diff options
Diffstat (limited to 'plugins/MirOTR/libotr/src/b64.c')
| -rw-r--r-- | plugins/MirOTR/libotr/src/b64.c | 86 |
1 files changed, 52 insertions, 34 deletions
diff --git a/plugins/MirOTR/libotr/src/b64.c b/plugins/MirOTR/libotr/src/b64.c index 222f56634c..a7d53aa2b1 100644 --- a/plugins/MirOTR/libotr/src/b64.c +++ b/plugins/MirOTR/libotr/src/b64.c @@ -1,6 +1,7 @@ /* * Off-the-Record Messaging library - * Copyright (C) 2004-2008 Ian Goldberg, Chris Alexander, Nikita Borisov + * Copyright (C) 2004-2012 Ian Goldberg, Chris Alexander, Willy Lew, + * Nikita Borisov * <otr@cypherpunks.ca> * * This library is free software; you can redistribute it and/or @@ -14,7 +15,7 @@ * * You should have received a copy of the GNU Lesser General Public * License along with this library; if not, write to the Free Software - * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA + * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA */ /* Modified from: */ @@ -27,35 +28,35 @@ AUTHOR: Bob Trower 08/04/01 LICENCE: Copyright (c) 2001 Bob Trower, Trantor Standard Systems Inc. - Permission is hereby granted, free of charge, to any person - obtaining a copy of this software and associated - documentation files (the "Software"), to deal in the - Software without restriction, including without limitation - the rights to use, copy, modify, merge, publish, distribute, - sublicense, and/or sell copies of the Software, and to - permit persons to whom the Software is furnished to do so, - subject to the following conditions: - - The above copyright notice and this permission notice shall - be included in all copies or substantial portions of the - Software. - - THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY - KIND, EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE - WARRANTIES OF MERCHANTABILITY, FITNESS FOR A PARTICULAR - PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS - OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR - OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR - OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE - SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE. + Permission is hereby granted, free of charge, to any person + obtaining a copy of this software and associated + documentation files (the "Software"), to deal in the + Software without restriction, including without limitation + the rights to use, copy, modify, merge, publish, distribute, + sublicense, and/or sell copies of the Software, and to + permit persons to whom the Software is furnished to do so, + subject to the following conditions: + + The above copyright notice and this permission notice shall + be included in all copies or substantial portions of the + Software. + + THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY + KIND, EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE + WARRANTIES OF MERCHANTABILITY, FITNESS FOR A PARTICULAR + PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS + OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR + OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR + OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE + SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE. VERSION HISTORY: - Bob Trower 08/04/01 -- Create Version 0.00.00B + Bob Trower 08/04/01 -- Create Version 0.00.00B \******************************************************************* */ /* system headers */ -#include <stdlib.h> +#include <stdio.h> #include <string.h> /* libotr headers */ @@ -87,9 +88,9 @@ static void encodeblock( char *out, const unsigned char *in, size_t len ) out[0] = cb64[ in0 >> 2 ]; out[1] = cb64[ ((in0 & 0x03) << 4) | ((in1 & 0xf0) >> 4) ]; out[2] = len > 1 ? cb64[ ((in1 & 0x0f) << 2) | ((in2 & 0xc0) >> 6) ] - : '='; + : '='; out[3] = len > 2 ? cb64[ in2 & 0x3f ] - : '='; + : '='; } /* @@ -119,7 +120,7 @@ size_t otrl_base64_encode(char *base64data, const unsigned char *data, } static size_t decode(unsigned char *out, const char *in, size_t b64len) -{ +{ size_t written = 0; unsigned char c = 0; @@ -147,8 +148,9 @@ static size_t decode(unsigned char *out, const char *in, size_t b64len) * base64 decode data. Skip non-base64 chars, and terminate at the * first '=', or the end of the buffer. * - * The buffer data must contain at least (base64len / 4) * 3 bytes of - * space. This function will return the number of bytes actually used. + * The buffer data must contain at least ((base64len+3) / 4) * 3 bytes + * of space. This function will return the number of bytes actually + * used. */ size_t otrl_base64_decode(unsigned char *data, const char *base64data, size_t base64len) @@ -195,6 +197,16 @@ char *otrl_base64_otr_encode(const unsigned char *buf, size_t buflen) { char *base64buf; size_t base64len; + const size_t HALF_MAX_SIZE_T = ((size_t)-1) >> 1; + + if (buflen > HALF_MAX_SIZE_T) { + /* You somehow have a buffer that's of size more than half of + * all addressable memory, and you now want a base64 version in + * a new buffer 33% larger? Not going to happen. Exit now, + * rather in the malloc below, to avoid integer overflowing the + * computation of base64len. */ + return NULL; + } /* Make the base64-encoding. */ base64len = ((buflen + 2) / 3) * 4; @@ -202,7 +214,7 @@ char *otrl_base64_otr_encode(const unsigned char *buf, size_t buflen) if (base64buf == NULL) { return NULL; } - memcpy(base64buf, "?OTR:", 5); + memmove(base64buf, "?OTR:", 5); otrl_base64_encode(base64buf+5, buf, buflen); base64buf[5 + base64len] = '.'; base64buf[5 + base64len + 1] = '\0'; @@ -227,20 +239,26 @@ int otrl_base64_otr_decode(const char *msg, unsigned char **bufp, if (!otrtag) { return -2; } + endtag = strchr(otrtag, '.'); if (endtag) { - msglen = endtag-otrtag; + msglen = endtag-otrtag; } else { return -2; } + /* Skip over the "?OTR:" */ + otrtag += 5; + msglen -= 5; + /* Base64-decode the message */ - rawlen = ((msglen-5) / 4) * 3; /* maximum possible */ + rawlen = OTRL_B64_MAX_DECODED_SIZE(msglen); /* maximum possible */ rawmsg = malloc(rawlen); if (!rawmsg && rawlen > 0) { return -1; } - rawlen = otrl_base64_decode(rawmsg, otrtag+5, msglen-5); /* actual size */ + + rawlen = otrl_base64_decode(rawmsg, otrtag, msglen); /* actual size */ *bufp = rawmsg; *lenp = rawlen; |