On Fri, 2018-03-16 at 17:38 -0300, Thiago Jung Bauermann wrote:
> IMA will need to obtain the keyring used to verify file signatures so that
> it can verify the module-style signature appended to files.
>
> Signed-off-by: Thiago Jung Bauermann <bauerman@xxxxxxxxxxxxxxxxxx>
Signed-off-by: Mimi Zohar <zohar@xxxxxxxxxxxxxxxxxx>
> ---
> security/integrity/digsig.c | 28 +++++++++++++++++++++-------
> security/integrity/integrity.h | 6 ++++++
> 2 files changed, 27 insertions(+), 7 deletions(-)
>
> diff --git a/security/integrity/digsig.c b/security/integrity/digsig.c
> index 6f9e4ce568cd..e641a67b9fc7 100644
> --- a/security/integrity/digsig.c
> +++ b/security/integrity/digsig.c
> @@ -48,11 +48,10 @@ static bool init_keyring __initdata;
> #define restrict_link_to_ima restrict_link_by_builtin_trusted
> #endif
>
> -int integrity_digsig_verify(const unsigned int id, const char *sig, int siglen,
> - const char *digest, int digestlen)
> +struct key *integrity_keyring_from_id(const unsigned int id)
> {
> - if (id >= INTEGRITY_KEYRING_MAX || siglen < 2)
> - return -EINVAL;
> + if (id >= INTEGRITY_KEYRING_MAX)
> + return ERR_PTR(-EINVAL);
>
> if (!keyring[id]) {
> keyring[id] =
> @@ -61,17 +60,32 @@ int integrity_digsig_verify(const unsigned int id, const char *sig, int siglen,
> int err = PTR_ERR(keyring[id]);
> pr_err("no %s keyring: %d\n", keyring_name[id], err);
> keyring[id] = NULL;
> - return err;
> + return ERR_PTR(err);
> }
> }
>
> + return keyring[id];
> +}
> +
> +int integrity_digsig_verify(const unsigned int id, const char *sig, int siglen,
> + const char *digest, int digestlen)
> +{
> + struct key *keyring;
> +
> + if (siglen < 2)
> + return -EINVAL;
> +
> + keyring = integrity_keyring_from_id(id);
> + if (IS_ERR(keyring))
> + return PTR_ERR(keyring);
> +
> switch (sig[1]) {
> case 1:
> /* v1 API expect signature without xattr type */
> - return digsig_verify(keyring[id], sig + 1, siglen - 1,
> + return digsig_verify(keyring, sig + 1, siglen - 1,
> digest, digestlen);
> case 2:
> - return asymmetric_verify(keyring[id], sig, siglen,
> + return asymmetric_verify(keyring, sig, siglen,
> digest, digestlen);
> }
>
> diff --git a/security/integrity/integrity.h b/security/integrity/integrity.h
> index 79799a0d9195..2d245f44ca26 100644
> --- a/security/integrity/integrity.h
> +++ b/security/integrity/integrity.h
> @@ -150,6 +150,7 @@ int integrity_kernel_read(struct file *file, loff_t offset,
>
> #ifdef CONFIG_INTEGRITY_SIGNATURE
>
> +struct key *integrity_keyring_from_id(const unsigned int id);
> int integrity_digsig_verify(const unsigned int id, const char *sig, int siglen,
> const char *digest, int digestlen);
>
> @@ -157,6 +158,11 @@ int __init integrity_init_keyring(const unsigned int id);
> int __init integrity_load_x509(const unsigned int id, const char *path);
> #else
>
> +static inline struct key *integrity_keyring_from_id(const unsigned int id)
> +{
> + return ERR_PTR(-EINVAL);
> +}
> +
> static inline int integrity_digsig_verify(const unsigned int id,
> const char *sig, int siglen,
> const char *digest, int digestlen)
>
