DKIM: fix $dkim_key_length in verify
[exim.git] / src / src / pdkim / pdkim.h
index 3c420ae63288b2b03bf884e1287167abf3e8d1f8..0b21df8ab358ea5b12e1f0128cf7d828408a35d0 100644 (file)
@@ -2,7 +2,7 @@
  *  PDKIM - a RFC4871 (DKIM) implementation
  *
  *  Copyright (C) 2009 - 2012  Tom Kistner <tom@duncanthrax.net>
- *  Copyright (c) 2016 - 2017  Jeremy Harris
+ *  Copyright (c) 2016 - 2018  Jeremy Harris
  *
  *  http://duncanthrax.net/pdkim/
  *
 #include "../blob.h"
 #include "../hash.h"
 
+#define PDKIM_DEFAULT_SIGN_HEADERS "From:Sender:Reply-To:Subject:Date:"\
+                             "Message-ID:To:Cc:MIME-Version:Content-Type:"\
+                             "Content-Transfer-Encoding:Content-ID:"\
+                             "Content-Description:Resent-Date:Resent-From:"\
+                             "Resent-Sender:Resent-To:Resent-Cc:"\
+                             "Resent-Message-ID:In-Reply-To:References:"\
+                             "List-Id:List-Help:List-Unsubscribe:"\
+                             "List-Subscribe:List-Post:List-Owner:List-Archive"
+
+#define PDKIM_OVERSIGN_HEADERS "+From:+Sender:+Reply-To:+Subject:+Date:"\
+                             "+Message-ID:+To:+Cc:+MIME-Version:+Content-Type:"\
+                             "+Content-Transfer-Encoding:+Content-ID:"\
+                             "+Content-Description:+Resent-Date:+Resent-From:"\
+                             "+Resent-Sender:+Resent-To:+Resent-Cc:"\
+                             "+Resent-Message-ID:+In-Reply-To:+References:"\
+                             "+List-Id:+List-Help:+List-Unsubscribe:"\
+                             "+List-Subscribe:+List-Post:+List-Owner:+List-Archive"
+
 /* -------------------------------------------------------------------------- */
 /* Length of the preallocated buffer for the "answer" from the dns/txt
    callback function. This should match the maximum RDLENGTH from DNS. */
@@ -39,8 +57,9 @@
 #define PDKIM_ERR_RSA_SIGNING      -102
 #define PDKIM_ERR_LONG_LINE        -103
 #define PDKIM_ERR_BUFFER_TOO_SMALL -104
-#define PDKIM_SIGN_PRIVKEY_WRAP    -105
-#define PDKIM_SIGN_PRIVKEY_B64D    -106
+#define PDKIM_ERR_EXCESS_SIGS     -105
+#define PDKIM_SIGN_PRIVKEY_WRAP    -106
+#define PDKIM_SIGN_PRIVKEY_B64D    -107
 
 /* -------------------------------------------------------------------------- */
 /* Main/Extended verification status */
@@ -48,6 +67,7 @@
 #define PDKIM_VERIFY_INVALID   1
 #define PDKIM_VERIFY_FAIL      2
 #define PDKIM_VERIFY_PASS      3
+#define PDKIM_VERIFY_POLICY    BIT(31)
 
 #define PDKIM_VERIFY_FAIL_BODY                    1
 #define PDKIM_VERIFY_FAIL_MESSAGE                 2
 #define PDKIM_CANON_SIMPLE        0
 #define PDKIM_CANON_RELAXED       1
 
-/*XXX change to enums */
-#define PDKIM_HASH_SHA256         1
-
-#define PDKIM_KEYTYPE_RSA         0
-
 /* -------------------------------------------------------------------------- */
 /* Some required forward declarations, please ignore */
 typedef struct pdkim_stringlist pdkim_stringlist;
@@ -99,10 +114,8 @@ typedef struct pdkim_pubkey {
   const uschar *granularity;      /* g=  */
 
   const uschar * hashes;          /* h=  */
-#ifdef notdef
-  uschar *keytype;                /* k=  */
-#endif
-  const uschar *srvtype;          /* s=  */
+  const uschar * keytype;         /* k=  */
+  const uschar * srvtype;         /* s=  */
   uschar *notes;                  /* n=  */
 
   blob  key;                      /* p=  */
@@ -110,17 +123,35 @@ typedef struct pdkim_pubkey {
   int   no_subdomaining;          /* t=s */
 } pdkim_pubkey;
 
+/* -------------------------------------------------------------------------- */
+/* Body-hash to be calculated */
+typedef struct pdkim_bodyhash {
+  struct pdkim_bodyhash *      next;
+  int                          hashtype;
+  int                          canon_method;
+  long                         bodylength;
+
+  hctx                                 body_hash_ctx;
+  unsigned long                        signed_body_bytes;      /* done so far */
+  int                          num_buffered_blanklines;
+
+  blob                         bh;                     /* completed hash */
+} pdkim_bodyhash;
+
 /* -------------------------------------------------------------------------- */
 /* Signature as it appears in a DKIM-Signature header */
 typedef struct pdkim_signature {
+  struct pdkim_signature * next;
 
   /* Bits stored in a DKIM signature header --------------------------- */
 
   /* (v=) The version, as an integer. Currently, always "1" */
   int version;
 
-  int keytype; /* PDKIM_KEYTYPE_RSA */
-  int hashtype;        /* pdkim_hashes index */
+  /* (a=) The signature algorithm. */
+  int          keytype;        /* pdkim_keytypes index */
+  unsigned     keybits;        /* size of the key */
+  int          hashtype;       /* pdkim_hashes index */
 
   /* (c=x/) Header canonicalization method. Either PDKIM_CANON_SIMPLE
      or PDKIM_CANON_RELAXED */
@@ -166,7 +197,7 @@ typedef struct pdkim_signature {
   /* (bh=) Raw body hash data, along with its length in bytes */
   blob bodyhash;
 
-  /* Folded DKIM-Signature: header. Singing only, NULL for verifying.
+  /* Folded DKIM-Signature: header. Signing only, NULL for verifying.
      Ready for insertion into the message. Note: Folded using CRLFTB,
      but final line terminator is NOT included. Note2: This buffer is
      free()d when you call pdkim_free_ctx(). */
@@ -223,17 +254,13 @@ typedef struct pdkim_signature {
      Caution: is NULL if signing or if no record was retrieved. */
   pdkim_pubkey *pubkey;
 
-  /* Pointer to the next pdkim_signature signature. NULL if signing or if
-     this is the last signature. */
-  void *next;
-
   /* Properties below this point are used internally only ------------- */
 
   /* Per-signature helper variables ----------------------------------- */
-  hctx         body_hash_ctx;
+  pdkim_bodyhash *calc_body_hash;      /* hash to be / being calculated */
+
+  pdkim_stringlist *headers;           /* Raw headers included in the sig */
 
-  unsigned long signed_body_bytes; /* How many body bytes we hashed     */
-  pdkim_stringlist *headers; /* Raw headers included in the sig         */
   /* Signing specific ------------------------------------------------- */
   uschar * privkey;         /* Private key                                 */
   uschar * sign_headers;    /* To-be-signed header names                   */
@@ -256,21 +283,32 @@ typedef struct pdkim_ctx {
   /* One (signing) or several chained (verification) signatures */
   pdkim_signature *sig;
 
+  /* One (signing) or several chained (verification) bodyhashes */
+  pdkim_bodyhash *bodyhash;
+
   /* Callback for dns/txt query method (verification only) */
-  int(*dns_txt_callback)(char *, char *);
+  uschar * (*dns_txt_callback)(const uschar *);
 
   /* Coder's little helpers */
-  uschar    *cur_header;
-  int        cur_header_size;
-  int        cur_header_len;
-  char      *linebuf;
+  gstring   *cur_header;
+  uschar    *linebuf;
   int        linebuf_offset;
-  int        num_buffered_crlf;
   int        num_headers;
   pdkim_stringlist *headers; /* Raw headers for verification         */
 } pdkim_ctx;
 
 
+/******************************************************************************/
+
+typedef struct {
+  const uschar * dkim_hashname;
+  hashmethod    exim_hashmethod;
+} pdkim_hashtype;
+extern const pdkim_hashtype pdkim_hashes[];
+
+/******************************************************************************/
+
+
 /* -------------------------------------------------------------------------- */
 /* API functions. Please see the sample code in sample/test_sign.c and
    sample/test_verify.c for documentation.
@@ -282,19 +320,27 @@ extern "C" {
 
 void      pdkim_init         (void);
 
+void      pdkim_init_context (pdkim_ctx *, BOOL, uschar * (*)(const uschar *));
+
 DLLEXPORT
-pdkim_ctx *pdkim_init_sign    (uschar *, uschar *, uschar *, uschar *,
-                             BOOL, int(*)(char *, char *), const uschar **);
+pdkim_signature *pdkim_init_sign    (pdkim_ctx *,
+                              uschar *, uschar *, uschar *, uschar *,
+                              const uschar **);
 
 DLLEXPORT
-pdkim_ctx *pdkim_init_verify  (int(*)(char *, char *), BOOL);
+pdkim_ctx *pdkim_init_verify  (uschar * (*)(const uschar *), BOOL);
 
 DLLEXPORT
-int        pdkim_set_optional (pdkim_ctx *, char *, char *,int, int,
+void       pdkim_set_optional (pdkim_signature *, char *, char *,int, int,
                                long,
                                unsigned long,
                                unsigned long);
 
+int            pdkim_hashname_to_hashtype(const uschar *, unsigned);
+void           pdkim_cstring_to_canons(const uschar *, unsigned, int *, int *);
+pdkim_bodyhash *pdkim_set_bodyhash(pdkim_ctx *, int, int, long);
+pdkim_bodyhash *pdkim_set_sig_bodyhash(pdkim_ctx *, pdkim_signature *);
+
 DLLEXPORT
 int        pdkim_feed         (pdkim_ctx *, uschar *, int);
 DLLEXPORT
@@ -306,7 +352,14 @@ void       pdkim_free_ctx     (pdkim_ctx *);
 
 const uschar * pdkim_errstr(int);
 
-uschar *       dkim_sig_to_a_tag(pdkim_signature * sig);
+extern uschar *                pdkim_encode_base64(blob *);
+extern void            pdkim_decode_base64(const uschar *, blob *);
+extern void            pdkim_hexprint(const uschar *, int);
+extern void            pdkim_quoteprint(const uschar *, int);
+extern pdkim_pubkey *  pdkim_parse_pubkey_record(const uschar *);
+extern uschar *                pdkim_relax_header_n(const uschar *, int, BOOL);
+extern uschar *                pdkim_relax_header(const uschar *, BOOL);
+extern uschar *                dkim_sig_to_a_tag(const pdkim_signature *);
 
 #ifdef __cplusplus
 }