1193141Sdougb/* 2262706Serwin * Copyright (C) 2008, 2009, 2013, 2014 Internet Systems Consortium, Inc. ("ISC") 3193141Sdougb * 4193141Sdougb * Permission to use, copy, modify, and/or distribute this software for any 5193141Sdougb * purpose with or without fee is hereby granted, provided that the above 6193141Sdougb * copyright notice and this permission notice appear in all copies. 7193141Sdougb * 8193141Sdougb * THE SOFTWARE IS PROVIDED "AS IS" AND ISC DISCLAIMS ALL WARRANTIES WITH 9193141Sdougb * REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF MERCHANTABILITY 10193141Sdougb * AND FITNESS. IN NO EVENT SHALL ISC BE LIABLE FOR ANY SPECIAL, DIRECT, 11193141Sdougb * INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES WHATSOEVER RESULTING FROM 12193141Sdougb * LOSS OF USE, DATA OR PROFITS, WHETHER IN AN ACTION OF CONTRACT, NEGLIGENCE 13193141Sdougb * OR OTHER TORTIOUS ACTION, ARISING OUT OF OR IN CONNECTION WITH THE USE OR 14193141Sdougb * PERFORMANCE OF THIS SOFTWARE. 15193141Sdougb */ 16193141Sdougb 17234010Sdougb/* $Id: base32.c,v 1.6 2009/10/21 01:22:29 each Exp $ */ 18193141Sdougb 19193141Sdougb/*! \file */ 20193141Sdougb 21193141Sdougb#include <config.h> 22193141Sdougb 23193141Sdougb#include <isc/base32.h> 24193141Sdougb#include <isc/buffer.h> 25193141Sdougb#include <isc/lex.h> 26193141Sdougb#include <isc/region.h> 27193141Sdougb#include <isc/string.h> 28193141Sdougb#include <isc/util.h> 29193141Sdougb 30193141Sdougb#define RETERR(x) do { \ 31193141Sdougb isc_result_t _r = (x); \ 32193141Sdougb if (_r != ISC_R_SUCCESS) \ 33193141Sdougb return (_r); \ 34193141Sdougb } while (0) 35193141Sdougb 36193141Sdougb 37193141Sdougb/*@{*/ 38193141Sdougb/*! 39193141Sdougb * These static functions are also present in lib/dns/rdata.c. I'm not 40193141Sdougb * sure where they should go. -- bwelling 41193141Sdougb */ 42193141Sdougbstatic isc_result_t 43193141Sdougbstr_totext(const char *source, isc_buffer_t *target); 44193141Sdougb 45193141Sdougbstatic isc_result_t 46193141Sdougbmem_tobuffer(isc_buffer_t *target, void *base, unsigned int length); 47193141Sdougb 48193141Sdougb/*@}*/ 49193141Sdougb 50193141Sdougbstatic const char base32[] = 51193141Sdougb "ABCDEFGHIJKLMNOPQRSTUVWXYZ234567=abcdefghijklmnopqrstuvwxyz234567"; 52193141Sdougbstatic const char base32hex[] = 53193141Sdougb "0123456789ABCDEFGHIJKLMNOPQRSTUV=0123456789abcdefghijklmnopqrstuv"; 54193141Sdougb 55193141Sdougbstatic isc_result_t 56193141Sdougbbase32_totext(isc_region_t *source, int wordlength, const char *wordbreak, 57193141Sdougb isc_buffer_t *target, const char base[]) 58193141Sdougb{ 59193141Sdougb char buf[9]; 60193141Sdougb unsigned int loops = 0; 61193141Sdougb 62193141Sdougb if (wordlength >= 0 && wordlength < 8) 63193141Sdougb wordlength = 8; 64193141Sdougb 65193141Sdougb memset(buf, 0, sizeof(buf)); 66193141Sdougb while (source->length > 0) { 67193141Sdougb buf[0] = base[((source->base[0]>>3)&0x1f)]; /* 5 + */ 68193141Sdougb if (source->length == 1) { 69193141Sdougb buf[1] = base[(source->base[0]<<2)&0x1c]; 70193141Sdougb buf[2] = buf[3] = buf[4] = '='; 71193141Sdougb buf[5] = buf[6] = buf[7] = '='; 72193141Sdougb RETERR(str_totext(buf, target)); 73193141Sdougb break; 74193141Sdougb } 75193141Sdougb buf[1] = base[((source->base[0]<<2)&0x1c)| /* 3 = 8 */ 76193141Sdougb ((source->base[1]>>6)&0x03)]; /* 2 + */ 77193141Sdougb buf[2] = base[((source->base[1]>>1)&0x1f)]; /* 5 + */ 78193141Sdougb if (source->length == 2) { 79193141Sdougb buf[3] = base[(source->base[1]<<4)&0x10]; 80193141Sdougb buf[4] = buf[5] = buf[6] = buf[7] = '='; 81193141Sdougb RETERR(str_totext(buf, target)); 82193141Sdougb break; 83193141Sdougb } 84193141Sdougb buf[3] = base[((source->base[1]<<4)&0x10)| /* 1 = 8 */ 85193141Sdougb ((source->base[2]>>4)&0x0f)]; /* 4 + */ 86193141Sdougb if (source->length == 3) { 87193141Sdougb buf[4] = base[(source->base[2]<<1)&0x1e]; 88193141Sdougb buf[5] = buf[6] = buf[7] = '='; 89193141Sdougb RETERR(str_totext(buf, target)); 90193141Sdougb break; 91193141Sdougb } 92193141Sdougb buf[4] = base[((source->base[2]<<1)&0x1e)| /* 4 = 8 */ 93193141Sdougb ((source->base[3]>>7)&0x01)]; /* 1 + */ 94193141Sdougb buf[5] = base[((source->base[3]>>2)&0x1f)]; /* 5 + */ 95193141Sdougb if (source->length == 4) { 96193141Sdougb buf[6] = base[(source->base[3]<<3)&0x18]; 97193141Sdougb buf[7] = '='; 98193141Sdougb RETERR(str_totext(buf, target)); 99193141Sdougb break; 100193141Sdougb } 101193141Sdougb buf[6] = base[((source->base[3]<<3)&0x18)| /* 2 = 8 */ 102193141Sdougb ((source->base[4]>>5)&0x07)]; /* 3 + */ 103193141Sdougb buf[7] = base[source->base[4]&0x1f]; /* 5 = 8 */ 104193141Sdougb RETERR(str_totext(buf, target)); 105193141Sdougb isc_region_consume(source, 5); 106193141Sdougb 107193141Sdougb loops++; 108193141Sdougb if (source->length != 0 && wordlength >= 0 && 109193141Sdougb (int)((loops + 1) * 8) >= wordlength) 110193141Sdougb { 111193141Sdougb loops = 0; 112193141Sdougb RETERR(str_totext(wordbreak, target)); 113193141Sdougb } 114193141Sdougb } 115204619Sdougb if (source->length > 0) 116204619Sdougb isc_region_consume(source, source->length); 117193141Sdougb return (ISC_R_SUCCESS); 118193141Sdougb} 119193141Sdougb 120193141Sdougbisc_result_t 121193141Sdougbisc_base32_totext(isc_region_t *source, int wordlength, 122193141Sdougb const char *wordbreak, isc_buffer_t *target) 123193141Sdougb{ 124193141Sdougb return (base32_totext(source, wordlength, wordbreak, target, base32)); 125193141Sdougb} 126193141Sdougb 127193141Sdougbisc_result_t 128193141Sdougbisc_base32hex_totext(isc_region_t *source, int wordlength, 129193141Sdougb const char *wordbreak, isc_buffer_t *target) 130193141Sdougb{ 131193141Sdougb return (base32_totext(source, wordlength, wordbreak, target, 132193141Sdougb base32hex)); 133193141Sdougb} 134193141Sdougb 135193141Sdougb/*% 136193141Sdougb * State of a base32 decoding process in progress. 137193141Sdougb */ 138193141Sdougbtypedef struct { 139193141Sdougb int length; /*%< Desired length of binary data or -1 */ 140193141Sdougb isc_buffer_t *target; /*%< Buffer for resulting binary data */ 141193141Sdougb int digits; /*%< Number of buffered base32 digits */ 142193141Sdougb isc_boolean_t seen_end; /*%< True if "=" end marker seen */ 143193141Sdougb int val[8]; 144193141Sdougb const char *base; /*%< Which encoding we are using */ 145193141Sdougb int seen_32; /*%< Number of significant bytes if non zero */ 146193141Sdougb} base32_decode_ctx_t; 147193141Sdougb 148193141Sdougbstatic inline void 149193141Sdougbbase32_decode_init(base32_decode_ctx_t *ctx, int length, 150193141Sdougb const char base[], isc_buffer_t *target) 151193141Sdougb{ 152193141Sdougb ctx->digits = 0; 153193141Sdougb ctx->seen_end = ISC_FALSE; 154193141Sdougb ctx->seen_32 = 0; 155193141Sdougb ctx->length = length; 156193141Sdougb ctx->target = target; 157193141Sdougb ctx->base = base; 158193141Sdougb} 159193141Sdougb 160193141Sdougbstatic inline isc_result_t 161193141Sdougbbase32_decode_char(base32_decode_ctx_t *ctx, int c) { 162193141Sdougb char *s; 163193141Sdougb unsigned int last; 164193141Sdougb 165193141Sdougb if (ctx->seen_end) 166193141Sdougb return (ISC_R_BADBASE32); 167193141Sdougb if ((s = strchr(ctx->base, c)) == NULL) 168193141Sdougb return (ISC_R_BADBASE32); 169262706Serwin last = (unsigned int)(s - ctx->base); 170193141Sdougb /* 171193141Sdougb * Handle lower case. 172193141Sdougb */ 173193141Sdougb if (last > 32) 174193141Sdougb last -= 33; 175193141Sdougb /* 176193141Sdougb * Check that padding is contiguous. 177193141Sdougb */ 178193141Sdougb if (last != 32 && ctx->seen_32 != 0) 179193141Sdougb return (ISC_R_BADBASE32); 180193141Sdougb /* 181193141Sdougb * Check that padding starts at the right place and that 182193141Sdougb * bits that should be zero are. 183193141Sdougb * Record how many significant bytes in answer (seen_32). 184193141Sdougb */ 185193141Sdougb if (last == 32 && ctx->seen_32 == 0) 186193141Sdougb switch (ctx->digits) { 187193141Sdougb case 0: 188193141Sdougb case 1: 189193141Sdougb return (ISC_R_BADBASE32); 190193141Sdougb case 2: 191193141Sdougb if ((ctx->val[1]&0x03) != 0) 192193141Sdougb return (ISC_R_BADBASE32); 193193141Sdougb ctx->seen_32 = 1; 194193141Sdougb break; 195193141Sdougb case 3: 196193141Sdougb return (ISC_R_BADBASE32); 197193141Sdougb case 4: 198193141Sdougb if ((ctx->val[3]&0x0f) != 0) 199193141Sdougb return (ISC_R_BADBASE32); 200193141Sdougb ctx->seen_32 = 3; 201193141Sdougb break; 202193141Sdougb case 5: 203193141Sdougb if ((ctx->val[4]&0x01) != 0) 204193141Sdougb return (ISC_R_BADBASE32); 205193141Sdougb ctx->seen_32 = 3; 206193141Sdougb break; 207193141Sdougb case 6: 208193141Sdougb return (ISC_R_BADBASE32); 209193141Sdougb case 7: 210193141Sdougb if ((ctx->val[6]&0x07) != 0) 211193141Sdougb return (ISC_R_BADBASE32); 212193141Sdougb ctx->seen_32 = 4; 213193141Sdougb break; 214193141Sdougb } 215193141Sdougb /* 216193141Sdougb * Zero fill pad values. 217193141Sdougb */ 218193141Sdougb ctx->val[ctx->digits++] = (last == 32) ? 0 : last; 219193141Sdougb 220193141Sdougb if (ctx->digits == 8) { 221193141Sdougb int n = 5; 222193141Sdougb unsigned char buf[5]; 223193141Sdougb 224193141Sdougb if (ctx->seen_32 != 0) { 225193141Sdougb ctx->seen_end = ISC_TRUE; 226193141Sdougb n = ctx->seen_32; 227193141Sdougb } 228193141Sdougb buf[0] = (ctx->val[0]<<3)|(ctx->val[1]>>2); 229193141Sdougb buf[1] = (ctx->val[1]<<6)|(ctx->val[2]<<1)|(ctx->val[3]>>4); 230193141Sdougb buf[2] = (ctx->val[3]<<4)|(ctx->val[4]>>1); 231193141Sdougb buf[3] = (ctx->val[4]<<7)|(ctx->val[5]<<2)|(ctx->val[6]>>3); 232193141Sdougb buf[4] = (ctx->val[6]<<5)|(ctx->val[7]); 233193141Sdougb RETERR(mem_tobuffer(ctx->target, buf, n)); 234193141Sdougb if (ctx->length >= 0) { 235193141Sdougb if (n > ctx->length) 236193141Sdougb return (ISC_R_BADBASE32); 237193141Sdougb else 238193141Sdougb ctx->length -= n; 239193141Sdougb } 240193141Sdougb ctx->digits = 0; 241193141Sdougb } 242193141Sdougb return (ISC_R_SUCCESS); 243193141Sdougb} 244193141Sdougb 245193141Sdougbstatic inline isc_result_t 246193141Sdougbbase32_decode_finish(base32_decode_ctx_t *ctx) { 247193141Sdougb if (ctx->length > 0) 248193141Sdougb return (ISC_R_UNEXPECTEDEND); 249193141Sdougb if (ctx->digits != 0) 250193141Sdougb return (ISC_R_BADBASE32); 251193141Sdougb return (ISC_R_SUCCESS); 252193141Sdougb} 253193141Sdougb 254193141Sdougbstatic isc_result_t 255193141Sdougbbase32_tobuffer(isc_lex_t *lexer, const char base[], isc_buffer_t *target, 256193141Sdougb int length) 257193141Sdougb{ 258193141Sdougb base32_decode_ctx_t ctx; 259193141Sdougb isc_textregion_t *tr; 260193141Sdougb isc_token_t token; 261193141Sdougb isc_boolean_t eol; 262193141Sdougb 263193141Sdougb base32_decode_init(&ctx, length, base, target); 264193141Sdougb 265193141Sdougb while (!ctx.seen_end && (ctx.length != 0)) { 266193141Sdougb unsigned int i; 267193141Sdougb 268193141Sdougb if (length > 0) 269193141Sdougb eol = ISC_FALSE; 270193141Sdougb else 271193141Sdougb eol = ISC_TRUE; 272193141Sdougb RETERR(isc_lex_getmastertoken(lexer, &token, 273193141Sdougb isc_tokentype_string, eol)); 274193141Sdougb if (token.type != isc_tokentype_string) 275193141Sdougb break; 276193141Sdougb tr = &token.value.as_textregion; 277193141Sdougb for (i = 0; i < tr->length; i++) 278193141Sdougb RETERR(base32_decode_char(&ctx, tr->base[i])); 279193141Sdougb } 280193141Sdougb if (ctx.length < 0 && !ctx.seen_end) 281193141Sdougb isc_lex_ungettoken(lexer, &token); 282193141Sdougb RETERR(base32_decode_finish(&ctx)); 283193141Sdougb return (ISC_R_SUCCESS); 284193141Sdougb} 285193141Sdougb 286193141Sdougbisc_result_t 287193141Sdougbisc_base32_tobuffer(isc_lex_t *lexer, isc_buffer_t *target, int length) { 288193141Sdougb return (base32_tobuffer(lexer, base32, target, length)); 289193141Sdougb} 290193141Sdougb 291193141Sdougbisc_result_t 292193141Sdougbisc_base32hex_tobuffer(isc_lex_t *lexer, isc_buffer_t *target, int length) { 293193141Sdougb return (base32_tobuffer(lexer, base32hex, target, length)); 294193141Sdougb} 295193141Sdougb 296193141Sdougbstatic isc_result_t 297193141Sdougbbase32_decodestring(const char *cstr, const char base[], isc_buffer_t *target) { 298193141Sdougb base32_decode_ctx_t ctx; 299193141Sdougb 300193141Sdougb base32_decode_init(&ctx, -1, base, target); 301193141Sdougb for (;;) { 302193141Sdougb int c = *cstr++; 303193141Sdougb if (c == '\0') 304193141Sdougb break; 305193141Sdougb if (c == ' ' || c == '\t' || c == '\n' || c== '\r') 306193141Sdougb continue; 307193141Sdougb RETERR(base32_decode_char(&ctx, c)); 308193141Sdougb } 309193141Sdougb RETERR(base32_decode_finish(&ctx)); 310193141Sdougb return (ISC_R_SUCCESS); 311193141Sdougb} 312193141Sdougb 313193141Sdougbisc_result_t 314193141Sdougbisc_base32_decodestring(const char *cstr, isc_buffer_t *target) { 315193141Sdougb return (base32_decodestring(cstr, base32, target)); 316193141Sdougb} 317193141Sdougb 318193141Sdougbisc_result_t 319193141Sdougbisc_base32hex_decodestring(const char *cstr, isc_buffer_t *target) { 320193141Sdougb return (base32_decodestring(cstr, base32hex, target)); 321193141Sdougb} 322193141Sdougb 323193141Sdougbstatic isc_result_t 324193141Sdougbbase32_decoderegion(isc_region_t *source, const char base[], isc_buffer_t *target) { 325193141Sdougb base32_decode_ctx_t ctx; 326193141Sdougb 327193141Sdougb base32_decode_init(&ctx, -1, base, target); 328193141Sdougb while (source->length != 0) { 329193141Sdougb int c = *source->base; 330193141Sdougb RETERR(base32_decode_char(&ctx, c)); 331193141Sdougb isc_region_consume(source, 1); 332193141Sdougb } 333193141Sdougb RETERR(base32_decode_finish(&ctx)); 334193141Sdougb return (ISC_R_SUCCESS); 335193141Sdougb} 336193141Sdougb 337193141Sdougbisc_result_t 338193141Sdougbisc_base32_decoderegion(isc_region_t *source, isc_buffer_t *target) { 339193141Sdougb return (base32_decoderegion(source, base32, target)); 340193141Sdougb} 341193141Sdougb 342193141Sdougbisc_result_t 343193141Sdougbisc_base32hex_decoderegion(isc_region_t *source, isc_buffer_t *target) { 344193141Sdougb return (base32_decoderegion(source, base32hex, target)); 345193141Sdougb} 346193141Sdougb 347193141Sdougbstatic isc_result_t 348193141Sdougbstr_totext(const char *source, isc_buffer_t *target) { 349193141Sdougb unsigned int l; 350193141Sdougb isc_region_t region; 351193141Sdougb 352193141Sdougb isc_buffer_availableregion(target, ®ion); 353193141Sdougb l = strlen(source); 354193141Sdougb 355193141Sdougb if (l > region.length) 356193141Sdougb return (ISC_R_NOSPACE); 357193141Sdougb 358262706Serwin memmove(region.base, source, l); 359193141Sdougb isc_buffer_add(target, l); 360193141Sdougb return (ISC_R_SUCCESS); 361193141Sdougb} 362193141Sdougb 363193141Sdougbstatic isc_result_t 364193141Sdougbmem_tobuffer(isc_buffer_t *target, void *base, unsigned int length) { 365193141Sdougb isc_region_t tr; 366193141Sdougb 367193141Sdougb isc_buffer_availableregion(target, &tr); 368193141Sdougb if (length > tr.length) 369193141Sdougb return (ISC_R_NOSPACE); 370262706Serwin memmove(tr.base, base, length); 371193141Sdougb isc_buffer_add(target, length); 372193141Sdougb return (ISC_R_SUCCESS); 373193141Sdougb} 374