mirror of https://github.com/waku-org/nwaku.git
59 lines
1.0 KiB
C
59 lines
1.0 KiB
C
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#include "base64.h"
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// Base64 encoding
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// source: https://nachtimwald.com/2017/11/18/base64-encode-and-decode-in-c/
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size_t b64_encoded_size(size_t inlen)
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{
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size_t ret;
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ret = inlen;
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if (inlen % 3 != 0)
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ret += 3 - (inlen % 3);
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ret /= 3;
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ret *= 4;
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return ret;
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}
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const char b64chars[] = "ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz0123456789+/";
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char *b64_encode(const unsigned char *in, size_t len)
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{
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char *out;
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size_t elen;
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size_t i;
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size_t j;
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size_t v;
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if (in == NULL || len == 0)
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return NULL;
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elen = b64_encoded_size(len);
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out = malloc(elen+1);
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out[elen] = '\0';
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for (i=0, j=0; i<len; i+=3, j+=4) {
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v = in[i];
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v = i+1 < len ? v << 8 | in[i+1] : v << 8;
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v = i+2 < len ? v << 8 | in[i+2] : v << 8;
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out[j] = b64chars[(v >> 18) & 0x3F];
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out[j+1] = b64chars[(v >> 12) & 0x3F];
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if (i+1 < len) {
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out[j+2] = b64chars[(v >> 6) & 0x3F];
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} else {
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out[j+2] = '=';
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}
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if (i+2 < len) {
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out[j+3] = b64chars[v & 0x3F];
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} else {
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out[j+3] = '=';
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}
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}
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return out;
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}
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// End of Base64 encoding
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