Added support for SSHA256 password scheme.

--HG--
branch : HEAD

diff --git a/src/auth/password-scheme.c b/src/auth/password-scheme.c
index cb75f99f4ea641f28d4ec9705840d6b27dd161a5..46f17599a6596d3cb10fea70dcc64d52f6743fd5 100644 (file)
--- a/src/auth/password-scheme.c
+++ b/src/auth/password-scheme.c
@@ -401,6 +401,47 @@ static bool ssha_verify(const char *plaintext, const char *user,
        return memcmp(sha1_digest, raw_password, SHA1_RESULTLEN) == 0;
 }
 
+static void
+ssha256_generate(const char *plaintext, const char *user ATTR_UNUSED,
+                const unsigned char **raw_password_r, size_t *size_r)
+{
+#define SSHA256_SALT_LEN 4
+       unsigned char *digest, *salt;
+       struct sha256_ctx ctx;
+
+       digest = t_malloc(SHA256_RESULTLEN + SSHA256_SALT_LEN);
+       salt = digest + SHA256_RESULTLEN;
+       random_fill(salt, SSHA256_SALT_LEN);
+
+       sha256_init(&ctx);
+       sha256_loop(&ctx, plaintext, strlen(plaintext));
+       sha256_loop(&ctx, salt, SSHA256_SALT_LEN);
+       sha256_result(&ctx, digest);
+
+       *raw_password_r = digest;
+       *size_r = SHA256_RESULTLEN + SSHA256_SALT_LEN;
+}
+
+static bool ssha256_verify(const char *plaintext, const char *user,
+                          const unsigned char *raw_password, size_t size)
+{
+       unsigned char sha256_digest[SHA256_RESULTLEN];
+       struct sha256_ctx ctx;
+
+       /* format: <SHA256 hash><salt> */
+       if (size <= SHA256_RESULTLEN) {
+               i_error("ssha256_verify(%s): SSHA256 password too short", user);
+               return FALSE;
+       }
+
+       sha256_init(&ctx);
+       sha256_loop(&ctx, plaintext, strlen(plaintext));
+       sha256_loop(&ctx, raw_password + SHA256_RESULTLEN,
+                   size - SHA256_RESULTLEN);
+       sha256_result(&ctx, sha256_digest);
+       return memcmp(sha256_digest, raw_password, SHA256_RESULTLEN) == 0;
+}
+
 static void
 smd5_generate(const char *plaintext, const char *user ATTR_UNUSED,
              const unsigned char **raw_password_r, size_t *size_r)
@@ -596,6 +637,7 @@ static const struct password_scheme builtin_schemes[] = {
          NULL, sha256_generate },
        { "SMD5", PW_ENCODING_BASE64, 0, smd5_verify, smd5_generate },
        { "SSHA", PW_ENCODING_BASE64, 0, ssha_verify, ssha_generate },
+       { "SSHA256", PW_ENCODING_BASE64, 0, ssha256_verify, ssha256_generate },
        { "PLAIN", PW_ENCODING_NONE, 0, NULL, plain_generate },
        { "CLEARTEXT", PW_ENCODING_NONE, 0, NULL, plain_generate },
        { "CRAM-MD5", PW_ENCODING_HEX, 0, NULL, cram_md5_generate },