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authorAndré Fabian Silva Delgado <emulatorman@parabola.nu>2015-08-05 17:04:01 -0300
committerAndré Fabian Silva Delgado <emulatorman@parabola.nu>2015-08-05 17:04:01 -0300
commit57f0f512b273f60d52568b8c6b77e17f5636edc0 (patch)
tree5e910f0e82173f4ef4f51111366a3f1299037a7b /crypto/ablkcipher.c
Initial import
Diffstat (limited to 'crypto/ablkcipher.c')
-rw-r--r--crypto/ablkcipher.c709
1 files changed, 709 insertions, 0 deletions
diff --git a/crypto/ablkcipher.c b/crypto/ablkcipher.c
new file mode 100644
index 000000000..db201bca1
--- /dev/null
+++ b/crypto/ablkcipher.c
@@ -0,0 +1,709 @@
+/*
+ * Asynchronous block chaining cipher operations.
+ *
+ * This is the asynchronous version of blkcipher.c indicating completion
+ * via a callback.
+ *
+ * Copyright (c) 2006 Herbert Xu <herbert@gondor.apana.org.au>
+ *
+ * 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/skcipher.h>
+#include <linux/cpumask.h>
+#include <linux/err.h>
+#include <linux/kernel.h>
+#include <linux/rtnetlink.h>
+#include <linux/sched.h>
+#include <linux/slab.h>
+#include <linux/seq_file.h>
+#include <linux/cryptouser.h>
+#include <net/netlink.h>
+
+#include <crypto/scatterwalk.h>
+
+#include "internal.h"
+
+struct ablkcipher_buffer {
+ struct list_head entry;
+ struct scatter_walk dst;
+ unsigned int len;
+ void *data;
+};
+
+enum {
+ ABLKCIPHER_WALK_SLOW = 1 << 0,
+};
+
+static inline void ablkcipher_buffer_write(struct ablkcipher_buffer *p)
+{
+ scatterwalk_copychunks(p->data, &p->dst, p->len, 1);
+}
+
+void __ablkcipher_walk_complete(struct ablkcipher_walk *walk)
+{
+ struct ablkcipher_buffer *p, *tmp;
+
+ list_for_each_entry_safe(p, tmp, &walk->buffers, entry) {
+ ablkcipher_buffer_write(p);
+ list_del(&p->entry);
+ kfree(p);
+ }
+}
+EXPORT_SYMBOL_GPL(__ablkcipher_walk_complete);
+
+static inline void ablkcipher_queue_write(struct ablkcipher_walk *walk,
+ struct ablkcipher_buffer *p)
+{
+ p->dst = walk->out;
+ list_add_tail(&p->entry, &walk->buffers);
+}
+
+/* Get a spot of the specified length that does not straddle a page.
+ * The caller needs to ensure that there is enough space for this operation.
+ */
+static inline u8 *ablkcipher_get_spot(u8 *start, unsigned int len)
+{
+ u8 *end_page = (u8 *)(((unsigned long)(start + len - 1)) & PAGE_MASK);
+
+ return max(start, end_page);
+}
+
+static inline unsigned int ablkcipher_done_slow(struct ablkcipher_walk *walk,
+ unsigned int bsize)
+{
+ unsigned int n = bsize;
+
+ for (;;) {
+ unsigned int len_this_page = scatterwalk_pagelen(&walk->out);
+
+ if (len_this_page > n)
+ len_this_page = n;
+ scatterwalk_advance(&walk->out, n);
+ if (n == len_this_page)
+ break;
+ n -= len_this_page;
+ scatterwalk_start(&walk->out, sg_next(walk->out.sg));
+ }
+
+ return bsize;
+}
+
+static inline unsigned int ablkcipher_done_fast(struct ablkcipher_walk *walk,
+ unsigned int n)
+{
+ scatterwalk_advance(&walk->in, n);
+ scatterwalk_advance(&walk->out, n);
+
+ return n;
+}
+
+static int ablkcipher_walk_next(struct ablkcipher_request *req,
+ struct ablkcipher_walk *walk);
+
+int ablkcipher_walk_done(struct ablkcipher_request *req,
+ struct ablkcipher_walk *walk, int err)
+{
+ struct crypto_tfm *tfm = req->base.tfm;
+ unsigned int nbytes = 0;
+
+ if (likely(err >= 0)) {
+ unsigned int n = walk->nbytes - err;
+
+ if (likely(!(walk->flags & ABLKCIPHER_WALK_SLOW)))
+ n = ablkcipher_done_fast(walk, n);
+ else if (WARN_ON(err)) {
+ err = -EINVAL;
+ goto err;
+ } else
+ n = ablkcipher_done_slow(walk, n);
+
+ nbytes = walk->total - n;
+ err = 0;
+ }
+
+ scatterwalk_done(&walk->in, 0, nbytes);
+ scatterwalk_done(&walk->out, 1, nbytes);
+
+err:
+ walk->total = nbytes;
+ walk->nbytes = nbytes;
+
+ if (nbytes) {
+ crypto_yield(req->base.flags);
+ return ablkcipher_walk_next(req, walk);
+ }
+
+ if (walk->iv != req->info)
+ memcpy(req->info, walk->iv, tfm->crt_ablkcipher.ivsize);
+ kfree(walk->iv_buffer);
+
+ return err;
+}
+EXPORT_SYMBOL_GPL(ablkcipher_walk_done);
+
+static inline int ablkcipher_next_slow(struct ablkcipher_request *req,
+ struct ablkcipher_walk *walk,
+ unsigned int bsize,
+ unsigned int alignmask,
+ void **src_p, void **dst_p)
+{
+ unsigned aligned_bsize = ALIGN(bsize, alignmask + 1);
+ struct ablkcipher_buffer *p;
+ void *src, *dst, *base;
+ unsigned int n;
+
+ n = ALIGN(sizeof(struct ablkcipher_buffer), alignmask + 1);
+ n += (aligned_bsize * 3 - (alignmask + 1) +
+ (alignmask & ~(crypto_tfm_ctx_alignment() - 1)));
+
+ p = kmalloc(n, GFP_ATOMIC);
+ if (!p)
+ return ablkcipher_walk_done(req, walk, -ENOMEM);
+
+ base = p + 1;
+
+ dst = (u8 *)ALIGN((unsigned long)base, alignmask + 1);
+ src = dst = ablkcipher_get_spot(dst, bsize);
+
+ p->len = bsize;
+ p->data = dst;
+
+ scatterwalk_copychunks(src, &walk->in, bsize, 0);
+
+ ablkcipher_queue_write(walk, p);
+
+ walk->nbytes = bsize;
+ walk->flags |= ABLKCIPHER_WALK_SLOW;
+
+ *src_p = src;
+ *dst_p = dst;
+
+ return 0;
+}
+
+static inline int ablkcipher_copy_iv(struct ablkcipher_walk *walk,
+ struct crypto_tfm *tfm,
+ unsigned int alignmask)
+{
+ unsigned bs = walk->blocksize;
+ unsigned int ivsize = tfm->crt_ablkcipher.ivsize;
+ unsigned aligned_bs = ALIGN(bs, alignmask + 1);
+ unsigned int size = aligned_bs * 2 + ivsize + max(aligned_bs, ivsize) -
+ (alignmask + 1);
+ u8 *iv;
+
+ size += alignmask & ~(crypto_tfm_ctx_alignment() - 1);
+ walk->iv_buffer = kmalloc(size, GFP_ATOMIC);
+ if (!walk->iv_buffer)
+ return -ENOMEM;
+
+ iv = (u8 *)ALIGN((unsigned long)walk->iv_buffer, alignmask + 1);
+ iv = ablkcipher_get_spot(iv, bs) + aligned_bs;
+ iv = ablkcipher_get_spot(iv, bs) + aligned_bs;
+ iv = ablkcipher_get_spot(iv, ivsize);
+
+ walk->iv = memcpy(iv, walk->iv, ivsize);
+ return 0;
+}
+
+static inline int ablkcipher_next_fast(struct ablkcipher_request *req,
+ struct ablkcipher_walk *walk)
+{
+ walk->src.page = scatterwalk_page(&walk->in);
+ walk->src.offset = offset_in_page(walk->in.offset);
+ walk->dst.page = scatterwalk_page(&walk->out);
+ walk->dst.offset = offset_in_page(walk->out.offset);
+
+ return 0;
+}
+
+static int ablkcipher_walk_next(struct ablkcipher_request *req,
+ struct ablkcipher_walk *walk)
+{
+ struct crypto_tfm *tfm = req->base.tfm;
+ unsigned int alignmask, bsize, n;
+ void *src, *dst;
+ int err;
+
+ alignmask = crypto_tfm_alg_alignmask(tfm);
+ n = walk->total;
+ if (unlikely(n < crypto_tfm_alg_blocksize(tfm))) {
+ req->base.flags |= CRYPTO_TFM_RES_BAD_BLOCK_LEN;
+ return ablkcipher_walk_done(req, walk, -EINVAL);
+ }
+
+ walk->flags &= ~ABLKCIPHER_WALK_SLOW;
+ src = dst = NULL;
+
+ bsize = min(walk->blocksize, n);
+ n = scatterwalk_clamp(&walk->in, n);
+ n = scatterwalk_clamp(&walk->out, n);
+
+ if (n < bsize ||
+ !scatterwalk_aligned(&walk->in, alignmask) ||
+ !scatterwalk_aligned(&walk->out, alignmask)) {
+ err = ablkcipher_next_slow(req, walk, bsize, alignmask,
+ &src, &dst);
+ goto set_phys_lowmem;
+ }
+
+ walk->nbytes = n;
+
+ return ablkcipher_next_fast(req, walk);
+
+set_phys_lowmem:
+ if (err >= 0) {
+ walk->src.page = virt_to_page(src);
+ walk->dst.page = virt_to_page(dst);
+ walk->src.offset = ((unsigned long)src & (PAGE_SIZE - 1));
+ walk->dst.offset = ((unsigned long)dst & (PAGE_SIZE - 1));
+ }
+
+ return err;
+}
+
+static int ablkcipher_walk_first(struct ablkcipher_request *req,
+ struct ablkcipher_walk *walk)
+{
+ struct crypto_tfm *tfm = req->base.tfm;
+ unsigned int alignmask;
+
+ alignmask = crypto_tfm_alg_alignmask(tfm);
+ if (WARN_ON_ONCE(in_irq()))
+ return -EDEADLK;
+
+ walk->nbytes = walk->total;
+ if (unlikely(!walk->total))
+ return 0;
+
+ walk->iv_buffer = NULL;
+ walk->iv = req->info;
+ if (unlikely(((unsigned long)walk->iv & alignmask))) {
+ int err = ablkcipher_copy_iv(walk, tfm, alignmask);
+
+ if (err)
+ return err;
+ }
+
+ scatterwalk_start(&walk->in, walk->in.sg);
+ scatterwalk_start(&walk->out, walk->out.sg);
+
+ return ablkcipher_walk_next(req, walk);
+}
+
+int ablkcipher_walk_phys(struct ablkcipher_request *req,
+ struct ablkcipher_walk *walk)
+{
+ walk->blocksize = crypto_tfm_alg_blocksize(req->base.tfm);
+ return ablkcipher_walk_first(req, walk);
+}
+EXPORT_SYMBOL_GPL(ablkcipher_walk_phys);
+
+static int setkey_unaligned(struct crypto_ablkcipher *tfm, const u8 *key,
+ unsigned int keylen)
+{
+ struct ablkcipher_alg *cipher = crypto_ablkcipher_alg(tfm);
+ unsigned long alignmask = crypto_ablkcipher_alignmask(tfm);
+ int ret;
+ u8 *buffer, *alignbuffer;
+ unsigned long absize;
+
+ absize = keylen + alignmask;
+ buffer = kmalloc(absize, GFP_ATOMIC);
+ if (!buffer)
+ return -ENOMEM;
+
+ alignbuffer = (u8 *)ALIGN((unsigned long)buffer, alignmask + 1);
+ memcpy(alignbuffer, key, keylen);
+ ret = cipher->setkey(tfm, alignbuffer, keylen);
+ memset(alignbuffer, 0, keylen);
+ kfree(buffer);
+ return ret;
+}
+
+static int setkey(struct crypto_ablkcipher *tfm, const u8 *key,
+ unsigned int keylen)
+{
+ struct ablkcipher_alg *cipher = crypto_ablkcipher_alg(tfm);
+ unsigned long alignmask = crypto_ablkcipher_alignmask(tfm);
+
+ if (keylen < cipher->min_keysize || keylen > cipher->max_keysize) {
+ crypto_ablkcipher_set_flags(tfm, CRYPTO_TFM_RES_BAD_KEY_LEN);
+ return -EINVAL;
+ }
+
+ if ((unsigned long)key & alignmask)
+ return setkey_unaligned(tfm, key, keylen);
+
+ return cipher->setkey(tfm, key, keylen);
+}
+
+static unsigned int crypto_ablkcipher_ctxsize(struct crypto_alg *alg, u32 type,
+ u32 mask)
+{
+ return alg->cra_ctxsize;
+}
+
+int skcipher_null_givencrypt(struct skcipher_givcrypt_request *req)
+{
+ return crypto_ablkcipher_encrypt(&req->creq);
+}
+
+int skcipher_null_givdecrypt(struct skcipher_givcrypt_request *req)
+{
+ return crypto_ablkcipher_decrypt(&req->creq);
+}
+
+static int crypto_init_ablkcipher_ops(struct crypto_tfm *tfm, u32 type,
+ u32 mask)
+{
+ struct ablkcipher_alg *alg = &tfm->__crt_alg->cra_ablkcipher;
+ struct ablkcipher_tfm *crt = &tfm->crt_ablkcipher;
+
+ if (alg->ivsize > PAGE_SIZE / 8)
+ return -EINVAL;
+
+ crt->setkey = setkey;
+ crt->encrypt = alg->encrypt;
+ crt->decrypt = alg->decrypt;
+ if (!alg->ivsize) {
+ crt->givencrypt = skcipher_null_givencrypt;
+ crt->givdecrypt = skcipher_null_givdecrypt;
+ }
+ crt->base = __crypto_ablkcipher_cast(tfm);
+ crt->ivsize = alg->ivsize;
+
+ return 0;
+}
+
+#ifdef CONFIG_NET
+static int crypto_ablkcipher_report(struct sk_buff *skb, struct crypto_alg *alg)
+{
+ struct crypto_report_blkcipher rblkcipher;
+
+ strncpy(rblkcipher.type, "ablkcipher", sizeof(rblkcipher.type));
+ strncpy(rblkcipher.geniv, alg->cra_ablkcipher.geniv ?: "<default>",
+ sizeof(rblkcipher.geniv));
+
+ rblkcipher.blocksize = alg->cra_blocksize;
+ rblkcipher.min_keysize = alg->cra_ablkcipher.min_keysize;
+ rblkcipher.max_keysize = alg->cra_ablkcipher.max_keysize;
+ rblkcipher.ivsize = alg->cra_ablkcipher.ivsize;
+
+ if (nla_put(skb, CRYPTOCFGA_REPORT_BLKCIPHER,
+ sizeof(struct crypto_report_blkcipher), &rblkcipher))
+ goto nla_put_failure;
+ return 0;
+
+nla_put_failure:
+ return -EMSGSIZE;
+}
+#else
+static int crypto_ablkcipher_report(struct sk_buff *skb, struct crypto_alg *alg)
+{
+ return -ENOSYS;
+}
+#endif
+
+static void crypto_ablkcipher_show(struct seq_file *m, struct crypto_alg *alg)
+ __attribute__ ((unused));
+static void crypto_ablkcipher_show(struct seq_file *m, struct crypto_alg *alg)
+{
+ struct ablkcipher_alg *ablkcipher = &alg->cra_ablkcipher;
+
+ seq_printf(m, "type : ablkcipher\n");
+ seq_printf(m, "async : %s\n", alg->cra_flags & CRYPTO_ALG_ASYNC ?
+ "yes" : "no");
+ seq_printf(m, "blocksize : %u\n", alg->cra_blocksize);
+ seq_printf(m, "min keysize : %u\n", ablkcipher->min_keysize);
+ seq_printf(m, "max keysize : %u\n", ablkcipher->max_keysize);
+ seq_printf(m, "ivsize : %u\n", ablkcipher->ivsize);
+ seq_printf(m, "geniv : %s\n", ablkcipher->geniv ?: "<default>");
+}
+
+const struct crypto_type crypto_ablkcipher_type = {
+ .ctxsize = crypto_ablkcipher_ctxsize,
+ .init = crypto_init_ablkcipher_ops,
+#ifdef CONFIG_PROC_FS
+ .show = crypto_ablkcipher_show,
+#endif
+ .report = crypto_ablkcipher_report,
+};
+EXPORT_SYMBOL_GPL(crypto_ablkcipher_type);
+
+static int no_givdecrypt(struct skcipher_givcrypt_request *req)
+{
+ return -ENOSYS;
+}
+
+static int crypto_init_givcipher_ops(struct crypto_tfm *tfm, u32 type,
+ u32 mask)
+{
+ struct ablkcipher_alg *alg = &tfm->__crt_alg->cra_ablkcipher;
+ struct ablkcipher_tfm *crt = &tfm->crt_ablkcipher;
+
+ if (alg->ivsize > PAGE_SIZE / 8)
+ return -EINVAL;
+
+ crt->setkey = tfm->__crt_alg->cra_flags & CRYPTO_ALG_GENIV ?
+ alg->setkey : setkey;
+ crt->encrypt = alg->encrypt;
+ crt->decrypt = alg->decrypt;
+ crt->givencrypt = alg->givencrypt;
+ crt->givdecrypt = alg->givdecrypt ?: no_givdecrypt;
+ crt->base = __crypto_ablkcipher_cast(tfm);
+ crt->ivsize = alg->ivsize;
+
+ return 0;
+}
+
+#ifdef CONFIG_NET
+static int crypto_givcipher_report(struct sk_buff *skb, struct crypto_alg *alg)
+{
+ struct crypto_report_blkcipher rblkcipher;
+
+ strncpy(rblkcipher.type, "givcipher", sizeof(rblkcipher.type));
+ strncpy(rblkcipher.geniv, alg->cra_ablkcipher.geniv ?: "<built-in>",
+ sizeof(rblkcipher.geniv));
+
+ rblkcipher.blocksize = alg->cra_blocksize;
+ rblkcipher.min_keysize = alg->cra_ablkcipher.min_keysize;
+ rblkcipher.max_keysize = alg->cra_ablkcipher.max_keysize;
+ rblkcipher.ivsize = alg->cra_ablkcipher.ivsize;
+
+ if (nla_put(skb, CRYPTOCFGA_REPORT_BLKCIPHER,
+ sizeof(struct crypto_report_blkcipher), &rblkcipher))
+ goto nla_put_failure;
+ return 0;
+
+nla_put_failure:
+ return -EMSGSIZE;
+}
+#else
+static int crypto_givcipher_report(struct sk_buff *skb, struct crypto_alg *alg)
+{
+ return -ENOSYS;
+}
+#endif
+
+static void crypto_givcipher_show(struct seq_file *m, struct crypto_alg *alg)
+ __attribute__ ((unused));
+static void crypto_givcipher_show(struct seq_file *m, struct crypto_alg *alg)
+{
+ struct ablkcipher_alg *ablkcipher = &alg->cra_ablkcipher;
+
+ seq_printf(m, "type : givcipher\n");
+ seq_printf(m, "async : %s\n", alg->cra_flags & CRYPTO_ALG_ASYNC ?
+ "yes" : "no");
+ seq_printf(m, "blocksize : %u\n", alg->cra_blocksize);
+ seq_printf(m, "min keysize : %u\n", ablkcipher->min_keysize);
+ seq_printf(m, "max keysize : %u\n", ablkcipher->max_keysize);
+ seq_printf(m, "ivsize : %u\n", ablkcipher->ivsize);
+ seq_printf(m, "geniv : %s\n", ablkcipher->geniv ?: "<built-in>");
+}
+
+const struct crypto_type crypto_givcipher_type = {
+ .ctxsize = crypto_ablkcipher_ctxsize,
+ .init = crypto_init_givcipher_ops,
+#ifdef CONFIG_PROC_FS
+ .show = crypto_givcipher_show,
+#endif
+ .report = crypto_givcipher_report,
+};
+EXPORT_SYMBOL_GPL(crypto_givcipher_type);
+
+const char *crypto_default_geniv(const struct crypto_alg *alg)
+{
+ if (((alg->cra_flags & CRYPTO_ALG_TYPE_MASK) ==
+ CRYPTO_ALG_TYPE_BLKCIPHER ? alg->cra_blkcipher.ivsize :
+ alg->cra_ablkcipher.ivsize) !=
+ alg->cra_blocksize)
+ return "chainiv";
+
+ return "eseqiv";
+}
+
+static int crypto_givcipher_default(struct crypto_alg *alg, u32 type, u32 mask)
+{
+ struct rtattr *tb[3];
+ struct {
+ struct rtattr attr;
+ struct crypto_attr_type data;
+ } ptype;
+ struct {
+ struct rtattr attr;
+ struct crypto_attr_alg data;
+ } palg;
+ struct crypto_template *tmpl;
+ struct crypto_instance *inst;
+ struct crypto_alg *larval;
+ const char *geniv;
+ int err;
+
+ larval = crypto_larval_lookup(alg->cra_driver_name,
+ (type & ~CRYPTO_ALG_TYPE_MASK) |
+ CRYPTO_ALG_TYPE_GIVCIPHER,
+ mask | CRYPTO_ALG_TYPE_MASK);
+ err = PTR_ERR(larval);
+ if (IS_ERR(larval))
+ goto out;
+
+ err = -EAGAIN;
+ if (!crypto_is_larval(larval))
+ goto drop_larval;
+
+ ptype.attr.rta_len = sizeof(ptype);
+ ptype.attr.rta_type = CRYPTOA_TYPE;
+ ptype.data.type = type | CRYPTO_ALG_GENIV;
+ /* GENIV tells the template that we're making a default geniv. */
+ ptype.data.mask = mask | CRYPTO_ALG_GENIV;
+ tb[0] = &ptype.attr;
+
+ palg.attr.rta_len = sizeof(palg);
+ palg.attr.rta_type = CRYPTOA_ALG;
+ /* Must use the exact name to locate ourselves. */
+ memcpy(palg.data.name, alg->cra_driver_name, CRYPTO_MAX_ALG_NAME);
+ tb[1] = &palg.attr;
+
+ tb[2] = NULL;
+
+ if ((alg->cra_flags & CRYPTO_ALG_TYPE_MASK) ==
+ CRYPTO_ALG_TYPE_BLKCIPHER)
+ geniv = alg->cra_blkcipher.geniv;
+ else
+ geniv = alg->cra_ablkcipher.geniv;
+
+ if (!geniv)
+ geniv = crypto_default_geniv(alg);
+
+ tmpl = crypto_lookup_template(geniv);
+ err = -ENOENT;
+ if (!tmpl)
+ goto kill_larval;
+
+ inst = tmpl->alloc(tb);
+ err = PTR_ERR(inst);
+ if (IS_ERR(inst))
+ goto put_tmpl;
+
+ err = crypto_register_instance(tmpl, inst);
+ if (err) {
+ tmpl->free(inst);
+ goto put_tmpl;
+ }
+
+ /* Redo the lookup to use the instance we just registered. */
+ err = -EAGAIN;
+
+put_tmpl:
+ crypto_tmpl_put(tmpl);
+kill_larval:
+ crypto_larval_kill(larval);
+drop_larval:
+ crypto_mod_put(larval);
+out:
+ crypto_mod_put(alg);
+ return err;
+}
+
+struct crypto_alg *crypto_lookup_skcipher(const char *name, u32 type, u32 mask)
+{
+ struct crypto_alg *alg;
+
+ alg = crypto_alg_mod_lookup(name, type, mask);
+ if (IS_ERR(alg))
+ return alg;
+
+ if ((alg->cra_flags & CRYPTO_ALG_TYPE_MASK) ==
+ CRYPTO_ALG_TYPE_GIVCIPHER)
+ return alg;
+
+ if (!((alg->cra_flags & CRYPTO_ALG_TYPE_MASK) ==
+ CRYPTO_ALG_TYPE_BLKCIPHER ? alg->cra_blkcipher.ivsize :
+ alg->cra_ablkcipher.ivsize))
+ return alg;
+
+ crypto_mod_put(alg);
+ alg = crypto_alg_mod_lookup(name, type | CRYPTO_ALG_TESTED,
+ mask & ~CRYPTO_ALG_TESTED);
+ if (IS_ERR(alg))
+ return alg;
+
+ if ((alg->cra_flags & CRYPTO_ALG_TYPE_MASK) ==
+ CRYPTO_ALG_TYPE_GIVCIPHER) {
+ if ((alg->cra_flags ^ type ^ ~mask) & CRYPTO_ALG_TESTED) {
+ crypto_mod_put(alg);
+ alg = ERR_PTR(-ENOENT);
+ }
+ return alg;
+ }
+
+ BUG_ON(!((alg->cra_flags & CRYPTO_ALG_TYPE_MASK) ==
+ CRYPTO_ALG_TYPE_BLKCIPHER ? alg->cra_blkcipher.ivsize :
+ alg->cra_ablkcipher.ivsize));
+
+ return ERR_PTR(crypto_givcipher_default(alg, type, mask));
+}
+EXPORT_SYMBOL_GPL(crypto_lookup_skcipher);
+
+int crypto_grab_skcipher(struct crypto_skcipher_spawn *spawn, const char *name,
+ u32 type, u32 mask)
+{
+ struct crypto_alg *alg;
+ int err;
+
+ type = crypto_skcipher_type(type);
+ mask = crypto_skcipher_mask(mask);
+
+ alg = crypto_lookup_skcipher(name, type, mask);
+ if (IS_ERR(alg))
+ return PTR_ERR(alg);
+
+ err = crypto_init_spawn(&spawn->base, alg, spawn->base.inst, mask);
+ crypto_mod_put(alg);
+ return err;
+}
+EXPORT_SYMBOL_GPL(crypto_grab_skcipher);
+
+struct crypto_ablkcipher *crypto_alloc_ablkcipher(const char *alg_name,
+ u32 type, u32 mask)
+{
+ struct crypto_tfm *tfm;
+ int err;
+
+ type = crypto_skcipher_type(type);
+ mask = crypto_skcipher_mask(mask);
+
+ for (;;) {
+ struct crypto_alg *alg;
+
+ alg = crypto_lookup_skcipher(alg_name, type, mask);
+ if (IS_ERR(alg)) {
+ err = PTR_ERR(alg);
+ goto err;
+ }
+
+ tfm = __crypto_alloc_tfm(alg, type, mask);
+ if (!IS_ERR(tfm))
+ return __crypto_ablkcipher_cast(tfm);
+
+ crypto_mod_put(alg);
+ err = PTR_ERR(tfm);
+
+err:
+ if (err != -EAGAIN)
+ break;
+ if (signal_pending(current)) {
+ err = -EINTR;
+ break;
+ }
+ }
+
+ return ERR_PTR(err);
+}
+EXPORT_SYMBOL_GPL(crypto_alloc_ablkcipher);