C++ crypto_shash_update函数代码示例

static int crypt_iv_lmk_one(struct crypt_config *cc, u8 *iv,
			    struct dm_crypt_request *dmreq,
			    u8 *data)
{
	struct iv_lmk_private *lmk = &cc->iv_gen_private.lmk;
	struct {
		struct shash_desc desc;
		char ctx[crypto_shash_descsize(lmk->hash_tfm)];
	} sdesc;
	struct md5_state md5state;
	u32 buf[4];
	int i, r;

	sdesc.desc.tfm = lmk->hash_tfm;
	sdesc.desc.flags = CRYPTO_TFM_REQ_MAY_SLEEP;

	r = crypto_shash_init(&sdesc.desc);
	if (r)
		return r;

	if (lmk->seed) {
		r = crypto_shash_update(&sdesc.desc, lmk->seed, LMK_SEED_SIZE);
		if (r)
			return r;
	}

	/* Sector is always 512B, block size 16, add data of blocks 1-31 */
	r = crypto_shash_update(&sdesc.desc, data + 16, 16 * 31);
	if (r)
		return r;

	/* Sector is cropped to 56 bits here */
	buf[0] = cpu_to_le32(dmreq->iv_sector & 0xFFFFFFFF);
	buf[1] = cpu_to_le32((((u64)dmreq->iv_sector >> 32) & 0x00FFFFFF) | 0x80000000);
	buf[2] = cpu_to_le32(4024);
	buf[3] = 0;
	r = crypto_shash_update(&sdesc.desc, (u8 *)buf, sizeof(buf));
	if (r)
		return r;

	/* No MD5 padding here */
	r = crypto_shash_export(&sdesc.desc, &md5state);
	if (r)
		return r;

	for (i = 0; i < MD5_HASH_WORDS; i++)
		__cpu_to_le32s(&md5state.hash[i]);
	memcpy(iv, &md5state.hash, cc->iv_size);

	return 0;
}

/*
 * Calculate the HMAC value across the set of protected security xattrs.
 *
 * Instead of retrieving the requested xattr, for performance, calculate
 * the hmac using the requested xattr value. Don't alloc/free memory for
 * each xattr, but attempt to re-use the previously allocated memory.
 */
static int evm_calc_hmac_or_hash(struct dentry *dentry,
				const char *req_xattr_name,
				const char *req_xattr_value,
				size_t req_xattr_value_len,
				char type, char *digest)
{
	struct inode *inode = dentry->d_inode;
	struct shash_desc *desc;
	char **xattrname;
	size_t xattr_size = 0;
	char *xattr_value = NULL;
	int error;
	int size;

	if (!inode->i_op || !inode->i_op->getxattr)
		return -EOPNOTSUPP;
	desc = init_desc(type);
	if (IS_ERR(desc))
		return PTR_ERR(desc);

	error = -ENODATA;
	for (xattrname = evm_config_xattrnames; *xattrname != NULL; xattrname++) {
		if ((req_xattr_name && req_xattr_value)
		    && !strcmp(*xattrname, req_xattr_name)) {
			error = 0;
			crypto_shash_update(desc, (const u8 *)req_xattr_value,
					     req_xattr_value_len);
			continue;
		}
		size = vfs_getxattr_alloc(dentry, *xattrname,
					  &xattr_value, xattr_size, GFP_NOFS);
		if (size == -ENOMEM) {
			error = -ENOMEM;
			goto out;
		}
		if (size < 0)
			continue;

		error = 0;
		xattr_size = size;
		crypto_shash_update(desc, (const u8 *)xattr_value, xattr_size);
	}
	hmac_add_misc(desc, inode, digest);

out:
	kfree(xattr_value);
	kfree(desc);
	return error;
}

static int calc_buffer_shash_tfm(const void *buf, loff_t size,
				struct ima_digest_data *hash,
				struct crypto_shash *tfm)
{
	SHASH_DESC_ON_STACK(shash, tfm);
	unsigned int len;
	int rc;

	shash->tfm = tfm;
	shash->flags = 0;

	hash->length = crypto_shash_digestsize(tfm);

	rc = crypto_shash_init(shash);
	if (rc != 0)
		return rc;

	while (size) {
		len = size < PAGE_SIZE ? size : PAGE_SIZE;
		rc = crypto_shash_update(shash, buf, len);
		if (rc)
			break;
		buf += len;
		size -= len;
	}

	if (!rc)
		rc = crypto_shash_final(shash, hash->digest);
	return rc;
}

char *aa_calc_hash(void *data, size_t len)
{
	SHASH_DESC_ON_STACK(desc, apparmor_tfm);
	char *hash = NULL;
	int error = -ENOMEM;

	if (!apparmor_tfm)
		return NULL;

	hash = kzalloc(apparmor_hash_size, GFP_KERNEL);
	if (!hash)
		goto fail;

	desc->tfm = apparmor_tfm;

	error = crypto_shash_init(desc);
	if (error)
		goto fail;
	error = crypto_shash_update(desc, (u8 *) data, len);
	if (error)
		goto fail;
	error = crypto_shash_final(desc, hash);
	if (error)
		goto fail;

	return hash;

fail:
	kfree(hash);

	return ERR_PTR(error);
}

static int mv_hash_final_fallback(struct ahash_request *req)
{
	const struct mv_tfm_hash_ctx *tfm_ctx = crypto_tfm_ctx(req->base.tfm);
	struct mv_req_hash_ctx *req_ctx = ahash_request_ctx(req);
	struct {
		struct shash_desc shash;
		char ctx[crypto_shash_descsize(tfm_ctx->fallback)];
	} desc;
	int rc;

	desc.shash.tfm = tfm_ctx->fallback;
	desc.shash.flags = CRYPTO_TFM_REQ_MAY_SLEEP;
	if (unlikely(req_ctx->first_hash)) {
		crypto_shash_init(&desc.shash);
		crypto_shash_update(&desc.shash, req_ctx->buffer,
				    req_ctx->extra_bytes);
	} else {
		/* only SHA1 for now....
		 */
		rc = mv_hash_import_sha1_ctx(req_ctx, &desc.shash);
		if (rc)
			goto out;
	}
	rc = crypto_shash_final(&desc.shash, req->result);
out:
	return rc;
}

static int
CalcNTLMv2_response(const struct cifsSesInfo *ses, char *ntlmv2_hash)
{
	int rc;
	unsigned int offset = CIFS_SESS_KEY_SIZE + 8;

	if (!ses->server->secmech.sdeschmacmd5) {
		cERROR(1, "calc_ntlmv2_hash: can't generate ntlmv2 hash\n");
		return -1;
	}

	crypto_shash_setkey(ses->server->secmech.hmacmd5,
				ntlmv2_hash, CIFS_HMAC_MD5_HASH_SIZE);

	rc = crypto_shash_init(&ses->server->secmech.sdeschmacmd5->shash);
	if (rc) {
		cERROR(1, "CalcNTLMv2_response: could not init hmacmd5");
		return rc;
	}

	if (ses->server->secType == RawNTLMSSP)
		memcpy(ses->auth_key.response + offset,
			ses->ntlmssp->cryptkey, CIFS_SERVER_CHALLENGE_SIZE);
	else
		memcpy(ses->auth_key.response + offset,
			ses->server->cryptkey, CIFS_SERVER_CHALLENGE_SIZE);
	crypto_shash_update(&ses->server->secmech.sdeschmacmd5->shash,
		ses->auth_key.response + offset, ses->auth_key.len - offset);

	rc = crypto_shash_final(&ses->server->secmech.sdeschmacmd5->shash,
		ses->auth_key.response + CIFS_SESS_KEY_SIZE);

	return rc;
}

static int cifs_calc_signature2(const struct kvec *iov, int n_vec,
				struct TCP_Server_Info *server, char *signature)
{
	int i;
	int rc;

	if (iov == NULL || signature == NULL || server == NULL)
		return -EINVAL;

	if (!server->secmech.sdescmd5) {
		cERROR(1, "%s: Can't generate signature\n", __func__);
		return -1;
	}

	rc = crypto_shash_init(&server->secmech.sdescmd5->shash);
	if (rc) {
		cERROR(1, "%s: Oould not init md5\n", __func__);
		return rc;
	}

	crypto_shash_update(&server->secmech.sdescmd5->shash,
		server->session_key.response, server->session_key.len);

	for (i = 0; i < n_vec; i++) {
		if (iov[i].iov_len == 0)
			continue;
		if (iov[i].iov_base == NULL) {
			cERROR(1, "null iovec entry");
			return -EIO;
		}
		/* The first entry includes a length field (which does not get
		   signed that occupies the first 4 bytes before the header */
		if (i == 0) {
			if (iov[0].iov_len <= 8) /* cmd field at offset 9 */
				break; /* nothing to sign or corrupt header */
			crypto_shash_update(&server->secmech.sdescmd5->shash,
				iov[i].iov_base + 4, iov[i].iov_len - 4);
		} else
			crypto_shash_update(&server->secmech.sdescmd5->shash,
				iov[i].iov_base, iov[i].iov_len);
	}

	rc = crypto_shash_final(&server->secmech.sdescmd5->shash, signature);

	return rc;
}

static int padlock_sha_update(struct shash_desc *desc,
			      const u8 *data, unsigned int length)
{
	struct padlock_sha_desc *dctx = shash_desc_ctx(desc);

	dctx->fallback.flags = desc->flags & CRYPTO_TFM_REQ_MAY_SLEEP;
	return crypto_shash_update(&dctx->fallback, data, length);
}

/*
 * Calculate the hash of template data
 */
static int ima_calc_field_array_hash_tfm(struct ima_field_data *field_data,
					 struct ima_template_desc *td,
					 int num_fields,
					 struct ima_digest_data *hash,
					 struct crypto_shash *tfm)
{
	SHASH_DESC_ON_STACK(shash, tfm);
	int rc, i;

	shash->tfm = tfm;
	shash->flags = 0;

	hash->length = crypto_shash_digestsize(tfm);

	rc = crypto_shash_init(shash);
	if (rc != 0)
		return rc;

	for (i = 0; i < num_fields; i++) {
		u8 buffer[IMA_EVENT_NAME_LEN_MAX + 1] = { 0 };
		u8 *data_to_hash = field_data[i].data;
		u32 datalen = field_data[i].len;
		u32 datalen_to_hash =
		    !ima_canonical_fmt ? datalen : cpu_to_le32(datalen);

		if (strcmp(td->name, IMA_TEMPLATE_IMA_NAME) != 0) {
			rc = crypto_shash_update(shash,
						(const u8 *) &datalen_to_hash,
						sizeof(datalen_to_hash));
			if (rc)
				break;
		} else if (strcmp(td->fields[i]->field_id, "n") == 0) {
			memcpy(buffer, data_to_hash, datalen);
			data_to_hash = buffer;
			datalen = IMA_EVENT_NAME_LEN_MAX + 1;
		}
		rc = crypto_shash_update(shash, data_to_hash, datalen);
		if (rc)
			break;
	}

	if (!rc)
		rc = crypto_shash_final(shash, hash->digest);

	return rc;
}

int orinoco_mic(struct crypto_shash *tfm_michael, u8 *key,
		u8 *da, u8 *sa, u8 priority,
		u8 *data, size_t data_len, u8 *mic)
{
	SHASH_DESC_ON_STACK(desc, tfm_michael);
	u8 hdr[ETH_HLEN + 2]; /* size of header + padding */
	int err;

	if (tfm_michael == NULL) {
		printk(KERN_WARNING "orinoco_mic: tfm_michael == NULL\n");
		return -1;
	}

	/* Copy header into buffer. We need the padding on the end zeroed */
	memcpy(&hdr[0], da, ETH_ALEN);
	memcpy(&hdr[ETH_ALEN], sa, ETH_ALEN);
	hdr[ETH_ALEN * 2] = priority;
	hdr[ETH_ALEN * 2 + 1] = 0;
	hdr[ETH_ALEN * 2 + 2] = 0;
	hdr[ETH_ALEN * 2 + 3] = 0;

	desc->tfm = tfm_michael;
	desc->flags = 0;

	err = crypto_shash_setkey(tfm_michael, key, MIC_KEYLEN);
	if (err)
		return err;

	err = crypto_shash_init(desc);
	if (err)
		return err;

	err = crypto_shash_update(desc, hdr, sizeof(hdr));
	if (err)
		return err;

	err = crypto_shash_update(desc, data, data_len);
	if (err)
		return err;

	err = crypto_shash_final(desc, mic);
	shash_desc_zero(desc);

	return err;
}

static int ima_calc_file_hash_tfm(struct file *file,
				  struct ima_digest_data *hash,
				  struct crypto_shash *tfm)
{
	loff_t i_size, offset = 0;
	char *rbuf;
	int rc, read = 0;
	SHASH_DESC_ON_STACK(shash, tfm);

	shash->tfm = tfm;
	shash->flags = 0;

	hash->length = crypto_shash_digestsize(tfm);

	rc = crypto_shash_init(shash);
	if (rc != 0)
		return rc;

	i_size = i_size_read(file_inode(file));

	if (i_size == 0)
		goto out;

	rbuf = kzalloc(PAGE_SIZE, GFP_KERNEL);
	if (!rbuf)
		return -ENOMEM;

	if (!(file->f_mode & FMODE_READ)) {
		file->f_mode |= FMODE_READ;
		read = 1;
	}

	while (offset < i_size) {
		int rbuf_len;

		rbuf_len = integrity_kernel_read(file, offset, rbuf, PAGE_SIZE);
		if (rbuf_len < 0) {
			rc = rbuf_len;
			break;
		}
		if (rbuf_len == 0)
			break;
		offset += rbuf_len;

		rc = crypto_shash_update(shash, rbuf, rbuf_len);
		if (rc)
			break;
	}
	if (read)
		file->f_mode &= ~FMODE_READ;
	kfree(rbuf);
out:
	if (!rc)
		rc = crypto_shash_final(shash, hash->digest);
	return rc;
}

int aa_calc_profile_hash(struct aa_profile *profile, u32 version, void *start,
			 size_t len)
{
	SHASH_DESC_ON_STACK(desc, apparmor_tfm);
	int error = -ENOMEM;
	__le32 le32_version = cpu_to_le32(version);

	if (!aa_g_hash_policy)
		return 0;

	if (!apparmor_tfm)
		return 0;

	profile->hash = kzalloc(apparmor_hash_size, GFP_KERNEL);
	if (!profile->hash)
		goto fail;

	desc->tfm = apparmor_tfm;

	error = crypto_shash_init(desc);
	if (error)
		goto fail;
	error = crypto_shash_update(desc, (u8 *) &le32_version, 4);
	if (error)
		goto fail;
	error = crypto_shash_update(desc, (u8 *) start, len);
	if (error)
		goto fail;
	error = crypto_shash_final(desc, profile->hash);
	if (error)
		goto fail;

	return 0;

fail:
	kfree(profile->hash);
	profile->hash = NULL;

	return error;
}

/*
 * Calculate and return the CIFS signature based on the mac key and SMB PDU.
 * The 16 byte signature must be allocated by the caller. Note we only use the
 * 1st eight bytes and that the smb header signature field on input contains
 * the sequence number before this function is called. Also, this function
 * should be called with the server->srv_mutex held.
 */
static int cifs_calculate_signature(const struct smb_hdr *cifs_pdu,
				struct TCP_Server_Info *server, char *signature)
{
	int rc;

	if (cifs_pdu == NULL || signature == NULL || server == NULL)
		return -EINVAL;

	if (!server->secmech.sdescmd5) {
		cERROR(1, "%s: Can't generate signature\n", __func__);
		return -1;
	}

	rc = crypto_shash_init(&server->secmech.sdescmd5->shash);
	if (rc) {
		cERROR(1, "%s: Could not init md5\n", __func__);
		return rc;
	}

	rc = crypto_shash_update(&server->secmech.sdescmd5->shash,
		server->session_key.response, server->session_key.len);
	if (rc) {
		cERROR(1, "%s: Could not update with response\n", __func__);
		return rc;
	}

	rc = crypto_shash_update(&server->secmech.sdescmd5->shash,
		cifs_pdu->Protocol, be32_to_cpu(cifs_pdu->smb_buf_length));
	if (rc) {
		cERROR(1, "%s: Could not update with payload\n", __func__);
		return rc;
	}

	rc = crypto_shash_final(&server->secmech.sdescmd5->shash, signature);
	if (rc)
		cERROR(1, "%s: Could not generate md5 hash\n", __func__);

	return rc;
}

/* Protect against 'cutting & pasting' security.evm xattr, include inode
 * specific info.
 *
 * (Additional directory/file metadata needs to be added for more complete
 * protection.)
 */
static void hmac_add_misc(struct shash_desc *desc, struct inode *inode,
			  char *digest)
{
	struct h_misc {
		unsigned long ino;
		__u32 generation;
		uid_t uid;
		gid_t gid;
		umode_t mode;
	} hmac_misc;

	memset(&hmac_misc, 0, sizeof(hmac_misc));
	hmac_misc.ino = inode->i_ino;
	hmac_misc.generation = inode->i_generation;
	hmac_misc.uid = from_kuid(&init_user_ns, inode->i_uid);
	hmac_misc.gid = from_kgid(&init_user_ns, inode->i_gid);
	hmac_misc.mode = inode->i_mode;
	crypto_shash_update(desc, (const u8 *)&hmac_misc, sizeof(hmac_misc));
	if (evm_hmac_version > 1)
		crypto_shash_update(desc, inode->i_sb->s_uuid,
				    sizeof(inode->i_sb->s_uuid));
	crypto_shash_final(desc, digest);
}

u32 crc32c(u32 crc, const void *address, unsigned int length)
{
	SHASH_DESC_ON_STACK(shash, tfm);
	u32 *ctx = (u32 *)shash_desc_ctx(shash);
	int err;

	shash->tfm = tfm;
	shash->flags = 0;
	*ctx = crc;

	err = crypto_shash_update(shash, address, length);
	BUG_ON(err);

	return *ctx;
}