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| author | David Howells <dhowells@redhat.com> | 2019-05-30 15:53:10 +0200 |
|---|---|---|
| committer | David Howells <dhowells@redhat.com> | 2019-06-19 14:27:45 +0200 |
| commit | 45e0f30c30bb131663fbe1752974d6f2e39611e2 (patch) | |
| tree | 7679786ee974e03e277c871e68491921e491cdd8 /security/keys/keyctl.c | |
| parent | keys: Reuse keyring_index_key::desc_len in lookup_user_key() (diff) | |
| download | linux-45e0f30c30bb131663fbe1752974d6f2e39611e2.tar.xz linux-45e0f30c30bb131663fbe1752974d6f2e39611e2.zip | |
keys: Add capability-checking keyctl function
Add a keyctl function that requests a set of capability bits to find out
what features are supported.
Signed-off-by: David Howells <dhowells@redhat.com>
Diffstat (limited to 'security/keys/keyctl.c')
| -rw-r--r-- | security/keys/keyctl.c | 35 |
1 files changed, 35 insertions, 0 deletions
diff --git a/security/keys/keyctl.c b/security/keys/keyctl.c index bbfe7d92d41c..9f418e66f067 100644 --- a/security/keys/keyctl.c +++ b/security/keys/keyctl.c @@ -30,6 +30,18 @@ #define KEY_MAX_DESC_SIZE 4096 +static const unsigned char keyrings_capabilities[1] = { + [0] = (KEYCTL_CAPS0_CAPABILITIES | + (IS_ENABLED(CONFIG_PERSISTENT_KEYRINGS) ? KEYCTL_CAPS0_PERSISTENT_KEYRINGS : 0) | + (IS_ENABLED(CONFIG_KEY_DH_OPERATIONS) ? KEYCTL_CAPS0_DIFFIE_HELLMAN : 0) | + (IS_ENABLED(CONFIG_ASYMMETRIC_KEY_TYPE) ? KEYCTL_CAPS0_PUBLIC_KEY : 0) | + (IS_ENABLED(CONFIG_BIG_KEYS) ? KEYCTL_CAPS0_BIG_KEY : 0) | + KEYCTL_CAPS0_INVALIDATE | + KEYCTL_CAPS0_RESTRICT_KEYRING | + KEYCTL_CAPS0_MOVE + ), +}; + static int key_get_type_from_user(char *type, const char __user *_type, unsigned len) @@ -1679,6 +1691,26 @@ error: } /* + * Get keyrings subsystem capabilities. + */ +long keyctl_capabilities(unsigned char __user *_buffer, size_t buflen) +{ + size_t size = buflen; + + if (size > 0) { + if (size > sizeof(keyrings_capabilities)) + size = sizeof(keyrings_capabilities); + if (copy_to_user(_buffer, keyrings_capabilities, size) != 0) + return -EFAULT; + if (size < buflen && + clear_user(_buffer + size, buflen - size) != 0) + return -EFAULT; + } + + return sizeof(keyrings_capabilities); +} + +/* * The key control system call */ SYSCALL_DEFINE5(keyctl, int, option, unsigned long, arg2, unsigned long, arg3, @@ -1824,6 +1856,9 @@ SYSCALL_DEFINE5(keyctl, int, option, unsigned long, arg2, unsigned long, arg3, (key_serial_t)arg4, (unsigned int)arg5); + case KEYCTL_CAPABILITIES: + return keyctl_capabilities((unsigned char __user *)arg2, (size_t)arg3); + default: return -EOPNOTSUPP; } |