| Message ID | 20210216164016.635125-1-sean.anderson@seco.com |
|---|---|
| State | Accepted |
| Commit | 8f684bc12034721585f6412e39155898c8db3d65 |
| Delegated to: | Tom Rini |
| Headers | show |
| Series | lib: rsa: Add debug message on algo mismatch | expand |
Dear Sean Anderson, In message <20210216164016.635125-1-sean.anderson@seco.com> you wrote: > Currently we fail silently if there is an algorithm mismatch. To help > distinguish this failure condition. > > Signed-off-by: Sean Anderson <sean.anderson@seco.com> > --- > > lib/rsa/rsa-verify.c | 5 ++++- > 1 file changed, 4 insertions(+), 1 deletion(-) > > diff --git a/lib/rsa/rsa-verify.c b/lib/rsa/rsa-verify.c > index e34d3293d1..aee76f42d5 100644 > --- a/lib/rsa/rsa-verify.c > +++ b/lib/rsa/rsa-verify.c > @@ -447,8 +447,11 @@ static int rsa_verify_with_keynode(struct image_sign_info *info, > } > > algo = fdt_getprop(blob, node, "algo", NULL); > - if (strcmp(info->name, algo)) > + if (strcmp(info->name, algo)) { > + debug("%s: Wrong algo: have %s, expected %s", __func__, > + info->name, algo); > return -EFAULT; > + } If this is considered an error, should that not be a printf() then instead of a debug() which users will never see? Best regards, Wolfgang Denk
On 2/16/21 12:01 PM, Wolfgang Denk wrote: > Dear Sean Anderson, > > In message <20210216164016.635125-1-sean.anderson@seco.com> you wrote: >> Currently we fail silently if there is an algorithm mismatch. To help >> distinguish this failure condition. >> >> Signed-off-by: Sean Anderson <sean.anderson@seco.com> >> --- >> >> lib/rsa/rsa-verify.c | 5 ++++- >> 1 file changed, 4 insertions(+), 1 deletion(-) >> >> diff --git a/lib/rsa/rsa-verify.c b/lib/rsa/rsa-verify.c >> index e34d3293d1..aee76f42d5 100644 >> --- a/lib/rsa/rsa-verify.c >> +++ b/lib/rsa/rsa-verify.c >> @@ -447,8 +447,11 @@ static int rsa_verify_with_keynode(struct image_sign_info *info, >> } >> >> algo = fdt_getprop(blob, node, "algo", NULL); >> - if (strcmp(info->name, algo)) >> + if (strcmp(info->name, algo)) { >> + debug("%s: Wrong algo: have %s, expected %s", __func__, >> + info->name, algo); >> return -EFAULT; >> + } > > If this is considered an error, should that not be a printf() then > instead of a debug() which users will never see? I also thought that, but the much of the rest of this file also uses debug() to report errors. Perhaps there are security implications? Or perhaps it was done to reduce binary size? Simon, can you comment on this? --Sean > > Best regards, > > Wolfgang Denk >
Hi Sean, On Tue, 16 Feb 2021 at 10:05, Sean Anderson <sean.anderson@seco.com> wrote: > > > > On 2/16/21 12:01 PM, Wolfgang Denk wrote: > > Dear Sean Anderson, > > > > In message <20210216164016.635125-1-sean.anderson@seco.com> you wrote: > >> Currently we fail silently if there is an algorithm mismatch. To help > >> distinguish this failure condition. > >> > >> Signed-off-by: Sean Anderson <sean.anderson@seco.com> > >> --- > >> > >> lib/rsa/rsa-verify.c | 5 ++++- > >> 1 file changed, 4 insertions(+), 1 deletion(-) > >> > >> diff --git a/lib/rsa/rsa-verify.c b/lib/rsa/rsa-verify.c > >> index e34d3293d1..aee76f42d5 100644 > >> --- a/lib/rsa/rsa-verify.c > >> +++ b/lib/rsa/rsa-verify.c > >> @@ -447,8 +447,11 @@ static int rsa_verify_with_keynode(struct image_sign_info *info, > >> } > >> > >> algo = fdt_getprop(blob, node, "algo", NULL); > >> - if (strcmp(info->name, algo)) > >> + if (strcmp(info->name, algo)) { > >> + debug("%s: Wrong algo: have %s, expected %s", __func__, > >> + info->name, algo); > >> return -EFAULT; > >> + } > > > > If this is considered an error, should that not be a printf() then > > instead of a debug() which users will never see? > > I also thought that, but the much of the rest of this file also uses > debug() to report errors. Perhaps there are security implications? Or > perhaps it was done to reduce binary size? Simon, can you comment on > this? In general should not print messages in the bowels of the code, since then there is no way to control what is printed. So long as the error is produced it can be reported and propagated up, and you can document what the different error codes mean. It also bloats the code to include strings everywhere. I suggest adding logging around the return value as it makes it easy to trace things: CONFIG_LOG_ERROR_RETURN=y and return the error with: return log_msg_ret("algo", -EFAULT) Regards, Simon
On Tue, Feb 16, 2021 at 11:40:15AM -0500, Sean Anderson wrote: > Currently we fail silently if there is an algorithm mismatch. To help > distinguish this failure condition. > > Signed-off-by: Sean Anderson <sean.anderson@seco.com> Applied to u-boot/master, thanks!
diff --git a/lib/rsa/rsa-verify.c b/lib/rsa/rsa-verify.c index e34d3293d1..aee76f42d5 100644 --- a/lib/rsa/rsa-verify.c +++ b/lib/rsa/rsa-verify.c @@ -447,8 +447,11 @@ static int rsa_verify_with_keynode(struct image_sign_info *info, } algo = fdt_getprop(blob, node, "algo", NULL); - if (strcmp(info->name, algo)) + if (strcmp(info->name, algo)) { + debug("%s: Wrong algo: have %s, expected %s", __func__, + info->name, algo); return -EFAULT; + } prop.num_bits = fdtdec_get_int(blob, node, "rsa,num-bits", 0);
Currently we fail silently if there is an algorithm mismatch. To help distinguish this failure condition. Signed-off-by: Sean Anderson <sean.anderson@seco.com> --- lib/rsa/rsa-verify.c | 5 ++++- 1 file changed, 4 insertions(+), 1 deletion(-)