From 943a6b93697fc0a7bcd0cc574744d7de609c189c Mon Sep 17 00:00:00 2001 From: Lennart Poettering Date: Tue, 25 Oct 2005 19:24:40 +0000 Subject: * add new core API functions avahi_rdata_serialize() and avahi_rdata_parse() * add new definition AVAHI_DNS_RDATA_MAX * update dns-test.c and add examples for avahi_rdata_{serialize,parse}() git-svn-id: file:///home/lennart/svn/public/avahi/trunk@867 941a03a8-eaeb-0310-b9a0-b1bbd8fe43fe --- avahi-core/dns.c | 200 ++++++++++++++++++++++++++++++++++--------------------- 1 file changed, 124 insertions(+), 76 deletions(-) (limited to 'avahi-core/dns.c') diff --git a/avahi-core/dns.c b/avahi-core/dns.c index 8c8b42b..63ea8a0 100644 --- a/avahi-core/dns.c +++ b/avahi-core/dns.c @@ -56,6 +56,7 @@ AvahiDnsPacket* avahi_dns_packet_new(unsigned mtu) { p->size = p->rindex = AVAHI_DNS_PACKET_HEADER_SIZE; p->max_size = max_size; p->name_table = NULL; + p->data = NULL; memset(AVAHI_DNS_PACKET_DATA(p), 0, p->size); return p; @@ -495,88 +496,58 @@ int avahi_dns_packet_skip(AvahiDnsPacket *p, size_t length) { return 0; } -AvahiRecord* avahi_dns_packet_consume_record(AvahiDnsPacket *p, int *ret_cache_flush) { - char name[257], buf[257]; - uint16_t type, class; - uint32_t ttl; - uint16_t rdlength; - AvahiRecord *r = NULL; +static int parse_rdata(AvahiDnsPacket *p, AvahiRecord *r, uint16_t rdlength) { + char buf[AVAHI_DOMAIN_NAME_MAX]; const void* start; - + assert(p); + assert(r); -/* avahi_log_debug("consume_record()"); */ - - if (avahi_dns_packet_consume_name(p, name, sizeof(name)) < 0 || - avahi_dns_packet_consume_uint16(p, &type) < 0 || - avahi_dns_packet_consume_uint16(p, &class) < 0 || - avahi_dns_packet_consume_uint32(p, &ttl) < 0 || - avahi_dns_packet_consume_uint16(p, &rdlength) < 0 || - p->rindex + rdlength > p->size) - goto fail; - -/* avahi_log_debug("name = %s, rdlength = %u", name, rdlength); */ - - if (ret_cache_flush) - *ret_cache_flush = !!(class & AVAHI_DNS_CACHE_FLUSH); - class &= ~AVAHI_DNS_CACHE_FLUSH; - start = avahi_dns_packet_get_rptr(p); - - if (!(r = avahi_record_new_full(name, class, type, ttl))) - return NULL; - - switch (type) { + + switch (r->key->type) { case AVAHI_DNS_TYPE_PTR: case AVAHI_DNS_TYPE_CNAME: case AVAHI_DNS_TYPE_NS: - -/* avahi_log_debug("ptr"); */ if (avahi_dns_packet_consume_name(p, buf, sizeof(buf)) < 0) - goto fail; + return -1; r->data.ptr.name = avahi_strdup(buf); break; case AVAHI_DNS_TYPE_SRV: - -/* avahi_log_debug("srv"); */ if (avahi_dns_packet_consume_uint16(p, &r->data.srv.priority) < 0 || avahi_dns_packet_consume_uint16(p, &r->data.srv.weight) < 0 || avahi_dns_packet_consume_uint16(p, &r->data.srv.port) < 0 || avahi_dns_packet_consume_name(p, buf, sizeof(buf)) < 0) - goto fail; + return -1; r->data.srv.name = avahi_strdup(buf); break; case AVAHI_DNS_TYPE_HINFO: - -/* avahi_log_debug("hinfo"); */ if (avahi_dns_packet_consume_string(p, buf, sizeof(buf)) < 0) - goto fail; - + return -1; + r->data.hinfo.cpu = avahi_strdup(buf); - + if (avahi_dns_packet_consume_string(p, buf, sizeof(buf)) < 0) - goto fail; - + return -1; + r->data.hinfo.os = avahi_strdup(buf); break; case AVAHI_DNS_TYPE_TXT: -/* avahi_log_debug("txt"); */ - if (rdlength > 0) { r->data.txt.string_list = avahi_string_list_parse(avahi_dns_packet_get_rptr(p), rdlength); if (avahi_dns_packet_skip(p, rdlength) < 0) - goto fail; + return -1; } else r->data.txt.string_list = NULL; @@ -587,7 +558,7 @@ AvahiRecord* avahi_dns_packet_consume_record(AvahiDnsPacket *p, int *ret_cache_f /* avahi_log_debug("A"); */ if (avahi_dns_packet_consume_bytes(p, &r->data.a.address, sizeof(AvahiIPv4Address)) < 0) - goto fail; + return -1; break; @@ -596,7 +567,7 @@ AvahiRecord* avahi_dns_packet_consume_record(AvahiDnsPacket *p, int *ret_cache_f /* avahi_log_debug("aaaa"); */ if (avahi_dns_packet_consume_bytes(p, &r->data.aaaa.address, sizeof(AvahiIPv6Address)) < 0) - goto fail; + return -1; break; @@ -609,18 +580,46 @@ AvahiRecord* avahi_dns_packet_consume_record(AvahiDnsPacket *p, int *ret_cache_f r->data.generic.data = avahi_memdup(avahi_dns_packet_get_rptr(p), rdlength); if (avahi_dns_packet_skip(p, rdlength) < 0) - goto fail; + return -1; } break; } -/* avahi_log_debug("%i == %u ?", (uint8_t*) avahi_dns_packet_get_rptr(p) - (uint8_t*) start, rdlength); */ - /* Check if we read enough data */ if ((const uint8_t*) avahi_dns_packet_get_rptr(p) - (const uint8_t*) start != rdlength) + return -1; + + return 0; +} + +AvahiRecord* avahi_dns_packet_consume_record(AvahiDnsPacket *p, int *ret_cache_flush) { + char name[AVAHI_DOMAIN_NAME_MAX]; + uint16_t type, class; + uint32_t ttl; + uint16_t rdlength; + AvahiRecord *r = NULL; + + assert(p); + + if (avahi_dns_packet_consume_name(p, name, sizeof(name)) < 0 || + avahi_dns_packet_consume_uint16(p, &type) < 0 || + avahi_dns_packet_consume_uint16(p, &class) < 0 || + avahi_dns_packet_consume_uint32(p, &ttl) < 0 || + avahi_dns_packet_consume_uint16(p, &rdlength) < 0 || + p->rindex + rdlength > p->size) goto fail; + if (ret_cache_flush) + *ret_cache_flush = !!(class & AVAHI_DNS_CACHE_FLUSH); + class &= ~AVAHI_DNS_CACHE_FLUSH; + + if (!(r = avahi_record_new_full(name, class, type, ttl))) + goto fail; + + if (parse_rdata(p, r, rdlength) < 0) + goto fail; + return r; fail: @@ -668,24 +667,10 @@ uint8_t* avahi_dns_packet_append_key(AvahiDnsPacket *p, AvahiKey *k, int unicast return t; } -uint8_t* avahi_dns_packet_append_record(AvahiDnsPacket *p, AvahiRecord *r, int cache_flush, unsigned max_ttl) { - uint8_t *t, *l, *start; - size_t size; - +static int append_rdata(AvahiDnsPacket *p, AvahiRecord *r) { assert(p); assert(r); - - size = p->size; - - if (!(t = avahi_dns_packet_append_name(p, r->key->name)) || - !avahi_dns_packet_append_uint16(p, r->key->type) || - !avahi_dns_packet_append_uint16(p, cache_flush ? (r->key->clazz | AVAHI_DNS_CACHE_FLUSH) : (r->key->clazz &~ AVAHI_DNS_CACHE_FLUSH)) || - !avahi_dns_packet_append_uint32(p, (max_ttl && r->ttl > max_ttl) ? max_ttl : r->ttl) || - !(l = avahi_dns_packet_append_uint16(p, 0))) - goto fail; - - start = avahi_dns_packet_extend(p, 0); - + switch (r->key->type) { case AVAHI_DNS_TYPE_PTR: @@ -693,7 +678,7 @@ uint8_t* avahi_dns_packet_append_record(AvahiDnsPacket *p, AvahiRecord *r, int c case AVAHI_DNS_TYPE_NS: if (!(avahi_dns_packet_append_name(p, r->data.ptr.name))) - goto fail; + return -1; break; @@ -703,14 +688,14 @@ uint8_t* avahi_dns_packet_append_record(AvahiDnsPacket *p, AvahiRecord *r, int c !avahi_dns_packet_append_uint16(p, r->data.srv.weight) || !avahi_dns_packet_append_uint16(p, r->data.srv.port) || !avahi_dns_packet_append_name(p, r->data.srv.name)) - goto fail; + return -1; break; case AVAHI_DNS_TYPE_HINFO: if (!avahi_dns_packet_append_string(p, r->data.hinfo.cpu) || !avahi_dns_packet_append_string(p, r->data.hinfo.os)) - goto fail; + return -1; break; @@ -721,10 +706,8 @@ uint8_t* avahi_dns_packet_append_record(AvahiDnsPacket *p, AvahiRecord *r, int c n = avahi_string_list_serialize(r->data.txt.string_list, NULL, 0); -/* avahi_log_debug("appending string: %u %p", n, r->data.txt.string_list); */ - if (!(data = avahi_dns_packet_extend(p, n))) - goto fail; + return -1; avahi_string_list_serialize(r->data.txt.string_list, data, n); break; @@ -734,28 +717,50 @@ uint8_t* avahi_dns_packet_append_record(AvahiDnsPacket *p, AvahiRecord *r, int c case AVAHI_DNS_TYPE_A: if (!avahi_dns_packet_append_bytes(p, &r->data.a.address, sizeof(r->data.a.address))) - goto fail; + return -1; break; case AVAHI_DNS_TYPE_AAAA: if (!avahi_dns_packet_append_bytes(p, &r->data.aaaa.address, sizeof(r->data.aaaa.address))) - goto fail; + return -1; break; default: - if (r->data.generic.size && - avahi_dns_packet_append_bytes(p, r->data.generic.data, r->data.generic.size)) - goto fail; + if (r->data.generic.size) + if (avahi_dns_packet_append_bytes(p, r->data.generic.data, r->data.generic.size)) + return -1; break; } + return 0; +} + +uint8_t* avahi_dns_packet_append_record(AvahiDnsPacket *p, AvahiRecord *r, int cache_flush, unsigned max_ttl) { + uint8_t *t, *l, *start; + size_t size; + + assert(p); + assert(r); + + size = p->size; + + if (!(t = avahi_dns_packet_append_name(p, r->key->name)) || + !avahi_dns_packet_append_uint16(p, r->key->type) || + !avahi_dns_packet_append_uint16(p, cache_flush ? (r->key->clazz | AVAHI_DNS_CACHE_FLUSH) : (r->key->clazz &~ AVAHI_DNS_CACHE_FLUSH)) || + !avahi_dns_packet_append_uint32(p, (max_ttl && r->ttl > max_ttl) ? max_ttl : r->ttl) || + !(l = avahi_dns_packet_append_uint16(p, 0))) + goto fail; + + start = avahi_dns_packet_extend(p, 0); + if (append_rdata(p, r) < 0) + goto fail; size = avahi_dns_packet_extend(p, 0) - start; assert(size <= 0xFFFF); @@ -786,3 +791,46 @@ size_t avahi_dns_packet_space(AvahiDnsPacket *p) { return p->max_size - p->size; } + +int avahi_rdata_parse(AvahiRecord *record, const void* rdata, size_t size) { + int ret; + AvahiDnsPacket p; + + assert(record); + assert(rdata); + + p.data = (void*) rdata; + p.max_size = p.size = size; + p.rindex = 0; + p.name_table = NULL; + + ret = parse_rdata(&p, record, size); + + assert(!p.name_table); + + return ret; +} + +size_t avahi_rdata_serialize(AvahiRecord *record, void *rdata, size_t max_size) { + int ret; + AvahiDnsPacket p; + + assert(record); + assert(rdata); + assert(max_size > 0); + + p.data = (void*) rdata; + p.max_size = max_size; + p.size = p.rindex = 0; + p.name_table = NULL; + + ret = append_rdata(&p, record); + + if (p.name_table) + avahi_hashmap_free(p.name_table); + + if (ret < 0) + return (size_t) -1; + + return p.size; +} -- cgit