Adding upstream version 8.32.upstream/8.32upstream

Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>

1 files changed, 605 insertions, 0 deletions

diff --git a/lib/base64.c b/lib/base64.c
new file mode 100644
index 0000000..c7ef82c
--- /dev/null
+++ b/lib/base64.c
@@ -0,0 +1,605 @@
+/* base64.c -- Encode binary data using printable characters.
+   Copyright (C) 1999-2001, 2004-2006, 2009-2020 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, 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 <https://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 4648 <https://www.ietf.org/rfc/rfc4648.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 unsigned char
+to_uchar (char ch)
+{
+  return ch;
+}
+
+static const char b64c[64] =
+  "ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz0123456789+/";
+
+/* Base64 encode IN array of size INLEN into OUT array. OUT needs
+   to be of length >= BASE64_LENGTH(INLEN), and INLEN needs to be
+   a multiple of 3.  */
+static void
+base64_encode_fast (const char *restrict in, size_t inlen, char *restrict out)
+{
+  while (inlen)
+    {
+      *out++ = b64c[(to_uchar (in[0]) >> 2) & 0x3f];
+      *out++ = b64c[((to_uchar (in[0]) << 4) + (to_uchar (in[1]) >> 4)) & 0x3f];
+      *out++ = b64c[((to_uchar (in[1]) << 2) + (to_uchar (in[2]) >> 6)) & 0x3f];
+      *out++ = b64c[to_uchar (in[2]) & 0x3f];
+
+      inlen -= 3;
+      in += 3;
+    }
+}
+
+/* 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)
+{
+  /* Note this outlen constraint can be enforced at compile time.
+     I.E. that the output buffer is exactly large enough to hold
+     the encoded inlen bytes.  The inlen constraints (of corresponding
+     to outlen, and being a multiple of 3) can change at runtime
+     at the end of input.  However the common case when reading
+     large inputs is to have both constraints satisfied, so we depend
+     on both in base_encode_fast().  */
+  if (outlen % 4 == 0 && inlen == outlen / 4 * 3)
+    {
+      base64_encode_fast (in, inlen, out);
+      return;
+    }
+
+  while (inlen && outlen)
+    {
+      *out++ = b64c[(to_uchar (in[0]) >> 2) & 0x3f];
+      if (!--outlen)
+        break;
+      *out++ = b64c[((to_uchar (in[0]) << 4)
+                       + (--inlen ? to_uchar (in[1]) >> 4 : 0))
+                      & 0x3f];
+      if (!--outlen)
+        break;
+      *out++ =
+        (inlen
+         ? b64c[((to_uchar (in[1]) << 2)
+                   + (--inlen ? to_uchar (in[2]) >> 6 : 0))
+                  & 0x3f]
+         : '=');
+      if (!--outlen)
+        break;
+      *out++ = inlen ? b64c[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 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 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 + (ctx ? ctx->i : 0)) / 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) + 3;
+
+  *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;
+}