+int unbase32hexmem(const char *p, size_t l, bool padding, void **mem, size_t *_len) {
+ _cleanup_free_ uint8_t *r = NULL;
+ int a, b, c, d, e, f, g, h;
+ uint8_t *z;
+ const char *x;
+ size_t len;
+ unsigned pad = 0;
+
+ assert(p);
+
+ /* padding ensures any base32hex input has input divisible by 8 */
+ if (padding && l % 8 != 0)
+ return -EINVAL;
+
+ if (padding) {
+ /* strip the padding */
+ while (l > 0 && p[l - 1] == '=' && pad < 7) {
+ pad ++;
+ l --;
+ }
+ }
+
+ /* a group of eight input bytes needs five output bytes, in case of
+ padding we need to add some extra bytes */
+ len = (l / 8) * 5;
+
+ switch (l % 8) {
+ case 7:
+ len += 4;
+ break;
+ case 5:
+ len += 3;
+ break;
+ case 4:
+ len += 2;
+ break;
+ case 2:
+ len += 1;
+ break;
+ case 0:
+ break;
+ default:
+ return -EINVAL;
+ }
+
+ z = r = malloc(len + 1);
+ if (!r)
+ return -ENOMEM;
+
+ for (x = p; x < p + (l / 8) * 8; x += 8) {
+ /* a == 000XXXXX; b == 000YYYYY; c == 000ZZZZZ; d == 000WWWWW
+ e == 000SSSSS; f == 000QQQQQ; g == 000VVVVV; h == 000RRRRR */
+ a = unbase32hexchar(x[0]);
+ if (a < 0)
+ return -EINVAL;
+
+ b = unbase32hexchar(x[1]);
+ if (b < 0)
+ return -EINVAL;
+
+ c = unbase32hexchar(x[2]);
+ if (c < 0)
+ return -EINVAL;
+
+ d = unbase32hexchar(x[3]);
+ if (d < 0)
+ return -EINVAL;
+
+ e = unbase32hexchar(x[4]);
+ if (e < 0)
+ return -EINVAL;
+
+ f = unbase32hexchar(x[5]);
+ if (f < 0)
+ return -EINVAL;
+
+ g = unbase32hexchar(x[6]);
+ if (g < 0)
+ return -EINVAL;
+
+ h = unbase32hexchar(x[7]);
+ if (h < 0)
+ return -EINVAL;
+
+ *(z++) = (uint8_t) a << 3 | (uint8_t) b >> 2; /* XXXXXYYY */
+ *(z++) = (uint8_t) b << 6 | (uint8_t) c << 1 | (uint8_t) d >> 4; /* YYZZZZZW */
+ *(z++) = (uint8_t) d << 4 | (uint8_t) e >> 1; /* WWWWSSSS */
+ *(z++) = (uint8_t) e << 7 | (uint8_t) f << 2 | (uint8_t) g >> 3; /* SQQQQQVV */
+ *(z++) = (uint8_t) g << 5 | (uint8_t) h; /* VVVRRRRR */
+ }
+
+ switch (l % 8) {
+ case 7:
+ a = unbase32hexchar(x[0]);
+ if (a < 0)
+ return -EINVAL;
+
+ b = unbase32hexchar(x[1]);
+ if (b < 0)
+ return -EINVAL;
+
+ c = unbase32hexchar(x[2]);
+ if (c < 0)
+ return -EINVAL;
+
+ d = unbase32hexchar(x[3]);
+ if (d < 0)
+ return -EINVAL;
+
+ e = unbase32hexchar(x[4]);
+ if (e < 0)
+ return -EINVAL;
+
+ f = unbase32hexchar(x[5]);
+ if (f < 0)
+ return -EINVAL;
+
+ g = unbase32hexchar(x[6]);
+ if (g < 0)
+ return -EINVAL;
+
+ /* g == 000VV000 */
+ if (g & 7)
+ return -EINVAL;
+
+ *(z++) = (uint8_t) a << 3 | (uint8_t) b >> 2; /* XXXXXYYY */
+ *(z++) = (uint8_t) b << 6 | (uint8_t) c << 1 | (uint8_t) d >> 4; /* YYZZZZZW */
+ *(z++) = (uint8_t) d << 4 | (uint8_t) e >> 1; /* WWWWSSSS */
+ *(z++) = (uint8_t) e << 7 | (uint8_t) f << 2 | (uint8_t) g >> 3; /* SQQQQQVV */
+
+ break;
+ case 5:
+ a = unbase32hexchar(x[0]);
+ if (a < 0)
+ return -EINVAL;
+
+ b = unbase32hexchar(x[1]);
+ if (b < 0)
+ return -EINVAL;
+
+ c = unbase32hexchar(x[2]);
+ if (c < 0)
+ return -EINVAL;
+
+ d = unbase32hexchar(x[3]);
+ if (d < 0)
+ return -EINVAL;
+
+ e = unbase32hexchar(x[4]);
+ if (e < 0)
+ return -EINVAL;
+
+ /* e == 000SSSS0 */
+ if (e & 1)
+ return -EINVAL;
+
+ *(z++) = (uint8_t) a << 3 | (uint8_t) b >> 2; /* XXXXXYYY */
+ *(z++) = (uint8_t) b << 6 | (uint8_t) c << 1 | (uint8_t) d >> 4; /* YYZZZZZW */
+ *(z++) = (uint8_t) d << 4 | (uint8_t) e >> 1; /* WWWWSSSS */
+
+ break;
+ case 4:
+ a = unbase32hexchar(x[0]);
+ if (a < 0)
+ return -EINVAL;
+
+ b = unbase32hexchar(x[1]);
+ if (b < 0)
+ return -EINVAL;
+
+ c = unbase32hexchar(x[2]);
+ if (c < 0)
+ return -EINVAL;
+
+ d = unbase32hexchar(x[3]);
+ if (d < 0)
+ return -EINVAL;
+
+ /* d == 000W0000 */
+ if (d & 15)
+ return -EINVAL;
+
+ *(z++) = (uint8_t) a << 3 | (uint8_t) b >> 2; /* XXXXXYYY */
+ *(z++) = (uint8_t) b << 6 | (uint8_t) c << 1 | (uint8_t) d >> 4; /* YYZZZZZW */
+
+ break;
+ case 2:
+ a = unbase32hexchar(x[0]);
+ if (a < 0)
+ return -EINVAL;
+
+ b = unbase32hexchar(x[1]);
+ if (b < 0)
+ return -EINVAL;
+
+ /* b == 000YYY00 */
+ if (b & 3)
+ return -EINVAL;
+
+ *(z++) = (uint8_t) a << 3 | (uint8_t) b >> 2; /* XXXXXYYY */
+
+ break;
+ case 0:
+ break;
+ default:
+ return -EINVAL;
+ }
+
+ *z = 0;
+
+ *mem = r;
+ r = NULL;
+ *_len = len;
+
+ return 0;
+}
+
+/* https://tools.ietf.org/html/rfc4648#section-4 */
+char base64char(int x) {
+ static const char table[64] = "ABCDEFGHIJKLMNOPQRSTUVWXYZ"
+ "abcdefghijklmnopqrstuvwxyz"
+ "0123456789+/";
+ return table[x & 63];
+}
+
+int unbase64char(char c) {
+ unsigned offset;
+
+ if (c >= 'A' && c <= 'Z')
+ return c - 'A';
+
+ offset = 'Z' - 'A' + 1;
+
+ if (c >= 'a' && c <= 'z')
+ return c - 'a' + offset;
+
+ offset += 'z' - 'a' + 1;
+
+ if (c >= '0' && c <= '9')
+ return c - '0' + offset;
+
+ offset += '9' - '0' + 1;
+
+ if (c == '+')
+ return offset;
+
+ offset ++;
+
+ if (c == '/')
+ return offset;
+
+ return -EINVAL;
+}
+
+char *base64mem(const void *p, size_t l) {
+ char *r, *z;
+ const uint8_t *x;
+
+ /* three input bytes makes four output bytes, padding is added so we must round up */
+ z = r = malloc(4 * (l + 2) / 3 + 1);
+ if (!r)
+ return NULL;
+
+ for (x = p; x < (const uint8_t*) p + (l / 3) * 3; x += 3) {
+ /* x[0] == XXXXXXXX; x[1] == YYYYYYYY; x[2] == ZZZZZZZZ */
+ *(z++) = base64char(x[0] >> 2); /* 00XXXXXX */
+ *(z++) = base64char((x[0] & 3) << 4 | x[1] >> 4); /* 00XXYYYY */
+ *(z++) = base64char((x[1] & 15) << 2 | x[2] >> 6); /* 00YYYYZZ */
+ *(z++) = base64char(x[2] & 63); /* 00ZZZZZZ */
+ }
+
+ switch (l % 3) {
+ case 2:
+ *(z++) = base64char(x[0] >> 2); /* 00XXXXXX */
+ *(z++) = base64char((x[0] & 3) << 4 | x[1] >> 4); /* 00XXYYYY */
+ *(z++) = base64char((x[1] & 15) << 2); /* 00YYYY00 */
+ *(z++) = '=';
+
+ break;
+ case 1:
+ *(z++) = base64char(x[0] >> 2); /* 00XXXXXX */
+ *(z++) = base64char((x[0] & 3) << 4); /* 00XX0000 */
+ *(z++) = '=';
+ *(z++) = '=';
+
+ break;
+ }
+
+ *z = 0;
+ return r;
+}
+
+int unbase64mem(const char *p, size_t l, void **mem, size_t *_len) {
+ _cleanup_free_ uint8_t *r = NULL;
+ int a, b, c, d;
+ uint8_t *z;
+ const char *x;
+ size_t len;
+
+ assert(p);
+
+ /* padding ensures any base63 input has input divisible by 4 */
+ if (l % 4 != 0)
+ return -EINVAL;
+
+ /* strip the padding */
+ if (l > 0 && p[l - 1] == '=')
+ l --;
+ if (l > 0 && p[l - 1] == '=')
+ l --;
+
+ /* a group of four input bytes needs three output bytes, in case of
+ padding we need to add two or three extra bytes */
+ len = (l / 4) * 3 + (l % 4 ? (l % 4) - 1 : 0);
+
+ z = r = malloc(len + 1);
+ if (!r)
+ return -ENOMEM;
+
+ for (x = p; x < p + (l / 4) * 4; x += 4) {
+ /* a == 00XXXXXX; b == 00YYYYYY; c == 00ZZZZZZ; d == 00WWWWWW */
+ a = unbase64char(x[0]);
+ if (a < 0)
+ return -EINVAL;
+
+ b = unbase64char(x[1]);
+ if (b < 0)
+ return -EINVAL;
+
+ c = unbase64char(x[2]);
+ if (c < 0)
+ return -EINVAL;
+
+ d = unbase64char(x[3]);
+ if (d < 0)
+ return -EINVAL;
+
+ *(z++) = (uint8_t) a << 2 | (uint8_t) b >> 4; /* XXXXXXYY */
+ *(z++) = (uint8_t) b << 4 | (uint8_t) c >> 2; /* YYYYZZZZ */
+ *(z++) = (uint8_t) c << 6 | (uint8_t) d; /* ZZWWWWWW */
+ }
+
+ switch (l % 4) {
+ case 3:
+ a = unbase64char(x[0]);
+ if (a < 0)
+ return -EINVAL;
+
+ b = unbase64char(x[1]);
+ if (b < 0)
+ return -EINVAL;
+
+ c = unbase64char(x[2]);
+ if (c < 0)
+ return -EINVAL;
+
+ /* c == 00ZZZZ00 */
+ if (c & 3)
+ return -EINVAL;
+
+ *(z++) = (uint8_t) a << 2 | (uint8_t) b >> 4; /* XXXXXXYY */
+ *(z++) = (uint8_t) b << 4 | (uint8_t) c >> 2; /* YYYYZZZZ */
+
+ break;
+ case 2:
+ a = unbase64char(x[0]);
+ if (a < 0)
+ return -EINVAL;
+
+ b = unbase64char(x[1]);
+ if (b < 0)
+ return -EINVAL;
+
+ /* b == 00YY0000 */
+ if (b & 15)
+ return -EINVAL;
+
+ *(z++) = (uint8_t) a << 2 | (uint8_t) (b >> 4); /* XXXXXXYY */
+
+ break;
+ case 0:
+
+ break;
+ default:
+ return -EINVAL;
+ }
+
+ *z = 0;
+
+ *mem = r;
+ r = NULL;
+ *_len = len;
+
+ return 0;
+}
+