diff options
Diffstat (limited to 'crypto/ccm.c')
| -rw-r--r-- | crypto/ccm.c | 1045 |
1 files changed, 1045 insertions, 0 deletions
diff --git a/crypto/ccm.c b/crypto/ccm.c new file mode 100644 index 000000000..8104c564d --- /dev/null +++ b/crypto/ccm.c @@ -0,0 +1,1045 @@ +/* + * CCM: Counter with CBC-MAC + * + * (C) Copyright IBM Corp. 2007 - Joy Latten <latten@us.ibm.com> + * + * This program is free software; you can redistribute it and/or modify it + * under the terms of the GNU General Public License as published by the Free + * Software Foundation; either version 2 of the License, or (at your option) + * any later version. + * + */ + +#include <crypto/internal/aead.h> +#include <crypto/internal/hash.h> +#include <crypto/internal/skcipher.h> +#include <crypto/scatterwalk.h> +#include <linux/err.h> +#include <linux/init.h> +#include <linux/kernel.h> +#include <linux/module.h> +#include <linux/slab.h> + +#include "internal.h" + +struct ccm_instance_ctx { + struct crypto_skcipher_spawn ctr; + struct crypto_ahash_spawn mac; +}; + +struct crypto_ccm_ctx { + struct crypto_ahash *mac; + struct crypto_skcipher *ctr; +}; + +struct crypto_rfc4309_ctx { + struct crypto_aead *child; + u8 nonce[3]; +}; + +struct crypto_rfc4309_req_ctx { + struct scatterlist src[3]; + struct scatterlist dst[3]; + struct aead_request subreq; +}; + +struct crypto_ccm_req_priv_ctx { + u8 odata[16]; + u8 idata[16]; + u8 auth_tag[16]; + u32 flags; + struct scatterlist src[3]; + struct scatterlist dst[3]; + struct skcipher_request skreq; +}; + +struct cbcmac_tfm_ctx { + struct crypto_cipher *child; +}; + +struct cbcmac_desc_ctx { + unsigned int len; +}; + +static inline struct crypto_ccm_req_priv_ctx *crypto_ccm_reqctx( + struct aead_request *req) +{ + unsigned long align = crypto_aead_alignmask(crypto_aead_reqtfm(req)); + + return (void *)PTR_ALIGN((u8 *)aead_request_ctx(req), align + 1); +} + +static int set_msg_len(u8 *block, unsigned int msglen, int csize) +{ + __be32 data; + + memset(block, 0, csize); + block += csize; + + if (csize >= 4) + csize = 4; + else if (msglen > (1 << (8 * csize))) + return -EOVERFLOW; + + data = cpu_to_be32(msglen); + memcpy(block - csize, (u8 *)&data + 4 - csize, csize); + + return 0; +} + +static int crypto_ccm_setkey(struct crypto_aead *aead, const u8 *key, + unsigned int keylen) +{ + struct crypto_ccm_ctx *ctx = crypto_aead_ctx(aead); + struct crypto_skcipher *ctr = ctx->ctr; + struct crypto_ahash *mac = ctx->mac; + int err = 0; + + crypto_skcipher_clear_flags(ctr, CRYPTO_TFM_REQ_MASK); + crypto_skcipher_set_flags(ctr, crypto_aead_get_flags(aead) & + CRYPTO_TFM_REQ_MASK); + err = crypto_skcipher_setkey(ctr, key, keylen); + crypto_aead_set_flags(aead, crypto_skcipher_get_flags(ctr) & + CRYPTO_TFM_RES_MASK); + if (err) + goto out; + + crypto_ahash_clear_flags(mac, CRYPTO_TFM_REQ_MASK); + crypto_ahash_set_flags(mac, crypto_aead_get_flags(aead) & + CRYPTO_TFM_REQ_MASK); + err = crypto_ahash_setkey(mac, key, keylen); + crypto_aead_set_flags(aead, crypto_ahash_get_flags(mac) & + CRYPTO_TFM_RES_MASK); + +out: + return err; +} + +static int crypto_ccm_setauthsize(struct crypto_aead *tfm, + unsigned int authsize) +{ + switch (authsize) { + case 4: + case 6: + case 8: + case 10: + case 12: + case 14: + case 16: + break; + default: + return -EINVAL; + } + + return 0; +} + +static int format_input(u8 *info, struct aead_request *req, + unsigned int cryptlen) +{ + struct crypto_aead *aead = crypto_aead_reqtfm(req); + unsigned int lp = req->iv[0]; + unsigned int l = lp + 1; + unsigned int m; + + m = crypto_aead_authsize(aead); + + memcpy(info, req->iv, 16); + + /* format control info per RFC 3610 and + * NIST Special Publication 800-38C + */ + *info |= (8 * ((m - 2) / 2)); + if (req->assoclen) + *info |= 64; + + return set_msg_len(info + 16 - l, cryptlen, l); +} + +static int format_adata(u8 *adata, unsigned int a) +{ + int len = 0; + + /* add control info for associated data + * RFC 3610 and NIST Special Publication 800-38C + */ + if (a < 65280) { + *(__be16 *)adata = cpu_to_be16(a); + len = 2; + } else { + *(__be16 *)adata = cpu_to_be16(0xfffe); + *(__be32 *)&adata[2] = cpu_to_be32(a); + len = 6; + } + + return len; +} + +static int crypto_ccm_auth(struct aead_request *req, struct scatterlist *plain, + unsigned int cryptlen) +{ + struct crypto_ccm_req_priv_ctx *pctx = crypto_ccm_reqctx(req); + struct crypto_aead *aead = crypto_aead_reqtfm(req); + struct crypto_ccm_ctx *ctx = crypto_aead_ctx(aead); + AHASH_REQUEST_ON_STACK(ahreq, ctx->mac); + unsigned int assoclen = req->assoclen; + struct scatterlist sg[3]; + u8 *odata = pctx->odata; + u8 *idata = pctx->idata; + int ilen, err; + + /* format control data for input */ + err = format_input(odata, req, cryptlen); + if (err) + goto out; + + sg_init_table(sg, 3); + sg_set_buf(&sg[0], odata, 16); + + /* format associated data and compute into mac */ + if (assoclen) { + ilen = format_adata(idata, assoclen); + sg_set_buf(&sg[1], idata, ilen); + sg_chain(sg, 3, req->src); + } else { + ilen = 0; + sg_chain(sg, 2, req->src); + } + + ahash_request_set_tfm(ahreq, ctx->mac); + ahash_request_set_callback(ahreq, pctx->flags, NULL, NULL); + ahash_request_set_crypt(ahreq, sg, NULL, assoclen + ilen + 16); + err = crypto_ahash_init(ahreq); + if (err) + goto out; + err = crypto_ahash_update(ahreq); + if (err) + goto out; + + /* we need to pad the MAC input to a round multiple of the block size */ + ilen = 16 - (assoclen + ilen) % 16; + if (ilen < 16) { + memset(idata, 0, ilen); + sg_init_table(sg, 2); + sg_set_buf(&sg[0], idata, ilen); + if (plain) + sg_chain(sg, 2, plain); + plain = sg; + cryptlen += ilen; + } + + ahash_request_set_crypt(ahreq, plain, pctx->odata, cryptlen); + err = crypto_ahash_finup(ahreq); +out: + return err; +} + +static void crypto_ccm_encrypt_done(struct crypto_async_request *areq, int err) +{ + struct aead_request *req = areq->data; + struct crypto_aead *aead = crypto_aead_reqtfm(req); + struct crypto_ccm_req_priv_ctx *pctx = crypto_ccm_reqctx(req); + u8 *odata = pctx->odata; + + if (!err) + scatterwalk_map_and_copy(odata, req->dst, + req->assoclen + req->cryptlen, + crypto_aead_authsize(aead), 1); + aead_request_complete(req, err); +} + +static inline int crypto_ccm_check_iv(const u8 *iv) +{ + /* 2 <= L <= 8, so 1 <= L' <= 7. */ + if (1 > iv[0] || iv[0] > 7) + return -EINVAL; + + return 0; +} + +static int crypto_ccm_init_crypt(struct aead_request *req, u8 *tag) +{ + struct crypto_ccm_req_priv_ctx *pctx = crypto_ccm_reqctx(req); + struct scatterlist *sg; + u8 *iv = req->iv; + int err; + + err = crypto_ccm_check_iv(iv); + if (err) + return err; + + pctx->flags = aead_request_flags(req); + + /* Note: rfc 3610 and NIST 800-38C require counter of + * zero to encrypt auth tag. + */ + memset(iv + 15 - iv[0], 0, iv[0] + 1); + + sg_init_table(pctx->src, 3); + sg_set_buf(pctx->src, tag, 16); + sg = scatterwalk_ffwd(pctx->src + 1, req->src, req->assoclen); + if (sg != pctx->src + 1) + sg_chain(pctx->src, 2, sg); + + if (req->src != req->dst) { + sg_init_table(pctx->dst, 3); + sg_set_buf(pctx->dst, tag, 16); + sg = scatterwalk_ffwd(pctx->dst + 1, req->dst, req->assoclen); + if (sg != pctx->dst + 1) + sg_chain(pctx->dst, 2, sg); + } + + return 0; +} + +static int crypto_ccm_encrypt(struct aead_request *req) +{ + struct crypto_aead *aead = crypto_aead_reqtfm(req); + struct crypto_ccm_ctx *ctx = crypto_aead_ctx(aead); + struct crypto_ccm_req_priv_ctx *pctx = crypto_ccm_reqctx(req); + struct skcipher_request *skreq = &pctx->skreq; + struct scatterlist *dst; + unsigned int cryptlen = req->cryptlen; + u8 *odata = pctx->odata; + u8 *iv = req->iv; + int err; + + err = crypto_ccm_init_crypt(req, odata); + if (err) + return err; + + err = crypto_ccm_auth(req, sg_next(pctx->src), cryptlen); + if (err) + return err; + + dst = pctx->src; + if (req->src != req->dst) + dst = pctx->dst; + + skcipher_request_set_tfm(skreq, ctx->ctr); + skcipher_request_set_callback(skreq, pctx->flags, + crypto_ccm_encrypt_done, req); + skcipher_request_set_crypt(skreq, pctx->src, dst, cryptlen + 16, iv); + err = crypto_skcipher_encrypt(skreq); + if (err) + return err; + + /* copy authtag to end of dst */ + scatterwalk_map_and_copy(odata, sg_next(dst), cryptlen, + crypto_aead_authsize(aead), 1); + return err; +} + +static void crypto_ccm_decrypt_done(struct crypto_async_request *areq, + int err) +{ + struct aead_request *req = areq->data; + struct crypto_ccm_req_priv_ctx *pctx = crypto_ccm_reqctx(req); + struct crypto_aead *aead = crypto_aead_reqtfm(req); + unsigned int authsize = crypto_aead_authsize(aead); + unsigned int cryptlen = req->cryptlen - authsize; + struct scatterlist *dst; + + pctx->flags = 0; + + dst = sg_next(req->src == req->dst ? pctx->src : pctx->dst); + + if (!err) { + err = crypto_ccm_auth(req, dst, cryptlen); + if (!err && crypto_memneq(pctx->auth_tag, pctx->odata, authsize)) + err = -EBADMSG; + } + aead_request_complete(req, err); +} + +static int crypto_ccm_decrypt(struct aead_request *req) +{ + struct crypto_aead *aead = crypto_aead_reqtfm(req); + struct crypto_ccm_ctx *ctx = crypto_aead_ctx(aead); + struct crypto_ccm_req_priv_ctx *pctx = crypto_ccm_reqctx(req); + struct skcipher_request *skreq = &pctx->skreq; + struct scatterlist *dst; + unsigned int authsize = crypto_aead_authsize(aead); + unsigned int cryptlen = req->cryptlen; + u8 *authtag = pctx->auth_tag; + u8 *odata = pctx->odata; + u8 *iv = pctx->idata; + int err; + + cryptlen -= authsize; + + err = crypto_ccm_init_crypt(req, authtag); + if (err) + return err; + + scatterwalk_map_and_copy(authtag, sg_next(pctx->src), cryptlen, + authsize, 0); + + dst = pctx->src; + if (req->src != req->dst) + dst = pctx->dst; + + memcpy(iv, req->iv, 16); + + skcipher_request_set_tfm(skreq, ctx->ctr); + skcipher_request_set_callback(skreq, pctx->flags, + crypto_ccm_decrypt_done, req); + skcipher_request_set_crypt(skreq, pctx->src, dst, cryptlen + 16, iv); + err = crypto_skcipher_decrypt(skreq); + if (err) + return err; + + err = crypto_ccm_auth(req, sg_next(dst), cryptlen); + if (err) + return err; + + /* verify */ + if (crypto_memneq(authtag, odata, authsize)) + return -EBADMSG; + + return err; +} + +static int crypto_ccm_init_tfm(struct crypto_aead *tfm) +{ + struct aead_instance *inst = aead_alg_instance(tfm); + struct ccm_instance_ctx *ictx = aead_instance_ctx(inst); + struct crypto_ccm_ctx *ctx = crypto_aead_ctx(tfm); + struct crypto_ahash *mac; + struct crypto_skcipher *ctr; + unsigned long align; + int err; + + mac = crypto_spawn_ahash(&ictx->mac); + if (IS_ERR(mac)) + return PTR_ERR(mac); + + ctr = crypto_spawn_skcipher(&ictx->ctr); + err = PTR_ERR(ctr); + if (IS_ERR(ctr)) + goto err_free_mac; + + ctx->mac = mac; + ctx->ctr = ctr; + + align = crypto_aead_alignmask(tfm); + align &= ~(crypto_tfm_ctx_alignment() - 1); + crypto_aead_set_reqsize( + tfm, + align + sizeof(struct crypto_ccm_req_priv_ctx) + + crypto_skcipher_reqsize(ctr)); + + return 0; + +err_free_mac: + crypto_free_ahash(mac); + return err; +} + +static void crypto_ccm_exit_tfm(struct crypto_aead *tfm) +{ + struct crypto_ccm_ctx *ctx = crypto_aead_ctx(tfm); + + crypto_free_ahash(ctx->mac); + crypto_free_skcipher(ctx->ctr); +} + +static void crypto_ccm_free(struct aead_instance *inst) +{ + struct ccm_instance_ctx *ctx = aead_instance_ctx(inst); + + crypto_drop_ahash(&ctx->mac); + crypto_drop_skcipher(&ctx->ctr); + kfree(inst); +} + +static int crypto_ccm_create_common(struct crypto_template *tmpl, + struct rtattr **tb, + const char *ctr_name, + const char *mac_name) +{ + struct crypto_attr_type *algt; + struct aead_instance *inst; + struct skcipher_alg *ctr; + struct crypto_alg *mac_alg; + struct hash_alg_common *mac; + struct ccm_instance_ctx *ictx; + int err; + + algt = crypto_get_attr_type(tb); + if (IS_ERR(algt)) + return PTR_ERR(algt); + + if ((algt->type ^ CRYPTO_ALG_TYPE_AEAD) & algt->mask) + return -EINVAL; + + mac_alg = crypto_find_alg(mac_name, &crypto_ahash_type, + CRYPTO_ALG_TYPE_HASH, + CRYPTO_ALG_TYPE_AHASH_MASK | + CRYPTO_ALG_ASYNC); + if (IS_ERR(mac_alg)) + return PTR_ERR(mac_alg); + + mac = __crypto_hash_alg_common(mac_alg); + err = -EINVAL; + if (strncmp(mac->base.cra_name, "cbcmac(", 7) != 0 || + mac->digestsize != 16) + goto out_put_mac; + + inst = kzalloc(sizeof(*inst) + sizeof(*ictx), GFP_KERNEL); + err = -ENOMEM; + if (!inst) + goto out_put_mac; + + ictx = aead_instance_ctx(inst); + err = crypto_init_ahash_spawn(&ictx->mac, mac, + aead_crypto_instance(inst)); + if (err) + goto err_free_inst; + + crypto_set_skcipher_spawn(&ictx->ctr, aead_crypto_instance(inst)); + err = crypto_grab_skcipher(&ictx->ctr, ctr_name, 0, + crypto_requires_sync(algt->type, + algt->mask)); + if (err) + goto err_drop_mac; + + ctr = crypto_spawn_skcipher_alg(&ictx->ctr); + + /* The skcipher algorithm must be CTR mode, using 16-byte blocks. */ + err = -EINVAL; + if (strncmp(ctr->base.cra_name, "ctr(", 4) != 0 || + crypto_skcipher_alg_ivsize(ctr) != 16 || + ctr->base.cra_blocksize != 1) + goto err_drop_ctr; + + /* ctr and cbcmac must use the same underlying block cipher. */ + if (strcmp(ctr->base.cra_name + 4, mac->base.cra_name + 7) != 0) + goto err_drop_ctr; + + err = -ENAMETOOLONG; + if (snprintf(inst->alg.base.cra_name, CRYPTO_MAX_ALG_NAME, + "ccm(%s", ctr->base.cra_name + 4) >= CRYPTO_MAX_ALG_NAME) + goto err_drop_ctr; + + if (snprintf(inst->alg.base.cra_driver_name, CRYPTO_MAX_ALG_NAME, + "ccm_base(%s,%s)", ctr->base.cra_driver_name, + mac->base.cra_driver_name) >= CRYPTO_MAX_ALG_NAME) + goto err_drop_ctr; + + inst->alg.base.cra_flags = ctr->base.cra_flags & CRYPTO_ALG_ASYNC; + inst->alg.base.cra_priority = (mac->base.cra_priority + + ctr->base.cra_priority) / 2; + inst->alg.base.cra_blocksize = 1; + inst->alg.base.cra_alignmask = mac->base.cra_alignmask | + ctr->base.cra_alignmask; + inst->alg.ivsize = 16; + inst->alg.chunksize = crypto_skcipher_alg_chunksize(ctr); + inst->alg.maxauthsize = 16; + inst->alg.base.cra_ctxsize = sizeof(struct crypto_ccm_ctx); + inst->alg.init = crypto_ccm_init_tfm; + inst->alg.exit = crypto_ccm_exit_tfm; + inst->alg.setkey = crypto_ccm_setkey; + inst->alg.setauthsize = crypto_ccm_setauthsize; + inst->alg.encrypt = crypto_ccm_encrypt; + inst->alg.decrypt = crypto_ccm_decrypt; + + inst->free = crypto_ccm_free; + + err = aead_register_instance(tmpl, inst); + if (err) + goto err_drop_ctr; + +out_put_mac: + crypto_mod_put(mac_alg); + return err; + +err_drop_ctr: + crypto_drop_skcipher(&ictx->ctr); +err_drop_mac: + crypto_drop_ahash(&ictx->mac); +err_free_inst: + kfree(inst); + goto out_put_mac; +} + +static int crypto_ccm_create(struct crypto_template *tmpl, struct rtattr **tb) +{ + const char *cipher_name; + char ctr_name[CRYPTO_MAX_ALG_NAME]; + char mac_name[CRYPTO_MAX_ALG_NAME]; + + cipher_name = crypto_attr_alg_name(tb[1]); + if (IS_ERR(cipher_name)) + return PTR_ERR(cipher_name); + + if (snprintf(ctr_name, CRYPTO_MAX_ALG_NAME, "ctr(%s)", + cipher_name) >= CRYPTO_MAX_ALG_NAME) + return -ENAMETOOLONG; + + if (snprintf(mac_name, CRYPTO_MAX_ALG_NAME, "cbcmac(%s)", + cipher_name) >= CRYPTO_MAX_ALG_NAME) + return -ENAMETOOLONG; + + return crypto_ccm_create_common(tmpl, tb, ctr_name, mac_name); +} + +static struct crypto_template crypto_ccm_tmpl = { + .name = "ccm", + .create = crypto_ccm_create, + .module = THIS_MODULE, +}; + +static int crypto_ccm_base_create(struct crypto_template *tmpl, + struct rtattr **tb) +{ + const char *ctr_name; + const char *mac_name; + + ctr_name = crypto_attr_alg_name(tb[1]); + if (IS_ERR(ctr_name)) + return PTR_ERR(ctr_name); + + mac_name = crypto_attr_alg_name(tb[2]); + if (IS_ERR(mac_name)) + return PTR_ERR(mac_name); + + return crypto_ccm_create_common(tmpl, tb, ctr_name, mac_name); +} + +static struct crypto_template crypto_ccm_base_tmpl = { + .name = "ccm_base", + .create = crypto_ccm_base_create, + .module = THIS_MODULE, +}; + +static int crypto_rfc4309_setkey(struct crypto_aead *parent, const u8 *key, + unsigned int keylen) +{ + struct crypto_rfc4309_ctx *ctx = crypto_aead_ctx(parent); + struct crypto_aead *child = ctx->child; + int err; + + if (keylen < 3) + return -EINVAL; + + keylen -= 3; + memcpy(ctx->nonce, key + keylen, 3); + + crypto_aead_clear_flags(child, CRYPTO_TFM_REQ_MASK); + crypto_aead_set_flags(child, crypto_aead_get_flags(parent) & + CRYPTO_TFM_REQ_MASK); + err = crypto_aead_setkey(child, key, keylen); + crypto_aead_set_flags(parent, crypto_aead_get_flags(child) & + CRYPTO_TFM_RES_MASK); + + return err; +} + +static int crypto_rfc4309_setauthsize(struct crypto_aead *parent, + unsigned int authsize) +{ + struct crypto_rfc4309_ctx *ctx = crypto_aead_ctx(parent); + + switch (authsize) { + case 8: + case 12: + case 16: + break; + default: + return -EINVAL; + } + + return crypto_aead_setauthsize(ctx->child, authsize); +} + +static struct aead_request *crypto_rfc4309_crypt(struct aead_request *req) +{ + struct crypto_rfc4309_req_ctx *rctx = aead_request_ctx(req); + struct aead_request *subreq = &rctx->subreq; + struct crypto_aead *aead = crypto_aead_reqtfm(req); + struct crypto_rfc4309_ctx *ctx = crypto_aead_ctx(aead); + struct crypto_aead *child = ctx->child; + struct scatterlist *sg; + u8 *iv = PTR_ALIGN((u8 *)(subreq + 1) + crypto_aead_reqsize(child), + crypto_aead_alignmask(child) + 1); + + /* L' */ + iv[0] = 3; + + memcpy(iv + 1, ctx->nonce, 3); + memcpy(iv + 4, req->iv, 8); + + scatterwalk_map_and_copy(iv + 16, req->src, 0, req->assoclen - 8, 0); + + sg_init_table(rctx->src, 3); + sg_set_buf(rctx->src, iv + 16, req->assoclen - 8); + sg = scatterwalk_ffwd(rctx->src + 1, req->src, req->assoclen); + if (sg != rctx->src + 1) + sg_chain(rctx->src, 2, sg); + + if (req->src != req->dst) { + sg_init_table(rctx->dst, 3); + sg_set_buf(rctx->dst, iv + 16, req->assoclen - 8); + sg = scatterwalk_ffwd(rctx->dst + 1, req->dst, req->assoclen); + if (sg != rctx->dst + 1) + sg_chain(rctx->dst, 2, sg); + } + + aead_request_set_tfm(subreq, child); + aead_request_set_callback(subreq, req->base.flags, req->base.complete, + req->base.data); + aead_request_set_crypt(subreq, rctx->src, + req->src == req->dst ? rctx->src : rctx->dst, + req->cryptlen, iv); + aead_request_set_ad(subreq, req->assoclen - 8); + + return subreq; +} + +static int crypto_rfc4309_encrypt(struct aead_request *req) +{ + if (req->assoclen != 16 && req->assoclen != 20) + return -EINVAL; + + req = crypto_rfc4309_crypt(req); + + return crypto_aead_encrypt(req); +} + +static int crypto_rfc4309_decrypt(struct aead_request *req) +{ + if (req->assoclen != 16 && req->assoclen != 20) + return -EINVAL; + + req = crypto_rfc4309_crypt(req); + + return crypto_aead_decrypt(req); +} + +static int crypto_rfc4309_init_tfm(struct crypto_aead *tfm) +{ + struct aead_instance *inst = aead_alg_instance(tfm); + struct crypto_aead_spawn *spawn = aead_instance_ctx(inst); + struct crypto_rfc4309_ctx *ctx = crypto_aead_ctx(tfm); + struct crypto_aead *aead; + unsigned long align; + + aead = crypto_spawn_aead(spawn); + if (IS_ERR(aead)) + return PTR_ERR(aead); + + ctx->child = aead; + + align = crypto_aead_alignmask(aead); + align &= ~(crypto_tfm_ctx_alignment() - 1); + crypto_aead_set_reqsize( + tfm, + sizeof(struct crypto_rfc4309_req_ctx) + + ALIGN(crypto_aead_reqsize(aead), crypto_tfm_ctx_alignment()) + + align + 32); + + return 0; +} + +static void crypto_rfc4309_exit_tfm(struct crypto_aead *tfm) +{ + struct crypto_rfc4309_ctx *ctx = crypto_aead_ctx(tfm); + + crypto_free_aead(ctx->child); +} + +static void crypto_rfc4309_free(struct aead_instance *inst) +{ + crypto_drop_aead(aead_instance_ctx(inst)); + kfree(inst); +} + +static int crypto_rfc4309_create(struct crypto_template *tmpl, + struct rtattr **tb) +{ + struct crypto_attr_type *algt; + struct aead_instance *inst; + struct crypto_aead_spawn *spawn; + struct aead_alg *alg; + const char *ccm_name; + int err; + + algt = crypto_get_attr_type(tb); + if (IS_ERR(algt)) + return PTR_ERR(algt); + + if ((algt->type ^ CRYPTO_ALG_TYPE_AEAD) & algt->mask) + return -EINVAL; + + ccm_name = crypto_attr_alg_name(tb[1]); + if (IS_ERR(ccm_name)) + return PTR_ERR(ccm_name); + + inst = kzalloc(sizeof(*inst) + sizeof(*spawn), GFP_KERNEL); + if (!inst) + return -ENOMEM; + + spawn = aead_instance_ctx(inst); + crypto_set_aead_spawn(spawn, aead_crypto_instance(inst)); + err = crypto_grab_aead(spawn, ccm_name, 0, + crypto_requires_sync(algt->type, algt->mask)); + if (err) + goto out_free_inst; + + alg = crypto_spawn_aead_alg(spawn); + + err = -EINVAL; + + /* We only support 16-byte blocks. */ + if (crypto_aead_alg_ivsize(alg) != 16) + goto out_drop_alg; + + /* Not a stream cipher? */ + if (alg->base.cra_blocksize != 1) + goto out_drop_alg; + + err = -ENAMETOOLONG; + if (snprintf(inst->alg.base.cra_name, CRYPTO_MAX_ALG_NAME, + "rfc4309(%s)", alg->base.cra_name) >= + CRYPTO_MAX_ALG_NAME || + snprintf(inst->alg.base.cra_driver_name, CRYPTO_MAX_ALG_NAME, + "rfc4309(%s)", alg->base.cra_driver_name) >= + CRYPTO_MAX_ALG_NAME) + goto out_drop_alg; + + inst->alg.base.cra_flags = alg->base.cra_flags & CRYPTO_ALG_ASYNC; + inst->alg.base.cra_priority = alg->base.cra_priority; + inst->alg.base.cra_blocksize = 1; + inst->alg.base.cra_alignmask = alg->base.cra_alignmask; + + inst->alg.ivsize = 8; + inst->alg.chunksize = crypto_aead_alg_chunksize(alg); + inst->alg.maxauthsize = 16; + + inst->alg.base.cra_ctxsize = sizeof(struct crypto_rfc4309_ctx); + + inst->alg.init = crypto_rfc4309_init_tfm; + inst->alg.exit = crypto_rfc4309_exit_tfm; + + inst->alg.setkey = crypto_rfc4309_setkey; + inst->alg.setauthsize = crypto_rfc4309_setauthsize; + inst->alg.encrypt = crypto_rfc4309_encrypt; + inst->alg.decrypt = crypto_rfc4309_decrypt; + + inst->free = crypto_rfc4309_free; + + err = aead_register_instance(tmpl, inst); + if (err) + goto out_drop_alg; + +out: + return err; + +out_drop_alg: + crypto_drop_aead(spawn); +out_free_inst: + kfree(inst); + goto out; +} + +static struct crypto_template crypto_rfc4309_tmpl = { + .name = "rfc4309", + .create = crypto_rfc4309_create, + .module = THIS_MODULE, +}; + +static int crypto_cbcmac_digest_setkey(struct crypto_shash *parent, + const u8 *inkey, unsigned int keylen) +{ + struct cbcmac_tfm_ctx *ctx = crypto_shash_ctx(parent); + + return crypto_cipher_setkey(ctx->child, inkey, keylen); +} + +static int crypto_cbcmac_digest_init(struct shash_desc *pdesc) +{ + struct cbcmac_desc_ctx *ctx = shash_desc_ctx(pdesc); + int bs = crypto_shash_digestsize(pdesc->tfm); + u8 *dg = (u8 *)ctx + crypto_shash_descsize(pdesc->tfm) - bs; + + ctx->len = 0; + memset(dg, 0, bs); + + return 0; +} + +static int crypto_cbcmac_digest_update(struct shash_desc *pdesc, const u8 *p, + unsigned int len) +{ + struct crypto_shash *parent = pdesc->tfm; + struct cbcmac_tfm_ctx *tctx = crypto_shash_ctx(parent); + struct cbcmac_desc_ctx *ctx = shash_desc_ctx(pdesc); + struct crypto_cipher *tfm = tctx->child; + int bs = crypto_shash_digestsize(parent); + u8 *dg = (u8 *)ctx + crypto_shash_descsize(parent) - bs; + + while (len > 0) { + unsigned int l = min(len, bs - ctx->len); + + crypto_xor(dg + ctx->len, p, l); + ctx->len +=l; + len -= l; + p += l; + + if (ctx->len == bs) { + crypto_cipher_encrypt_one(tfm, dg, dg); + ctx->len = 0; + } + } + + return 0; +} + +static int crypto_cbcmac_digest_final(struct shash_desc *pdesc, u8 *out) +{ + struct crypto_shash *parent = pdesc->tfm; + struct cbcmac_tfm_ctx *tctx = crypto_shash_ctx(parent); + struct cbcmac_desc_ctx *ctx = shash_desc_ctx(pdesc); + struct crypto_cipher *tfm = tctx->child; + int bs = crypto_shash_digestsize(parent); + u8 *dg = (u8 *)ctx + crypto_shash_descsize(parent) - bs; + + if (ctx->len) + crypto_cipher_encrypt_one(tfm, dg, dg); + + memcpy(out, dg, bs); + return 0; +} + +static int cbcmac_init_tfm(struct crypto_tfm *tfm) +{ + struct crypto_cipher *cipher; + struct crypto_instance *inst = (void *)tfm->__crt_alg; + struct crypto_spawn *spawn = crypto_instance_ctx(inst); + struct cbcmac_tfm_ctx *ctx = crypto_tfm_ctx(tfm); + + cipher = crypto_spawn_cipher(spawn); + if (IS_ERR(cipher)) + return PTR_ERR(cipher); + + ctx->child = cipher; + + return 0; +}; + +static void cbcmac_exit_tfm(struct crypto_tfm *tfm) +{ + struct cbcmac_tfm_ctx *ctx = crypto_tfm_ctx(tfm); + crypto_free_cipher(ctx->child); +} + +static int cbcmac_create(struct crypto_template *tmpl, struct rtattr **tb) +{ + struct shash_instance *inst; + struct crypto_alg *alg; + int err; + + err = crypto_check_attr_type(tb, CRYPTO_ALG_TYPE_SHASH); + if (err) + return err; + + alg = crypto_get_attr_alg(tb, CRYPTO_ALG_TYPE_CIPHER, + CRYPTO_ALG_TYPE_MASK); + if (IS_ERR(alg)) + return PTR_ERR(alg); + + inst = shash_alloc_instance("cbcmac", alg); + err = PTR_ERR(inst); + if (IS_ERR(inst)) + goto out_put_alg; + + err = crypto_init_spawn(shash_instance_ctx(inst), alg, + shash_crypto_instance(inst), + CRYPTO_ALG_TYPE_MASK); + if (err) + goto out_free_inst; + + inst->alg.base.cra_priority = alg->cra_priority; + inst->alg.base.cra_blocksize = 1; + + inst->alg.digestsize = alg->cra_blocksize; + inst->alg.descsize = ALIGN(sizeof(struct cbcmac_desc_ctx), + alg->cra_alignmask + 1) + + alg->cra_blocksize; + + inst->alg.base.cra_ctxsize = sizeof(struct cbcmac_tfm_ctx); + inst->alg.base.cra_init = cbcmac_init_tfm; + inst->alg.base.cra_exit = cbcmac_exit_tfm; + + inst->alg.init = crypto_cbcmac_digest_init; + inst->alg.update = crypto_cbcmac_digest_update; + inst->alg.final = crypto_cbcmac_digest_final; + inst->alg.setkey = crypto_cbcmac_digest_setkey; + + err = shash_register_instance(tmpl, inst); + +out_free_inst: + if (err) + shash_free_instance(shash_crypto_instance(inst)); + +out_put_alg: + crypto_mod_put(alg); + return err; +} + +static struct crypto_template crypto_cbcmac_tmpl = { + .name = "cbcmac", + .create = cbcmac_create, + .free = shash_free_instance, + .module = THIS_MODULE, +}; + +static int __init crypto_ccm_module_init(void) +{ + int err; + + err = crypto_register_template(&crypto_cbcmac_tmpl); + if (err) + goto out; + + err = crypto_register_template(&crypto_ccm_base_tmpl); + if (err) + goto out_undo_cbcmac; + + err = crypto_register_template(&crypto_ccm_tmpl); + if (err) + goto out_undo_base; + + err = crypto_register_template(&crypto_rfc4309_tmpl); + if (err) + goto out_undo_ccm; + +out: + return err; + +out_undo_ccm: + crypto_unregister_template(&crypto_ccm_tmpl); +out_undo_base: + crypto_unregister_template(&crypto_ccm_base_tmpl); +out_undo_cbcmac: + crypto_register_template(&crypto_cbcmac_tmpl); + goto out; +} + +static void __exit crypto_ccm_module_exit(void) +{ + crypto_unregister_template(&crypto_rfc4309_tmpl); + crypto_unregister_template(&crypto_ccm_tmpl); + crypto_unregister_template(&crypto_ccm_base_tmpl); + crypto_unregister_template(&crypto_cbcmac_tmpl); +} + +module_init(crypto_ccm_module_init); +module_exit(crypto_ccm_module_exit); + +MODULE_LICENSE("GPL"); +MODULE_DESCRIPTION("Counter with CBC MAC"); +MODULE_ALIAS_CRYPTO("ccm_base"); +MODULE_ALIAS_CRYPTO("rfc4309"); +MODULE_ALIAS_CRYPTO("ccm"); |