[funini.com] -> [kei@sodan] -> Kernel Reading

root/net/sunrpc/auth_gss/gss_krb5_mech.c

/* [<][>][^][v][top][bottom][index][help] */

DEFINITIONS

This source file includes following definitions.
  1. simple_get_bytes
  2. simple_get_netobj
  3. get_key
  4. gss_import_sec_context_kerberos
  5. gss_delete_sec_context_kerberos
  6. init_kerberos_module
  7. cleanup_kerberos_module

/*
 *  linux/net/sunrpc/gss_krb5_mech.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.
 *
 */

#include <linux/err.h>
#include <linux/module.h>
#include <linux/init.h>
#include <linux/types.h>
#include <linux/slab.h>
#include <linux/sunrpc/auth.h>
#include <linux/sunrpc/gss_krb5.h>
#include <linux/sunrpc/xdr.h>
#include <linux/crypto.h>

#ifdef RPC_DEBUG
# define RPCDBG_FACILITY        RPCDBG_AUTH
#endif

static const void *
simple_get_bytes(const void *p, const void *end, void *res, int len)
{
        const void *q = (const void *)((const char *)p + len);
        if (unlikely(q > end || q < p))
                return ERR_PTR(-EFAULT);
        memcpy(res, p, len);
        return q;
}

static const void *
simple_get_netobj(const void *p, const void *end, struct xdr_netobj *res)
{
        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 = kmemdup(p, len, GFP_NOFS);
        if (unlikely(res->data == NULL))
                return ERR_PTR(-ENOMEM);
        res->len = len;
        return q;
}

static inline const void *
get_key(const void *p, const void *end, struct crypto_blkcipher **res)
{
        struct xdr_netobj       key;
        int                     alg;
        char                    *alg_name;

        p = simple_get_bytes(p, end, &alg, sizeof(alg));
        if (IS_ERR(p))
                goto out_err;
        p = simple_get_netobj(p, end, &key);
        if (IS_ERR(p))
                goto out_err;

        switch (alg) {
                case ENCTYPE_DES_CBC_RAW:
                        alg_name = "cbc(des)";
                        break;
                default:
                        printk("gss_kerberos_mech: unsupported algorithm %d\n", alg);
                        goto out_err_free_key;
        }
        *res = crypto_alloc_blkcipher(alg_name, 0, CRYPTO_ALG_ASYNC);
        if (IS_ERR(*res)) {
                printk("gss_kerberos_mech: unable to initialize crypto algorithm %s\n", alg_name);
                *res = NULL;
                goto out_err_free_key;
        }
        if (crypto_blkcipher_setkey(*res, key.data, key.len)) {
                printk("gss_kerberos_mech: error setting key for crypto algorithm %s\n", alg_name);
                goto out_err_free_tfm;
        }

        kfree(key.data);
        return p;

out_err_free_tfm:
        crypto_free_blkcipher(*res);
out_err_free_key:
        kfree(key.data);
        p = ERR_PTR(-EINVAL);
out_err:
        return p;
}

static int
gss_import_sec_context_kerberos(const void *p,
                                size_t len,
                                struct gss_ctx *ctx_id)
{
        const void *end = (const void *)((const char *)p + len);
        struct  krb5_ctx *ctx;
        int tmp;

        if (!(ctx = kzalloc(sizeof(*ctx), GFP_NOFS)))
                goto out_err;

        p = simple_get_bytes(p, end, &ctx->initiate, sizeof(ctx->initiate));
        if (IS_ERR(p))
                goto out_err_free_ctx;
        /* The downcall format was designed before we completely understood
         * the uses of the context fields; so it includes some stuff we
         * just give some minimal sanity-checking, and some we ignore
         * completely (like the next twenty bytes): */
        if (unlikely(p + 20 > end || p + 20 < p))
                goto out_err_free_ctx;
        p += 20;
        p = simple_get_bytes(p, end, &tmp, sizeof(tmp));
        if (IS_ERR(p))
                goto out_err_free_ctx;
        if (tmp != SGN_ALG_DES_MAC_MD5) {
                p = ERR_PTR(-ENOSYS);
                goto out_err_free_ctx;
        }
        p = simple_get_bytes(p, end, &tmp, sizeof(tmp));
        if (IS_ERR(p))
                goto out_err_free_ctx;
        if (tmp != SEAL_ALG_DES) {
                p = ERR_PTR(-ENOSYS);
                goto out_err_free_ctx;
        }
        p = simple_get_bytes(p, end, &ctx->endtime, sizeof(ctx->endtime));
        if (IS_ERR(p))
                goto out_err_free_ctx;
        p = simple_get_bytes(p, end, &ctx->seq_send, sizeof(ctx->seq_send));
        if (IS_ERR(p))
                goto out_err_free_ctx;
        p = simple_get_netobj(p, end, &ctx->mech_used);
        if (IS_ERR(p))
                goto out_err_free_ctx;
        p = get_key(p, end, &ctx->enc);
        if (IS_ERR(p))
                goto out_err_free_mech;
        p = get_key(p, end, &ctx->seq);
        if (IS_ERR(p))
                goto out_err_free_key1;
        if (p != end) {
                p = ERR_PTR(-EFAULT);
                goto out_err_free_key2;
        }

        ctx_id->internal_ctx_id = ctx;

        dprintk("RPC:       Successfully imported new context.\n");
        return 0;

out_err_free_key2:
        crypto_free_blkcipher(ctx->seq);
out_err_free_key1:
        crypto_free_blkcipher(ctx->enc);
out_err_free_mech:
        kfree(ctx->mech_used.data);
out_err_free_ctx:
        kfree(ctx);
out_err:
        return PTR_ERR(p);
}

static void
gss_delete_sec_context_kerberos(void *internal_ctx) {
        struct krb5_ctx *kctx = internal_ctx;

        crypto_free_blkcipher(kctx->seq);
        crypto_free_blkcipher(kctx->enc);
        kfree(kctx->mech_used.data);
        kfree(kctx);
}

static const struct gss_api_ops gss_kerberos_ops = {
        .gss_import_sec_context = gss_import_sec_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_delete_sec_context = gss_delete_sec_context_kerberos,
};

static struct pf_desc gss_kerberos_pfs[] = {
        [0] = {
                .pseudoflavor = RPC_AUTH_GSS_KRB5,
                .service = RPC_GSS_SVC_NONE,
                .name = "krb5",
        },
        [1] = {
                .pseudoflavor = RPC_AUTH_GSS_KRB5I,
                .service = RPC_GSS_SVC_INTEGRITY,
                .name = "krb5i",
        },
        [2] = {
                .pseudoflavor = RPC_AUTH_GSS_KRB5P,
                .service = RPC_GSS_SVC_PRIVACY,
                .name = "krb5p",
        },
};

static struct gss_api_mech gss_kerberos_mech = {
        .gm_name        = "krb5",
        .gm_owner       = THIS_MODULE,
        .gm_oid         = {9, (void *)"\x2a\x86\x48\x86\xf7\x12\x01\x02\x02"},
        .gm_ops         = &gss_kerberos_ops,
        .gm_pf_num      = ARRAY_SIZE(gss_kerberos_pfs),
        .gm_pfs         = gss_kerberos_pfs,
};

static int __init init_kerberos_module(void)
{
        int status;

        status = gss_mech_register(&gss_kerberos_mech);
        if (status)
                printk("Failed to register kerberos gss mechanism!\n");
        return status;
}

static void __exit cleanup_kerberos_module(void)
{
        gss_mech_unregister(&gss_kerberos_mech);
}

MODULE_LICENSE("GPL");
module_init(init_kerberos_module);
module_exit(cleanup_kerberos_module);

/* [<][>][^][v][top][bottom][index][help] */

[funini.com] -> [kei@sodan] -> Kernel Reading