Re: [PATCH 3/3] crypto: hwrng add sysfs attribute to show user selected rng
Hi Harald, > Hello PrasannaKumar > > here is now a version which combines patch 2 and patch 3 together > according to your suggestions: > > == cut == > > From: Harald Freudenberger > Date: Fri, 30 Jun 2017 17:06:40 +0200 > Subject: [PATCH 2/2] crypto: hwrng remember rng chosen by user > > When a user chooses a rng source via sysfs attribute > this rng should be sticky, even when other sources > with better quality to register. This patch introduces > a simple way to remember the user's choice. This is > reflected by a new sysfs attribute file 'rng_selected' > which shows if the current rng has been chosen by > userspace. The new attribute file shows '1' for user > selected rng and '0' otherwise. > > Signed-off-by: Harald Freudenberger > --- > drivers/char/hw_random/core.c | 21 +++-- > 1 file changed, 19 insertions(+), 2 deletions(-) > > diff --git a/drivers/char/hw_random/core.c b/drivers/char/hw_random/core.c > index e9dda16..9701ac7 100644 > --- a/drivers/char/hw_random/core.c > +++ b/drivers/char/hw_random/core.c > @@ -28,6 +28,8 @@ > #define RNG_MODULE_NAME"hw_random" > > static struct hwrng *current_rng; > +/* the current rng has been explicitly chosen by user via sysfs */ > +static int cur_rng_set_by_user; > static struct task_struct *hwrng_fill; > /* list of registered rngs, sorted decending by quality */ > static LIST_HEAD(rng_list); > @@ -304,6 +306,7 @@ static ssize_t hwrng_attr_current_store(struct device > *dev, > list_for_each_entry(rng, &rng_list, list) { > if (sysfs_streq(rng->name, buf)) { > err = 0; > +cur_rng_set_by_user = 1; > if (rng != current_rng) > err = set_current_rng(rng); > break; > @@ -352,16 +355,27 @@ static ssize_t hwrng_attr_available_show(struct device > *dev, > return strlen(buf); > } > > +static ssize_t hwrng_attr_selected_show(struct device *dev, > +struct device_attribute *attr, > +char *buf) > +{ > +return snprintf(buf, PAGE_SIZE, "%d\n", cur_rng_set_by_user); > +} > + > static DEVICE_ATTR(rng_current, S_IRUGO | S_IWUSR, > hwrng_attr_current_show, > hwrng_attr_current_store); > static DEVICE_ATTR(rng_available, S_IRUGO, > hwrng_attr_available_show, > NULL); > +static DEVICE_ATTR(rng_selected, S_IRUGO, > + hwrng_attr_selected_show, > + NULL); > > static struct attribute *rng_dev_attrs[] = { > &dev_attr_rng_current.attr, > &dev_attr_rng_available.attr, > +&dev_attr_rng_selected.attr, > NULL > }; > > @@ -444,10 +458,12 @@ int hwrng_register(struct hwrng *rng) > > old_rng = current_rng; > err = 0; > -if (!old_rng || (rng->quality > old_rng->quality)) { > +if (!old_rng || > +(!cur_rng_set_by_user && rng->quality > old_rng->quality)) { > /* > * Set new rng as current as the new rng source > - * provides better entropy quality. > + * provides better entropy quality and was not > + * chosen by userspace. > */ > err = set_current_rng(rng); > if (err) > @@ -479,6 +495,7 @@ void hwrng_unregister(struct hwrng *rng) > list_del(&rng->list); > if (current_rng == rng) { > drop_current_rng(); > +cur_rng_set_by_user = 0; > /* rng_list is sorted by quality, use the best (=first) one */ > if (!list_empty(&rng_list)) { > struct hwrng *new_rng; > -- > 2.7.4 > > == cut == > Good work, patch looks good to me. Reviewed-by: PrasannaKumar Muralidharan . I am wondering if you want to make a v2 of the whole series. You can just put your patch 1 and 2 and send it again with description. Requiring a v2 depends on how Herbert prefers to take patches in. Herbert, Do you prefer a v2 of the patch series or you can take this version of patch 2? Note: If you are re-posting this patch as v2 please add my reviewed by tag for both the patches. Regards, PrasannaKumar
Re: [PATCH 3/3] crypto: hwrng add sysfs attribute to show user selected rng
On 07/06/2017 06:51 AM, PrasannaKumar Muralidharan wrote: > Hi Harald, > >> Here is an updated version with just showing 0 or 1 in the new sysfs >> attribute file: >> == cut == >> From: Harald Freudenberger >> Date: Mon, 3 Jul 2017 10:19:22 +0200 >> Subject: [PATCH 3/3] crypto: hwrng add sysfs attribute to show user selected >> rng >> >> This patch introduces a new sysfs attribute file 'rng_selected' >> which shows if the current rng has been chosen by userspace. ... > Nice to see quick turn around time. Why not just use the > cur_rng_set_by_user instead of selected_rng? This way patch 3 won't > change things that patch 2 introduced and patch 3 will become much > smaller. Also I feel folding patch 3 and 2 will make sense as both are > related to user selected rng. > > Regards, > PrasannaKumar > Hello PrasannaKumar here is now a version which combines patch 2 and patch 3 together according to your suggestions: == cut == From: Harald Freudenberger Date: Fri, 30 Jun 2017 17:06:40 +0200 Subject: [PATCH 2/2] crypto: hwrng remember rng chosen by user When a user chooses a rng source via sysfs attribute this rng should be sticky, even when other sources with better quality to register. This patch introduces a simple way to remember the user's choice. This is reflected by a new sysfs attribute file 'rng_selected' which shows if the current rng has been chosen by userspace. The new attribute file shows '1' for user selected rng and '0' otherwise. Signed-off-by: Harald Freudenberger --- drivers/char/hw_random/core.c | 21 +++-- 1 file changed, 19 insertions(+), 2 deletions(-) diff --git a/drivers/char/hw_random/core.c b/drivers/char/hw_random/core.c index e9dda16..9701ac7 100644 --- a/drivers/char/hw_random/core.c +++ b/drivers/char/hw_random/core.c @@ -28,6 +28,8 @@ #define RNG_MODULE_NAME"hw_random" static struct hwrng *current_rng; +/* the current rng has been explicitly chosen by user via sysfs */ +static int cur_rng_set_by_user; static struct task_struct *hwrng_fill; /* list of registered rngs, sorted decending by quality */ static LIST_HEAD(rng_list); @@ -304,6 +306,7 @@ static ssize_t hwrng_attr_current_store(struct device *dev, list_for_each_entry(rng, &rng_list, list) { if (sysfs_streq(rng->name, buf)) { err = 0; +cur_rng_set_by_user = 1; if (rng != current_rng) err = set_current_rng(rng); break; @@ -352,16 +355,27 @@ static ssize_t hwrng_attr_available_show(struct device *dev, return strlen(buf); } +static ssize_t hwrng_attr_selected_show(struct device *dev, +struct device_attribute *attr, +char *buf) +{ +return snprintf(buf, PAGE_SIZE, "%d\n", cur_rng_set_by_user); +} + static DEVICE_ATTR(rng_current, S_IRUGO | S_IWUSR, hwrng_attr_current_show, hwrng_attr_current_store); static DEVICE_ATTR(rng_available, S_IRUGO, hwrng_attr_available_show, NULL); +static DEVICE_ATTR(rng_selected, S_IRUGO, + hwrng_attr_selected_show, + NULL); static struct attribute *rng_dev_attrs[] = { &dev_attr_rng_current.attr, &dev_attr_rng_available.attr, +&dev_attr_rng_selected.attr, NULL }; @@ -444,10 +458,12 @@ int hwrng_register(struct hwrng *rng) old_rng = current_rng; err = 0; -if (!old_rng || (rng->quality > old_rng->quality)) { +if (!old_rng || +(!cur_rng_set_by_user && rng->quality > old_rng->quality)) { /* * Set new rng as current as the new rng source - * provides better entropy quality. + * provides better entropy quality and was not + * chosen by userspace. */ err = set_current_rng(rng); if (err) @@ -479,6 +495,7 @@ void hwrng_unregister(struct hwrng *rng) list_del(&rng->list); if (current_rng == rng) { drop_current_rng(); +cur_rng_set_by_user = 0; /* rng_list is sorted by quality, use the best (=first) one */ if (!list_empty(&rng_list)) { struct hwrng *new_rng; -- 2.7.4 == cut ==
Re: [PATCH 3/3] crypto: hwrng add sysfs attribute to show user selected rng
Hi Harald, > Here is an updated version with just showing 0 or 1 in the new sysfs > attribute file: > == cut == > From: Harald Freudenberger > Date: Mon, 3 Jul 2017 10:19:22 +0200 > Subject: [PATCH 3/3] crypto: hwrng add sysfs attribute to show user selected > rng > > This patch introduces a new sysfs attribute file 'rng_selected' > which shows if the current rng has been chosen by userspace. > > If a rng source is chosen by user via echo some valid string > to rng_current there should be a way to signal this choice to > userspace. The new attribute file 'rng_selected' shows '1' for > user selecte rng and '0' otherwise. > > Signed-off-by: Harald Freudenberger > --- > drivers/char/hw_random/core.c | 21 - > 1 file changed, 16 insertions(+), 5 deletions(-) > > diff --git a/drivers/char/hw_random/core.c b/drivers/char/hw_random/core.c > index ffd4e36..2b4c7f6 100644 > --- a/drivers/char/hw_random/core.c > +++ b/drivers/char/hw_random/core.c > @@ -28,8 +28,8 @@ > #define RNG_MODULE_NAME"hw_random" > > static struct hwrng *current_rng; > -/* the current rng has been explicitly chosen by user via sysfs */ > -static int cur_rng_set_by_user; > +/* the rng explicitly selected by user via sysfs */ > +static struct hwrng *selected_rng; > static struct task_struct *hwrng_fill; > /* list of registered rngs, sorted decending by quality */ > static LIST_HEAD(rng_list); > @@ -306,7 +306,7 @@ static ssize_t hwrng_attr_current_store(struct device > *dev, > list_for_each_entry(rng, &rng_list, list) { > if (sysfs_streq(rng->name, buf)) { > err = 0; > -cur_rng_set_by_user = 1; > +selected_rng = rng; > if (rng != current_rng) > err = set_current_rng(rng); > break; > @@ -355,16 +355,27 @@ static ssize_t hwrng_attr_available_show(struct device > *dev, > return strlen(buf); > } > > +static ssize_t hwrng_attr_selected_show(struct device *dev, > +struct device_attribute *attr, > +char *buf) > +{ > +return snprintf(buf, PAGE_SIZE, "%d\n", selected_rng ? 1 : 0); > +} > + > static DEVICE_ATTR(rng_current, S_IRUGO | S_IWUSR, > hwrng_attr_current_show, > hwrng_attr_current_store); > static DEVICE_ATTR(rng_available, S_IRUGO, > hwrng_attr_available_show, > NULL); > +static DEVICE_ATTR(rng_selected, S_IRUGO, > + hwrng_attr_selected_show, > + NULL); > > static struct attribute *rng_dev_attrs[] = { > &dev_attr_rng_current.attr, > &dev_attr_rng_available.attr, > +&dev_attr_rng_selected.attr, > NULL > }; > > @@ -448,7 +459,7 @@ int hwrng_register(struct hwrng *rng) > old_rng = current_rng; > err = 0; > if (!old_rng || > -(!cur_rng_set_by_user && rng->quality > old_rng->quality)) { > +(!selected_rng && rng->quality > old_rng->quality)) { > /* > * Set new rng as current as the new rng source > * provides better entropy quality and was not > @@ -484,7 +495,7 @@ void hwrng_unregister(struct hwrng *rng) > list_del(&rng->list); > if (current_rng == rng) { > drop_current_rng(); > -cur_rng_set_by_user = 0; > +selected_rng = NULL; > /* rng_list is sorted by quality, use the best (=first) one */ > if (!list_empty(&rng_list)) { > struct hwrng *new_rng; > -- > 2.7.4 > == cut == > Nice to see quick turn around time. Why not just use the cur_rng_set_by_user instead of selected_rng? This way patch 3 won't change things that patch 2 introduced and patch 3 will become much smaller. Also I feel folding patch 3 and 2 will make sense as both are related to user selected rng. Regards, PrasannaKumar
Re: [PATCH 3/3] crypto: hwrng add sysfs attribute to show user selected rng
On 07/04/2017 03:15 PM, PrasannaKumar Muralidharan wrote: > On 3 July 2017 at 15:33, Harald Freudenberger > wrote: >> This patch introduces a new sysfs attribute file 'rng_selected' >> which shows the the rng chosen by userspace. >> >> If a rng source is chosen by user via echo some valid string >> to rng_current there should be a way to signal this choice to >> userspace. The new attribute file 'rng_selected' shows either >> the name of the rng chosen or 'none'. >> >> Signed-off-by: Harald Freudenberger >> --- >> drivers/char/hw_random/core.c | 22 +- >> 1 file changed, 17 insertions(+), 5 deletions(-) >> >> diff --git a/drivers/char/hw_random/core.c b/drivers/char/hw_random/core.c >> index ffd4e36..6a6276a 100644 >> --- a/drivers/char/hw_random/core.c >> +++ b/drivers/char/hw_random/core.c >> @@ -28,8 +28,8 @@ >> #define RNG_MODULE_NAME"hw_random" >> >> static struct hwrng *current_rng; >> -/* the current rng has been explicitly chosen by user via sysfs */ >> -static int cur_rng_set_by_user; >> +/* the rng explicitly selected by user via sysfs */ >> +static struct hwrng *selected_rng; >> static struct task_struct *hwrng_fill; >> /* list of registered rngs, sorted decending by quality */ >> static LIST_HEAD(rng_list); >> @@ -306,7 +306,7 @@ static ssize_t hwrng_attr_current_store(struct device >> *dev, >> list_for_each_entry(rng, &rng_list, list) { >> if (sysfs_streq(rng->name, buf)) { >> err = 0; >> - cur_rng_set_by_user = 1; >> + selected_rng = rng; >> if (rng != current_rng) >> err = set_current_rng(rng); >> break; >> @@ -355,16 +355,28 @@ static ssize_t hwrng_attr_available_show(struct device >> *dev, >> return strlen(buf); >> } >> >> +static ssize_t hwrng_attr_selected_show(struct device *dev, >> + struct device_attribute *attr, >> + char *buf) >> +{ >> + return snprintf(buf, PAGE_SIZE, "%s\n", >> + selected_rng ? selected_rng->name : "none"); >> +} >> + >> static DEVICE_ATTR(rng_current, S_IRUGO | S_IWUSR, >>hwrng_attr_current_show, >>hwrng_attr_current_store); >> static DEVICE_ATTR(rng_available, S_IRUGO, >>hwrng_attr_available_show, >>NULL); >> +static DEVICE_ATTR(rng_selected, S_IRUGO, >> + hwrng_attr_selected_show, >> + NULL); >> >> static struct attribute *rng_dev_attrs[] = { >> &dev_attr_rng_current.attr, >> &dev_attr_rng_available.attr, >> + &dev_attr_rng_selected.attr, >> NULL >> }; >> >> @@ -448,7 +460,7 @@ int hwrng_register(struct hwrng *rng) >> old_rng = current_rng; >> err = 0; >> if (!old_rng || >> - (!cur_rng_set_by_user && rng->quality > old_rng->quality)) { >> + (!selected_rng && rng->quality > old_rng->quality)) { >> /* >> * Set new rng as current as the new rng source >> * provides better entropy quality and was not >> @@ -484,7 +496,7 @@ void hwrng_unregister(struct hwrng *rng) >> list_del(&rng->list); >> if (current_rng == rng) { >> drop_current_rng(); >> - cur_rng_set_by_user = 0; >> + selected_rng = NULL; >> /* rng_list is sorted by quality, use the best (=first) one >> */ >> if (!list_empty(&rng_list)) { >> struct hwrng *new_rng; >> -- >> 2.7.4 >> > The current_rng sysfs attribute shows currently selected rng. So this > new attribute can contain 1 to indicate user's choice, 0 otherwise. > > Regards, > PrasannaKumar > Here is an updated version with just showing 0 or 1 in the new sysfs attribute file: == cut == From: Harald Freudenberger Date: Mon, 3 Jul 2017 10:19:22 +0200 Subject: [PATCH 3/3] crypto: hwrng add sysfs attribute to show user selected rng This patch introduces a new sysfs attribute file 'rng_selected' which shows if the current rng has been chosen by userspace. If a rn
Re: [PATCH 3/3] crypto: hwrng add sysfs attribute to show user selected rng
On 3 July 2017 at 15:33, Harald Freudenberger wrote: > This patch introduces a new sysfs attribute file 'rng_selected' > which shows the the rng chosen by userspace. > > If a rng source is chosen by user via echo some valid string > to rng_current there should be a way to signal this choice to > userspace. The new attribute file 'rng_selected' shows either > the name of the rng chosen or 'none'. > > Signed-off-by: Harald Freudenberger > --- > drivers/char/hw_random/core.c | 22 +- > 1 file changed, 17 insertions(+), 5 deletions(-) > > diff --git a/drivers/char/hw_random/core.c b/drivers/char/hw_random/core.c > index ffd4e36..6a6276a 100644 > --- a/drivers/char/hw_random/core.c > +++ b/drivers/char/hw_random/core.c > @@ -28,8 +28,8 @@ > #define RNG_MODULE_NAME"hw_random" > > static struct hwrng *current_rng; > -/* the current rng has been explicitly chosen by user via sysfs */ > -static int cur_rng_set_by_user; > +/* the rng explicitly selected by user via sysfs */ > +static struct hwrng *selected_rng; > static struct task_struct *hwrng_fill; > /* list of registered rngs, sorted decending by quality */ > static LIST_HEAD(rng_list); > @@ -306,7 +306,7 @@ static ssize_t hwrng_attr_current_store(struct device > *dev, > list_for_each_entry(rng, &rng_list, list) { > if (sysfs_streq(rng->name, buf)) { > err = 0; > - cur_rng_set_by_user = 1; > + selected_rng = rng; > if (rng != current_rng) > err = set_current_rng(rng); > break; > @@ -355,16 +355,28 @@ static ssize_t hwrng_attr_available_show(struct device > *dev, > return strlen(buf); > } > > +static ssize_t hwrng_attr_selected_show(struct device *dev, > + struct device_attribute *attr, > + char *buf) > +{ > + return snprintf(buf, PAGE_SIZE, "%s\n", > + selected_rng ? selected_rng->name : "none"); > +} > + > static DEVICE_ATTR(rng_current, S_IRUGO | S_IWUSR, >hwrng_attr_current_show, >hwrng_attr_current_store); > static DEVICE_ATTR(rng_available, S_IRUGO, >hwrng_attr_available_show, >NULL); > +static DEVICE_ATTR(rng_selected, S_IRUGO, > + hwrng_attr_selected_show, > + NULL); > > static struct attribute *rng_dev_attrs[] = { > &dev_attr_rng_current.attr, > &dev_attr_rng_available.attr, > + &dev_attr_rng_selected.attr, > NULL > }; > > @@ -448,7 +460,7 @@ int hwrng_register(struct hwrng *rng) > old_rng = current_rng; > err = 0; > if (!old_rng || > - (!cur_rng_set_by_user && rng->quality > old_rng->quality)) { > + (!selected_rng && rng->quality > old_rng->quality)) { > /* > * Set new rng as current as the new rng source > * provides better entropy quality and was not > @@ -484,7 +496,7 @@ void hwrng_unregister(struct hwrng *rng) > list_del(&rng->list); > if (current_rng == rng) { > drop_current_rng(); > - cur_rng_set_by_user = 0; > + selected_rng = NULL; > /* rng_list is sorted by quality, use the best (=first) one */ > if (!list_empty(&rng_list)) { > struct hwrng *new_rng; > -- > 2.7.4 > The current_rng sysfs attribute shows currently selected rng. So this new attribute can contain 1 to indicate user's choice, 0 otherwise. Regards, PrasannaKumar
[PATCH 3/3] crypto: hwrng add sysfs attribute to show user selected rng
This patch introduces a new sysfs attribute file 'rng_selected' which shows the the rng chosen by userspace. If a rng source is chosen by user via echo some valid string to rng_current there should be a way to signal this choice to userspace. The new attribute file 'rng_selected' shows either the name of the rng chosen or 'none'. Signed-off-by: Harald Freudenberger --- drivers/char/hw_random/core.c | 22 +- 1 file changed, 17 insertions(+), 5 deletions(-) diff --git a/drivers/char/hw_random/core.c b/drivers/char/hw_random/core.c index ffd4e36..6a6276a 100644 --- a/drivers/char/hw_random/core.c +++ b/drivers/char/hw_random/core.c @@ -28,8 +28,8 @@ #define RNG_MODULE_NAME"hw_random" static struct hwrng *current_rng; -/* the current rng has been explicitly chosen by user via sysfs */ -static int cur_rng_set_by_user; +/* the rng explicitly selected by user via sysfs */ +static struct hwrng *selected_rng; static struct task_struct *hwrng_fill; /* list of registered rngs, sorted decending by quality */ static LIST_HEAD(rng_list); @@ -306,7 +306,7 @@ static ssize_t hwrng_attr_current_store(struct device *dev, list_for_each_entry(rng, &rng_list, list) { if (sysfs_streq(rng->name, buf)) { err = 0; - cur_rng_set_by_user = 1; + selected_rng = rng; if (rng != current_rng) err = set_current_rng(rng); break; @@ -355,16 +355,28 @@ static ssize_t hwrng_attr_available_show(struct device *dev, return strlen(buf); } +static ssize_t hwrng_attr_selected_show(struct device *dev, + struct device_attribute *attr, + char *buf) +{ + return snprintf(buf, PAGE_SIZE, "%s\n", + selected_rng ? selected_rng->name : "none"); +} + static DEVICE_ATTR(rng_current, S_IRUGO | S_IWUSR, hwrng_attr_current_show, hwrng_attr_current_store); static DEVICE_ATTR(rng_available, S_IRUGO, hwrng_attr_available_show, NULL); +static DEVICE_ATTR(rng_selected, S_IRUGO, + hwrng_attr_selected_show, + NULL); static struct attribute *rng_dev_attrs[] = { &dev_attr_rng_current.attr, &dev_attr_rng_available.attr, + &dev_attr_rng_selected.attr, NULL }; @@ -448,7 +460,7 @@ int hwrng_register(struct hwrng *rng) old_rng = current_rng; err = 0; if (!old_rng || - (!cur_rng_set_by_user && rng->quality > old_rng->quality)) { + (!selected_rng && rng->quality > old_rng->quality)) { /* * Set new rng as current as the new rng source * provides better entropy quality and was not @@ -484,7 +496,7 @@ void hwrng_unregister(struct hwrng *rng) list_del(&rng->list); if (current_rng == rng) { drop_current_rng(); - cur_rng_set_by_user = 0; + selected_rng = NULL; /* rng_list is sorted by quality, use the best (=first) one */ if (!list_empty(&rng_list)) { struct hwrng *new_rng; -- 2.7.4