mirror of
https://github.com/jart/cosmopolitan.git
synced 2025-01-31 03:27:39 +00:00
353 lines
10 KiB
C
353 lines
10 KiB
C
/*-*- mode:c;indent-tabs-mode:t;c-basic-offset:8;tab-width:8;coding:utf-8 -*-│
|
|
│ vi: set noet ft=c ts=8 sw=8 fenc=utf-8 :vi │
|
|
╚──────────────────────────────────────────────────────────────────────────────╝
|
|
│ │
|
|
│ Musl Libc │
|
|
│ Copyright © 2005-2014 Rich Felker, et al. │
|
|
│ │
|
|
│ Permission is hereby granted, free of charge, to any person obtaining │
|
|
│ a copy of this software and associated documentation files (the │
|
|
│ "Software"), to deal in the Software without restriction, including │
|
|
│ without limitation the rights to use, copy, modify, merge, publish, │
|
|
│ distribute, sublicense, and/or sell copies of the Software, and to │
|
|
│ permit persons to whom the Software is furnished to do so, subject to │
|
|
│ the following conditions: │
|
|
│ │
|
|
│ The above copyright notice and this permission notice shall be │
|
|
│ included in all copies or substantial portions of the Software. │
|
|
│ │
|
|
│ THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, │
|
|
│ EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF │
|
|
│ MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. │
|
|
│ IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY │
|
|
│ CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, │
|
|
│ TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE │
|
|
│ SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE. │
|
|
│ │
|
|
╚─────────────────────────────────────────────────────────────────────────────*/
|
|
#include "libc/mem/alg.h"
|
|
#include "libc/calls/calls.h"
|
|
#include "libc/fmt/conv.h"
|
|
#include "libc/limits.h"
|
|
#include "libc/literal.h"
|
|
#include "libc/mem/mem.h"
|
|
#include "libc/nexgen32e/nexgen32e.h"
|
|
#include "libc/stdio/rand.h"
|
|
#include "libc/runtime/runtime.h"
|
|
#include "libc/stdio/stdio.h"
|
|
#include "libc/temp.h"
|
|
#include "libc/str/str.h"
|
|
#include "libc/sysv/consts/exit.h"
|
|
#include "third_party/gdtoa/gdtoa.h"
|
|
#include "libc/ctype.h"
|
|
#include "third_party/musl/crypt.internal.h"
|
|
__static_yoink("musl_libc_notice");
|
|
|
|
#pragma GCC diagnostic ignored "-Wmissing-braces"
|
|
|
|
/*
|
|
* public domain sha256 crypt implementation
|
|
*
|
|
* original sha crypt design: http://people.redhat.com/drepper/SHA-crypt.txt
|
|
* in this implementation at least 32bit int is assumed,
|
|
* key length is limited, the $5$ prefix is mandatory, '\n' and ':' is rejected
|
|
* in the salt and rounds= setting must contain a valid iteration count,
|
|
* on error "*" is returned.
|
|
*/
|
|
|
|
/* public domain sha256 implementation based on fips180-3 */
|
|
|
|
struct sha256 {
|
|
uint64_t len; /* processed message length */
|
|
uint32_t h[8]; /* hash state */
|
|
uint8_t buf[64]; /* message block buffer */
|
|
};
|
|
|
|
static uint32_t ror(uint32_t n, int k) { return (n >> k) | (n << (32-k)); }
|
|
#define Ch(x,y,z) (z ^ (x & (y ^ z)))
|
|
#define Maj(x,y,z) ((x & y) | (z & (x | y)))
|
|
#define S0(x) (ror(x,2) ^ ror(x,13) ^ ror(x,22))
|
|
#define S1(x) (ror(x,6) ^ ror(x,11) ^ ror(x,25))
|
|
#define R0(x) (ror(x,7) ^ ror(x,18) ^ (x>>3))
|
|
#define R1(x) (ror(x,17) ^ ror(x,19) ^ (x>>10))
|
|
|
|
static void processblock(struct sha256 *s, const uint8_t *buf)
|
|
{
|
|
uint32_t W[64], t1, t2, a, b, c, d, e, f, g, h;
|
|
int i;
|
|
|
|
for (i = 0; i < 16; i++) {
|
|
W[i] = (uint32_t)buf[4*i]<<24;
|
|
W[i] |= (uint32_t)buf[4*i+1]<<16;
|
|
W[i] |= (uint32_t)buf[4*i+2]<<8;
|
|
W[i] |= buf[4*i+3];
|
|
}
|
|
for (; i < 64; i++)
|
|
W[i] = R1(W[i-2]) + W[i-7] + R0(W[i-15]) + W[i-16];
|
|
a = s->h[0];
|
|
b = s->h[1];
|
|
c = s->h[2];
|
|
d = s->h[3];
|
|
e = s->h[4];
|
|
f = s->h[5];
|
|
g = s->h[6];
|
|
h = s->h[7];
|
|
for (i = 0; i < 64; i++) {
|
|
t1 = h + S1(e) + Ch(e,f,g) + kSha256[i] + W[i];
|
|
t2 = S0(a) + Maj(a,b,c);
|
|
h = g;
|
|
g = f;
|
|
f = e;
|
|
e = d + t1;
|
|
d = c;
|
|
c = b;
|
|
b = a;
|
|
a = t1 + t2;
|
|
}
|
|
s->h[0] += a;
|
|
s->h[1] += b;
|
|
s->h[2] += c;
|
|
s->h[3] += d;
|
|
s->h[4] += e;
|
|
s->h[5] += f;
|
|
s->h[6] += g;
|
|
s->h[7] += h;
|
|
}
|
|
|
|
static void pad(struct sha256 *s)
|
|
{
|
|
unsigned r = s->len % 64;
|
|
|
|
s->buf[r++] = 0x80;
|
|
if (r > 56) {
|
|
memset(s->buf + r, 0, 64 - r);
|
|
r = 0;
|
|
processblock(s, s->buf);
|
|
}
|
|
memset(s->buf + r, 0, 56 - r);
|
|
s->len *= 8;
|
|
s->buf[56] = s->len >> 56;
|
|
s->buf[57] = s->len >> 48;
|
|
s->buf[58] = s->len >> 40;
|
|
s->buf[59] = s->len >> 32;
|
|
s->buf[60] = s->len >> 24;
|
|
s->buf[61] = s->len >> 16;
|
|
s->buf[62] = s->len >> 8;
|
|
s->buf[63] = s->len;
|
|
processblock(s, s->buf);
|
|
}
|
|
|
|
static void sha256_init(struct sha256 *s)
|
|
{
|
|
s->len = 0;
|
|
s->h[0] = 0x6a09e667;
|
|
s->h[1] = 0xbb67ae85;
|
|
s->h[2] = 0x3c6ef372;
|
|
s->h[3] = 0xa54ff53a;
|
|
s->h[4] = 0x510e527f;
|
|
s->h[5] = 0x9b05688c;
|
|
s->h[6] = 0x1f83d9ab;
|
|
s->h[7] = 0x5be0cd19;
|
|
}
|
|
|
|
static void sha256_sum(struct sha256 *s, uint8_t *md)
|
|
{
|
|
int i;
|
|
|
|
pad(s);
|
|
for (i = 0; i < 8; i++) {
|
|
md[4*i] = s->h[i] >> 24;
|
|
md[4*i+1] = s->h[i] >> 16;
|
|
md[4*i+2] = s->h[i] >> 8;
|
|
md[4*i+3] = s->h[i];
|
|
}
|
|
}
|
|
|
|
static void sha256_update(struct sha256 *s, const void *m, unsigned long len)
|
|
{
|
|
const uint8_t *p = m;
|
|
unsigned r = s->len % 64;
|
|
|
|
s->len += len;
|
|
if (r) {
|
|
if (len < 64 - r) {
|
|
memcpy(s->buf + r, p, len);
|
|
return;
|
|
}
|
|
memcpy(s->buf + r, p, 64 - r);
|
|
len -= 64 - r;
|
|
p += 64 - r;
|
|
processblock(s, s->buf);
|
|
}
|
|
for (; len >= 64; len -= 64, p += 64)
|
|
processblock(s, p);
|
|
memcpy(s->buf, p, len);
|
|
}
|
|
|
|
static const unsigned char b64[] =
|
|
"./0123456789ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz";
|
|
|
|
static char *to64(char *s, unsigned int u, int n)
|
|
{
|
|
while (--n >= 0) {
|
|
*s++ = b64[u % 64];
|
|
u /= 64;
|
|
}
|
|
return s;
|
|
}
|
|
|
|
/* key limit is not part of the original design, added for DoS protection.
|
|
* rounds limit has been lowered (versus the reference/spec), also for DoS
|
|
* protection. runtime is O(klen^2 + klen*rounds) */
|
|
#define KEY_MAX 256
|
|
#define SALT_MAX 16
|
|
#define ROUNDS_DEFAULT 5000
|
|
#define ROUNDS_MIN 1000
|
|
#define ROUNDS_MAX 9999999
|
|
|
|
/* hash n bytes of the repeated md message digest */
|
|
static void hashmd(struct sha256 *s, unsigned int n, const void *md)
|
|
{
|
|
unsigned int i;
|
|
|
|
for (i = n; i > 32; i -= 32)
|
|
sha256_update(s, md, 32);
|
|
sha256_update(s, md, i);
|
|
}
|
|
|
|
static char *sha256crypt(const char *key, const char *setting, char *output)
|
|
{
|
|
struct sha256 ctx;
|
|
unsigned char md[32], kmd[32], smd[32];
|
|
unsigned int i, r, klen, slen;
|
|
char rounds[20] = "";
|
|
const char *salt;
|
|
char *p;
|
|
|
|
/* reject large keys */
|
|
klen = strnlen(key, KEY_MAX+1);
|
|
if (klen > KEY_MAX)
|
|
return 0;
|
|
|
|
/* setting: $5$rounds=n$salt$ (rounds=n$ and closing $ are optional) */
|
|
if (strncmp(setting, "$5$", 3) != 0)
|
|
return 0;
|
|
salt = setting + 3;
|
|
|
|
r = ROUNDS_DEFAULT;
|
|
if (strncmp(salt, "rounds=", sizeof "rounds=" - 1) == 0) {
|
|
unsigned long u;
|
|
char *end;
|
|
|
|
/*
|
|
* this is a deviation from the reference:
|
|
* bad rounds setting is rejected if it is
|
|
* - empty
|
|
* - unterminated (missing '$')
|
|
* - begins with anything but a decimal digit
|
|
* the reference implementation treats these bad
|
|
* rounds as part of the salt or parse them with
|
|
* strtoul semantics which may cause problems
|
|
* including non-portable hashes that depend on
|
|
* the host's value of ULONG_MAX.
|
|
*/
|
|
salt += sizeof "rounds=" - 1;
|
|
if (!isdigit(*salt))
|
|
return 0;
|
|
u = strtoul(salt, &end, 10);
|
|
if (*end != '$')
|
|
return 0;
|
|
salt = end+1;
|
|
if (u < ROUNDS_MIN)
|
|
r = ROUNDS_MIN;
|
|
else if (u > ROUNDS_MAX)
|
|
return 0;
|
|
else
|
|
r = u;
|
|
/* needed when rounds is zero prefixed or out of bounds */
|
|
(sprintf)(rounds, "rounds=%u$", r);
|
|
}
|
|
|
|
for (i = 0; i < SALT_MAX && salt[i] && salt[i] != '$'; i++)
|
|
/* reject characters that interfere with /etc/shadow parsing */
|
|
if (salt[i] == '\n' || salt[i] == ':')
|
|
return 0;
|
|
slen = i;
|
|
|
|
/* B = sha(key salt key) */
|
|
sha256_init(&ctx);
|
|
sha256_update(&ctx, key, klen);
|
|
sha256_update(&ctx, salt, slen);
|
|
sha256_update(&ctx, key, klen);
|
|
sha256_sum(&ctx, md);
|
|
|
|
/* A = sha(key salt repeat-B alternate-B-key) */
|
|
sha256_init(&ctx);
|
|
sha256_update(&ctx, key, klen);
|
|
sha256_update(&ctx, salt, slen);
|
|
hashmd(&ctx, klen, md);
|
|
for (i = klen; i > 0; i >>= 1)
|
|
if (i & 1)
|
|
sha256_update(&ctx, md, sizeof md);
|
|
else
|
|
sha256_update(&ctx, key, klen);
|
|
sha256_sum(&ctx, md);
|
|
|
|
/* DP = sha(repeat-key), this step takes O(klen^2) time */
|
|
sha256_init(&ctx);
|
|
for (i = 0; i < klen; i++)
|
|
sha256_update(&ctx, key, klen);
|
|
sha256_sum(&ctx, kmd);
|
|
|
|
/* DS = sha(repeat-salt) */
|
|
sha256_init(&ctx);
|
|
for (i = 0; i < 16 + md[0]; i++)
|
|
sha256_update(&ctx, salt, slen);
|
|
sha256_sum(&ctx, smd);
|
|
|
|
/* iterate A = f(A,DP,DS), this step takes O(rounds*klen) time */
|
|
for (i = 0; i < r; i++) {
|
|
sha256_init(&ctx);
|
|
if (i % 2)
|
|
hashmd(&ctx, klen, kmd);
|
|
else
|
|
sha256_update(&ctx, md, sizeof md);
|
|
if (i % 3)
|
|
sha256_update(&ctx, smd, slen);
|
|
if (i % 7)
|
|
hashmd(&ctx, klen, kmd);
|
|
if (i % 2)
|
|
sha256_update(&ctx, md, sizeof md);
|
|
else
|
|
hashmd(&ctx, klen, kmd);
|
|
sha256_sum(&ctx, md);
|
|
}
|
|
|
|
/* output is $5$rounds=n$salt$hash */
|
|
p = output;
|
|
p += (sprintf)(p, "$5$%s%.*s$", rounds, slen, salt);
|
|
static const unsigned char perm[][3] = {
|
|
0,10,20,21,1,11,12,22,2,3,13,23,24,4,14,
|
|
15,25,5,6,16,26,27,7,17,18,28,8,9,19,29 };
|
|
for (i=0; i<10; i++) p = to64(p,
|
|
(md[perm[i][0]]<<16)|(md[perm[i][1]]<<8)|md[perm[i][2]], 4);
|
|
p = to64(p, (md[31]<<8)|md[30], 3);
|
|
*p = 0;
|
|
return output;
|
|
}
|
|
|
|
char *__crypt_sha256(const char *key, const char *setting, char *output)
|
|
{
|
|
static const char testkey[] = "Xy01@#\x01\x02\x80\x7f\xff\r\n\x81\t !";
|
|
static const char testsetting[] = "$5$rounds=1234$abc0123456789$";
|
|
static const char testhash[] = "$5$rounds=1234$abc0123456789$3VfDjPt05VHFn47C/ojFZ6KRPYrOjj1lLbH.dkF3bZ6";
|
|
char testbuf[128];
|
|
char *p, *q;
|
|
|
|
p = sha256crypt(key, setting, output);
|
|
/* self test and stack cleanup */
|
|
q = sha256crypt(testkey, testsetting, testbuf);
|
|
if (!p || q != testbuf || memcmp(testbuf, testhash, sizeof testhash))
|
|
return "*";
|
|
return p;
|
|
}
|