Add a "fork" of musl as //fusl.

fusl/src/crypt/crypt_sha512.c

+/*
+ * public domain sha512 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 $6$ prefix is mandatory, '\n' and ':' is rejected
+ * in the salt and rounds= setting must contain a valid iteration count,
+ * on error "*" is returned.
+ */
+#include <ctype.h>
+#include <stdlib.h>
+#include <stdio.h>
+#include <string.h>
+#include <stdint.h>
+
+/* public domain sha512 implementation based on fips180-3 */
+/* >=2^64 bits messages are not supported (about 2000 peta bytes) */
+
+struct sha512 {
+        uint64_t len;     /* processed message length */
+        uint64_t h[8];    /* hash state */
+        uint8_t buf[128]; /* message block buffer */
+};
+
+static uint64_t ror(uint64_t n, int k) { return (n >> k) | (n << (64-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,28) ^ ror(x,34) ^ ror(x,39))
+#define S1(x)      (ror(x,14) ^ ror(x,18) ^ ror(x,41))
+#define R0(x)      (ror(x,1) ^ ror(x,8) ^ (x>>7))
+#define R1(x)      (ror(x,19) ^ ror(x,61) ^ (x>>6))
+
+static const uint64_t K[80] = {
+0x428a2f98d728ae22ULL, 0x7137449123ef65cdULL, 0xb5c0fbcfec4d3b2fULL, 0xe9b5dba58189dbbcULL,
+0x3956c25bf348b538ULL, 0x59f111f1b605d019ULL, 0x923f82a4af194f9bULL, 0xab1c5ed5da6d8118ULL,
+0xd807aa98a3030242ULL, 0x12835b0145706fbeULL, 0x243185be4ee4b28cULL, 0x550c7dc3d5ffb4e2ULL,
+0x72be5d74f27b896fULL, 0x80deb1fe3b1696b1ULL, 0x9bdc06a725c71235ULL, 0xc19bf174cf692694ULL,
+0xe49b69c19ef14ad2ULL, 0xefbe4786384f25e3ULL, 0x0fc19dc68b8cd5b5ULL, 0x240ca1cc77ac9c65ULL,
+0x2de92c6f592b0275ULL, 0x4a7484aa6ea6e483ULL, 0x5cb0a9dcbd41fbd4ULL, 0x76f988da831153b5ULL,
+0x983e5152ee66dfabULL, 0xa831c66d2db43210ULL, 0xb00327c898fb213fULL, 0xbf597fc7beef0ee4ULL,
+0xc6e00bf33da88fc2ULL, 0xd5a79147930aa725ULL, 0x06ca6351e003826fULL, 0x142929670a0e6e70ULL,
+0x27b70a8546d22ffcULL, 0x2e1b21385c26c926ULL, 0x4d2c6dfc5ac42aedULL, 0x53380d139d95b3dfULL,
+0x650a73548baf63deULL, 0x766a0abb3c77b2a8ULL, 0x81c2c92e47edaee6ULL, 0x92722c851482353bULL,
+0xa2bfe8a14cf10364ULL, 0xa81a664bbc423001ULL, 0xc24b8b70d0f89791ULL, 0xc76c51a30654be30ULL,
+0xd192e819d6ef5218ULL, 0xd69906245565a910ULL, 0xf40e35855771202aULL, 0x106aa07032bbd1b8ULL,
+0x19a4c116b8d2d0c8ULL, 0x1e376c085141ab53ULL, 0x2748774cdf8eeb99ULL, 0x34b0bcb5e19b48a8ULL,
+0x391c0cb3c5c95a63ULL, 0x4ed8aa4ae3418acbULL, 0x5b9cca4f7763e373ULL, 0x682e6ff3d6b2b8a3ULL,
+0x748f82ee5defb2fcULL, 0x78a5636f43172f60ULL, 0x84c87814a1f0ab72ULL, 0x8cc702081a6439ecULL,
+0x90befffa23631e28ULL, 0xa4506cebde82bde9ULL, 0xbef9a3f7b2c67915ULL, 0xc67178f2e372532bULL,
+0xca273eceea26619cULL, 0xd186b8c721c0c207ULL, 0xeada7dd6cde0eb1eULL, 0xf57d4f7fee6ed178ULL,
+0x06f067aa72176fbaULL, 0x0a637dc5a2c898a6ULL, 0x113f9804bef90daeULL, 0x1b710b35131c471bULL,
+0x28db77f523047d84ULL, 0x32caab7b40c72493ULL, 0x3c9ebe0a15c9bebcULL, 0x431d67c49c100d4cULL,
+0x4cc5d4becb3e42b6ULL, 0x597f299cfc657e2aULL, 0x5fcb6fab3ad6faecULL, 0x6c44198c4a475817ULL
+};
+
+static void processblock(struct sha512 *s, const uint8_t *buf)
+{
+        uint64_t W[80], t1, t2, a, b, c, d, e, f, g, h;
+        int i;
+
+        for (i = 0; i < 16; i++) {
+                W[i] = (uint64_t)buf[8*i]<<56;
+                W[i] |= (uint64_t)buf[8*i+1]<<48;
+                W[i] |= (uint64_t)buf[8*i+2]<<40;
+                W[i] |= (uint64_t)buf[8*i+3]<<32;
+                W[i] |= (uint64_t)buf[8*i+4]<<24;
+                W[i] |= (uint64_t)buf[8*i+5]<<16;
+                W[i] |= (uint64_t)buf[8*i+6]<<8;
+                W[i] |= buf[8*i+7];
+        }
+        for (; i < 80; 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 < 80; i++) {
+                t1 = h + S1(e) + Ch(e,f,g) + K[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 sha512 *s)
+{
+        unsigned r = s->len % 128;
+
+        s->buf[r++] = 0x80;
+        if (r > 112) {
+                memset(s->buf + r, 0, 128 - r);
+                r = 0;
+                processblock(s, s->buf);
+        }
+        memset(s->buf + r, 0, 120 - r);
+        s->len *= 8;
+        s->buf[120] = s->len >> 56;
+        s->buf[121] = s->len >> 48;
+        s->buf[122] = s->len >> 40;
+        s->buf[123] = s->len >> 32;
+        s->buf[124] = s->len >> 24;
+        s->buf[125] = s->len >> 16;
+        s->buf[126] = s->len >> 8;
+        s->buf[127] = s->len;
+        processblock(s, s->buf);
+}
+
+static void sha512_init(struct sha512 *s)
+{
+        s->len = 0;
+        s->h[0] = 0x6a09e667f3bcc908ULL;
+        s->h[1] = 0xbb67ae8584caa73bULL;
+        s->h[2] = 0x3c6ef372fe94f82bULL;
+        s->h[3] = 0xa54ff53a5f1d36f1ULL;
+        s->h[4] = 0x510e527fade682d1ULL;
+        s->h[5] = 0x9b05688c2b3e6c1fULL;
+        s->h[6] = 0x1f83d9abfb41bd6bULL;
+        s->h[7] = 0x5be0cd19137e2179ULL;
+}
+
+static void sha512_sum(struct sha512 *s, uint8_t *md)
+{
+        int i;
+
+        pad(s);
+        for (i = 0; i < 8; i++) {
+                md[8*i] = s->h[i] >> 56;
+                md[8*i+1] = s->h[i] >> 48;
+                md[8*i+2] = s->h[i] >> 40;
+                md[8*i+3] = s->h[i] >> 32;
+                md[8*i+4] = s->h[i] >> 24;
+                md[8*i+5] = s->h[i] >> 16;
+                md[8*i+6] = s->h[i] >> 8;
+                md[8*i+7] = s->h[i];
+        }
+}
+
+static void sha512_update(struct sha512 *s, const void *m, unsigned long len)
+{
+        const uint8_t *p = m;
+        unsigned r = s->len % 128;
+
+        s->len += len;
+        if (r) {
+                if (len < 128 - r) {
+                        memcpy(s->buf + r, p, len);
+                        return;
+                }
+                memcpy(s->buf + r, p, 128 - r);
+                len -= 128 - r;
+                p += 128 - r;
+                processblock(s, s->buf);
+        }
+        for (; len >= 128; len -= 128, p += 128)
+                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 sha512 *s, unsigned int n, const void *md)
+{
+        unsigned int i;
+
+        for (i = n; i > 64; i -= 64)
+                sha512_update(s, md, 64);
+        sha512_update(s, md, i);
+}
+
+static char *sha512crypt(const char *key, const char *setting, char *output)
+{
+        struct sha512 ctx;
+        unsigned char md[64], kmd[64], smd[64];
+        unsigned int i, r, klen, slen;
+        char rounds[20] = "";
+        const char *salt;
+        char *p;
+
+        /* reject large keys */
+        for (i = 0; i <= KEY_MAX && key[i]; i++);
+        if (i > KEY_MAX)
+                return 0;
+        klen = i;
+
+        /* setting: $6$rounds=n$salt$ (rounds=n$ and closing $ are optional) */
+        if (strncmp(setting, "$6$", 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)
+                        r = ROUNDS_MAX;
+                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) */
+        sha512_init(&ctx);
+        sha512_update(&ctx, key, klen);
+        sha512_update(&ctx, salt, slen);
+        sha512_update(&ctx, key, klen);
+        sha512_sum(&ctx, md);
+
+        /* A = sha(key salt repeat-B alternate-B-key) */
+        sha512_init(&ctx);
+        sha512_update(&ctx, key, klen);
+        sha512_update(&ctx, salt, slen);
+        hashmd(&ctx, klen, md);
+        for (i = klen; i > 0; i >>= 1)
+                if (i & 1)
+                        sha512_update(&ctx, md, sizeof md);
+                else
+                        sha512_update(&ctx, key, klen);
+        sha512_sum(&ctx, md);
+
+        /* DP = sha(repeat-key), this step takes O(klen^2) time */
+        sha512_init(&ctx);
+        for (i = 0; i < klen; i++)
+                sha512_update(&ctx, key, klen);
+        sha512_sum(&ctx, kmd);
+
+        /* DS = sha(repeat-salt) */
+        sha512_init(&ctx);
+        for (i = 0; i < 16 + md[0]; i++)
+                sha512_update(&ctx, salt, slen);
+        sha512_sum(&ctx, smd);
+
+        /* iterate A = f(A,DP,DS), this step takes O(rounds*klen) time */
+        for (i = 0; i < r; i++) {
+                sha512_init(&ctx);
+                if (i % 2)
+                        hashmd(&ctx, klen, kmd);
+                else
+                        sha512_update(&ctx, md, sizeof md);
+                if (i % 3)
+                        sha512_update(&ctx, smd, slen);
+                if (i % 7)
+                        hashmd(&ctx, klen, kmd);
+                if (i % 2)
+                        sha512_update(&ctx, md, sizeof md);
+                else
+                        hashmd(&ctx, klen, kmd);
+                sha512_sum(&ctx, md);
+        }
+
+        /* output is $6$rounds=n$salt$hash */
+        p = output;
+        p += sprintf(p, "$6$%s%.*s$", rounds, slen, salt);
+#if 1
+        static const unsigned char perm[][3] = {
+                0,21,42,22,43,1,44,2,23,3,24,45,25,46,4,
+                47,5,26,6,27,48,28,49,7,50,8,29,9,30,51,
+                31,52,10,53,11,32,12,33,54,34,55,13,56,14,35,
+                15,36,57,37,58,16,59,17,38,18,39,60,40,61,19,
+                62,20,41 };
+        for (i=0; i<21; i++) p = to64(p,
+                (md[perm[i][0]]<<16)|(md[perm[i][1]]<<8)|md[perm[i][2]], 4);
+#else
+        p = to64(p, (md[0]<<16)|(md[21]<<8)|md[42], 4);
+        p = to64(p, (md[22]<<16)|(md[43]<<8)|md[1], 4);
+        p = to64(p, (md[44]<<16)|(md[2]<<8)|md[23], 4);
+        p = to64(p, (md[3]<<16)|(md[24]<<8)|md[45], 4);
+        p = to64(p, (md[25]<<16)|(md[46]<<8)|md[4], 4);
+        p = to64(p, (md[47]<<16)|(md[5]<<8)|md[26], 4);
+        p = to64(p, (md[6]<<16)|(md[27]<<8)|md[48], 4);
+        p = to64(p, (md[28]<<16)|(md[49]<<8)|md[7], 4);
+        p = to64(p, (md[50]<<16)|(md[8]<<8)|md[29], 4);
+        p = to64(p, (md[9]<<16)|(md[30]<<8)|md[51], 4);
+        p = to64(p, (md[31]<<16)|(md[52]<<8)|md[10], 4);
+        p = to64(p, (md[53]<<16)|(md[11]<<8)|md[32], 4);
+        p = to64(p, (md[12]<<16)|(md[33]<<8)|md[54], 4);
+        p = to64(p, (md[34]<<16)|(md[55]<<8)|md[13], 4);
+        p = to64(p, (md[56]<<16)|(md[14]<<8)|md[35], 4);
+        p = to64(p, (md[15]<<16)|(md[36]<<8)|md[57], 4);
+        p = to64(p, (md[37]<<16)|(md[58]<<8)|md[16], 4);
+        p = to64(p, (md[59]<<16)|(md[17]<<8)|md[38], 4);
+        p = to64(p, (md[18]<<16)|(md[39]<<8)|md[60], 4);
+        p = to64(p, (md[40]<<16)|(md[61]<<8)|md[19], 4);
+        p = to64(p, (md[62]<<16)|(md[20]<<8)|md[41], 4);
+#endif
+        p = to64(p, md[63], 2);
+        *p = 0;
+        return output;
+}
+
+char *__crypt_sha512(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[] = "$6$rounds=1234$abc0123456789$";
+        static const char testhash[] = "$6$rounds=1234$abc0123456789$BCpt8zLrc/RcyuXmCDOE1ALqMXB2MH6n1g891HhFj8.w7LxGv.FTkqq6Vxc/km3Y0jE0j24jY5PIv/oOu6reg1";
+        char testbuf[128];
+        char *p, *q;
+
+        p = sha512crypt(key, setting, output);
+        /* self test and stack cleanup */
+        q = sha512crypt(testkey, testsetting, testbuf);
+        if (!p || q != testbuf || memcmp(testbuf, testhash, sizeof testhash))
+                return "*";
+        return p;
+}