-/* $Cambridge: exim/src/src/auths/dovecot.c,v 1.6 2007/01/25 16:23:42 ph10 Exp $ */
-
/*
* Copyright (c) 2004 Andrey Panin <pazke@donpac.ru>
*
* (at your option) any later version.
*/
+/* A number of modifications have been made to the original code. Originally I
+commented them specially, but now they are getting quite extensive, so I have
+ceased doing that. The biggest change is to use unbuffered I/O on the socket
+because using C buffered I/O gives problems on some operating systems. PH */
+
#include "../exim.h"
#include "dovecot.h"
/* Options specific to the authentication mechanism. */
optionlist auth_dovecot_options[] = {
{
- "server_socket",
- opt_stringptr,
- (void *)(offsetof(auth_dovecot_options_block, server_socket))
+ "server_socket",
+ opt_stringptr,
+ (void *)(offsetof(auth_dovecot_options_block, server_socket))
},
};
/* Size of the options list. An extern variable has to be used so that its
address can appear in the tables drtables.c. */
+
int auth_dovecot_options_count =
sizeof(auth_dovecot_options) / sizeof(optionlist);
/* Default private options block for the authentication method. */
+
auth_dovecot_options_block auth_dovecot_option_defaults = {
NULL, /* server_socket */
};
+
+/* Static variables for reading from the socket */
+
+static uschar sbuffer[256];
+static int sbp;
+
+
+
/*************************************************
* Initialization entry point *
*************************************************/
/* Called for each instance, after its options have been read, to
enable consistency checks to be done, or anything else that needs
to be set up. */
+
void auth_dovecot_init(auth_instance *ablock)
{
auth_dovecot_options_block *ob =
ablock->client = FALSE;
}
-static int strcut(char *str, char **ptrs, int nptrs)
+static int strcut(uschar *str, uschar **ptrs, int nptrs)
{
- char *tmp = str;
+ uschar *tmp = str;
int n;
for (n = 0; n < nptrs; n++)
}
#define CHECK_COMMAND(str, arg_min, arg_max) do { \
- if (strcasecmp((str), args[0]) != 0) \
+ if (strcmpic(US(str), args[0]) != 0) \
goto out; \
if (nargs - 1 < (arg_min)) \
goto out; \
- if (nargs - 1 > (arg_max)) \
+ if ( (arg_max != -1) && (nargs - 1 > (arg_max)) ) \
goto out; \
} while (0)
/*************************************************
- * Server entry point *
- *************************************************/
+* "fgets" to read directly from socket *
+*************************************************/
+
+/* Added by PH after a suggestion by Steve Usher because the previous use of
+C-style buffered I/O gave trouble. */
+
+static uschar *
+dc_gets(uschar *s, int n, int fd)
+{
+int p = 0;
+int count = 0;
+
+for (;;)
+ {
+ if (sbp == 0)
+ {
+ sbp = read(fd, sbuffer, sizeof(sbuffer));
+ if (sbp == 0) { if (count == 0) return NULL; else break; }
+ p = 0;
+ }
+
+ while (p < sbp)
+ {
+ if (count >= n - 1) break;
+ s[count++] = sbuffer[p];
+ if (sbuffer[p++] == '\n') break;
+ }
+
+ memmove(sbuffer, sbuffer + p, sbp - p);
+ sbp -= p;
+
+ if (s[count-1] == '\n' || count >= n - 1) break;
+ }
+
+s[count] = 0;
+return s;
+}
+
+
+
+
+/*************************************************
+* Server entry point *
+*************************************************/
int auth_dovecot_server(auth_instance *ablock, uschar *data)
{
auth_dovecot_options_block *ob =
(auth_dovecot_options_block *)(ablock->options_block);
struct sockaddr_un sa;
- char buffer[4096];
- char *args[8];
+ uschar buffer[4096];
+ uschar *args[8];
uschar *auth_command;
uschar *auth_extra_data = US"";
int nargs, tmp;
int cuid = 0, cont = 1, found = 0, fd, ret = DEFER;
- FILE *f;
HDEBUG(D_auth) debug_printf("dovecot authentication\n");
if (connect(fd, (struct sockaddr *) &sa, sizeof(sa)) < 0)
goto out;
- f = fdopen(fd, "a+");
- if (f == NULL)
- goto out;
-
auth_defer_msg = US"authentication socket protocol error";
+ sbp = 0; /* Socket buffer pointer */
while (cont) {
- if (fgets(buffer, sizeof(buffer), f) == NULL)
+ if (dc_gets(buffer, sizeof(buffer), fd) == NULL)
OUT("authentication socket read error or premature eof");
- buffer[strlen(buffer) - 1] = 0;
+ buffer[Ustrlen(buffer) - 1] = 0;
HDEBUG(D_auth) debug_printf("received: %s\n", buffer);
nargs = strcut(buffer, args, sizeof(args) / sizeof(args[0]));
- switch (toupper(*args[0])) {
- case 'C':
+ /* Code below rewritten by Kirill Miazine (km@krot.org). Only check commands that
+ Exim will need. Original code also failed if Dovecot server sent unknown
+ command. E.g. COOKIE in version 1.1 of the protocol would cause troubles. */
+ if (Ustrcmp(args[0], US"CUID") == 0) {
CHECK_COMMAND("CUID", 1, 1);
- cuid = atoi(args[1]);
- break;
-
- case 'D':
- CHECK_COMMAND("DONE", 0, 0);
- cont = 0;
- break;
-
- case 'M':
+ cuid = Uatoi(args[1]);
+ } else if (Ustrcmp(args[0], US"VERSION") == 0) {
+ CHECK_COMMAND("VERSION", 2, 2);
+ if (Uatoi(args[1]) != VERSION_MAJOR)
+ OUT("authentication socket protocol version mismatch");
+ } else if (Ustrcmp(args[0], US"MECH") == 0) {
CHECK_COMMAND("MECH", 1, INT_MAX);
if (strcmpic(US args[1], ablock->public_name) == 0)
found = 1;
- break;
-
- case 'S':
- CHECK_COMMAND("SPID", 1, 1);
- break;
-
- case 'V':
- CHECK_COMMAND("VERSION", 2, 2);
- if (atoi(args[1]) != VERSION_MAJOR)
- OUT("authentication socket protocol version mismatch");
- break;
-
- default:
- goto out;
+ } else if (Ustrcmp(args[0], US"DONE") == 0) {
+ CHECK_COMMAND("DONE", 0, 0);
+ cont = 0;
}
}
Subsequently, the command was modified to add "secured" and "valid-client-
cert" when relevant.
+
+ The auth protocol is documented here:
+ http://wiki.dovecot.org/Authentication_Protocol
****************************************************************************/
auth_command = string_sprintf("VERSION\t%d\t%d\nCPID\t%d\n"
- "AUTH\t%d\t%s\tservice=smtp\t%srip=%s\tlip=%s\tresp=%s\n",
+ "AUTH\t%d\t%s\tservice=smtp\t%srip=%s\tlip=%s\tnologin\tresp=%s\n",
VERSION_MAJOR, VERSION_MINOR, getpid(), cuid,
ablock->public_name, auth_extra_data, sender_host_address,
interface_address, data ? (char *) data : "");
- fprintf(f, "%s", auth_command);
+ if (write(fd, auth_command, Ustrlen(auth_command)) < 0)
+ HDEBUG(D_auth) debug_printf("error sending auth_command: %s\n",
+ strerror(errno));
+
HDEBUG(D_auth) debug_printf("sent: %s", auth_command);
while (1) {
- if (fgets(buffer, sizeof(buffer), f) == NULL) {
+ uschar *temp;
+ uschar *auth_id_pre = NULL;
+ int i;
+
+ if (dc_gets(buffer, sizeof(buffer), fd) == NULL) {
auth_defer_msg = US"authentication socket read error or premature eof";
goto out;
}
- buffer[strlen(buffer) - 1] = 0;
+ buffer[Ustrlen(buffer) - 1] = 0;
HDEBUG(D_auth) debug_printf("received: %s\n", buffer);
nargs = strcut(buffer, args, sizeof(args) / sizeof(args[0]));
- if (atoi(args[1]) != cuid)
+ if (Uatoi(args[1]) != cuid)
OUT("authentication socket connection id mismatch");
switch (toupper(*args[0])) {
goto out;
}
- if (fprintf(f, "CONT\t%d\t%s\r\n", cuid, data) < 0)
+ temp = string_sprintf("CONT\t%d\t%s\n", cuid, data);
+ if (write(fd, temp, Ustrlen(temp)) < 0)
OUT("authentication socket write error");
-
break;
case 'F':
- CHECK_COMMAND("FAIL", 1, 2);
+ CHECK_COMMAND("FAIL", 1, -1);
- /* FIXME: add proper response handling */
- if (args[2]) {
- uschar *p = US strchr(args[2], '=');
- if (p) {
- ++p;
+ for (i=2; (i<nargs) && (auth_id_pre == NULL); i++)
+ {
+ if ( Ustrncmp(args[i], US"user=", 5) == 0 )
+ {
+ auth_id_pre = args[i]+5;
expand_nstring[1] = auth_vars[0] =
- string_copy(p); /* PH */
- expand_nlength[1] = Ustrlen(p);
+ string_copy(auth_id_pre); /* PH */
+ expand_nlength[1] = Ustrlen(auth_id_pre);
expand_nmax = 1;
}
}
goto out;
case 'O':
- CHECK_COMMAND("OK", 2, 2);
+ CHECK_COMMAND("OK", 2, -1);
+
+ /*
+ * Search for the "user=$USER" string in the args array
+ * and return the proper value.
+ */
+ for (i=2; (i<nargs) && (auth_id_pre == NULL); i++)
{
- /* FIXME: add proper response handling */
- uschar *p = US strchr(args[2], '=');
- if (!p)
- OUT("authentication socket protocol error, username missing");
-
- p++;
- expand_nstring[1] = auth_vars[0] =
- string_copy(p); /* PH */
- expand_nlength[1] = Ustrlen(p);
- expand_nmax = 1;
+ if ( Ustrncmp(args[i], US"user=", 5) == 0 )
+ {
+ auth_id_pre = args[i]+5;
+ expand_nstring[1] = auth_vars[0] =
+ string_copy(auth_id_pre); /* PH */
+ expand_nlength[1] = Ustrlen(auth_id_pre);
+ expand_nmax = 1;
+ }
}
+
+ if (auth_id_pre == NULL)
+ OUT("authentication socket protocol error, username missing");
+
ret = OK;
/* fallthrough */
}
}
-out: close(fd);
+out:
+ /* close the socket used by dovecot */
+ if (fd >= 0)
+ close(fd);
/* Expand server_condition as an authorization check */
return (ret == OK)? auth_check_serv_cond(ablock) : ret;