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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 /net/ceph/crypto.c
Initial import
Diffstat (limited to 'net/ceph/crypto.c')
-rw-r--r--net/ceph/crypto.c583
1 files changed, 583 insertions, 0 deletions
diff --git a/net/ceph/crypto.c b/net/ceph/crypto.c
new file mode 100644
index 000000000..790fe89d9
--- /dev/null
+++ b/net/ceph/crypto.c
@@ -0,0 +1,583 @@
+
+#include <linux/ceph/ceph_debug.h>
+
+#include <linux/err.h>
+#include <linux/scatterlist.h>
+#include <linux/slab.h>
+#include <crypto/hash.h>
+#include <linux/key-type.h>
+
+#include <keys/ceph-type.h>
+#include <keys/user-type.h>
+#include <linux/ceph/decode.h>
+#include "crypto.h"
+
+int ceph_crypto_key_clone(struct ceph_crypto_key *dst,
+ const struct ceph_crypto_key *src)
+{
+ memcpy(dst, src, sizeof(struct ceph_crypto_key));
+ dst->key = kmemdup(src->key, src->len, GFP_NOFS);
+ if (!dst->key)
+ return -ENOMEM;
+ return 0;
+}
+
+int ceph_crypto_key_encode(struct ceph_crypto_key *key, void **p, void *end)
+{
+ if (*p + sizeof(u16) + sizeof(key->created) +
+ sizeof(u16) + key->len > end)
+ return -ERANGE;
+ ceph_encode_16(p, key->type);
+ ceph_encode_copy(p, &key->created, sizeof(key->created));
+ ceph_encode_16(p, key->len);
+ ceph_encode_copy(p, key->key, key->len);
+ return 0;
+}
+
+int ceph_crypto_key_decode(struct ceph_crypto_key *key, void **p, void *end)
+{
+ ceph_decode_need(p, end, 2*sizeof(u16) + sizeof(key->created), bad);
+ key->type = ceph_decode_16(p);
+ ceph_decode_copy(p, &key->created, sizeof(key->created));
+ key->len = ceph_decode_16(p);
+ ceph_decode_need(p, end, key->len, bad);
+ key->key = kmalloc(key->len, GFP_NOFS);
+ if (!key->key)
+ return -ENOMEM;
+ ceph_decode_copy(p, key->key, key->len);
+ return 0;
+
+bad:
+ dout("failed to decode crypto key\n");
+ return -EINVAL;
+}
+
+int ceph_crypto_key_unarmor(struct ceph_crypto_key *key, const char *inkey)
+{
+ int inlen = strlen(inkey);
+ int blen = inlen * 3 / 4;
+ void *buf, *p;
+ int ret;
+
+ dout("crypto_key_unarmor %s\n", inkey);
+ buf = kmalloc(blen, GFP_NOFS);
+ if (!buf)
+ return -ENOMEM;
+ blen = ceph_unarmor(buf, inkey, inkey+inlen);
+ if (blen < 0) {
+ kfree(buf);
+ return blen;
+ }
+
+ p = buf;
+ ret = ceph_crypto_key_decode(key, &p, p + blen);
+ kfree(buf);
+ if (ret)
+ return ret;
+ dout("crypto_key_unarmor key %p type %d len %d\n", key,
+ key->type, key->len);
+ return 0;
+}
+
+
+
+#define AES_KEY_SIZE 16
+
+static struct crypto_blkcipher *ceph_crypto_alloc_cipher(void)
+{
+ return crypto_alloc_blkcipher("cbc(aes)", 0, CRYPTO_ALG_ASYNC);
+}
+
+static const u8 *aes_iv = (u8 *)CEPH_AES_IV;
+
+/*
+ * Should be used for buffers allocated with ceph_kvmalloc().
+ * Currently these are encrypt out-buffer (ceph_buffer) and decrypt
+ * in-buffer (msg front).
+ *
+ * Dispose of @sgt with teardown_sgtable().
+ *
+ * @prealloc_sg is to avoid memory allocation inside sg_alloc_table()
+ * in cases where a single sg is sufficient. No attempt to reduce the
+ * number of sgs by squeezing physically contiguous pages together is
+ * made though, for simplicity.
+ */
+static int setup_sgtable(struct sg_table *sgt, struct scatterlist *prealloc_sg,
+ const void *buf, unsigned int buf_len)
+{
+ struct scatterlist *sg;
+ const bool is_vmalloc = is_vmalloc_addr(buf);
+ unsigned int off = offset_in_page(buf);
+ unsigned int chunk_cnt = 1;
+ unsigned int chunk_len = PAGE_ALIGN(off + buf_len);
+ int i;
+ int ret;
+
+ if (buf_len == 0) {
+ memset(sgt, 0, sizeof(*sgt));
+ return -EINVAL;
+ }
+
+ if (is_vmalloc) {
+ chunk_cnt = chunk_len >> PAGE_SHIFT;
+ chunk_len = PAGE_SIZE;
+ }
+
+ if (chunk_cnt > 1) {
+ ret = sg_alloc_table(sgt, chunk_cnt, GFP_NOFS);
+ if (ret)
+ return ret;
+ } else {
+ WARN_ON(chunk_cnt != 1);
+ sg_init_table(prealloc_sg, 1);
+ sgt->sgl = prealloc_sg;
+ sgt->nents = sgt->orig_nents = 1;
+ }
+
+ for_each_sg(sgt->sgl, sg, sgt->orig_nents, i) {
+ struct page *page;
+ unsigned int len = min(chunk_len - off, buf_len);
+
+ if (is_vmalloc)
+ page = vmalloc_to_page(buf);
+ else
+ page = virt_to_page(buf);
+
+ sg_set_page(sg, page, len, off);
+
+ off = 0;
+ buf += len;
+ buf_len -= len;
+ }
+ WARN_ON(buf_len != 0);
+
+ return 0;
+}
+
+static void teardown_sgtable(struct sg_table *sgt)
+{
+ if (sgt->orig_nents > 1)
+ sg_free_table(sgt);
+}
+
+static int ceph_aes_encrypt(const void *key, int key_len,
+ void *dst, size_t *dst_len,
+ const void *src, size_t src_len)
+{
+ struct scatterlist sg_in[2], prealloc_sg;
+ struct sg_table sg_out;
+ struct crypto_blkcipher *tfm = ceph_crypto_alloc_cipher();
+ struct blkcipher_desc desc = { .tfm = tfm, .flags = 0 };
+ int ret;
+ void *iv;
+ int ivsize;
+ size_t zero_padding = (0x10 - (src_len & 0x0f));
+ char pad[16];
+
+ if (IS_ERR(tfm))
+ return PTR_ERR(tfm);
+
+ memset(pad, zero_padding, zero_padding);
+
+ *dst_len = src_len + zero_padding;
+
+ sg_init_table(sg_in, 2);
+ sg_set_buf(&sg_in[0], src, src_len);
+ sg_set_buf(&sg_in[1], pad, zero_padding);
+ ret = setup_sgtable(&sg_out, &prealloc_sg, dst, *dst_len);
+ if (ret)
+ goto out_tfm;
+
+ crypto_blkcipher_setkey((void *)tfm, key, key_len);
+ iv = crypto_blkcipher_crt(tfm)->iv;
+ ivsize = crypto_blkcipher_ivsize(tfm);
+ memcpy(iv, aes_iv, ivsize);
+
+ /*
+ print_hex_dump(KERN_ERR, "enc key: ", DUMP_PREFIX_NONE, 16, 1,
+ key, key_len, 1);
+ print_hex_dump(KERN_ERR, "enc src: ", DUMP_PREFIX_NONE, 16, 1,
+ src, src_len, 1);
+ print_hex_dump(KERN_ERR, "enc pad: ", DUMP_PREFIX_NONE, 16, 1,
+ pad, zero_padding, 1);
+ */
+ ret = crypto_blkcipher_encrypt(&desc, sg_out.sgl, sg_in,
+ src_len + zero_padding);
+ if (ret < 0) {
+ pr_err("ceph_aes_crypt failed %d\n", ret);
+ goto out_sg;
+ }
+ /*
+ print_hex_dump(KERN_ERR, "enc out: ", DUMP_PREFIX_NONE, 16, 1,
+ dst, *dst_len, 1);
+ */
+
+out_sg:
+ teardown_sgtable(&sg_out);
+out_tfm:
+ crypto_free_blkcipher(tfm);
+ return ret;
+}
+
+static int ceph_aes_encrypt2(const void *key, int key_len, void *dst,
+ size_t *dst_len,
+ const void *src1, size_t src1_len,
+ const void *src2, size_t src2_len)
+{
+ struct scatterlist sg_in[3], prealloc_sg;
+ struct sg_table sg_out;
+ struct crypto_blkcipher *tfm = ceph_crypto_alloc_cipher();
+ struct blkcipher_desc desc = { .tfm = tfm, .flags = 0 };
+ int ret;
+ void *iv;
+ int ivsize;
+ size_t zero_padding = (0x10 - ((src1_len + src2_len) & 0x0f));
+ char pad[16];
+
+ if (IS_ERR(tfm))
+ return PTR_ERR(tfm);
+
+ memset(pad, zero_padding, zero_padding);
+
+ *dst_len = src1_len + src2_len + zero_padding;
+
+ sg_init_table(sg_in, 3);
+ sg_set_buf(&sg_in[0], src1, src1_len);
+ sg_set_buf(&sg_in[1], src2, src2_len);
+ sg_set_buf(&sg_in[2], pad, zero_padding);
+ ret = setup_sgtable(&sg_out, &prealloc_sg, dst, *dst_len);
+ if (ret)
+ goto out_tfm;
+
+ crypto_blkcipher_setkey((void *)tfm, key, key_len);
+ iv = crypto_blkcipher_crt(tfm)->iv;
+ ivsize = crypto_blkcipher_ivsize(tfm);
+ memcpy(iv, aes_iv, ivsize);
+
+ /*
+ print_hex_dump(KERN_ERR, "enc key: ", DUMP_PREFIX_NONE, 16, 1,
+ key, key_len, 1);
+ print_hex_dump(KERN_ERR, "enc src1: ", DUMP_PREFIX_NONE, 16, 1,
+ src1, src1_len, 1);
+ print_hex_dump(KERN_ERR, "enc src2: ", DUMP_PREFIX_NONE, 16, 1,
+ src2, src2_len, 1);
+ print_hex_dump(KERN_ERR, "enc pad: ", DUMP_PREFIX_NONE, 16, 1,
+ pad, zero_padding, 1);
+ */
+ ret = crypto_blkcipher_encrypt(&desc, sg_out.sgl, sg_in,
+ src1_len + src2_len + zero_padding);
+ if (ret < 0) {
+ pr_err("ceph_aes_crypt2 failed %d\n", ret);
+ goto out_sg;
+ }
+ /*
+ print_hex_dump(KERN_ERR, "enc out: ", DUMP_PREFIX_NONE, 16, 1,
+ dst, *dst_len, 1);
+ */
+
+out_sg:
+ teardown_sgtable(&sg_out);
+out_tfm:
+ crypto_free_blkcipher(tfm);
+ return ret;
+}
+
+static int ceph_aes_decrypt(const void *key, int key_len,
+ void *dst, size_t *dst_len,
+ const void *src, size_t src_len)
+{
+ struct sg_table sg_in;
+ struct scatterlist sg_out[2], prealloc_sg;
+ struct crypto_blkcipher *tfm = ceph_crypto_alloc_cipher();
+ struct blkcipher_desc desc = { .tfm = tfm };
+ char pad[16];
+ void *iv;
+ int ivsize;
+ int ret;
+ int last_byte;
+
+ if (IS_ERR(tfm))
+ return PTR_ERR(tfm);
+
+ sg_init_table(sg_out, 2);
+ sg_set_buf(&sg_out[0], dst, *dst_len);
+ sg_set_buf(&sg_out[1], pad, sizeof(pad));
+ ret = setup_sgtable(&sg_in, &prealloc_sg, src, src_len);
+ if (ret)
+ goto out_tfm;
+
+ crypto_blkcipher_setkey((void *)tfm, key, key_len);
+ iv = crypto_blkcipher_crt(tfm)->iv;
+ ivsize = crypto_blkcipher_ivsize(tfm);
+ memcpy(iv, aes_iv, ivsize);
+
+ /*
+ print_hex_dump(KERN_ERR, "dec key: ", DUMP_PREFIX_NONE, 16, 1,
+ key, key_len, 1);
+ print_hex_dump(KERN_ERR, "dec in: ", DUMP_PREFIX_NONE, 16, 1,
+ src, src_len, 1);
+ */
+ ret = crypto_blkcipher_decrypt(&desc, sg_out, sg_in.sgl, src_len);
+ if (ret < 0) {
+ pr_err("ceph_aes_decrypt failed %d\n", ret);
+ goto out_sg;
+ }
+
+ if (src_len <= *dst_len)
+ last_byte = ((char *)dst)[src_len - 1];
+ else
+ last_byte = pad[src_len - *dst_len - 1];
+ if (last_byte <= 16 && src_len >= last_byte) {
+ *dst_len = src_len - last_byte;
+ } else {
+ pr_err("ceph_aes_decrypt got bad padding %d on src len %d\n",
+ last_byte, (int)src_len);
+ return -EPERM; /* bad padding */
+ }
+ /*
+ print_hex_dump(KERN_ERR, "dec out: ", DUMP_PREFIX_NONE, 16, 1,
+ dst, *dst_len, 1);
+ */
+
+out_sg:
+ teardown_sgtable(&sg_in);
+out_tfm:
+ crypto_free_blkcipher(tfm);
+ return ret;
+}
+
+static int ceph_aes_decrypt2(const void *key, int key_len,
+ void *dst1, size_t *dst1_len,
+ void *dst2, size_t *dst2_len,
+ const void *src, size_t src_len)
+{
+ struct sg_table sg_in;
+ struct scatterlist sg_out[3], prealloc_sg;
+ struct crypto_blkcipher *tfm = ceph_crypto_alloc_cipher();
+ struct blkcipher_desc desc = { .tfm = tfm };
+ char pad[16];
+ void *iv;
+ int ivsize;
+ int ret;
+ int last_byte;
+
+ if (IS_ERR(tfm))
+ return PTR_ERR(tfm);
+
+ sg_init_table(sg_out, 3);
+ sg_set_buf(&sg_out[0], dst1, *dst1_len);
+ sg_set_buf(&sg_out[1], dst2, *dst2_len);
+ sg_set_buf(&sg_out[2], pad, sizeof(pad));
+ ret = setup_sgtable(&sg_in, &prealloc_sg, src, src_len);
+ if (ret)
+ goto out_tfm;
+
+ crypto_blkcipher_setkey((void *)tfm, key, key_len);
+ iv = crypto_blkcipher_crt(tfm)->iv;
+ ivsize = crypto_blkcipher_ivsize(tfm);
+ memcpy(iv, aes_iv, ivsize);
+
+ /*
+ print_hex_dump(KERN_ERR, "dec key: ", DUMP_PREFIX_NONE, 16, 1,
+ key, key_len, 1);
+ print_hex_dump(KERN_ERR, "dec in: ", DUMP_PREFIX_NONE, 16, 1,
+ src, src_len, 1);
+ */
+ ret = crypto_blkcipher_decrypt(&desc, sg_out, sg_in.sgl, src_len);
+ if (ret < 0) {
+ pr_err("ceph_aes_decrypt failed %d\n", ret);
+ goto out_sg;
+ }
+
+ if (src_len <= *dst1_len)
+ last_byte = ((char *)dst1)[src_len - 1];
+ else if (src_len <= *dst1_len + *dst2_len)
+ last_byte = ((char *)dst2)[src_len - *dst1_len - 1];
+ else
+ last_byte = pad[src_len - *dst1_len - *dst2_len - 1];
+ if (last_byte <= 16 && src_len >= last_byte) {
+ src_len -= last_byte;
+ } else {
+ pr_err("ceph_aes_decrypt got bad padding %d on src len %d\n",
+ last_byte, (int)src_len);
+ return -EPERM; /* bad padding */
+ }
+
+ if (src_len < *dst1_len) {
+ *dst1_len = src_len;
+ *dst2_len = 0;
+ } else {
+ *dst2_len = src_len - *dst1_len;
+ }
+ /*
+ print_hex_dump(KERN_ERR, "dec out1: ", DUMP_PREFIX_NONE, 16, 1,
+ dst1, *dst1_len, 1);
+ print_hex_dump(KERN_ERR, "dec out2: ", DUMP_PREFIX_NONE, 16, 1,
+ dst2, *dst2_len, 1);
+ */
+
+out_sg:
+ teardown_sgtable(&sg_in);
+out_tfm:
+ crypto_free_blkcipher(tfm);
+ return ret;
+}
+
+
+int ceph_decrypt(struct ceph_crypto_key *secret, void *dst, size_t *dst_len,
+ const void *src, size_t src_len)
+{
+ switch (secret->type) {
+ case CEPH_CRYPTO_NONE:
+ if (*dst_len < src_len)
+ return -ERANGE;
+ memcpy(dst, src, src_len);
+ *dst_len = src_len;
+ return 0;
+
+ case CEPH_CRYPTO_AES:
+ return ceph_aes_decrypt(secret->key, secret->len, dst,
+ dst_len, src, src_len);
+
+ default:
+ return -EINVAL;
+ }
+}
+
+int ceph_decrypt2(struct ceph_crypto_key *secret,
+ void *dst1, size_t *dst1_len,
+ void *dst2, size_t *dst2_len,
+ const void *src, size_t src_len)
+{
+ size_t t;
+
+ switch (secret->type) {
+ case CEPH_CRYPTO_NONE:
+ if (*dst1_len + *dst2_len < src_len)
+ return -ERANGE;
+ t = min(*dst1_len, src_len);
+ memcpy(dst1, src, t);
+ *dst1_len = t;
+ src += t;
+ src_len -= t;
+ if (src_len) {
+ t = min(*dst2_len, src_len);
+ memcpy(dst2, src, t);
+ *dst2_len = t;
+ }
+ return 0;
+
+ case CEPH_CRYPTO_AES:
+ return ceph_aes_decrypt2(secret->key, secret->len,
+ dst1, dst1_len, dst2, dst2_len,
+ src, src_len);
+
+ default:
+ return -EINVAL;
+ }
+}
+
+int ceph_encrypt(struct ceph_crypto_key *secret, void *dst, size_t *dst_len,
+ const void *src, size_t src_len)
+{
+ switch (secret->type) {
+ case CEPH_CRYPTO_NONE:
+ if (*dst_len < src_len)
+ return -ERANGE;
+ memcpy(dst, src, src_len);
+ *dst_len = src_len;
+ return 0;
+
+ case CEPH_CRYPTO_AES:
+ return ceph_aes_encrypt(secret->key, secret->len, dst,
+ dst_len, src, src_len);
+
+ default:
+ return -EINVAL;
+ }
+}
+
+int ceph_encrypt2(struct ceph_crypto_key *secret, void *dst, size_t *dst_len,
+ const void *src1, size_t src1_len,
+ const void *src2, size_t src2_len)
+{
+ switch (secret->type) {
+ case CEPH_CRYPTO_NONE:
+ if (*dst_len < src1_len + src2_len)
+ return -ERANGE;
+ memcpy(dst, src1, src1_len);
+ memcpy(dst + src1_len, src2, src2_len);
+ *dst_len = src1_len + src2_len;
+ return 0;
+
+ case CEPH_CRYPTO_AES:
+ return ceph_aes_encrypt2(secret->key, secret->len, dst, dst_len,
+ src1, src1_len, src2, src2_len);
+
+ default:
+ return -EINVAL;
+ }
+}
+
+static int ceph_key_preparse(struct key_preparsed_payload *prep)
+{
+ struct ceph_crypto_key *ckey;
+ size_t datalen = prep->datalen;
+ int ret;
+ void *p;
+
+ ret = -EINVAL;
+ if (datalen <= 0 || datalen > 32767 || !prep->data)
+ goto err;
+
+ ret = -ENOMEM;
+ ckey = kmalloc(sizeof(*ckey), GFP_KERNEL);
+ if (!ckey)
+ goto err;
+
+ /* TODO ceph_crypto_key_decode should really take const input */
+ p = (void *)prep->data;
+ ret = ceph_crypto_key_decode(ckey, &p, (char*)prep->data+datalen);
+ if (ret < 0)
+ goto err_ckey;
+
+ prep->payload[0] = ckey;
+ prep->quotalen = datalen;
+ return 0;
+
+err_ckey:
+ kfree(ckey);
+err:
+ return ret;
+}
+
+static void ceph_key_free_preparse(struct key_preparsed_payload *prep)
+{
+ struct ceph_crypto_key *ckey = prep->payload[0];
+ ceph_crypto_key_destroy(ckey);
+ kfree(ckey);
+}
+
+static void ceph_key_destroy(struct key *key)
+{
+ struct ceph_crypto_key *ckey = key->payload.data;
+
+ ceph_crypto_key_destroy(ckey);
+ kfree(ckey);
+}
+
+struct key_type key_type_ceph = {
+ .name = "ceph",
+ .preparse = ceph_key_preparse,
+ .free_preparse = ceph_key_free_preparse,
+ .instantiate = generic_key_instantiate,
+ .destroy = ceph_key_destroy,
+};
+
+int ceph_crypto_init(void) {
+ return register_key_type(&key_type_ceph);
+}
+
+void ceph_crypto_shutdown(void) {
+ unregister_key_type(&key_type_ceph);
+}