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-rw-r--r--libmailutils/base64.c273
1 files changed, 273 insertions, 0 deletions
diff --git a/libmailutils/base64.c b/libmailutils/base64.c
new file mode 100644
index 000000000..7a8c62282
--- /dev/null
+++ b/libmailutils/base64.c
@@ -0,0 +1,273 @@
+/* GNU Mailutils -- a suite of utilities for electronic mail
+ Copyright (C) 2002, 2009, 2010 Free Software Foundation, Inc.
+
+ This library is free software; you can redistribute it and/or
+ modify it under the terms of the GNU Lesser General Public
+ License as published by the Free Software Foundation; either
+ version 3 of the License, or (at your option) any later version.
+
+ This library 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
+ Lesser General Public License for more details.
+
+ You should have received a copy of the GNU Lesser General Public License
+ along with GNU Mailutils. If not, see <http://www.gnu.org/licenses/>. */
+
+#ifdef HAVE_CONFIG_H
+# include <config.h>
+#endif
+
+#include <stdlib.h>
+#include <string.h>
+#include <mailutils/errno.h>
+#include <mailutils/filter.h>
+
+static char b64tab[] =
+ "ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz0123456789+/";
+static int b64val[128] = {
+ -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1,
+ -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1,
+ -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, 62, -1, -1, -1, 63,
+ 52, 53, 54, 55, 56, 57, 58, 59, 60, 61, -1, -1, -1, -1, -1, -1,
+ -1, 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, -1, -1, -1, -1, -1,
+ -1, 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, -1, -1, -1, -1, -1
+};
+
+int
+mu_base64_encode (const unsigned char *input, size_t input_len,
+ unsigned char **output, size_t *output_len)
+{
+ size_t olen = 4 * (input_len + 2) / 3 + 1;
+ unsigned char *out = malloc (olen);
+
+ if (!out)
+ return ENOMEM;
+ *output = out;
+ while (input_len >= 3)
+ {
+ *out++ = b64tab[input[0] >> 2];
+ *out++ = b64tab[((input[0] << 4) & 0x30) | (input[1] >> 4)];
+ *out++ = b64tab[((input[1] << 2) & 0x3c) | (input[2] >> 6)];
+ *out++ = b64tab[input[2] & 0x3f];
+ input_len -= 3;
+ input += 3;
+ }
+
+ if (input_len > 0)
+ {
+ unsigned char c = (input[0] << 4) & 0x30;
+ *out++ = b64tab[input[0] >> 2];
+ if (input_len > 1)
+ c |= input[1] >> 4;
+ *out++ = b64tab[c];
+ *out++ = (input_len < 2) ? '=' : b64tab[(input[1] << 2) & 0x3c];
+ *out++ = '=';
+ }
+ *output_len = out - *output;
+ *out = 0;
+ return 0;
+}
+
+int
+mu_base64_decode (const unsigned char *input, size_t input_len,
+ unsigned char **output, size_t *output_len)
+{
+ int olen = input_len;
+ unsigned char *out = malloc (olen);
+
+ if (!out)
+ return ENOMEM;
+ *output = out;
+ do
+ {
+ if (input[0] > 127 || b64val[input[0]] == -1
+ || input[1] > 127 || b64val[input[1]] == -1
+ || input[2] > 127 || ((input[2] != '=') && (b64val[input[2]] == -1))
+ || input[3] > 127 || ((input[3] != '=')
+ && (b64val[input[3]] == -1)))
+ return EINVAL;
+ *out++ = (b64val[input[0]] << 2) | (b64val[input[1]] >> 4);
+ if (input[2] != '=')
+ {
+ *out++ = ((b64val[input[1]] << 4) & 0xf0) | (b64val[input[2]] >> 2);
+ if (input[3] != '=')
+ *out++ = ((b64val[input[2]] << 6) & 0xc0) | b64val[input[3]];
+ }
+ input += 4;
+ input_len -= 4;
+ }
+ while (input_len > 0);
+ *output_len = out - *output;
+ return 0;
+}
+
+
+static enum mu_filter_result
+_base64_decoder (void *xd MU_ARG_UNUSED,
+ enum mu_filter_command cmd,
+ struct mu_filter_io *iobuf)
+{
+ int i = 0, tmp = 0, pad = 0;
+ size_t consumed = 0;
+ unsigned char data[4];
+ size_t nbytes = 0;
+ const char *iptr;
+ size_t isize;
+ char *optr;
+ size_t osize;
+
+ switch (cmd)
+ {
+ case mu_filter_init:
+ case mu_filter_done:
+ return mu_filter_ok;
+ default:
+ break;
+ }
+
+ if (osize <= 3)
+ {
+ iobuf->osize = 3;
+ return mu_filter_moreoutput;
+ }
+
+ iptr = iobuf->input;
+ isize = iobuf->isize;
+ optr = iobuf->output;
+ osize = iobuf->osize;
+
+ while (consumed < isize && nbytes + 3 < osize)
+ {
+ while (i < 4 && consumed < isize)
+ {
+ tmp = b64val[*(const unsigned char*)iptr++];
+ consumed++;
+ if (tmp != -1)
+ data[i++] = tmp;
+ else if (*(iptr-1) == '=')
+ {
+ data[i++] = 0;
+ pad++;
+ }
+ }
+
+ /* I have a entire block of data 32 bits get the output data. */
+ if (i == 4)
+ {
+ *optr++ = (data[0] << 2) | ((data[1] & 0x30) >> 4);
+ *optr++ = ((data[1] & 0xf) << 4) | ((data[2] & 0x3c) >> 2);
+ *optr++ = ((data[2] & 0x3) << 6) | data[3];
+ nbytes += 3 - pad;
+ }
+ else
+ {
+ /* I did not get all the data. */
+ consumed -= i;
+ break;
+ }
+ i = 0;
+ }
+ iobuf->isize = consumed;
+ iobuf->osize = nbytes;
+ return mu_filter_ok;
+}
+
+static enum mu_filter_result
+_base64_encoder (void *xd MU_ARG_UNUSED,
+ enum mu_filter_command cmd,
+ struct mu_filter_io *iobuf)
+{
+ size_t consumed = 0;
+ int pad = 0;
+ const unsigned char *ptr = (const unsigned char*) iobuf->input;
+ size_t nbytes = 0;
+ size_t isize;
+ char *optr;
+ size_t osize;
+
+ switch (cmd)
+ {
+ case mu_filter_init:
+ case mu_filter_done:
+ return mu_filter_ok;
+ default:
+ break;
+ }
+
+ if (iobuf->isize <= 3)
+ {
+ if (cmd == mu_filter_lastbuf)
+ pad = 1;
+ else
+ {
+ iobuf->isize = 4;
+ return mu_filter_moreinput;
+ }
+ }
+ if (osize < 4)
+ {
+ iobuf->osize = 4;
+ return mu_filter_moreoutput;
+ }
+
+ isize = iobuf->isize;
+ optr = iobuf->output;
+ osize = iobuf->osize;
+
+ while ((consumed + 3 <= isize && nbytes + 4 <= osize) || pad)
+ {
+ unsigned char c1 = 0, c2 = 0, x = '=', y = '=';
+
+ *optr++ = b64tab[ptr[0] >> 2];
+ consumed++;
+ switch (isize - consumed)
+ {
+ default:
+ consumed++;
+ y = b64tab[ptr[2] & 0x3f];
+ c2 = ptr[2] >> 6;
+ case 1:
+ consumed++;
+ x = b64tab[((ptr[1] << 2) + c2) & 0x3f];
+ c1 = (ptr[1] >> 4);
+ case 0:
+ *optr++ = b64tab[((ptr[0] << 4) + c1) & 0x3f];
+ *optr++ = x;
+ *optr++ = y;
+ }
+
+ ptr += 3;
+ nbytes += 4;
+ pad = 0;
+ }
+
+ /* Consumed may grow bigger than isize if cmd is mu_filter_lastbuf */
+ if (consumed > iobuf->isize)
+ consumed = iobuf->isize;
+ iobuf->isize = consumed;
+ iobuf->osize = nbytes;
+ return mu_filter_ok;
+}
+
+static struct _mu_filter_record _base64_filter = {
+ "base64",
+ 76,
+ NULL,
+ _base64_encoder,
+ _base64_decoder
+};
+
+mu_filter_record_t mu_base64_filter = &_base64_filter;
+
+static struct _mu_filter_record _B_filter = {
+ "B",
+ 0,
+ NULL,
+ _base64_encoder,
+ _base64_decoder
+};
+
+mu_filter_record_t mu_rfc_2047_B_filter = &_B_filter;

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