[sr-dev] git:master:57d131bc: core: functions to encode/decode base64-url

Module: kamailio Branch: master Commit: 57d131bc26523d4a87d60b9e3fa96079030efa88 URL: https://github.com/kamailio/kamailio/commit/57d131bc26523d4a87d60b9e3fa9607… Author: Daniel-Constantin Mierla &lt;miconda(a)gmail.com&gt; Committer: Daniel-Constantin Mierla &lt;miconda(a)gmail.com&gt; Date: 2020-03-06T17:45:43+01:00 core: functions to encode/decode base64-url --- Modified: src/core/basex.c Modified: src/core/basex.h --- Diff: https://github.com/kamailio/kamailio/commit/57d131bc26523d4a87d60b9e3fa9607… Patch: https://github.com/kamailio/kamailio/commit/57d131bc26523d4a87d60b9e3fa9607… --- diff --git a/src/core/basex.c b/src/core/basex.c index 592ea0cd96..ce5f7543a1 100644 --- a/src/core/basex.c +++ b/src/core/basex.c @@ -387,3 +387,124 @@ char* b58_encode(char *b58, int *b58sz, char *data, int binsz) return b58; } + +/* base64-url encoding table (RFC 4648 document) */ +static const char _ksr_b64url_encmap[] = "ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz0123456789-_"; + +/* base64-url decoding table */ +static const int _ksr_b64url_decmap[] = { + -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, -1, -1, 0x3E, -1, -1, + 0x34, 0x35, 0x36, 0x37, 0x38, 0x39, 0x3A, 0x3B, + 0x3C, 0x3D, -1, -1, -1, -1, -1, -1, + -1, 0x00, 0x01, 0x02, 0x03, 0x04, 0x05, 0x06, + 0x07, 0x08, 0x09, 0x0A, 0x0B, 0x0C, 0x0D, 0x0E, + 0x0F, 0x10, 0x11, 0x12, 0x13, 0x14, 0x15, 0x16, + 0x17, 0x18, 0x19, -1, -1, -1, -1, 0x3F, + -1, 0x1A, 0x1B, 0x1C, 0x1D, 0x1E, 0x1F, 0x20, + 0x21, 0x22, 0x23, 0x24, 0x25, 0x26, 0x27, 0x28, + 0x29, 0x2A, 0x2B, 0x2C, 0x2D, 0x2E, 0x2F, 0x30, + 0x31, 0x32, 0x33, -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, -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, -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, -1, -1, -1, -1 +}; + +int base64url_encode(char *in, int ilen, char *out, int osize) +{ + int left; + int idx; + int i; + int r; + char *p; + int block; + int olen; + + olen = (((ilen+2)/3)<<2); + if (olen >= osize) { + LM_ERR("not enough output buffer size %d - need %d\n", osize, olen+1); + return -1; + } + memset(out, 0, (olen+1)*sizeof(char)); + + p = out; + for(idx=0; idx<ilen; idx+=3) { + left = ilen - idx - 1 ; + left = (left>1)?2:left; + + block = 0; + for(i=0, r=16; i<=left; i++, r-=8) + block += ((unsigned char)in[idx+i]) << r; + + *(p++) = _ksr_b64url_encmap[(block >> 18) & 0x3f]; + *(p++) = _ksr_b64url_encmap[(block >> 12) & 0x3f]; + *(p++) = (left>0)?_ksr_b64url_encmap[(block >> 6) & 0x3f]:'='; + *(p++) = (left>1)?_ksr_b64url_encmap[block & 0x3f]:'='; + } + + return olen; +} + +int base64url_dec(char *in, int ilen, char *out, int osize) +{ + int n; + int block; + int idx; + int i; + int j; + int end; + char c; + int olen; + + for(n=0,i=ilen-1; in[i]=='='; i--) + n++; + + olen = ((ilen * 6) >> 3) - n; + + if (olen<=0) { + LM_ERR("invalid olen parameter calculated, can't continue %d\n", olen); + return -1; + } + + if(olen >= osize) { + LM_ERR("not enough output buffer size %d - need %d\n", osize, olen+1); + return -1; + } + memset(out, 0, (olen+1)*sizeof(char)); + + end = ilen - n; + for(i=0, idx=0; i<end; idx+=3) { + block = 0; + for(j=0; j<4 && i<end ; j++) { + c = _ksr_b64url_decmap[(int)in[i++]]; + if(c<0) { + LM_ERR("invalid input string\"%.*s\"\n", ilen, in); + return -1; + } + block += c << (18 - 6*j); + } + + for(j=0, n=16; j<3 && idx+j<olen; j++, n-=8) + out[idx+j] = (char)((block >> n) & 0xff); + } + + return olen; +} + diff --git a/src/core/basex.h b/src/core/basex.h index 1c5af1c780..8181e6f512 100644 --- a/src/core/basex.h +++ b/src/core/basex.h @@ -864,4 +864,7 @@ int init_basex(void); char* b58_encode(char *b58, int *b58sz, char *data, int binsz); char* b58_decode(char *outb, int *outbszp, char *b58, int b58sz); +int base64url_enc(char *in, int ilen, char *out, int osize); +int base64url_dec(char *in, int ilen, char *out, int osize); + #endif /* _basex_h */