Mercurial > dropbear
view libtomcrypt/src/mac/blake2/blake2bmac_memory_multi.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" #include <stdarg.h> #ifdef LTC_BLAKE2BMAC /** BLAKE2B MAC multiple blocks of memory to produce the authentication tag @param key The secret key @param keylen The length of the secret key (octets) @param mac [out] Destination of the authentication tag @param maclen [in/out] Max size and resulting size of authentication tag @param in The data to BLAKE2B MAC @param inlen The length of the data to BLAKE2B MAC (octets) @param ... tuples of (data,len) pairs to BLAKE2B MAC, terminated with a (NULL,x) (x=don't care) @return CRYPT_OK if successful */ int blake2bmac_memory_multi(const unsigned char *key, unsigned long keylen, unsigned char *mac, unsigned long *maclen, const unsigned char *in, unsigned long inlen, ...) { blake2bmac_state st; int err; va_list args; const unsigned char *curptr; unsigned long curlen; LTC_ARGCHK(key != NULL); LTC_ARGCHK(in != NULL); LTC_ARGCHK(mac != NULL); LTC_ARGCHK(maclen != NULL); va_start(args, inlen); curptr = in; curlen = inlen; if ((err = blake2bmac_init(&st, *maclen, key, keylen)) != CRYPT_OK) { goto LBL_ERR; } for (;;) { if ((err = blake2bmac_process(&st, curptr, curlen)) != CRYPT_OK) { goto LBL_ERR; } curptr = va_arg(args, const unsigned char*); if (curptr == NULL) break; curlen = va_arg(args, unsigned long); } err = blake2bmac_done(&st, mac, maclen); LBL_ERR: #ifdef LTC_CLEAN_STACK zeromem(&st, sizeof(blake2bmac_state)); #endif va_end(args); return err; } #endif /* ref: $Format:%D$ */ /* git commit: $Format:%H$ */ /* commit time: $Format:%ai$ */