Mercurial > dropbear
view libtomcrypt/src/modes/lrw/lrw_setiv.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> |
---|---|
date | Mon, 09 Jul 2018 16:27:53 +0200 |
parents | 6dba84798cd5 |
children |
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/* LibTomCrypt, modular cryptographic library -- Tom St Denis * * LibTomCrypt is a library that provides various cryptographic * algorithms in a highly modular and flexible manner. * * The library is free for all purposes without any express * guarantee it works. */ #include "tomcrypt.h" /** @file lrw_setiv.c LRW_MODE implementation, Set the current IV, Tom St Denis */ #ifdef LTC_LRW_MODE /** Set the IV for LRW @param IV The IV, must be 16 octets @param len Length ... must be 16 :-) @param lrw The LRW state to update @return CRYPT_OK if successful */ int lrw_setiv(const unsigned char *IV, unsigned long len, symmetric_LRW *lrw) { int err; #ifdef LTC_LRW_TABLES unsigned char T[16]; int x, y; #endif LTC_ARGCHK(IV != NULL); LTC_ARGCHK(lrw != NULL); if (len != 16) { return CRYPT_INVALID_ARG; } if ((err = cipher_is_valid(lrw->cipher)) != CRYPT_OK) { return err; } /* copy the IV */ XMEMCPY(lrw->IV, IV, 16); /* check if we have to actually do work */ if (cipher_descriptor[lrw->cipher].accel_lrw_encrypt != NULL && cipher_descriptor[lrw->cipher].accel_lrw_decrypt != NULL) { /* we have accelerators, let's bail since they don't use lrw->pad anyways */ return CRYPT_OK; } #ifdef LTC_LRW_TABLES XMEMCPY(T, &lrw->PC[0][IV[0]][0], 16); for (x = 1; x < 16; x++) { #ifdef LTC_FAST for (y = 0; y < 16; y += sizeof(LTC_FAST_TYPE)) { *(LTC_FAST_TYPE_PTR_CAST(T + y)) ^= *(LTC_FAST_TYPE_PTR_CAST(&lrw->PC[x][IV[x]][y])); } #else for (y = 0; y < 16; y++) { T[y] ^= lrw->PC[x][IV[x]][y]; } #endif } XMEMCPY(lrw->pad, T, 16); #else gcm_gf_mult(lrw->tweak, IV, lrw->pad); #endif return CRYPT_OK; } #endif /* ref: $Format:%D$ */ /* git commit: $Format:%H$ */ /* commit time: $Format:%ai$ */