diff options
author | Paul Mackerras <paulus@samba.org> | 2008-01-31 01:25:51 +0100 |
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committer | Paul Mackerras <paulus@samba.org> | 2008-01-31 01:25:51 +0100 |
commit | bd45ac0c5daae35e7c71138172e63df5cf644cf6 (patch) | |
tree | 5eb5a599bf6a9d7a8a34e802db932aa9e9555de4 /crypto/gcm.c | |
parent | Merge branch 'for-2.6.25' of git://git.secretlab.ca/git/linux-2.6-mpc52xx (diff) | |
parent | Merge git://git.kernel.org/pub/scm/linux/kernel/git/wim/linux-2.6-watchdog (diff) | |
download | linux-bd45ac0c5daae35e7c71138172e63df5cf644cf6.tar.xz linux-bd45ac0c5daae35e7c71138172e63df5cf644cf6.zip |
Merge branch 'linux-2.6'
Diffstat (limited to 'crypto/gcm.c')
-rw-r--r-- | crypto/gcm.c | 823 |
1 files changed, 823 insertions, 0 deletions
diff --git a/crypto/gcm.c b/crypto/gcm.c new file mode 100644 index 000000000000..e70afd0c73dd --- /dev/null +++ b/crypto/gcm.c @@ -0,0 +1,823 @@ +/* + * GCM: Galois/Counter Mode. + * + * Copyright (c) 2007 Nokia Siemens Networks - Mikko Herranen <mh1@iki.fi> + * + * This program is free software; you can redistribute it and/or modify it + * under the terms of the GNU General Public License version 2 as published + * by the Free Software Foundation. + */ + +#include <crypto/gf128mul.h> +#include <crypto/internal/aead.h> +#include <crypto/internal/skcipher.h> +#include <crypto/scatterwalk.h> +#include <linux/completion.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_ablkcipher *ctr; + struct gf128mul_4k *gf128; +}; + +struct crypto_rfc4106_ctx { + struct crypto_aead *child; + u8 nonce[4]; +}; + +struct crypto_gcm_ghash_ctx { + u32 bytes; + u32 flags; + struct gf128mul_4k *gf128; + u8 buffer[16]; +}; + +struct crypto_gcm_req_priv_ctx { + u8 auth_tag[16]; + u8 iauth_tag[16]; + struct scatterlist src[2]; + struct scatterlist dst[2]; + struct crypto_gcm_ghash_ctx ghash; + struct ablkcipher_request abreq; +}; + +struct crypto_gcm_setkey_result { + int err; + struct completion completion; +}; + +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 void crypto_gcm_ghash_init(struct crypto_gcm_ghash_ctx *ctx, u32 flags, + struct gf128mul_4k *gf128) +{ + ctx->bytes = 0; + ctx->flags = flags; + ctx->gf128 = gf128; + memset(ctx->buffer, 0, 16); +} + +static void crypto_gcm_ghash_update(struct crypto_gcm_ghash_ctx *ctx, + const u8 *src, unsigned int srclen) +{ + u8 *dst = ctx->buffer; + + if (ctx->bytes) { + int n = min(srclen, ctx->bytes); + u8 *pos = dst + (16 - ctx->bytes); + + ctx->bytes -= n; + srclen -= n; + + while (n--) + *pos++ ^= *src++; + + if (!ctx->bytes) + gf128mul_4k_lle((be128 *)dst, ctx->gf128); + } + + while (srclen >= 16) { + crypto_xor(dst, src, 16); + gf128mul_4k_lle((be128 *)dst, ctx->gf128); + src += 16; + srclen -= 16; + } + + if (srclen) { + ctx->bytes = 16 - srclen; + while (srclen--) + *dst++ ^= *src++; + } +} + +static void crypto_gcm_ghash_update_sg(struct crypto_gcm_ghash_ctx *ctx, + struct scatterlist *sg, int len) +{ + struct scatter_walk walk; + u8 *src; + int n; + + if (!len) + return; + + scatterwalk_start(&walk, sg); + + while (len) { + n = scatterwalk_clamp(&walk, len); + + if (!n) { + scatterwalk_start(&walk, scatterwalk_sg_next(walk.sg)); + n = scatterwalk_clamp(&walk, len); + } + + src = scatterwalk_map(&walk, 0); + + crypto_gcm_ghash_update(ctx, src, n); + len -= n; + + scatterwalk_unmap(src, 0); + scatterwalk_advance(&walk, n); + scatterwalk_done(&walk, 0, len); + if (len) + crypto_yield(ctx->flags); + } +} + +static void crypto_gcm_ghash_flush(struct crypto_gcm_ghash_ctx *ctx) +{ + u8 *dst = ctx->buffer; + + if (ctx->bytes) { + u8 *tmp = dst + (16 - ctx->bytes); + + while (ctx->bytes--) + *tmp++ ^= 0; + + gf128mul_4k_lle((be128 *)dst, ctx->gf128); + } + + ctx->bytes = 0; +} + +static void crypto_gcm_ghash_final_xor(struct crypto_gcm_ghash_ctx *ctx, + unsigned int authlen, + unsigned int cryptlen, u8 *dst) +{ + u8 *buf = ctx->buffer; + u128 lengths; + + lengths.a = cpu_to_be64(authlen * 8); + lengths.b = cpu_to_be64(cryptlen * 8); + + crypto_gcm_ghash_flush(ctx); + crypto_xor(buf, (u8 *)&lengths, 16); + gf128mul_4k_lle((be128 *)buf, ctx->gf128); + crypto_xor(dst, buf, 16); +} + +static void crypto_gcm_setkey_done(struct crypto_async_request *req, int err) +{ + struct crypto_gcm_setkey_result *result = req->data; + + if (err == -EINPROGRESS) + return; + + result->err = err; + complete(&result->completion); +} + +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_ablkcipher *ctr = ctx->ctr; + struct { + be128 hash; + u8 iv[8]; + + struct crypto_gcm_setkey_result result; + + struct scatterlist sg[1]; + struct ablkcipher_request req; + } *data; + int err; + + 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); + if (err) + return err; + + crypto_aead_set_flags(aead, crypto_ablkcipher_get_flags(ctr) & + CRYPTO_TFM_RES_MASK); + + data = kzalloc(sizeof(*data) + crypto_ablkcipher_reqsize(ctr), + GFP_KERNEL); + if (!data) + return -ENOMEM; + + init_completion(&data->result.completion); + sg_init_one(data->sg, &data->hash, sizeof(data->hash)); + ablkcipher_request_set_tfm(&data->req, ctr); + ablkcipher_request_set_callback(&data->req, CRYPTO_TFM_REQ_MAY_SLEEP | + CRYPTO_TFM_REQ_MAY_BACKLOG, + crypto_gcm_setkey_done, + &data->result); + ablkcipher_request_set_crypt(&data->req, data->sg, data->sg, + sizeof(data->hash), data->iv); + + err = crypto_ablkcipher_encrypt(&data->req); + if (err == -EINPROGRESS || err == -EBUSY) { + err = wait_for_completion_interruptible( + &data->result.completion); + if (!err) + err = data->result.err; + } + + if (err) + goto out; + + if (ctx->gf128 != NULL) + gf128mul_free_4k(ctx->gf128); + + ctx->gf128 = gf128mul_init_4k_lle(&data->hash); + + if (ctx->gf128 == NULL) + err = -ENOMEM; + +out: + kfree(data); + return err; +} + +static int crypto_gcm_setauthsize(struct crypto_aead *tfm, + unsigned int authsize) +{ + switch (authsize) { + case 4: + case 8: + case 12: + case 13: + case 14: + case 15: + case 16: + break; + default: + return -EINVAL; + } + + return 0; +} + +static void crypto_gcm_init_crypt(struct ablkcipher_request *ablk_req, + 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); + u32 flags = req->base.tfm->crt_flags; + struct crypto_gcm_ghash_ctx *ghash = &pctx->ghash; + struct scatterlist *dst; + __be32 counter = cpu_to_be32(1); + + memset(pctx->auth_tag, 0, sizeof(pctx->auth_tag)); + memcpy(req->iv + 12, &counter, 4); + + sg_init_table(pctx->src, 2); + sg_set_buf(pctx->src, pctx->auth_tag, sizeof(pctx->auth_tag)); + 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, pctx->auth_tag, sizeof(pctx->auth_tag)); + scatterwalk_sg_chain(pctx->dst, 2, req->dst); + dst = pctx->dst; + } + + ablkcipher_request_set_tfm(ablk_req, ctx->ctr); + ablkcipher_request_set_crypt(ablk_req, pctx->src, dst, + cryptlen + sizeof(pctx->auth_tag), + req->iv); + + crypto_gcm_ghash_init(ghash, flags, ctx->gf128); + + crypto_gcm_ghash_update_sg(ghash, req->assoc, req->assoclen); + crypto_gcm_ghash_flush(ghash); +} + +static int crypto_gcm_hash(struct aead_request *req) +{ + struct crypto_aead *aead = crypto_aead_reqtfm(req); + struct crypto_gcm_req_priv_ctx *pctx = crypto_gcm_reqctx(req); + u8 *auth_tag = pctx->auth_tag; + struct crypto_gcm_ghash_ctx *ghash = &pctx->ghash; + + crypto_gcm_ghash_update_sg(ghash, req->dst, req->cryptlen); + crypto_gcm_ghash_final_xor(ghash, req->assoclen, req->cryptlen, + auth_tag); + + scatterwalk_map_and_copy(auth_tag, req->dst, req->cryptlen, + crypto_aead_authsize(aead), 1); + return 0; +} + +static void crypto_gcm_encrypt_done(struct crypto_async_request *areq, int err) +{ + struct aead_request *req = areq->data; + + if (!err) + err = crypto_gcm_hash(req); + + 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 ablkcipher_request *abreq = &pctx->abreq; + int err; + + crypto_gcm_init_crypt(abreq, req, req->cryptlen); + ablkcipher_request_set_callback(abreq, aead_request_flags(req), + crypto_gcm_encrypt_done, req); + + err = crypto_ablkcipher_encrypt(abreq); + if (err) + return err; + + return crypto_gcm_hash(req); +} + +static int crypto_gcm_verify(struct aead_request *req) +{ + struct crypto_aead *aead = crypto_aead_reqtfm(req); + struct crypto_gcm_req_priv_ctx *pctx = crypto_gcm_reqctx(req); + struct crypto_gcm_ghash_ctx *ghash = &pctx->ghash; + 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_gcm_ghash_final_xor(ghash, req->assoclen, cryptlen, auth_tag); + + authsize = crypto_aead_authsize(aead); + scatterwalk_map_and_copy(iauth_tag, req->src, cryptlen, authsize, 0); + return memcmp(iauth_tag, auth_tag, authsize) ? -EBADMSG : 0; +} + +static void crypto_gcm_decrypt_done(struct crypto_async_request *areq, int err) +{ + struct aead_request *req = areq->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 ablkcipher_request *abreq = &pctx->abreq; + struct crypto_gcm_ghash_ctx *ghash = &pctx->ghash; + unsigned int cryptlen = req->cryptlen; + unsigned int authsize = crypto_aead_authsize(aead); + int err; + + if (cryptlen < authsize) + return -EINVAL; + cryptlen -= authsize; + + crypto_gcm_init_crypt(abreq, req, cryptlen); + ablkcipher_request_set_callback(abreq, aead_request_flags(req), + crypto_gcm_decrypt_done, req); + + crypto_gcm_ghash_update_sg(ghash, req->src, cryptlen); + + err = crypto_ablkcipher_decrypt(abreq); + if (err) + return err; + + return crypto_gcm_verify(req); +} + +static int crypto_gcm_init_tfm(struct crypto_tfm *tfm) +{ + struct crypto_instance *inst = (void *)tfm->__crt_alg; + struct gcm_instance_ctx *ictx = crypto_instance_ctx(inst); + struct crypto_gcm_ctx *ctx = crypto_tfm_ctx(tfm); + struct crypto_ablkcipher *ctr; + unsigned long align; + int err; + + ctr = crypto_spawn_skcipher(&ictx->ctr); + err = PTR_ERR(ctr); + if (IS_ERR(ctr)) + return err; + + ctx->ctr = ctr; + ctx->gf128 = NULL; + + align = crypto_tfm_alg_alignmask(tfm); + align &= ~(crypto_tfm_ctx_alignment() - 1); + tfm->crt_aead.reqsize = align + + sizeof(struct crypto_gcm_req_priv_ctx) + + crypto_ablkcipher_reqsize(ctr); + + return 0; +} + +static void crypto_gcm_exit_tfm(struct crypto_tfm *tfm) +{ + struct crypto_gcm_ctx *ctx = crypto_tfm_ctx(tfm); + + if (ctx->gf128 != NULL) + gf128mul_free_4k(ctx->gf128); + + crypto_free_ablkcipher(ctx->ctr); +} + +static struct crypto_instance *crypto_gcm_alloc_common(struct rtattr **tb, + const char *full_name, + const char *ctr_name) +{ + struct crypto_attr_type *algt; + struct crypto_instance *inst; + struct crypto_alg *ctr; + struct gcm_instance_ctx *ctx; + int err; + + algt = crypto_get_attr_type(tb); + err = PTR_ERR(algt); + if (IS_ERR(algt)) + return ERR_PTR(err); + + if ((algt->type ^ CRYPTO_ALG_TYPE_AEAD) & algt->mask) + return ERR_PTR(-EINVAL); + + inst = kzalloc(sizeof(*inst) + sizeof(*ctx), GFP_KERNEL); + if (!inst) + return ERR_PTR(-ENOMEM); + + ctx = crypto_instance_ctx(inst); + crypto_set_skcipher_spawn(&ctx->ctr, inst); + err = crypto_grab_skcipher(&ctx->ctr, ctr_name, 0, + crypto_requires_sync(algt->type, + algt->mask)); + if (err) + goto err_free_inst; + + ctr = crypto_skcipher_spawn_alg(&ctx->ctr); + + /* We only support 16-byte blocks. */ + if (ctr->cra_ablkcipher.ivsize != 16) + goto out_put_ctr; + + /* Not a stream cipher? */ + err = -EINVAL; + if (ctr->cra_blocksize != 1) + goto out_put_ctr; + + err = -ENAMETOOLONG; + if (snprintf(inst->alg.cra_driver_name, CRYPTO_MAX_ALG_NAME, + "gcm_base(%s)", ctr->cra_driver_name) >= + CRYPTO_MAX_ALG_NAME) + goto out_put_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 = ctr->cra_priority; + inst->alg.cra_blocksize = 1; + inst->alg.cra_alignmask = ctr->cra_alignmask | (__alignof__(u64) - 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_gcm_ctx); + inst->alg.cra_init = crypto_gcm_init_tfm; + inst->alg.cra_exit = crypto_gcm_exit_tfm; + inst->alg.cra_aead.setkey = crypto_gcm_setkey; + inst->alg.cra_aead.setauthsize = crypto_gcm_setauthsize; + inst->alg.cra_aead.encrypt = crypto_gcm_encrypt; + inst->alg.cra_aead.decrypt = crypto_gcm_decrypt; + +out: + return inst; + +out_put_ctr: + crypto_drop_skcipher(&ctx->ctr); +err_free_inst: + kfree(inst); + inst = ERR_PTR(err); + goto out; +} + +static struct crypto_instance *crypto_gcm_alloc(struct rtattr **tb) +{ + int err; + 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]); + err = PTR_ERR(cipher_name); + if (IS_ERR(cipher_name)) + return ERR_PTR(err); + + 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, "gcm(%s)", cipher_name) >= + CRYPTO_MAX_ALG_NAME) + return ERR_PTR(-ENAMETOOLONG); + + return crypto_gcm_alloc_common(tb, full_name, ctr_name); +} + +static void crypto_gcm_free(struct crypto_instance *inst) +{ + struct gcm_instance_ctx *ctx = crypto_instance_ctx(inst); + + crypto_drop_skcipher(&ctx->ctr); + kfree(inst); +} + +static struct crypto_template crypto_gcm_tmpl = { + .name = "gcm", + .alloc = crypto_gcm_alloc, + .free = crypto_gcm_free, + .module = THIS_MODULE, +}; + +static struct crypto_instance *crypto_gcm_base_alloc(struct rtattr **tb) +{ + int err; + const char *ctr_name; + char full_name[CRYPTO_MAX_ALG_NAME]; + + ctr_name = crypto_attr_alg_name(tb[1]); + err = PTR_ERR(ctr_name); + if (IS_ERR(ctr_name)) + return ERR_PTR(err); + + if (snprintf(full_name, CRYPTO_MAX_ALG_NAME, "gcm_base(%s)", + ctr_name) >= CRYPTO_MAX_ALG_NAME) + return ERR_PTR(-ENAMETOOLONG); + + return crypto_gcm_alloc_common(tb, full_name, ctr_name); +} + +static struct crypto_template crypto_gcm_base_tmpl = { + .name = "gcm_base", + .alloc = crypto_gcm_base_alloc, + .free = crypto_gcm_free, + .module = THIS_MODULE, +}; + +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; + int err; + + 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); + 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_rfc4106_setauthsize(struct crypto_aead *parent, + unsigned int authsize) +{ + struct crypto_rfc4106_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_rfc4106_crypt(struct aead_request *req) +{ + struct aead_request *subreq = aead_request_ctx(req); + struct crypto_aead *aead = crypto_aead_reqtfm(req); + struct crypto_rfc4106_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); + + memcpy(iv, ctx->nonce, 4); + 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_rfc4106_encrypt(struct aead_request *req) +{ + req = crypto_rfc4106_crypt(req); + + return crypto_aead_encrypt(req); +} + +static int crypto_rfc4106_decrypt(struct aead_request *req) +{ + req = crypto_rfc4106_crypt(req); + + return crypto_aead_decrypt(req); +} + +static int crypto_rfc4106_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_rfc4106_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_rfc4106_exit_tfm(struct crypto_tfm *tfm) +{ + struct crypto_rfc4106_ctx *ctx = crypto_tfm_ctx(tfm); + + crypto_free_aead(ctx->child); +} + +static struct crypto_instance *crypto_rfc4106_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); + err = PTR_ERR(algt); + if (IS_ERR(algt)) + return ERR_PTR(err); + + if ((algt->type ^ CRYPTO_ALG_TYPE_AEAD) & algt->mask) + return ERR_PTR(-EINVAL); + + ccm_name = crypto_attr_alg_name(tb[1]); + err = PTR_ERR(ccm_name); + if (IS_ERR(ccm_name)) + return ERR_PTR(err); + + 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, + "rfc4106(%s)", alg->cra_name) >= CRYPTO_MAX_ALG_NAME || + snprintf(inst->alg.cra_driver_name, CRYPTO_MAX_ALG_NAME, + "rfc4106(%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_rfc4106_ctx); + + inst->alg.cra_init = crypto_rfc4106_init_tfm; + inst->alg.cra_exit = crypto_rfc4106_exit_tfm; + + inst->alg.cra_aead.setkey = crypto_rfc4106_setkey; + inst->alg.cra_aead.setauthsize = crypto_rfc4106_setauthsize; + inst->alg.cra_aead.encrypt = crypto_rfc4106_encrypt; + inst->alg.cra_aead.decrypt = crypto_rfc4106_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_rfc4106_free(struct crypto_instance *inst) +{ + crypto_drop_spawn(crypto_instance_ctx(inst)); + kfree(inst); +} + +static struct crypto_template crypto_rfc4106_tmpl = { + .name = "rfc4106", + .alloc = crypto_rfc4106_alloc, + .free = crypto_rfc4106_free, + .module = THIS_MODULE, +}; + +static int __init crypto_gcm_module_init(void) +{ + int err; + + err = crypto_register_template(&crypto_gcm_base_tmpl); + if (err) + goto out; + + err = crypto_register_template(&crypto_gcm_tmpl); + if (err) + goto out_undo_base; + + err = crypto_register_template(&crypto_rfc4106_tmpl); + if (err) + goto out_undo_gcm; + +out: + return err; + +out_undo_gcm: + crypto_unregister_template(&crypto_gcm_tmpl); +out_undo_base: + crypto_unregister_template(&crypto_gcm_base_tmpl); + goto out; +} + +static void __exit crypto_gcm_module_exit(void) +{ + crypto_unregister_template(&crypto_rfc4106_tmpl); + crypto_unregister_template(&crypto_gcm_tmpl); + crypto_unregister_template(&crypto_gcm_base_tmpl); +} + +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("gcm_base"); +MODULE_ALIAS("rfc4106"); |