diff options
Diffstat (limited to 'thirdparty/libwebsockets/lib/misc/base64-decode.c')
-rw-r--r-- | thirdparty/libwebsockets/lib/misc/base64-decode.c | 241 |
1 files changed, 241 insertions, 0 deletions
diff --git a/thirdparty/libwebsockets/lib/misc/base64-decode.c b/thirdparty/libwebsockets/lib/misc/base64-decode.c new file mode 100644 index 0000000000..de2efc8fd1 --- /dev/null +++ b/thirdparty/libwebsockets/lib/misc/base64-decode.c @@ -0,0 +1,241 @@ +/* + * This code originally came from here + * + * http://base64.sourceforge.net/b64.c + * + * with the following license: + * + * 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. + * + * VERSION HISTORY: + * Bob Trower 08/04/01 -- Create Version 0.00.00B + * + * I cleaned it up quite a bit to match the (linux kernel) style of the rest + * of libwebsockets; this version is under LGPL2.1 + SLE like the rest of lws + * since he explicitly allows sublicensing, but I give the URL above so you can + * get the original with Bob's super-liberal terms directly if you prefer. + */ + +#include <stdio.h> +#include <string.h> +#include "core/private.h" + +static const char encode_orig[] = "ABCDEFGHIJKLMNOPQRSTUVWXYZ" + "abcdefghijklmnopqrstuvwxyz0123456789+/"; +static const char encode_url[] = "ABCDEFGHIJKLMNOPQRSTUVWXYZ" + "abcdefghijklmnopqrstuvwxyz0123456789-_"; +static const char decode[] = "|$$$}rstuvwxyz{$$$$$$$>?@ABCDEFGHIJKLMNOPQRSTUVW" + "$$$$$$XYZ[\\]^_`abcdefghijklmnopq"; + +static int +_lws_b64_encode_string(const char *encode, const char *in, int in_len, + char *out, int out_size) +{ + unsigned char triple[3]; + int i; + int line = 0; + int done = 0; + + while (in_len) { + int len = 0; + for (i = 0; i < 3; i++) { + if (in_len) { + triple[i] = *in++; + len++; + in_len--; + } else + triple[i] = 0; + } + + if (done + 4 >= out_size) + return -1; + + *out++ = encode[triple[0] >> 2]; + *out++ = encode[((triple[0] & 0x03) << 4) | + ((triple[1] & 0xf0) >> 4)]; + *out++ = (len > 1 ? encode[((triple[1] & 0x0f) << 2) | + ((triple[2] & 0xc0) >> 6)] : '='); + *out++ = (len > 2 ? encode[triple[2] & 0x3f] : '='); + + done += 4; + line += 4; + } + + if (done + 1 >= out_size) + return -1; + + *out++ = '\0'; + + return done; +} + +LWS_VISIBLE int +lws_b64_encode_string(const char *in, int in_len, char *out, int out_size) +{ + return _lws_b64_encode_string(encode_orig, in, in_len, out, out_size); +} + +LWS_VISIBLE int +lws_b64_encode_string_url(const char *in, int in_len, char *out, int out_size) +{ + return _lws_b64_encode_string(encode_url, in, in_len, out, out_size); +} + +/* + * returns length of decoded string in out, or -1 if out was too small + * according to out_size + * + * Only reads up to in_len chars, otherwise if in_len is -1 on entry reads until + * the first NUL in the input. + */ + +static int +_lws_b64_decode_string(const char *in, int in_len, char *out, int out_size) +{ + int len, i, c = 0, done = 0; + unsigned char v, quad[4]; + + while (in_len && *in) { + + len = 0; + for (i = 0; i < 4 && in_len && *in; i++) { + + v = 0; + c = 0; + while (in_len && *in && !v) { + c = v = *in++; + in_len--; + /* support the url base64 variant too */ + if (v == '-') + c = v = '+'; + if (v == '_') + c = v = '/'; + v = (v < 43 || v > 122) ? 0 : decode[v - 43]; + if (v) + v = (v == '$') ? 0 : v - 61; + } + if (c) { + len++; + if (v) + quad[i] = v - 1; + } else + quad[i] = 0; + } + + if (out_size < (done + len - 1)) + /* out buffer is too small */ + return -1; + + /* + * "The '==' sequence indicates that the last group contained + * only one byte, and '=' indicates that it contained two + * bytes." (wikipedia) + */ + + if ((!in_len || !*in) && c == '=') + len--; + + if (len >= 2) + *out++ = quad[0] << 2 | quad[1] >> 4; + if (len >= 3) + *out++ = quad[1] << 4 | quad[2] >> 2; + if (len >= 4) + *out++ = ((quad[2] << 6) & 0xc0) | quad[3]; + + done += len - 1; + } + + if (done + 1 >= out_size) + return -1; + + *out = '\0'; + + return done; +} + +LWS_VISIBLE int +lws_b64_decode_string(const char *in, char *out, int out_size) +{ + return _lws_b64_decode_string(in, -1, out, out_size); +} + +LWS_VISIBLE int +lws_b64_decode_string_len(const char *in, int in_len, char *out, int out_size) +{ + return _lws_b64_decode_string(in, in_len, out, out_size); +} + +#if 0 +int +lws_b64_selftest(void) +{ + char buf[64]; + unsigned int n, r = 0; + unsigned int test; + /* examples from https://en.wikipedia.org/wiki/Base64 */ + static const char * const plaintext[] = { + "any carnal pleasure.", + "any carnal pleasure", + "any carnal pleasur", + "any carnal pleasu", + "any carnal pleas", + "Admin:kloikloi" + }; + static const char * const coded[] = { + "YW55IGNhcm5hbCBwbGVhc3VyZS4=", + "YW55IGNhcm5hbCBwbGVhc3VyZQ==", + "YW55IGNhcm5hbCBwbGVhc3Vy", + "YW55IGNhcm5hbCBwbGVhc3U=", + "YW55IGNhcm5hbCBwbGVhcw==", + "QWRtaW46a2xvaWtsb2k=" + }; + + for (test = 0; test < sizeof plaintext / sizeof(plaintext[0]); test++) { + + buf[sizeof(buf) - 1] = '\0'; + n = lws_b64_encode_string(plaintext[test], + strlen(plaintext[test]), buf, sizeof buf); + if (n != strlen(coded[test]) || strcmp(buf, coded[test])) { + lwsl_err("Failed lws_b64 encode selftest " + "%d result '%s' %d\n", test, buf, n); + r = -1; + } + + buf[sizeof(buf) - 1] = '\0'; + n = lws_b64_decode_string(coded[test], buf, sizeof buf); + if (n != strlen(plaintext[test]) || + strcmp(buf, plaintext[test])) { + lwsl_err("Failed lws_b64 decode selftest " + "%d result '%s' / '%s', %d / %d\n", + test, buf, plaintext[test], n, strlen(plaintext[test])); + r = -1; + } + } + + lwsl_notice("Base 64 selftests passed\n"); + + return r; +} +#endif |