diff options
| -rw-r--r-- | src/resolve/resolved-dns-packet.c | 96 | ||||
| -rw-r--r-- | src/resolve/resolved-dns-packet.h | 8 | ||||
| -rw-r--r-- | src/resolve/resolved-dns-rr.c | 73 | ||||
| -rw-r--r-- | src/resolve/resolved-dns-rr.h | 13 |
4 files changed, 165 insertions, 25 deletions
diff --git a/src/resolve/resolved-dns-packet.c b/src/resolve/resolved-dns-packet.c index f23b3cf893..472486777c 100644 --- a/src/resolve/resolved-dns-packet.c +++ b/src/resolve/resolved-dns-packet.c @@ -370,6 +370,28 @@ int dns_packet_append_string(DnsPacket *p, const char *s, size_t *start) { return 0; } +int dns_packet_append_raw_string(DnsPacket *p, const void *s, size_t size, size_t *start) { + void *d; + int r; + + assert(p); + assert(s || size == 0); + + if (size > 255) + return -E2BIG; + + r = dns_packet_extend(p, 1 + size, &d, start); + if (r < 0) + return r; + + ((uint8_t*) d)[0] = (uint8_t) size; + + if (size > 0) + memcpy(((uint8_t*) d) + 1, s, size); + + return 0; +} + int dns_packet_append_label(DnsPacket *p, const char *d, size_t l, size_t *start) { void *w; int r; @@ -643,19 +665,20 @@ int dns_packet_append_rr(DnsPacket *p, const DnsResourceRecord *rr, size_t *star break; case DNS_TYPE_SPF: /* exactly the same as TXT */ - case DNS_TYPE_TXT: { - char **s; + case DNS_TYPE_TXT: - if (strv_isempty(rr->txt.strings)) { + if (!rr->txt.items) { /* RFC 6763, section 6.1 suggests to generate * single empty string for an empty array. */ - r = dns_packet_append_string(p, "", NULL); + r = dns_packet_append_raw_string(p, NULL, 0, NULL); if (r < 0) goto fail; } else { - STRV_FOREACH(s, rr->txt.strings) { - r = dns_packet_append_string(p, *s, NULL); + DnsTxtItem *i; + + LIST_FOREACH(items, i, rr->txt.items) { + r = dns_packet_append_raw_string(p, i->data, i->length, NULL); if (r < 0) goto fail; } @@ -663,7 +686,6 @@ int dns_packet_append_rr(DnsPacket *p, const DnsResourceRecord *rr, size_t *star r = 0; break; - } case DNS_TYPE_A: r = dns_packet_append_blob(p, &rr->a.in_addr, sizeof(struct in_addr), NULL); @@ -1062,6 +1084,35 @@ fail: return r; } +int dns_packet_read_raw_string(DnsPacket *p, const void **ret, size_t *size, size_t *start) { + size_t saved_rindex; + uint8_t c; + int r; + + assert(p); + + saved_rindex = p->rindex; + + r = dns_packet_read_uint8(p, &c, NULL); + if (r < 0) + goto fail; + + r = dns_packet_read(p, c, ret, NULL); + if (r < 0) + goto fail; + + if (size) + *size = c; + if (start) + *start = saved_rindex; + + return 0; + +fail: + dns_packet_rewind(p, saved_rindex); + return r; +} + int dns_packet_read_name( DnsPacket *p, char **_ret, @@ -1412,24 +1463,37 @@ int dns_packet_read_rr(DnsPacket *p, DnsResourceRecord **ret, size_t *start) { case DNS_TYPE_SPF: /* exactly the same as TXT */ case DNS_TYPE_TXT: if (rdlength <= 0) { + DnsTxtItem *i; /* RFC 6763, section 6.1 suggests to treat * empty TXT RRs as equivalent to a TXT record * with a single empty string. */ - r = strv_extend(&rr->txt.strings, ""); - if (r < 0) - goto fail; + i = malloc0(offsetof(DnsTxtItem, data) + 1); /* for safety reasons we add an extra NUL byte */ + if (!i) + return -ENOMEM; + + rr->txt.items = i; } else { + DnsTxtItem *last = NULL; + while (p->rindex < offset + rdlength) { - char *s; + DnsTxtItem *i; + const void *data; + size_t sz; - r = dns_packet_read_string(p, &s, NULL); + r = dns_packet_read_raw_string(p, &data, &sz, NULL); if (r < 0) - goto fail; + return r; - r = strv_consume(&rr->txt.strings, s); - if (r < 0) - goto fail; + i = malloc0(offsetof(DnsTxtItem, data) + sz + 1); /* extra NUL byte at the end */ + if (!i) + return -ENOMEM; + + memcpy(i->data, data, sz); + i->length = sz; + + LIST_INSERT_AFTER(items, rr->txt.items, last, i); + last = i; } } diff --git a/src/resolve/resolved-dns-packet.h b/src/resolve/resolved-dns-packet.h index 73803e4e82..48df5dfc53 100644 --- a/src/resolve/resolved-dns-packet.h +++ b/src/resolve/resolved-dns-packet.h @@ -155,9 +155,9 @@ int dns_packet_append_uint8(DnsPacket *p, uint8_t v, size_t *start); int dns_packet_append_uint16(DnsPacket *p, uint16_t v, size_t *start); int dns_packet_append_uint32(DnsPacket *p, uint32_t v, size_t *start); int dns_packet_append_string(DnsPacket *p, const char *s, size_t *start); +int dns_packet_append_raw_string(DnsPacket *p, const void *s, size_t size, size_t *start); int dns_packet_append_label(DnsPacket *p, const char *s, size_t l, size_t *start); -int dns_packet_append_name(DnsPacket *p, const char *name, - bool allow_compression, size_t *start); +int dns_packet_append_name(DnsPacket *p, const char *name, bool allow_compression, size_t *start); int dns_packet_append_key(DnsPacket *p, const DnsResourceKey *key, size_t *start); int dns_packet_append_rr(DnsPacket *p, const DnsResourceRecord *rr, size_t *start); @@ -167,8 +167,8 @@ int dns_packet_read_uint8(DnsPacket *p, uint8_t *ret, size_t *start); int dns_packet_read_uint16(DnsPacket *p, uint16_t *ret, size_t *start); int dns_packet_read_uint32(DnsPacket *p, uint32_t *ret, size_t *start); int dns_packet_read_string(DnsPacket *p, char **ret, size_t *start); -int dns_packet_read_name(DnsPacket *p, char **ret, - bool allow_compression, size_t *start); +int dns_packet_read_raw_string(DnsPacket *p, const void **ret, size_t *size, size_t *start); +int dns_packet_read_name(DnsPacket *p, char **ret, bool allow_compression, size_t *start); int dns_packet_read_key(DnsPacket *p, DnsResourceKey **ret, size_t *start); int dns_packet_read_rr(DnsPacket *p, DnsResourceRecord **ret, size_t *start); diff --git a/src/resolve/resolved-dns-rr.c b/src/resolve/resolved-dns-rr.c index ba2ea686f3..636e07dea9 100644 --- a/src/resolve/resolved-dns-rr.c +++ b/src/resolve/resolved-dns-rr.c @@ -273,7 +273,7 @@ DnsResourceRecord* dns_resource_record_unref(DnsResourceRecord *rr) { case DNS_TYPE_TXT: case DNS_TYPE_SPF: - strv_free(rr->txt.strings); + dns_txt_item_free_all(rr->txt.items); break; case DNS_TYPE_SOA: @@ -430,7 +430,7 @@ int dns_resource_record_equal(const DnsResourceRecord *a, const DnsResourceRecor case DNS_TYPE_SPF: /* exactly the same as TXT */ case DNS_TYPE_TXT: - return strv_equal(a->txt.strings, b->txt.strings); + return dns_txt_item_equal(a->txt.items, b->txt.items); case DNS_TYPE_A: return memcmp(&a->a.in_addr, &b->a.in_addr, sizeof(struct in_addr)) == 0; @@ -600,6 +600,43 @@ static char *format_types(Bitmap *types) { return strjoin("( ", str, " )", NULL); } +static char *format_txt(DnsTxtItem *first) { + DnsTxtItem *i; + size_t c = 1; + char *p, *s; + + LIST_FOREACH(items, i, first) + c += i->length * 4 + 3; + + p = s = new(char, c); + if (!s) + return NULL; + + LIST_FOREACH(items, i, first) { + size_t j; + + if (i != first) + *(p++) = ' '; + + *(p++) = '"'; + + for (j = 0; j < i->length; j++) { + if (i->data[j] < ' ' || i->data[j] == '"' || i->data[j] >= 127) { + *(p++) = '\\'; + *(p++) = '0' + (i->data[j] / 100); + *(p++) = '0' + ((i->data[j] / 10) % 10); + *(p++) = '0' + (i->data[j] % 10); + } else + *(p++) = i->data[j]; + } + + *(p++) = '"'; + } + + *p = 0; + return s; +} + int dns_resource_record_to_string(const DnsResourceRecord *rr, char **ret) { _cleanup_free_ char *k = NULL, *t = NULL; char *s; @@ -642,14 +679,13 @@ int dns_resource_record_to_string(const DnsResourceRecord *rr, char **ret) { case DNS_TYPE_SPF: /* exactly the same as TXT */ case DNS_TYPE_TXT: - t = strv_join_quoted(rr->txt.strings); + t = format_txt(rr->txt.items); if (!t) return -ENOMEM; s = strjoin(k, " ", t, NULL); if (!s) return -ENOMEM; - break; case DNS_TYPE_A: { @@ -890,3 +926,32 @@ int dns_class_from_string(const char *s, uint16_t *class) { return 0; } + +DnsTxtItem *dns_txt_item_free_all(DnsTxtItem *i) { + DnsTxtItem *n; + + if (!i) + return NULL; + + n = i->items_next; + + free(i); + return dns_txt_item_free_all(n); +} + +bool dns_txt_item_equal(DnsTxtItem *a, DnsTxtItem *b) { + + if (!a != !b) + return false; + + if (!a) + return true; + + if (a->length != b->length) + return false; + + if (memcmp(a->data, b->data, a->length) != 0) + return false; + + return dns_txt_item_equal(a->items_next, b->items_next); +} diff --git a/src/resolve/resolved-dns-rr.h b/src/resolve/resolved-dns-rr.h index a23546f757..c02f2ec00f 100644 --- a/src/resolve/resolved-dns-rr.h +++ b/src/resolve/resolved-dns-rr.h @@ -27,9 +27,11 @@ #include "dns-type.h" #include "hashmap.h" #include "in-addr-util.h" +#include "list.h" typedef struct DnsResourceKey DnsResourceKey; typedef struct DnsResourceRecord DnsResourceRecord; +typedef struct DnsTxtItem DnsTxtItem; /* DNS record classes, see RFC 1035 */ enum { @@ -45,6 +47,12 @@ struct DnsResourceKey { char *_name; /* don't access directy, use DNS_RESOURCE_KEY_NAME()! */ }; +struct DnsTxtItem { + size_t length; + LIST_FIELDS(DnsTxtItem, items); + uint8_t data[]; +}; + struct DnsResourceRecord { unsigned n_ref; DnsResourceKey *key; @@ -73,7 +81,7 @@ struct DnsResourceRecord { } hinfo; struct { - char **strings; + DnsTxtItem *items; } txt, spf; struct { @@ -198,6 +206,9 @@ int dns_resource_record_equal(const DnsResourceRecord *a, const DnsResourceRecor int dns_resource_record_to_string(const DnsResourceRecord *rr, char **ret); DEFINE_TRIVIAL_CLEANUP_FUNC(DnsResourceRecord*, dns_resource_record_unref); +DnsTxtItem *dns_txt_item_free_all(DnsTxtItem *i); +bool dns_txt_item_equal(DnsTxtItem *a, DnsTxtItem *b); + const char *dns_class_to_string(uint16_t type); int dns_class_from_string(const char *name, uint16_t *class); |