diff options
Diffstat (limited to 'login/utmpd/request.c')
-rw-r--r-- | login/utmpd/request.c | 650 |
1 files changed, 650 insertions, 0 deletions
diff --git a/login/utmpd/request.c b/login/utmpd/request.c new file mode 100644 index 0000000000..0f68b8ae79 --- /dev/null +++ b/login/utmpd/request.c @@ -0,0 +1,650 @@ +/* Copyright (C) 1997 Free Software Foundation, Inc. + This file is part of the GNU C Library. + Contributed by Mark Kettenis <kettenis@phys.uva.nl>, 1997. + + The GNU C Library is free software; you can redistribute it and/or + modify it under the terms of the GNU Library General Public License as + published by the Free Software Foundation; either version 2 of the + License, or (at your option) any later version. + + The GNU C Library 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 + Library General Public License for more details. + + You should have received a copy of the GNU Library General Public + License along with the GNU C Library; see the file COPYING.LIB. If not, + write to the Free Software Foundation, Inc., 59 Temple Place - Suite 330, + Boston, MA 02111-1307, USA. */ + +#include <assert.h> +#include <errno.h> +#include <string.h> +#include <unistd.h> +#include <utmp.h> + +#include "utmpd.h" +#include "utmpd-private.h" + + +/* Prototypes for the local functions. */ +static int process_request (client_connection *connection); +static int send_reply (client_connection *connect, const reply_header *reply); + +static int do_setutent (client_connection *connection); +static int do_getutent (client_connection *connection); +static int do_endutent (client_connection *connection); +static int do_getutline (client_connection *connection); +static int do_getutid (client_connection *connection); +static int do_pututline (client_connection *connection); +static int do_updwtmp (client_connection *connection); + +static int proc_utmp_eq (const struct utmp *entry, const struct utmp *match); +static int internal_getut_r (client_connection *connection, + const struct utmp *id, struct utmp *buffer); + + +/* Read data from the client on CONNECTION. */ +int +read_data (client_connection *connection) +{ + ssize_t nbytes; + + assert (connection); + assert ((connection->read_end - connection->read_ptr) > 0); + + /* Read data. */ + nbytes = read (connection->sock, connection->read_ptr, + connection->read_end - connection->read_ptr); + if (nbytes > 0) + { + size_t total_bytes; + + /* Update read pointer. */ + connection->read_ptr += nbytes; + + /* Check if we have a complete request header. */ + total_bytes = connection->read_ptr - connection->read_base; + if (total_bytes >= sizeof (request_header)) + { + request_header *header; + + /* Check if we have a complete request. */ + header = (request_header *)connection->read_base; + if (total_bytes >= header->size) + { + /* Process the request. */ + if (process_request (connection) < 0) + return -1; + + /* Adjust read pointer, and flush buffer. */ + connection->read_ptr -= header->size; + memmove (connection->read_base, + connection->read_base + header->size, + connection->read_ptr - connection->read_base); + } + } + + return 0; + } + + if (nbytes < 0) + error (0, errno, "cannot read from client"); + + return -1; +} + + +/* Write data to the client on CONNECTION. */ +int +write_data (client_connection *connection) +{ + ssize_t nbytes; + + assert (connection); + assert ((connection->write_ptr - connection->write_base) > 0); + + /* Write data. */ + nbytes = write (connection->sock, connection->write_base, + connection->write_ptr - connection->write_base); + if (nbytes > 0) + { + /* Adjust write pointer and flush buffer. */ + connection->write_ptr -= nbytes; + memmove (connection->write_base, connection->write_base + nbytes, + connection->write_ptr - connection->write_base); + + return 0; + } + + if (nbytes < 0) + error (0, errno, "cannot write to client"); + + return -1; +} + + +/* Process the request received on CONNECTION. Returns 0 if + successful, -1 if not. */ +static int +process_request (client_connection *connection) +{ + request_header *header; + + assert (connection); + assert (connection->read_base); + + header = (request_header *)connection->read_base; + if (header->version != UTMPD_VERSION) + { + warning (EINVAL, "invalid protocol version"); + return -1; + } + + switch (header->type) + { + case UTMPD_REQ_SETUTENT: return do_setutent (connection); + case UTMPD_REQ_GETUTENT: return do_getutent (connection); + case UTMPD_REQ_ENDUTENT: return do_endutent (connection); + case UTMPD_REQ_GETUTLINE: return do_getutline (connection); + case UTMPD_REQ_GETUTID: return do_getutid (connection); + case UTMPD_REQ_PUTUTLINE: return do_pututline (connection); + case UTMPD_REQ_UPDWTMP: return do_updwtmp (connection); + default: + warning (EINVAL, "invalid request type"); + return -1; + } +} + + +/* Send the reply specified by HEADER to the client on CONNECTION. + Returns 0 if successful, -1 if not. */ +static int +send_reply (client_connection *connection, const reply_header *reply) +{ + /* Check if the reply fits in the buffer. */ + if ((size_t) (connection->write_end - connection->write_ptr) < reply->size) + { + error (0, 0, "buffer overflow"); + return -1; + } + + /* Copy reply to buffer, and adjust write pointer. */ + memcpy (connection->write_ptr, reply, reply->size); + connection->write_ptr += reply->size; + + return 0; +} + + +static int +do_setutent (client_connection *connection) +{ + setutent_request *request; + setutent_reply reply; + + request = (setutent_request *)connection->read_base; + if (request->header.size != sizeof (setutent_request)) + { + warning (EINVAL, "invalid request size"); + return -1; + } + + /* Initialize reply. */ + reply.header.version = UTMPD_VERSION; + reply.header.size = sizeof (setutent_reply); + reply.header.type = UTMPD_REQ_SETUTENT; + + /* Select database. */ + if (!strncmp (request->file, _PATH_UTMP, sizeof request->file)) + connection->database = utmp_db; + else + { + errno = EINVAL; + goto return_error; + } + + /* Initialize position pointer. */ + connection->position = 0; + +#if _HAVE_UT_TYPE - 0 + /* Make sure the entry won't match. */ + connection->last_entry.ut_type = -1; +#endif + + reply.errnum = 0; + reply.result = 0; + return send_reply (connection, &reply.header); + +return_error: + reply.errnum = errno; + reply.result = -1; + return send_reply (connection, &reply.header); +} + + +static int +do_getutent (client_connection *connection) +{ + getutent_request *request; + getutent_reply reply; + + request = (getutent_request *)connection->read_base; + if (request->header.size != sizeof (getutent_request)) + { + warning (EINVAL, "invalid request size"); + return -1; + } + + /* Initialize reply. */ + reply.header.version = UTMPD_VERSION; + reply.header.size = sizeof (getutent_reply); + reply.header.type = UTMPD_REQ_GETUTENT; + + if (connection->database == NULL || connection->position == -1) + { + errno = ESRCH; + goto return_error; + } + + /* Make sure we're in synch with the ordinary file. */ + if (synchronize_database (connection->database) < 0) + { + errno = ESRCH; + goto return_error; + } + + /* Read the next entry from the database. */ + if (read_entry (connection->database, connection->position, + &connection->last_entry) < 0) + { + connection->position = -1; + errno = ESRCH; + goto return_error; + } + + /* Update position pointer. */ + connection->position++; + + memcpy (&reply.entry, &connection->last_entry, sizeof (struct utmp)); + reply.errnum = 0; + reply.result = 0; + return send_reply (connection, (reply_header *)&reply); + +return_error: + memset (&reply.entry, 0, sizeof (struct utmp)); + reply.errnum = errno; + reply.result = -1; + return send_reply (connection, &reply.header); +} + + +static int +do_endutent (client_connection *connection) +{ + endutent_request *request; + endutent_reply reply; + + request = (endutent_request *)connection->read_base; + if (request->header.size != sizeof (endutent_request)) + { + warning (EINVAL, "invalid request size"); + return -1; + } + + /* Deselect database. */ + connection->database = NULL; + + /* Formulate reply. */ + reply.header.version = UTMPD_VERSION; + reply.header.size = sizeof (endutent_reply); + reply.header.type = UTMPD_REQ_ENDUTENT; + reply.errnum = 0; + reply.result = 0; + + return send_reply (connection, &reply.header); +} + + +static int +do_getutline (client_connection *connection) +{ + getutline_request *request; + getutline_reply reply; + + request = (getutline_request *)connection->read_base; + if (request->header.size != sizeof (getutline_request)) + { + warning (EINVAL, "invalid request size"); + return -1; + } + + /* Initialize reply. */ + reply.header.version = UTMPD_VERSION; + reply.header.size = sizeof (getutline_reply); + reply.header.type = UTMPD_REQ_GETUTLINE; + + if (connection->database == NULL || connection->position == -1) + { + errno = ESRCH; + goto return_error; + } + + /* Make sure we're in synch with the ordinary file. */ + if (synchronize_database (connection->database) < 0) + { + errno = ESRCH; + goto return_error; + } + + while (1) + { + /* Read the next entry. */ + if (read_entry (connection->database, connection->position, + &connection->last_entry) < 0) + { + connection->position = -1; + errno = ESRCH; + goto return_error; + } + connection->position++; + + /* Stop if we found a user or login entry. */ + if ( +#if _HAVE_UT_TYPE - 0 + (connection->last_entry.ut_type == USER_PROCESS + || connection->last_entry.ut_type == LOGIN_PROCESS) + && +#endif + !strncmp (request->line.ut_line, connection->last_entry.ut_line, + sizeof request->line.ut_line)) + break; + } + + memcpy (&reply.entry, &connection->last_entry, sizeof (struct utmp)); + reply.errnum = 0; + reply.result = 0; + return send_reply (connection, &reply.header); + +return_error: + memset (&reply.entry, 0, sizeof (struct utmp)); + reply.errnum = errno; + reply.result = -1; + return send_reply (connection, &reply.header); +} + + +static int +do_getutid (client_connection *connection) +{ + getutid_request *request; + getutid_reply reply; + + request = (getutid_request *)connection->read_base; + if (request->header.size != sizeof (getutid_request)) + { + warning (EINVAL, "invalid request size"); + return -1; + } + + /* Initialize reply. */ + reply.header.version = UTMPD_VERSION; + reply.header.size = sizeof (getutid_reply); + reply.header.type = UTMPD_REQ_GETUTID; + + if (connection->database == NULL || connection->position == -1) + { + errno = ESRCH; + goto return_error; + } + + /* Make sure we're in synch with the ordinary file. */ + if (synchronize_database (connection->database) < 0) + { + errno = ESRCH; + goto return_error; + } + + if (internal_getut_r (connection, &request->id, + &connection->last_entry) < 0) + { + errno = ESRCH; + goto return_error; + } + + reply.errnum = 0; + reply.result = 0; + memcpy (&reply.entry, &connection->last_entry, sizeof (struct utmp)); + return send_reply (connection, &reply.header); + +return_error: + memset (&reply.entry, 0, sizeof (struct utmp)); + reply.errnum = errno; + reply.result = -1; + return send_reply (connection, &reply.header); +} + + +static int +do_pututline (client_connection *connection) +{ + pututline_request *request; + pututline_reply reply; + struct utmp buffer; + int found; + + request = (pututline_request *)connection->read_base; + if (request->header.size != sizeof (pututline_request)) + { + warning (EINVAL, "invalid request size"); + return -1; + } + + /* Initialize reply. */ + reply.header.version = UTMPD_VERSION; + reply.header.size = sizeof (pututline_reply); + reply.header.type = UTMPD_REQ_PUTUTLINE; + + if (!(connection->access & W_OK)) + { + errno = EPERM; + goto return_error; + } + + if (connection->database == NULL || connection->position == -1) + { + errno = ESRCH; + goto return_error; + } + + /* Make sure we're in synch with the ordinary file. */ + if (synchronize_database (connection->database) < 0) + { + errno = ESRCH; + goto return_error; + } + + /* Find the correct place to insert the data. */ + if (connection->position > 0 + && ( +#if _HAVE_UT_TYPE - 0 + (connection->last_entry.ut_type == request->utmp.ut_type + && (connection->last_entry.ut_type == RUN_LVL + || connection->last_entry.ut_type == BOOT_TIME + || connection->last_entry.ut_type == OLD_TIME + || connection->last_entry.ut_type == NEW_TIME)) + || +#endif + proc_utmp_eq (&connection->last_entry, &request->utmp))) + found = 1; + else + found = internal_getut_r (connection, &request->utmp, &buffer); + + if (found < 0) + { + /* We append the next entry. */ + connection->position = + append_entry (connection->database, &request->utmp); + if (connection->position < 0) + goto return_error; + } + else + { + /* We replace the just read entry. */ + connection->position--; + if (write_entry (connection->database, connection->position, + &request->utmp) < 0) + goto return_error; + } + + /* Write the entry to the compatibility file. */ + write_old_entry (connection->database, connection->position, &request->utmp); + + /* Update position pointer. */ + connection->position++; + + reply.errnum = 0; + reply.result = 0; + return send_reply (connection, &reply.header); + +return_error: + reply.errnum = errno; + reply.result = -1; + return send_reply (connection, &reply.header); +} + + +static int +do_updwtmp (client_connection *connection) +{ + updwtmp_request *request; + updwtmp_reply reply; + utmp_database *database; + + request = (updwtmp_request *)connection->read_base; + if (request->header.size != sizeof (updwtmp_request)) + { + warning (EINVAL, "invalid request size"); + return -1; + } + + /* Initialize reply. */ + reply.header.version = UTMPD_VERSION; + reply.header.size = sizeof (updwtmp_reply); + reply.header.type = UTMPD_REQ_UPDWTMP; + + if (!(connection->access & W_OK)) + { + errno = EPERM; + goto return_error; + } + + /* Select database. */ + if (!strncmp (request->file, _PATH_UTMP, sizeof request->file)) + database = utmp_db; + else + { + errno = EINVAL; + goto return_error; + } + + /* Make sure we're in synch with the ordinary file. */ + if (synchronize_database (database) < 0) + { + errno = ESRCH; + goto return_error; + } + + /* Append the entry. */ + if (append_entry (database, &request->utmp) < 0) + goto return_error; + + reply.errnum = 0; + reply.result = 0; + return send_reply (connection, &reply.header); + +return_error: + reply.errnum = errno; + reply.result = -1; + return send_reply (connection, &reply.header); +} + + +/* This function is identical to the one in login/utmp_file.c. */ +static int +proc_utmp_eq (const struct utmp *entry, const struct utmp *match) +{ + return + ( +#if _HAVE_UT_TYPE - 0 + (entry->ut_type == INIT_PROCESS + || entry->ut_type == LOGIN_PROCESS + || entry->ut_type == USER_PROCESS + || entry->ut_type == DEAD_PROCESS) + && + (match->ut_type == INIT_PROCESS + || match->ut_type == LOGIN_PROCESS + || match->ut_type == USER_PROCESS + || match->ut_type == DEAD_PROCESS) + && +#endif +#if _HAVE_UT_ID - 0 + strncmp (entry->ut_id, match->ut_id, sizeof match->ut_id) == 0 +#else + strncmp (entry->ut_line, match->ut_line, sizeof match->ut_line) == 0 +#endif + ); +} + + +/* This function is derived from the one in login/utmp_file.c. */ +static int +internal_getut_r (client_connection *connection, + const struct utmp *id, struct utmp *buffer) +{ +#if _HAVE_UT_TYPE - 0 + if (id->ut_type == RUN_LVL || id->ut_type == BOOT_TIME + || id->ut_type == OLD_TIME || id->ut_type == NEW_TIME) + { + /* Search for next entry with type RUN_LVL, BOOT_TIME, + OLD_TIME, or NEW_TIME. */ + + while (1) + { + /* Read the next entry. */ + if (read_entry (connection->database, connection->position, + buffer) < 0) + { + connection->position = -1; + return -1; + } + connection->position++; + + if (id->ut_type == buffer->ut_type) + break; + } + } + else +#endif /* _HAVE_UT_TYPE */ + { + /* Search for the next entry with the specified ID and with type + INIT_PROCESS, LOGIN_PROCESS, USER_PROCESS, or DEAD_PROCESS. */ + + while (1) + { + /* Read the next entry. */ + if (read_entry (connection->database, connection->position, + buffer) < 0) + { + connection->position = -1; + return -1; + } + connection->position++; + + if (proc_utmp_eq (buffer, id)) + break; + } + } + + return 0; +} |