--- /dev/null
+/* Licensed under BSD-MIT - see LICENSE file for details */
+#include "base64.h"
+
+#include <errno.h>
+#include <string.h>
+#include <assert.h>
+#include <stdint.h>
+
+/**
+ * sixbit_to_b64 - maps a 6-bit value to the base64 alphabet
+ * @param map A base 64 map (see base64_init_map)
+ * @param sixbit Six-bit value to map
+ * @return a base 64 character
+ */
+static char sixbit_to_b64(const base64_maps_t *maps, const uint8_t sixbit)
+{
+ assert(sixbit >= 0);
+ assert(sixbit <= 63);
+
+ return maps->encode_map[(unsigned char)sixbit];
+}
+
+/**
+ * sixbit_from_b64 - maps a base64-alphabet character to its 6-bit value
+ * @param maps A base 64 maps structure (see base64_init_maps)
+ * @param sixbit Six-bit value to map
+ * @return a six-bit value
+ */
+static int8_t sixbit_from_b64(const base64_maps_t *maps,
+ const unsigned char b64letter)
+{
+ int8_t ret;
+
+ ret = maps->decode_map[(unsigned char)b64letter];
+ if (ret == (char)0xff) {
+ errno = EDOM;
+ return -1;
+ }
+
+ return ret;
+}
+
+bool base64_char_in_alphabet(const base64_maps_t *maps, const char b64char)
+{
+ return (maps->decode_map[(const unsigned char)b64char] != (char)0xff);
+}
+
+void base64_init_maps(base64_maps_t *dest, const char src[64])
+{
+ unsigned char i;
+
+ memcpy(dest->encode_map,src,64);
+ memset(dest->decode_map,0xff,256);
+ for (i=0; i<64; i++) {
+ dest->decode_map[(unsigned char)src[i]] = i;
+ }
+}
+
+size_t base64_encoded_length(size_t srclen)
+{
+ return ((srclen + 2) / 3) * 4;
+}
+
+void base64_encode_triplet_using_maps(const base64_maps_t *maps,
+ char dest[4], const char src[3])
+{
+ char a = src[0];
+ char b = src[1];
+ char c = src[2];
+
+ dest[0] = sixbit_to_b64(maps, (a & 0xfc) >> 2);
+ dest[1] = sixbit_to_b64(maps, ((a & 0x3) << 4) | ((b & 0xf0) >> 4));
+ dest[2] = sixbit_to_b64(maps, ((c & 0xc0) >> 6) | ((b & 0xf) << 2));
+ dest[3] = sixbit_to_b64(maps, c & 0x3f);
+}
+
+void base64_encode_tail_using_maps(const base64_maps_t *maps, char dest[4],
+ const char *src, const size_t srclen)
+{
+ char longsrc[3] = { 0 };
+
+ assert(srclen <= 3);
+
+ memcpy(longsrc, src, srclen);
+ base64_encode_triplet_using_maps(maps, dest, longsrc);
+ memset(dest+1+srclen, '=', 3-srclen);
+}
+
+ssize_t base64_encode_using_maps(const base64_maps_t *maps,
+ char *dest, const size_t destlen,
+ const char *src, const size_t srclen)
+{
+ size_t src_offset = 0;
+ size_t dest_offset = 0;
+
+ if (destlen < base64_encoded_length(srclen)) {
+ errno = EOVERFLOW;
+ return -1;
+ }
+
+ while (srclen - src_offset >= 3) {
+ base64_encode_triplet_using_maps(maps, &dest[dest_offset], &src[src_offset]);
+ src_offset += 3;
+ dest_offset += 4;
+ }
+
+ if (src_offset < srclen) {
+ base64_encode_tail_using_maps(maps, &dest[dest_offset], &src[src_offset], srclen-src_offset);
+ dest_offset += 4;
+ }
+
+ memset(&dest[dest_offset], '\0', destlen-dest_offset);
+
+ return dest_offset;
+}
+
+size_t base64_decoded_length(size_t srclen)
+{
+ return ((srclen+3)/4*3);
+}
+
+int base64_decode_quartet_using_maps(const base64_maps_t *maps, char dest[3],
+ const char src[4])
+{
+ signed char a;
+ signed char b;
+ signed char c;
+ signed char d;
+
+ a = sixbit_from_b64(maps, src[0]);
+ b = sixbit_from_b64(maps, src[1]);
+ c = sixbit_from_b64(maps, src[2]);
+ d = sixbit_from_b64(maps, src[3]);
+
+ if ((a == -1) || (b == -1) || (c == -1) || (d == -1)) {
+ return -1;
+ }
+
+ dest[0] = (a << 2) | (b >> 4);
+ dest[1] = ((b & 0xf) << 4) | (c >> 2);
+ dest[2] = ((c & 0x3) << 6) | d;
+
+ return 0;
+}
+
+
+int base64_decode_tail_using_maps(const base64_maps_t *maps, char dest[3],
+ const char * src, const size_t srclen)
+{
+ char longsrc[4];
+ int quartet_result;
+ size_t insize = srclen;
+
+ while (insize != 0 &&
+ src[insize-1] == '=') { /* throw away padding symbols */
+ insize--;
+ }
+ if (insize == 0) {
+ return 0;
+ }
+ if (insize == 1) {
+ /* the input is malformed.... */
+ errno = EINVAL;
+ return -1;
+ }
+ memcpy(longsrc, src, insize);
+ memset(longsrc+insize, 'A', 4-insize);
+ quartet_result = base64_decode_quartet_using_maps(maps, dest, longsrc);
+ if (quartet_result == -1) {
+ return -1;
+ }
+
+ return insize - 1;
+}
+
+ssize_t base64_decode_using_maps(const base64_maps_t *maps,
+ char *dest, const size_t destlen,
+ const char *src, const size_t srclen)
+{
+ ssize_t dest_offset = 0;
+ ssize_t i;
+ size_t more;
+
+ if (destlen < base64_decoded_length(srclen)) {
+ errno = EOVERFLOW;
+ return -1;
+ }
+
+ for(i=0; srclen - i > 4; i+=4) {
+ if (base64_decode_quartet_using_maps(maps, &dest[dest_offset], &src[i]) == -1) {
+ return -1;
+ }
+ dest_offset += 3;
+ }
+
+ more = base64_decode_tail_using_maps(maps, &dest[dest_offset], &src[i], srclen - i);
+ if (more == -1) {
+ return -1;
+ }
+ dest_offset += more;
+
+ memset(&dest[dest_offset], '\0', destlen-dest_offset);
+
+ return dest_offset;
+}
+
+
+
+
+/**
+ * base64_maps_rfc4648 - pregenerated maps struct for rfc4648
+ */
+static const base64_maps_t base64_maps_rfc4648 = {
+ "ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz0123456789+/",
+
+ "\xff\xff\xff\xff\xff" /* 0 */ \
+ "\xff\xff\xff\xff\xff" /* 5 */ \
+ "\xff\xff\xff\xff\xff" /* 10 */ \
+ "\xff\xff\xff\xff\xff" /* 15 */ \
+ "\xff\xff\xff\xff\xff" /* 20 */ \
+ "\xff\xff\xff\xff\xff" /* 25 */ \
+ "\xff\xff\xff\xff\xff" /* 30 */ \
+ "\xff\xff\xff\xff\xff" /* 35 */ \
+ "\xff\xff\xff\x3e\xff" /* 40 */ \
+ "\xff\xff\x3f\x34\x35" /* 45 */ \
+ "\x36\x37\x38\x39\x3a" /* 50 */ \
+ "\x3b\x3c\x3d\xff\xff" /* 55 */ \
+ "\xff\xff\xff\xff\xff" /* 60 */ \
+ "\x00\x01\x02\x03\x04" /* 65 A */ \
+ "\x05\x06\x07\x08\x09" /* 70 */ \
+ "\x0a\x0b\x0c\x0d\x0e" /* 75 */ \
+ "\x0f\x10\x11\x12\x13" /* 80 */ \
+ "\x14\x15\x16\x17\x18" /* 85 */ \
+ "\x19\xff\xff\xff\xff" /* 90 */ \
+ "\xff\xff\x1a\x1b\x1c" /* 95 */ \
+ "\x1d\x1e\x1f\x20\x21" /* 100 */ \
+ "\x22\x23\x24\x25\x26" /* 105 */ \
+ "\x27\x28\x29\x2a\x2b" /* 110 */ \
+ "\x2c\x2d\x2e\x2f\x30" /* 115 */ \
+ "\x31\x32\x33\xff\xff" /* 120 */ \
+ "\xff\xff\xff\xff\xff\xff\xff\xff\xff\xff" /* 125 */ \
+ "\xff\xff\xff\xff\xff\xff\xff\xff\xff\xff" \
+ "\xff\xff\xff\xff\xff\xff\xff\xff\xff\xff" \
+ "\xff\xff\xff\xff\xff\xff\xff\xff\xff\xff" /* 155 */ \
+ "\xff\xff\xff\xff\xff\xff\xff\xff\xff\xff" \
+ "\xff\xff\xff\xff\xff\xff\xff\xff\xff\xff" \
+ "\xff\xff\xff\xff\xff\xff\xff\xff\xff\xff" /* 185 */ \
+ "\xff\xff\xff\xff\xff\xff\xff\xff\xff\xff" \
+ "\xff\xff\xff\xff\xff\xff\xff\xff\xff\xff" \
+ "\xff\xff\xff\xff\xff\xff\xff\xff\xff\xff" /* 215 */ \
+ "\xff\xff\xff\xff\xff\xff\xff\xff\xff\xff" \
+ "\xff\xff\xff\xff\xff\xff\xff\xff\xff\xff" \
+ "\xff\xff\xff\xff\xff\xff\xff\xff\xff\xff\xff" /* 245 */
+};
projects / ccan / blobdiff