This restructures lib/afs.c so that the token data can be but into a

stream. This is to implement wbinfo -k that asks winbind for authentication
which then creates the AFS token for the authenticated user.

Volker
(This used to be commit 2df6750a079820826013360fb9e47f90bc8223a5)

1 files changed, 294 insertions, 67 deletions

diff --git a/source3/lib/afs.c b/source3/lib/afs.c
index 789afcdd83..ce972ec27b 100644
--- a/source3/lib/afs.c
+++ b/source3/lib/afs.c
@@ -43,6 +43,130 @@ struct ClearToken {
 	uint32 EndTimestamp;
 };
 
+static char *afs_encode_token(const char *cell, const DATA_BLOB ticket,
+			      const struct ClearToken *ct)
+{
+	char *base64_ticket;
+	char *result;
+
+	DATA_BLOB key = data_blob(ct->HandShakeKey, 8);
+	char *base64_key;
+
+	base64_ticket = base64_encode_data_blob(ticket);
+	if (base64_ticket == NULL)
+		return NULL;
+
+	base64_key = base64_encode_data_blob(key);
+	if (base64_key == NULL) {
+		free(base64_ticket);
+		return NULL;
+	}
+
+	asprintf(&result, "%s\n%u\n%s\n%u\n%u\n%u\n%s\n", cell,
+		 ct->AuthHandle, base64_key, ct->ViceId, ct->BeginTimestamp,
+		 ct->EndTimestamp, base64_ticket);
+
+	DEBUG(10, ("Got ticket string:\n%s\n", result));
+
+	free(base64_ticket);
+	free(base64_key);
+
+	return result;
+}
+
+static BOOL afs_decode_token(const char *string, char **cell,
+			     DATA_BLOB *ticket, struct ClearToken *ct)
+{
+	DATA_BLOB blob;
+	struct ClearToken result_ct;
+
+	char *s = strdup(string);
+
+	char *t;
+
+	if ((t = strtok(s, "\n")) == NULL) {
+		DEBUG(10, ("strtok failed\n"));
+		return False;
+	}
+
+	*cell = strdup(t);
+
+	if ((t = strtok(NULL, "\n")) == NULL) {
+		DEBUG(10, ("strtok failed\n"));
+		return False;
+	}
+
+	if (sscanf(t, "%u", &result_ct.AuthHandle) != 1) {
+		DEBUG(10, ("sscanf AuthHandle failed\n"));
+		return False;
+	}
+		
+	if ((t = strtok(NULL, "\n")) == NULL) {
+		DEBUG(10, ("strtok failed\n"));
+		return False;
+	}
+
+	blob = base64_decode_data_blob(t);
+
+	if ( (blob.data == NULL) ||
+	     (blob.length != sizeof(result_ct.HandShakeKey) )) {
+		DEBUG(10, ("invalid key: %x/%d\n", (uint32)blob.data,
+			   blob.length));
+		return False;
+	}
+
+	memcpy(result_ct.HandShakeKey, blob.data, blob.length);
+
+	data_blob_free(&blob);
+
+	if ((t = strtok(NULL, "\n")) == NULL) {
+		DEBUG(10, ("strtok failed\n"));
+		return False;
+	}
+
+	if (sscanf(t, "%u", &result_ct.ViceId) != 1) {
+		DEBUG(10, ("sscanf ViceId failed\n"));
+		return False;
+	}
+		
+	if ((t = strtok(NULL, "\n")) == NULL) {
+		DEBUG(10, ("strtok failed\n"));
+		return False;
+	}
+
+	if (sscanf(t, "%u", &result_ct.BeginTimestamp) != 1) {
+		DEBUG(10, ("sscanf BeginTimestamp failed\n"));
+		return False;
+	}
+		
+	if ((t = strtok(NULL, "\n")) == NULL) {
+		DEBUG(10, ("strtok failed\n"));
+		return False;
+	}
+
+	if (sscanf(t, "%u", &result_ct.EndTimestamp) != 1) {
+		DEBUG(10, ("sscanf EndTimestamp failed\n"));
+		return False;
+	}
+		
+	if ((t = strtok(NULL, "\n")) == NULL) {
+		DEBUG(10, ("strtok failed\n"));
+		return False;
+	}
+
+	blob = base64_decode_data_blob(t);
+
+	if (blob.data == NULL) {
+		DEBUG(10, ("Could not get ticket\n"));
+		return False;
+	}
+
+	*ticket = blob;
+	*ct = result_ct;
+
+	return True;
+}
+
 /*
   Put an AFS token into the Kernel so that it can authenticate against
   the AFS server. This assumes correct local uid settings.
@@ -53,9 +177,9 @@ struct ClearToken {
   to avoid. 
 */
 
-static BOOL afs_settoken(const char *username, const char *cell,
+static BOOL afs_settoken(const char *cell,
 			 const struct ClearToken *ctok,
-			 char *v4tkt_data, int v4tkt_length)
+			 DATA_BLOB ticket)
 {
 	int ret;
 	struct {
@@ -67,10 +191,10 @@ static BOOL afs_settoken(const char *username, const char *cell,
 	char *p = buf;
 	int tmp;
 
-	memcpy(p, &v4tkt_length, sizeof(uint32));
+	memcpy(p, &ticket.length, sizeof(uint32));
 	p += sizeof(uint32);
-	memcpy(p, v4tkt_data, v4tkt_length);
-	p += v4tkt_length;
+	memcpy(p, ticket.data, ticket.length);
+	p += ticket.length;
 
 	tmp = sizeof(struct ClearToken);
 	memcpy(p, &tmp, sizeof(uint32));
@@ -109,90 +233,69 @@ static BOOL afs_settoken(const char *username, const char *cell,
 	return (ret == 0);
 }
 
-/*
-  This routine takes a radical approach completely defeating the
-  Kerberos idea of security and using AFS simply as an intelligent
-  file backend. Samba has persuaded itself somehow that the user is
-  actually correctly identified and then we create a ticket that the
-  AFS server hopefully accepts using its KeyFile that the admin has
-  kindly stored to our secrets.tdb.
-
-  Thanks to the book "Network Security -- PRIVATE Communication in a
-  PUBLIC World" by Charlie Kaufman, Radia Perlman and Mike Speciner
-  Kerberos 4 tickets are not really hard to construct.
-
-  For the comments "Alice" is the User to be auth'ed, and "Bob" is the
-  AFS server.  */
-
-BOOL afs_login(connection_struct *conn)
+BOOL afs_settoken_str(const char *token_string)
 {
-	fstring ticket;
-	char *p = ticket;
-	uint32 len;
-	struct afs_key key;
-	pstring afs_username;
-	char *cell;
-
+	DATA_BLOB ticket;
 	struct ClearToken ct;
+	BOOL result;
+	char *cell;
 
-	uint32 now;		/* I assume time() returns 32 bit */
+	if (!afs_decode_token(token_string, &cell, &ticket, &ct))
+		return False;
 
-	des_key_schedule key_schedule;
+	if (geteuid() != 0)
+		ct.ViceId = getuid();
 
-	pstrcpy(afs_username, lp_afs_username_map());
-	standard_sub_conn(conn, afs_username, sizeof(afs_username));
+	result = afs_settoken(cell, &ct, ticket);
 
-	/* The pts command always generates completely lower-case user
-	 * names. */
-	strlower_m(afs_username);
+	SAFE_FREE(cell);
+	data_blob_free(&ticket);
 
-	cell = strchr(afs_username, '@');
-
-	if (cell == NULL) {
-		DEBUG(1, ("AFS username doesn't contain a @, "
-			  "could not find cell\n"));
-		return False;
+	return result;
 	}
 
-	*cell = '\0';
-	cell += 1;
+/* Create a ClearToken and an encrypted ticket. ClearToken has not yet the
+ * ViceId set, this should be set by the caller. */
 
-	DEBUG(10, ("Trying to log into AFS for user %s@%s\n", 
-		   afs_username, cell));
+static BOOL afs_createtoken(const char *username, const char *cell,
+			    DATA_BLOB *ticket, struct ClearToken *ct)
+{
+	fstring clear_ticket;
+	char *p = clear_ticket;
+	uint32 len;
+	uint32 now;
+
+	struct afs_key key;
+	des_key_schedule key_schedule;
 
 	if (!secrets_init()) 
 		return False;
 
 	if (!secrets_fetch_afs_key(cell, &key)) {
-		DEBUG(5, ("Could not fetch AFS service key\n"));
+		DEBUG(1, ("Could not fetch AFS service key\n"));
 		return False;
 	}
 
-	ct.AuthHandle = key.kvno;
+	ct->AuthHandle = key.kvno;
 
 	/* Build the ticket. This is going to be encrypted, so in our
            way we fill in ct while we still have the unencrypted
            form. */
 
-	p = ticket;
+	p = clear_ticket;
 
 	/* The byte-order */
 	*p = 1;
 	p += 1;
 
 	/* "Alice", the client username */
-	strncpy(p, afs_username, sizeof(ticket)-PTR_DIFF(p,ticket)-1);
+	strncpy(p, username, sizeof(clear_ticket)-PTR_DIFF(p,clear_ticket)-1);
 	p += strlen(p)+1;
-	strncpy(p, "", sizeof(ticket)-PTR_DIFF(p,ticket)-1);
+	strncpy(p, "", sizeof(clear_ticket)-PTR_DIFF(p,clear_ticket)-1);
 	p += strlen(p)+1;
-	strncpy(p, cell, sizeof(ticket)-PTR_DIFF(p,ticket)-1);
+	strncpy(p, cell, sizeof(clear_ticket)-PTR_DIFF(p,clear_ticket)-1);
 	p += strlen(p)+1;
 
-	/* This assumes that we have setresuid and set the real uid as well as
-	   the effective uid in set_effective_uid(). */
-	ct.ViceId = getuid();
-	DEBUG(10, ("Creating Token for uid %d\n", ct.ViceId));
-
 	/* Alice's network layer address. At least Openafs-1.2.10
            ignores this, so we fill in a dummy value here. */
 	SIVAL(p, 0, 0);
@@ -203,7 +306,7 @@ BOOL afs_login(connection_struct *conn)
 
 	/* Our client code needs the the key in the clear, it does not
            know the server-key ... */
-	memcpy(ct.HandShakeKey, p, 8);
+	memcpy(ct->HandShakeKey, p, 8);
 
 	p += 8;
 
@@ -216,37 +319,151 @@ BOOL afs_login(connection_struct *conn)
 	/* Ticket creation time */
 	now = time(NULL);
 	SIVAL(p, 0, now);
-	ct.BeginTimestamp = now;
+	ct->BeginTimestamp = now;
 
-	ct.EndTimestamp = now + (255*60*5);
-	if (((ct.EndTimestamp - ct.BeginTimestamp) & 1) == 1) {
-		ct.BeginTimestamp += 1; /* Lifetime must be even */
+	ct->EndTimestamp = now + (255*60*5);
+	if (((ct->EndTimestamp - ct->BeginTimestamp) & 1) == 1) {
+		ct->BeginTimestamp += 1; /* Lifetime must be even */
 	}
 	p += 4;
 
 	/* And here comes Bob's name and instance, in this case the
            AFS server. */
-	strncpy(p, "afs", sizeof(ticket)-PTR_DIFF(p,ticket)-1);
+	strncpy(p, "afs", sizeof(clear_ticket)-PTR_DIFF(p,clear_ticket)-1);
 	p += strlen(p)+1;
-	strncpy(p, "", sizeof(ticket)-PTR_DIFF(p,ticket)-1);
+	strncpy(p, "", sizeof(clear_ticket)-PTR_DIFF(p,clear_ticket)-1);
 	p += strlen(p)+1;
 
 	/* And zero-pad to a multiple of 8 bytes */
-	len = PTR_DIFF(p, ticket);
+	len = PTR_DIFF(p, clear_ticket);
 	if (len & 7) {
 		uint32 extra_space = 8-(len & 7);
 		memset(p, 0, extra_space);
 		p+=extra_space;
 	}
-	len = PTR_DIFF(p, ticket);
+	len = PTR_DIFF(p, clear_ticket);
 
 	des_key_sched((const_des_cblock *)key.key, key_schedule);
-	des_pcbc_encrypt(ticket, ticket,
+	des_pcbc_encrypt(clear_ticket, clear_ticket,
 			 len, key_schedule, (C_Block *)key.key, 1);
 
 	ZERO_STRUCT(key);
 
-	return afs_settoken(afs_username, cell, &ct, ticket, len);
+	*ticket = data_blob(clear_ticket, len);
+
+	return True;
+}
+
+char *afs_createtoken_str(const char *username, const char *cell)
+{
+	DATA_BLOB ticket;
+	struct ClearToken ct;
+	char *result;
+
+	if (!afs_createtoken(username, cell, &ticket, &ct))
+		return NULL;
+
+	result = afs_encode_token(cell, ticket, &ct);
+
+	data_blob_free(&ticket);
+
+	return result;
+}
+
+/*
+  This routine takes a radical approach completely bypassing the
+  Kerberos idea of security and using AFS simply as an intelligent
+  file backend. Samba has persuaded itself somehow that the user is
+  actually correctly identified and then we create a ticket that the
+  AFS server hopefully accepts using its KeyFile that the admin has
+  kindly stored to our secrets.tdb.
+
+  Thanks to the book "Network Security -- PRIVATE Communication in a
+  PUBLIC World" by Charlie Kaufman, Radia Perlman and Mike Speciner
+  Kerberos 4 tickets are not really hard to construct.
+
+  For the comments "Alice" is the User to be auth'ed, and "Bob" is the
+  AFS server.  */
+
+BOOL afs_login(connection_struct *conn)
+{
+	DATA_BLOB ticket;
+	pstring afs_username;
+	char *cell;
+	BOOL result;
+
+	struct ClearToken ct;
+
+	pstrcpy(afs_username, lp_afs_username_map());
+	standard_sub_conn(conn, afs_username, sizeof(afs_username));
+
+	/* The pts command always generates completely lower-case user
+	 * names. */
+	strlower_m(afs_username);
+
+	cell = strchr(afs_username, '@');
+
+	if (cell == NULL) {
+		DEBUG(1, ("AFS username doesn't contain a @, "
+			  "could not find cell\n"));
+		return False;
+	}
+
+	*cell = '\0';
+	cell += 1;
+
+	DEBUG(10, ("Trying to log into AFS for user %s@%s\n", 
+		   afs_username, cell));
+
+	if (!afs_createtoken(afs_username, cell, &ticket, &ct))
+		return False;
+
+	/* For which Unix-UID do we want to set the token? */
+	ct.ViceId = getuid();
+
+	{
+		char *str, *new_cell;
+		DATA_BLOB test_ticket;
+		struct ClearToken test_ct;
+
+		hex_encode(ct.HandShakeKey, sizeof(ct.HandShakeKey), &str);
+		DEBUG(10, ("Key: %s\n", str));
+		free(str);
+
+		str = afs_encode_token(cell, ticket, &ct);
+
+		if (!afs_decode_token(str, &new_cell, &test_ticket,
+				      &test_ct)) {
+			DEBUG(0, ("Could not decode token"));
+			goto decode_failed;
+		}
+
+		if (strcmp(cell, new_cell) != 0) {
+			DEBUG(0, ("cell changed\n"));
+		}
+
+		if ((ticket.length != test_ticket.length) ||
+		    (memcmp(ticket.data, test_ticket.data,
+			    ticket.length) != 0)) {
+			DEBUG(0, ("Ticket changed\n"));
+		}
+
+		if (memcmp(&ct, &test_ct, sizeof(ct)) != 0) {
+			DEBUG(0, ("ClearToken changed\n"));
+		}
+
+		data_blob_free(&test_ticket);
+
+	decode_failed:
+		SAFE_FREE(str);
+		SAFE_FREE(new_cell);
+	}
+
+	result = afs_settoken(cell, &ct, ticket);
+
+	data_blob_free(&ticket);
+
+	return result;
 }
 
 #else
@@ -256,4 +473,14 @@ BOOL afs_login(connection_struct *conn)
 	return True;
 }
 
+BOOL afs_settoken_str(const char *token_string)
+{
+	return False;
+}
+
+char *afs_createtoken_str(const char *username, const char *cell)
+{
+	return False;
+}
+
 #endif /* WITH_FAKE_KASERVER */