* Start dkim support implementation.

1 files changed, 180 insertions, 0 deletions

diff --git a/src/dkim.h b/src/dkim.h
new file mode 100644
index 000000000..a7ad514bf
--- /dev/null
+++ b/src/dkim.h
@@ -0,0 +1,180 @@
+/* Copyright (c) 2010-2011, Vsevolod Stakhov
+ * All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions are met:
+ *       * Redistributions of source code must retain the above copyright
+ *         notice, this list of conditions and the following disclaimer.
+ *       * Redistributions in binary form must reproduce the above copyright
+ *         notice, this list of conditions and the following disclaimer in the
+ *         documentation and/or other materials provided with the distribution.
+ *
+ * THIS SOFTWARE IS PROVIDED ''AS IS'' AND ANY
+ * EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
+ * WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
+ * DISCLAIMED. IN NO EVENT SHALL AUTHOR BE LIABLE FOR ANY
+ * DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
+ * (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
+ * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND
+ * ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+ * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
+ * SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ */
+
+
+#ifndef DKIM_H_
+#define DKIM_H_
+
+#include "config.h"
+#include "event.h"
+#include "dns.h"
+
+/* Main types and definitions */
+
+#define	DKIM_SIGNHEADER		"DKIM-Signature"
+					/* DKIM signature header */
+
+/* special DNS tokens */
+#define	DKIM_DNSKEYNAME		"_domainkey"
+					/* reserved DNS sub-zone */
+#define	DKIM_DNSPOLICYNAME	"_adsp"	/* reserved DNS sub-zone */
+
+/* Canonization methods */
+#define DKIM_CANON_UNKNOWN	(-1)	/* unknown method */
+#define DKIM_CANON_SIMPLE	0	/* as specified in DKIM spec */
+#define DKIM_CANON_RELAXED	1	/* as specified in DKIM spec */
+
+#define DKIM_CANON_DEFAULT	DKIM_CANON_SIMPLE
+
+/* Signature methods */
+#define DKIM_SIGN_UNKNOWN	(-2)	/* unknown method */
+#define DKIM_SIGN_DEFAULT	(-1)	/* use internal default */
+#define DKIM_SIGN_RSASHA1	0	/* an RSA-signed SHA1 digest */
+#define DKIM_SIGN_RSASHA256	1	/* an RSA-signed SHA256 digest */
+
+/* Params */
+#define DKIM_PARAM_UNKNOWN	(-1)	/* unknown */
+#define DKIM_PARAM_SIGNATURE	0	/* b */
+#define DKIM_PARAM_SIGNALG	1	/* a */
+#define DKIM_PARAM_DOMAIN	2	/* d */
+#define DKIM_PARAM_CANONALG	3	/* c */
+#define DKIM_PARAM_QUERYMETHOD	4	/* q */
+#define DKIM_PARAM_SELECTOR	5	/* s */
+#define DKIM_PARAM_HDRLIST	6	/* h */
+#define DKIM_PARAM_VERSION	7	/* v */
+#define DKIM_PARAM_IDENTITY	8	/* i */
+#define DKIM_PARAM_TIMESTAMP	9	/* t */
+#define DKIM_PARAM_EXPIRATION	10	/* x */
+#define DKIM_PARAM_COPIEDHDRS	11	/* z */
+#define DKIM_PARAM_BODYHASH	12	/* bh */
+#define DKIM_PARAM_BODYLENGTH	13	/* l */
+
+/* Errors (from OpenDKIM) */
+
+#define DKIM_SIGERROR_UNKNOWN		(-1)	/* unknown error */
+#define DKIM_SIGERROR_OK		0	/* no error */
+#define DKIM_SIGERROR_VERSION		1	/* unsupported version */
+#define DKIM_SIGERROR_DOMAIN		2	/* invalid domain (d=/i=) */
+#define DKIM_SIGERROR_EXPIRED		3	/* signature expired */
+#define DKIM_SIGERROR_FUTURE		4	/* signature in the future */
+#define DKIM_SIGERROR_TIMESTAMPS	5	/* x= < t= */
+#define DKIM_SIGERROR_UNUSED		6	/* OBSOLETE */
+#define DKIM_SIGERROR_INVALID_HC	7	/* c= invalid (header) */
+#define DKIM_SIGERROR_INVALID_BC	8	/* c= invalid (body) */
+#define DKIM_SIGERROR_MISSING_A		9	/* a= missing */
+#define DKIM_SIGERROR_INVALID_A		10	/* a= invalid */
+#define DKIM_SIGERROR_MISSING_H		11	/* h= missing */
+#define DKIM_SIGERROR_INVALID_L		12	/* l= invalid */
+#define DKIM_SIGERROR_INVALID_Q		13	/* q= invalid */
+#define DKIM_SIGERROR_INVALID_QO	14	/* q= option invalid */
+#define DKIM_SIGERROR_MISSING_D		15	/* d= missing */
+#define DKIM_SIGERROR_EMPTY_D		16	/* d= empty */
+#define DKIM_SIGERROR_MISSING_S		17	/* s= missing */
+#define DKIM_SIGERROR_EMPTY_S		18	/* s= empty */
+#define DKIM_SIGERROR_MISSING_B		19	/* b= missing */
+#define DKIM_SIGERROR_EMPTY_B		20	/* b= empty */
+#define DKIM_SIGERROR_CORRUPT_B		21	/* b= corrupt */
+#define DKIM_SIGERROR_NOKEY		22	/* no key found in DNS */
+#define DKIM_SIGERROR_DNSSYNTAX		23	/* DNS reply corrupt */
+#define DKIM_SIGERROR_KEYFAIL		24	/* DNS query failed */
+#define DKIM_SIGERROR_MISSING_BH	25	/* bh= missing */
+#define DKIM_SIGERROR_EMPTY_BH		26	/* bh= empty */
+#define DKIM_SIGERROR_CORRUPT_BH	27	/* bh= corrupt */
+#define DKIM_SIGERROR_BADSIG		28	/* signature mismatch */
+#define DKIM_SIGERROR_SUBDOMAIN		29	/* unauthorized subdomain */
+#define DKIM_SIGERROR_MULTIREPLY	30	/* multiple records returned */
+#define DKIM_SIGERROR_EMPTY_H		31	/* h= empty */
+#define DKIM_SIGERROR_INVALID_H		32	/* h= missing req'd entries */
+#define DKIM_SIGERROR_TOOLARGE_L	33	/* l= value exceeds body size */
+#define DKIM_SIGERROR_MBSFAILED		34	/* "must be signed" failure */
+#define	DKIM_SIGERROR_KEYVERSION	35	/* unknown key version */
+#define	DKIM_SIGERROR_KEYUNKNOWNHASH	36	/* unknown key hash */
+#define	DKIM_SIGERROR_KEYHASHMISMATCH	37	/* sig-key hash mismatch */
+#define	DKIM_SIGERROR_NOTEMAILKEY	38	/* not an e-mail key */
+#define	DKIM_SIGERROR_UNUSED2		39	/* OBSOLETE */
+#define	DKIM_SIGERROR_KEYTYPEMISSING	40	/* key type missing */
+#define	DKIM_SIGERROR_KEYTYPEUNKNOWN	41	/* key type unknown */
+#define	DKIM_SIGERROR_KEYREVOKED	42	/* key revoked */
+#define	DKIM_SIGERROR_KEYDECODE		43	/* key couldn't be decoded */
+#define	DKIM_SIGERROR_MISSING_V		44	/* v= tag missing */
+#define	DKIM_SIGERROR_EMPTY_V		45	/* v= tag empty */
+
+/* Check results */
+#define	DKIM_CONTINUE	0	/* continue */
+#define	DKIM_REJECT	1	/* reject */
+#define	DKIM_TRYAGAIN	2	/* try again later */
+#define	DKIM_NOTFOUND	3	/* requested record not found */
+#define	DKIM_RECORD_ERROR	4	/* error requesting record */
+
+typedef struct rspamd_dkim_context_s {
+	memory_pool_t *pool;
+	gint sig_alg;
+	gint header_canon_type;
+	gint body_canon_type;
+	gsize len;
+	gchar *domain;
+	gchar *selector;
+	time_t timestamp;
+	time_t expiration;
+	gchar *b;
+	gchar *bh;
+	GList *hlist;
+	guint ver;
+} rspamd_dkim_context_t;
+
+typedef struct rspamd_dkim_key_s {
+	memory_pool_t *pool;
+	/* TODO: make this structure */
+} rspamd_dkim_key_t;
+
+struct worker_task;
+
+/**
+ * Create new dkim context from signature
+ * @param sig message's signature
+ * @param pool pool to allocate memory from
+ * @param err pointer to error object
+ * @return new context or NULL
+ */
+rspamd_dkim_context_t* rspamd_create_dkim_context (const gchar *sig, memory_pool_t *pool, GError **err);
+
+/**
+ * Make DNS request for specified context and obtain and parse key
+ * @param ctx dkim context from signature
+ * @param resolver dns resolver object
+ * @param s async session to make request
+ * @return
+ */
+rspamd_dkim_key_t* rspamd_get_dkim_key (rspamd_dkim_context_t *ctx, struct rspamd_dns_resolver *resolver,
+		struct rspamd_async_session *s);
+
+/**
+ * Check task for dkim context using dkim key
+ * @param ctx dkim verify context
+ * @param key dkim key (from cache or from dns request)
+ * @param task task to check
+ * @return
+ */
+gint rspamd_dkim_check (rspamd_dkim_context_t *ctx, rspamd_dkim_key_t *key, struct worker_task *task);
+
+#endif /* DKIM_H_ */