/* * Copyright (c) 2020 Kungliga Tekniska Högskolan * (Royal Institute of Technology, Stockholm, Sweden). * All rights reserved. * * Redistribution and use in source and binary forms, with or without * modification, are permitted provided that the following conditions * are met: * * 1. Redistributions of source code must retain the above copyright * notice, this list of conditions and the following disclaimer. * * 2. Redistributions in binary form must reproduce the above copyright * notice, this list of conditions and the following disclaimer in the * documentation and/or other materials provided with the distribution. * * 3. Neither the name of the Institute nor the names of its contributors * may be used to endorse or promote products derived from this software * without specific prior written permission. * * THIS SOFTWARE IS PROVIDED BY THE INSTITUTE AND CONTRIBUTORS ``AS IS'' AND * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE * ARE DISCLAIMED. IN NO EVENT SHALL THE INSTITUTE OR CONTRIBUTORS BE LIABLE * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF * SUCH DAMAGE. */ #include #include #include #include #include #ifdef TEST #include #include #include #endif #include "base32.h" #include "roken.h" static const unsigned char base32_chars[] = "ABCDEFGHIJKLMNOPQRSTUVWXYZ234567"; static const unsigned char base32op_chars[] = "0123456789ABCDEFGHIJKLMNOPQRSTUV"; ROKEN_LIB_FUNCTION int ROKEN_LIB_CALL rk_base32_encode(const void *data, int size, char **str, enum rk_base32_flags flags) { const unsigned char *chars = (flags & RK_BASE32_FLAG_PRESERVE_ORDER) ? base32op_chars : base32_chars; uint64_t c; char *s, *p; int i; const unsigned char *q; if (size > INT_MAX/8 || size < 0) { *str = NULL; errno = ERANGE; return -1; } p = s = malloc(((size + 5 - 1) / 5) * 8 + 1); if (p == NULL) { *str = NULL; return -1; } q = (const unsigned char *) data; for (i = 0; i < size;) { /* 5 bytes of input will give us 8 output bytes' worth of bits */ c = q[i++]; c <<= 8; if (i < size) c += q[i]; i++; c <<= 8; if (i < size) c += q[i]; i++; c <<= 8; if (i < size) c += q[i]; i++; c <<= 8; if (i < size) c += q[i]; i++; p[0] = chars[(c & 0x00000000f800000000ULL) >> 35]; p[1] = chars[(c & 0x0000000007c0000000ULL) >> 30]; p[2] = chars[(c & 0x00000000003e000000ULL) >> 25]; p[3] = chars[(c & 0x000000000001f00000ULL) >> 20]; p[4] = chars[(c & 0x0000000000000f8000ULL) >> 15]; p[5] = chars[(c & 0x000000000000007c00ULL) >> 10]; p[6] = chars[(c & 0x0000000000000003e0ULL) >> 5]; p[7] = chars[(c & 0x00000000000000001fULL) >> 0]; switch (i - size) { case 4: p[2] = p[3] = '='; fallthrough; case 3: p[4] = '='; fallthrough; case 2: p[5] = p[6] = '='; fallthrough; case 1: p[7] = '='; fallthrough; default: break; } p += 8; } *p = 0; *str = s; return (int) strlen(s); } #define DECODE_ERROR ((uint64_t)-1) static int pos(char c, int preserve_order) { /* EBCDIC need not apply */ if (preserve_order) { if (c >= '0' && c <= '9') return c - '0'; if (c >= 'A' && c <= 'V') return c - 'A' + ('9' - '0') + 1; } else { if (c >= 'A' && c <= 'Z') return c - 'A'; if (c >= '2' && c <= '7') return c - '2' + ('Z' - 'A') + 1; } return -1; } static uint64_t token_decode(const char *token, enum rk_base32_flags flags) { uint64_t marker = 0; uint64_t val = 0; int preserve_order = !!(flags & RK_BASE32_FLAG_PRESERVE_ORDER); int i, c; if (strlen(token) < 8) return DECODE_ERROR; for (i = 0; i < 8; i++) { val <<= 5; if (token[i] == '=') marker++; else if (marker) return DECODE_ERROR; else if ((c = pos(token[i], preserve_order)) == -1 && (flags & RK_BASE32_FLAG_STOP_ON_GARBAGE)) break; else if (c == -1) return DECODE_ERROR; else val |= c; } if (marker > 6) return DECODE_ERROR; return (marker << 40) | val; } ROKEN_LIB_FUNCTION int ROKEN_LIB_CALL rk_base32_decode(const char *str, void *data, enum rk_base32_flags flags) { const char *p; unsigned char *q; int preserve_order = !!(flags & RK_BASE32_FLAG_PRESERVE_ORDER); q = data; for (p = str; *p && (*p == '=' || pos(*p, preserve_order) != -1); p += 8) { uint64_t val = token_decode(p, flags); uint64_t marker = (val >> 40) & 0xffULL; if (val == DECODE_ERROR) { errno = EINVAL; return -1; } *q++ = (val >> 32) & 0xffULL; if (marker < 6) *q++ = (val >> 24) & 0xffULL; if (marker < 4) *q++ = (val >> 16) & 0xffULL; if (marker < 3) *q++ = (val >> 8) & 0xffULL; if (marker < 1) *q++ = val & 0xffULL; if (marker && !(flags & RK_BASE32_FLAG_INTERIOR_PADDING_OK)) break; } if (q - (unsigned char *) data > INT_MAX) { errno = EOVERFLOW; return -1; } return q - (unsigned char *) data; } #ifdef TEST static int interior_padding_ok; static int preserve_order_flag; static int stop_on_garbage; static int decode_flag; static int help_flag; /* * The short options are compatible with a subset of the FreeBSD contrib * vis(1). Heimdal additions have long option names only. */ static struct getargs args[] = { { "preserve-order", 'P', arg_flag, &preserve_order_flag, "Use order-preserving alphabet", NULL }, { "interior-padding-ok", 'O', arg_flag, &interior_padding_ok, "Decode concatenated padded base32 strings as one", NULL }, { "stop-on-garbage", 'G', arg_flag, &stop_on_garbage, "Do not error on garbage", NULL }, { "decode", 'd', arg_flag, &decode_flag, "Decode", NULL }, { "help", 'h', arg_flag, &help_flag, "Print help message", NULL }, }; static size_t num_args = sizeof(args)/sizeof(args[0]); int main(int argc, char **argv) { enum rk_base32_flags flags = 0; unsigned char *buf = NULL; size_t buflen = 0; size_t bufsz = 0; int goptind = 0; int ret; setprogname("rkbase32"); if (getarg(args, num_args, argc, argv, &goptind) || help_flag) { arg_printusage(args, num_args, NULL, "FILE | -"); return help_flag ? 0 : 1; } argc -= goptind; argv += goptind; flags |= preserve_order_flag ? RK_BASE32_FLAG_PRESERVE_ORDER : 0; flags |= interior_padding_ok ? RK_BASE32_FLAG_INTERIOR_PADDING_OK : 0; flags |= stop_on_garbage ? RK_BASE32_FLAG_STOP_ON_GARBAGE : 0; if (help_flag) return arg_printusage(args, num_args, NULL, "FILE | -- -"), 0; if (argc != 1) return arg_printusage(args, num_args, NULL, "FILE | -- -"), 1; if (strcmp(argv[0], "-") == 0) { unsigned char *tmp; unsigned char d[4096]; size_t bytes; while (!feof(stdin) && !ferror(stdin)) { bytes = fread(d, 1, sizeof(d), stdin); if (bytes == 0) continue; if (buflen + bytes > bufsz) { if ((tmp = realloc(buf, bufsz + (bufsz >> 2) + sizeof(d))) == NULL) err(1, "Could not read stdin"); buf = tmp; bufsz = bufsz + (bufsz >> 2) + sizeof(d); } memcpy(buf + buflen, d, bytes); buflen += bytes; } if (ferror(stdin)) err(1, "Could not read stdin"); } else { void *d; if ((errno = rk_undumpdata(argv[0], &d, &bufsz))) err(1, "Could not read %s", argv[0]); buflen = bufsz; buf = d; } if (decode_flag) { unsigned char *d; if (buflen == bufsz) { unsigned char *tmp; if ((tmp = realloc(buf, bufsz + 1)) == NULL) err(1, "Could not decode data"); buf = tmp; bufsz++; } buf[buflen] = '\0'; if ((d = malloc(buflen * 5 / 8 + 4)) == NULL) err(1, "Could not decode data"); if ((ret = rk_base32_decode((const char *)buf, d, flags)) < 0) err(1, "Could not decode data"); if (fwrite(d, ret, 1, stdout) != 1) err(1, "Could not write decoded data"); free(d); } else if (buf) { /* buf can be NULL if we read from an empty file */ char *e; if ((ret = rk_base32_encode(buf, buflen, &e, flags)) < 0) err(1, "Could not encode data"); if (fwrite(e, ret, 1, stdout) != 1) err(1, "Could not write decoded data"); free(e); if (fwrite("\n", 1, 1, stdout) != 1) err(1, "Could not write decoded data"); } free(buf); return 0; } #endif