NetBSD/crypto/dist/krb4/appl/movemail/pop.c

1367 lines
29 KiB
C

/* pop.c: client routines for talking to a POP3-protocol post-office server
Copyright (c) 1991,1993 Free Software Foundation, Inc.
Written by Jonathan Kamens, jik@security.ov.com.
This file is part of GNU Emacs.
GNU Emacs is free software; you can redistribute it and/or modify
it under the terms of the GNU General Public License as published by
the Free Software Foundation; either version 2, or (at your option)
any later version.
GNU Emacs is distributed in the hope that it will be useful,
but WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
GNU General Public License for more details.
You should have received a copy of the GNU General Public License
along with GNU Emacs; see the file COPYING. If not, write to
the Free Software Foundation, 675 Mass Ave, Cambridge, MA 02139, USA. */
#ifdef HAVE_CONFIG_H
#include <config.h>
#include <protos.h>
#endif
#include <stdlib.h>
#include <string.h>
#ifdef HAVE_UNISTD_H
#include <unistd.h>
#endif
#ifdef HAVE_SYS_TYPES_H
#include <sys/types.h>
#endif
#ifdef HAVE_NETINET_IN_H
#include <netinet/in.h>
#endif
#ifdef HAVE_SYS_SOCKET_H
#include <sys/socket.h>
#endif
#include <pop.h>
#ifdef HESIOD
#include <hesiod.h>
/*
* It really shouldn't be necessary to put this declaration here, but
* the version of hesiod.h that Athena has installed in release 7.2
* doesn't declare this function; I don't know if the 7.3 version of
* hesiod.h does.
*/
extern struct servent *hes_getservbyname (/* char *, char * */);
#endif
#ifdef HAVE_PWD_H
#include <pwd.h>
#endif
#ifdef HAVE_NETDB_H
#include <netdb.h>
#endif
#include <errno.h>
#ifdef SOCKS
#include <socks.h>
/* This doesn't belong here. */
struct tm *localtime(const time_t *);
struct hostent *gethostbyname(const char *);
#endif
#include <des.h>
#include <krb.h>
#include <roken.h>
static int socket_connection ( char *, int );
static char *pop_getline ( popserver );
static int sendline ( popserver, char * );
static int fullwrite ( int, char *, int );
static int getok ( popserver );
#if 0
static int gettermination ( popserver );
#endif
static void pop_trash ( popserver );
static char *find_crlf ( char * );
#if defined(__ultrix) || IRIX == 4
char *getpass(const char*);
#endif
#define ERROR_MAX 80 /* a pretty arbitrary size */
#define POP_PORT 110
#define KPOP_PORT 1109
#define POP_SERVICE "pop"
#define KPOP_SERVICE "kpop"
char pop_error[ERROR_MAX];
int pop_debug = 0;
/*
* Function: pop_open (char *host, char *username, char *password,
* int flags)
*
* Purpose: Establishes a connection with a post-office server, and
* completes the authorization portion of the session.
*
* Arguments:
* host The server host with which the connection should be
* established. Optional. If omitted, internal
* heuristics will be used to determine the server host,
* if possible.
* username
* The username of the mail-drop to access. Optional.
* If omitted, internal heuristics will be used to
* determine the username, if possible.
* password
* The password to use for authorization. If omitted,
* internal heuristics will be used to determine the
* password, if possible.
* flags A bit mask containing flags controlling certain
* functions of the routine. Valid flags are defined in
* the file pop.h
*
* Return value: Upon successful establishment of a connection, a
* non-null popserver will be returned. Otherwise, null will be
* returned, and the string variable pop_error will contain an
* explanation of the error.
*/
popserver
pop_open (host, username, password, flags)
char *host;
char *username;
char *password;
int flags;
{
int sock;
popserver server;
/* Determine the user name */
if (! username)
{
username = getenv ("USER");
if (! (username && *username))
{
username = getlogin ();
if (! (username && *username))
{
struct passwd *passwd;
passwd = getpwuid (getuid ());
if (passwd && passwd->pw_name && *passwd->pw_name)
{
username = passwd->pw_name;
}
else
{
strcpy (pop_error, "Could not determine username");
return (0);
}
}
}
}
/*
* Determine the mail host.
*/
if (! host)
{
host = getenv ("MAILHOST");
}
#ifdef HESIOD
if ((! host) && (! (flags & POP_NO_HESIOD)))
{
struct hes_postoffice *office;
office = hes_getmailhost (username);
if (office && office->po_type && (! strcmp (office->po_type, "POP"))
&& office->po_name && *office->po_name && office->po_host
&& *office->po_host)
{
host = office->po_host;
username = office->po_name;
}
}
#endif
#ifdef MAILHOST
if (! host)
{
host = MAILHOST;
}
#endif
if (! host)
{
strcpy (pop_error, "Could not determine POP server");
return (0);
}
/* Determine the password */
#define DONT_NEED_PASSWORD (! (flags & POP_NO_KERBEROS))
if ((! password) && (! DONT_NEED_PASSWORD))
{
if (! (flags & POP_NO_GETPASS))
{
password = getpass ("Enter POP password:");
}
if (! password)
{
strcpy (pop_error, "Could not determine POP password");
return (0);
}
}
if (password)
flags |= POP_NO_KERBEROS;
else
password = username;
sock = socket_connection (host, flags);
if (sock == -1)
return (0);
server = (popserver) malloc (sizeof (struct _popserver));
if (! server)
{
strcpy (pop_error, "Out of memory in pop_open");
return (0);
}
server->buffer = (char *) malloc (GETLINE_MIN);
if (! server->buffer)
{
strcpy (pop_error, "Out of memory in pop_open");
free (server);
return (0);
}
server->file = sock;
server->data = 0;
server->buffer_index = 0;
server->buffer_size = GETLINE_MIN;
server->in_multi = 0;
if (getok (server))
return (0);
/*
* I really shouldn't use the pop_error variable like this, but....
*/
if (strlen (username) > ERROR_MAX - 6)
{
pop_close (server);
strcpy (pop_error,
"Username too long; recompile pop.c with larger ERROR_MAX");
return (0);
}
sprintf (pop_error, "USER %s", username);
if (sendline (server, pop_error) || getok (server))
{
return (0);
}
if (strlen (password) > ERROR_MAX - 6)
{
pop_close (server);
strcpy (pop_error,
"Password too long; recompile pop.c with larger ERROR_MAX");
return (0);
}
sprintf (pop_error, "PASS %s", password);
if (sendline (server, pop_error) || getok (server))
{
return (0);
}
return (server);
}
/*
* Function: pop_stat
*
* Purpose: Issue the STAT command to the server and return (in the
* value parameters) the number of messages in the maildrop and
* the total size of the maildrop.
*
* Return value: 0 on success, or non-zero with an error in pop_error
* in failure.
*
* Side effects: On failure, may make further operations on the
* connection impossible.
*/
int
pop_stat (server, count, size)
popserver server;
int *count;
int *size;
{
char *fromserver;
if (server->in_multi)
{
strcpy (pop_error, "In multi-line query in pop_stat");
return (-1);
}
if (sendline (server, "STAT") || (! (fromserver = pop_getline (server))))
return (-1);
if (strncmp (fromserver, "+OK ", 4))
{
if (0 == strncmp (fromserver, "-ERR", 4))
{
strncpy (pop_error, fromserver, ERROR_MAX);
}
else
{
strcpy (pop_error,
"Unexpected response from POP server in pop_stat");
pop_trash (server);
}
return (-1);
}
*count = atoi (&fromserver[4]);
fromserver = strchr (&fromserver[4], ' ');
if (! fromserver)
{
strcpy (pop_error,
"Badly formatted response from server in pop_stat");
pop_trash (server);
return (-1);
}
*size = atoi (fromserver + 1);
return (0);
}
/*
* Function: pop_list
*
* Purpose: Performs the POP "list" command and returns (in value
* parameters) two malloc'd zero-terminated arrays -- one of
* message IDs, and a parallel one of sizes.
*
* Arguments:
* server The pop connection to talk to.
* message The number of the one message about which to get
* information, or 0 to get information about all
* messages.
*
* Return value: 0 on success, non-zero with error in pop_error on
* failure.
*
* Side effects: On failure, may make further operations on the
* connection impossible.
*/
int
pop_list (server, message, IDs, sizes)
popserver server;
int message;
int **IDs;
int **sizes;
{
int how_many, i;
char *fromserver;
if (server->in_multi)
{
strcpy (pop_error, "In multi-line query in pop_list");
return (-1);
}
if (message)
how_many = 1;
else
{
int count, size;
if (pop_stat (server, &count, &size))
return (-1);
how_many = count;
}
*IDs = (int *) malloc ((how_many + 1) * sizeof (int));
*sizes = (int *) malloc ((how_many + 1) * sizeof (int));
if (! (*IDs && *sizes))
{
strcpy (pop_error, "Out of memory in pop_list");
return (-1);
}
if (message)
{
sprintf (pop_error, "LIST %d", message);
if (sendline (server, pop_error))
{
free (*IDs);
free (*sizes);
return (-1);
}
if (! (fromserver = pop_getline (server)))
{
free (*IDs);
free (*sizes);
return (-1);
}
if (strncmp (fromserver, "+OK ", 4))
{
if (! strncmp (fromserver, "-ERR", 4))
strncpy (pop_error, fromserver, ERROR_MAX);
else
{
strcpy (pop_error,
"Unexpected response from server in pop_list");
pop_trash (server);
}
free (*IDs);
free (*sizes);
return (-1);
}
(*IDs)[0] = atoi (&fromserver[4]);
fromserver = strchr (&fromserver[4], ' ');
if (! fromserver)
{
strcpy (pop_error,
"Badly formatted response from server in pop_list");
pop_trash (server);
free (*IDs);
free (*sizes);
return (-1);
}
(*sizes)[0] = atoi (fromserver);
(*IDs)[1] = (*sizes)[1] = 0;
return (0);
}
else
{
if (pop_multi_first (server, "LIST", &fromserver))
{
free (*IDs);
free (*sizes);
return (-1);
}
for (i = 0; i < how_many; i++)
{
if (pop_multi_next (server, &fromserver))
{
free (*IDs);
free (*sizes);
return (-1);
}
(*IDs)[i] = atoi (fromserver);
fromserver = strchr (fromserver, ' ');
if (! fromserver)
{
strcpy (pop_error,
"Badly formatted response from server in pop_list");
free (*IDs);
free (*sizes);
pop_trash (server);
return (-1);
}
(*sizes)[i] = atoi (fromserver);
}
if (pop_multi_next (server, &fromserver))
{
free (*IDs);
free (*sizes);
return (-1);
}
else if (fromserver)
{
strcpy (pop_error,
"Too many response lines from server in pop_list");
free (*IDs);
free (*sizes);
return (-1);
}
(*IDs)[i] = (*sizes)[i] = 0;
return (0);
}
}
/*
* Function: pop_retrieve
*
* Purpose: Retrieve a specified message from the maildrop.
*
* Arguments:
* server The server to retrieve from.
* message The message number to retrieve.
* markfrom
* If true, then mark the string "From " at the beginning
* of lines with '>'.
*
* Return value: A string pointing to the message, if successful, or
* null with pop_error set if not.
*
* Side effects: May kill connection on error.
*/
char *
pop_retrieve (server, message, markfrom)
popserver server;
int message;
int markfrom;
{
int *IDs, *sizes, bufsize, fromcount = 0, cp = 0;
char *ptr, *fromserver;
int ret;
if (server->in_multi)
{
strcpy (pop_error, "In multi-line query in pop_retrieve");
return (0);
}
if (pop_list (server, message, &IDs, &sizes))
return (0);
if (pop_retrieve_first (server, message, &fromserver))
{
return (0);
}
/*
* The "5" below is an arbitrary constant -- I assume that if
* there are "From" lines in the text to be marked, there
* probably won't be more than 5 of them. If there are, I
* allocate more space for them below.
*/
bufsize = sizes[0] + (markfrom ? 5 : 0);
ptr = malloc (bufsize);
free (IDs);
free (sizes);
if (! ptr)
{
strcpy (pop_error, "Out of memory in pop_retrieve");
pop_retrieve_flush (server);
return (0);
}
while (! (ret = pop_retrieve_next (server, &fromserver)))
{
int linesize;
if (! fromserver)
{
ptr[cp] = '\0';
return (ptr);
}
if (markfrom && fromserver[0] == 'F' && fromserver[1] == 'r' &&
fromserver[2] == 'o' && fromserver[3] == 'm' &&
fromserver[4] == ' ')
{
if (++fromcount == 5)
{
bufsize += 5;
ptr = realloc (ptr, bufsize);
if (! ptr)
{
strcpy (pop_error, "Out of memory in pop_retrieve");
pop_retrieve_flush (server);
return (0);
}
fromcount = 0;
}
ptr[cp++] = '>';
}
linesize = strlen (fromserver);
memcpy (&ptr[cp], fromserver, linesize);
cp += linesize;
ptr[cp++] = '\n';
}
if (ret)
{
free (ptr);
return (0);
}
return (0);
}
int
pop_retrieve_first (server, message, response)
popserver server;
int message;
char **response;
{
sprintf (pop_error, "RETR %d", message);
return (pop_multi_first (server, pop_error, response));
}
int
pop_retrieve_next (server, line)
popserver server;
char **line;
{
return (pop_multi_next (server, line));
}
int
pop_retrieve_flush (server)
popserver server;
{
return (pop_multi_flush (server));
}
int
pop_top_first (server, message, lines, response)
popserver server;
int message, lines;
char **response;
{
sprintf (pop_error, "TOP %d %d", message, lines);
return (pop_multi_first (server, pop_error, response));
}
int
pop_top_next (server, line)
popserver server;
char **line;
{
return (pop_multi_next (server, line));
}
int
pop_top_flush (server)
popserver server;
{
return (pop_multi_flush (server));
}
int
pop_multi_first (server, command, response)
popserver server;
char *command;
char **response;
{
if (server->in_multi)
{
strcpy (pop_error,
"Already in multi-line query in pop_multi_first");
return (-1);
}
if (sendline (server, command) || (! (*response = pop_getline (server))))
{
return (-1);
}
if (0 == strncmp (*response, "-ERR", 4))
{
strncpy (pop_error, *response, ERROR_MAX);
return (-1);
}
else if (0 == strncmp (*response, "+OK", 3))
{
for (*response += 3; **response == ' '; (*response)++) /* empty */;
server->in_multi = 1;
return (0);
}
else
{
strcpy (pop_error,
"Unexpected response from server in pop_multi_first");
return (-1);
}
}
int
pop_multi_next (server, line)
popserver server;
char **line;
{
char *fromserver;
if (! server->in_multi)
{
strcpy (pop_error, "Not in multi-line query in pop_multi_next");
return (-1);
}
fromserver = pop_getline (server);
if (! fromserver)
{
return (-1);
}
if (fromserver[0] == '.')
{
if (! fromserver[1])
{
*line = 0;
server->in_multi = 0;
return (0);
}
else
{
*line = fromserver + 1;
return (0);
}
}
else
{
*line = fromserver;
return (0);
}
}
int
pop_multi_flush (server)
popserver server;
{
char *line;
if (! server->in_multi)
{
return (0);
}
while (! pop_multi_next (server, &line))
{
if (! line)
{
return (0);
}
}
return (-1);
}
/* Function: pop_delete
*
* Purpose: Delete a specified message.
*
* Arguments:
* server Server from which to delete the message.
* message Message to delete.
*
* Return value: 0 on success, non-zero with error in pop_error
* otherwise.
*/
int
pop_delete (server, message)
popserver server;
int message;
{
if (server->in_multi)
{
strcpy (pop_error, "In multi-line query in pop_delete");
return (-1);
}
sprintf (pop_error, "DELE %d", message);
if (sendline (server, pop_error) || getok (server))
return (-1);
return (0);
}
/*
* Function: pop_noop
*
* Purpose: Send a noop command to the server.
*
* Argument:
* server The server to send to.
*
* Return value: 0 on success, non-zero with error in pop_error
* otherwise.
*
* Side effects: Closes connection on error.
*/
int
pop_noop (server)
popserver server;
{
if (server->in_multi)
{
strcpy (pop_error, "In multi-line query in pop_noop");
return (-1);
}
if (sendline (server, "NOOP") || getok (server))
return (-1);
return (0);
}
/*
* Function: pop_last
*
* Purpose: Find out the highest seen message from the server.
*
* Arguments:
* server The server.
*
* Return value: If successful, the highest seen message, which is
* greater than or equal to 0. Otherwise, a negative number with
* the error explained in pop_error.
*
* Side effects: Closes the connection on error.
*/
int
pop_last (server)
popserver server;
{
char *fromserver;
if (server->in_multi)
{
strcpy (pop_error, "In multi-line query in pop_last");
return (-1);
}
if (sendline (server, "LAST"))
return (-1);
if (! (fromserver = pop_getline (server)))
return (-1);
if (! strncmp (fromserver, "-ERR", 4))
{
strncpy (pop_error, fromserver, ERROR_MAX);
return (-1);
}
else if (strncmp (fromserver, "+OK ", 4))
{
strcpy (pop_error, "Unexpected response from server in pop_last");
pop_trash (server);
return (-1);
}
else
{
return (atoi (&fromserver[4]));
}
}
/*
* Function: pop_reset
*
* Purpose: Reset the server to its initial connect state
*
* Arguments:
* server The server.
*
* Return value: 0 for success, non-0 with error in pop_error
* otherwise.
*
* Side effects: Closes the connection on error.
*/
int
pop_reset (server)
popserver server;
{
if (pop_retrieve_flush (server))
{
return (-1);
}
if (sendline (server, "RSET") || getok (server))
return (-1);
return (0);
}
/*
* Function: pop_quit
*
* Purpose: Quit the connection to the server,
*
* Arguments:
* server The server to quit.
*
* Return value: 0 for success, non-zero otherwise with error in
* pop_error.
*
* Side Effects: The popserver passed in is unuseable after this
* function is called, even if an error occurs.
*/
int
pop_quit (server)
popserver server;
{
int ret = 0;
if (server->file >= 0)
{
if (pop_retrieve_flush (server))
{
ret = -1;
}
if (sendline (server, "QUIT") || getok (server))
{
ret = -1;
}
close (server->file);
}
if (server->buffer)
free (server->buffer);
free (server);
return (ret);
}
/*
* Function: socket_connection
*
* Purpose: Opens the network connection with the mail host, without
* doing any sort of I/O with it or anything.
*
* Arguments:
* host The host to which to connect.
* flags Option flags.
*
* Return value: A file descriptor indicating the connection, or -1
* indicating failure, in which case an error has been copied
* into pop_error.
*/
static int
socket_connection (char *host, int flags)
{
struct hostent *hostent;
struct sockaddr_in addr;
char found_port = 0;
char *service;
int sock;
KTEXT ticket;
MSG_DAT msg_data;
CREDENTIALS cred;
Key_schedule schedule;
int rem;
int try_count = 0;
do
{
hostent = gethostbyname (host);
try_count++;
if ((! hostent)
&& ((h_errno != TRY_AGAIN) || (try_count == 5)))
{
strcpy (pop_error, "Could not determine POP server's address");
return (-1);
}
} while (! hostent);
memset (&addr, 0, sizeof (addr));
addr.sin_family = AF_INET;
service = (flags & POP_NO_KERBEROS) ? POP_SERVICE : KPOP_SERVICE;
#ifdef HESIOD
if (! (flags & POP_NO_HESIOD))
{
struct servent *servent = hes_getservbyname (service, "tcp");
if (servent)
{
addr.sin_port = servent->s_port;
found_port = 1;
}
}
#endif
if (! found_port)
{
addr.sin_port = k_getportbyname (service, "tcp",
htons((flags & POP_NO_KERBEROS) ?
POP_PORT : KPOP_PORT));
}
#define SOCKET_ERROR "Could not create socket for POP connection: "
sock = socket (PF_INET, SOCK_STREAM, 0);
if (sock < 0)
{
strcpy (pop_error, SOCKET_ERROR);
strncat (pop_error, strerror (errno),
ERROR_MAX - sizeof (SOCKET_ERROR));
return (-1);
}
while (*hostent->h_addr_list)
{
memcpy (&addr.sin_addr, *hostent->h_addr_list, sizeof(addr.sin_addr));
if (! connect (sock, (struct sockaddr *) &addr, sizeof (addr)))
break;
hostent->h_addr_list++;
}
#define CONNECT_ERROR "Could not connect to POP server: "
if (! *hostent->h_addr_list)
{
close (sock);
strcpy (pop_error, CONNECT_ERROR);
strncat (pop_error, strerror (errno),
ERROR_MAX - sizeof (CONNECT_ERROR));
return (-1);
}
#define KRB_ERROR "Kerberos error connecting to POP server: "
if (! (flags & POP_NO_KERBEROS))
{
char *hostname = strdup((char *)hostent->h_name);
ticket = (KTEXT) malloc (sizeof (KTEXT_ST));
rem = krb_sendauth (0L, sock, ticket, "pop", hostname,
krb_realmofhost (hostname),
0UL, &msg_data, &cred, schedule,
(struct sockaddr_in *) 0,
(struct sockaddr_in *) 0,
"KPOPV0.1");
free (ticket);
free (hostname);
if (rem != KSUCCESS)
{
strcpy (pop_error, KRB_ERROR);
strncat (pop_error, krb_get_err_text(rem),
ERROR_MAX - sizeof (KRB_ERROR));
close (sock);
return (-1);
}
}
return (sock);
} /* socket_connection */
/*
* Function: pop_getline
*
* Purpose: Get a line of text from the connection and return a
* pointer to it. The carriage return and linefeed at the end of
* the line are stripped, but periods at the beginnings of lines
* are NOT dealt with in any special way.
*
* Arguments:
* server The server from which to get the line of text.
*
* Returns: A non-null pointer if successful, or a null pointer on any
* error, with an error message copied into pop_error.
*
* Notes: The line returned is overwritten with each call to pop_getline.
*
* Side effects: Closes the connection on error.
*/
static char *
pop_getline (popserver server)
{
#define GETLINE_ERROR "Error reading from server: "
int ret;
int search_offset = 0;
if (server->data)
{
char *cp = find_crlf (server->buffer + server->buffer_index);
if (cp)
{
int found;
int data_used;
found = server->buffer_index;
data_used = (cp + 2) - server->buffer - found;
*cp = '\0'; /* terminate the string to be returned */
server->data -= data_used;
server->buffer_index += data_used;
if (pop_debug)
fprintf (stderr, "<<< %s\n", server->buffer + found);
return (server->buffer + found);
}
else
{
memmove (server->buffer, server->buffer + server->buffer_index,
server->data);
/* Record the fact that we've searched the data already in
the buffer for a CRLF, so that when we search below, we
don't have to search the same data twice. There's a "-
1" here to account for the fact that the last character
of the data we have may be the CR of a CRLF pair, of
which we haven't read the second half yet, so we may have
to search it again when we read more data. */
search_offset = server->data - 1;
server->buffer_index = 0;
}
}
else
{
server->buffer_index = 0;
}
while (1)
{
/* There's a "- 1" here to leave room for the null that we put
at the end of the read data below. We put the null there so
that find_crlf knows where to stop when we call it. */
if (server->data == server->buffer_size - 1)
{
server->buffer_size += GETLINE_INCR;
server->buffer = realloc (server->buffer, server->buffer_size);
if (! server->buffer)
{
strcpy (pop_error, "Out of memory in pop_getline");
pop_trash (server);
return (0);
}
}
ret = read (server->file, server->buffer + server->data,
server->buffer_size - server->data - 1);
if (ret < 0)
{
strcpy (pop_error, GETLINE_ERROR);
strncat (pop_error, strerror (errno),
ERROR_MAX - sizeof (GETLINE_ERROR));
pop_trash (server);
return (0);
}
else if (ret == 0)
{
strcpy (pop_error, "Unexpected EOF from server in pop_getline");
pop_trash (server);
return (0);
}
else
{
char *cp;
server->data += ret;
server->buffer[server->data] = '\0';
cp = find_crlf (server->buffer + search_offset);
if (cp)
{
int data_used = (cp + 2) - server->buffer;
*cp = '\0';
server->data -= data_used;
server->buffer_index = data_used;
if (pop_debug)
fprintf (stderr, "<<< %s\n", server->buffer);
return (server->buffer);
}
search_offset += ret;
}
}
/* NOTREACHED */
}
/*
* Function: sendline
*
* Purpose: Sends a line of text to the POP server. The line of text
* passed into this function should NOT have the carriage return
* and linefeed on the end of it. Periods at beginnings of lines
* will NOT be treated specially by this function.
*
* Arguments:
* server The server to which to send the text.
* line The line of text to send.
*
* Return value: Upon successful completion, a value of 0 will be
* returned. Otherwise, a non-zero value will be returned, and
* an error will be copied into pop_error.
*
* Side effects: Closes the connection on error.
*/
static int
sendline (popserver server, char *line)
{
#define SENDLINE_ERROR "Error writing to POP server: "
int ret;
ret = fullwrite (server->file, line, strlen (line));
if (ret >= 0)
{ /* 0 indicates that a blank line was written */
ret = fullwrite (server->file, "\r\n", 2);
}
if (ret < 0)
{
pop_trash (server);
strcpy (pop_error, SENDLINE_ERROR);
strncat (pop_error, strerror (errno),
ERROR_MAX - sizeof (SENDLINE_ERROR));
return (ret);
}
if (pop_debug)
fprintf (stderr, ">>> %s\n", line);
return (0);
}
/*
* Procedure: fullwrite
*
* Purpose: Just like write, but keeps trying until the entire string
* has been written.
*
* Return value: Same as write. Pop_error is not set.
*/
static int
fullwrite (int fd, char *buf, int nbytes)
{
char *cp;
int ret;
cp = buf;
while ((ret = write (fd, cp, nbytes)) > 0)
{
cp += ret;
nbytes -= ret;
}
return (ret);
}
/*
* Procedure getok
*
* Purpose: Reads a line from the server. If the return indicator is
* positive, return with a zero exit status. If not, return with
* a negative exit status.
*
* Arguments:
* server The server to read from.
*
* Returns: 0 for success, else for failure and puts error in pop_error.
*
* Side effects: On failure, may make the connection unuseable.
*/
static int
getok (popserver server)
{
char *fromline;
if (! (fromline = pop_getline (server)))
{
return (-1);
}
if (! strncmp (fromline, "+OK", 3))
return (0);
else if (! strncmp (fromline, "-ERR", 4))
{
strncpy (pop_error, fromline, ERROR_MAX);
pop_error[ERROR_MAX-1] = '\0';
return (-1);
}
else
{
strcpy (pop_error,
"Unexpected response from server; expecting +OK or -ERR");
pop_trash (server);
return (-1);
}
}
#if 0
/*
* Function: gettermination
*
* Purpose: Gets the next line and verifies that it is a termination
* line (nothing but a dot).
*
* Return value: 0 on success, non-zero with pop_error set on error.
*
* Side effects: Closes the connection on error.
*/
static int
gettermination (server)
popserver server;
{
char *fromserver;
fromserver = pop_getline (server);
if (! fromserver)
return (-1);
if (strcmp (fromserver, "."))
{
strcpy (pop_error,
"Unexpected response from server in gettermination");
pop_trash (server);
return (-1);
}
return (0);
}
#endif
/*
* Function pop_close
*
* Purpose: Close a pop connection, sending a "RSET" command to try to
* preserve any changes that were made and a "QUIT" command to
* try to get the server to quit, but ignoring any responses that
* are received.
*
* Side effects: The server is unuseable after this function returns.
* Changes made to the maildrop since the session was started (or
* since the last pop_reset) may be lost.
*/
void
pop_close (server)
popserver server;
{
pop_trash (server);
free (server);
return;
}
/*
* Function: pop_trash
*
* Purpose: Like pop_close or pop_quit, but doesn't deallocate the
* memory associated with the server. It is legal to call
* pop_close or pop_quit after this function has been called.
*/
static void
pop_trash (popserver server)
{
if (server->file >= 0)
{
sendline (server, "RSET");
sendline (server, "QUIT");
close (server->file);
server->file = -1;
if (server->buffer)
{
free (server->buffer);
server->buffer = 0;
}
}
}
/* Return a pointer to the first CRLF in IN_STRING,
or 0 if it does not contain one. */
static char *
find_crlf (char *in_string)
{
while (1)
{
if (! *in_string)
return (0);
else if (*in_string == '\r')
{
if (*++in_string == '\n')
return (in_string - 1);
}
else
in_string++;
}
/* NOTREACHED */
}