+
+ err:
+ OPENSSL_free(ascii_passwd);
+ EVP_MD_CTX_free(md2);
+ EVP_MD_CTX_free(md);
+ return NULL;
+}
+
+/*
+ * SHA based password algorithm, describe by Ulrich Drepper here:
+ * https://www.akkadia.org/drepper/SHA-crypt.txt
+ * (note that it's in the public domain)
+ */
+static char *shacrypt(const char *passwd, const char *magic, const char *salt)
+{
+ /* Prefix for optional rounds specification. */
+ static const char rounds_prefix[] = "rounds=";
+ /* Maximum salt string length. */
+# define SALT_LEN_MAX 16
+ /* Default number of rounds if not explicitly specified. */
+# define ROUNDS_DEFAULT 5000
+ /* Minimum number of rounds. */
+# define ROUNDS_MIN 1000
+ /* Maximum number of rounds. */
+# define ROUNDS_MAX 999999999
+
+ /* "$6$rounds=<N>$......salt......$...shahash(up to 86 chars)...\0" */
+ static char out_buf[3 + 17 + 17 + 86 + 1];
+ unsigned char buf[SHA512_DIGEST_LENGTH];
+ unsigned char temp_buf[SHA512_DIGEST_LENGTH];
+ size_t buf_size = 0;
+ char ascii_magic[2];
+ char ascii_salt[17]; /* Max 16 chars plus '\0' */
+ char *ascii_passwd = NULL;
+ size_t n;
+ EVP_MD_CTX *md = NULL, *md2 = NULL;
+ const EVP_MD *sha = NULL;
+ size_t passwd_len, salt_len, magic_len;
+ unsigned int rounds = 5000; /* Default */
+ char rounds_custom = 0;
+ char *p_bytes = NULL;
+ char *s_bytes = NULL;
+ char *cp = NULL;
+
+ passwd_len = strlen(passwd);
+ magic_len = strlen(magic);
+
+ /* assert it's "5" or "6" */
+ if (magic_len != 1)
+ return NULL;
+
+ switch (magic[0]) {
+ case '5':
+ sha = EVP_sha256();
+ buf_size = 32;
+ break;
+ case '6':
+ sha = EVP_sha512();
+ buf_size = 64;
+ break;
+ default:
+ return NULL;
+ }
+
+ if (strncmp(salt, rounds_prefix, sizeof(rounds_prefix) - 1) == 0) {
+ const char *num = salt + sizeof(rounds_prefix) - 1;
+ char *endp;
+ unsigned long int srounds = strtoul (num, &endp, 10);
+ if (*endp == '$') {
+ salt = endp + 1;
+ if (srounds > ROUNDS_MAX)
+ rounds = ROUNDS_MAX;
+ else if (srounds < ROUNDS_MIN)
+ rounds = ROUNDS_MIN;
+ else
+ rounds = (unsigned int)srounds;
+ rounds_custom = 1;
+ } else {
+ return NULL;
+ }
+ }
+
+ OPENSSL_strlcpy(ascii_magic, magic, sizeof(ascii_magic));
+#ifdef CHARSET_EBCDIC
+ if ((magic[0] & 0x80) != 0) /* High bit is 1 in EBCDIC alnums */
+ ebcdic2ascii(ascii_magic, ascii_magic, magic_len);
+#endif
+
+ /* The salt gets truncated to 16 chars */
+ OPENSSL_strlcpy(ascii_salt, salt, sizeof(ascii_salt));
+ salt_len = strlen(ascii_salt);
+#ifdef CHARSET_EBCDIC
+ ebcdic2ascii(ascii_salt, ascii_salt, salt_len);
+#endif
+
+#ifdef CHARSET_EBCDIC
+ ascii_passwd = OPENSSL_strdup(passwd);
+ if (ascii_passwd == NULL)
+ return NULL;
+ ebcdic2ascii(ascii_passwd, ascii_passwd, passwd_len);
+ passwd = ascii_passwd;
+#endif
+
+ out_buf[0] = 0;
+ OPENSSL_strlcat(out_buf, ascii_dollar, sizeof(out_buf));
+ OPENSSL_strlcat(out_buf, ascii_magic, sizeof(out_buf));
+ OPENSSL_strlcat(out_buf, ascii_dollar, sizeof(out_buf));
+ if (rounds_custom) {
+ char tmp_buf[80]; /* "rounds=999999999" */
+ sprintf(tmp_buf, "rounds=%u", rounds);
+#ifdef CHARSET_EBCDIC
+ /* In case we're really on a ASCII based platform and just pretend */
+ if (tmp_buf[0] != 0x72) /* ASCII 'r' */
+ ebcdic2ascii(tmp_buf, tmp_buf, strlen(tmp_buf));
+#endif
+ OPENSSL_strlcat(out_buf, tmp_buf, sizeof(out_buf));
+ OPENSSL_strlcat(out_buf, ascii_dollar, sizeof(out_buf));
+ }
+ OPENSSL_strlcat(out_buf, ascii_salt, sizeof(out_buf));
+
+ /* assert "$5$rounds=999999999$......salt......" */
+ if (strlen(out_buf) > 3 + 17 * rounds_custom + salt_len )
+ goto err;
+
+ md = EVP_MD_CTX_new();
+ if (md == NULL
+ || !EVP_DigestInit_ex(md, sha, NULL)
+ || !EVP_DigestUpdate(md, passwd, passwd_len)
+ || !EVP_DigestUpdate(md, ascii_salt, salt_len))
+ goto err;
+
+ md2 = EVP_MD_CTX_new();
+ if (md2 == NULL
+ || !EVP_DigestInit_ex(md2, sha, NULL)
+ || !EVP_DigestUpdate(md2, passwd, passwd_len)
+ || !EVP_DigestUpdate(md2, ascii_salt, salt_len)
+ || !EVP_DigestUpdate(md2, passwd, passwd_len)
+ || !EVP_DigestFinal_ex(md2, buf, NULL))
+ goto err;
+
+ for (n = passwd_len; n > buf_size; n -= buf_size) {
+ if (!EVP_DigestUpdate(md, buf, buf_size))
+ goto err;
+ }
+ if (!EVP_DigestUpdate(md, buf, n))
+ goto err;
+
+ n = passwd_len;
+ while (n) {
+ if (!EVP_DigestUpdate(md,
+ (n & 1) ? buf : (unsigned const char *)passwd,
+ (n & 1) ? buf_size : passwd_len))
+ goto err;
+ n >>= 1;
+ }
+ if (!EVP_DigestFinal_ex(md, buf, NULL))
+ return NULL;
+
+ /* P sequence */
+ if (!EVP_DigestInit_ex(md2, sha, NULL))
+ goto err;
+
+ for (n = passwd_len; n > 0; n--)
+ if (!EVP_DigestUpdate(md2, passwd, passwd_len))
+ goto err;
+
+ if (!EVP_DigestFinal_ex(md2, temp_buf, NULL))
+ return NULL;
+
+ if ((p_bytes = OPENSSL_zalloc(passwd_len)) == NULL)
+ goto err;
+ for (cp = p_bytes, n = passwd_len; n > buf_size; n -= buf_size, cp += buf_size)
+ memcpy(cp, temp_buf, buf_size);
+ memcpy(cp, temp_buf, n);
+
+ /* S sequence */
+ if (!EVP_DigestInit_ex(md2, sha, NULL))
+ goto err;
+
+ for (n = 16 + buf[0]; n > 0; n--)
+ if (!EVP_DigestUpdate(md2, ascii_salt, salt_len))
+ goto err;
+
+ if (!EVP_DigestFinal_ex(md2, temp_buf, NULL))
+ return NULL;
+
+ if ((s_bytes = OPENSSL_zalloc(salt_len)) == NULL)
+ goto err;
+ for (cp = s_bytes, n = salt_len; n > buf_size; n -= buf_size, cp += buf_size)
+ memcpy(cp, temp_buf, buf_size);
+ memcpy(cp, temp_buf, n);
+
+ for (n = 0; n < rounds; n++) {
+ if (!EVP_DigestInit_ex(md2, sha, NULL))
+ goto err;
+ if (!EVP_DigestUpdate(md2,
+ (n & 1) ? (unsigned const char *)p_bytes : buf,
+ (n & 1) ? passwd_len : buf_size))
+ goto err;
+ if (n % 3) {
+ if (!EVP_DigestUpdate(md2, s_bytes, salt_len))
+ goto err;
+ }
+ if (n % 7) {
+ if (!EVP_DigestUpdate(md2, p_bytes, passwd_len))
+ goto err;
+ }
+ if (!EVP_DigestUpdate(md2,
+ (n & 1) ? buf : (unsigned const char *)p_bytes,
+ (n & 1) ? buf_size : passwd_len))
+ goto err;
+ if (!EVP_DigestFinal_ex(md2, buf, NULL))
+ goto err;
+ }
+ EVP_MD_CTX_free(md2);
+ EVP_MD_CTX_free(md);
+ md2 = NULL;
+ md = NULL;
+ OPENSSL_free(p_bytes);
+ OPENSSL_free(s_bytes);
+ p_bytes = NULL;
+ s_bytes = NULL;
+
+ cp = out_buf + strlen(out_buf);
+ *cp++ = ascii_dollar[0];
+
+# define b64_from_24bit(B2, B1, B0, N) \
+ do { \
+ unsigned int w = ((B2) << 16) | ((B1) << 8) | (B0); \
+ int i = (N); \
+ while (i-- > 0) \
+ { \
+ *cp++ = cov_2char[w & 0x3f]; \
+ w >>= 6; \
+ } \
+ } while (0)
+
+ switch (magic[0]) {
+ case '5':
+ b64_from_24bit (buf[0], buf[10], buf[20], 4);
+ b64_from_24bit (buf[21], buf[1], buf[11], 4);
+ b64_from_24bit (buf[12], buf[22], buf[2], 4);
+ b64_from_24bit (buf[3], buf[13], buf[23], 4);
+ b64_from_24bit (buf[24], buf[4], buf[14], 4);
+ b64_from_24bit (buf[15], buf[25], buf[5], 4);
+ b64_from_24bit (buf[6], buf[16], buf[26], 4);
+ b64_from_24bit (buf[27], buf[7], buf[17], 4);
+ b64_from_24bit (buf[18], buf[28], buf[8], 4);
+ b64_from_24bit (buf[9], buf[19], buf[29], 4);
+ b64_from_24bit (0, buf[31], buf[30], 3);
+ break;
+ case '6':
+ b64_from_24bit (buf[0], buf[21], buf[42], 4);
+ b64_from_24bit (buf[22], buf[43], buf[1], 4);
+ b64_from_24bit (buf[44], buf[2], buf[23], 4);
+ b64_from_24bit (buf[3], buf[24], buf[45], 4);
+ b64_from_24bit (buf[25], buf[46], buf[4], 4);
+ b64_from_24bit (buf[47], buf[5], buf[26], 4);
+ b64_from_24bit (buf[6], buf[27], buf[48], 4);
+ b64_from_24bit (buf[28], buf[49], buf[7], 4);
+ b64_from_24bit (buf[50], buf[8], buf[29], 4);
+ b64_from_24bit (buf[9], buf[30], buf[51], 4);
+ b64_from_24bit (buf[31], buf[52], buf[10], 4);
+ b64_from_24bit (buf[53], buf[11], buf[32], 4);
+ b64_from_24bit (buf[12], buf[33], buf[54], 4);
+ b64_from_24bit (buf[34], buf[55], buf[13], 4);
+ b64_from_24bit (buf[56], buf[14], buf[35], 4);
+ b64_from_24bit (buf[15], buf[36], buf[57], 4);
+ b64_from_24bit (buf[37], buf[58], buf[16], 4);
+ b64_from_24bit (buf[59], buf[17], buf[38], 4);
+ b64_from_24bit (buf[18], buf[39], buf[60], 4);
+ b64_from_24bit (buf[40], buf[61], buf[19], 4);
+ b64_from_24bit (buf[62], buf[20], buf[41], 4);
+ b64_from_24bit (0, 0, buf[63], 2);
+ break;
+ default:
+ goto err;
+ }
+ *cp = '\0';
+#ifdef CHARSET_EBCDIC
+ ascii2ebcdic(out_buf, out_buf, strlen(out_buf));
+#endif
+
+ return out_buf;
+
+ err:
+ EVP_MD_CTX_free(md2);
+ EVP_MD_CTX_free(md);
+ OPENSSL_free(p_bytes);
+ OPENSSL_free(s_bytes);
+ OPENSSL_free(ascii_passwd);
+ return NULL;