794 строки
15 KiB
C
794 строки
15 KiB
C
/*
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* xfrm algorithm interface
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*
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* Copyright (c) 2002 James Morris <jmorris@intercode.com.au>
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*
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* This program is free software; you can redistribute it and/or modify it
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* under the terms of the GNU General Public License as published by the Free
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* Software Foundation; either version 2 of the License, or (at your option)
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* any later version.
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*/
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#include <linux/module.h>
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#include <linux/kernel.h>
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#include <linux/pfkeyv2.h>
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#include <linux/crypto.h>
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#include <net/xfrm.h>
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#if defined(CONFIG_INET_AH) || defined(CONFIG_INET_AH_MODULE) || defined(CONFIG_INET6_AH) || defined(CONFIG_INET6_AH_MODULE)
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#include <net/ah.h>
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#endif
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#if defined(CONFIG_INET_ESP) || defined(CONFIG_INET_ESP_MODULE) || defined(CONFIG_INET6_ESP) || defined(CONFIG_INET6_ESP_MODULE)
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#include <net/esp.h>
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#endif
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#include <asm/scatterlist.h>
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/*
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* Algorithms supported by IPsec. These entries contain properties which
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* are used in key negotiation and xfrm processing, and are used to verify
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* that instantiated crypto transforms have correct parameters for IPsec
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* purposes.
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*/
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static struct xfrm_algo_desc aalg_list[] = {
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{
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.name = "hmac(digest_null)",
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.compat = "digest_null",
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.uinfo = {
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.auth = {
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.icv_truncbits = 0,
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.icv_fullbits = 0,
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}
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},
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.desc = {
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.sadb_alg_id = SADB_X_AALG_NULL,
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.sadb_alg_ivlen = 0,
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.sadb_alg_minbits = 0,
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.sadb_alg_maxbits = 0
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}
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},
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{
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.name = "hmac(md5)",
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.compat = "md5",
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.uinfo = {
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.auth = {
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.icv_truncbits = 96,
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.icv_fullbits = 128,
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}
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},
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.desc = {
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.sadb_alg_id = SADB_AALG_MD5HMAC,
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.sadb_alg_ivlen = 0,
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.sadb_alg_minbits = 128,
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.sadb_alg_maxbits = 128
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}
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},
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{
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.name = "hmac(sha1)",
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.compat = "sha1",
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.uinfo = {
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.auth = {
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.icv_truncbits = 96,
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.icv_fullbits = 160,
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}
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},
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.desc = {
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.sadb_alg_id = SADB_AALG_SHA1HMAC,
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.sadb_alg_ivlen = 0,
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.sadb_alg_minbits = 160,
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.sadb_alg_maxbits = 160
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}
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},
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{
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.name = "hmac(sha256)",
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.compat = "sha256",
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.uinfo = {
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.auth = {
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.icv_truncbits = 96,
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.icv_fullbits = 256,
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}
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},
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.desc = {
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.sadb_alg_id = SADB_X_AALG_SHA2_256HMAC,
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.sadb_alg_ivlen = 0,
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.sadb_alg_minbits = 256,
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.sadb_alg_maxbits = 256
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}
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},
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{
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.name = "hmac(ripemd160)",
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.compat = "ripemd160",
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.uinfo = {
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.auth = {
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.icv_truncbits = 96,
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.icv_fullbits = 160,
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}
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},
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.desc = {
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.sadb_alg_id = SADB_X_AALG_RIPEMD160HMAC,
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.sadb_alg_ivlen = 0,
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.sadb_alg_minbits = 160,
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.sadb_alg_maxbits = 160
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}
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},
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{
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.name = "xcbc(aes)",
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.uinfo = {
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.auth = {
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.icv_truncbits = 96,
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.icv_fullbits = 128,
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}
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},
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.desc = {
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.sadb_alg_id = SADB_X_AALG_AES_XCBC_MAC,
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.sadb_alg_ivlen = 0,
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.sadb_alg_minbits = 128,
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.sadb_alg_maxbits = 128
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}
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},
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};
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static struct xfrm_algo_desc ealg_list[] = {
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{
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.name = "ecb(cipher_null)",
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.compat = "cipher_null",
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.uinfo = {
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.encr = {
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.blockbits = 8,
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.defkeybits = 0,
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}
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},
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.desc = {
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.sadb_alg_id = SADB_EALG_NULL,
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.sadb_alg_ivlen = 0,
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.sadb_alg_minbits = 0,
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.sadb_alg_maxbits = 0
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}
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},
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{
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.name = "cbc(des)",
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.compat = "des",
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.uinfo = {
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.encr = {
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.blockbits = 64,
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.defkeybits = 64,
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}
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},
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.desc = {
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.sadb_alg_id = SADB_EALG_DESCBC,
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.sadb_alg_ivlen = 8,
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.sadb_alg_minbits = 64,
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.sadb_alg_maxbits = 64
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}
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},
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{
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.name = "cbc(des3_ede)",
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.compat = "des3_ede",
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.uinfo = {
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.encr = {
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.blockbits = 64,
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.defkeybits = 192,
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}
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},
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.desc = {
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.sadb_alg_id = SADB_EALG_3DESCBC,
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.sadb_alg_ivlen = 8,
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.sadb_alg_minbits = 192,
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.sadb_alg_maxbits = 192
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}
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},
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{
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.name = "cbc(cast128)",
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.compat = "cast128",
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.uinfo = {
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.encr = {
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.blockbits = 64,
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.defkeybits = 128,
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}
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},
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.desc = {
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.sadb_alg_id = SADB_X_EALG_CASTCBC,
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.sadb_alg_ivlen = 8,
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.sadb_alg_minbits = 40,
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.sadb_alg_maxbits = 128
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}
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},
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{
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.name = "cbc(blowfish)",
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.compat = "blowfish",
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.uinfo = {
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.encr = {
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.blockbits = 64,
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.defkeybits = 128,
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}
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},
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.desc = {
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.sadb_alg_id = SADB_X_EALG_BLOWFISHCBC,
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.sadb_alg_ivlen = 8,
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.sadb_alg_minbits = 40,
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.sadb_alg_maxbits = 448
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}
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},
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{
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.name = "cbc(aes)",
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.compat = "aes",
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.uinfo = {
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.encr = {
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.blockbits = 128,
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.defkeybits = 128,
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}
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},
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.desc = {
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.sadb_alg_id = SADB_X_EALG_AESCBC,
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.sadb_alg_ivlen = 8,
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.sadb_alg_minbits = 128,
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.sadb_alg_maxbits = 256
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}
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},
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{
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.name = "cbc(serpent)",
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.compat = "serpent",
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.uinfo = {
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.encr = {
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.blockbits = 128,
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.defkeybits = 128,
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}
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},
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.desc = {
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.sadb_alg_id = SADB_X_EALG_SERPENTCBC,
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.sadb_alg_ivlen = 8,
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.sadb_alg_minbits = 128,
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.sadb_alg_maxbits = 256,
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}
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},
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{
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.name = "cbc(camellia)",
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.uinfo = {
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.encr = {
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.blockbits = 128,
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.defkeybits = 128,
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}
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},
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.desc = {
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.sadb_alg_id = SADB_X_EALG_CAMELLIACBC,
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.sadb_alg_ivlen = 8,
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.sadb_alg_minbits = 128,
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.sadb_alg_maxbits = 256
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}
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},
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{
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.name = "cbc(twofish)",
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.compat = "twofish",
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.uinfo = {
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.encr = {
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.blockbits = 128,
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.defkeybits = 128,
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}
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},
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.desc = {
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.sadb_alg_id = SADB_X_EALG_TWOFISHCBC,
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.sadb_alg_ivlen = 8,
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.sadb_alg_minbits = 128,
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.sadb_alg_maxbits = 256
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}
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},
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};
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static struct xfrm_algo_desc calg_list[] = {
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{
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.name = "deflate",
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.uinfo = {
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.comp = {
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.threshold = 90,
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}
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},
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.desc = { .sadb_alg_id = SADB_X_CALG_DEFLATE }
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},
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{
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.name = "lzs",
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.uinfo = {
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.comp = {
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.threshold = 90,
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}
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},
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.desc = { .sadb_alg_id = SADB_X_CALG_LZS }
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},
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{
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.name = "lzjh",
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.uinfo = {
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.comp = {
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.threshold = 50,
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}
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},
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.desc = { .sadb_alg_id = SADB_X_CALG_LZJH }
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},
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};
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static inline int aalg_entries(void)
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{
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return ARRAY_SIZE(aalg_list);
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}
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static inline int ealg_entries(void)
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{
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return ARRAY_SIZE(ealg_list);
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}
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static inline int calg_entries(void)
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{
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return ARRAY_SIZE(calg_list);
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}
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/* Todo: generic iterators */
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struct xfrm_algo_desc *xfrm_aalg_get_byid(int alg_id)
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{
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int i;
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for (i = 0; i < aalg_entries(); i++) {
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if (aalg_list[i].desc.sadb_alg_id == alg_id) {
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if (aalg_list[i].available)
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return &aalg_list[i];
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else
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break;
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}
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}
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return NULL;
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}
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EXPORT_SYMBOL_GPL(xfrm_aalg_get_byid);
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struct xfrm_algo_desc *xfrm_ealg_get_byid(int alg_id)
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{
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int i;
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for (i = 0; i < ealg_entries(); i++) {
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if (ealg_list[i].desc.sadb_alg_id == alg_id) {
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if (ealg_list[i].available)
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return &ealg_list[i];
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else
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break;
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}
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}
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return NULL;
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}
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EXPORT_SYMBOL_GPL(xfrm_ealg_get_byid);
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struct xfrm_algo_desc *xfrm_calg_get_byid(int alg_id)
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{
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int i;
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for (i = 0; i < calg_entries(); i++) {
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if (calg_list[i].desc.sadb_alg_id == alg_id) {
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if (calg_list[i].available)
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return &calg_list[i];
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else
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break;
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}
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}
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return NULL;
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}
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EXPORT_SYMBOL_GPL(xfrm_calg_get_byid);
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static struct xfrm_algo_desc *xfrm_get_byname(struct xfrm_algo_desc *list,
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int entries, u32 type, u32 mask,
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char *name, int probe)
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{
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int i, status;
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if (!name)
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return NULL;
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for (i = 0; i < entries; i++) {
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if (strcmp(name, list[i].name) &&
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(!list[i].compat || strcmp(name, list[i].compat)))
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continue;
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if (list[i].available)
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return &list[i];
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if (!probe)
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break;
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status = crypto_has_alg(list[i].name, type,
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mask | CRYPTO_ALG_ASYNC);
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if (!status)
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break;
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list[i].available = status;
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return &list[i];
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}
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return NULL;
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}
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struct xfrm_algo_desc *xfrm_aalg_get_byname(char *name, int probe)
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{
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return xfrm_get_byname(aalg_list, aalg_entries(),
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CRYPTO_ALG_TYPE_HASH, CRYPTO_ALG_TYPE_HASH_MASK,
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name, probe);
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}
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EXPORT_SYMBOL_GPL(xfrm_aalg_get_byname);
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struct xfrm_algo_desc *xfrm_ealg_get_byname(char *name, int probe)
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{
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return xfrm_get_byname(ealg_list, ealg_entries(),
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CRYPTO_ALG_TYPE_BLKCIPHER, CRYPTO_ALG_TYPE_MASK,
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name, probe);
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}
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EXPORT_SYMBOL_GPL(xfrm_ealg_get_byname);
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struct xfrm_algo_desc *xfrm_calg_get_byname(char *name, int probe)
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{
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return xfrm_get_byname(calg_list, calg_entries(),
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CRYPTO_ALG_TYPE_COMPRESS, CRYPTO_ALG_TYPE_MASK,
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name, probe);
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}
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EXPORT_SYMBOL_GPL(xfrm_calg_get_byname);
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struct xfrm_algo_desc *xfrm_aalg_get_byidx(unsigned int idx)
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{
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if (idx >= aalg_entries())
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return NULL;
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return &aalg_list[idx];
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}
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EXPORT_SYMBOL_GPL(xfrm_aalg_get_byidx);
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struct xfrm_algo_desc *xfrm_ealg_get_byidx(unsigned int idx)
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{
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if (idx >= ealg_entries())
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return NULL;
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return &ealg_list[idx];
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}
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EXPORT_SYMBOL_GPL(xfrm_ealg_get_byidx);
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/*
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* Probe for the availability of crypto algorithms, and set the available
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* flag for any algorithms found on the system. This is typically called by
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* pfkey during userspace SA add, update or register.
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*/
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void xfrm_probe_algs(void)
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{
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#ifdef CONFIG_CRYPTO
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int i, status;
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BUG_ON(in_softirq());
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for (i = 0; i < aalg_entries(); i++) {
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status = crypto_has_hash(aalg_list[i].name, 0,
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CRYPTO_ALG_ASYNC);
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if (aalg_list[i].available != status)
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aalg_list[i].available = status;
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}
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for (i = 0; i < ealg_entries(); i++) {
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status = crypto_has_blkcipher(ealg_list[i].name, 0,
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CRYPTO_ALG_ASYNC);
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if (ealg_list[i].available != status)
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ealg_list[i].available = status;
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}
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for (i = 0; i < calg_entries(); i++) {
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status = crypto_has_comp(calg_list[i].name, 0,
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CRYPTO_ALG_ASYNC);
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if (calg_list[i].available != status)
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calg_list[i].available = status;
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}
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#endif
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}
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EXPORT_SYMBOL_GPL(xfrm_probe_algs);
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int xfrm_count_auth_supported(void)
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{
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int i, n;
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for (i = 0, n = 0; i < aalg_entries(); i++)
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if (aalg_list[i].available)
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n++;
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return n;
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}
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EXPORT_SYMBOL_GPL(xfrm_count_auth_supported);
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int xfrm_count_enc_supported(void)
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{
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int i, n;
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for (i = 0, n = 0; i < ealg_entries(); i++)
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if (ealg_list[i].available)
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n++;
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return n;
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}
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EXPORT_SYMBOL_GPL(xfrm_count_enc_supported);
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/* Move to common area: it is shared with AH. */
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int skb_icv_walk(const struct sk_buff *skb, struct hash_desc *desc,
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int offset, int len, icv_update_fn_t icv_update)
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{
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int start = skb_headlen(skb);
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int i, copy = start - offset;
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int err;
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struct scatterlist sg;
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/* Checksum header. */
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if (copy > 0) {
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if (copy > len)
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copy = len;
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sg.page = virt_to_page(skb->data + offset);
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sg.offset = (unsigned long)(skb->data + offset) % PAGE_SIZE;
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sg.length = copy;
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err = icv_update(desc, &sg, copy);
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if (unlikely(err))
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return err;
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if ((len -= copy) == 0)
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return 0;
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offset += copy;
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}
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|
|
for (i = 0; i < skb_shinfo(skb)->nr_frags; i++) {
|
|
int end;
|
|
|
|
BUG_TRAP(start <= offset + len);
|
|
|
|
end = start + skb_shinfo(skb)->frags[i].size;
|
|
if ((copy = end - offset) > 0) {
|
|
skb_frag_t *frag = &skb_shinfo(skb)->frags[i];
|
|
|
|
if (copy > len)
|
|
copy = len;
|
|
|
|
sg.page = frag->page;
|
|
sg.offset = frag->page_offset + offset-start;
|
|
sg.length = copy;
|
|
|
|
err = icv_update(desc, &sg, copy);
|
|
if (unlikely(err))
|
|
return err;
|
|
|
|
if (!(len -= copy))
|
|
return 0;
|
|
offset += copy;
|
|
}
|
|
start = end;
|
|
}
|
|
|
|
if (skb_shinfo(skb)->frag_list) {
|
|
struct sk_buff *list = skb_shinfo(skb)->frag_list;
|
|
|
|
for (; list; list = list->next) {
|
|
int end;
|
|
|
|
BUG_TRAP(start <= offset + len);
|
|
|
|
end = start + list->len;
|
|
if ((copy = end - offset) > 0) {
|
|
if (copy > len)
|
|
copy = len;
|
|
err = skb_icv_walk(list, desc, offset-start,
|
|
copy, icv_update);
|
|
if (unlikely(err))
|
|
return err;
|
|
if ((len -= copy) == 0)
|
|
return 0;
|
|
offset += copy;
|
|
}
|
|
start = end;
|
|
}
|
|
}
|
|
BUG_ON(len);
|
|
return 0;
|
|
}
|
|
EXPORT_SYMBOL_GPL(skb_icv_walk);
|
|
|
|
#if defined(CONFIG_INET_ESP) || defined(CONFIG_INET_ESP_MODULE) || defined(CONFIG_INET6_ESP) || defined(CONFIG_INET6_ESP_MODULE)
|
|
|
|
/* Looking generic it is not used in another places. */
|
|
|
|
int
|
|
skb_to_sgvec(struct sk_buff *skb, struct scatterlist *sg, int offset, int len)
|
|
{
|
|
int start = skb_headlen(skb);
|
|
int i, copy = start - offset;
|
|
int elt = 0;
|
|
|
|
if (copy > 0) {
|
|
if (copy > len)
|
|
copy = len;
|
|
sg[elt].page = virt_to_page(skb->data + offset);
|
|
sg[elt].offset = (unsigned long)(skb->data + offset) % PAGE_SIZE;
|
|
sg[elt].length = copy;
|
|
elt++;
|
|
if ((len -= copy) == 0)
|
|
return elt;
|
|
offset += copy;
|
|
}
|
|
|
|
for (i = 0; i < skb_shinfo(skb)->nr_frags; i++) {
|
|
int end;
|
|
|
|
BUG_TRAP(start <= offset + len);
|
|
|
|
end = start + skb_shinfo(skb)->frags[i].size;
|
|
if ((copy = end - offset) > 0) {
|
|
skb_frag_t *frag = &skb_shinfo(skb)->frags[i];
|
|
|
|
if (copy > len)
|
|
copy = len;
|
|
sg[elt].page = frag->page;
|
|
sg[elt].offset = frag->page_offset+offset-start;
|
|
sg[elt].length = copy;
|
|
elt++;
|
|
if (!(len -= copy))
|
|
return elt;
|
|
offset += copy;
|
|
}
|
|
start = end;
|
|
}
|
|
|
|
if (skb_shinfo(skb)->frag_list) {
|
|
struct sk_buff *list = skb_shinfo(skb)->frag_list;
|
|
|
|
for (; list; list = list->next) {
|
|
int end;
|
|
|
|
BUG_TRAP(start <= offset + len);
|
|
|
|
end = start + list->len;
|
|
if ((copy = end - offset) > 0) {
|
|
if (copy > len)
|
|
copy = len;
|
|
elt += skb_to_sgvec(list, sg+elt, offset - start, copy);
|
|
if ((len -= copy) == 0)
|
|
return elt;
|
|
offset += copy;
|
|
}
|
|
start = end;
|
|
}
|
|
}
|
|
BUG_ON(len);
|
|
return elt;
|
|
}
|
|
EXPORT_SYMBOL_GPL(skb_to_sgvec);
|
|
|
|
/* Check that skb data bits are writable. If they are not, copy data
|
|
* to newly created private area. If "tailbits" is given, make sure that
|
|
* tailbits bytes beyond current end of skb are writable.
|
|
*
|
|
* Returns amount of elements of scatterlist to load for subsequent
|
|
* transformations and pointer to writable trailer skb.
|
|
*/
|
|
|
|
int skb_cow_data(struct sk_buff *skb, int tailbits, struct sk_buff **trailer)
|
|
{
|
|
int copyflag;
|
|
int elt;
|
|
struct sk_buff *skb1, **skb_p;
|
|
|
|
/* If skb is cloned or its head is paged, reallocate
|
|
* head pulling out all the pages (pages are considered not writable
|
|
* at the moment even if they are anonymous).
|
|
*/
|
|
if ((skb_cloned(skb) || skb_shinfo(skb)->nr_frags) &&
|
|
__pskb_pull_tail(skb, skb_pagelen(skb)-skb_headlen(skb)) == NULL)
|
|
return -ENOMEM;
|
|
|
|
/* Easy case. Most of packets will go this way. */
|
|
if (!skb_shinfo(skb)->frag_list) {
|
|
/* A little of trouble, not enough of space for trailer.
|
|
* This should not happen, when stack is tuned to generate
|
|
* good frames. OK, on miss we reallocate and reserve even more
|
|
* space, 128 bytes is fair. */
|
|
|
|
if (skb_tailroom(skb) < tailbits &&
|
|
pskb_expand_head(skb, 0, tailbits-skb_tailroom(skb)+128, GFP_ATOMIC))
|
|
return -ENOMEM;
|
|
|
|
/* Voila! */
|
|
*trailer = skb;
|
|
return 1;
|
|
}
|
|
|
|
/* Misery. We are in troubles, going to mincer fragments... */
|
|
|
|
elt = 1;
|
|
skb_p = &skb_shinfo(skb)->frag_list;
|
|
copyflag = 0;
|
|
|
|
while ((skb1 = *skb_p) != NULL) {
|
|
int ntail = 0;
|
|
|
|
/* The fragment is partially pulled by someone,
|
|
* this can happen on input. Copy it and everything
|
|
* after it. */
|
|
|
|
if (skb_shared(skb1))
|
|
copyflag = 1;
|
|
|
|
/* If the skb is the last, worry about trailer. */
|
|
|
|
if (skb1->next == NULL && tailbits) {
|
|
if (skb_shinfo(skb1)->nr_frags ||
|
|
skb_shinfo(skb1)->frag_list ||
|
|
skb_tailroom(skb1) < tailbits)
|
|
ntail = tailbits + 128;
|
|
}
|
|
|
|
if (copyflag ||
|
|
skb_cloned(skb1) ||
|
|
ntail ||
|
|
skb_shinfo(skb1)->nr_frags ||
|
|
skb_shinfo(skb1)->frag_list) {
|
|
struct sk_buff *skb2;
|
|
|
|
/* Fuck, we are miserable poor guys... */
|
|
if (ntail == 0)
|
|
skb2 = skb_copy(skb1, GFP_ATOMIC);
|
|
else
|
|
skb2 = skb_copy_expand(skb1,
|
|
skb_headroom(skb1),
|
|
ntail,
|
|
GFP_ATOMIC);
|
|
if (unlikely(skb2 == NULL))
|
|
return -ENOMEM;
|
|
|
|
if (skb1->sk)
|
|
skb_set_owner_w(skb2, skb1->sk);
|
|
|
|
/* Looking around. Are we still alive?
|
|
* OK, link new skb, drop old one */
|
|
|
|
skb2->next = skb1->next;
|
|
*skb_p = skb2;
|
|
kfree_skb(skb1);
|
|
skb1 = skb2;
|
|
}
|
|
elt++;
|
|
*trailer = skb1;
|
|
skb_p = &skb1->next;
|
|
}
|
|
|
|
return elt;
|
|
}
|
|
EXPORT_SYMBOL_GPL(skb_cow_data);
|
|
|
|
void *pskb_put(struct sk_buff *skb, struct sk_buff *tail, int len)
|
|
{
|
|
if (tail != skb) {
|
|
skb->data_len += len;
|
|
skb->len += len;
|
|
}
|
|
return skb_put(tail, len);
|
|
}
|
|
EXPORT_SYMBOL_GPL(pskb_put);
|
|
#endif
|