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Diffstat (limited to 'libc-top-half/musl/src/network/ns_parse.c')
-rw-r--r--libc-top-half/musl/src/network/ns_parse.c171
1 files changed, 171 insertions, 0 deletions
diff --git a/libc-top-half/musl/src/network/ns_parse.c b/libc-top-half/musl/src/network/ns_parse.c
new file mode 100644
index 0000000..d01da47
--- /dev/null
+++ b/libc-top-half/musl/src/network/ns_parse.c
@@ -0,0 +1,171 @@
+#define _BSD_SOURCE
+#include <errno.h>
+#include <stddef.h>
+#include <resolv.h>
+#include <arpa/nameser.h>
+
+const struct _ns_flagdata _ns_flagdata[16] = {
+ { 0x8000, 15 },
+ { 0x7800, 11 },
+ { 0x0400, 10 },
+ { 0x0200, 9 },
+ { 0x0100, 8 },
+ { 0x0080, 7 },
+ { 0x0040, 6 },
+ { 0x0020, 5 },
+ { 0x0010, 4 },
+ { 0x000f, 0 },
+ { 0x0000, 0 },
+ { 0x0000, 0 },
+ { 0x0000, 0 },
+ { 0x0000, 0 },
+ { 0x0000, 0 },
+ { 0x0000, 0 },
+};
+
+unsigned ns_get16(const unsigned char *cp)
+{
+ return cp[0]<<8 | cp[1];
+}
+
+unsigned long ns_get32(const unsigned char *cp)
+{
+ return (unsigned)cp[0]<<24 | cp[1]<<16 | cp[2]<<8 | cp[3];
+}
+
+void ns_put16(unsigned s, unsigned char *cp)
+{
+ *cp++ = s>>8;
+ *cp++ = s;
+}
+
+void ns_put32(unsigned long l, unsigned char *cp)
+{
+ *cp++ = l>>24;
+ *cp++ = l>>16;
+ *cp++ = l>>8;
+ *cp++ = l;
+}
+
+int ns_initparse(const unsigned char *msg, int msglen, ns_msg *handle)
+{
+ int i, r;
+
+ handle->_msg = msg;
+ handle->_eom = msg + msglen;
+ if (msglen < (2 + ns_s_max) * NS_INT16SZ) goto bad;
+ NS_GET16(handle->_id, msg);
+ NS_GET16(handle->_flags, msg);
+ for (i = 0; i < ns_s_max; i++) NS_GET16(handle->_counts[i], msg);
+ for (i = 0; i < ns_s_max; i++) {
+ if (handle->_counts[i]) {
+ handle->_sections[i] = msg;
+ r = ns_skiprr(msg, handle->_eom, i, handle->_counts[i]);
+ if (r < 0) return -1;
+ msg += r;
+ } else {
+ handle->_sections[i] = NULL;
+ }
+ }
+ if (msg != handle->_eom) goto bad;
+ handle->_sect = ns_s_max;
+ handle->_rrnum = -1;
+ handle->_msg_ptr = NULL;
+ return 0;
+bad:
+ errno = EMSGSIZE;
+ return -1;
+}
+
+int ns_skiprr(const unsigned char *ptr, const unsigned char *eom, ns_sect section, int count)
+{
+ const unsigned char *p = ptr;
+ int r;
+
+ while (count--) {
+ r = dn_skipname(p, eom);
+ if (r < 0) goto bad;
+ if (r + 2 * NS_INT16SZ > eom - p) goto bad;
+ p += r + 2 * NS_INT16SZ;
+ if (section != ns_s_qd) {
+ if (NS_INT32SZ + NS_INT16SZ > eom - p) goto bad;
+ p += NS_INT32SZ;
+ NS_GET16(r, p);
+ if (r > eom - p) goto bad;
+ p += r;
+ }
+ }
+ return p - ptr;
+bad:
+ errno = EMSGSIZE;
+ return -1;
+}
+
+int ns_parserr(ns_msg *handle, ns_sect section, int rrnum, ns_rr *rr)
+{
+ int r;
+
+ if (section < 0 || section >= ns_s_max) goto bad;
+ if (section != handle->_sect) {
+ handle->_sect = section;
+ handle->_rrnum = 0;
+ handle->_msg_ptr = handle->_sections[section];
+ }
+ if (rrnum == -1) rrnum = handle->_rrnum;
+ if (rrnum < 0 || rrnum >= handle->_counts[section]) goto bad;
+ if (rrnum < handle->_rrnum) {
+ handle->_rrnum = 0;
+ handle->_msg_ptr = handle->_sections[section];
+ }
+ if (rrnum > handle->_rrnum) {
+ r = ns_skiprr(handle->_msg_ptr, handle->_eom, section, rrnum - handle->_rrnum);
+ if (r < 0) return -1;
+ handle->_msg_ptr += r;
+ handle->_rrnum = rrnum;
+ }
+ r = ns_name_uncompress(handle->_msg, handle->_eom, handle->_msg_ptr, rr->name, NS_MAXDNAME);
+ if (r < 0) return -1;
+ handle->_msg_ptr += r;
+ if (2 * NS_INT16SZ > handle->_eom - handle->_msg_ptr) goto size;
+ NS_GET16(rr->type, handle->_msg_ptr);
+ NS_GET16(rr->rr_class, handle->_msg_ptr);
+ if (section != ns_s_qd) {
+ if (NS_INT32SZ + NS_INT16SZ > handle->_eom - handle->_msg_ptr) goto size;
+ NS_GET32(rr->ttl, handle->_msg_ptr);
+ NS_GET16(rr->rdlength, handle->_msg_ptr);
+ if (rr->rdlength > handle->_eom - handle->_msg_ptr) goto size;
+ rr->rdata = handle->_msg_ptr;
+ handle->_msg_ptr += rr->rdlength;
+ } else {
+ rr->ttl = 0;
+ rr->rdlength = 0;
+ rr->rdata = NULL;
+ }
+ handle->_rrnum++;
+ if (handle->_rrnum > handle->_counts[section]) {
+ handle->_sect = section + 1;
+ if (handle->_sect == ns_s_max) {
+ handle->_rrnum = -1;
+ handle->_msg_ptr = NULL;
+ } else {
+ handle->_rrnum = 0;
+ }
+ }
+ return 0;
+bad:
+ errno = ENODEV;
+ return -1;
+size:
+ errno = EMSGSIZE;
+ return -1;
+}
+
+int ns_name_uncompress(const unsigned char *msg, const unsigned char *eom,
+ const unsigned char *src, char *dst, size_t dstsiz)
+{
+ int r;
+ r = dn_expand(msg, eom, src, dst, dstsiz);
+ if (r < 0) errno = EMSGSIZE;
+ return r;
+}
+