linux/fs/ceph/crypto.c
Sage Weil 8b6e4f2d8b ceph: aes crypto and base64 encode/decode helpers
Helpers to encrypt/decrypt AES and base64.

Signed-off-by: Yehuda Sadeh <yehuda@hq.newdream.net>
Signed-off-by: Sage Weil <sage@newdream.net>
2010-02-10 15:04:46 -08:00

409 lines
10 KiB
C

#include "ceph_debug.h"
#include <linux/err.h>
#include <linux/scatterlist.h>
#include <crypto/hash.h>
#include "crypto.h"
#include "decode.h"
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);
}
const u8 *aes_iv = "cephsageyudagreg";
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], sg_out[1];
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;
crypto_blkcipher_setkey((void *)tfm, key, key_len);
sg_init_table(sg_in, 2);
sg_set_buf(&sg_in[0], src, src_len);
sg_set_buf(&sg_in[1], pad, zero_padding);
sg_init_table(sg_out, 1);
sg_set_buf(sg_out, dst, *dst_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, sg_in,
src_len + zero_padding);
crypto_free_blkcipher(tfm);
if (ret < 0)
pr_err("ceph_aes_crypt failed %d\n", ret);
/*
print_hex_dump(KERN_ERR, "enc out: ", DUMP_PREFIX_NONE, 16, 1,
dst, *dst_len, 1);
*/
return 0;
}
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], sg_out[1];
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;
crypto_blkcipher_setkey((void *)tfm, key, key_len);
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);
sg_init_table(sg_out, 1);
sg_set_buf(sg_out, dst, *dst_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, sg_in,
src1_len + src2_len + zero_padding);
crypto_free_blkcipher(tfm);
if (ret < 0)
pr_err("ceph_aes_crypt2 failed %d\n", ret);
/*
print_hex_dump(KERN_ERR, "enc out: ", DUMP_PREFIX_NONE, 16, 1,
dst, *dst_len, 1);
*/
return 0;
}
int ceph_aes_decrypt(const void *key, int key_len, void *dst, size_t *dst_len,
const void *src, size_t src_len)
{
struct scatterlist sg_in[1], sg_out[2];
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);
crypto_blkcipher_setkey((void *)tfm, key, key_len);
sg_init_table(sg_in, 1);
sg_init_table(sg_out, 2);
sg_set_buf(sg_in, src, src_len);
sg_set_buf(&sg_out[0], dst, *dst_len);
sg_set_buf(&sg_out[1], pad, sizeof(pad));
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, src_len);
crypto_free_blkcipher(tfm);
if (ret < 0) {
pr_err("ceph_aes_decrypt failed %d\n", ret);
return ret;
}
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);
*/
return 0;
}
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 scatterlist sg_in[1], sg_out[3];
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_in, 1);
sg_set_buf(sg_in, src, src_len);
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));
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, src_len);
crypto_free_blkcipher(tfm);
if (ret < 0) {
pr_err("ceph_aes_decrypt failed %d\n", ret);
return ret;
}
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);
*/
return 0;
}
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;
}
}