annotate libtomcrypt/src/pk/asn1/der/teletex_string/der_decode_teletex_string.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
Ignore whitespace changes - Everywhere: Within whitespace: At end of lines:
rev   line source
1471
6dba84798cd5 Update to libtomcrypt 1.18.1, merged with Dropbear changes
Matt Johnston <matt@ucc.asn.au>
parents:
diff changeset
1 /* LibTomCrypt, modular cryptographic library -- Tom St Denis
6dba84798cd5 Update to libtomcrypt 1.18.1, merged with Dropbear changes
Matt Johnston <matt@ucc.asn.au>
parents:
diff changeset
2 *
6dba84798cd5 Update to libtomcrypt 1.18.1, merged with Dropbear changes
Matt Johnston <matt@ucc.asn.au>
parents:
diff changeset
3 * LibTomCrypt is a library that provides various cryptographic
6dba84798cd5 Update to libtomcrypt 1.18.1, merged with Dropbear changes
Matt Johnston <matt@ucc.asn.au>
parents:
diff changeset
4 * algorithms in a highly modular and flexible manner.
6dba84798cd5 Update to libtomcrypt 1.18.1, merged with Dropbear changes
Matt Johnston <matt@ucc.asn.au>
parents:
diff changeset
5 *
6dba84798cd5 Update to libtomcrypt 1.18.1, merged with Dropbear changes
Matt Johnston <matt@ucc.asn.au>
parents:
diff changeset
6 * The library is free for all purposes without any express
6dba84798cd5 Update to libtomcrypt 1.18.1, merged with Dropbear changes
Matt Johnston <matt@ucc.asn.au>
parents:
diff changeset
7 * guarantee it works.
6dba84798cd5 Update to libtomcrypt 1.18.1, merged with Dropbear changes
Matt Johnston <matt@ucc.asn.au>
parents:
diff changeset
8 */
6dba84798cd5 Update to libtomcrypt 1.18.1, merged with Dropbear changes
Matt Johnston <matt@ucc.asn.au>
parents:
diff changeset
9 #include "tomcrypt.h"
6dba84798cd5 Update to libtomcrypt 1.18.1, merged with Dropbear changes
Matt Johnston <matt@ucc.asn.au>
parents:
diff changeset
10
6dba84798cd5 Update to libtomcrypt 1.18.1, merged with Dropbear changes
Matt Johnston <matt@ucc.asn.au>
parents:
diff changeset
11 /**
6dba84798cd5 Update to libtomcrypt 1.18.1, merged with Dropbear changes
Matt Johnston <matt@ucc.asn.au>
parents:
diff changeset
12 @file der_decode_teletex_string.c
6dba84798cd5 Update to libtomcrypt 1.18.1, merged with Dropbear changes
Matt Johnston <matt@ucc.asn.au>
parents:
diff changeset
13 ASN.1 DER, encode a teletex STRING
6dba84798cd5 Update to libtomcrypt 1.18.1, merged with Dropbear changes
Matt Johnston <matt@ucc.asn.au>
parents:
diff changeset
14 */
6dba84798cd5 Update to libtomcrypt 1.18.1, merged with Dropbear changes
Matt Johnston <matt@ucc.asn.au>
parents:
diff changeset
15
6dba84798cd5 Update to libtomcrypt 1.18.1, merged with Dropbear changes
Matt Johnston <matt@ucc.asn.au>
parents:
diff changeset
16 #ifdef LTC_DER
6dba84798cd5 Update to libtomcrypt 1.18.1, merged with Dropbear changes
Matt Johnston <matt@ucc.asn.au>
parents:
diff changeset
17
6dba84798cd5 Update to libtomcrypt 1.18.1, merged with Dropbear changes
Matt Johnston <matt@ucc.asn.au>
parents:
diff changeset
18 /**
6dba84798cd5 Update to libtomcrypt 1.18.1, merged with Dropbear changes
Matt Johnston <matt@ucc.asn.au>
parents:
diff changeset
19 Store a teletex STRING
6dba84798cd5 Update to libtomcrypt 1.18.1, merged with Dropbear changes
Matt Johnston <matt@ucc.asn.au>
parents:
diff changeset
20 @param in The DER encoded teletex STRING
6dba84798cd5 Update to libtomcrypt 1.18.1, merged with Dropbear changes
Matt Johnston <matt@ucc.asn.au>
parents:
diff changeset
21 @param inlen The size of the DER teletex STRING
6dba84798cd5 Update to libtomcrypt 1.18.1, merged with Dropbear changes
Matt Johnston <matt@ucc.asn.au>
parents:
diff changeset
22 @param out [out] The array of octets stored (one per char)
6dba84798cd5 Update to libtomcrypt 1.18.1, merged with Dropbear changes
Matt Johnston <matt@ucc.asn.au>
parents:
diff changeset
23 @param outlen [in/out] The number of octets stored
6dba84798cd5 Update to libtomcrypt 1.18.1, merged with Dropbear changes
Matt Johnston <matt@ucc.asn.au>
parents:
diff changeset
24 @return CRYPT_OK if successful
6dba84798cd5 Update to libtomcrypt 1.18.1, merged with Dropbear changes
Matt Johnston <matt@ucc.asn.au>
parents:
diff changeset
25 */
6dba84798cd5 Update to libtomcrypt 1.18.1, merged with Dropbear changes
Matt Johnston <matt@ucc.asn.au>
parents:
diff changeset
26 int der_decode_teletex_string(const unsigned char *in, unsigned long inlen,
6dba84798cd5 Update to libtomcrypt 1.18.1, merged with Dropbear changes
Matt Johnston <matt@ucc.asn.au>
parents:
diff changeset
27 unsigned char *out, unsigned long *outlen)
6dba84798cd5 Update to libtomcrypt 1.18.1, merged with Dropbear changes
Matt Johnston <matt@ucc.asn.au>
parents:
diff changeset
28 {
6dba84798cd5 Update to libtomcrypt 1.18.1, merged with Dropbear changes
Matt Johnston <matt@ucc.asn.au>
parents:
diff changeset
29 unsigned long x, y, len;
6dba84798cd5 Update to libtomcrypt 1.18.1, merged with Dropbear changes
Matt Johnston <matt@ucc.asn.au>
parents:
diff changeset
30 int t;
6dba84798cd5 Update to libtomcrypt 1.18.1, merged with Dropbear changes
Matt Johnston <matt@ucc.asn.au>
parents:
diff changeset
31
6dba84798cd5 Update to libtomcrypt 1.18.1, merged with Dropbear changes
Matt Johnston <matt@ucc.asn.au>
parents:
diff changeset
32 LTC_ARGCHK(in != NULL);
6dba84798cd5 Update to libtomcrypt 1.18.1, merged with Dropbear changes
Matt Johnston <matt@ucc.asn.au>
parents:
diff changeset
33 LTC_ARGCHK(out != NULL);
6dba84798cd5 Update to libtomcrypt 1.18.1, merged with Dropbear changes
Matt Johnston <matt@ucc.asn.au>
parents:
diff changeset
34 LTC_ARGCHK(outlen != NULL);
6dba84798cd5 Update to libtomcrypt 1.18.1, merged with Dropbear changes
Matt Johnston <matt@ucc.asn.au>
parents:
diff changeset
35
6dba84798cd5 Update to libtomcrypt 1.18.1, merged with Dropbear changes
Matt Johnston <matt@ucc.asn.au>
parents:
diff changeset
36 /* must have header at least */
6dba84798cd5 Update to libtomcrypt 1.18.1, merged with Dropbear changes
Matt Johnston <matt@ucc.asn.au>
parents:
diff changeset
37 if (inlen < 2) {
6dba84798cd5 Update to libtomcrypt 1.18.1, merged with Dropbear changes
Matt Johnston <matt@ucc.asn.au>
parents:
diff changeset
38 return CRYPT_INVALID_PACKET;
6dba84798cd5 Update to libtomcrypt 1.18.1, merged with Dropbear changes
Matt Johnston <matt@ucc.asn.au>
parents:
diff changeset
39 }
6dba84798cd5 Update to libtomcrypt 1.18.1, merged with Dropbear changes
Matt Johnston <matt@ucc.asn.au>
parents:
diff changeset
40
6dba84798cd5 Update to libtomcrypt 1.18.1, merged with Dropbear changes
Matt Johnston <matt@ucc.asn.au>
parents:
diff changeset
41 /* check for 0x14 */
6dba84798cd5 Update to libtomcrypt 1.18.1, merged with Dropbear changes
Matt Johnston <matt@ucc.asn.au>
parents:
diff changeset
42 if ((in[0] & 0x1F) != 0x14) {
6dba84798cd5 Update to libtomcrypt 1.18.1, merged with Dropbear changes
Matt Johnston <matt@ucc.asn.au>
parents:
diff changeset
43 return CRYPT_INVALID_PACKET;
6dba84798cd5 Update to libtomcrypt 1.18.1, merged with Dropbear changes
Matt Johnston <matt@ucc.asn.au>
parents:
diff changeset
44 }
6dba84798cd5 Update to libtomcrypt 1.18.1, merged with Dropbear changes
Matt Johnston <matt@ucc.asn.au>
parents:
diff changeset
45 x = 1;
6dba84798cd5 Update to libtomcrypt 1.18.1, merged with Dropbear changes
Matt Johnston <matt@ucc.asn.au>
parents:
diff changeset
46
6dba84798cd5 Update to libtomcrypt 1.18.1, merged with Dropbear changes
Matt Johnston <matt@ucc.asn.au>
parents:
diff changeset
47 /* decode the length */
6dba84798cd5 Update to libtomcrypt 1.18.1, merged with Dropbear changes
Matt Johnston <matt@ucc.asn.au>
parents:
diff changeset
48 if (in[x] & 0x80) {
6dba84798cd5 Update to libtomcrypt 1.18.1, merged with Dropbear changes
Matt Johnston <matt@ucc.asn.au>
parents:
diff changeset
49 /* valid # of bytes in length are 1,2,3 */
6dba84798cd5 Update to libtomcrypt 1.18.1, merged with Dropbear changes
Matt Johnston <matt@ucc.asn.au>
parents:
diff changeset
50 y = in[x] & 0x7F;
6dba84798cd5 Update to libtomcrypt 1.18.1, merged with Dropbear changes
Matt Johnston <matt@ucc.asn.au>
parents:
diff changeset
51 if ((y == 0) || (y > 3) || ((x + y) > inlen)) {
6dba84798cd5 Update to libtomcrypt 1.18.1, merged with Dropbear changes
Matt Johnston <matt@ucc.asn.au>
parents:
diff changeset
52 return CRYPT_INVALID_PACKET;
6dba84798cd5 Update to libtomcrypt 1.18.1, merged with Dropbear changes
Matt Johnston <matt@ucc.asn.au>
parents:
diff changeset
53 }
6dba84798cd5 Update to libtomcrypt 1.18.1, merged with Dropbear changes
Matt Johnston <matt@ucc.asn.au>
parents:
diff changeset
54
6dba84798cd5 Update to libtomcrypt 1.18.1, merged with Dropbear changes
Matt Johnston <matt@ucc.asn.au>
parents:
diff changeset
55 /* read the length in */
6dba84798cd5 Update to libtomcrypt 1.18.1, merged with Dropbear changes
Matt Johnston <matt@ucc.asn.au>
parents:
diff changeset
56 len = 0;
6dba84798cd5 Update to libtomcrypt 1.18.1, merged with Dropbear changes
Matt Johnston <matt@ucc.asn.au>
parents:
diff changeset
57 ++x;
6dba84798cd5 Update to libtomcrypt 1.18.1, merged with Dropbear changes
Matt Johnston <matt@ucc.asn.au>
parents:
diff changeset
58 while (y--) {
6dba84798cd5 Update to libtomcrypt 1.18.1, merged with Dropbear changes
Matt Johnston <matt@ucc.asn.au>
parents:
diff changeset
59 len = (len << 8) | in[x++];
6dba84798cd5 Update to libtomcrypt 1.18.1, merged with Dropbear changes
Matt Johnston <matt@ucc.asn.au>
parents:
diff changeset
60 }
6dba84798cd5 Update to libtomcrypt 1.18.1, merged with Dropbear changes
Matt Johnston <matt@ucc.asn.au>
parents:
diff changeset
61 } else {
6dba84798cd5 Update to libtomcrypt 1.18.1, merged with Dropbear changes
Matt Johnston <matt@ucc.asn.au>
parents:
diff changeset
62 len = in[x++] & 0x7F;
6dba84798cd5 Update to libtomcrypt 1.18.1, merged with Dropbear changes
Matt Johnston <matt@ucc.asn.au>
parents:
diff changeset
63 }
6dba84798cd5 Update to libtomcrypt 1.18.1, merged with Dropbear changes
Matt Johnston <matt@ucc.asn.au>
parents:
diff changeset
64
6dba84798cd5 Update to libtomcrypt 1.18.1, merged with Dropbear changes
Matt Johnston <matt@ucc.asn.au>
parents:
diff changeset
65 /* is it too long? */
6dba84798cd5 Update to libtomcrypt 1.18.1, merged with Dropbear changes
Matt Johnston <matt@ucc.asn.au>
parents:
diff changeset
66 if (len > *outlen) {
6dba84798cd5 Update to libtomcrypt 1.18.1, merged with Dropbear changes
Matt Johnston <matt@ucc.asn.au>
parents:
diff changeset
67 *outlen = len;
6dba84798cd5 Update to libtomcrypt 1.18.1, merged with Dropbear changes
Matt Johnston <matt@ucc.asn.au>
parents:
diff changeset
68 return CRYPT_BUFFER_OVERFLOW;
6dba84798cd5 Update to libtomcrypt 1.18.1, merged with Dropbear changes
Matt Johnston <matt@ucc.asn.au>
parents:
diff changeset
69 }
6dba84798cd5 Update to libtomcrypt 1.18.1, merged with Dropbear changes
Matt Johnston <matt@ucc.asn.au>
parents:
diff changeset
70
6dba84798cd5 Update to libtomcrypt 1.18.1, merged with Dropbear changes
Matt Johnston <matt@ucc.asn.au>
parents:
diff changeset
71 if (len + x > inlen) {
6dba84798cd5 Update to libtomcrypt 1.18.1, merged with Dropbear changes
Matt Johnston <matt@ucc.asn.au>
parents:
diff changeset
72 return CRYPT_INVALID_PACKET;
6dba84798cd5 Update to libtomcrypt 1.18.1, merged with Dropbear changes
Matt Johnston <matt@ucc.asn.au>
parents:
diff changeset
73 }
6dba84798cd5 Update to libtomcrypt 1.18.1, merged with Dropbear changes
Matt Johnston <matt@ucc.asn.au>
parents:
diff changeset
74
6dba84798cd5 Update to libtomcrypt 1.18.1, merged with Dropbear changes
Matt Johnston <matt@ucc.asn.au>
parents:
diff changeset
75 /* read the data */
6dba84798cd5 Update to libtomcrypt 1.18.1, merged with Dropbear changes
Matt Johnston <matt@ucc.asn.au>
parents:
diff changeset
76 for (y = 0; y < len; y++) {
6dba84798cd5 Update to libtomcrypt 1.18.1, merged with Dropbear changes
Matt Johnston <matt@ucc.asn.au>
parents:
diff changeset
77 t = der_teletex_value_decode(in[x++]);
6dba84798cd5 Update to libtomcrypt 1.18.1, merged with Dropbear changes
Matt Johnston <matt@ucc.asn.au>
parents:
diff changeset
78 if (t == -1) {
6dba84798cd5 Update to libtomcrypt 1.18.1, merged with Dropbear changes
Matt Johnston <matt@ucc.asn.au>
parents:
diff changeset
79 return CRYPT_INVALID_ARG;
6dba84798cd5 Update to libtomcrypt 1.18.1, merged with Dropbear changes
Matt Johnston <matt@ucc.asn.au>
parents:
diff changeset
80 }
6dba84798cd5 Update to libtomcrypt 1.18.1, merged with Dropbear changes
Matt Johnston <matt@ucc.asn.au>
parents:
diff changeset
81 out[y] = t;
6dba84798cd5 Update to libtomcrypt 1.18.1, merged with Dropbear changes
Matt Johnston <matt@ucc.asn.au>
parents:
diff changeset
82 }
6dba84798cd5 Update to libtomcrypt 1.18.1, merged with Dropbear changes
Matt Johnston <matt@ucc.asn.au>
parents:
diff changeset
83
6dba84798cd5 Update to libtomcrypt 1.18.1, merged with Dropbear changes
Matt Johnston <matt@ucc.asn.au>
parents:
diff changeset
84 *outlen = y;
6dba84798cd5 Update to libtomcrypt 1.18.1, merged with Dropbear changes
Matt Johnston <matt@ucc.asn.au>
parents:
diff changeset
85
6dba84798cd5 Update to libtomcrypt 1.18.1, merged with Dropbear changes
Matt Johnston <matt@ucc.asn.au>
parents:
diff changeset
86 return CRYPT_OK;
6dba84798cd5 Update to libtomcrypt 1.18.1, merged with Dropbear changes
Matt Johnston <matt@ucc.asn.au>
parents:
diff changeset
87 }
6dba84798cd5 Update to libtomcrypt 1.18.1, merged with Dropbear changes
Matt Johnston <matt@ucc.asn.au>
parents:
diff changeset
88
6dba84798cd5 Update to libtomcrypt 1.18.1, merged with Dropbear changes
Matt Johnston <matt@ucc.asn.au>
parents:
diff changeset
89 #endif
6dba84798cd5 Update to libtomcrypt 1.18.1, merged with Dropbear changes
Matt Johnston <matt@ucc.asn.au>
parents:
diff changeset
90
6dba84798cd5 Update to libtomcrypt 1.18.1, merged with Dropbear changes
Matt Johnston <matt@ucc.asn.au>
parents:
diff changeset
91 /* ref: $Format:%D$ */
6dba84798cd5 Update to libtomcrypt 1.18.1, merged with Dropbear changes
Matt Johnston <matt@ucc.asn.au>
parents:
diff changeset
92 /* git commit: $Format:%H$ */
6dba84798cd5 Update to libtomcrypt 1.18.1, merged with Dropbear changes
Matt Johnston <matt@ucc.asn.au>
parents:
diff changeset
93 /* commit time: $Format:%ai$ */