = SEAL_ALG_DES, .keybytes = 7, |