diff options
Diffstat (limited to 'plugins/sudoers/b64_decode.c')
-rw-r--r-- | plugins/sudoers/b64_decode.c | 83 |
1 files changed, 83 insertions, 0 deletions
diff --git a/plugins/sudoers/b64_decode.c b/plugins/sudoers/b64_decode.c new file mode 100644 index 0000000..736df28 --- /dev/null +++ b/plugins/sudoers/b64_decode.c @@ -0,0 +1,83 @@ +/* + * SPDX-License-Identifier: ISC + * + * Copyright (c) 2013-2018 Todd C. Miller <Todd.Miller@sudo.ws> + * + * Permission to use, copy, modify, and distribute this software for any + * purpose with or without fee is hereby granted, provided that the above + * copyright notice and this permission notice appear in all copies. + * + * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES + * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF + * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR + * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES + * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN + * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF + * OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE. + */ + +/* + * This is an open source non-commercial project. Dear PVS-Studio, please check it. + * PVS-Studio Static Code Analyzer for C, C++ and C#: http://www.viva64.com + */ + +#include <config.h> + +#include "sudoers.h" + +/* + * Derived from code with the following declaration: + * PUBLIC DOMAIN - Jon Mayo - November 13, 2003 + */ + +static const unsigned char base64dec_tab[256]= { + 255,255,255,255,255,255,255,255,255,255,255,255,255,255,255,255, + 255,255,255,255,255,255,255,255,255,255,255,255,255,255,255,255, + 255,255,255,255,255,255,255,255,255,255,255, 62,255,255,255, 63, + 52, 53, 54, 55, 56, 57, 58, 59, 60, 61,255,255,255, 0,255,255, + 255, 0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, + 15, 16, 17, 18, 19, 20, 21, 22, 23, 24, 25,255,255,255,255,255, + 255, 26, 27, 28, 29, 30, 31, 32, 33, 34, 35, 36, 37, 38, 39, 40, + 41, 42, 43, 44, 45, 46, 47, 48, 49, 50, 51,255,255,255,255,255, + 255,255,255,255,255,255,255,255,255,255,255,255,255,255,255,255, + 255,255,255,255,255,255,255,255,255,255,255,255,255,255,255,255, + 255,255,255,255,255,255,255,255,255,255,255,255,255,255,255,255, + 255,255,255,255,255,255,255,255,255,255,255,255,255,255,255,255, + 255,255,255,255,255,255,255,255,255,255,255,255,255,255,255,255, + 255,255,255,255,255,255,255,255,255,255,255,255,255,255,255,255, + 255,255,255,255,255,255,255,255,255,255,255,255,255,255,255,255, + 255,255,255,255,255,255,255,255,255,255,255,255,255,255,255,255, +}; + +/* + * Decode a NUL-terminated string in base64 format and store the + * result in dst. + */ +size_t +base64_decode(const char *in, unsigned char *out, size_t out_size) +{ + unsigned char *out_end = out + out_size; + const unsigned char *out0 = out; + unsigned int rem, v; + debug_decl(base64_decode, SUDOERS_DEBUG_MATCH); + + for (v = 0, rem = 0; *in != '\0' && *in != '='; in++) { + unsigned char ch = base64dec_tab[(unsigned char)*in]; + if (ch == 255) + debug_return_size_t((size_t)-1); + v = (v << 6) | ch; + rem += 6; + if (rem >= 8) { + rem -= 8; + if (out >= out_end) + debug_return_size_t((size_t)-1); + *out++ = (v >> rem) & 0xff; + } + } + if (rem >= 8) { + if (out >= out_end) + debug_return_size_t((size_t)-1); + *out++ = (v >> rem) & 0xff; + } + debug_return_size_t((size_t)(out - out0)); +} |