Mercurial > dropbear
view libtomcrypt/src/hashes/md4.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" /** @param md4.c Submitted by Dobes Vandermeer ([email protected]) */ #ifdef LTC_MD4 const struct ltc_hash_descriptor md4_desc = { "md4", 6, 16, 64, /* OID */ { 1, 2, 840, 113549, 2, 4, }, 6, &md4_init, &md4_process, &md4_done, &md4_test, NULL }; #define S11 3 #define S12 7 #define S13 11 #define S14 19 #define S21 3 #define S22 5 #define S23 9 #define S24 13 #define S31 3 #define S32 9 #define S33 11 #define S34 15 /* F, G and H are basic LTC_MD4 functions. */ #define F(x, y, z) (z ^ (x & (y ^ z))) #define G(x, y, z) ((x & y) | (z & (x | y))) #define H(x, y, z) ((x) ^ (y) ^ (z)) /* ROTATE_LEFT rotates x left n bits. */ #define ROTATE_LEFT(x, n) ROLc(x, n) /* FF, GG and HH are transformations for rounds 1, 2 and 3 */ /* Rotation is separate from addition to prevent recomputation */ #define FF(a, b, c, d, x, s) { \ (a) += F ((b), (c), (d)) + (x); \ (a) = ROTATE_LEFT ((a), (s)); \ } #define GG(a, b, c, d, x, s) { \ (a) += G ((b), (c), (d)) + (x) + 0x5a827999UL; \ (a) = ROTATE_LEFT ((a), (s)); \ } #define HH(a, b, c, d, x, s) { \ (a) += H ((b), (c), (d)) + (x) + 0x6ed9eba1UL; \ (a) = ROTATE_LEFT ((a), (s)); \ } #ifdef LTC_CLEAN_STACK static int _md4_compress(hash_state *md, unsigned char *buf) #else static int md4_compress(hash_state *md, unsigned char *buf) #endif { ulong32 x[16], a, b, c, d; int i; /* copy state */ a = md->md4.state[0]; b = md->md4.state[1]; c = md->md4.state[2]; d = md->md4.state[3]; /* copy the state into 512-bits into W[0..15] */ for (i = 0; i < 16; i++) { LOAD32L(x[i], buf + (4*i)); } /* Round 1 */ FF (a, b, c, d, x[ 0], S11); /* 1 */ FF (d, a, b, c, x[ 1], S12); /* 2 */ FF (c, d, a, b, x[ 2], S13); /* 3 */ FF (b, c, d, a, x[ 3], S14); /* 4 */ FF (a, b, c, d, x[ 4], S11); /* 5 */ FF (d, a, b, c, x[ 5], S12); /* 6 */ FF (c, d, a, b, x[ 6], S13); /* 7 */ FF (b, c, d, a, x[ 7], S14); /* 8 */ FF (a, b, c, d, x[ 8], S11); /* 9 */ FF (d, a, b, c, x[ 9], S12); /* 10 */ FF (c, d, a, b, x[10], S13); /* 11 */ FF (b, c, d, a, x[11], S14); /* 12 */ FF (a, b, c, d, x[12], S11); /* 13 */ FF (d, a, b, c, x[13], S12); /* 14 */ FF (c, d, a, b, x[14], S13); /* 15 */ FF (b, c, d, a, x[15], S14); /* 16 */ /* Round 2 */ GG (a, b, c, d, x[ 0], S21); /* 17 */ GG (d, a, b, c, x[ 4], S22); /* 18 */ GG (c, d, a, b, x[ 8], S23); /* 19 */ GG (b, c, d, a, x[12], S24); /* 20 */ GG (a, b, c, d, x[ 1], S21); /* 21 */ GG (d, a, b, c, x[ 5], S22); /* 22 */ GG (c, d, a, b, x[ 9], S23); /* 23 */ GG (b, c, d, a, x[13], S24); /* 24 */ GG (a, b, c, d, x[ 2], S21); /* 25 */ GG (d, a, b, c, x[ 6], S22); /* 26 */ GG (c, d, a, b, x[10], S23); /* 27 */ GG (b, c, d, a, x[14], S24); /* 28 */ GG (a, b, c, d, x[ 3], S21); /* 29 */ GG (d, a, b, c, x[ 7], S22); /* 30 */ GG (c, d, a, b, x[11], S23); /* 31 */ GG (b, c, d, a, x[15], S24); /* 32 */ /* Round 3 */ HH (a, b, c, d, x[ 0], S31); /* 33 */ HH (d, a, b, c, x[ 8], S32); /* 34 */ HH (c, d, a, b, x[ 4], S33); /* 35 */ HH (b, c, d, a, x[12], S34); /* 36 */ HH (a, b, c, d, x[ 2], S31); /* 37 */ HH (d, a, b, c, x[10], S32); /* 38 */ HH (c, d, a, b, x[ 6], S33); /* 39 */ HH (b, c, d, a, x[14], S34); /* 40 */ HH (a, b, c, d, x[ 1], S31); /* 41 */ HH (d, a, b, c, x[ 9], S32); /* 42 */ HH (c, d, a, b, x[ 5], S33); /* 43 */ HH (b, c, d, a, x[13], S34); /* 44 */ HH (a, b, c, d, x[ 3], S31); /* 45 */ HH (d, a, b, c, x[11], S32); /* 46 */ HH (c, d, a, b, x[ 7], S33); /* 47 */ HH (b, c, d, a, x[15], S34); /* 48 */ /* Update our state */ md->md4.state[0] = md->md4.state[0] + a; md->md4.state[1] = md->md4.state[1] + b; md->md4.state[2] = md->md4.state[2] + c; md->md4.state[3] = md->md4.state[3] + d; return CRYPT_OK; } #ifdef LTC_CLEAN_STACK static int md4_compress(hash_state *md, unsigned char *buf) { int err; err = _md4_compress(md, buf); burn_stack(sizeof(ulong32) * 20 + sizeof(int)); return err; } #endif /** Initialize the hash state @param md The hash state you wish to initialize @return CRYPT_OK if successful */ int md4_init(hash_state * md) { LTC_ARGCHK(md != NULL); md->md4.state[0] = 0x67452301UL; md->md4.state[1] = 0xefcdab89UL; md->md4.state[2] = 0x98badcfeUL; md->md4.state[3] = 0x10325476UL; md->md4.length = 0; md->md4.curlen = 0; return CRYPT_OK; } /** Process a block of memory though the hash @param md The hash state @param in The data to hash @param inlen The length of the data (octets) @return CRYPT_OK if successful */ HASH_PROCESS(md4_process, md4_compress, md4, 64) /** Terminate the hash to get the digest @param md The hash state @param out [out] The destination of the hash (16 bytes) @return CRYPT_OK if successful */ int md4_done(hash_state * md, unsigned char *out) { int i; LTC_ARGCHK(md != NULL); LTC_ARGCHK(out != NULL); if (md->md4.curlen >= sizeof(md->md4.buf)) { return CRYPT_INVALID_ARG; } /* increase the length of the message */ md->md4.length += md->md4.curlen * 8; /* append the '1' bit */ md->md4.buf[md->md4.curlen++] = (unsigned char)0x80; /* if the length is currently above 56 bytes we append zeros * then compress. Then we can fall back to padding zeros and length * encoding like normal. */ if (md->md4.curlen > 56) { while (md->md4.curlen < 64) { md->md4.buf[md->md4.curlen++] = (unsigned char)0; } md4_compress(md, md->md4.buf); md->md4.curlen = 0; } /* pad upto 56 bytes of zeroes */ while (md->md4.curlen < 56) { md->md4.buf[md->md4.curlen++] = (unsigned char)0; } /* store length */ STORE64L(md->md4.length, md->md4.buf+56); md4_compress(md, md->md4.buf); /* copy output */ for (i = 0; i < 4; i++) { STORE32L(md->md4.state[i], out+(4*i)); } #ifdef LTC_CLEAN_STACK zeromem(md, sizeof(hash_state)); #endif return CRYPT_OK; } /** Self-test the hash @return CRYPT_OK if successful, CRYPT_NOP if self-tests have been disabled */ int md4_test(void) { #ifndef LTC_TEST return CRYPT_NOP; #else static const struct md4_test_case { const char *input; unsigned char hash[16]; } tests[] = { { "", {0x31, 0xd6, 0xcf, 0xe0, 0xd1, 0x6a, 0xe9, 0x31, 0xb7, 0x3c, 0x59, 0xd7, 0xe0, 0xc0, 0x89, 0xc0} }, { "a", {0xbd, 0xe5, 0x2c, 0xb3, 0x1d, 0xe3, 0x3e, 0x46, 0x24, 0x5e, 0x05, 0xfb, 0xdb, 0xd6, 0xfb, 0x24} }, { "abc", {0xa4, 0x48, 0x01, 0x7a, 0xaf, 0x21, 0xd8, 0x52, 0x5f, 0xc1, 0x0a, 0xe8, 0x7a, 0xa6, 0x72, 0x9d} }, { "message digest", {0xd9, 0x13, 0x0a, 0x81, 0x64, 0x54, 0x9f, 0xe8, 0x18, 0x87, 0x48, 0x06, 0xe1, 0xc7, 0x01, 0x4b} }, { "abcdefghijklmnopqrstuvwxyz", {0xd7, 0x9e, 0x1c, 0x30, 0x8a, 0xa5, 0xbb, 0xcd, 0xee, 0xa8, 0xed, 0x63, 0xdf, 0x41, 0x2d, 0xa9} }, { "ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz0123456789", {0x04, 0x3f, 0x85, 0x82, 0xf2, 0x41, 0xdb, 0x35, 0x1c, 0xe6, 0x27, 0xe1, 0x53, 0xe7, 0xf0, 0xe4} }, { "12345678901234567890123456789012345678901234567890123456789012345678901234567890", {0xe3, 0x3b, 0x4d, 0xdc, 0x9c, 0x38, 0xf2, 0x19, 0x9c, 0x3e, 0x7b, 0x16, 0x4f, 0xcc, 0x05, 0x36} }, }; int i; unsigned char tmp[16]; hash_state md; for(i = 0; i < (int)(sizeof(tests) / sizeof(tests[0])); i++) { md4_init(&md); md4_process(&md, (unsigned char *)tests[i].input, (unsigned long)strlen(tests[i].input)); md4_done(&md, tmp); if (compare_testvector(tmp, sizeof(tmp), tests[i].hash, sizeof(tests[i].hash), "MD4", i)) { return CRYPT_FAIL_TESTVECTOR; } } return CRYPT_OK; #endif } #endif /* ref: $Format:%D$ */ /* git commit: $Format:%H$ */ /* commit time: $Format:%ai$ */