diff options
| author | Kumar Kartikeya Dwivedi <memxor@gmail.com> | 2026-09-04 10:43:19 +0200 |
|---|---|---|
| committer | Alexei Starovoitov <ast@kernel.org> | 2026-09-04 07:58:36 -0700 |
| commit | 6668ed271eaefaa63e686bdfbedaeb7b8e492722 (patch) | |
| tree | 58e8288fead484f6755ad0815fc74c3742663761 /crypto/gcm.c | |
| download | linux-stable-6668ed271eaefaa63e686bdfbedaeb7b8e492722.tar.gz linux-stable-6668ed271eaefaa63e686bdfbedaeb7b8e492722.zip | |
selftests/bpf: Reject graph kptr use after RCU unlockgrafted
Add a sleepable verifier test that loads a graph-node local kptr in an
explicit RCU read-side critical section, then passes its node to
bpf_rbtree_remove() after the section ends.
Before the verifier fix, the stale NON_OWN_REF flag makes the node look like
a live borrowed reference and the program is accepted. After the fix, the
pointer is demoted without NON_OWN_REF and the graph kfunc argument is
rejected.
Also exercise a graph kptr loaded while a spin lock provides implicit RCU
protection. The pointer must be invalidated when the lock is released, which
guards the required ordering between non-owning-reference invalidation and
RCU demotion.
Update the existing fault-protected load test state description. The
post-unlock pointer no longer carries NON_OWN_REF, but remains readable
because the load is rewritten to use BPF_PROBE_MEM.
Signed-off-by: Kumar Kartikeya Dwivedi <memxor@gmail.com>
Link: https://lore.kernel.org/r/20260904084325.52250-7-memxor@gmail.com
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Diffstat (limited to 'crypto/gcm.c')
| -rw-r--r-- | crypto/gcm.c | 874 |
1 files changed, 874 insertions, 0 deletions
diff --git a/crypto/gcm.c b/crypto/gcm.c new file mode 100644 index 000000000..5f16b237b --- /dev/null +++ b/crypto/gcm.c @@ -0,0 +1,874 @@ +// SPDX-License-Identifier: GPL-2.0-only +/* + * GCM: Galois/Counter Mode. + * + * Copyright (c) 2007 Nokia Siemens Networks - Mikko Herranen <mh1@iki.fi> + */ + +#include <crypto/internal/aead.h> +#include <crypto/internal/skcipher.h> +#include <crypto/scatterwalk.h> +#include <crypto/gcm.h> +#include <crypto/gf128hash.h> +#include <linux/err.h> +#include <linux/init.h> +#include <linux/kernel.h> +#include <linux/module.h> +#include <linux/slab.h> + +struct gcm_instance_ctx { + struct crypto_skcipher_spawn ctr; +}; + +struct crypto_gcm_ctx { + struct crypto_skcipher *ctr; + struct ghash_key ghash; +}; + +struct crypto_rfc4106_ctx { + struct crypto_aead *child; + u8 nonce[4]; +}; + +struct crypto_rfc4106_req_ctx { + struct scatterlist src[3]; + struct scatterlist dst[3]; + struct aead_request subreq; +}; + +struct crypto_rfc4543_instance_ctx { + struct crypto_aead_spawn aead; +}; + +struct crypto_rfc4543_ctx { + struct crypto_aead *child; + u8 nonce[4]; +}; + +struct crypto_rfc4543_req_ctx { + struct aead_request subreq; +}; + +struct crypto_gcm_req_priv_ctx { + u8 iv[16]; + u8 auth_tag[16]; + u8 iauth_tag[16]; + struct scatterlist src[3]; + struct scatterlist dst[3]; + struct skcipher_request skreq; /* Must be last */ +}; + +static inline struct crypto_gcm_req_priv_ctx *crypto_gcm_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 crypto_gcm_setkey(struct crypto_aead *aead, const u8 *key, + unsigned int keylen) +{ + struct crypto_gcm_ctx *ctx = crypto_aead_ctx(aead); + struct crypto_skcipher *ctr = ctx->ctr; + struct { + u8 h[GHASH_BLOCK_SIZE]; + u8 iv[16]; + + struct crypto_wait wait; + + struct scatterlist sg[1]; + struct skcipher_request req; + } *data; + int err; + + 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); + if (err) + return err; + + data = kzalloc(sizeof(*data) + crypto_skcipher_reqsize(ctr), + GFP_KERNEL); + if (!data) + return -ENOMEM; + + crypto_init_wait(&data->wait); + sg_init_one(data->sg, data->h, sizeof(data->h)); + skcipher_request_set_tfm(&data->req, ctr); + skcipher_request_set_callback(&data->req, CRYPTO_TFM_REQ_MAY_SLEEP | + CRYPTO_TFM_REQ_MAY_BACKLOG, + crypto_req_done, + &data->wait); + skcipher_request_set_crypt(&data->req, data->sg, data->sg, + sizeof(data->h), data->iv); + + err = crypto_wait_req(crypto_skcipher_encrypt(&data->req), + &data->wait); + + if (err) + goto out; + + ghash_preparekey(&ctx->ghash, data->h); +out: + kfree_sensitive(data); + return err; +} + +static int crypto_gcm_setauthsize(struct crypto_aead *tfm, + unsigned int authsize) +{ + return crypto_gcm_check_authsize(authsize); +} + +static void crypto_gcm_init_common(struct aead_request *req) +{ + struct crypto_gcm_req_priv_ctx *pctx = crypto_gcm_reqctx(req); + __be32 counter = cpu_to_be32(1); + struct scatterlist *sg; + + memset(pctx->auth_tag, 0, sizeof(pctx->auth_tag)); + memcpy(pctx->iv, req->iv, GCM_AES_IV_SIZE); + memcpy(pctx->iv + GCM_AES_IV_SIZE, &counter, 4); + + sg_init_table(pctx->src, 3); + sg_set_buf(pctx->src, pctx->auth_tag, sizeof(pctx->auth_tag)); + 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, pctx->auth_tag, sizeof(pctx->auth_tag)); + sg = scatterwalk_ffwd(pctx->dst + 1, req->dst, req->assoclen); + if (sg != pctx->dst + 1) + sg_chain(pctx->dst, 2, sg); + } +} + +static void crypto_gcm_init_crypt(struct aead_request *req, + unsigned int cryptlen) +{ + struct crypto_aead *aead = crypto_aead_reqtfm(req); + struct crypto_gcm_ctx *ctx = crypto_aead_ctx(aead); + struct crypto_gcm_req_priv_ctx *pctx = crypto_gcm_reqctx(req); + struct skcipher_request *skreq = &pctx->skreq; + struct scatterlist *dst; + + dst = req->src == req->dst ? pctx->src : pctx->dst; + + skcipher_request_set_tfm(skreq, ctx->ctr); + skcipher_request_set_crypt(skreq, pctx->src, dst, + cryptlen + sizeof(pctx->auth_tag), + pctx->iv); +} + +static void ghash_update_sg_and_pad(struct ghash_ctx *ghash, + struct scatterlist *sg, unsigned int len) +{ + static const u8 zeroes[GHASH_BLOCK_SIZE]; + + if (len) { + unsigned int pad_len = -len % GHASH_BLOCK_SIZE; + struct scatter_walk walk; + + scatterwalk_start(&walk, sg); + do { + unsigned int n = scatterwalk_next(&walk, len); + + ghash_update(ghash, walk.addr, n); + scatterwalk_done_src(&walk, n); + len -= n; + } while (len); + + if (pad_len) + ghash_update(ghash, zeroes, pad_len); + } +} + +static void gcm_hash(struct aead_request *req, struct scatterlist *ctext, + unsigned int datalen, u8 out[GHASH_BLOCK_SIZE]) +{ + const struct crypto_gcm_ctx *ctx = + crypto_aead_ctx(crypto_aead_reqtfm(req)); + __be64 lengths[2] = { + cpu_to_be64(8 * (u64)req->assoclen), + cpu_to_be64(8 * (u64)datalen), + }; + struct ghash_ctx ghash; + + ghash_init(&ghash, &ctx->ghash); + + /* Associated data, then zero-padding to the next 16-byte boundary */ + ghash_update_sg_and_pad(&ghash, req->src, req->assoclen); + + /* Ciphertext, then zero-padding to the next 16-byte boundary */ + ghash_update_sg_and_pad(&ghash, ctext, datalen); + + /* Lengths block */ + ghash_update(&ghash, (const u8 *)lengths, sizeof(lengths)); + + ghash_final(&ghash, out); +} + +static int gcm_add_auth_tag(struct aead_request *req) +{ + struct crypto_aead *aead = crypto_aead_reqtfm(req); + struct crypto_gcm_req_priv_ctx *pctx = crypto_gcm_reqctx(req); + + gcm_hash(req, sg_next(req->src == req->dst ? pctx->src : pctx->dst), + req->cryptlen, pctx->iauth_tag); + crypto_xor(pctx->auth_tag, pctx->iauth_tag, 16); + memcpy_to_sglist(req->dst, req->assoclen + req->cryptlen, + pctx->auth_tag, crypto_aead_authsize(aead)); + return 0; +} + +static void gcm_encrypt_done(void *data, int err) +{ + struct aead_request *req = data; + + if (err) + goto out; + + err = gcm_add_auth_tag(req); + +out: + aead_request_complete(req, err); +} + +static int crypto_gcm_encrypt(struct aead_request *req) +{ + struct crypto_gcm_req_priv_ctx *pctx = crypto_gcm_reqctx(req); + struct skcipher_request *skreq = &pctx->skreq; + u32 flags = aead_request_flags(req); + + crypto_gcm_init_common(req); + crypto_gcm_init_crypt(req, req->cryptlen); + skcipher_request_set_callback(skreq, flags, gcm_encrypt_done, req); + + return crypto_skcipher_encrypt(skreq) ?: gcm_add_auth_tag(req); +} + +static int crypto_gcm_verify(struct aead_request *req) +{ + struct crypto_gcm_req_priv_ctx *pctx = crypto_gcm_reqctx(req); + struct crypto_aead *aead = crypto_aead_reqtfm(req); + u8 *auth_tag = pctx->auth_tag; + u8 *iauth_tag = pctx->iauth_tag; + unsigned int authsize = crypto_aead_authsize(aead); + unsigned int cryptlen = req->cryptlen - authsize; + + crypto_xor(auth_tag, iauth_tag, 16); + scatterwalk_map_and_copy(iauth_tag, req->src, + req->assoclen + cryptlen, authsize, 0); + return crypto_memneq(iauth_tag, auth_tag, authsize) ? -EBADMSG : 0; +} + +static void gcm_decrypt_done(void *data, int err) +{ + struct aead_request *req = data; + + if (!err) + err = crypto_gcm_verify(req); + + aead_request_complete(req, err); +} + +static int crypto_gcm_decrypt(struct aead_request *req) +{ + struct crypto_aead *aead = crypto_aead_reqtfm(req); + struct crypto_gcm_req_priv_ctx *pctx = crypto_gcm_reqctx(req); + struct skcipher_request *skreq = &pctx->skreq; + unsigned int datalen = req->cryptlen - crypto_aead_authsize(aead); + + crypto_gcm_init_common(req); + + gcm_hash(req, sg_next(pctx->src), datalen, pctx->iauth_tag); + + crypto_gcm_init_crypt(req, datalen); + skcipher_request_set_callback(skreq, aead_request_flags(req), + gcm_decrypt_done, req); + return crypto_skcipher_decrypt(skreq) ?: crypto_gcm_verify(req); +} + +static int crypto_gcm_init_tfm(struct crypto_aead *tfm) +{ + struct aead_instance *inst = aead_alg_instance(tfm); + struct gcm_instance_ctx *ictx = aead_instance_ctx(inst); + struct crypto_gcm_ctx *ctx = crypto_aead_ctx(tfm); + struct crypto_skcipher *ctr; + unsigned long align; + + ctr = crypto_spawn_skcipher(&ictx->ctr); + if (IS_ERR(ctr)) + return PTR_ERR(ctr); + + ctx->ctr = ctr; + + align = crypto_aead_alignmask(tfm); + align &= ~(crypto_tfm_ctx_alignment() - 1); + crypto_aead_set_reqsize(tfm, + align + sizeof(struct crypto_gcm_req_priv_ctx) + + crypto_skcipher_reqsize(ctr)); + return 0; +} + +static void crypto_gcm_exit_tfm(struct crypto_aead *tfm) +{ + struct crypto_gcm_ctx *ctx = crypto_aead_ctx(tfm); + + crypto_free_skcipher(ctx->ctr); +} + +static void crypto_gcm_free(struct aead_instance *inst) +{ + struct gcm_instance_ctx *ctx = aead_instance_ctx(inst); + + crypto_drop_skcipher(&ctx->ctr); + kfree(inst); +} + +static int crypto_gcm_create_common(struct crypto_template *tmpl, + struct rtattr **tb, const char *ctr_name) +{ + struct skcipher_alg_common *ctr; + u32 mask; + struct aead_instance *inst; + struct gcm_instance_ctx *ctx; + int err; + + err = crypto_check_attr_type(tb, CRYPTO_ALG_TYPE_AEAD, &mask); + if (err) + return err; + + inst = kzalloc(sizeof(*inst) + sizeof(*ctx), GFP_KERNEL); + if (!inst) + return -ENOMEM; + ctx = aead_instance_ctx(inst); + + err = crypto_grab_skcipher(&ctx->ctr, aead_crypto_instance(inst), + ctr_name, 0, mask); + if (err) + goto err_free_inst; + ctr = crypto_spawn_skcipher_alg_common(&ctx->ctr); + + /* The skcipher algorithm must be CTR mode, using 16-byte blocks. */ + err = -EINVAL; + if (strncmp(ctr->base.cra_name, "ctr(", 4) != 0 || + ctr->ivsize != 16 || ctr->base.cra_blocksize != 1) + goto err_free_inst; + + err = -ENAMETOOLONG; + if (snprintf(inst->alg.base.cra_name, CRYPTO_MAX_ALG_NAME, + "gcm(%s", ctr->base.cra_name + 4) >= CRYPTO_MAX_ALG_NAME) + goto err_free_inst; + + if (snprintf(inst->alg.base.cra_driver_name, CRYPTO_MAX_ALG_NAME, + "gcm_base(%s,ghash-lib)", + ctr->base.cra_driver_name) >= CRYPTO_MAX_ALG_NAME) + goto err_free_inst; + + inst->alg.base.cra_priority = ctr->base.cra_priority; + inst->alg.base.cra_blocksize = 1; + inst->alg.base.cra_alignmask = ctr->base.cra_alignmask; + inst->alg.base.cra_ctxsize = sizeof(struct crypto_gcm_ctx); + inst->alg.ivsize = GCM_AES_IV_SIZE; + inst->alg.chunksize = ctr->chunksize; + inst->alg.maxauthsize = 16; + inst->alg.init = crypto_gcm_init_tfm; + inst->alg.exit = crypto_gcm_exit_tfm; + inst->alg.setkey = crypto_gcm_setkey; + inst->alg.setauthsize = crypto_gcm_setauthsize; + inst->alg.encrypt = crypto_gcm_encrypt; + inst->alg.decrypt = crypto_gcm_decrypt; + + inst->free = crypto_gcm_free; + + err = aead_register_instance(tmpl, inst); + if (err) { +err_free_inst: + crypto_gcm_free(inst); + } + return err; +} + +static int crypto_gcm_create(struct crypto_template *tmpl, struct rtattr **tb) +{ + const char *cipher_name; + char ctr_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; + + return crypto_gcm_create_common(tmpl, tb, ctr_name); +} + +static int crypto_gcm_base_create(struct crypto_template *tmpl, + struct rtattr **tb) +{ + const char *ctr_name; + const char *ghash_name; + + ctr_name = crypto_attr_alg_name(tb[1]); + if (IS_ERR(ctr_name)) + return PTR_ERR(ctr_name); + + ghash_name = crypto_attr_alg_name(tb[2]); + if (IS_ERR(ghash_name)) + return PTR_ERR(ghash_name); + + /* + * Originally this parameter allowed requesting a specific + * implementation of GHASH. This is no longer supported. Now the best + * implementation of GHASH is just always used. + */ + if (strcmp(ghash_name, "ghash") != 0 && + strcmp(ghash_name, "ghash-lib") != 0) + return -EINVAL; + + return crypto_gcm_create_common(tmpl, tb, ctr_name); +} + +static int crypto_rfc4106_setkey(struct crypto_aead *parent, const u8 *key, + unsigned int keylen) +{ + struct crypto_rfc4106_ctx *ctx = crypto_aead_ctx(parent); + struct crypto_aead *child = ctx->child; + + if (keylen < 4) + return -EINVAL; + + keylen -= 4; + memcpy(ctx->nonce, key + keylen, 4); + + crypto_aead_clear_flags(child, CRYPTO_TFM_REQ_MASK); + crypto_aead_set_flags(child, crypto_aead_get_flags(parent) & + CRYPTO_TFM_REQ_MASK); + return crypto_aead_setkey(child, key, keylen); +} + +static int crypto_rfc4106_setauthsize(struct crypto_aead *parent, + unsigned int authsize) +{ + struct crypto_rfc4106_ctx *ctx = crypto_aead_ctx(parent); + int err; + + err = crypto_rfc4106_check_authsize(authsize); + if (err) + return err; + + return crypto_aead_setauthsize(ctx->child, authsize); +} + +static struct aead_request *crypto_rfc4106_crypt(struct aead_request *req) +{ + struct crypto_rfc4106_req_ctx *rctx = aead_request_ctx(req); + struct crypto_aead *aead = crypto_aead_reqtfm(req); + struct crypto_rfc4106_ctx *ctx = crypto_aead_ctx(aead); + struct aead_request *subreq = &rctx->subreq; + 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); + + scatterwalk_map_and_copy(iv + GCM_AES_IV_SIZE, req->src, 0, req->assoclen - 8, 0); + + memcpy(iv, ctx->nonce, 4); + memcpy(iv + 4, req->iv, 8); + + sg_init_table(rctx->src, 3); + sg_set_buf(rctx->src, iv + GCM_AES_IV_SIZE, 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 + GCM_AES_IV_SIZE, 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_rfc4106_encrypt(struct aead_request *req) +{ + int err; + + err = crypto_ipsec_check_assoclen(req->assoclen); + if (err) + return err; + + req = crypto_rfc4106_crypt(req); + + return crypto_aead_encrypt(req); +} + +static int crypto_rfc4106_decrypt(struct aead_request *req) +{ + int err; + + err = crypto_ipsec_check_assoclen(req->assoclen); + if (err) + return err; + + req = crypto_rfc4106_crypt(req); + + return crypto_aead_decrypt(req); +} + +static int crypto_rfc4106_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_rfc4106_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_rfc4106_req_ctx) + + ALIGN(crypto_aead_reqsize(aead), crypto_tfm_ctx_alignment()) + + align + 24); + + return 0; +} + +static void crypto_rfc4106_exit_tfm(struct crypto_aead *tfm) +{ + struct crypto_rfc4106_ctx *ctx = crypto_aead_ctx(tfm); + + crypto_free_aead(ctx->child); +} + +static void crypto_rfc4106_free(struct aead_instance *inst) +{ + crypto_drop_aead(aead_instance_ctx(inst)); + kfree(inst); +} + +static int crypto_rfc4106_create(struct crypto_template *tmpl, + struct rtattr **tb) +{ + u32 mask; + struct aead_instance *inst; + struct crypto_aead_spawn *spawn; + struct aead_alg *alg; + int err; + + err = crypto_check_attr_type(tb, CRYPTO_ALG_TYPE_AEAD, &mask); + if (err) + return err; + + inst = kzalloc(sizeof(*inst) + sizeof(*spawn), GFP_KERNEL); + if (!inst) + return -ENOMEM; + + spawn = aead_instance_ctx(inst); + err = crypto_grab_aead(spawn, aead_crypto_instance(inst), + crypto_attr_alg_name(tb[1]), 0, mask); + if (err) + goto err_free_inst; + + alg = crypto_spawn_aead_alg(spawn); + + err = -EINVAL; + + /* Underlying IV size must be 12. */ + if (crypto_aead_alg_ivsize(alg) != GCM_AES_IV_SIZE) + goto err_free_inst; + + /* Not a stream cipher? */ + if (alg->base.cra_blocksize != 1) + goto err_free_inst; + + err = -ENAMETOOLONG; + if (snprintf(inst->alg.base.cra_name, CRYPTO_MAX_ALG_NAME, + "rfc4106(%s)", alg->base.cra_name) >= + CRYPTO_MAX_ALG_NAME || + snprintf(inst->alg.base.cra_driver_name, CRYPTO_MAX_ALG_NAME, + "rfc4106(%s)", alg->base.cra_driver_name) >= + CRYPTO_MAX_ALG_NAME) + goto err_free_inst; + + 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.base.cra_ctxsize = sizeof(struct crypto_rfc4106_ctx); + + inst->alg.ivsize = GCM_RFC4106_IV_SIZE; + inst->alg.chunksize = crypto_aead_alg_chunksize(alg); + inst->alg.maxauthsize = crypto_aead_alg_maxauthsize(alg); + + inst->alg.init = crypto_rfc4106_init_tfm; + inst->alg.exit = crypto_rfc4106_exit_tfm; + + inst->alg.setkey = crypto_rfc4106_setkey; + inst->alg.setauthsize = crypto_rfc4106_setauthsize; + inst->alg.encrypt = crypto_rfc4106_encrypt; + inst->alg.decrypt = crypto_rfc4106_decrypt; + + inst->free = crypto_rfc4106_free; + + err = aead_register_instance(tmpl, inst); + if (err) { +err_free_inst: + crypto_rfc4106_free(inst); + } + return err; +} + +static int crypto_rfc4543_setkey(struct crypto_aead *parent, const u8 *key, + unsigned int keylen) +{ + struct crypto_rfc4543_ctx *ctx = crypto_aead_ctx(parent); + struct crypto_aead *child = ctx->child; + + if (keylen < 4) + return -EINVAL; + + keylen -= 4; + memcpy(ctx->nonce, key + keylen, 4); + + crypto_aead_clear_flags(child, CRYPTO_TFM_REQ_MASK); + crypto_aead_set_flags(child, crypto_aead_get_flags(parent) & + CRYPTO_TFM_REQ_MASK); + return crypto_aead_setkey(child, key, keylen); +} + +static int crypto_rfc4543_setauthsize(struct crypto_aead *parent, + unsigned int authsize) +{ + struct crypto_rfc4543_ctx *ctx = crypto_aead_ctx(parent); + + if (authsize != 16) + return -EINVAL; + + return crypto_aead_setauthsize(ctx->child, authsize); +} + +static int crypto_rfc4543_crypt(struct aead_request *req, bool enc) +{ + struct crypto_aead *aead = crypto_aead_reqtfm(req); + struct crypto_rfc4543_ctx *ctx = crypto_aead_ctx(aead); + struct crypto_rfc4543_req_ctx *rctx = aead_request_ctx(req); + struct aead_request *subreq = &rctx->subreq; + unsigned int authsize = crypto_aead_authsize(aead); + u8 *iv = PTR_ALIGN((u8 *)(rctx + 1) + crypto_aead_reqsize(ctx->child), + crypto_aead_alignmask(ctx->child) + 1); + + if (req->src != req->dst) { + unsigned int nbytes = req->assoclen + req->cryptlen - + (enc ? 0 : authsize); + + memcpy_sglist(req->dst, req->src, nbytes); + } + + memcpy(iv, ctx->nonce, 4); + memcpy(iv + 4, req->iv, 8); + + aead_request_set_tfm(subreq, ctx->child); + aead_request_set_callback(subreq, req->base.flags, + req->base.complete, req->base.data); + aead_request_set_crypt(subreq, req->src, req->dst, + enc ? 0 : authsize, iv); + aead_request_set_ad(subreq, req->assoclen + req->cryptlen - + subreq->cryptlen); + + return enc ? crypto_aead_encrypt(subreq) : crypto_aead_decrypt(subreq); +} + +static int crypto_rfc4543_encrypt(struct aead_request *req) +{ + return crypto_ipsec_check_assoclen(req->assoclen) ?: + crypto_rfc4543_crypt(req, true); +} + +static int crypto_rfc4543_decrypt(struct aead_request *req) +{ + return crypto_ipsec_check_assoclen(req->assoclen) ?: + crypto_rfc4543_crypt(req, false); +} + +static int crypto_rfc4543_init_tfm(struct crypto_aead *tfm) +{ + struct aead_instance *inst = aead_alg_instance(tfm); + struct crypto_rfc4543_instance_ctx *ictx = aead_instance_ctx(inst); + struct crypto_aead_spawn *spawn = &ictx->aead; + struct crypto_rfc4543_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_rfc4543_req_ctx) + + ALIGN(crypto_aead_reqsize(aead), crypto_tfm_ctx_alignment()) + + align + GCM_AES_IV_SIZE); + + return 0; +} + +static void crypto_rfc4543_exit_tfm(struct crypto_aead *tfm) +{ + struct crypto_rfc4543_ctx *ctx = crypto_aead_ctx(tfm); + + crypto_free_aead(ctx->child); +} + +static void crypto_rfc4543_free(struct aead_instance *inst) +{ + struct crypto_rfc4543_instance_ctx *ctx = aead_instance_ctx(inst); + + crypto_drop_aead(&ctx->aead); + + kfree(inst); +} + +static int crypto_rfc4543_create(struct crypto_template *tmpl, + struct rtattr **tb) +{ + u32 mask; + struct aead_instance *inst; + struct aead_alg *alg; + struct crypto_rfc4543_instance_ctx *ctx; + int err; + + err = crypto_check_attr_type(tb, CRYPTO_ALG_TYPE_AEAD, &mask); + if (err) + return err; + + inst = kzalloc(sizeof(*inst) + sizeof(*ctx), GFP_KERNEL); + if (!inst) + return -ENOMEM; + + ctx = aead_instance_ctx(inst); + err = crypto_grab_aead(&ctx->aead, aead_crypto_instance(inst), + crypto_attr_alg_name(tb[1]), 0, mask); + if (err) + goto err_free_inst; + + alg = crypto_spawn_aead_alg(&ctx->aead); + + err = -EINVAL; + + /* Underlying IV size must be 12. */ + if (crypto_aead_alg_ivsize(alg) != GCM_AES_IV_SIZE) + goto err_free_inst; + + /* Not a stream cipher? */ + if (alg->base.cra_blocksize != 1) + goto err_free_inst; + + err = -ENAMETOOLONG; + if (snprintf(inst->alg.base.cra_name, CRYPTO_MAX_ALG_NAME, + "rfc4543(%s)", alg->base.cra_name) >= + CRYPTO_MAX_ALG_NAME || + snprintf(inst->alg.base.cra_driver_name, CRYPTO_MAX_ALG_NAME, + "rfc4543(%s)", alg->base.cra_driver_name) >= + CRYPTO_MAX_ALG_NAME) + goto err_free_inst; + + 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.base.cra_ctxsize = sizeof(struct crypto_rfc4543_ctx); + + inst->alg.ivsize = GCM_RFC4543_IV_SIZE; + inst->alg.chunksize = crypto_aead_alg_chunksize(alg); + inst->alg.maxauthsize = crypto_aead_alg_maxauthsize(alg); + + inst->alg.init = crypto_rfc4543_init_tfm; + inst->alg.exit = crypto_rfc4543_exit_tfm; + + inst->alg.setkey = crypto_rfc4543_setkey; + inst->alg.setauthsize = crypto_rfc4543_setauthsize; + inst->alg.encrypt = crypto_rfc4543_encrypt; + inst->alg.decrypt = crypto_rfc4543_decrypt; + + inst->free = crypto_rfc4543_free; + + err = aead_register_instance(tmpl, inst); + if (err) { +err_free_inst: + crypto_rfc4543_free(inst); + } + return err; +} + +static struct crypto_template crypto_gcm_tmpls[] = { + { + .name = "gcm_base", + .create = crypto_gcm_base_create, + .module = THIS_MODULE, + }, { + .name = "gcm", + .create = crypto_gcm_create, + .module = THIS_MODULE, + }, { + .name = "rfc4106", + .create = crypto_rfc4106_create, + .module = THIS_MODULE, + }, { + .name = "rfc4543", + .create = crypto_rfc4543_create, + .module = THIS_MODULE, + }, +}; + +static int __init crypto_gcm_module_init(void) +{ + return crypto_register_templates(crypto_gcm_tmpls, + ARRAY_SIZE(crypto_gcm_tmpls)); +} + +static void __exit crypto_gcm_module_exit(void) +{ + crypto_unregister_templates(crypto_gcm_tmpls, + ARRAY_SIZE(crypto_gcm_tmpls)); +} + +module_init(crypto_gcm_module_init); +module_exit(crypto_gcm_module_exit); + +MODULE_LICENSE("GPL"); +MODULE_DESCRIPTION("Galois/Counter Mode"); +MODULE_AUTHOR("Mikko Herranen <mh1@iki.fi>"); +MODULE_ALIAS_CRYPTO("gcm_base"); +MODULE_ALIAS_CRYPTO("rfc4106"); +MODULE_ALIAS_CRYPTO("rfc4543"); +MODULE_ALIAS_CRYPTO("gcm"); |
