diff options
Diffstat (limited to 'drivers/staging/lustre/lustre/ptlrpc/gss/gss_krb5_mech.c')
| -rw-r--r-- | drivers/staging/lustre/lustre/ptlrpc/gss/gss_krb5_mech.c | 1786 |
1 files changed, 1786 insertions, 0 deletions
diff --git a/drivers/staging/lustre/lustre/ptlrpc/gss/gss_krb5_mech.c b/drivers/staging/lustre/lustre/ptlrpc/gss/gss_krb5_mech.c new file mode 100644 index 000000000000..4b28931bbc96 --- /dev/null +++ b/drivers/staging/lustre/lustre/ptlrpc/gss/gss_krb5_mech.c @@ -0,0 +1,1786 @@ +/* + * Modifications for Lustre + * + * Copyright (c) 2007, 2010, Oracle and/or its affiliates. All rights reserved. + * + * Copyright (c) 2011, 2012, Intel Corporation. + * + * Author: Eric Mei <ericm@clusterfs.com> + */ + +/* + * linux/net/sunrpc/gss_krb5_mech.c + * linux/net/sunrpc/gss_krb5_crypto.c + * linux/net/sunrpc/gss_krb5_seal.c + * linux/net/sunrpc/gss_krb5_seqnum.c + * linux/net/sunrpc/gss_krb5_unseal.c + * + * Copyright (c) 2001 The Regents of the University of Michigan. + * All rights reserved. + * + * Andy Adamson <andros@umich.edu> + * J. Bruce Fields <bfields@umich.edu> + * + * Redistribution and use in source and binary forms, with or without + * modification, are permitted provided that the following conditions + * are met: + * + * 1. Redistributions of source code must retain the above copyright + * notice, this list of conditions and the following disclaimer. + * 2. Redistributions in binary form must reproduce the above copyright + * notice, this list of conditions and the following disclaimer in the + * documentation and/or other materials provided with the distribution. + * 3. Neither the name of the University nor the names of its + * contributors may be used to endorse or promote products derived + * from this software without specific prior written permission. + * + * THIS SOFTWARE IS PROVIDED ``AS IS'' AND ANY EXPRESS OR IMPLIED + * WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF + * MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE + * DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE + * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR + * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF + * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR + * BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF + * LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING + * NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS + * SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. + * + */ + +#define DEBUG_SUBSYSTEM S_SEC +#include <linux/init.h> +#include <linux/module.h> +#include <linux/slab.h> +#include <linux/crypto.h> +#include <linux/mutex.h> + +#include <obd.h> +#include <obd_class.h> +#include <obd_support.h> +#include <lustre/lustre_idl.h> +#include <lustre_net.h> +#include <lustre_import.h> +#include <lustre_sec.h> + +#include "gss_err.h" +#include "gss_internal.h" +#include "gss_api.h" +#include "gss_asn1.h" +#include "gss_krb5.h" + +static spinlock_t krb5_seq_lock; + +struct krb5_enctype { + char *ke_dispname; + char *ke_enc_name; /* linux tfm name */ + char *ke_hash_name; /* linux tfm name */ + int ke_enc_mode; /* linux tfm mode */ + int ke_hash_size; /* checksum size */ + int ke_conf_size; /* confounder size */ + unsigned int ke_hash_hmac:1; /* is hmac? */ +}; + +/* + * NOTE: for aes128-cts and aes256-cts, MIT implementation use CTS encryption. + * but currently we simply CBC with padding, because linux doesn't support CTS + * yet. this need to be fixed in the future. + */ +static struct krb5_enctype enctypes[] = { + [ENCTYPE_DES_CBC_RAW] = { /* des-cbc-md5 */ + "des-cbc-md5", + "cbc(des)", + "md5", + 0, + 16, + 8, + 0, + }, + [ENCTYPE_DES3_CBC_RAW] = { /* des3-hmac-sha1 */ + "des3-hmac-sha1", + "cbc(des3_ede)", + "hmac(sha1)", + 0, + 20, + 8, + 1, + }, + [ENCTYPE_AES128_CTS_HMAC_SHA1_96] = { /* aes128-cts */ + "aes128-cts-hmac-sha1-96", + "cbc(aes)", + "hmac(sha1)", + 0, + 12, + 16, + 1, + }, + [ENCTYPE_AES256_CTS_HMAC_SHA1_96] = { /* aes256-cts */ + "aes256-cts-hmac-sha1-96", + "cbc(aes)", + "hmac(sha1)", + 0, + 12, + 16, + 1, + }, + [ENCTYPE_ARCFOUR_HMAC] = { /* arcfour-hmac-md5 */ + "arcfour-hmac-md5", + "ecb(arc4)", + "hmac(md5)", + 0, + 16, + 8, + 1, + }, +}; + +#define MAX_ENCTYPES sizeof(enctypes)/sizeof(struct krb5_enctype) + +static const char * enctype2str(__u32 enctype) +{ + if (enctype < MAX_ENCTYPES && enctypes[enctype].ke_dispname) + return enctypes[enctype].ke_dispname; + + return "unknown"; +} + +static +int keyblock_init(struct krb5_keyblock *kb, char *alg_name, int alg_mode) +{ + kb->kb_tfm = ll_crypto_alloc_blkcipher(alg_name, alg_mode, 0); + if (IS_ERR(kb->kb_tfm)) { + CERROR("failed to alloc tfm: %s, mode %d\n", + alg_name, alg_mode); + return -1; + } + + if (ll_crypto_blkcipher_setkey(kb->kb_tfm, kb->kb_key.data, kb->kb_key.len)) { + CERROR("failed to set %s key, len %d\n", + alg_name, kb->kb_key.len); + return -1; + } + + return 0; +} + +static +int krb5_init_keys(struct krb5_ctx *kctx) +{ + struct krb5_enctype *ke; + + if (kctx->kc_enctype >= MAX_ENCTYPES || + enctypes[kctx->kc_enctype].ke_hash_size == 0) { + CERROR("unsupported enctype %x\n", kctx->kc_enctype); + return -1; + } + + ke = &enctypes[kctx->kc_enctype]; + + /* tfm arc4 is stateful, user should alloc-use-free by his own */ + if (kctx->kc_enctype != ENCTYPE_ARCFOUR_HMAC && + keyblock_init(&kctx->kc_keye, ke->ke_enc_name, ke->ke_enc_mode)) + return -1; + + /* tfm hmac is stateful, user should alloc-use-free by his own */ + if (ke->ke_hash_hmac == 0 && + keyblock_init(&kctx->kc_keyi, ke->ke_enc_name, ke->ke_enc_mode)) + return -1; + if (ke->ke_hash_hmac == 0 && + keyblock_init(&kctx->kc_keyc, ke->ke_enc_name, ke->ke_enc_mode)) + return -1; + + return 0; +} + +static +void keyblock_free(struct krb5_keyblock *kb) +{ + rawobj_free(&kb->kb_key); + if (kb->kb_tfm) + ll_crypto_free_blkcipher(kb->kb_tfm); +} + +static +int keyblock_dup(struct krb5_keyblock *new, struct krb5_keyblock *kb) +{ + return rawobj_dup(&new->kb_key, &kb->kb_key); +} + +static +int get_bytes(char **ptr, const char *end, void *res, int len) +{ + char *p, *q; + p = *ptr; + q = p + len; + if (q > end || q < p) + return -1; + memcpy(res, p, len); + *ptr = q; + return 0; +} + +static +int get_rawobj(char **ptr, const char *end, rawobj_t *res) +{ + char *p, *q; + __u32 len; + + p = *ptr; + if (get_bytes(&p, end, &len, sizeof(len))) + return -1; + + q = p + len; + if (q > end || q < p) + return -1; + + OBD_ALLOC_LARGE(res->data, len); + if (!res->data) + return -1; + + res->len = len; + memcpy(res->data, p, len); + *ptr = q; + return 0; +} + +static +int get_keyblock(char **ptr, const char *end, + struct krb5_keyblock *kb, __u32 keysize) +{ + char *buf; + + OBD_ALLOC_LARGE(buf, keysize); + if (buf == NULL) + return -1; + + if (get_bytes(ptr, end, buf, keysize)) { + OBD_FREE_LARGE(buf, keysize); + return -1; + } + + kb->kb_key.len = keysize; + kb->kb_key.data = buf; + return 0; +} + +static +void delete_context_kerberos(struct krb5_ctx *kctx) +{ + rawobj_free(&kctx->kc_mech_used); + + keyblock_free(&kctx->kc_keye); + keyblock_free(&kctx->kc_keyi); + keyblock_free(&kctx->kc_keyc); +} + +static +__u32 import_context_rfc1964(struct krb5_ctx *kctx, char *p, char *end) +{ + unsigned int tmp_uint, keysize; + + /* seed_init flag */ + if (get_bytes(&p, end, &tmp_uint, sizeof(tmp_uint))) + goto out_err; + kctx->kc_seed_init = (tmp_uint != 0); + + /* seed */ + if (get_bytes(&p, end, kctx->kc_seed, sizeof(kctx->kc_seed))) + goto out_err; + + /* sign/seal algorithm, not really used now */ + if (get_bytes(&p, end, &tmp_uint, sizeof(tmp_uint)) || + get_bytes(&p, end, &tmp_uint, sizeof(tmp_uint))) + goto out_err; + + /* end time */ + if (get_bytes(&p, end, &kctx->kc_endtime, sizeof(kctx->kc_endtime))) + goto out_err; + + /* seq send */ + if (get_bytes(&p, end, &tmp_uint, sizeof(tmp_uint))) + goto out_err; + kctx->kc_seq_send = tmp_uint; + + /* mech oid */ + if (get_rawobj(&p, end, &kctx->kc_mech_used)) + goto out_err; + + /* old style enc/seq keys in format: + * - enctype (u32) + * - keysize (u32) + * - keydata + * we decompose them to fit into the new context + */ + + /* enc key */ + if (get_bytes(&p, end, &kctx->kc_enctype, sizeof(kctx->kc_enctype))) + goto out_err; + + if (get_bytes(&p, end, &keysize, sizeof(keysize))) + goto out_err; + + if (get_keyblock(&p, end, &kctx->kc_keye, keysize)) + goto out_err; + + /* seq key */ + if (get_bytes(&p, end, &tmp_uint, sizeof(tmp_uint)) || + tmp_uint != kctx->kc_enctype) + goto out_err; + + if (get_bytes(&p, end, &tmp_uint, sizeof(tmp_uint)) || + tmp_uint != keysize) + goto out_err; + + if (get_keyblock(&p, end, &kctx->kc_keyc, keysize)) + goto out_err; + + /* old style fallback */ + if (keyblock_dup(&kctx->kc_keyi, &kctx->kc_keyc)) + goto out_err; + + if (p != end) + goto out_err; + + CDEBUG(D_SEC, "succesfully imported rfc1964 context\n"); + return 0; +out_err: + return GSS_S_FAILURE; +} + +/* Flags for version 2 context flags */ +#define KRB5_CTX_FLAG_INITIATOR 0x00000001 +#define KRB5_CTX_FLAG_CFX 0x00000002 +#define KRB5_CTX_FLAG_ACCEPTOR_SUBKEY 0x00000004 + +static +__u32 import_context_rfc4121(struct krb5_ctx *kctx, char *p, char *end) +{ + unsigned int tmp_uint, keysize; + + /* end time */ + if (get_bytes(&p, end, &kctx->kc_endtime, sizeof(kctx->kc_endtime))) + goto out_err; + + /* flags */ + if (get_bytes(&p, end, &tmp_uint, sizeof(tmp_uint))) + goto out_err; + + if (tmp_uint & KRB5_CTX_FLAG_INITIATOR) + kctx->kc_initiate = 1; + if (tmp_uint & KRB5_CTX_FLAG_CFX) + kctx->kc_cfx = 1; + if (tmp_uint & KRB5_CTX_FLAG_ACCEPTOR_SUBKEY) + kctx->kc_have_acceptor_subkey = 1; + + /* seq send */ + if (get_bytes(&p, end, &kctx->kc_seq_send, sizeof(kctx->kc_seq_send))) + goto out_err; + + /* enctype */ + if (get_bytes(&p, end, &kctx->kc_enctype, sizeof(kctx->kc_enctype))) + goto out_err; + + /* size of each key */ + if (get_bytes(&p, end, &keysize, sizeof(keysize))) + goto out_err; + + /* number of keys - should always be 3 */ + if (get_bytes(&p, end, &tmp_uint, sizeof(tmp_uint))) + goto out_err; + + if (tmp_uint != 3) { + CERROR("Invalid number of keys: %u\n", tmp_uint); + goto out_err; + } + + /* ke */ + if (get_keyblock(&p, end, &kctx->kc_keye, keysize)) + goto out_err; + /* ki */ + if (get_keyblock(&p, end, &kctx->kc_keyi, keysize)) + goto out_err; + /* ki */ + if (get_keyblock(&p, end, &kctx->kc_keyc, keysize)) + goto out_err; + + CDEBUG(D_SEC, "succesfully imported v2 context\n"); + return 0; +out_err: + return GSS_S_FAILURE; +} + +/* + * The whole purpose here is trying to keep user level gss context parsing + * from nfs-utils unchanged as possible as we can, they are not quite mature + * yet, and many stuff still not clear, like heimdal etc. + */ +static +__u32 gss_import_sec_context_kerberos(rawobj_t *inbuf, + struct gss_ctx *gctx) +{ + struct krb5_ctx *kctx; + char *p = (char *) inbuf->data; + char *end = (char *) (inbuf->data + inbuf->len); + unsigned int tmp_uint, rc; + + if (get_bytes(&p, end, &tmp_uint, sizeof(tmp_uint))) { + CERROR("Fail to read version\n"); + return GSS_S_FAILURE; + } + + /* only support 0, 1 for the moment */ + if (tmp_uint > 2) { + CERROR("Invalid version %u\n", tmp_uint); + return GSS_S_FAILURE; + } + + OBD_ALLOC_PTR(kctx); + if (!kctx) + return GSS_S_FAILURE; + + if (tmp_uint == 0 || tmp_uint == 1) { + kctx->kc_initiate = tmp_uint; + rc = import_context_rfc1964(kctx, p, end); + } else { + rc = import_context_rfc4121(kctx, p, end); + } + + if (rc == 0) + rc = krb5_init_keys(kctx); + + if (rc) { + delete_context_kerberos(kctx); + OBD_FREE_PTR(kctx); + + return GSS_S_FAILURE; + } + + gctx->internal_ctx_id = kctx; + return GSS_S_COMPLETE; +} + +static +__u32 gss_copy_reverse_context_kerberos(struct gss_ctx *gctx, + struct gss_ctx *gctx_new) +{ + struct krb5_ctx *kctx = gctx->internal_ctx_id; + struct krb5_ctx *knew; + + OBD_ALLOC_PTR(knew); + if (!knew) + return GSS_S_FAILURE; + + knew->kc_initiate = kctx->kc_initiate ? 0 : 1; + knew->kc_cfx = kctx->kc_cfx; + knew->kc_seed_init = kctx->kc_seed_init; + knew->kc_have_acceptor_subkey = kctx->kc_have_acceptor_subkey; + knew->kc_endtime = kctx->kc_endtime; + + memcpy(knew->kc_seed, kctx->kc_seed, sizeof(kctx->kc_seed)); + knew->kc_seq_send = kctx->kc_seq_recv; + knew->kc_seq_recv = kctx->kc_seq_send; + knew->kc_enctype = kctx->kc_enctype; + + if (rawobj_dup(&knew->kc_mech_used, &kctx->kc_mech_used)) + goto out_err; + + if (keyblock_dup(&knew->kc_keye, &kctx->kc_keye)) + goto out_err; + if (keyblock_dup(&knew->kc_keyi, &kctx->kc_keyi)) + goto out_err; + if (keyblock_dup(&knew->kc_keyc, &kctx->kc_keyc)) + goto out_err; + if (krb5_init_keys(knew)) + goto out_err; + + gctx_new->internal_ctx_id = knew; + CDEBUG(D_SEC, "succesfully copied reverse context\n"); + return GSS_S_COMPLETE; + +out_err: + delete_context_kerberos(knew); + OBD_FREE_PTR(knew); + return GSS_S_FAILURE; +} + +static +__u32 gss_inquire_context_kerberos(struct gss_ctx *gctx, + unsigned long *endtime) +{ + struct krb5_ctx *kctx = gctx->internal_ctx_id; + + *endtime = (unsigned long) ((__u32) kctx->kc_endtime); + return GSS_S_COMPLETE; +} + +static +void gss_delete_sec_context_kerberos(void *internal_ctx) +{ + struct krb5_ctx *kctx = internal_ctx; + + delete_context_kerberos(kctx); + OBD_FREE_PTR(kctx); +} + +static +void buf_to_sg(struct scatterlist *sg, void *ptr, int len) +{ + sg_set_buf(sg, ptr, len); +} + +static +__u32 krb5_encrypt(struct ll_crypto_cipher *tfm, + int decrypt, + void * iv, + void * in, + void * out, + int length) +{ + struct blkcipher_desc desc; + struct scatterlist sg; + __u8 local_iv[16] = {0}; + __u32 ret = -EINVAL; + + LASSERT(tfm); + desc.tfm = tfm; + desc.info = local_iv; + desc.flags= 0; + + if (length % ll_crypto_blkcipher_blocksize(tfm) != 0) { + CERROR("output length %d mismatch blocksize %d\n", + length, ll_crypto_blkcipher_blocksize(tfm)); + goto out; + } + + if (ll_crypto_blkcipher_ivsize(tfm) > 16) { + CERROR("iv size too large %d\n", ll_crypto_blkcipher_ivsize(tfm)); + goto out; + } + + if (iv) + memcpy(local_iv, iv, ll_crypto_blkcipher_ivsize(tfm)); + + memcpy(out, in, length); + buf_to_sg(&sg, out, length); + + if (decrypt) + ret = ll_crypto_blkcipher_decrypt_iv(&desc, &sg, &sg, length); + else + ret = ll_crypto_blkcipher_encrypt_iv(&desc, &sg, &sg, length); + +out: + return(ret); +} + + +static inline +int krb5_digest_hmac(struct ll_crypto_hash *tfm, + rawobj_t *key, + struct krb5_header *khdr, + int msgcnt, rawobj_t *msgs, + int iovcnt, lnet_kiov_t *iovs, + rawobj_t *cksum) +{ + struct hash_desc desc; + struct scatterlist sg[1]; + int i; + + ll_crypto_hash_setkey(tfm, key->data, key->len); + desc.tfm = tfm; + desc.flags= 0; + + ll_crypto_hash_init(&desc); + + for (i = 0; i < msgcnt; i++) { + if (msgs[i].len == 0) + continue; + buf_to_sg(sg, (char *) msgs[i].data, msgs[i].len); + ll_crypto_hash_update(&desc, sg, msgs[i].len); + } + + for (i = 0; i < iovcnt; i++) { + if (iovs[i].kiov_len == 0) + continue; + + sg_set_page(&sg[0], iovs[i].kiov_page, iovs[i].kiov_len, + iovs[i].kiov_offset); + ll_crypto_hash_update(&desc, sg, iovs[i].kiov_len); + } + + if (khdr) { + buf_to_sg(sg, (char *) khdr, sizeof(*khdr)); + ll_crypto_hash_update(&desc, sg, sizeof(*khdr)); + } + + return ll_crypto_hash_final(&desc, cksum->data); +} + + +static inline +int krb5_digest_norm(struct ll_crypto_hash *tfm, + struct krb5_keyblock *kb, + struct krb5_header *khdr, + int msgcnt, rawobj_t *msgs, + int iovcnt, lnet_kiov_t *iovs, + rawobj_t *cksum) +{ + struct hash_desc desc; + struct scatterlist sg[1]; + int i; + + LASSERT(kb->kb_tfm); + desc.tfm = tfm; + desc.flags= 0; + + ll_crypto_hash_init(&desc); + + for (i = 0; i < msgcnt; i++) { + if (msgs[i].len == 0) + continue; + buf_to_sg(sg, (char *) msgs[i].data, msgs[i].len); + ll_crypto_hash_update(&desc, sg, msgs[i].len); + } + + for (i = 0; i < iovcnt; i++) { + if (iovs[i].kiov_len == 0) + continue; + + sg_set_page(&sg[0], iovs[i].kiov_page, iovs[i].kiov_len, + iovs[i].kiov_offset); + ll_crypto_hash_update(&desc, sg, iovs[i].kiov_len); + } + + if (khdr) { + buf_to_sg(sg, (char *) khdr, sizeof(*khdr)); + ll_crypto_hash_update(&desc, sg, sizeof(*khdr)); + } + + ll_crypto_hash_final(&desc, cksum->data); + + return krb5_encrypt(kb->kb_tfm, 0, NULL, cksum->data, + cksum->data, cksum->len); +} + +/* + * compute (keyed/keyless) checksum against the plain text which appended + * with krb5 wire token header. + */ +static +__s32 krb5_make_checksum(__u32 enctype, + struct krb5_keyblock *kb, + struct krb5_header *khdr, + int msgcnt, rawobj_t *msgs, + int iovcnt, lnet_kiov_t *iovs, + rawobj_t *cksum) +{ + struct krb5_enctype *ke = &enctypes[enctype]; + struct ll_crypto_hash *tfm; + __u32 code = GSS_S_FAILURE; + int rc; + + if (!(tfm = ll_crypto_alloc_hash(ke->ke_hash_name, 0, 0))) { + CERROR("failed to alloc TFM: %s\n", ke->ke_hash_name); + return GSS_S_FAILURE; + } + + cksum->len = ll_crypto_hash_digestsize(tfm); + OBD_ALLOC_LARGE(cksum->data, cksum->len); + if (!cksum->data) { + cksum->len = 0; + goto out_tfm; + } + + if (ke->ke_hash_hmac) + rc = krb5_digest_hmac(tfm, &kb->kb_key, + khdr, msgcnt, msgs, iovcnt, iovs, cksum); + else + rc = krb5_digest_norm(tfm, kb, + khdr, msgcnt, msgs, iovcnt, iovs, cksum); + + if (rc == 0) + code = GSS_S_COMPLETE; +out_tfm: + ll_crypto_free_hash(tfm); + return code; +} + +static void fill_krb5_header(struct krb5_ctx *kctx, + struct krb5_header *khdr, + int privacy) +{ + unsigned char acceptor_flag; + + acceptor_flag = kctx->kc_initiate ? 0 : FLAG_SENDER_IS_ACCEPTOR; + + if (privacy) { + khdr->kh_tok_id = cpu_to_be16(KG_TOK_WRAP_MSG); + khdr->kh_flags = acceptor_flag | FLAG_WRAP_CONFIDENTIAL; + khdr->kh_ec = cpu_to_be16(0); + khdr->kh_rrc = cpu_to_be16(0); + } else { + khdr->kh_tok_id = cpu_to_be16(KG_TOK_MIC_MSG); + khdr->kh_flags = acceptor_flag; + khdr->kh_ec = cpu_to_be16(0xffff); + khdr->kh_rrc = cpu_to_be16(0xffff); + } + + khdr->kh_filler = 0xff; + spin_lock(&krb5_seq_lock); + khdr->kh_seq = cpu_to_be64(kctx->kc_seq_send++); + spin_unlock(&krb5_seq_lock); +} + +static __u32 verify_krb5_header(struct krb5_ctx *kctx, + struct krb5_header *khdr, + int privacy) +{ + unsigned char acceptor_flag; + __u16 tok_id, ec_rrc; + + acceptor_flag = kctx->kc_initiate ? FLAG_SENDER_IS_ACCEPTOR : 0; + + if (privacy) { + tok_id = KG_TOK_WRAP_MSG; + ec_rrc = 0x0; + } else { + tok_id = KG_TOK_MIC_MSG; + ec_rrc = 0xffff; + } + + /* sanity checks */ + if (be16_to_cpu(khdr->kh_tok_id) != tok_id) { + CERROR("bad token id\n"); + return GSS_S_DEFECTIVE_TOKEN; + } + if ((khdr->kh_flags & FLAG_SENDER_IS_ACCEPTOR) != acceptor_flag) { + CERROR("bad direction flag\n"); + return GSS_S_BAD_SIG; + } + if (privacy && (khdr->kh_flags & FLAG_WRAP_CONFIDENTIAL) == 0) { + CERROR("missing confidential flag\n"); + return GSS_S_BAD_SIG; + } + if (khdr->kh_filler != 0xff) { + CERROR("bad filler\n"); + return GSS_S_DEFECTIVE_TOKEN; + } + if (be16_to_cpu(khdr->kh_ec) != ec_rrc || + be16_to_cpu(khdr->kh_rrc) != ec_rrc) { + CERROR("bad EC or RRC\n"); + return GSS_S_DEFECTIVE_TOKEN; + } + return GSS_S_COMPLETE; +} + +static +__u32 gss_get_mic_kerberos(struct gss_ctx *gctx, + int msgcnt, + rawobj_t *msgs, + int iovcnt, + lnet_kiov_t *iovs, + rawobj_t *token) +{ + struct krb5_ctx *kctx = gctx->internal_ctx_id; + struct krb5_enctype *ke = &enctypes[kctx->kc_enctype]; + struct krb5_header *khdr; + rawobj_t cksum = RAWOBJ_EMPTY; + + /* fill krb5 header */ + LASSERT(token->len >= sizeof(*khdr)); + khdr = (struct krb5_header *) token->data; + fill_krb5_header(kctx, khdr, 0); + + /* checksum */ + if (krb5_make_checksum(kctx->kc_enctype, &kctx->kc_keyc, + khdr, msgcnt, msgs, iovcnt, iovs, &cksum)) + return GSS_S_FAILURE; + + LASSERT(cksum.len >= ke->ke_hash_size); + LASSERT(token->len >= sizeof(*khdr) + ke->ke_hash_size); + memcpy(khdr + 1, cksum.data + cksum.len - ke->ke_hash_size, + ke->ke_hash_size); + + token->len = sizeof(*khdr) + ke->ke_hash_size; + rawobj_free(&cksum); + return GSS_S_COMPLETE; +} + +static +__u32 gss_verify_mic_kerberos(struct gss_ctx *gctx, + int msgcnt, + rawobj_t *msgs, + int iovcnt, + lnet_kiov_t *iovs, + rawobj_t *token) +{ + struct krb5_ctx *kctx = gctx->internal_ctx_id; + struct krb5_enctype *ke = &enctypes[kctx->kc_enctype]; + struct krb5_header *khdr; + rawobj_t cksum = RAWOBJ_EMPTY; + __u32 major; + + if (token->len < sizeof(*khdr)) { + CERROR("short signature: %u\n", token->len); + return GSS_S_DEFECTIVE_TOKEN; + } + + khdr = (struct krb5_header *) token->data; + + major = verify_krb5_header(kctx, khdr, 0); + if (major != GSS_S_COMPLETE) { + CERROR("bad krb5 header\n"); + return major; + } + + if (token->len < sizeof(*khdr) + ke->ke_hash_size) { + CERROR("short signature: %u, require %d\n", + token->len, (int) sizeof(*khdr) + ke->ke_hash_size); + return GSS_S_FAILURE; + } + + if (krb5_make_checksum(kctx->kc_enctype, &kctx->kc_keyc, + khdr, msgcnt, msgs, iovcnt, iovs, &cksum)) { + CERROR("failed to make checksum\n"); + return GSS_S_FAILURE; + } + + LASSERT(cksum.len >= ke->ke_hash_size); + if (memcmp(khdr + 1, cksum.data + cksum.len - ke->ke_hash_size, + ke->ke_hash_size)) { + CERROR("checksum mismatch\n"); + rawobj_free(&cksum); + return GSS_S_BAD_SIG; + } + + rawobj_free(&cksum); + return GSS_S_COMPLETE; +} + +static +int add_padding(rawobj_t *msg, int msg_buflen, int blocksize) +{ + int padding; + + padding = (blocksize - (msg->len & (blocksize - 1))) & + (blocksize - 1); + if (!padding) + return 0; + + if (msg->len + padding > msg_buflen) { + CERROR("bufsize %u too small: datalen %u, padding %u\n", + msg_buflen, msg->len, padding); + return -EINVAL; + } + + memset(msg->data + msg->len, padding, padding); + msg->len += padding; + return 0; +} + +static +int krb5_encrypt_rawobjs(struct ll_crypto_cipher *tfm, + int mode_ecb, + int inobj_cnt, + rawobj_t *inobjs, + rawobj_t *outobj, + int enc) +{ + struct blkcipher_desc desc; + struct scatterlist src, dst; + __u8 local_iv[16] = {0}, *buf; + __u32 datalen = 0; + int i, rc; + ENTRY; + + buf = outobj->data; + desc.tfm = tfm; + desc.info = local_iv; + desc.flags = 0; + + for (i = 0; i < inobj_cnt; i++) { + LASSERT(buf + inobjs[i].len <= outobj->data + outobj->len); + + buf_to_sg(&src, inobjs[i].data, inobjs[i].len); + buf_to_sg(&dst, buf, outobj->len - datalen); + + if (mode_ecb) { + if (enc) + rc = ll_crypto_blkcipher_encrypt( + &desc, &dst, &src, src.length); + else + rc = ll_crypto_blkcipher_decrypt( + &desc, &dst, &src, src.length); + } else { + if (enc) + rc = ll_crypto_blkcipher_encrypt_iv( + &desc, &dst, &src, src.length); + else + rc = ll_crypto_blkcipher_decrypt_iv( + &desc, &dst, &src, src.length); + } + + if (rc) { + CERROR("encrypt error %d\n", rc); + RETURN(rc); + } + + datalen += inobjs[i].len; + buf += inobjs[i].len; + } + + outobj->len = datalen; + RETURN(0); +} + +/* + * if adj_nob != 0, we adjust desc->bd_nob to the actual cipher text size. + */ +static +int krb5_encrypt_bulk(struct ll_crypto_cipher *tfm, + struct krb5_header *khdr, + char *confounder, + struct ptlrpc_bulk_desc *desc, + rawobj_t *cipher, + int adj_nob) +{ + struct blkcipher_desc ciph_desc; + __u8 local_iv[16] = {0}; + struct scatterlist src, dst; + int blocksize, i, rc, nob = 0; + + LASSERT(desc->bd_iov_count); + LASSERT(desc->bd_enc_iov); + + blocksize = ll_crypto_blkcipher_blocksize(tfm); + LASSERT(blocksize > 1); + LASSERT(cipher->len == blocksize + sizeof(*khdr)); + + ciph_desc.tfm = tfm; + ciph_desc.info = local_iv; + ciph_desc.flags = 0; + + /* encrypt confounder */ + buf_to_sg(&src, confounder, blocksize); + buf_to_sg(&dst, cipher->data, blocksize); + + rc = ll_crypto_blkcipher_encrypt_iv(&ciph_desc, &dst, &src, blocksize); + if (rc) { + CERROR("error to encrypt confounder: %d\n", rc); + return rc; + } + + /* encrypt clear pages */ + for (i = 0; i < desc->bd_iov_count; i++) { + sg_set_page(&src, desc->bd_iov[i].kiov_page, + (desc->bd_iov[i].kiov_len + blocksize - 1) & + (~(blocksize - 1)), + desc->bd_iov[i].kiov_offset); + if (adj_nob) + nob += src.length; + sg_set_page(&dst, desc->bd_enc_iov[i].kiov_page, src.length, + src.offset); + + desc->bd_enc_iov[i].kiov_offset = dst.offset; + desc->bd_enc_iov[i].kiov_len = dst.length; + + rc = ll_crypto_blkcipher_encrypt_iv(&ciph_desc, &dst, &src, + src.length); + if (rc) { + CERROR("error to encrypt page: %d\n", rc); + return rc; + } + } + + /* encrypt krb5 header */ + buf_to_sg(&src, khdr, sizeof(*khdr)); + buf_to_sg(&dst, cipher->data + blocksize, sizeof(*khdr)); + + rc = ll_crypto_blkcipher_encrypt_iv(&ciph_desc, + &dst, &src, sizeof(*khdr)); + if (rc) { + CERROR("error to encrypt krb5 header: %d\n", rc); + return rc; + } + + if (adj_nob) + desc->bd_nob = nob; + + return 0; +} + +/* + * desc->bd_nob_transferred is the size of cipher text received. + * desc->bd_nob is the target size of plain text supposed to be. + * + * if adj_nob != 0, we adjust each page's kiov_len to the actual + * plain text size. + * - for client read: we don't know data size for each page, so + * bd_iov[]->kiov_len is set to PAGE_SIZE, but actual data received might + * be smaller, so we need to adjust it according to bd_enc_iov[]->kiov_len. + * this means we DO NOT support the situation that server send an odd size + * data in a page which is not the last one. + * - for server write: we knows exactly data size for each page being expected, + * thus kiov_len is accurate already, so we should not adjust it at all. + * and bd_enc_iov[]->kiov_len should be round_up(bd_iov[]->kiov_len) which + * should have been done by prep_bulk(). + */ +static +int krb5_decrypt_bulk(struct ll_crypto_cipher *tfm, + struct krb5_header *khdr, + struct ptlrpc_bulk_desc *desc, + rawobj_t *cipher, + rawobj_t *plain, + int adj_nob) +{ + struct blkcipher_desc ciph_desc; + __u8 local_iv[16] = {0}; + struct scatterlist src, dst; + int ct_nob = 0, pt_nob = 0; + int blocksize, i, rc; + + LASSERT(desc->bd_iov_count); + LASSERT(desc->bd_enc_iov); + LASSERT(desc->bd_nob_transferred); + + blocksize = ll_crypto_blkcipher_blocksize(tfm); + LASSERT(blocksize > 1); + LASSERT(cipher->len == blocksize + sizeof(*khdr)); + + ciph_desc.tfm = tfm; + ciph_desc.info = local_iv; + ciph_desc.flags = 0; + + if (desc->bd_nob_transferred % blocksize) { + CERROR("odd transferred nob: %d\n", desc->bd_nob_transferred); + return -EPROTO; + } + + /* decrypt head (confounder) */ + buf_to_sg(&src, cipher->data, blocksize); + buf_to_sg(&dst, plain->data, blocksize); + + rc = ll_crypto_blkcipher_decrypt_iv(&ciph_desc, &dst, &src, blocksize); + if (rc) { + CERROR("error to decrypt confounder: %d\n", rc); + return rc; + } + + for (i = 0; i < desc->bd_iov_count && ct_nob < desc->bd_nob_transferred; + i++) { + if (desc->bd_enc_iov[i].kiov_offset % blocksize != 0 || + desc->bd_enc_iov[i].kiov_len % blocksize != 0) { + CERROR("page %d: odd offset %u len %u, blocksize %d\n", + i, desc->bd_enc_iov[i].kiov_offset, + desc->bd_enc_iov[i].kiov_len, blocksize); + return -EFAULT; + } + + if (adj_nob) { + if (ct_nob + desc->bd_enc_iov[i].kiov_len > + desc->bd_nob_transferred) + desc->bd_enc_iov[i].kiov_len = + desc->bd_nob_transferred - ct_nob; + + desc->bd_iov[i].kiov_len = desc->bd_enc_iov[i].kiov_len; + if (pt_nob + desc->bd_enc_iov[i].kiov_len >desc->bd_nob) + desc->bd_iov[i].kiov_len = desc->bd_nob -pt_nob; + } else { + /* this should be guaranteed by LNET */ + LASSERT(ct_nob + desc->bd_enc_iov[i].kiov_len <= + desc->bd_nob_transferred); + LASSERT(desc->bd_iov[i].kiov_len <= + desc->bd_enc_iov[i].kiov_len); + } + + if (desc->bd_enc_iov[i].kiov_len == 0) + continue; + + sg_set_page(&src, desc->bd_enc_iov[i].kiov_page, + desc->bd_enc_iov[i].kiov_len, + desc->bd_enc_iov[i].kiov_offset); + dst = src; + if (desc->bd_iov[i].kiov_len % blocksize == 0) + sg_assign_page(&dst, desc->bd_iov[i].kiov_page); + + rc = ll_crypto_blkcipher_decrypt_iv(&ciph_desc, &dst, &src, + src.length); + if (rc) { + CERROR("error to decrypt page: %d\n", rc); + return rc; + } + + if (desc->bd_iov[i].kiov_len % blocksize != 0) { + memcpy(page_address(desc->bd_iov[i].kiov_page) + + desc->bd_iov[i].kiov_offset, + page_address(desc->bd_enc_iov[i].kiov_page) + + desc->bd_iov[i].kiov_offset, + desc->bd_iov[i].kiov_len); + } + + ct_nob += desc->bd_enc_iov[i].kiov_len; + pt_nob += desc->bd_iov[i].kiov_len; + } + + if (unlikely(ct_nob != desc->bd_nob_transferred)) { + CERROR("%d cipher text transferred but only %d decrypted\n", + desc->bd_nob_transferred, ct_nob); + return -EFAULT; + } + + if (unlikely(!adj_nob && pt_nob != desc->bd_nob)) { + CERROR("%d plain text expected but only %d received\n", + desc->bd_nob, pt_nob); + return -EFAULT; + } + + /* if needed, clear up the rest unused iovs */ + if (adj_nob) + while (i < desc->bd_iov_count) + desc->bd_iov[i++].kiov_len = 0; + + /* decrypt tail (krb5 header) */ + buf_to_sg(&src, cipher->data + blocksize, sizeof(*khdr)); + buf_to_sg(&dst, cipher->data + blocksize, sizeof(*khdr)); + + rc = ll_crypto_blkcipher_decrypt_iv(&ciph_desc, + &dst, &src, sizeof(*khdr)); + if (rc) { + CERROR("error to decrypt tail: %d\n", rc); + return rc; + } + + if (memcmp(cipher->data + blocksize, khdr, sizeof(*khdr))) { + CERROR("krb5 header doesn't match\n"); + return -EACCES; + } + + return 0; +} + +static +__u32 gss_wrap_kerberos(struct gss_ctx *gctx, + rawobj_t *gsshdr, + rawobj_t *msg, + int msg_buflen, + rawobj_t *token) +{ + struct krb5_ctx *kctx = gctx->internal_ctx_id; + struct krb5_enctype *ke = &enctypes[kctx->kc_enctype]; + struct krb5_header *khdr; + int blocksize; + rawobj_t cksum = RAWOBJ_EMPTY; + rawobj_t data_desc[3], cipher; + __u8 conf[GSS_MAX_CIPHER_BLOCK]; + int rc = 0; + + LASSERT(ke); + LASSERT(ke->ke_conf_size <= GSS_MAX_CIPHER_BLOCK); + LASSERT(kctx->kc_keye.kb_tfm == NULL || + ke->ke_conf_size >= + ll_crypto_blkcipher_blocksize(kctx->kc_keye.kb_tfm)); + + /* + * final token format: + * --------------------------------------------------- + * | krb5 header | cipher text | checksum (16 bytes) | + * --------------------------------------------------- + */ + + /* fill krb5 header */ + LASSERT(token->len >= sizeof(*khdr)); + khdr = (struct krb5_header *) token->data; + fill_krb5_header(kctx, khdr, 1); + + /* generate confounder */ + cfs_get_random_bytes(conf, ke->ke_conf_size); + + /* get encryption blocksize. note kc_keye might not associated with + * a tfm, currently only for arcfour-hmac */ + if (kctx->kc_enctype == ENCTYPE_ARCFOUR_HMAC) { + LASSERT(kctx->kc_keye.kb_tfm == NULL); + blocksize = 1; + } else { + LASSERT(kctx->kc_keye.kb_tfm); + blocksize = ll_crypto_blkcipher_blocksize(kctx->kc_keye.kb_tfm); + } + LASSERT(blocksize <= ke->ke_conf_size); + + /* padding the message */ + if (add_padding(msg, msg_buflen, blocksize)) + return GSS_S_FAILURE; + + /* + * clear text layout for checksum: + * ------------------------------------------------------ + * | confounder | gss header | clear msgs | krb5 header | + * ------------------------------------------------------ + */ + data_desc[0].data = conf; + data_desc[0].len = ke->ke_conf_size; + data_desc[1].data = gsshdr->data; + data_desc[1].len = gsshdr->len; + data_desc[2].data = msg->data; + data_desc[2].len = msg->len; + + /* compute checksum */ + if (krb5_make_checksum(kctx->kc_enctype, &kctx->kc_keyi, + khdr, 3, data_desc, 0, NULL, &cksum)) + return GSS_S_FAILURE; + LASSERT(cksum.len >= ke->ke_hash_size); + + /* + * clear text layout for encryption: + * ----------------------------------------- + * | confounder | clear msgs | krb5 header | + * ----------------------------------------- + */ + data_desc[0].data = conf; + data_desc[0].len = ke->ke_conf_size; + data_desc[1].data = msg->data; + data_desc[1].len = msg->len; + data_desc[2].data = (__u8 *) khdr; + data_desc[2].len = sizeof(*khdr); + + /* cipher text will be directly inplace */ + cipher.data = (__u8 *) (khdr + 1); + cipher.len = token->len - sizeof(*khdr); + LASSERT(cipher.len >= ke->ke_conf_size + msg->len + sizeof(*khdr)); + + if (kctx->kc_enctype == ENCTYPE_ARCFOUR_HMAC) { + rawobj_t arc4_keye; + struct ll_crypto_cipher *arc4_tfm; + + if (krb5_make_checksum(ENCTYPE_ARCFOUR_HMAC, &kctx->kc_keyi, + NULL, 1, &cksum, 0, NULL, &arc4_keye)) { + CERROR("failed to obtain arc4 enc key\n"); + GOTO(arc4_out, rc = -EACCES); + } + + arc4_tfm = ll_crypto_alloc_blkcipher("ecb(arc4)", 0, 0); + if (IS_ERR(arc4_tfm)) { + CERROR("failed to alloc tfm arc4 in ECB mode\n"); + GOTO(arc4_out_key, rc = -EACCES); + } + + if (ll_crypto_blkcipher_setkey(arc4_tfm, arc4_keye.data, + arc4_keye.len)) { + CERROR("failed to set arc4 key, len %d\n", + arc4_keye.len); + GOTO(arc4_out_tfm, rc = -EACCES); + } + + rc = krb5_encrypt_rawobjs(arc4_tfm, 1, + 3, data_desc, &cipher, 1); +arc4_out_tfm: + ll_crypto_free_blkcipher(arc4_tfm); +arc4_out_key: + rawobj_free(&arc4_keye); +arc4_out: + do {} while(0); /* just to avoid compile warning */ + } else { + rc = krb5_encrypt_rawobjs(kctx->kc_keye.kb_tfm, 0, + 3, data_desc, &cipher, 1); + } + + if (rc != 0) { + rawobj_free(&cksum); + return GSS_S_FAILURE; + } + + /* fill in checksum */ + LASSERT(token->len >= sizeof(*khdr) + cipher.len + ke->ke_hash_size); + memcpy((char *)(khdr + 1) + cipher.len, + cksum.data + cksum.len - ke->ke_hash_size, + ke->ke_hash_size); + rawobj_free(&cksum); + + /* final token length */ + token->len = sizeof(*khdr) + cipher.len + ke->ke_hash_size; + return GSS_S_COMPLETE; +} + +static +__u32 gss_prep_bulk_kerberos(struct gss_ctx *gctx, + struct ptlrpc_bulk_desc *desc) +{ + struct krb5_ctx *kctx = gctx->internal_ctx_id; + int blocksize, i; + + LASSERT(desc->bd_iov_count); + LASSERT(desc->bd_enc_iov); + LASSERT(kctx->kc_keye.kb_tfm); + + blocksize = ll_crypto_blkcipher_blocksize(kctx->kc_keye.kb_tfm); + + for (i = 0; i < desc->bd_iov_count; i++) { + LASSERT(desc->bd_enc_iov[i].kiov_page); + /* + * offset should always start at page boundary of either + * client or server side. + */ + if (desc->bd_iov[i].kiov_offset & blocksize) { + CERROR("odd offset %d in page %d\n", + desc->bd_iov[i].kiov_offset, i); + return GSS_S_FAILURE; + } + + desc->bd_enc_iov[i].kiov_offset = desc->bd_iov[i].kiov_offset; + desc->bd_enc_iov[i].kiov_len = (desc->bd_iov[i].kiov_len + + blocksize - 1) & (~(blocksize - 1)); + } + + return GSS_S_COMPLETE; +} + +static +__u32 gss_wrap_bulk_kerberos(struct gss_ctx *gctx, + struct ptlrpc_bulk_desc *desc, + rawobj_t *token, int adj_nob) +{ + struct krb5_ctx *kctx = gctx->internal_ctx_id; + struct krb5_enctype *ke = &enctypes[kctx->kc_enctype]; + struct krb5_header *khdr; + int blocksize; + rawobj_t cksum = RAWOBJ_EMPTY; + rawobj_t data_desc[1], cipher; + __u8 conf[GSS_MAX_CIPHER_BLOCK]; + int rc = 0; + + LASSERT(ke); + LASSERT(ke->ke_conf_size <= GSS_MAX_CIPHER_BLOCK); + + /* + * final token format: + * -------------------------------------------------- + * | krb5 header | head/tail cipher text | checksum | + * -------------------------------------------------- + */ + + /* fill krb5 header */ + LASSERT(token->len >= sizeof(*khdr)); + khdr = (struct krb5_header *) token->data; + fill_krb5_header(kctx, khdr, 1); + + /* generate confounder */ + cfs_get_random_bytes(conf, ke->ke_conf_size); + + /* get encryption blocksize. note kc_keye might not associated with + * a tfm, currently only for arcfour-hmac */ + if (kctx->kc_enctype == ENCTYPE_ARCFOUR_HMAC) { + LASSERT(kctx->kc_keye.kb_tfm == NULL); + blocksize = 1; + } else { + LASSERT(kctx->kc_keye.kb_tfm); + blocksize = ll_crypto_blkcipher_blocksize(kctx->kc_keye.kb_tfm); + } + + /* + * we assume the size of krb5_header (16 bytes) must be n * blocksize. + * the bulk token size would be exactly (sizeof(krb5_header) + + * blocksize + sizeof(krb5_header) + hashsize) + */ + LASSERT(blocksize <= ke->ke_conf_size); + LASSERT(sizeof(*khdr) >= blocksize && sizeof(*khdr) % blocksize == 0); + LASSERT(token->len >= sizeof(*khdr) + blocksize + sizeof(*khdr) + 16); + + /* + * clear text layout for checksum: + * ------------------------------------------ + * | confounder | clear pages | krb5 header | + * ------------------------------------------ + */ + data_desc[0].data = conf; + data_desc[0].len = ke->ke_conf_size; + + /* compute checksum */ + if (krb5_make_checksum(kctx->kc_enctype, &kctx->kc_keyi, + khdr, 1, data_desc, + desc->bd_iov_count, desc->bd_iov, + &cksum)) + return GSS_S_FAILURE; + LASSERT(cksum.len >= ke->ke_hash_size); + + /* + * clear text layout for encryption: + * ------------------------------------------ + * | confounder | clear pages | krb5 header | + * ------------------------------------------ + * | | | + * ---------- (cipher pages) | + * result token: | | + * ------------------------------------------- + * | krb5 header | cipher text | cipher text | + * ------------------------------------------- + */ + data_desc[0].data = conf; + data_desc[0].len = ke->ke_conf_size; + + cipher.data = (__u8 *) (khdr + 1); + cipher.len = blocksize + sizeof(*khdr); + + if (kctx->kc_enctype == ENCTYPE_ARCFOUR_HMAC) { + LBUG(); + rc = 0; + } else { + rc = krb5_encrypt_bulk(kctx->kc_keye.kb_tfm, khdr, + conf, desc, &cipher, adj_nob); + } + + if (rc != 0) { + rawobj_free(&cksum); + return GSS_S_FAILURE; + } + + /* fill in checksum */ + LASSERT(token->len >= sizeof(*khdr) + cipher.len + ke->ke_hash_size); + memcpy((char *)(khdr + 1) + cipher.len, + cksum.data + cksum.len - ke->ke_hash_size, + ke->ke_hash_size); + rawobj_free(&cksum); + + /* final token length */ + token->len = sizeof(*khdr) + cipher.len + ke->ke_hash_size; + return GSS_S_COMPLETE; +} + +static +__u32 gss_unwrap_kerberos(struct gss_ctx *gctx, + rawobj_t *gsshdr, + rawobj_t *token, + rawobj_t *msg) +{ + struct krb5_ctx *kctx = gctx->internal_ctx_id; + struct krb5_enctype *ke = &enctypes[kctx->kc_enctype]; + struct krb5_header *khdr; + unsigned char *tmpbuf; + int blocksize, bodysize; + rawobj_t cksum = RAWOBJ_EMPTY; + rawobj_t cipher_in, plain_out; + rawobj_t hash_objs[3]; + int rc = 0; + __u32 major; + + LASSERT(ke); + + if (token->len < sizeof(*khdr)) { + CERROR("short signature: %u\n", token->len); + return GSS_S_DEFECTIVE_TOKEN; + } + + khdr = (struct krb5_header *) token->data; + + major = verify_krb5_header(kctx, khdr, 1); + if (major != GSS_S_COMPLETE) { + CERROR("bad krb5 header\n"); + return major; + } + + /* block size */ + if (kctx->kc_enctype == ENCTYPE_ARCFOUR_HMAC) { + LASSERT(kctx->kc_keye.kb_tfm == NULL); + blocksize = 1; + } else { + LASSERT(kctx->kc_keye.kb_tfm); + blocksize = ll_crypto_blkcipher_blocksize(kctx->kc_keye.kb_tfm); + } + + /* expected token layout: + * ---------------------------------------- + * | krb5 header | cipher text | checksum | + * ---------------------------------------- + */ + bodysize = token->len - sizeof(*khdr) - ke->ke_hash_size; + + if (bodysize % blocksize) { + CERROR("odd bodysize %d\n", bodysize); + return GSS_S_DEFECTIVE_TOKEN; + } + + if (bodysize <= ke->ke_conf_size + sizeof(*khdr)) { + CERROR("incomplete token: bodysize %d\n", bodysize); + return GSS_S_DEFECTIVE_TOKEN; + } + + if (msg->len < bodysize - ke->ke_conf_size - sizeof(*khdr)) { + CERROR("buffer too small: %u, require %d\n", + msg->len, bodysize - ke->ke_conf_size); + return GSS_S_FAILURE; + } + + /* decrypting */ + OBD_ALLOC_LARGE(tmpbuf, bodysize); + if (!tmpbuf) + return GSS_S_FAILURE; + + major = GSS_S_FAILURE; + + cipher_in.data = (__u8 *) (khdr + 1); + cipher_in.len = bodysize; + plain_out.data = tmpbuf; + plain_out.len = bodysize; + + if (kctx->kc_enctype == ENCTYPE_ARCFOUR_HMAC) { + rawobj_t arc4_keye; + struct ll_crypto_cipher *arc4_tfm; + + cksum.data = token->data + token->len - ke->ke_hash_size; + cksum.len = ke->ke_hash_size; + + if (krb5_make_checksum(ENCTYPE_ARCFOUR_HMAC, &kctx->kc_keyi, + NULL, 1, &cksum, 0, NULL, &arc4_keye)) { + CERROR("failed to obtain arc4 enc key\n"); + GOTO(arc4_out, rc = -EACCES); + } + + arc4_tfm = ll_crypto_alloc_blkcipher("ecb(arc4)", 0, 0); + if (IS_ERR(arc4_tfm)) { + CERROR("failed to alloc tfm arc4 in ECB mode\n"); + GOTO(arc4_out_key, rc = -EACCES); + } + + if (ll_crypto_blkcipher_setkey(arc4_tfm, + arc4_keye.data, arc4_keye.len)) { + CERROR("failed to set arc4 key, len %d\n", + arc4_keye.len); + GOTO(arc4_out_tfm, rc = -EACCES); + } + + rc = krb5_encrypt_rawobjs(arc4_tfm, 1, + 1, &cipher_in, &plain_out, 0); +arc4_out_tfm: + ll_crypto_free_blkcipher(arc4_tfm); +arc4_out_key: + rawobj_free(&arc4_keye); +arc4_out: + cksum = RAWOBJ_EMPTY; + } else { + rc = krb5_encrypt_rawobjs(kctx->kc_keye.kb_tfm, 0, + 1, &cipher_in, &plain_out, 0); + } + + if (rc != 0) { + CERROR("error decrypt\n"); + goto out_free; + } + LASSERT(plain_out.len == bodysize); + + /* expected clear text layout: + * ----------------------------------------- + * | confounder | clear msgs | krb5 header | + * ----------------------------------------- + */ + + /* verify krb5 header in token is not modified */ + if (memcmp(khdr, plain_out.data + plain_out.len - sizeof(*khdr), + sizeof(*khdr))) { + CERROR("decrypted krb5 header mismatch\n"); + goto out_free; + } + + /* verify checksum, compose clear text as layout: + * ------------------------------------------------------ + * | confounder | gss header | clear msgs | krb5 header | + * ------------------------------------------------------ + */ + hash_objs[0].len = ke->ke_conf_size; + hash_objs[0].data = plain_out.data; + hash_objs[1].len = gsshdr->len; + hash_objs[1].data = gsshdr->data; + hash_objs[2].len = plain_out.len - ke->ke_conf_size - sizeof(*khdr); + hash_objs[2].data = plain_out.data + ke->ke_conf_size; + if (krb5_make_checksum(kctx->kc_enctype, &kctx->kc_keyi, + khdr, 3, hash_objs, 0, NULL, &cksum)) + goto out_free; + + LASSERT(cksum.len >= ke->ke_hash_size); + if (memcmp((char *)(khdr + 1) + bodysize, + cksum.data + cksum.len - ke->ke_hash_size, + ke->ke_hash_size)) { + CERROR("checksum mismatch\n"); + goto out_free; + } + + msg->len = bodysize - ke->ke_conf_size - sizeof(*khdr); + memcpy(msg->data, tmpbuf + ke->ke_conf_size, msg->len); + + major = GSS_S_COMPLETE; +out_free: + OBD_FREE_LARGE(tmpbuf, bodysize); + rawobj_free(&cksum); + return major; +} + +static +__u32 gss_unwrap_bulk_kerberos(struct gss_ctx *gctx, + struct ptlrpc_bulk_desc *desc, + rawobj_t *token, int adj_nob) +{ + struct krb5_ctx *kctx = gctx->internal_ctx_id; + struct krb5_enctype *ke = &enctypes[kctx->kc_enctype]; + struct krb5_header *khdr; + int blocksize; + rawobj_t cksum = RAWOBJ_EMPTY; + rawobj_t cipher, plain; + rawobj_t data_desc[1]; + int rc; + __u32 major; + + LASSERT(ke); + + if (token->len < sizeof(*khdr)) { + CERROR("short signature: %u\n", token->len); + return GSS_S_DEFECTIVE_TOKEN; + } + + khdr = (struct krb5_header *) token->data; + + major = verify_krb5_header(kctx, khdr, 1); + if (major != GSS_S_COMPLETE) { + CERROR("bad krb5 header\n"); + return major; + } + + /* block size */ + if (kctx->kc_enctype == ENCTYPE_ARCFOUR_HMAC) { + LASSERT(kctx->kc_keye.kb_tfm == NULL); + blocksize = 1; + LBUG(); + } else { + LASSERT(kctx->kc_keye.kb_tfm); + blocksize = ll_crypto_blkcipher_blocksize(kctx->kc_keye.kb_tfm); + } + LASSERT(sizeof(*khdr) >= blocksize && sizeof(*khdr) % blocksize == 0); + + /* + * token format is expected as: + * ----------------------------------------------- + * | krb5 header | head/tail cipher text | cksum | + * ----------------------------------------------- + */ + if (token->len < sizeof(*khdr) + blocksize + sizeof(*khdr) + + ke->ke_hash_size) { + CERROR("short token size: %u\n", token->len); + return GSS_S_DEFECTIVE_TOKEN; + } + + cipher.data = (__u8 *) (khdr + 1); + cipher.len = blocksize + sizeof(*khdr); + plain.data = cipher.data; + plain.len = cipher.len; + + rc = krb5_decrypt_bulk(kctx->kc_keye.kb_tfm, khdr, + desc, &cipher, &plain, adj_nob); + if (rc) + return GSS_S_DEFECTIVE_TOKEN; + + /* + * verify checksum, compose clear text as layout: + * ------------------------------------------ + * | confounder | clear pages | krb5 header | + * ------------------------------------------ + */ + data_desc[0].data = plain.data; + data_desc[0].len = blocksize; + + if (krb5_make_checksum(kctx->kc_enctype, &kctx->kc_keyi, + khdr, 1, data_desc, + desc->bd_iov_count, desc->bd_iov, + &cksum)) + return GSS_S_FAILURE; + LASSERT(cksum.len >= ke->ke_hash_size); + + if (memcmp(plain.data + blocksize + sizeof(*khdr), + cksum.data + cksum.len - ke->ke_hash_size, + ke->ke_hash_size)) { + CERROR("checksum mismatch\n"); + rawobj_free(&cksum); + return GSS_S_BAD_SIG; + } + + rawobj_free(&cksum); + return GSS_S_COMPLETE; +} + +int gss_display_kerberos(struct gss_ctx *ctx, + char *buf, + int bufsize) +{ + struct krb5_ctx *kctx = ctx->internal_ctx_id; + int written; + + written = snprintf(buf, bufsize, "krb5 (%s)", + enctype2str(kctx->kc_enctype)); + return written; +} + +static struct gss_api_ops gss_kerberos_ops = { + .gss_import_sec_context = gss_import_sec_context_kerberos, + .gss_copy_reverse_context = gss_copy_reverse_context_kerberos, + .gss_inquire_context = gss_inquire_context_kerberos, + .gss_get_mic = gss_get_mic_kerberos, + .gss_verify_mic = gss_verify_mic_kerberos, + .gss_wrap = gss_wrap_kerberos, + .gss_unwrap = gss_unwrap_kerberos, + .gss_prep_bulk = gss_prep_bulk_kerberos, + .gss_wrap_bulk = gss_wrap_bulk_kerberos, + .gss_unwrap_bulk = gss_unwrap_bulk_kerberos, + .gss_delete_sec_context = gss_delete_sec_context_kerberos, + .gss_display = gss_display_kerberos, +}; + +static struct subflavor_desc gss_kerberos_sfs[] = { + { + .sf_subflavor = SPTLRPC_SUBFLVR_KRB5N, + .sf_qop = 0, + .sf_service = SPTLRPC_SVC_NULL, + .sf_name = "krb5n" + }, + { + .sf_subflavor = SPTLRPC_SUBFLVR_KRB5A, + .sf_qop = 0, + .sf_service = SPTLRPC_SVC_AUTH, + .sf_name = "krb5a" + }, + { + .sf_subflavor = SPTLRPC_SUBFLVR_KRB5I, + .sf_qop = 0, + .sf_service = SPTLRPC_SVC_INTG, + .sf_name = "krb5i" + }, + { + .sf_subflavor = SPTLRPC_SUBFLVR_KRB5P, + .sf_qop = 0, + .sf_service = SPTLRPC_SVC_PRIV, + .sf_name = "krb5p" + }, +}; + +/* + * currently we leave module owner NULL + */ +static struct gss_api_mech gss_kerberos_mech = { + .gm_owner = NULL, /*THIS_MODULE, */ + .gm_name = "krb5", + .gm_oid = (rawobj_t) + {9, "\052\206\110\206\367\022\001\002\002"}, + .gm_ops = &gss_kerberos_ops, + .gm_sf_num = 4, + .gm_sfs = gss_kerberos_sfs, +}; + +int __init init_kerberos_module(void) +{ + int status; + + spin_lock_init(&krb5_seq_lock); + + status = lgss_mech_register(&gss_kerberos_mech); + if (status) + CERROR("Failed to register kerberos gss mechanism!\n"); + return status; +} + +void __exit cleanup_kerberos_module(void) +{ + lgss_mech_unregister(&gss_kerberos_mech); +} |