X-Git-Url: https://pd.if.org/git/?a=blobdiff_plain;f=crypto%2Fbase64.c;fp=crypto%2Fbase64.c;h=1b944f4f5874fe2db59cadd3762ccb1eb2190128;hb=66bc25938679f1d6a1d1200f329093d82a5e99b4;hp=0000000000000000000000000000000000000000;hpb=a52ee0733f420ca20224049260d6fc5cf7d8f621;p=zpackage

diff --git a/crypto/base64.c b/crypto/base64.c
new file mode 100644
index 0000000..1b944f4
--- /dev/null
+++ b/crypto/base64.c
@@ -0,0 +1,82 @@
+#define _POSIX_C_SOURCE 200809L
+
+#include <stdint.h>
+#include <stdlib.h>
+
+#define WHITESPACE 64
+#define EQUALS     65
+#define INVALID    66
+
+static const unsigned char d[] = {
+	66, 66, 66, 66, 66, 66, 66, 66, 66, 66, 64, 66, 66, 66, 66, 66, 66,
+	    66, 66, 66, 66, 66, 66, 66, 66,
+	66, 66, 66, 66, 66, 66, 66, 66, 66, 66, 66, 66, 66, 66, 66, 66, 66,
+	    66, 62, 66, 66, 66, 63, 52, 53,
+	54, 55, 56, 57, 58, 59, 60, 61, 66, 66, 66, 65, 66, 66, 66, 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, 66,
+	    66, 66, 66, 66, 66, 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, 66, 66,
+	66, 66, 66, 66, 66, 66, 66, 66, 66, 66, 66, 66, 66, 66, 66, 66, 66,
+	    66, 66, 66, 66, 66, 66, 66, 66,
+	66, 66, 66, 66, 66, 66, 66, 66, 66, 66, 66, 66, 66, 66, 66, 66, 66,
+	    66, 66, 66, 66, 66, 66, 66, 66,
+	66, 66, 66, 66, 66, 66, 66, 66, 66, 66, 66, 66, 66, 66, 66, 66, 66,
+	    66, 66, 66, 66, 66, 66, 66, 66,
+	66, 66, 66, 66, 66, 66, 66, 66, 66, 66, 66, 66, 66, 66, 66, 66, 66,
+	    66, 66, 66, 66, 66, 66, 66, 66,
+	66, 66, 66, 66, 66, 66, 66, 66, 66, 66, 66, 66, 66, 66, 66, 66, 66,
+	    66, 66, 66, 66, 66, 66, 66, 66,
+	66, 66, 66, 66, 66, 66
+};
+
+int base64decode(const char *in, size_t inLen, unsigned char *out,
+		 size_t *outLen) {
+	const char *end = in + inLen;
+	char iter = 0;
+	uint32_t buf = 0;
+	size_t len = 0;
+
+	while (in < end) {
+		unsigned char c = d[(int)(*in++)];
+
+		switch (c) {
+		case WHITESPACE:
+			continue;	/* skip whitespace */
+		case INVALID:
+			return 0;	/* invalid input, return error */
+		case EQUALS:	/* pad character, end of data */
+			in = end;
+			continue;
+		default:
+			buf = buf << 6 | c;
+			iter++;	// increment the number of iteration
+			/* If the buffer is full, split it into bytes */
+			if (iter == 4) {
+				if ((len += 3) > *outLen)
+					return 0;	/* buffer overflow */
+				*(out++) = (buf >> 16) & 255;
+				*(out++) = (buf >> 8) & 255;
+				*(out++) = buf & 255;
+				buf = 0;
+				iter = 0;
+
+			}
+		}
+	}
+
+	if (iter == 3) {
+		if ((len += 2) > *outLen)
+			return 0;	/* buffer overflow */
+		*(out++) = (buf >> 10) & 255;
+		*(out++) = (buf >> 2) & 255;
+	} else if (iter == 2) {
+		if (++len > *outLen)
+			return 0;	/* buffer overflow */
+		*(out++) = (buf >> 4) & 255;
+	}
+
+	*outLen = len;		/* modify to reflect the actual output size */
+	return 1;
+}