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Diffstat (limited to 'gl/lib/base64.c')
-rw-r--r-- | gl/lib/base64.c | 575 |
1 files changed, 0 insertions, 575 deletions
diff --git a/gl/lib/base64.c b/gl/lib/base64.c deleted file mode 100644 index a33f10216..000000000 --- a/gl/lib/base64.c +++ /dev/null @@ -1,575 +0,0 @@ -/* base64.c -- Encode binary data using printable characters. - Copyright (C) 1999, 2000, 2001, 2004, 2005, 2006, 2007 Free Software - Foundation, Inc. - - This program is free software: you can redistribute it and/or modify - it under the terms of the GNU General Public License as published by - the Free Software Foundation, either version 3 of the License, or - (at your option) any later version. - - This program is distributed in the hope that it will be useful, - but WITHOUT ANY WARRANTY; without even the implied warranty of - MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the - GNU General Public License for more details. - - You should have received a copy of the GNU General Public License - along with this program. If not, see <http://www.gnu.org/licenses/>. */ - -/* Written by Simon Josefsson. Partially adapted from GNU MailUtils - * (mailbox/filter_trans.c, as of 2004-11-28). Improved by review - * from Paul Eggert, Bruno Haible, and Stepan Kasal. - * - * See also RFC 3548 <http://www.ietf.org/rfc/rfc3548.txt>. - * - * Be careful with error checking. Here is how you would typically - * use these functions: - * - * bool ok = base64_decode_alloc (in, inlen, &out, &outlen); - * if (!ok) - * FAIL: input was not valid base64 - * if (out == NULL) - * FAIL: memory allocation error - * OK: data in OUT/OUTLEN - * - * size_t outlen = base64_encode_alloc (in, inlen, &out); - * if (out == NULL && outlen == 0 && inlen != 0) - * FAIL: input too long - * if (out == NULL) - * FAIL: memory allocation error - * OK: data in OUT/OUTLEN. - * - */ - -#include <config.h> - -/* Get prototype. */ -#include "base64.h" - -/* Get malloc. */ -#include <stdlib.h> - -/* Get UCHAR_MAX. */ -#include <limits.h> - -#include <string.h> - -/* C89 compliant way to cast 'char' to 'unsigned char'. */ -static inline unsigned char -to_uchar (char ch) -{ - return ch; -} - -/* Base64 encode IN array of size INLEN into OUT array of size OUTLEN. - If OUTLEN is less than BASE64_LENGTH(INLEN), write as many bytes as - possible. If OUTLEN is larger than BASE64_LENGTH(INLEN), also zero - terminate the output buffer. */ -void -base64_encode (const char *restrict in, size_t inlen, - char *restrict out, size_t outlen) -{ - static const char b64str[64] = - "ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz0123456789+/"; - - while (inlen && outlen) - { - *out++ = b64str[(to_uchar (in[0]) >> 2) & 0x3f]; - if (!--outlen) - break; - *out++ = b64str[((to_uchar (in[0]) << 4) - + (--inlen ? to_uchar (in[1]) >> 4 : 0)) - & 0x3f]; - if (!--outlen) - break; - *out++ = - (inlen - ? b64str[((to_uchar (in[1]) << 2) - + (--inlen ? to_uchar (in[2]) >> 6 : 0)) - & 0x3f] - : '='); - if (!--outlen) - break; - *out++ = inlen ? b64str[to_uchar (in[2]) & 0x3f] : '='; - if (!--outlen) - break; - if (inlen) - inlen--; - if (inlen) - in += 3; - } - - if (outlen) - *out = '\0'; -} - -/* Allocate a buffer and store zero terminated base64 encoded data - from array IN of size INLEN, returning BASE64_LENGTH(INLEN), i.e., - the length of the encoded data, excluding the terminating zero. On - return, the OUT variable will hold a pointer to newly allocated - memory that must be deallocated by the caller. If output string - length would overflow, 0 is returned and OUT is set to NULL. If - memory allocation failed, OUT is set to NULL, and the return value - indicates length of the requested memory block, i.e., - BASE64_LENGTH(inlen) + 1. */ -size_t -base64_encode_alloc (const char *in, size_t inlen, char **out) -{ - size_t outlen = 1 + BASE64_LENGTH (inlen); - - /* Check for overflow in outlen computation. - * - * If there is no overflow, outlen >= inlen. - * - * If the operation (inlen + 2) overflows then it yields at most +1, so - * outlen is 0. - * - * If the multiplication overflows, we lose at least half of the - * correct value, so the result is < ((inlen + 2) / 3) * 2, which is - * less than (inlen + 2) * 0.66667, which is less than inlen as soon as - * (inlen > 4). - */ - if (inlen > outlen) - { - *out = NULL; - return 0; - } - - *out = malloc (outlen); - if (!*out) - return outlen; - - base64_encode (in, inlen, *out, outlen); - - return outlen - 1; -} - -/* With this approach this file works independent of the charset used - (think EBCDIC). However, it does assume that the characters in the - Base64 alphabet (A-Za-z0-9+/) are encoded in 0..255. POSIX - 1003.1-2001 require that char and unsigned char are 8-bit - quantities, though, taking care of that problem. But this may be a - potential problem on non-POSIX C99 platforms. - - IBM C V6 for AIX mishandles "#define B64(x) ...'x'...", so use "_" - as the formal parameter rather than "x". */ -#define B64(_) \ - ((_) == 'A' ? 0 \ - : (_) == 'B' ? 1 \ - : (_) == 'C' ? 2 \ - : (_) == 'D' ? 3 \ - : (_) == 'E' ? 4 \ - : (_) == 'F' ? 5 \ - : (_) == 'G' ? 6 \ - : (_) == 'H' ? 7 \ - : (_) == 'I' ? 8 \ - : (_) == 'J' ? 9 \ - : (_) == 'K' ? 10 \ - : (_) == 'L' ? 11 \ - : (_) == 'M' ? 12 \ - : (_) == 'N' ? 13 \ - : (_) == 'O' ? 14 \ - : (_) == 'P' ? 15 \ - : (_) == 'Q' ? 16 \ - : (_) == 'R' ? 17 \ - : (_) == 'S' ? 18 \ - : (_) == 'T' ? 19 \ - : (_) == 'U' ? 20 \ - : (_) == 'V' ? 21 \ - : (_) == 'W' ? 22 \ - : (_) == 'X' ? 23 \ - : (_) == 'Y' ? 24 \ - : (_) == 'Z' ? 25 \ - : (_) == 'a' ? 26 \ - : (_) == 'b' ? 27 \ - : (_) == 'c' ? 28 \ - : (_) == 'd' ? 29 \ - : (_) == 'e' ? 30 \ - : (_) == 'f' ? 31 \ - : (_) == 'g' ? 32 \ - : (_) == 'h' ? 33 \ - : (_) == 'i' ? 34 \ - : (_) == 'j' ? 35 \ - : (_) == 'k' ? 36 \ - : (_) == 'l' ? 37 \ - : (_) == 'm' ? 38 \ - : (_) == 'n' ? 39 \ - : (_) == 'o' ? 40 \ - : (_) == 'p' ? 41 \ - : (_) == 'q' ? 42 \ - : (_) == 'r' ? 43 \ - : (_) == 's' ? 44 \ - : (_) == 't' ? 45 \ - : (_) == 'u' ? 46 \ - : (_) == 'v' ? 47 \ - : (_) == 'w' ? 48 \ - : (_) == 'x' ? 49 \ - : (_) == 'y' ? 50 \ - : (_) == 'z' ? 51 \ - : (_) == '0' ? 52 \ - : (_) == '1' ? 53 \ - : (_) == '2' ? 54 \ - : (_) == '3' ? 55 \ - : (_) == '4' ? 56 \ - : (_) == '5' ? 57 \ - : (_) == '6' ? 58 \ - : (_) == '7' ? 59 \ - : (_) == '8' ? 60 \ - : (_) == '9' ? 61 \ - : (_) == '+' ? 62 \ - : (_) == '/' ? 63 \ - : -1) - -static const signed char b64[0x100] = { - B64 (0), B64 (1), B64 (2), B64 (3), - B64 (4), B64 (5), B64 (6), B64 (7), - B64 (8), B64 (9), B64 (10), B64 (11), - B64 (12), B64 (13), B64 (14), B64 (15), - B64 (16), B64 (17), B64 (18), B64 (19), - B64 (20), B64 (21), B64 (22), B64 (23), - B64 (24), B64 (25), B64 (26), B64 (27), - B64 (28), B64 (29), B64 (30), B64 (31), - B64 (32), B64 (33), B64 (34), B64 (35), - B64 (36), B64 (37), B64 (38), B64 (39), - B64 (40), B64 (41), B64 (42), B64 (43), - B64 (44), B64 (45), B64 (46), B64 (47), - B64 (48), B64 (49), B64 (50), B64 (51), - B64 (52), B64 (53), B64 (54), B64 (55), - B64 (56), B64 (57), B64 (58), B64 (59), - B64 (60), B64 (61), B64 (62), B64 (63), - B64 (64), B64 (65), B64 (66), B64 (67), - B64 (68), B64 (69), B64 (70), B64 (71), - B64 (72), B64 (73), B64 (74), B64 (75), - B64 (76), B64 (77), B64 (78), B64 (79), - B64 (80), B64 (81), B64 (82), B64 (83), - B64 (84), B64 (85), B64 (86), B64 (87), - B64 (88), B64 (89), B64 (90), B64 (91), - B64 (92), B64 (93), B64 (94), B64 (95), - B64 (96), B64 (97), B64 (98), B64 (99), - B64 (100), B64 (101), B64 (102), B64 (103), - B64 (104), B64 (105), B64 (106), B64 (107), - B64 (108), B64 (109), B64 (110), B64 (111), - B64 (112), B64 (113), B64 (114), B64 (115), - B64 (116), B64 (117), B64 (118), B64 (119), - B64 (120), B64 (121), B64 (122), B64 (123), - B64 (124), B64 (125), B64 (126), B64 (127), - B64 (128), B64 (129), B64 (130), B64 (131), - B64 (132), B64 (133), B64 (134), B64 (135), - B64 (136), B64 (137), B64 (138), B64 (139), - B64 (140), B64 (141), B64 (142), B64 (143), - B64 (144), B64 (145), B64 (146), B64 (147), - B64 (148), B64 (149), B64 (150), B64 (151), - B64 (152), B64 (153), B64 (154), B64 (155), - B64 (156), B64 (157), B64 (158), B64 (159), - B64 (160), B64 (161), B64 (162), B64 (163), - B64 (164), B64 (165), B64 (166), B64 (167), - B64 (168), B64 (169), B64 (170), B64 (171), - B64 (172), B64 (173), B64 (174), B64 (175), - B64 (176), B64 (177), B64 (178), B64 (179), - B64 (180), B64 (181), B64 (182), B64 (183), - B64 (184), B64 (185), B64 (186), B64 (187), - B64 (188), B64 (189), B64 (190), B64 (191), - B64 (192), B64 (193), B64 (194), B64 (195), - B64 (196), B64 (197), B64 (198), B64 (199), - B64 (200), B64 (201), B64 (202), B64 (203), - B64 (204), B64 (205), B64 (206), B64 (207), - B64 (208), B64 (209), B64 (210), B64 (211), - B64 (212), B64 (213), B64 (214), B64 (215), - B64 (216), B64 (217), B64 (218), B64 (219), - B64 (220), B64 (221), B64 (222), B64 (223), - B64 (224), B64 (225), B64 (226), B64 (227), - B64 (228), B64 (229), B64 (230), B64 (231), - B64 (232), B64 (233), B64 (234), B64 (235), - B64 (236), B64 (237), B64 (238), B64 (239), - B64 (240), B64 (241), B64 (242), B64 (243), - B64 (244), B64 (245), B64 (246), B64 (247), - B64 (248), B64 (249), B64 (250), B64 (251), - B64 (252), B64 (253), B64 (254), B64 (255) -}; - -#if UCHAR_MAX == 255 -# define uchar_in_range(c) true -#else -# define uchar_in_range(c) ((c) <= 255) -#endif - -/* Return true if CH is a character from the Base64 alphabet, and - false otherwise. Note that '=' is padding and not considered to be - part of the alphabet. */ -bool -isbase64 (char ch) -{ - return uchar_in_range (to_uchar (ch)) && 0 <= b64[to_uchar (ch)]; -} - -/* Initialize decode-context buffer, CTX. */ -void -base64_decode_ctx_init (struct base64_decode_context *ctx) -{ - ctx->i = 0; -} - -/* If CTX->i is 0 or 4, there are four or more bytes in [*IN..IN_END), and - none of those four is a newline, then return *IN. Otherwise, copy up to - 4 - CTX->i non-newline bytes from that range into CTX->buf, starting at - index CTX->i and setting CTX->i to reflect the number of bytes copied, - and return CTX->buf. In either case, advance *IN to point to the byte - after the last one processed, and set *N_NON_NEWLINE to the number of - verified non-newline bytes accessible through the returned pointer. */ -static inline char * -get_4 (struct base64_decode_context *ctx, - char const *restrict *in, char const *restrict in_end, - size_t *n_non_newline) -{ - if (ctx->i == 4) - ctx->i = 0; - - if (ctx->i == 0) - { - char const *t = *in; - if (4 <= in_end - *in && memchr (t, '\n', 4) == NULL) - { - /* This is the common case: no newline. */ - *in += 4; - *n_non_newline = 4; - return (char *) t; - } - } - - { - /* Copy non-newline bytes into BUF. */ - char const *p = *in; - while (p < in_end) - { - char c = *p++; - if (c != '\n') - { - ctx->buf[ctx->i++] = c; - if (ctx->i == 4) - break; - } - } - - *in = p; - *n_non_newline = ctx->i; - return ctx->buf; - } -} - -#define return_false \ - do \ - { \ - *outp = out; \ - return false; \ - } \ - while (false) - -/* Decode up to four bytes of base64-encoded data, IN, of length INLEN - into the output buffer, *OUT, of size *OUTLEN bytes. Return true if - decoding is successful, false otherwise. If *OUTLEN is too small, - as many bytes as possible are written to *OUT. On return, advance - *OUT to point to the byte after the last one written, and decrement - *OUTLEN to reflect the number of bytes remaining in *OUT. */ -static inline bool -decode_4 (char const *restrict in, size_t inlen, - char *restrict *outp, size_t *outleft) -{ - char *out = *outp; - if (inlen < 2) - return false; - - if (!isbase64 (in[0]) || !isbase64 (in[1])) - return false; - - if (*outleft) - { - *out++ = ((b64[to_uchar (in[0])] << 2) - | (b64[to_uchar (in[1])] >> 4)); - --*outleft; - } - - if (inlen == 2) - return_false; - - if (in[2] == '=') - { - if (inlen != 4) - return_false; - - if (in[3] != '=') - return_false; - } - else - { - if (!isbase64 (in[2])) - return_false; - - if (*outleft) - { - *out++ = (((b64[to_uchar (in[1])] << 4) & 0xf0) - | (b64[to_uchar (in[2])] >> 2)); - --*outleft; - } - - if (inlen == 3) - return_false; - - if (in[3] == '=') - { - if (inlen != 4) - return_false; - } - else - { - if (!isbase64 (in[3])) - return_false; - - if (*outleft) - { - *out++ = (((b64[to_uchar (in[2])] << 6) & 0xc0) - | b64[to_uchar (in[3])]); - --*outleft; - } - } - } - - *outp = out; - return true; -} - -/* Decode base64-encoded input array IN of length INLEN to output array - OUT that can hold *OUTLEN bytes. The input data may be interspersed - with newlines. Return true if decoding was successful, i.e. if the - input was valid base64 data, false otherwise. If *OUTLEN is too - small, as many bytes as possible will be written to OUT. On return, - *OUTLEN holds the length of decoded bytes in OUT. Note that as soon - as any non-alphabet, non-newline character is encountered, decoding - is stopped and false is returned. If INLEN is zero, then process - only whatever data is stored in CTX. - - Initially, CTX must have been initialized via base64_decode_ctx_init. - Subsequent calls to this function must reuse whatever state is recorded - in that buffer. It is necessary for when a quadruple of base64 input - bytes spans two input buffers. - - If CTX is NULL then newlines are treated as garbage and the input - buffer is processed as a unit. */ - -bool -base64_decode_ctx (struct base64_decode_context *ctx, - const char *restrict in, size_t inlen, - char *restrict out, size_t *outlen) -{ - size_t outleft = *outlen; - bool ignore_newlines = ctx != NULL; - bool flush_ctx = false; - unsigned int ctx_i = 0; - - if (ignore_newlines) - { - ctx_i = ctx->i; - flush_ctx = inlen == 0; - } - - - while (true) - { - size_t outleft_save = outleft; - if (ctx_i == 0 && !flush_ctx) - { - while (true) - { - /* Save a copy of outleft, in case we need to re-parse this - block of four bytes. */ - outleft_save = outleft; - if (!decode_4 (in, inlen, &out, &outleft)) - break; - - in += 4; - inlen -= 4; - } - } - - if (inlen == 0 && !flush_ctx) - break; - - /* Handle the common case of 72-byte wrapped lines. - This also handles any other multiple-of-4-byte wrapping. */ - if (inlen && *in == '\n' && ignore_newlines) - { - ++in; - --inlen; - continue; - } - - /* Restore OUT and OUTLEFT. */ - out -= outleft_save - outleft; - outleft = outleft_save; - - { - char const *in_end = in + inlen; - char const *non_nl; - - if (ignore_newlines) - non_nl = get_4 (ctx, &in, in_end, &inlen); - else - non_nl = in; /* Might have nl in this case. */ - - /* If the input is empty or consists solely of newlines (0 non-newlines), - then we're done. Likewise if there are fewer than 4 bytes when not - flushing context and not treating newlines as garbage. */ - if (inlen == 0 || (inlen < 4 && !flush_ctx && ignore_newlines)) - { - inlen = 0; - break; - } - if (!decode_4 (non_nl, inlen, &out, &outleft)) - break; - - inlen = in_end - in; - } - } - - *outlen -= outleft; - - return inlen == 0; -} - -/* Allocate an output buffer in *OUT, and decode the base64 encoded - data stored in IN of size INLEN to the *OUT buffer. On return, the - size of the decoded data is stored in *OUTLEN. OUTLEN may be NULL, - if the caller is not interested in the decoded length. *OUT may be - NULL to indicate an out of memory error, in which case *OUTLEN - contains the size of the memory block needed. The function returns - true on successful decoding and memory allocation errors. (Use the - *OUT and *OUTLEN parameters to differentiate between successful - decoding and memory error.) The function returns false if the - input was invalid, in which case *OUT is NULL and *OUTLEN is - undefined. */ -bool -base64_decode_alloc_ctx (struct base64_decode_context *ctx, - const char *in, size_t inlen, char **out, - size_t *outlen) -{ - /* This may allocate a few bytes too many, depending on input, - but it's not worth the extra CPU time to compute the exact size. - The exact size is 3 * inlen / 4, minus 1 if the input ends - with "=" and minus another 1 if the input ends with "==". - Dividing before multiplying avoids the possibility of overflow. */ - size_t needlen = 3 * (inlen / 4) + 2; - - *out = malloc (needlen); - if (!*out) - return true; - - if (!base64_decode_ctx (ctx, in, inlen, *out, &needlen)) - { - free (*out); - *out = NULL; - return false; - } - - if (outlen) - *outlen = needlen; - - return true; -} |