Message ID | 20190115025437.11966-2-takahiro.akashi@linaro.org |
---|---|
State | Superseded, archived |
Delegated to: | Heinrich Schuchardt |
Headers | show |
Series | efi_loader: run a specific efi application more easily | expand |
On 1/15/19 3:54 AM, AKASHI Takahiro wrote: > See UEFI v2.7, section 3.1.2 for details of the specification. > > With my efitool command, you can try as the following: > => efi boot add 1 SHELL ... > => efi boot add 2 HELLO ... > => efi boot order 1 2 > => efi bootmgr > (starting SHELL ...) > => efi boot next 2 > => efi bootmgr > (starting HELLO ...) > => efi dumpvar > <snip ...> > BootCurrent: {boot,run}(blob) > 00000000: 02 00 .. > BootOrder: {boot,run}(blob) > 00000000: 01 00 02 00 .... > > Signed-off-by: AKASHI Takahiro <takahiro.akashi@linaro.org> > --- > lib/efi_loader/efi_bootmgr.c | 34 +++++++++++++++++++++++++++++++++- > 1 file changed, 33 insertions(+), 1 deletion(-) > > diff --git a/lib/efi_loader/efi_bootmgr.c b/lib/efi_loader/efi_bootmgr.c > index a095df3f540b..6c5303736dc6 100644 > --- a/lib/efi_loader/efi_bootmgr.c > +++ b/lib/efi_loader/efi_bootmgr.c > @@ -145,11 +145,21 @@ static void *try_load_entry(uint16_t n, struct efi_device_path **device_path, > efi_deserialize_load_option(&lo, load_option); > > if (lo.attributes & LOAD_OPTION_ACTIVE) { > + u32 attributes; > efi_status_t ret; > > debug("%s: trying to load \"%ls\" from %pD\n", > __func__, lo.label, lo.file_path); > > + attributes = EFI_VARIABLE_BOOTSERVICE_ACCESS | > + EFI_VARIABLE_RUNTIME_ACCESS; > + size = sizeof(n); > + ret = rs->set_variable(L"BootCurrent", > + (efi_guid_t *)&efi_global_variable_guid, Use EFI_CALL(). Instead of dereferencing you could directly call efi_set_variable(). > + attributes, size, &n); > + if (ret != EFI_SUCCESS) > + goto error; > + > ret = efi_load_image_from_path(lo.file_path, &image); > > if (ret != EFI_SUCCESS) > @@ -173,16 +183,38 @@ error: > void *efi_bootmgr_load(struct efi_device_path **device_path, > struct efi_device_path **file_path) > { > - uint16_t *bootorder; > + u16 bootnext, *bootorder; > efi_uintn_t size; > void *image = NULL; > int i, num; > + efi_status_t ret; > > __efi_entry_check(); > > bs = systab.boottime; > rs = systab.runtime; > > + /* get BootNext */ > + size = sizeof(bootnext); > + ret = rs->get_variable(L"BootNext", > + (efi_guid_t *)&efi_global_variable_guid, > + NULL, &size, &bootnext); You could call efi_get_variable() directly instead of dereferencing rs. But anyway you have to use EFI_CALL(). > + if (!bootnext) > + goto run_list; Goto is acceptable for error handling. But otherwise I would rather avoid it. > + > + /* delete BootNext */ > + ret = rs->set_variable(L"BootNext", > + (efi_guid_t *)&efi_global_variable_guid, > + 0, 0, &bootnext); EFI_CALL(). Best regards Heinrich > + if (ret != EFI_SUCCESS) > + goto error; > + > + image = try_load_entry(bootnext, device_path, file_path); > + if (image) > + goto error; > + > +run_list: > + /* BootOrder */ > bootorder = get_var(L"BootOrder", &efi_global_variable_guid, &size); > if (!bootorder) > goto error; >
On Tue, Feb 26, 2019 at 07:57:26PM +0100, Heinrich Schuchardt wrote: > On 1/15/19 3:54 AM, AKASHI Takahiro wrote: > > See UEFI v2.7, section 3.1.2 for details of the specification. > > > > With my efitool command, you can try as the following: > > => efi boot add 1 SHELL ... > > => efi boot add 2 HELLO ... > > => efi boot order 1 2 > > => efi bootmgr > > (starting SHELL ...) > > => efi boot next 2 > > => efi bootmgr > > (starting HELLO ...) > > => efi dumpvar > > <snip ...> > > BootCurrent: {boot,run}(blob) > > 00000000: 02 00 .. > > BootOrder: {boot,run}(blob) > > 00000000: 01 00 02 00 .... > > > > Signed-off-by: AKASHI Takahiro <takahiro.akashi@linaro.org> > > --- > > lib/efi_loader/efi_bootmgr.c | 34 +++++++++++++++++++++++++++++++++- > > 1 file changed, 33 insertions(+), 1 deletion(-) > > > > diff --git a/lib/efi_loader/efi_bootmgr.c b/lib/efi_loader/efi_bootmgr.c > > index a095df3f540b..6c5303736dc6 100644 > > --- a/lib/efi_loader/efi_bootmgr.c > > +++ b/lib/efi_loader/efi_bootmgr.c > > @@ -145,11 +145,21 @@ static void *try_load_entry(uint16_t n, struct efi_device_path **device_path, > > efi_deserialize_load_option(&lo, load_option); > > > > if (lo.attributes & LOAD_OPTION_ACTIVE) { > > + u32 attributes; > > efi_status_t ret; > > > > debug("%s: trying to load \"%ls\" from %pD\n", > > __func__, lo.label, lo.file_path); > > > > + attributes = EFI_VARIABLE_BOOTSERVICE_ACCESS | > > + EFI_VARIABLE_RUNTIME_ACCESS; > > + size = sizeof(n); > > + ret = rs->set_variable(L"BootCurrent", > > + (efi_guid_t *)&efi_global_variable_guid, > > Use EFI_CALL(). Okay But as I said somewhere else, it's quite annoying to me that some efi_xxx requires EFI_CALL(), and others not. There should have been consistent naming rules. > Instead of dereferencing you could directly call > efi_set_variable(). Yeah, given that this code is under lib/efi_loader, it may be natural to use efi_set_variable(). But existing get_var() uses the same style of coding. Do you want to change all of the call sites including get_var()? > > + attributes, size, &n); > > + if (ret != EFI_SUCCESS) > > + goto error; > > + > > ret = efi_load_image_from_path(lo.file_path, &image); > > > > if (ret != EFI_SUCCESS) > > @@ -173,16 +183,38 @@ error: > > void *efi_bootmgr_load(struct efi_device_path **device_path, > > struct efi_device_path **file_path) > > { > > - uint16_t *bootorder; > > + u16 bootnext, *bootorder; > > efi_uintn_t size; > > void *image = NULL; > > int i, num; > > + efi_status_t ret; > > > > __efi_entry_check(); > > > > bs = systab.boottime; > > rs = systab.runtime; > > > > + /* get BootNext */ > > + size = sizeof(bootnext); > > + ret = rs->get_variable(L"BootNext", > > + (efi_guid_t *)&efi_global_variable_guid, > > + NULL, &size, &bootnext); > > You could call efi_get_variable() directly instead of dereferencing rs. > But anyway you have to use EFI_CALL(). Ditto > > + if (!bootnext) > > + goto run_list; > > Goto is acceptable for error handling. But otherwise I would rather > avoid it. Okay with another indentation. > > + > > + /* delete BootNext */ > > + ret = rs->set_variable(L"BootNext", > > + (efi_guid_t *)&efi_global_variable_guid, > > + 0, 0, &bootnext); > > EFI_CALL(). Thanks, -Takahiro Akashi > Best regards > > Heinrich > > > + if (ret != EFI_SUCCESS) > > + goto error; > > + > > + image = try_load_entry(bootnext, device_path, file_path); > > + if (image) > > + goto error; > > + > > +run_list: > > + /* BootOrder */ > > bootorder = get_var(L"BootOrder", &efi_global_variable_guid, &size); > > if (!bootorder) > > goto error; > > >
On 2/27/19 6:47 AM, AKASHI Takahiro wrote: > On Tue, Feb 26, 2019 at 07:57:26PM +0100, Heinrich Schuchardt wrote: >> On 1/15/19 3:54 AM, AKASHI Takahiro wrote: >>> See UEFI v2.7, section 3.1.2 for details of the specification. >>> >>> With my efitool command, you can try as the following: >>> => efi boot add 1 SHELL ... >>> => efi boot add 2 HELLO ... >>> => efi boot order 1 2 >>> => efi bootmgr >>> (starting SHELL ...) >>> => efi boot next 2 >>> => efi bootmgr >>> (starting HELLO ...) >>> => efi dumpvar >>> <snip ...> >>> BootCurrent: {boot,run}(blob) >>> 00000000: 02 00 .. >>> BootOrder: {boot,run}(blob) >>> 00000000: 01 00 02 00 .... >>> >>> Signed-off-by: AKASHI Takahiro <takahiro.akashi@linaro.org> >>> --- >>> lib/efi_loader/efi_bootmgr.c | 34 +++++++++++++++++++++++++++++++++- >>> 1 file changed, 33 insertions(+), 1 deletion(-) >>> >>> diff --git a/lib/efi_loader/efi_bootmgr.c b/lib/efi_loader/efi_bootmgr.c >>> index a095df3f540b..6c5303736dc6 100644 >>> --- a/lib/efi_loader/efi_bootmgr.c >>> +++ b/lib/efi_loader/efi_bootmgr.c >>> @@ -145,11 +145,21 @@ static void *try_load_entry(uint16_t n, struct efi_device_path **device_path, >>> efi_deserialize_load_option(&lo, load_option); >>> >>> if (lo.attributes & LOAD_OPTION_ACTIVE) { >>> + u32 attributes; >>> efi_status_t ret; >>> >>> debug("%s: trying to load \"%ls\" from %pD\n", >>> __func__, lo.label, lo.file_path); >>> >>> + attributes = EFI_VARIABLE_BOOTSERVICE_ACCESS | >>> + EFI_VARIABLE_RUNTIME_ACCESS; >>> + size = sizeof(n); >>> + ret = rs->set_variable(L"BootCurrent", >>> + (efi_guid_t *)&efi_global_variable_guid, >> >> Use EFI_CALL(). > > Okay > But as I said somewhere else, it's quite annoying to me that > some efi_xxx requires EFI_CALL(), and others not. > There should have been consistent naming rules. We started with having separate functions like efi_allocate_pages_ext() and efi_allocate_pages(). Then Rob Clark came along and introduced EFI_CALL() in a095aadffa96 and I stopped creating _ext() functions. When running with DEBUG 1 it sometimes is helpful to see which function is calling which other and where errors are originally reported. But I am open to changes in this area. > >> Instead of dereferencing you could directly call >> efi_set_variable(). > > Yeah, given that this code is under lib/efi_loader, it may be natural > to use efi_set_variable(). But existing get_var() uses the same style of coding. > > Do you want to change all of the call sites including get_var()? Calling efi_set_variable() directly uses less bytes of code than rs->get_variable() which makes it preferable. I have seen that iPXE modifies system->boottime to intercept system calls. The same could be done by an EFI driver to the runtime vectors. In the light of your work on secure boot I think we should not allow an EFI driver to intercept the reading and changing of variables here. We should also rethink it for efidebug.c Best regards Heinrich > >>> + attributes, size, &n); >>> + if (ret != EFI_SUCCESS) >>> + goto error; >>> + >>> ret = efi_load_image_from_path(lo.file_path, &image); >>> >>> if (ret != EFI_SUCCESS) >>> @@ -173,16 +183,38 @@ error: >>> void *efi_bootmgr_load(struct efi_device_path **device_path, >>> struct efi_device_path **file_path) >>> { >>> - uint16_t *bootorder; >>> + u16 bootnext, *bootorder; >>> efi_uintn_t size; >>> void *image = NULL; >>> int i, num; >>> + efi_status_t ret; >>> >>> __efi_entry_check(); >>> >>> bs = systab.boottime; >>> rs = systab.runtime; >>> >>> + /* get BootNext */ >>> + size = sizeof(bootnext); >>> + ret = rs->get_variable(L"BootNext", >>> + (efi_guid_t *)&efi_global_variable_guid, >>> + NULL, &size, &bootnext); >> >> You could call efi_get_variable() directly instead of dereferencing rs. >> But anyway you have to use EFI_CALL(). > > Ditto > >>> + if (!bootnext) >>> + goto run_list; >> >> Goto is acceptable for error handling. But otherwise I would rather >> avoid it. > > Okay with another indentation. > >>> + >>> + /* delete BootNext */ >>> + ret = rs->set_variable(L"BootNext", >>> + (efi_guid_t *)&efi_global_variable_guid, >>> + 0, 0, &bootnext); >> >> EFI_CALL(). > > Thanks, > -Takahiro Akashi > >> Best regards >> >> Heinrich >> >>> + if (ret != EFI_SUCCESS) >>> + goto error; >>> + >>> + image = try_load_entry(bootnext, device_path, file_path); >>> + if (image) >>> + goto error; >>> + >>> +run_list: >>> + /* BootOrder */ >>> bootorder = get_var(L"BootOrder", &efi_global_variable_guid, &size); >>> if (!bootorder) >>> goto error; >>> >> >
On Wed, Feb 27, 2019 at 07:14:10AM +0100, Heinrich Schuchardt wrote: > On 2/27/19 6:47 AM, AKASHI Takahiro wrote: > > On Tue, Feb 26, 2019 at 07:57:26PM +0100, Heinrich Schuchardt wrote: > >> On 1/15/19 3:54 AM, AKASHI Takahiro wrote: > >>> See UEFI v2.7, section 3.1.2 for details of the specification. > >>> > >>> With my efitool command, you can try as the following: > >>> => efi boot add 1 SHELL ... > >>> => efi boot add 2 HELLO ... > >>> => efi boot order 1 2 > >>> => efi bootmgr > >>> (starting SHELL ...) > >>> => efi boot next 2 > >>> => efi bootmgr > >>> (starting HELLO ...) > >>> => efi dumpvar > >>> <snip ...> > >>> BootCurrent: {boot,run}(blob) > >>> 00000000: 02 00 .. > >>> BootOrder: {boot,run}(blob) > >>> 00000000: 01 00 02 00 .... > >>> > >>> Signed-off-by: AKASHI Takahiro <takahiro.akashi@linaro.org> > >>> --- > >>> lib/efi_loader/efi_bootmgr.c | 34 +++++++++++++++++++++++++++++++++- > >>> 1 file changed, 33 insertions(+), 1 deletion(-) > >>> > >>> diff --git a/lib/efi_loader/efi_bootmgr.c b/lib/efi_loader/efi_bootmgr.c > >>> index a095df3f540b..6c5303736dc6 100644 > >>> --- a/lib/efi_loader/efi_bootmgr.c > >>> +++ b/lib/efi_loader/efi_bootmgr.c > >>> @@ -145,11 +145,21 @@ static void *try_load_entry(uint16_t n, struct efi_device_path **device_path, > >>> efi_deserialize_load_option(&lo, load_option); > >>> > >>> if (lo.attributes & LOAD_OPTION_ACTIVE) { > >>> + u32 attributes; > >>> efi_status_t ret; > >>> > >>> debug("%s: trying to load \"%ls\" from %pD\n", > >>> __func__, lo.label, lo.file_path); > >>> > >>> + attributes = EFI_VARIABLE_BOOTSERVICE_ACCESS | > >>> + EFI_VARIABLE_RUNTIME_ACCESS; > >>> + size = sizeof(n); > >>> + ret = rs->set_variable(L"BootCurrent", > >>> + (efi_guid_t *)&efi_global_variable_guid, > >> > >> Use EFI_CALL(). > > > > Okay > > But as I said somewhere else, it's quite annoying to me that > > some efi_xxx requires EFI_CALL(), and others not. > > There should have been consistent naming rules. > > We started with having separate functions like efi_allocate_pages_ext() > and efi_allocate_pages(). Then Rob Clark came along and introduced > EFI_CALL() in a095aadffa96 and I stopped creating _ext() functions. > > When running with DEBUG 1 it sometimes is helpful to see which function > is calling which other and where errors are originally reported. > > But I am open to changes in this area. > > > > >> Instead of dereferencing you could directly call > >> efi_set_variable(). > > > > Yeah, given that this code is under lib/efi_loader, it may be natural > > to use efi_set_variable(). But existing get_var() uses the same style of coding. > > > > Do you want to change all of the call sites including get_var()? > > Calling efi_set_variable() directly uses less bytes of code than > rs->get_variable() which makes it preferable. So is your answer yes, or no? > I have seen that iPXE modifies system->boottime to intercept system > calls. The same could be done by an EFI driver to the runtime vectors. > > In the light of your work on secure boot I think we should not allow an > EFI driver to intercept the reading and changing of variables here. > > We should also rethink it for efidebug.c I'm not sure about your concern here, but no doubt efidebug should be disabled on production system with secure boot. Thanks, -Takahiro Akashi > Best regards > > Heinrich > > > > >>> + attributes, size, &n); > >>> + if (ret != EFI_SUCCESS) > >>> + goto error; > >>> + > >>> ret = efi_load_image_from_path(lo.file_path, &image); > >>> > >>> if (ret != EFI_SUCCESS) > >>> @@ -173,16 +183,38 @@ error: > >>> void *efi_bootmgr_load(struct efi_device_path **device_path, > >>> struct efi_device_path **file_path) > >>> { > >>> - uint16_t *bootorder; > >>> + u16 bootnext, *bootorder; > >>> efi_uintn_t size; > >>> void *image = NULL; > >>> int i, num; > >>> + efi_status_t ret; > >>> > >>> __efi_entry_check(); > >>> > >>> bs = systab.boottime; > >>> rs = systab.runtime; > >>> > >>> + /* get BootNext */ > >>> + size = sizeof(bootnext); > >>> + ret = rs->get_variable(L"BootNext", > >>> + (efi_guid_t *)&efi_global_variable_guid, > >>> + NULL, &size, &bootnext); > >> > >> You could call efi_get_variable() directly instead of dereferencing rs. > >> But anyway you have to use EFI_CALL(). > > > > Ditto > > > >>> + if (!bootnext) > >>> + goto run_list; > >> > >> Goto is acceptable for error handling. But otherwise I would rather > >> avoid it. > > > > Okay with another indentation. > > > >>> + > >>> + /* delete BootNext */ > >>> + ret = rs->set_variable(L"BootNext", > >>> + (efi_guid_t *)&efi_global_variable_guid, > >>> + 0, 0, &bootnext); > >> > >> EFI_CALL(). > > > > Thanks, > > -Takahiro Akashi > > > >> Best regards > >> > >> Heinrich > >> > >>> + if (ret != EFI_SUCCESS) > >>> + goto error; > >>> + > >>> + image = try_load_entry(bootnext, device_path, file_path); > >>> + if (image) > >>> + goto error; > >>> + > >>> +run_list: > >>> + /* BootOrder */ > >>> bootorder = get_var(L"BootOrder", &efi_global_variable_guid, &size); > >>> if (!bootorder) > >>> goto error; > >>> > >> > > >
On 2/27/19 7:27 AM, AKASHI Takahiro wrote: > On Wed, Feb 27, 2019 at 07:14:10AM +0100, Heinrich Schuchardt wrote: >> On 2/27/19 6:47 AM, AKASHI Takahiro wrote: >>> On Tue, Feb 26, 2019 at 07:57:26PM +0100, Heinrich Schuchardt wrote: >>>> On 1/15/19 3:54 AM, AKASHI Takahiro wrote: >>>>> See UEFI v2.7, section 3.1.2 for details of the specification. >>>>> >>>>> With my efitool command, you can try as the following: >>>>> => efi boot add 1 SHELL ... >>>>> => efi boot add 2 HELLO ... >>>>> => efi boot order 1 2 >>>>> => efi bootmgr >>>>> (starting SHELL ...) >>>>> => efi boot next 2 >>>>> => efi bootmgr >>>>> (starting HELLO ...) >>>>> => efi dumpvar >>>>> <snip ...> >>>>> BootCurrent: {boot,run}(blob) >>>>> 00000000: 02 00 .. >>>>> BootOrder: {boot,run}(blob) >>>>> 00000000: 01 00 02 00 .... >>>>> >>>>> Signed-off-by: AKASHI Takahiro <takahiro.akashi@linaro.org> >>>>> --- >>>>> lib/efi_loader/efi_bootmgr.c | 34 +++++++++++++++++++++++++++++++++- >>>>> 1 file changed, 33 insertions(+), 1 deletion(-) >>>>> >>>>> diff --git a/lib/efi_loader/efi_bootmgr.c b/lib/efi_loader/efi_bootmgr.c >>>>> index a095df3f540b..6c5303736dc6 100644 >>>>> --- a/lib/efi_loader/efi_bootmgr.c >>>>> +++ b/lib/efi_loader/efi_bootmgr.c >>>>> @@ -145,11 +145,21 @@ static void *try_load_entry(uint16_t n, struct efi_device_path **device_path, >>>>> efi_deserialize_load_option(&lo, load_option); >>>>> >>>>> if (lo.attributes & LOAD_OPTION_ACTIVE) { >>>>> + u32 attributes; >>>>> efi_status_t ret; >>>>> >>>>> debug("%s: trying to load \"%ls\" from %pD\n", >>>>> __func__, lo.label, lo.file_path); >>>>> >>>>> + attributes = EFI_VARIABLE_BOOTSERVICE_ACCESS | >>>>> + EFI_VARIABLE_RUNTIME_ACCESS; >>>>> + size = sizeof(n); >>>>> + ret = rs->set_variable(L"BootCurrent", >>>>> + (efi_guid_t *)&efi_global_variable_guid, >>>> >>>> Use EFI_CALL(). >>> >>> Okay >>> But as I said somewhere else, it's quite annoying to me that >>> some efi_xxx requires EFI_CALL(), and others not. >>> There should have been consistent naming rules. >> >> We started with having separate functions like efi_allocate_pages_ext() >> and efi_allocate_pages(). Then Rob Clark came along and introduced >> EFI_CALL() in a095aadffa96 and I stopped creating _ext() functions. >> >> When running with DEBUG 1 it sometimes is helpful to see which function >> is calling which other and where errors are originally reported. >> >> But I am open to changes in this area. >> >>> >>>> Instead of dereferencing you could directly call >>>> efi_set_variable(). >>> >>> Yeah, given that this code is under lib/efi_loader, it may be natural >>> to use efi_set_variable(). But existing get_var() uses the same style of coding. >>> >>> Do you want to change all of the call sites including get_var()? >> >> Calling efi_set_variable() directly uses less bytes of code than >> rs->get_variable() which makes it preferable. > > So is your answer yes, or no? I would prefer calling efi_get_variable() directly and not to use rs->get_variable(). > >> I have seen that iPXE modifies system->boottime to intercept system >> calls. The same could be done by an EFI driver to the runtime vectors. >> >> In the light of your work on secure boot I think we should not allow an >> EFI driver to intercept the reading and changing of variables here. >> >> We should also rethink it for efidebug.c > > I'm not sure about your concern here, but no doubt efidebug should > be disabled on production system with secure boot. Also in efidebug we are creating more runtime code bytes than needed by using system->runtime->efi_something() or system->boottime->efi_something(). Best regards Heinrich > > Thanks, > -Takahiro Akashi > >> Best regards >> >> Heinrich >> >>> >>>>> + attributes, size, &n); >>>>> + if (ret != EFI_SUCCESS) >>>>> + goto error; >>>>> + >>>>> ret = efi_load_image_from_path(lo.file_path, &image); >>>>> >>>>> if (ret != EFI_SUCCESS) >>>>> @@ -173,16 +183,38 @@ error: >>>>> void *efi_bootmgr_load(struct efi_device_path **device_path, >>>>> struct efi_device_path **file_path) >>>>> { >>>>> - uint16_t *bootorder; >>>>> + u16 bootnext, *bootorder; >>>>> efi_uintn_t size; >>>>> void *image = NULL; >>>>> int i, num; >>>>> + efi_status_t ret; >>>>> >>>>> __efi_entry_check(); >>>>> >>>>> bs = systab.boottime; >>>>> rs = systab.runtime; >>>>> >>>>> + /* get BootNext */ >>>>> + size = sizeof(bootnext); >>>>> + ret = rs->get_variable(L"BootNext", >>>>> + (efi_guid_t *)&efi_global_variable_guid, >>>>> + NULL, &size, &bootnext); >>>> >>>> You could call efi_get_variable() directly instead of dereferencing rs. >>>> But anyway you have to use EFI_CALL(). >>> >>> Ditto >>> >>>>> + if (!bootnext) >>>>> + goto run_list; >>>> >>>> Goto is acceptable for error handling. But otherwise I would rather >>>> avoid it. >>> >>> Okay with another indentation. >>> >>>>> + >>>>> + /* delete BootNext */ >>>>> + ret = rs->set_variable(L"BootNext", >>>>> + (efi_guid_t *)&efi_global_variable_guid, >>>>> + 0, 0, &bootnext); >>>> >>>> EFI_CALL(). >>> >>> Thanks, >>> -Takahiro Akashi >>> >>>> Best regards >>>> >>>> Heinrich >>>> >>>>> + if (ret != EFI_SUCCESS) >>>>> + goto error; >>>>> + >>>>> + image = try_load_entry(bootnext, device_path, file_path); >>>>> + if (image) >>>>> + goto error; >>>>> + >>>>> +run_list: >>>>> + /* BootOrder */ >>>>> bootorder = get_var(L"BootOrder", &efi_global_variable_guid, &size); >>>>> if (!bootorder) >>>>> goto error; >>>>> >>>> >>> >> >
On Wed, Feb 27, 2019 at 07:39:50AM +0100, Heinrich Schuchardt wrote: > On 2/27/19 7:27 AM, AKASHI Takahiro wrote: > > On Wed, Feb 27, 2019 at 07:14:10AM +0100, Heinrich Schuchardt wrote: > >> On 2/27/19 6:47 AM, AKASHI Takahiro wrote: > >>> On Tue, Feb 26, 2019 at 07:57:26PM +0100, Heinrich Schuchardt wrote: > >>>> On 1/15/19 3:54 AM, AKASHI Takahiro wrote: > >>>>> See UEFI v2.7, section 3.1.2 for details of the specification. > >>>>> > >>>>> With my efitool command, you can try as the following: > >>>>> => efi boot add 1 SHELL ... > >>>>> => efi boot add 2 HELLO ... > >>>>> => efi boot order 1 2 > >>>>> => efi bootmgr > >>>>> (starting SHELL ...) > >>>>> => efi boot next 2 > >>>>> => efi bootmgr > >>>>> (starting HELLO ...) > >>>>> => efi dumpvar > >>>>> <snip ...> > >>>>> BootCurrent: {boot,run}(blob) > >>>>> 00000000: 02 00 .. > >>>>> BootOrder: {boot,run}(blob) > >>>>> 00000000: 01 00 02 00 .... > >>>>> > >>>>> Signed-off-by: AKASHI Takahiro <takahiro.akashi@linaro.org> > >>>>> --- > >>>>> lib/efi_loader/efi_bootmgr.c | 34 +++++++++++++++++++++++++++++++++- > >>>>> 1 file changed, 33 insertions(+), 1 deletion(-) > >>>>> > >>>>> diff --git a/lib/efi_loader/efi_bootmgr.c b/lib/efi_loader/efi_bootmgr.c > >>>>> index a095df3f540b..6c5303736dc6 100644 > >>>>> --- a/lib/efi_loader/efi_bootmgr.c > >>>>> +++ b/lib/efi_loader/efi_bootmgr.c > >>>>> @@ -145,11 +145,21 @@ static void *try_load_entry(uint16_t n, struct efi_device_path **device_path, > >>>>> efi_deserialize_load_option(&lo, load_option); > >>>>> > >>>>> if (lo.attributes & LOAD_OPTION_ACTIVE) { > >>>>> + u32 attributes; > >>>>> efi_status_t ret; > >>>>> > >>>>> debug("%s: trying to load \"%ls\" from %pD\n", > >>>>> __func__, lo.label, lo.file_path); > >>>>> > >>>>> + attributes = EFI_VARIABLE_BOOTSERVICE_ACCESS | > >>>>> + EFI_VARIABLE_RUNTIME_ACCESS; > >>>>> + size = sizeof(n); > >>>>> + ret = rs->set_variable(L"BootCurrent", > >>>>> + (efi_guid_t *)&efi_global_variable_guid, > >>>> > >>>> Use EFI_CALL(). > >>> > >>> Okay > >>> But as I said somewhere else, it's quite annoying to me that > >>> some efi_xxx requires EFI_CALL(), and others not. > >>> There should have been consistent naming rules. > >> > >> We started with having separate functions like efi_allocate_pages_ext() > >> and efi_allocate_pages(). Then Rob Clark came along and introduced > >> EFI_CALL() in a095aadffa96 and I stopped creating _ext() functions. > >> > >> When running with DEBUG 1 it sometimes is helpful to see which function > >> is calling which other and where errors are originally reported. > >> > >> But I am open to changes in this area. > >> > >>> > >>>> Instead of dereferencing you could directly call > >>>> efi_set_variable(). > >>> > >>> Yeah, given that this code is under lib/efi_loader, it may be natural > >>> to use efi_set_variable(). But existing get_var() uses the same style of coding. > >>> > >>> Do you want to change all of the call sites including get_var()? > >> > >> Calling efi_set_variable() directly uses less bytes of code than > >> rs->get_variable() which makes it preferable. > > > > So is your answer yes, or no? > > I would prefer calling efi_get_variable() directly and not to use > rs->get_variable(). My point is "including get_var()" or not. I have never touched that function in my patch. > > > >> I have seen that iPXE modifies system->boottime to intercept system > >> calls. The same could be done by an EFI driver to the runtime vectors. > >> > >> In the light of your work on secure boot I think we should not allow an > >> EFI driver to intercept the reading and changing of variables here. > >> > >> We should also rethink it for efidebug.c > > > > I'm not sure about your concern here, but no doubt efidebug should > > be disabled on production system with secure boot. > > Also in efidebug we are creating more runtime code bytes than needed by > using system->runtime->efi_something() or system->boottime->efi_something(). I think we discussed in the past. I prefer to calling boot time/run time services via system table as this command is expected to be implemented as an (embedded) EFI application sometime in the future. Thanks, -Takahiro Akashi > Best regards > > Heinrich > > > > > Thanks, > > -Takahiro Akashi > > > >> Best regards > >> > >> Heinrich > >> > >>> > >>>>> + attributes, size, &n); > >>>>> + if (ret != EFI_SUCCESS) > >>>>> + goto error; > >>>>> + > >>>>> ret = efi_load_image_from_path(lo.file_path, &image); > >>>>> > >>>>> if (ret != EFI_SUCCESS) > >>>>> @@ -173,16 +183,38 @@ error: > >>>>> void *efi_bootmgr_load(struct efi_device_path **device_path, > >>>>> struct efi_device_path **file_path) > >>>>> { > >>>>> - uint16_t *bootorder; > >>>>> + u16 bootnext, *bootorder; > >>>>> efi_uintn_t size; > >>>>> void *image = NULL; > >>>>> int i, num; > >>>>> + efi_status_t ret; > >>>>> > >>>>> __efi_entry_check(); > >>>>> > >>>>> bs = systab.boottime; > >>>>> rs = systab.runtime; > >>>>> > >>>>> + /* get BootNext */ > >>>>> + size = sizeof(bootnext); > >>>>> + ret = rs->get_variable(L"BootNext", > >>>>> + (efi_guid_t *)&efi_global_variable_guid, > >>>>> + NULL, &size, &bootnext); > >>>> > >>>> You could call efi_get_variable() directly instead of dereferencing rs. > >>>> But anyway you have to use EFI_CALL(). > >>> > >>> Ditto > >>> > >>>>> + if (!bootnext) > >>>>> + goto run_list; > >>>> > >>>> Goto is acceptable for error handling. But otherwise I would rather > >>>> avoid it. > >>> > >>> Okay with another indentation. > >>> > >>>>> + > >>>>> + /* delete BootNext */ > >>>>> + ret = rs->set_variable(L"BootNext", > >>>>> + (efi_guid_t *)&efi_global_variable_guid, > >>>>> + 0, 0, &bootnext); > >>>> > >>>> EFI_CALL(). > >>> > >>> Thanks, > >>> -Takahiro Akashi > >>> > >>>> Best regards > >>>> > >>>> Heinrich > >>>> > >>>>> + if (ret != EFI_SUCCESS) > >>>>> + goto error; > >>>>> + > >>>>> + image = try_load_entry(bootnext, device_path, file_path); > >>>>> + if (image) > >>>>> + goto error; > >>>>> + > >>>>> +run_list: > >>>>> + /* BootOrder */ > >>>>> bootorder = get_var(L"BootOrder", &efi_global_variable_guid, &size); > >>>>> if (!bootorder) > >>>>> goto error; > >>>>> > >>>> > >>> > >> > > >
diff --git a/lib/efi_loader/efi_bootmgr.c b/lib/efi_loader/efi_bootmgr.c index a095df3f540b..6c5303736dc6 100644 --- a/lib/efi_loader/efi_bootmgr.c +++ b/lib/efi_loader/efi_bootmgr.c @@ -145,11 +145,21 @@ static void *try_load_entry(uint16_t n, struct efi_device_path **device_path, efi_deserialize_load_option(&lo, load_option); if (lo.attributes & LOAD_OPTION_ACTIVE) { + u32 attributes; efi_status_t ret; debug("%s: trying to load \"%ls\" from %pD\n", __func__, lo.label, lo.file_path); + attributes = EFI_VARIABLE_BOOTSERVICE_ACCESS | + EFI_VARIABLE_RUNTIME_ACCESS; + size = sizeof(n); + ret = rs->set_variable(L"BootCurrent", + (efi_guid_t *)&efi_global_variable_guid, + attributes, size, &n); + if (ret != EFI_SUCCESS) + goto error; + ret = efi_load_image_from_path(lo.file_path, &image); if (ret != EFI_SUCCESS) @@ -173,16 +183,38 @@ error: void *efi_bootmgr_load(struct efi_device_path **device_path, struct efi_device_path **file_path) { - uint16_t *bootorder; + u16 bootnext, *bootorder; efi_uintn_t size; void *image = NULL; int i, num; + efi_status_t ret; __efi_entry_check(); bs = systab.boottime; rs = systab.runtime; + /* get BootNext */ + size = sizeof(bootnext); + ret = rs->get_variable(L"BootNext", + (efi_guid_t *)&efi_global_variable_guid, + NULL, &size, &bootnext); + if (!bootnext) + goto run_list; + + /* delete BootNext */ + ret = rs->set_variable(L"BootNext", + (efi_guid_t *)&efi_global_variable_guid, + 0, 0, &bootnext); + if (ret != EFI_SUCCESS) + goto error; + + image = try_load_entry(bootnext, device_path, file_path); + if (image) + goto error; + +run_list: + /* BootOrder */ bootorder = get_var(L"BootOrder", &efi_global_variable_guid, &size); if (!bootorder) goto error;
See UEFI v2.7, section 3.1.2 for details of the specification. With my efitool command, you can try as the following: => efi boot add 1 SHELL ... => efi boot add 2 HELLO ... => efi boot order 1 2 => efi bootmgr (starting SHELL ...) => efi boot next 2 => efi bootmgr (starting HELLO ...) => efi dumpvar <snip ...> BootCurrent: {boot,run}(blob) 00000000: 02 00 .. BootOrder: {boot,run}(blob) 00000000: 01 00 02 00 .... Signed-off-by: AKASHI Takahiro <takahiro.akashi@linaro.org> --- lib/efi_loader/efi_bootmgr.c | 34 +++++++++++++++++++++++++++++++++- 1 file changed, 33 insertions(+), 1 deletion(-)