diff options
Diffstat (limited to 'fs/crypto/policy.c')
| -rw-r--r-- | fs/crypto/policy.c | 41 |
1 files changed, 40 insertions, 1 deletions
diff --git a/fs/crypto/policy.c b/fs/crypto/policy.c index 4072ba644595..96f528071bed 100644 --- a/fs/crypto/policy.c +++ b/fs/crypto/policy.c @@ -29,6 +29,40 @@ bool fscrypt_policies_equal(const union fscrypt_policy *policy1, return !memcmp(policy1, policy2, fscrypt_policy_size(policy1)); } +static bool supported_iv_ino_lblk_64_policy( + const struct fscrypt_policy_v2 *policy, + const struct inode *inode) +{ + struct super_block *sb = inode->i_sb; + int ino_bits = 64, lblk_bits = 64; + + if (policy->flags & FSCRYPT_POLICY_FLAG_DIRECT_KEY) { + fscrypt_warn(inode, + "The DIRECT_KEY and IV_INO_LBLK_64 flags are mutually exclusive"); + return false; + } + /* + * It's unsafe to include inode numbers in the IVs if the filesystem can + * potentially renumber inodes, e.g. via filesystem shrinking. + */ + if (!sb->s_cop->has_stable_inodes || + !sb->s_cop->has_stable_inodes(sb)) { + fscrypt_warn(inode, + "Can't use IV_INO_LBLK_64 policy on filesystem '%s' because it doesn't have stable inode numbers", + sb->s_id); + return false; + } + if (sb->s_cop->get_ino_and_lblk_bits) + sb->s_cop->get_ino_and_lblk_bits(sb, &ino_bits, &lblk_bits); + if (ino_bits > 32 || lblk_bits > 32) { + fscrypt_warn(inode, + "Can't use IV_INO_LBLK_64 policy on filesystem '%s' because it doesn't use 32-bit inode and block numbers", + sb->s_id); + return false; + } + return true; +} + /** * fscrypt_supported_policy - check whether an encryption policy is supported * @@ -55,7 +89,8 @@ bool fscrypt_supported_policy(const union fscrypt_policy *policy_u, return false; } - if (policy->flags & ~FSCRYPT_POLICY_FLAGS_VALID) { + if (policy->flags & ~(FSCRYPT_POLICY_FLAGS_PAD_MASK | + FSCRYPT_POLICY_FLAG_DIRECT_KEY)) { fscrypt_warn(inode, "Unsupported encryption flags (0x%02x)", policy->flags); @@ -83,6 +118,10 @@ bool fscrypt_supported_policy(const union fscrypt_policy *policy_u, return false; } + if ((policy->flags & FSCRYPT_POLICY_FLAG_IV_INO_LBLK_64) && + !supported_iv_ino_lblk_64_policy(policy, inode)) + return false; + if (memchr_inv(policy->__reserved, 0, sizeof(policy->__reserved))) { fscrypt_warn(inode, |