| Message ID | 20170505142152.29795-5-roberto.sassu@huawei.com |
|---|---|
| State | New |
| Headers | show |
On Fri, 2017-05-05 at 16:21 +0200, Roberto Sassu wrote: > pcrlock() has been modified to pass the correct arguments > to tpm_pcr_extend(): the pointer of a tpm2_digest structure containing > a random value generated by tpm_get_random() and the size of the array (1). If the number of arguments is wrong, that means the patch that introduced the change is not bi-sect safe. (This comment is applicable to patch 5/5 too.) Mimi > Signed-off-by: Roberto Sassu <roberto.sassu@huawei.com> > --- > security/keys/trusted.c | 6 +++--- > 1 file changed, 3 insertions(+), 3 deletions(-) > > diff --git a/security/keys/trusted.c b/security/keys/trusted.c > index 2ae31c5..3eb89e6 100644 > --- a/security/keys/trusted.c > +++ b/security/keys/trusted.c > @@ -377,15 +377,15 @@ static int trusted_tpm_send(const u32 chip_num, unsigned char *cmd, > */ > static int pcrlock(const int pcrnum) > { > - unsigned char hash[SHA1_DIGEST_SIZE]; > + struct tpm2_digest digestarg = {.alg_id = TPM2_ALG_SHA1}; > int ret; > > if (!capable(CAP_SYS_ADMIN)) > return -EPERM; > - ret = tpm_get_random(TPM_ANY_NUM, hash, SHA1_DIGEST_SIZE); > + ret = tpm_get_random(TPM_ANY_NUM, digestarg.digest, SHA1_DIGEST_SIZE); > if (ret != SHA1_DIGEST_SIZE) > return ret; > - return tpm_pcr_extend(TPM_ANY_NUM, pcrnum, hash) ? -EINVAL : 0; > + return tpm_pcr_extend(TPM_ANY_NUM, pcrnum, 1, &digestarg) ? -EINVAL : 0; > } > > /* ------------------------------------------------------------------------------ Check out the vibrant tech community on one of the world's most engaging tech sites, Slashdot.org! http://sdm.link/slashdot
On 5/30/2017 5:35 AM, Mimi Zohar wrote: > On Fri, 2017-05-05 at 16:21 +0200, Roberto Sassu wrote: >> pcrlock() has been modified to pass the correct arguments >> to tpm_pcr_extend(): the pointer of a tpm2_digest structure containing >> a random value generated by tpm_get_random() and the size of the array (1). > > If the number of arguments is wrong, that means the patch that > introduced the change is not bi-sect safe. (This comment is > applicable to patch 5/5 too.) Jarkko (the TPM driver maintainer) asked me to not introduce a new function to pass multiple digests, but to modify the parameters of tpm_pcr_extend(). Roberto > > Mimi > >> Signed-off-by: Roberto Sassu <roberto.sassu@huawei.com> >> --- >> security/keys/trusted.c | 6 +++--- >> 1 file changed, 3 insertions(+), 3 deletions(-) >> >> diff --git a/security/keys/trusted.c b/security/keys/trusted.c >> index 2ae31c5..3eb89e6 100644 >> --- a/security/keys/trusted.c >> +++ b/security/keys/trusted.c >> @@ -377,15 +377,15 @@ static int trusted_tpm_send(const u32 chip_num, unsigned char *cmd, >> */ >> static int pcrlock(const int pcrnum) >> { >> - unsigned char hash[SHA1_DIGEST_SIZE]; >> + struct tpm2_digest digestarg = {.alg_id = TPM2_ALG_SHA1}; >> int ret; >> >> if (!capable(CAP_SYS_ADMIN)) >> return -EPERM; >> - ret = tpm_get_random(TPM_ANY_NUM, hash, SHA1_DIGEST_SIZE); >> + ret = tpm_get_random(TPM_ANY_NUM, digestarg.digest, SHA1_DIGEST_SIZE); >> if (ret != SHA1_DIGEST_SIZE) >> return ret; >> - return tpm_pcr_extend(TPM_ANY_NUM, pcrnum, hash) ? -EINVAL : 0; >> + return tpm_pcr_extend(TPM_ANY_NUM, pcrnum, 1, &digestarg) ? -EINVAL : 0; >> } >> >> /* > ------------------------------------------------------------------------------ Check out the vibrant tech community on one of the world's most engaging tech sites, Slashdot.org! http://sdm.link/slashdot
On Tue, 2017-05-30 at 09:36 +0200, Roberto Sassu wrote: > On 5/30/2017 5:35 AM, Mimi Zohar wrote: > > On Fri, 2017-05-05 at 16:21 +0200, Roberto Sassu wrote: > >> pcrlock() has been modified to pass the correct arguments > >> to tpm_pcr_extend(): the pointer of a tpm2_digest structure containing > >> a random value generated by tpm_get_random() and the size of the array (1). > > > > If the number of arguments is wrong, that means the patch that > > introduced the change is not bi-sect safe. (This comment is > > applicable to patch 5/5 too.) > > Jarkko (the TPM driver maintainer) asked me to not introduce > a new function to pass multiple digests, but to modify > the parameters of tpm_pcr_extend(). Since struct tpm2_digest is a static size, shouldn't we be able to compute the number of digests? Mimi ------------------------------------------------------------------------------ Check out the vibrant tech community on one of the world's most engaging tech sites, Slashdot.org! http://sdm.link/slashdot
On 5/30/2017 2:06 PM, Mimi Zohar wrote: > On Tue, 2017-05-30 at 09:36 +0200, Roberto Sassu wrote: >> On 5/30/2017 5:35 AM, Mimi Zohar wrote: >>> On Fri, 2017-05-05 at 16:21 +0200, Roberto Sassu wrote: >>>> pcrlock() has been modified to pass the correct arguments >>>> to tpm_pcr_extend(): the pointer of a tpm2_digest structure containing >>>> a random value generated by tpm_get_random() and the size of the array (1). >>> >>> If the number of arguments is wrong, that means the patch that >>> introduced the change is not bi-sect safe. (This comment is >>> applicable to patch 5/5 too.) >> >> Jarkko (the TPM driver maintainer) asked me to not introduce >> a new function to pass multiple digests, but to modify >> the parameters of tpm_pcr_extend(). > > Since struct tpm2_digest is a static size, shouldn't we be able to > compute the number of digests? The length of 'hash' is not passed to tpm_pcr_extend(). The only way to avoid changing the number of parameters would be to pass a buffer whose format is the same of the event log format defined by TCG: <algo count> <algo1 ID> <digest1> ... <algoN ID> <digestN> Roberto
diff --git a/security/keys/trusted.c b/security/keys/trusted.c index 2ae31c5..3eb89e6 100644 --- a/security/keys/trusted.c +++ b/security/keys/trusted.c @@ -377,15 +377,15 @@ static int trusted_tpm_send(const u32 chip_num, unsigned char *cmd, */ static int pcrlock(const int pcrnum) { - unsigned char hash[SHA1_DIGEST_SIZE]; + struct tpm2_digest digestarg = {.alg_id = TPM2_ALG_SHA1}; int ret; if (!capable(CAP_SYS_ADMIN)) return -EPERM; - ret = tpm_get_random(TPM_ANY_NUM, hash, SHA1_DIGEST_SIZE); + ret = tpm_get_random(TPM_ANY_NUM, digestarg.digest, SHA1_DIGEST_SIZE); if (ret != SHA1_DIGEST_SIZE) return ret; - return tpm_pcr_extend(TPM_ANY_NUM, pcrnum, hash) ? -EINVAL : 0; + return tpm_pcr_extend(TPM_ANY_NUM, pcrnum, 1, &digestarg) ? -EINVAL : 0; } /*
pcrlock() has been modified to pass the correct arguments to tpm_pcr_extend(): the pointer of a tpm2_digest structure containing a random value generated by tpm_get_random() and the size of the array (1). Signed-off-by: Roberto Sassu <roberto.sassu@huawei.com> --- security/keys/trusted.c | 6 +++--- 1 file changed, 3 insertions(+), 3 deletions(-)