diff options
Diffstat (limited to 'lib/libcapsicum/libcapsicum_dns.c')
| -rw-r--r-- | lib/libcapsicum/libcapsicum_dns.c | 365 |
1 files changed, 365 insertions, 0 deletions
diff --git a/lib/libcapsicum/libcapsicum_dns.c b/lib/libcapsicum/libcapsicum_dns.c new file mode 100644 index 0000000..a180b6b --- /dev/null +++ b/lib/libcapsicum/libcapsicum_dns.c @@ -0,0 +1,365 @@ +/*- + * Copyright (c) 2012-2013 The FreeBSD Foundation + * All rights reserved. + * + * This software was developed by Pawel Jakub Dawidek under sponsorship from + * the FreeBSD Foundation. + * + * Redistribution and use in source and binary forms, with or without + * modification, are permitted provided that the following conditions + * are met: + * 1. Redistributions of source code must retain the above copyright + * notice, this list of conditions and the following disclaimer. + * 2. Redistributions in binary form must reproduce the above copyright + * notice, this list of conditions and the following disclaimer in the + * documentation and/or other materials provided with the distribution. + * + * THIS SOFTWARE IS PROVIDED BY THE AUTHORS AND CONTRIBUTORS ``AS IS'' AND + * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE + * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE + * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHORS OR CONTRIBUTORS BE LIABLE + * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL + * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS + * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) + * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT + * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY + * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF + * SUCH DAMAGE. + */ + +#include <sys/cdefs.h> +__FBSDID("$FreeBSD$"); + +#include <assert.h> +#include <netdb.h> +#include <stdlib.h> +#include <string.h> +#include <unistd.h> + +#include <nv.h> + +#include "libcapsicum.h" +#include "libcapsicum_dns.h" + +static struct hostent hent; + +static void +hostent_free(struct hostent *hp) +{ + unsigned int ii; + + free(hp->h_name); + hp->h_name = NULL; + if (hp->h_aliases != NULL) { + for (ii = 0; hp->h_aliases[ii] != NULL; ii++) + free(hp->h_aliases[ii]); + free(hp->h_aliases); + hp->h_aliases = NULL; + } + if (hp->h_addr_list != NULL) { + for (ii = 0; hp->h_addr_list[ii] != NULL; ii++) + free(hp->h_addr_list[ii]); + free(hp->h_addr_list); + hp->h_addr_list = NULL; + } +} + +static struct hostent * +hostent_unpack(const nvlist_t *nvl, struct hostent *hp) +{ + unsigned int ii, nitems; + char nvlname[64]; + int n; + + hostent_free(hp); + + hp->h_name = strdup(nvlist_get_string(nvl, "name")); + if (hp->h_name == NULL) + goto fail; + hp->h_addrtype = (int)nvlist_get_number(nvl, "addrtype"); + hp->h_length = (int)nvlist_get_number(nvl, "length"); + + nitems = (unsigned int)nvlist_get_number(nvl, "naliases"); + hp->h_aliases = calloc(sizeof(hp->h_aliases[0]), nitems + 1); + if (hp->h_aliases == NULL) + goto fail; + for (ii = 0; ii < nitems; ii++) { + n = snprintf(nvlname, sizeof(nvlname), "alias%u", ii); + assert(n > 0 && n < (int)sizeof(nvlname)); + hp->h_aliases[ii] = + strdup(nvlist_get_string(nvl, nvlname)); + if (hp->h_aliases[ii] == NULL) + goto fail; + } + hp->h_aliases[ii] = NULL; + + nitems = (unsigned int)nvlist_get_number(nvl, "naddrs"); + hp->h_addr_list = calloc(sizeof(hp->h_addr_list[0]), nitems + 1); + if (hp->h_addr_list == NULL) + goto fail; + for (ii = 0; ii < nitems; ii++) { + hp->h_addr_list[ii] = malloc(hp->h_length); + if (hp->h_addr_list[ii] == NULL) + goto fail; + n = snprintf(nvlname, sizeof(nvlname), "addr%u", ii); + assert(n > 0 && n < (int)sizeof(nvlname)); + bcopy(nvlist_get_binary(nvl, nvlname, NULL), + hp->h_addr_list[ii], hp->h_length); + } + hp->h_addr_list[ii] = NULL; + + return (hp); +fail: + hostent_free(hp); + h_errno = NO_RECOVERY; + return (NULL); +} + +struct hostent * +cap_gethostbyname(cap_channel_t *chan, const char *name) +{ + + return (cap_gethostbyname2(chan, name, AF_INET)); +} + +struct hostent * +cap_gethostbyname2(cap_channel_t *chan, const char *name, int type) +{ + struct hostent *hp; + nvlist_t *nvl; + + nvl = nvlist_create(0); + nvlist_add_string(nvl, "cmd", "gethostbyname"); + nvlist_add_number(nvl, "family", (uint64_t)type); + nvlist_add_string(nvl, "name", name); + nvl = cap_xfer_nvlist(chan, nvl, 0); + if (nvl == NULL) { + h_errno = NO_RECOVERY; + return (NULL); + } + if (nvlist_get_number(nvl, "error") != 0) { + h_errno = (int)nvlist_get_number(nvl, "error"); + nvlist_destroy(nvl); + return (NULL); + } + + hp = hostent_unpack(nvl, &hent); + nvlist_destroy(nvl); + return (hp); +} + +struct hostent * +cap_gethostbyaddr(cap_channel_t *chan, const void *addr, socklen_t len, + int type) +{ + struct hostent *hp; + nvlist_t *nvl; + + nvl = nvlist_create(0); + nvlist_add_string(nvl, "cmd", "gethostbyaddr"); + nvlist_add_binary(nvl, "addr", addr, (size_t)len); + nvlist_add_number(nvl, "family", (uint64_t)type); + nvl = cap_xfer_nvlist(chan, nvl, 0); + if (nvl == NULL) { + h_errno = NO_RECOVERY; + return (NULL); + } + if (nvlist_get_number(nvl, "error") != 0) { + h_errno = (int)nvlist_get_number(nvl, "error"); + nvlist_destroy(nvl); + return (NULL); + } + hp = hostent_unpack(nvl, &hent); + nvlist_destroy(nvl); + return (hp); +} + +static struct addrinfo * +addrinfo_unpack(const nvlist_t *nvl) +{ + struct addrinfo *ai; + const void *addr; + size_t addrlen; + const char *canonname; + + addr = nvlist_get_binary(nvl, "ai_addr", &addrlen); + ai = malloc(sizeof(*ai) + addrlen); + if (ai == NULL) + return (NULL); + ai->ai_flags = (int)nvlist_get_number(nvl, "ai_flags"); + ai->ai_family = (int)nvlist_get_number(nvl, "ai_family"); + ai->ai_socktype = (int)nvlist_get_number(nvl, "ai_socktype"); + ai->ai_protocol = (int)nvlist_get_number(nvl, "ai_protocol"); + ai->ai_addrlen = (socklen_t)addrlen; + canonname = nvlist_get_string(nvl, "ai_canonname"); + if (canonname != NULL) { + ai->ai_canonname = strdup(canonname); + if (ai->ai_canonname == NULL) { + free(ai); + return (NULL); + } + } else { + ai->ai_canonname = NULL; + } + ai->ai_addr = (void *)(ai + 1); + bcopy(addr, ai->ai_addr, addrlen); + ai->ai_next = NULL; + + return (ai); +} + +int +cap_getaddrinfo(cap_channel_t *chan, const char *hostname, const char *servname, + const struct addrinfo *hints, struct addrinfo **res) +{ + struct addrinfo *firstai, *prevai, *curai; + unsigned int ii; + const nvlist_t *nvlai; + char nvlname[64]; + nvlist_t *nvl; + int error, n; + + nvl = nvlist_create(0); + nvlist_add_string(nvl, "cmd", "getaddrinfo"); + nvlist_add_string(nvl, "hostname", hostname); + nvlist_add_string(nvl, "servname", servname); + if (hints != NULL) { + nvlist_add_number(nvl, "hints.ai_flags", + (uint64_t)hints->ai_flags); + nvlist_add_number(nvl, "hints.ai_family", + (uint64_t)hints->ai_family); + nvlist_add_number(nvl, "hints.ai_socktype", + (uint64_t)hints->ai_socktype); + nvlist_add_number(nvl, "hints.ai_protocol", + (uint64_t)hints->ai_protocol); + } + nvl = cap_xfer_nvlist(chan, nvl, 0); + if (nvl == NULL) + return (EAI_MEMORY); + if (nvlist_get_number(nvl, "error") != 0) { + error = (int)nvlist_get_number(nvl, "error"); + nvlist_destroy(nvl); + return (error); + } + + nvlai = NULL; + firstai = prevai = curai = NULL; + for (ii = 0; ; ii++) { + n = snprintf(nvlname, sizeof(nvlname), "res%u", ii); + assert(n > 0 && n < (int)sizeof(nvlname)); + if (!nvlist_exists_nvlist(nvl, nvlname)) + break; + nvlai = nvlist_get_nvlist(nvl, nvlname); + curai = addrinfo_unpack(nvlai); + if (curai == NULL) + break; + if (prevai != NULL) + prevai->ai_next = curai; + else if (firstai == NULL) + firstai = curai; + prevai = curai; + } + nvlist_destroy(nvl); + if (curai == NULL && nvlai != NULL) { + if (firstai == NULL) + freeaddrinfo(firstai); + return (EAI_MEMORY); + } + + *res = firstai; + return (0); +} + +int +cap_getnameinfo(cap_channel_t *chan, const struct sockaddr *sa, socklen_t salen, + char *host, size_t hostlen, char *serv, size_t servlen, int flags) +{ + nvlist_t *nvl; + int error; + + nvl = nvlist_create(0); + nvlist_add_string(nvl, "cmd", "getnameinfo"); + nvlist_add_number(nvl, "hostlen", (uint64_t)hostlen); + nvlist_add_number(nvl, "servlen", (uint64_t)servlen); + nvlist_add_binary(nvl, "sa", sa, (size_t)salen); + nvlist_add_number(nvl, "flags", (uint64_t)flags); + nvl = cap_xfer_nvlist(chan, nvl, 0); + if (nvl == NULL) + return (EAI_MEMORY); + if (nvlist_get_number(nvl, "error") != 0) { + error = (int)nvlist_get_number(nvl, "error"); + nvlist_destroy(nvl); + return (error); + } + + if (host != NULL) + strlcpy(host, nvlist_get_string(nvl, "host"), hostlen + 1); + if (serv != NULL) + strlcpy(serv, nvlist_get_string(nvl, "serv"), servlen + 1); + nvlist_destroy(nvl); + return (0); +} + +static void +limit_remove(nvlist_t *limits, const char *prefix) +{ + const char *name; + size_t prefixlen; + void *cookie; + + prefixlen = strlen(prefix); +again: + cookie = NULL; + while ((name = nvlist_next(limits, NULL, &cookie)) != NULL) { + if (strncmp(name, prefix, prefixlen) == 0) { + nvlist_free(limits, name); + goto again; + } + } +} + +int +cap_dns_type_limit(cap_channel_t *chan, const char * const *types, + size_t ntypes) +{ + nvlist_t *limits; + unsigned int i; + char nvlname[64]; + int n; + + if (cap_limit_get(chan, &limits) < 0) + return (-1); + if (limits == NULL) + limits = nvlist_create(0); + else + limit_remove(limits, "type"); + for (i = 0; i < ntypes; i++) { + n = snprintf(nvlname, sizeof(nvlname), "type%u", i); + assert(n > 0 && n < (int)sizeof(nvlname)); + nvlist_add_string(limits, nvlname, types[i]); + } + return (cap_limit_set(chan, limits)); +} + +int +cap_dns_family_limit(cap_channel_t *chan, const int *families, + size_t nfamilies) +{ + nvlist_t *limits; + unsigned int i; + char nvlname[64]; + int n; + + if (cap_limit_get(chan, &limits) < 0) + return (-1); + if (limits == NULL) + limits = nvlist_create(0); + else + limit_remove(limits, "family"); + for (i = 0; i < nfamilies; i++) { + n = snprintf(nvlname, sizeof(nvlname), "family%u", i); + assert(n > 0 && n < (int)sizeof(nvlname)); + nvlist_add_number(limits, nvlname, (uint64_t)families[i]); + } + return (cap_limit_set(chan, limits)); +} |
