| /* |
| * 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/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_spawn cipher; |
| }; |
| |
| struct crypto_ccm_ctx { |
| struct crypto_cipher *cipher; |
| struct crypto_ablkcipher *ctr; |
| }; |
| |
| struct crypto_rfc4309_ctx { |
| struct crypto_aead *child; |
| u8 nonce[3]; |
| }; |
| |
| struct crypto_ccm_req_priv_ctx { |
| u8 odata[16]; |
| u8 idata[16]; |
| u8 auth_tag[16]; |
| u32 ilen; |
| u32 flags; |
| struct scatterlist src[2]; |
| struct scatterlist dst[2]; |
| struct ablkcipher_request abreq; |
| }; |
| |
| 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_ablkcipher *ctr = ctx->ctr; |
| struct crypto_cipher *tfm = ctx->cipher; |
| int err = 0; |
| |
| crypto_ablkcipher_clear_flags(ctr, CRYPTO_TFM_REQ_MASK); |
| crypto_ablkcipher_set_flags(ctr, crypto_aead_get_flags(aead) & |
| CRYPTO_TFM_REQ_MASK); |
| err = crypto_ablkcipher_setkey(ctr, key, keylen); |
| crypto_aead_set_flags(aead, crypto_ablkcipher_get_flags(ctr) & |
| CRYPTO_TFM_RES_MASK); |
| if (err) |
| goto out; |
| |
| crypto_cipher_clear_flags(tfm, CRYPTO_TFM_REQ_MASK); |
| crypto_cipher_set_flags(tfm, crypto_aead_get_flags(aead) & |
| CRYPTO_TFM_REQ_MASK); |
| err = crypto_cipher_setkey(tfm, key, keylen); |
| crypto_aead_set_flags(aead, crypto_cipher_get_flags(tfm) & |
| 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 void compute_mac(struct crypto_cipher *tfm, u8 *data, int n, |
| struct crypto_ccm_req_priv_ctx *pctx) |
| { |
| unsigned int bs = 16; |
| u8 *odata = pctx->odata; |
| u8 *idata = pctx->idata; |
| int datalen, getlen; |
| |
| datalen = n; |
| |
| /* first time in here, block may be partially filled. */ |
| getlen = bs - pctx->ilen; |
| if (datalen >= getlen) { |
| memcpy(idata + pctx->ilen, data, getlen); |
| crypto_xor(odata, idata, bs); |
| crypto_cipher_encrypt_one(tfm, odata, odata); |
| datalen -= getlen; |
| data += getlen; |
| pctx->ilen = 0; |
| } |
| |
| /* now encrypt rest of data */ |
| while (datalen >= bs) { |
| crypto_xor(odata, data, bs); |
| crypto_cipher_encrypt_one(tfm, odata, odata); |
| |
| datalen -= bs; |
| data += bs; |
| } |
| |
| /* check and see if there's leftover data that wasn't |
| * enough to fill a block. |
| */ |
| if (datalen) { |
| memcpy(idata + pctx->ilen, data, datalen); |
| pctx->ilen += datalen; |
| } |
| } |
| |
| static void get_data_to_compute(struct crypto_cipher *tfm, |
| struct crypto_ccm_req_priv_ctx *pctx, |
| struct scatterlist *sg, unsigned int len) |
| { |
| struct scatter_walk walk; |
| u8 *data_src; |
| int n; |
| |
| scatterwalk_start(&walk, sg); |
| |
| while (len) { |
| n = scatterwalk_clamp(&walk, len); |
| if (!n) { |
| scatterwalk_start(&walk, sg_next(walk.sg)); |
| n = scatterwalk_clamp(&walk, len); |
| } |
| data_src = scatterwalk_map(&walk); |
| |
| compute_mac(tfm, data_src, n, pctx); |
| len -= n; |
| |
| scatterwalk_unmap(data_src); |
| scatterwalk_advance(&walk, n); |
| scatterwalk_done(&walk, 0, len); |
| if (len) |
| crypto_yield(pctx->flags); |
| } |
| |
| /* any leftover needs padding and then encrypted */ |
| if (pctx->ilen) { |
| int padlen; |
| u8 *odata = pctx->odata; |
| u8 *idata = pctx->idata; |
| |
| padlen = 16 - pctx->ilen; |
| memset(idata + pctx->ilen, 0, padlen); |
| crypto_xor(odata, idata, 16); |
| crypto_cipher_encrypt_one(tfm, odata, odata); |
| pctx->ilen = 0; |
| } |
| } |
| |
| static int crypto_ccm_auth(struct aead_request *req, struct scatterlist *plain, |
| unsigned int cryptlen) |
| { |
| 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 crypto_cipher *cipher = ctx->cipher; |
| unsigned int assoclen = req->assoclen; |
| u8 *odata = pctx->odata; |
| u8 *idata = pctx->idata; |
| int err; |
| |
| /* format control data for input */ |
| err = format_input(odata, req, cryptlen); |
| if (err) |
| goto out; |
| |
| /* encrypt first block to use as start in computing mac */ |
| crypto_cipher_encrypt_one(cipher, odata, odata); |
| |
| /* format associated data and compute into mac */ |
| if (assoclen) { |
| pctx->ilen = format_adata(idata, assoclen); |
| get_data_to_compute(cipher, pctx, req->assoc, req->assoclen); |
| } else { |
| pctx->ilen = 0; |
| } |
| |
| /* compute plaintext into mac */ |
| if (cryptlen) |
| get_data_to_compute(cipher, pctx, plain, cryptlen); |
| |
| 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->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_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 ablkcipher_request *abreq = &pctx->abreq; |
| struct scatterlist *dst; |
| unsigned int cryptlen = req->cryptlen; |
| u8 *odata = pctx->odata; |
| u8 *iv = req->iv; |
| int err; |
| |
| err = crypto_ccm_check_iv(iv); |
| if (err) |
| return err; |
| |
| pctx->flags = aead_request_flags(req); |
| |
| err = crypto_ccm_auth(req, req->src, cryptlen); |
| if (err) |
| return err; |
| |
| /* 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, 2); |
| sg_set_buf(pctx->src, odata, 16); |
| scatterwalk_sg_chain(pctx->src, 2, req->src); |
| |
| dst = pctx->src; |
| if (req->src != req->dst) { |
| sg_init_table(pctx->dst, 2); |
| sg_set_buf(pctx->dst, odata, 16); |
| scatterwalk_sg_chain(pctx->dst, 2, req->dst); |
| dst = pctx->dst; |
| } |
| |
| ablkcipher_request_set_tfm(abreq, ctx->ctr); |
| ablkcipher_request_set_callback(abreq, pctx->flags, |
| crypto_ccm_encrypt_done, req); |
| ablkcipher_request_set_crypt(abreq, pctx->src, dst, cryptlen + 16, iv); |
| err = crypto_ablkcipher_encrypt(abreq); |
| if (err) |
| return err; |
| |
| /* copy authtag to end of dst */ |
| scatterwalk_map_and_copy(odata, req->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; |
| |
| if (!err) { |
| err = crypto_ccm_auth(req, req->dst, cryptlen); |
| if (!err && memcmp(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 ablkcipher_request *abreq = &pctx->abreq; |
| 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 = req->iv; |
| int err; |
| |
| if (cryptlen < authsize) |
| return -EINVAL; |
| cryptlen -= authsize; |
| |
| err = crypto_ccm_check_iv(iv); |
| if (err) |
| return err; |
| |
| pctx->flags = aead_request_flags(req); |
| |
| scatterwalk_map_and_copy(authtag, req->src, cryptlen, authsize, 0); |
| |
| memset(iv + 15 - iv[0], 0, iv[0] + 1); |
| |
| sg_init_table(pctx->src, 2); |
| sg_set_buf(pctx->src, authtag, 16); |
| scatterwalk_sg_chain(pctx->src, 2, req->src); |
| |
| dst = pctx->src; |
| if (req->src != req->dst) { |
| sg_init_table(pctx->dst, 2); |
| sg_set_buf(pctx->dst, authtag, 16); |
| scatterwalk_sg_chain(pctx->dst, 2, req->dst); |
| dst = pctx->dst; |
| } |
| |
| ablkcipher_request_set_tfm(abreq, ctx->ctr); |
| ablkcipher_request_set_callback(abreq, pctx->flags, |
| crypto_ccm_decrypt_done, req); |
| ablkcipher_request_set_crypt(abreq, pctx->src, dst, cryptlen + 16, iv); |
| err = crypto_ablkcipher_decrypt(abreq); |
| if (err) |
| return err; |
| |
| err = crypto_ccm_auth(req, req->dst, cryptlen); |
| if (err) |
| return err; |
| |
| /* verify */ |
| if (memcmp(authtag, odata, authsize)) |
| return -EBADMSG; |
| |
| return err; |
| } |
| |
| static int crypto_ccm_init_tfm(struct crypto_tfm *tfm) |
| { |
| struct crypto_instance *inst = (void *)tfm->__crt_alg; |
| struct ccm_instance_ctx *ictx = crypto_instance_ctx(inst); |
| struct crypto_ccm_ctx *ctx = crypto_tfm_ctx(tfm); |
| struct crypto_cipher *cipher; |
| struct crypto_ablkcipher *ctr; |
| unsigned long align; |
| int err; |
| |
| cipher = crypto_spawn_cipher(&ictx->cipher); |
| if (IS_ERR(cipher)) |
| return PTR_ERR(cipher); |
| |
| ctr = crypto_spawn_skcipher(&ictx->ctr); |
| err = PTR_ERR(ctr); |
| if (IS_ERR(ctr)) |
| goto err_free_cipher; |
| |
| ctx->cipher = cipher; |
| ctx->ctr = ctr; |
| |
| align = crypto_tfm_alg_alignmask(tfm); |
| align &= ~(crypto_tfm_ctx_alignment() - 1); |
| tfm->crt_aead.reqsize = align + |
| sizeof(struct crypto_ccm_req_priv_ctx) + |
| crypto_ablkcipher_reqsize(ctr); |
| |
| return 0; |
| |
| err_free_cipher: |
| crypto_free_cipher(cipher); |
| return err; |
| } |
| |
| static void crypto_ccm_exit_tfm(struct crypto_tfm *tfm) |
| { |
| struct crypto_ccm_ctx *ctx = crypto_tfm_ctx(tfm); |
| |
| crypto_free_cipher(ctx->cipher); |
| crypto_free_ablkcipher(ctx->ctr); |
| } |
| |
| static struct crypto_instance *crypto_ccm_alloc_common(struct rtattr **tb, |
| const char *full_name, |
| const char *ctr_name, |
| const char *cipher_name) |
| { |
| struct crypto_attr_type *algt; |
| struct crypto_instance *inst; |
| struct crypto_alg *ctr; |
| struct crypto_alg *cipher; |
| struct ccm_instance_ctx *ictx; |
| int err; |
| |
| algt = crypto_get_attr_type(tb); |
| if (IS_ERR(algt)) |
| return ERR_CAST(algt); |
| |
| if ((algt->type ^ CRYPTO_ALG_TYPE_AEAD) & algt->mask) |
| return ERR_PTR(-EINVAL); |
| |
| cipher = crypto_alg_mod_lookup(cipher_name, CRYPTO_ALG_TYPE_CIPHER, |
| CRYPTO_ALG_TYPE_MASK); |
| if (IS_ERR(cipher)) |
| return ERR_CAST(cipher); |
| |
| err = -EINVAL; |
| if (cipher->cra_blocksize != 16) |
| goto out_put_cipher; |
| |
| inst = kzalloc(sizeof(*inst) + sizeof(*ictx), GFP_KERNEL); |
| err = -ENOMEM; |
| if (!inst) |
| goto out_put_cipher; |
| |
| ictx = crypto_instance_ctx(inst); |
| |
| err = crypto_init_spawn(&ictx->cipher, cipher, inst, |
| CRYPTO_ALG_TYPE_MASK); |
| if (err) |
| goto err_free_inst; |
| |
| crypto_set_skcipher_spawn(&ictx->ctr, inst); |
| err = crypto_grab_skcipher(&ictx->ctr, ctr_name, 0, |
| crypto_requires_sync(algt->type, |
| algt->mask)); |
| if (err) |
| goto err_drop_cipher; |
| |
| ctr = crypto_skcipher_spawn_alg(&ictx->ctr); |
| |
| /* Not a stream cipher? */ |
| err = -EINVAL; |
| if (ctr->cra_blocksize != 1) |
| goto err_drop_ctr; |
| |
| /* We want the real thing! */ |
| if (ctr->cra_ablkcipher.ivsize != 16) |
| goto err_drop_ctr; |
| |
| err = -ENAMETOOLONG; |
| if (snprintf(inst->alg.cra_driver_name, CRYPTO_MAX_ALG_NAME, |
| "ccm_base(%s,%s)", ctr->cra_driver_name, |
| cipher->cra_driver_name) >= CRYPTO_MAX_ALG_NAME) |
| goto err_drop_ctr; |
| |
| memcpy(inst->alg.cra_name, full_name, CRYPTO_MAX_ALG_NAME); |
| |
| inst->alg.cra_flags = CRYPTO_ALG_TYPE_AEAD; |
| inst->alg.cra_flags |= ctr->cra_flags & CRYPTO_ALG_ASYNC; |
| inst->alg.cra_priority = cipher->cra_priority + ctr->cra_priority; |
| inst->alg.cra_blocksize = 1; |
| inst->alg.cra_alignmask = cipher->cra_alignmask | ctr->cra_alignmask | |
| (__alignof__(u32) - 1); |
| inst->alg.cra_type = &crypto_aead_type; |
| inst->alg.cra_aead.ivsize = 16; |
| inst->alg.cra_aead.maxauthsize = 16; |
| inst->alg.cra_ctxsize = sizeof(struct crypto_ccm_ctx); |
| inst->alg.cra_init = crypto_ccm_init_tfm; |
| inst->alg.cra_exit = crypto_ccm_exit_tfm; |
| inst->alg.cra_aead.setkey = crypto_ccm_setkey; |
| inst->alg.cra_aead.setauthsize = crypto_ccm_setauthsize; |
| inst->alg.cra_aead.encrypt = crypto_ccm_encrypt; |
| inst->alg.cra_aead.decrypt = crypto_ccm_decrypt; |
| |
| out: |
| crypto_mod_put(cipher); |
| return inst; |
| |
| err_drop_ctr: |
| crypto_drop_skcipher(&ictx->ctr); |
| err_drop_cipher: |
| crypto_drop_spawn(&ictx->cipher); |
| err_free_inst: |
| kfree(inst); |
| out_put_cipher: |
| inst = ERR_PTR(err); |
| goto out; |
| } |
| |
| static struct crypto_instance *crypto_ccm_alloc(struct rtattr **tb) |
| { |
| const char *cipher_name; |
| char ctr_name[CRYPTO_MAX_ALG_NAME]; |
| char full_name[CRYPTO_MAX_ALG_NAME]; |
| |
| cipher_name = crypto_attr_alg_name(tb[1]); |
| if (IS_ERR(cipher_name)) |
| return ERR_CAST(cipher_name); |
| |
| if (snprintf(ctr_name, CRYPTO_MAX_ALG_NAME, "ctr(%s)", |
| cipher_name) >= CRYPTO_MAX_ALG_NAME) |
| return ERR_PTR(-ENAMETOOLONG); |
| |
| if (snprintf(full_name, CRYPTO_MAX_ALG_NAME, "ccm(%s)", cipher_name) >= |
| CRYPTO_MAX_ALG_NAME) |
| return ERR_PTR(-ENAMETOOLONG); |
| |
| return crypto_ccm_alloc_common(tb, full_name, ctr_name, cipher_name); |
| } |
| |
| static void crypto_ccm_free(struct crypto_instance *inst) |
| { |
| struct ccm_instance_ctx *ctx = crypto_instance_ctx(inst); |
| |
| crypto_drop_spawn(&ctx->cipher); |
| crypto_drop_skcipher(&ctx->ctr); |
| kfree(inst); |
| } |
| |
| static struct crypto_template crypto_ccm_tmpl = { |
| .name = "ccm", |
| .alloc = crypto_ccm_alloc, |
| .free = crypto_ccm_free, |
| .module = THIS_MODULE, |
| }; |
| |
| static struct crypto_instance *crypto_ccm_base_alloc(struct rtattr **tb) |
| { |
| const char *ctr_name; |
| const char *cipher_name; |
| char full_name[CRYPTO_MAX_ALG_NAME]; |
| |
| ctr_name = crypto_attr_alg_name(tb[1]); |
| if (IS_ERR(ctr_name)) |
| return ERR_CAST(ctr_name); |
| |
| cipher_name = crypto_attr_alg_name(tb[2]); |
| if (IS_ERR(cipher_name)) |
| return ERR_CAST(cipher_name); |
| |
| if (snprintf(full_name, CRYPTO_MAX_ALG_NAME, "ccm_base(%s,%s)", |
| ctr_name, cipher_name) >= CRYPTO_MAX_ALG_NAME) |
| return ERR_PTR(-ENAMETOOLONG); |
| |
| return crypto_ccm_alloc_common(tb, full_name, ctr_name, cipher_name); |
| } |
| |
| static struct crypto_template crypto_ccm_base_tmpl = { |
| .name = "ccm_base", |
| .alloc = crypto_ccm_base_alloc, |
| .free = crypto_ccm_free, |
| .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 aead_request *subreq = aead_request_ctx(req); |
| struct crypto_aead *aead = crypto_aead_reqtfm(req); |
| struct crypto_rfc4309_ctx *ctx = crypto_aead_ctx(aead); |
| struct crypto_aead *child = ctx->child; |
| 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); |
| |
| 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, req->src, req->dst, req->cryptlen, iv); |
| aead_request_set_assoc(subreq, req->assoc, req->assoclen); |
| |
| return subreq; |
| } |
| |
| static int crypto_rfc4309_encrypt(struct aead_request *req) |
| { |
| req = crypto_rfc4309_crypt(req); |
| |
| return crypto_aead_encrypt(req); |
| } |
| |
| static int crypto_rfc4309_decrypt(struct aead_request *req) |
| { |
| req = crypto_rfc4309_crypt(req); |
| |
| return crypto_aead_decrypt(req); |
| } |
| |
| static int crypto_rfc4309_init_tfm(struct crypto_tfm *tfm) |
| { |
| struct crypto_instance *inst = (void *)tfm->__crt_alg; |
| struct crypto_aead_spawn *spawn = crypto_instance_ctx(inst); |
| struct crypto_rfc4309_ctx *ctx = crypto_tfm_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); |
| tfm->crt_aead.reqsize = sizeof(struct aead_request) + |
| ALIGN(crypto_aead_reqsize(aead), |
| crypto_tfm_ctx_alignment()) + |
| align + 16; |
| |
| return 0; |
| } |
| |
| static void crypto_rfc4309_exit_tfm(struct crypto_tfm *tfm) |
| { |
| struct crypto_rfc4309_ctx *ctx = crypto_tfm_ctx(tfm); |
| |
| crypto_free_aead(ctx->child); |
| } |
| |
| static struct crypto_instance *crypto_rfc4309_alloc(struct rtattr **tb) |
| { |
| struct crypto_attr_type *algt; |
| struct crypto_instance *inst; |
| struct crypto_aead_spawn *spawn; |
| struct crypto_alg *alg; |
| const char *ccm_name; |
| int err; |
| |
| algt = crypto_get_attr_type(tb); |
| if (IS_ERR(algt)) |
| return ERR_CAST(algt); |
| |
| if ((algt->type ^ CRYPTO_ALG_TYPE_AEAD) & algt->mask) |
| return ERR_PTR(-EINVAL); |
| |
| ccm_name = crypto_attr_alg_name(tb[1]); |
| if (IS_ERR(ccm_name)) |
| return ERR_CAST(ccm_name); |
| |
| inst = kzalloc(sizeof(*inst) + sizeof(*spawn), GFP_KERNEL); |
| if (!inst) |
| return ERR_PTR(-ENOMEM); |
| |
| spawn = crypto_instance_ctx(inst); |
| crypto_set_aead_spawn(spawn, inst); |
| err = crypto_grab_aead(spawn, ccm_name, 0, |
| crypto_requires_sync(algt->type, algt->mask)); |
| if (err) |
| goto out_free_inst; |
| |
| alg = crypto_aead_spawn_alg(spawn); |
| |
| err = -EINVAL; |
| |
| /* We only support 16-byte blocks. */ |
| if (alg->cra_aead.ivsize != 16) |
| goto out_drop_alg; |
| |
| /* Not a stream cipher? */ |
| if (alg->cra_blocksize != 1) |
| goto out_drop_alg; |
| |
| err = -ENAMETOOLONG; |
| if (snprintf(inst->alg.cra_name, CRYPTO_MAX_ALG_NAME, |
| "rfc4309(%s)", alg->cra_name) >= CRYPTO_MAX_ALG_NAME || |
| snprintf(inst->alg.cra_driver_name, CRYPTO_MAX_ALG_NAME, |
| "rfc4309(%s)", alg->cra_driver_name) >= |
| CRYPTO_MAX_ALG_NAME) |
| goto out_drop_alg; |
| |
| inst->alg.cra_flags = CRYPTO_ALG_TYPE_AEAD; |
| inst->alg.cra_flags |= alg->cra_flags & CRYPTO_ALG_ASYNC; |
| inst->alg.cra_priority = alg->cra_priority; |
| inst->alg.cra_blocksize = 1; |
| inst->alg.cra_alignmask = alg->cra_alignmask; |
| inst->alg.cra_type = &crypto_nivaead_type; |
| |
| inst->alg.cra_aead.ivsize = 8; |
| inst->alg.cra_aead.maxauthsize = 16; |
| |
| inst->alg.cra_ctxsize = sizeof(struct crypto_rfc4309_ctx); |
| |
| inst->alg.cra_init = crypto_rfc4309_init_tfm; |
| inst->alg.cra_exit = crypto_rfc4309_exit_tfm; |
| |
| inst->alg.cra_aead.setkey = crypto_rfc4309_setkey; |
| inst->alg.cra_aead.setauthsize = crypto_rfc4309_setauthsize; |
| inst->alg.cra_aead.encrypt = crypto_rfc4309_encrypt; |
| inst->alg.cra_aead.decrypt = crypto_rfc4309_decrypt; |
| |
| inst->alg.cra_aead.geniv = "seqiv"; |
| |
| out: |
| return inst; |
| |
| out_drop_alg: |
| crypto_drop_aead(spawn); |
| out_free_inst: |
| kfree(inst); |
| inst = ERR_PTR(err); |
| goto out; |
| } |
| |
| static void crypto_rfc4309_free(struct crypto_instance *inst) |
| { |
| crypto_drop_spawn(crypto_instance_ctx(inst)); |
| kfree(inst); |
| } |
| |
| static struct crypto_template crypto_rfc4309_tmpl = { |
| .name = "rfc4309", |
| .alloc = crypto_rfc4309_alloc, |
| .free = crypto_rfc4309_free, |
| .module = THIS_MODULE, |
| }; |
| |
| static int __init crypto_ccm_module_init(void) |
| { |
| int err; |
| |
| err = crypto_register_template(&crypto_ccm_base_tmpl); |
| if (err) |
| goto out; |
| |
| 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); |
| 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); |
| } |
| |
| module_init(crypto_ccm_module_init); |
| module_exit(crypto_ccm_module_exit); |
| |
| MODULE_LICENSE("GPL"); |
| MODULE_DESCRIPTION("Counter with CBC MAC"); |
| MODULE_ALIAS("ccm_base"); |
| MODULE_ALIAS("rfc4309"); |