Mercurial > dropbear
annotate libtommath/bn_mp_from_sbin.c @ 1930:299f4f19ba19
Add /usr/sbin and /sbin to default root PATH
When dropbear is used in a very restricted environment (such as in a
initrd), the default user shell is often also very restricted
and doesn't take care of setting the PATH so the user ends up
with the PATH set by dropbear. Unfortunately, dropbear always
sets "/usr/bin:/bin" as default PATH even for the root user
which should have /usr/sbin and /sbin too.
For a concrete instance of this problem, see the "Remote Unlocking"
section in this tutorial: https://paxswill.com/blog/2013/11/04/encrypted-raspberry-pi/
It speaks of a bug in the initramfs script because it's written "blkid"
instead of "/sbin/blkid"... this is just because the scripts from the
initramfs do not expect to have a PATH without the sbin directories and
because dropbear is not setting the PATH appropriately for the root user.
I'm thus suggesting to use the attached patch to fix this misbehaviour (I
did not test it, but it's easy enough). It might seem anecdotic but
multiple Kali users have been bitten by this.
From https://bugs.debian.org/cgi-bin/bugreport.cgi?bug=903403
author | Raphael Hertzog <hertzog@debian.org> |
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date | Mon, 09 Jul 2018 16:27:53 +0200 |
parents | 1051e4eea25a |
children |
rev | line source |
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1692
1051e4eea25a
Update LibTomMath to 1.2.0 (#84)
Steffen Jaeckel <s@jaeckel.eu>
parents:
diff
changeset
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1 #include "tommath_private.h" |
1051e4eea25a
Update LibTomMath to 1.2.0 (#84)
Steffen Jaeckel <s@jaeckel.eu>
parents:
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2 #ifdef BN_MP_FROM_SBIN_C |
1051e4eea25a
Update LibTomMath to 1.2.0 (#84)
Steffen Jaeckel <s@jaeckel.eu>
parents:
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3 /* LibTomMath, multiple-precision integer library -- Tom St Denis */ |
1051e4eea25a
Update LibTomMath to 1.2.0 (#84)
Steffen Jaeckel <s@jaeckel.eu>
parents:
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4 /* SPDX-License-Identifier: Unlicense */ |
1051e4eea25a
Update LibTomMath to 1.2.0 (#84)
Steffen Jaeckel <s@jaeckel.eu>
parents:
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5 |
1051e4eea25a
Update LibTomMath to 1.2.0 (#84)
Steffen Jaeckel <s@jaeckel.eu>
parents:
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6 /* read signed bin, big endian, first byte is 0==positive or 1==negative */ |
1051e4eea25a
Update LibTomMath to 1.2.0 (#84)
Steffen Jaeckel <s@jaeckel.eu>
parents:
diff
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7 mp_err mp_from_sbin(mp_int *a, const unsigned char *buf, size_t size) |
1051e4eea25a
Update LibTomMath to 1.2.0 (#84)
Steffen Jaeckel <s@jaeckel.eu>
parents:
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8 { |
1051e4eea25a
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Steffen Jaeckel <s@jaeckel.eu>
parents:
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9 mp_err err; |
1051e4eea25a
Update LibTomMath to 1.2.0 (#84)
Steffen Jaeckel <s@jaeckel.eu>
parents:
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10 |
1051e4eea25a
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Steffen Jaeckel <s@jaeckel.eu>
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11 /* read magnitude */ |
1051e4eea25a
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Steffen Jaeckel <s@jaeckel.eu>
parents:
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12 if ((err = mp_from_ubin(a, buf + 1, size - 1u)) != MP_OKAY) { |
1051e4eea25a
Update LibTomMath to 1.2.0 (#84)
Steffen Jaeckel <s@jaeckel.eu>
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13 return err; |
1051e4eea25a
Update LibTomMath to 1.2.0 (#84)
Steffen Jaeckel <s@jaeckel.eu>
parents:
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14 } |
1051e4eea25a
Update LibTomMath to 1.2.0 (#84)
Steffen Jaeckel <s@jaeckel.eu>
parents:
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15 |
1051e4eea25a
Update LibTomMath to 1.2.0 (#84)
Steffen Jaeckel <s@jaeckel.eu>
parents:
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16 /* first byte is 0 for positive, non-zero for negative */ |
1051e4eea25a
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parents:
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17 if (buf[0] == (unsigned char)0) { |
1051e4eea25a
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18 a->sign = MP_ZPOS; |
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19 } else { |
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Steffen Jaeckel <s@jaeckel.eu>
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20 a->sign = MP_NEG; |
1051e4eea25a
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Steffen Jaeckel <s@jaeckel.eu>
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21 } |
1051e4eea25a
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22 |
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23 return MP_OKAY; |
1051e4eea25a
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24 } |
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Steffen Jaeckel <s@jaeckel.eu>
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25 #endif |