2 * Copyright (C) 2005-2009 Andre Noll <maan@systemlinux.org>
4 * Licensed under the GPL v2. For licencing details see COPYING.
7 /** \file net.c Networking-related helper functions. */
10 * Since glibc 2.8, the _GNU_SOURCE feature test macro must be defined in order
11 * to obtain the definition of the ucred structure.
17 /* At least NetBSD needs these. */
25 #define AI_ADDRCONFIG 0
30 #include <openssl/rc4.h>
41 * Parse and validate IPv4 address/netmask string.
43 * \param cidr Address in CIDR notation
44 * \param addr Copy of the IPv4 address part of \a cidr
45 * \param addrlen Size of \a addr in bytes
46 * \param netmask Value of the netmask part in \a cidr or the
47 * default of 32 if not specified.
49 * \return Pointer to \a addr if succesful, NULL on error.
52 char *parse_cidr(const char *cidr
,
53 char *addr
, ssize_t addrlen
,
57 char *c
= addr
, *end
= c
+ (addrlen
- 1);
61 if (cidr
== NULL
|| addrlen
< 1)
64 for (o
= cidr
; (*c
= *o
== '/'? '\0' : *o
); c
++, o
++)
69 if (para_atoi32(++o
, netmask
) < 0 ||
70 *netmask
< 0 || *netmask
> 0x20)
73 if (is_valid_ipv4_address(addr
))
82 * Match string as a candidate IPv4 address.
84 * \param address The string to match.
85 * \return True if \a address has "dot-quad" format.
87 static bool is_v4_dot_quad(const char *address
)
92 assert(para_regcomp(&r
, "^([0-9]+\\.){3}[0-9]+$",
93 REG_EXTENDED
| REG_NOSUB
) >= 0);
94 result
= regexec(&r
, address
, 0, NULL
, 0) == 0;
100 * Perform basic syntax checking on the host-part of an URL:
102 * - Since ':' is invalid in IPv4 addresses and DNS names, the
103 * presence of ':' causes interpretation as IPv6 address;
104 * - next the first-match-wins algorithm from RFC 3986 is applied;
105 * - else the string is considered as DNS name, to be resolved later.
107 * \param host The host string to check.
108 * \return True if \a host passes the syntax checks.
110 * \sa RFC 3986, 3.2.2; RFC 1123, 2.1; RFC 1034, 3.5
112 static bool host_string_ok(const char *host
)
114 if (host
== NULL
|| *host
== '\0')
116 if (strchr(host
, ':') != NULL
)
117 return is_valid_ipv6_address(host
);
118 if (is_v4_dot_quad(host
))
119 return is_valid_ipv4_address(host
);
124 * Parse and validate URL string.
126 * The URL syntax is loosely based on RFC 3986, supporting one of
127 * - "["host"]"[:port] for native IPv6 addresses and
128 * - host[:port] for IPv4 hostnames and DNS names.
130 * Native IPv6 addresses must be enclosed in square brackets, since
131 * otherwise there is an ambiguity with the port separator `:'.
132 * The 'port' part is always considered to be a number; if absent,
133 * it is set to -1, to indicate that a default port is to be used.
135 * The following are valid examples:
143 * \param url The URL string to take apart.
144 * \param host To return the copied host part of \a url.
145 * \param hostlen The maximum length of \a host.
146 * \param port To return the port number (if any) of \a url.
148 * \return Pointer to \a host, or NULL if failed.
149 * If NULL is returned, \a host and \a portnum are undefined. If no
150 * port number was present in \a url, \a portnum is set to -1.
152 * \sa RFC 3986, 3.2.2/3.2.3
154 char *parse_url(const char *url
,
155 char *host
, ssize_t hostlen
,
159 char *c
= host
, *end
= c
+ (hostlen
- 1);
163 if (o
== NULL
|| hostlen
< 1)
167 for (++o
; (*c
= *o
== ']' ? '\0' : *o
); c
++, o
++)
171 if (*o
++ != ']' || (*o
!= '\0' && *o
!= ':'))
174 for (; (*c
= *o
== ':'? '\0' : *o
); c
++, o
++)
180 if (para_atoi32(++o
, port
) < 0 ||
181 *port
< 0 || *port
> 0xffff)
184 if (host_string_ok(host
))
192 * Stringify port number, resolve into service name where defined.
193 * \param port 2-byte port number, in host-byte-order.
194 * \param transport Transport protocol name (e.g. "udp", "tcp"), or NULL.
195 * \return Pointer to static result buffer.
197 * \sa getservent(3), services(5), nsswitch.conf(5)
199 const char *stringify_port(int port
, const char *transport
)
201 static char service
[NI_MAXSERV
];
203 if (port
< 0 || port
> 0xFFFF) {
204 snprintf(service
, sizeof(service
), "undefined (%d)", port
);
206 struct servent
*se
= getservbyport(htons(port
), transport
);
209 snprintf(service
, sizeof(service
), "%u", port
);
211 snprintf(service
, sizeof(service
), "%s", se
->s_name
);
217 * Determine the socket type for a given layer-4 protocol.
219 * \param l4type The symbolic name of the transport-layer protocol.
221 * \sa ip(7), socket(2)
223 static inline int sock_type(const unsigned l4type
)
226 case IPPROTO_UDP
: return SOCK_DGRAM
;
227 case IPPROTO_TCP
: return SOCK_STREAM
;
228 case IPPROTO_DCCP
: return SOCK_DCCP
;
230 return -1; /* not supported here */
234 * Pretty-print transport-layer name.
236 static const char *layer4_name(const unsigned l4type
)
239 case IPPROTO_UDP
: return "UDP";
240 case IPPROTO_TCP
: return "TCP";
241 case IPPROTO_DCCP
: return "DCCP";
243 return "UNKNOWN PROTOCOL";
247 * Flowopts: Transport-layer independent encapsulation of socket options.
249 * These collect individual socket options into a queue, which is disposed of
250 * directly after makesock(). The 'pre_conn_opt' structure is for internal use
251 * only and should not be visible elsewhere.
253 * \sa setsockopt(2), makesock()
255 struct pre_conn_opt
{
256 int sock_level
; /**< Second argument to setsockopt() */
257 int sock_option
; /**< Third argument to setsockopt() */
258 char *opt_name
; /**< Stringified \a sock_option */
259 void *opt_val
; /**< Fourth argument to setsockopt() */
260 socklen_t opt_len
; /**< Fifth argument to setsockopt() */
262 struct list_head node
; /**< FIFO, as sockopt order matters. */
265 /** FIFO list of pre-connection socket options to be set */
267 struct list_head sockopts
;
270 struct flowopts
*flowopt_new(void)
272 struct flowopts
*new = para_malloc(sizeof(*new));
274 INIT_LIST_HEAD(&new->sockopts
);
279 * Append new socket option to flowopt queue.
281 * \param fo The flowopt queue to append to.
282 * \param lev Level at which \a opt resides.
283 * \param opt New option to add.
284 * \param name Stringified name of \a opt.
285 * \param val The value to set \a opt to.
286 * \param len Length of \a val.
290 void flowopt_add(struct flowopts
*fo
, int lev
, int opt
,
291 char *name
, const void *val
, int len
)
293 struct pre_conn_opt
*new = para_malloc(sizeof(*new));
295 new->sock_option
= opt
;
296 new->sock_level
= lev
;
297 new->opt_name
= para_strdup(name
);
303 new->opt_val
= para_malloc(len
);
305 memcpy(new->opt_val
, val
, len
);
308 list_add_tail(&new->node
, &fo
->sockopts
);
311 void flowopt_add_bool(struct flowopts
*fo
, int lev
, int opt
,
312 char *optname
, bool on_or_off
)
314 int on
= on_or_off
; /* kernel takes 'int' */
316 flowopt_add(fo
, lev
, opt
, optname
, &on
, sizeof(on
));
319 /** Set the entire bunch of pre-connection options at once. */
320 static void flowopt_setopts(int sockfd
, struct flowopts
*fo
)
322 struct pre_conn_opt
*pc
;
327 list_for_each_entry(pc
, &fo
->sockopts
, node
)
328 if (setsockopt(sockfd
, pc
->sock_level
, pc
->sock_option
,
329 pc
->opt_val
, pc
->opt_len
) < 0) {
330 PARA_EMERG_LOG("Can not set %s socket option: %s",
331 pc
->opt_name
, strerror(errno
));
336 static void flowopt_cleanup(struct flowopts
*fo
)
338 struct pre_conn_opt
*cur
, *next
;
343 list_for_each_entry_safe(cur
, next
, &fo
->sockopts
, node
) {
352 * Resolve IPv4/IPv6 address and create a ready-to-use active or passive socket.
354 * \param l4type The layer-4 type (\p IPPROTO_xxx).
355 * \param passive Whether this is a passive (1) or active (0) socket.
356 * \param host Remote or local hostname or IPv/6 address string.
357 * \param port_number Decimal port number.
358 * \param fo Socket options to be set before making the connection.
360 * This creates a ready-made IPv4/v6 socket structure after looking up the
361 * necessary parameters. The interpretation of \a host depends on the value of
363 * - on a passive socket host is interpreted as an interface IPv4/6 address
364 * (can be left NULL);
365 * - on an active socket, \a host is the peer DNS name or IPv4/6 address
367 * - \a port_number is in either case the numeric port number (not service
370 * Furthermore, bind(2) is called on passive sockets, and connect(2) on active
371 * sockets. The algorithm tries all possible address combinations until it
372 * succeeds. If \a fo is supplied, options are set and cleanup is performed.
374 * \return This function returns 1 on success and \a -E_ADDRESS_LOOKUP when no
375 * matching connection could be set up (with details in the error log).
377 * \sa ipv6(7), getaddrinfo(3), bind(2), connect(2).
379 int makesock(unsigned l4type
, bool passive
,
380 const char *host
, uint16_t port_number
,
383 struct addrinfo
*local
= NULL
, *src
,
384 *remote
= NULL
, *dst
, hints
;
385 unsigned int l3type
= AF_UNSPEC
;
386 int rc
, on
= 1, sockfd
= -1,
387 socktype
= sock_type(l4type
);
388 char port
[6]; /* port number has at most 5 digits */
390 sprintf(port
, "%u", port_number
);
391 /* Set up address hint structure */
392 memset(&hints
, 0, sizeof(hints
));
393 hints
.ai_family
= l3type
;
394 hints
.ai_socktype
= socktype
;
396 * getaddrinfo does not support SOCK_DCCP, so for the sake of lookup
397 * (and only then) pretend to be UDP.
399 if (l4type
== IPPROTO_DCCP
)
400 hints
.ai_socktype
= SOCK_DGRAM
;
402 /* only use addresses available on the host */
403 hints
.ai_flags
= AI_ADDRCONFIG
;
404 if (l3type
== AF_INET6
)
405 /* use v4-mapped-v6 if no v6 addresses found */
406 hints
.ai_flags
|= AI_V4MAPPED
| AI_ALL
;
408 if (passive
&& host
== NULL
)
409 hints
.ai_flags
|= AI_PASSIVE
;
411 /* Obtain local/remote address information */
412 if ((rc
= getaddrinfo(host
, port
, &hints
, passive
? &local
: &remote
))) {
413 PARA_ERROR_LOG("can not resolve %s address %s#%s: %s.\n",
415 host
? host
: (passive
? "[loopback]" : "[localhost]"),
416 port
, gai_strerror(rc
));
417 return -E_ADDRESS_LOOKUP
;
420 /* Iterate over all src/dst combination, exhausting dst first */
421 for (src
= local
, dst
= remote
; src
!= NULL
|| dst
!= NULL
; /* no op */ ) {
422 if (src
&& dst
&& src
->ai_family
== AF_INET
423 && dst
->ai_family
== AF_INET6
)
424 goto get_next_dst
; /* v4 -> v6 is not possible */
426 sockfd
= socket(src
? src
->ai_family
: dst
->ai_family
,
432 * Reuse the address on passive sockets to avoid failure on
433 * restart (protocols using listen()) and when creating
434 * multiple listener instances (UDP multicast).
436 if (passive
&& setsockopt(sockfd
, SOL_SOCKET
, SO_REUSEADDR
,
437 &on
, sizeof(on
)) == -1) {
439 PARA_ERROR_LOG("can not set SO_REUSEADDR: %s\n",
441 return -ERRNO_TO_PARA_ERROR(rc
);
443 flowopt_setopts(sockfd
, fo
);
446 if (bind(sockfd
, src
->ai_addr
, src
->ai_addrlen
) < 0) {
450 if (!dst
) /* bind-only completed successfully */
454 if (dst
&& connect(sockfd
, dst
->ai_addr
, dst
->ai_addrlen
) == 0)
455 break; /* connection completed successfully */
458 if (dst
&& (dst
= dst
->ai_next
))
461 if (src
&& (src
= src
->ai_next
)) /* restart inner loop */
467 freeaddrinfo(remote
);
470 if (src
== NULL
&& dst
== NULL
) {
472 PARA_ERROR_LOG("can not create %s socket %s#%s.\n",
473 layer4_name(l4type
), host
? host
: (passive
?
474 "[loopback]" : "[localhost]"), port
);
475 return -ERRNO_TO_PARA_ERROR(rc
);
481 * Create a passive / listening socket.
483 * \param l4type The transport-layer type (\p IPPROTO_xxx).
484 * \param port The decimal port number to listen on.
485 * \param fo Flowopts (if any) to set before starting to listen.
487 * \return Positive integer (socket descriptor) on success, negative value
490 * \sa makesock(), ip(7), ipv6(7), bind(2), listen(2).
492 int para_listen(unsigned l4type
, uint16_t port
, struct flowopts
*fo
)
494 int ret
, fd
= makesock(l4type
, 1, NULL
, port
, fo
);
497 ret
= listen(fd
, BACKLOG
);
501 return -ERRNO_TO_PARA_ERROR(ret
);
503 PARA_INFO_LOG("listening on %s port %u, fd %d\n",
504 layer4_name(l4type
), port
, fd
);
510 * Determine IPv4/v6 socket address length.
511 * \param sa Container of IPv4 or IPv6 address.
512 * \return Address-family dependent address length.
514 static socklen_t
salen(const struct sockaddr
*sa
)
516 assert(sa
->sa_family
== AF_INET
|| sa
->sa_family
== AF_INET6
);
518 return sa
->sa_family
== AF_INET6
519 ? sizeof(struct sockaddr_in6
)
520 : sizeof(struct sockaddr_in
);
524 * Process IPv4/v6 address, turn v6-mapped-v4 address into normal IPv4 address.
525 * \param ss Container of IPv4/6 address.
526 * \return Pointer to normalized address (may be static storage).
530 static const struct sockaddr
*
531 normalize_ip_address(const struct sockaddr_storage
*ss
)
533 const struct sockaddr_in6
*ia6
= (const struct sockaddr_in6
*)ss
;
535 assert(ss
->ss_family
== AF_INET
|| ss
->ss_family
== AF_INET6
);
537 if (ss
->ss_family
== AF_INET6
&& IN6_IS_ADDR_V4MAPPED(&ia6
->sin6_addr
)) {
538 static struct sockaddr_in ia
;
540 ia
.sin_family
= AF_INET
;
541 ia
.sin_port
= ia6
->sin6_port
;
542 memcpy(&ia
.sin_addr
.s_addr
, &(ia6
->sin6_addr
.s6_addr
[12]), 4);
543 return (const struct sockaddr
*)&ia
;
545 return (const struct sockaddr
*)ss
;
549 * Print numeric host and port number (beware - uses static char).
551 * \param sa The IPv4/IPv6 socket address to use.
553 * \sa getnameinfo(3), services(5), nsswitch.conf(5)
555 static char *host_and_port(const struct sockaddr_storage
*ss
)
557 const struct sockaddr
*sa
= normalize_ip_address(ss
);
558 char hbuf
[NI_MAXHOST
], sbuf
[NI_MAXSERV
];
559 static char output
[sizeof(hbuf
) + sizeof(sbuf
) + 2];
562 ret
= getnameinfo(sa
, salen(sa
),
567 snprintf(output
, sizeof(output
), "%s#%s", hbuf
, sbuf
);
569 snprintf(output
, sizeof(output
), "(unknown)");
570 PARA_WARNING_LOG("hostname lookup error (%s).\n",
577 * Look up the local or remote side of a connected socket structure.
579 * \param fd The socket descriptor of the connected socket.
580 * \param getname Either \p getsockname() for local, or \p getpeername() for
583 * \return A static character string identifying hostname and port of the
586 * \sa getsockname(2), getpeername(2).
588 static char *__get_sock_name(int fd
, int (*getname
)(int, struct sockaddr
*,
591 struct sockaddr_storage ss
;
592 socklen_t sslen
= sizeof(ss
);
594 if (getname(fd
, (struct sockaddr
*)&ss
, &sslen
) < 0) {
595 static char *dont_know
= "(don't know)";
596 PARA_ERROR_LOG("can not determine address from fd %d: %s\n",
597 fd
, strerror(errno
));
600 return host_and_port(&ss
);
604 * Look up the local side of a connected socket structure.
606 * \param sockfd The file descriptor of the socket.
608 * \return A pointer to a static buffer containing hostname an port. This
609 * buffer must not be freed by the caller.
613 char *local_name(int sockfd
)
615 return __get_sock_name(sockfd
, getsockname
);
619 * Look up the remote side of a connected socket structure.
621 * \param sockfd The file descriptor of the socket.
623 * \return Analogous to the return value of \ref local_name() but for the
628 char *remote_name(int sockfd
)
630 return __get_sock_name(sockfd
, getpeername
);
634 * Extract IPv4 or IPv6-mapped-IPv4 address from sockaddr_storage.
635 * \param ss Container of IPv4/6 address
636 * \return Extracted IPv4 address (different from 0) or 0 if unsuccessful.
640 struct in_addr
extract_v4_addr(const struct sockaddr_storage
*ss
)
642 struct in_addr ia
= {.s_addr
= 0};
643 const struct sockaddr
*sa
= normalize_ip_address(ss
);
645 if (sa
->sa_family
== AF_INET
)
646 ia
= ((struct sockaddr_in
*)sa
)->sin_addr
;
651 * Send a binary buffer.
653 * \param fd The file descriptor.
654 * \param buf The buffer to be sent.
655 * \param len The length of \a buf.
657 * Send out the buffer and try to resend the remaining part in case of short
662 int send_bin_buffer(int fd
, const char *buf
, size_t len
)
665 PARA_CRIT_LOG("len == 0\n");
666 return write_all(fd
, buf
, &len
);
670 * Send a \p NULL-terminated buffer.
672 * \param fd The file descriptor.
673 * \param buf The null-terminated buffer to be send.
675 * This is equivalent to send_bin_buffer(fd, buf, strlen(buf)).
679 int send_buffer(int fd
, const char *buf
)
681 return send_bin_buffer(fd
, buf
, strlen(buf
));
685 * Send a buffer given by a format string.
687 * \param fd The file descriptor.
688 * \param fmt A format string.
692 __printf_2_3
int send_va_buffer(int fd
, const char *fmt
, ...)
697 PARA_VSPRINTF(fmt
, msg
);
698 ret
= send_buffer(fd
, msg
);
704 * Receive data from a file descriptor.
706 * \param fd The file descriptor.
707 * \param buf The buffer to write the data to.
708 * \param size The size of \a buf.
710 * Receive at most \a size bytes from file descriptor \a fd.
712 * \return The number of bytes received on success, negative on errors, zero if
713 * the peer has performed an orderly shutdown.
717 __must_check
int recv_bin_buffer(int fd
, char *buf
, size_t size
)
721 n
= recv(fd
, buf
, size
, 0);
723 return -ERRNO_TO_PARA_ERROR(errno
);
728 * Receive and write terminating NULL byte.
730 * \param fd The file descriptor.
731 * \param buf The buffer to write the data to.
732 * \param size The size of \a buf.
734 * Read at most \a size - 1 bytes from file descriptor \a fd and
735 * write a NULL byte at the end of the received data.
737 * \return The return value of the underlying call to \a recv_bin_buffer().
739 * \sa recv_bin_buffer()
741 int recv_buffer(int fd
, char *buf
, size_t size
)
746 n
= recv_bin_buffer(fd
, buf
, size
- 1);
755 * Wrapper around the accept system call.
757 * \param fd The listening socket.
758 * \param addr Structure which is filled in with the address of the peer socket.
759 * \param size Should contain the size of the structure pointed to by \a addr.
761 * Accept incoming connections on \a addr. Retry if interrupted.
763 * \return The new file descriptor on success, negative on errors.
767 int para_accept(int fd
, void *addr
, socklen_t size
)
772 new_fd
= accept(fd
, (struct sockaddr
*) addr
, &size
);
773 while (new_fd
< 0 && errno
== EINTR
);
774 return new_fd
< 0? -ERRNO_TO_PARA_ERROR(errno
) : new_fd
;
778 * Probe the list of DCCP CCIDs supported locally by the host.
779 * \param ccids Array to be filled in.
780 * \param nccids Length of \a ccids.
781 * \return Pointer to \a ccids, NULL on failure.
783 * NB: This feature is only available on Linux > 2.6.30; on older kernels
784 * ENOPROTOOPT ("Protocol not available") will be returned.
786 const uint8_t *dccp_available_ccids(uint8_t *ccids
, uint8_t *nccids
)
788 int fd
= makesock(IPPROTO_DCCP
, 1, NULL
, 0, NULL
);
793 if (getsockopt(fd
, SOL_DCCP
, DCCP_SOCKOPT_AVAILABLE_CCIDS
,
794 ccids
, (socklen_t
*)nccids
) < 0) {
795 PARA_ERROR_LOG("No DCCP_SOCKOPT_AVAILABLE_CCIDS: %s\n",
801 return *nccids
? ccids
: NULL
;
805 * Prepare a structure for \p AF_UNIX socket addresses.
807 * \param u Pointer to the struct to be prepared.
808 * \param name The socket pathname.
810 * This just copies \a name to the sun_path component of \a u.
812 * \return Positive on success, \p -E_NAME_TOO_LONG if \a name is longer
813 * than \p UNIX_PATH_MAX.
815 static int init_unix_addr(struct sockaddr_un
*u
, const char *name
)
817 if (strlen(name
) >= UNIX_PATH_MAX
)
818 return -E_NAME_TOO_LONG
;
819 memset(u
->sun_path
, 0, UNIX_PATH_MAX
);
820 u
->sun_family
= PF_UNIX
;
821 strcpy(u
->sun_path
, name
);
826 * Prepare, create, and bind a socket for local communication.
828 * \param name The socket pathname.
829 * \param unix_addr Pointer to the \p AF_UNIX socket structure.
830 * \param mode The desired mode of the socket.
832 * This function creates a local socket for sequenced, reliable,
833 * two-way, connection-based byte streams.
835 * \return The file descriptor, on success, negative on errors.
841 int create_local_socket(const char *name
, struct sockaddr_un
*unix_addr
,
846 ret
= init_unix_addr(unix_addr
, name
);
849 ret
= socket(PF_UNIX
, SOCK_STREAM
, 0);
851 return -ERRNO_TO_PARA_ERROR(errno
);
853 ret
= bind(fd
, (struct sockaddr
*) unix_addr
, UNIX_PATH_MAX
);
855 ret
= -ERRNO_TO_PARA_ERROR(errno
);
859 if (chmod(name
, mode
) < 0)
868 * Prepare, create, and connect to a Unix domain socket for local communication.
870 * \param name The socket pathname.
872 * This function creates a local socket for sequenced, reliable, two-way,
873 * connection-based byte streams.
875 * \return The file descriptor, on success, negative on errors.
877 * \sa create_local_socket(), unix(7), connect(2).
879 int create_remote_socket(const char *name
)
881 struct sockaddr_un unix_addr
;
884 ret
= init_unix_addr(&unix_addr
, name
);
887 fd
= socket(PF_UNIX
, SOCK_STREAM
, 0);
889 return -ERRNO_TO_PARA_ERROR(errno
);
890 if (connect(fd
, (struct sockaddr
*)&unix_addr
, sizeof(unix_addr
)) == -1) {
891 ret
= -ERRNO_TO_PARA_ERROR(errno
);
901 ssize_t
send_cred_buffer(int sock
, char *buf
)
903 return send_buffer(sock
, buf
);
905 int recv_cred_buffer(int fd
, char *buf
, size_t size
)
907 return recv_buffer(fd
, buf
, size
) > 0? 1 : -E_RECVMSG
;
909 #else /* HAVE_UCRED */
911 * Send \p NULL-terminated buffer and Unix credentials of the current process.
913 * \param sock The socket file descriptor.
914 * \param buf The buffer to be sent.
916 * \return On success, this call returns the number of characters sent. On
917 * error, \p -E_SENDMSG is returned.
919 * \sa sendmsg(2), okir's Black Hats Manual.
921 ssize_t
send_cred_buffer(int sock
, char *buf
)
923 char control
[sizeof(struct cmsghdr
) + sizeof(struct ucred
)];
925 struct cmsghdr
*cmsg
;
926 static struct iovec iov
;
932 iov
.iov_len
= strlen(buf
);
936 /* compose the message */
937 memset(&msg
, 0, sizeof(msg
));
940 msg
.msg_control
= control
;
941 msg
.msg_controllen
= sizeof(control
);
942 /* attach the ucred struct */
943 cmsg
= CMSG_FIRSTHDR(&msg
);
944 cmsg
->cmsg_level
= SOL_SOCKET
;
945 cmsg
->cmsg_type
= SCM_CREDENTIALS
;
946 cmsg
->cmsg_len
= CMSG_LEN(sizeof(struct ucred
));
947 *(struct ucred
*)CMSG_DATA(cmsg
) = c
;
948 msg
.msg_controllen
= cmsg
->cmsg_len
;
949 ret
= sendmsg(sock
, &msg
, 0);
955 static void dispose_fds(int *fds
, unsigned num
)
959 for (i
= 0; i
< num
; i
++)
964 * Receive a buffer and the Unix credentials of the sending process.
966 * \param fd the socket file descriptor.
967 * \param buf the buffer to store the message.
968 * \param size the size of \a buffer.
970 * \return negative on errors, the user id on success.
972 * \sa recvmsg(2), okir's Black Hats Manual.
974 int recv_cred_buffer(int fd
, char *buf
, size_t size
)
978 struct cmsghdr
*cmsg
;
984 setsockopt(fd
, SOL_SOCKET
, SO_PASSCRED
, &yes
, sizeof(int));
985 memset(&msg
, 0, sizeof(msg
));
986 memset(buf
, 0, size
);
991 msg
.msg_control
= control
;
992 msg
.msg_controllen
= sizeof(control
);
993 if (recvmsg(fd
, &msg
, 0) < 0)
995 result
= -E_SCM_CREDENTIALS
;
996 cmsg
= CMSG_FIRSTHDR(&msg
);
998 if (cmsg
->cmsg_level
== SOL_SOCKET
&& cmsg
->cmsg_type
999 == SCM_CREDENTIALS
) {
1000 memcpy(&cred
, CMSG_DATA(cmsg
), sizeof(struct ucred
));
1003 if (cmsg
->cmsg_level
== SOL_SOCKET
1004 && cmsg
->cmsg_type
== SCM_RIGHTS
) {
1005 dispose_fds((int *) CMSG_DATA(cmsg
),
1006 (cmsg
->cmsg_len
- CMSG_LEN(0))
1009 cmsg
= CMSG_NXTHDR(&msg
, cmsg
);
1013 #endif /* HAVE_UCRED */
1016 * Receive a buffer and check for a pattern.
1018 * \param fd The file descriptor to receive from.
1019 * \param pattern The expected pattern.
1020 * \param bufsize The size of the internal buffer.
1022 * \return Positive if \a pattern was received, negative otherwise.
1024 * This function tries to receive at most \a bufsize bytes from file descriptor
1025 * \a fd. If at least \p strlen(\a pattern) bytes were received, the beginning
1026 * of the received buffer is compared with \a pattern, ignoring case.
1028 * \sa recv_buffer(), \sa strncasecmp(3).
1030 int recv_pattern(int fd
, const char *pattern
, size_t bufsize
)
1032 size_t len
= strlen(pattern
);
1033 char *buf
= para_malloc(bufsize
+ 1);
1034 int ret
= -E_RECV_PATTERN
, n
= recv_buffer(fd
, buf
, bufsize
+ 1);
1038 if (strncasecmp(buf
, pattern
, len
))
1043 PARA_NOTICE_LOG("did not receive pattern '%s'\n", pattern
);
1045 PARA_NOTICE_LOG("recvd %d bytes: %s\n", n
, buf
);
1047 PARA_NOTICE_LOG("%s\n", para_strerror(-n
));