diff options
| -rw-r--r-- | Documentation/keys.txt | 15 | ||||
| -rw-r--r-- | arch/x86/Kconfig | 5 | ||||
| -rw-r--r-- | include/linux/keyctl.h | 1 | ||||
| -rw-r--r-- | security/keys/compat.c | 47 | ||||
| -rw-r--r-- | security/keys/internal.h | 7 | ||||
| -rw-r--r-- | security/keys/keyctl.c | 103 |
6 files changed, 167 insertions, 11 deletions
diff --git a/Documentation/keys.txt b/Documentation/keys.txt index a6a97fdfadd..6523a9e6f29 100644 --- a/Documentation/keys.txt +++ b/Documentation/keys.txt @@ -637,6 +637,9 @@ The keyctl syscall functions are: long keyctl(KEYCTL_INSTANTIATE, key_serial_t key, const void *payload, size_t plen, key_serial_t keyring); + long keyctl(KEYCTL_INSTANTIATE_IOV, key_serial_t key, + const struct iovec *payload_iov, unsigned ioc, + key_serial_t keyring); If the kernel calls back to userspace to complete the instantiation of a key, userspace should use this call to supply data for the key before the @@ -652,6 +655,9 @@ The keyctl syscall functions are: The payload and plen arguments describe the payload data as for add_key(). + The payload_iov and ioc arguments describe the payload data in an iovec + array instead of a single buffer. + (*) Negatively instantiate a partially constructed key. @@ -1244,10 +1250,11 @@ hand the request off to (perhaps a path held in placed in another key by, for example, the KDE desktop manager). The program (or whatever it calls) should finish construction of the key by -calling KEYCTL_INSTANTIATE, which also permits it to cache the key in one of -the keyrings (probably the session ring) before returning. Alternatively, the -key can be marked as negative with KEYCTL_NEGATE or KEYCTL_REJECT; this also -permits the key to be cached in one of the keyrings. +calling KEYCTL_INSTANTIATE or KEYCTL_INSTANTIATE_IOV, which also permits it to +cache the key in one of the keyrings (probably the session ring) before +returning. Alternatively, the key can be marked as negative with KEYCTL_NEGATE +or KEYCTL_REJECT; this also permits the key to be cached in one of the +keyrings. If it returns with the key remaining in the unconstructed state, the key will be marked as being negative, it will be added to the session keyring, and an diff --git a/arch/x86/Kconfig b/arch/x86/Kconfig index d5ed94d30aa..b46b75bef49 100644 --- a/arch/x86/Kconfig +++ b/arch/x86/Kconfig @@ -2138,6 +2138,11 @@ config SYSVIPC_COMPAT def_bool y depends on COMPAT && SYSVIPC +config KEYS_COMPAT + bool + depends on COMPAT && KEYS + default y + endmenu diff --git a/include/linux/keyctl.h b/include/linux/keyctl.h index 7022974def0..9b0b865ce62 100644 --- a/include/linux/keyctl.h +++ b/include/linux/keyctl.h @@ -54,5 +54,6 @@ #define KEYCTL_GET_SECURITY 17 /* get key security label */ #define KEYCTL_SESSION_TO_PARENT 18 /* apply session keyring to parent process */ #define KEYCTL_REJECT 19 /* reject a partially constructed key */ +#define KEYCTL_INSTANTIATE_IOV 20 /* instantiate a partially constructed key */ #endif /* _LINUX_KEYCTL_H */ diff --git a/security/keys/compat.c b/security/keys/compat.c index 17c99d0149e..338b510e902 100644 --- a/security/keys/compat.c +++ b/security/keys/compat.c @@ -12,9 +12,52 @@ #include <linux/syscalls.h> #include <linux/keyctl.h> #include <linux/compat.h> +#include <linux/slab.h> #include "internal.h" /* + * Instantiate a key with the specified compatibility multipart payload and + * link the key into the destination keyring if one is given. + * + * The caller must have the appropriate instantiation permit set for this to + * work (see keyctl_assume_authority). No other permissions are required. + * + * If successful, 0 will be returned. + */ +long compat_keyctl_instantiate_key_iov( + key_serial_t id, + const struct compat_iovec __user *_payload_iov, + unsigned ioc, + key_serial_t ringid) +{ + struct iovec iovstack[UIO_FASTIOV], *iov = iovstack; + long ret; + + if (_payload_iov == 0 || ioc == 0) + goto no_payload; + + ret = compat_rw_copy_check_uvector(WRITE, _payload_iov, ioc, + ARRAY_SIZE(iovstack), + iovstack, &iov); + if (ret < 0) + return ret; + if (ret == 0) + goto no_payload_free; + + ret = keyctl_instantiate_key_common(id, iov, ioc, ret, ringid); + + if (iov != iovstack) + kfree(iov); + return ret; + +no_payload_free: + if (iov != iovstack) + kfree(iov); +no_payload: + return keyctl_instantiate_key_common(id, NULL, 0, 0, ringid); +} + +/* * The key control system call, 32-bit compatibility version for 64-bit archs * * This should only be called if the 64-bit arch uses weird pointers in 32-bit @@ -88,6 +131,10 @@ asmlinkage long compat_sys_keyctl(u32 option, case KEYCTL_REJECT: return keyctl_reject_key(arg2, arg3, arg4, arg5); + case KEYCTL_INSTANTIATE_IOV: + return compat_keyctl_instantiate_key_iov( + arg2, compat_ptr(arg3), arg4, arg5); + default: return -EOPNOTSUPP; } diff --git a/security/keys/internal.h b/security/keys/internal.h index 286c0959ee5..07a025f8190 100644 --- a/security/keys/internal.h +++ b/security/keys/internal.h @@ -215,6 +215,13 @@ extern long keyctl_get_security(key_serial_t keyid, char __user *buffer, size_t buflen); extern long keyctl_session_to_parent(void); extern long keyctl_reject_key(key_serial_t, unsigned, unsigned, key_serial_t); +extern long keyctl_instantiate_key_iov(key_serial_t, + const struct iovec __user *, + unsigned, key_serial_t); + +extern long keyctl_instantiate_key_common(key_serial_t, + const struct iovec __user *, + unsigned, size_t, key_serial_t); /* * Debugging key validation diff --git a/security/keys/keyctl.c b/security/keys/keyctl.c index 0d7b1946ff9..427fddcaeb1 100644 --- a/security/keys/keyctl.c +++ b/security/keys/keyctl.c @@ -913,6 +913,21 @@ static int keyctl_change_reqkey_auth(struct key *key) } /* + * Copy the iovec data from userspace + */ +static long copy_from_user_iovec(void *buffer, const struct iovec *iov, + unsigned ioc) +{ + for (; ioc > 0; ioc--) { + if (copy_from_user(buffer, iov->iov_base, iov->iov_len) != 0) + return -EFAULT; + buffer += iov->iov_len; + iov++; + } + return 0; +} + +/* * Instantiate a key with the specified payload and link the key into the * destination keyring if one is given. * @@ -921,10 +936,11 @@ static int keyctl_change_reqkey_auth(struct key *key) * * If successful, 0 will be returned. */ -long keyctl_instantiate_key(key_serial_t id, - const void __user *_payload, - size_t plen, - key_serial_t ringid) +long keyctl_instantiate_key_common(key_serial_t id, + const struct iovec *payload_iov, + unsigned ioc, + size_t plen, + key_serial_t ringid) { const struct cred *cred = current_cred(); struct request_key_auth *rka; @@ -953,7 +969,7 @@ long keyctl_instantiate_key(key_serial_t id, /* pull the payload in if one was supplied */ payload = NULL; - if (_payload) { + if (payload_iov) { ret = -ENOMEM; payload = kmalloc(plen, GFP_KERNEL); if (!payload) { @@ -965,8 +981,8 @@ long keyctl_instantiate_key(key_serial_t id, goto error; } - ret = -EFAULT; - if (copy_from_user(payload, _payload, plen) != 0) + ret = copy_from_user_iovec(payload, payload_iov, ioc); + if (ret < 0) goto error2; } @@ -997,6 +1013,72 @@ error: } /* + * Instantiate a key with the specified payload and link the key into the + * destination keyring if one is given. + * + * The caller must have the appropriate instantiation permit set for this to + * work (see keyctl_assume_authority). No other permissions are required. + * + * If successful, 0 will be returned. + */ +long keyctl_instantiate_key(key_serial_t id, + const void __user *_payload, + size_t plen, + key_serial_t ringid) +{ + if (_payload && plen) { + struct iovec iov[1] = { + [0].iov_base = (void __user *)_payload, + [0].iov_len = plen + }; + + return keyctl_instantiate_key_common(id, iov, 1, plen, ringid); + } + + return keyctl_instantiate_key_common(id, NULL, 0, 0, ringid); +} + +/* + * Instantiate a key with the specified multipart payload and link the key into + * the destination keyring if one is given. + * + * The caller must have the appropriate instantiation permit set for this to + * work (see keyctl_assume_authority). No other permissions are required. + * + * If successful, 0 will be returned. + */ +long keyctl_instantiate_key_iov(key_serial_t id, + const struct iovec __user *_payload_iov, + unsigned ioc, + key_serial_t ringid) +{ + struct iovec iovstack[UIO_FASTIOV], *iov = iovstack; + long ret; + + if (_payload_iov == 0 || ioc == 0) + goto no_payload; + + ret = rw_copy_check_uvector(WRITE, _payload_iov, ioc, + ARRAY_SIZE(iovstack), iovstack, &iov); + if (ret < 0) + return ret; + if (ret == 0) + goto no_payload_free; + + ret = keyctl_instantiate_key_common(id, iov, ioc, ret, ringid); + + if (iov != iovstack) + kfree(iov); + return ret; + +no_payload_free: + if (iov != iovstack) + kfree(iov); +no_payload: + return keyctl_instantiate_key_common(id, NULL, 0, 0, ringid); +} + +/* * Negatively instantiate the key with the given timeout (in seconds) and link * the key into the destination keyring if one is given. * @@ -1528,6 +1610,13 @@ SYSCALL_DEFINE5(keyctl, int, option, unsigned long, arg2, unsigned long, arg3, (unsigned) arg4, (key_serial_t) arg5); + case KEYCTL_INSTANTIATE_IOV: + return keyctl_instantiate_key_iov( + (key_serial_t) arg2, + (const struct iovec __user *) arg3, + (unsigned) arg4, + (key_serial_t) arg5); + default: return -EOPNOTSUPP; } |