[SR-Dev] git:ser_core_cvs: dns: minor fixes

Module: sip-router Branch: ser_core_cvs Commit: 6082a27973483a25ffe2a091b3b1f2b261361aba URL: http://git.sip-router.org/cgi-bin/gitweb.cgi/sip-router/?a=commit;h=6082a27… Author: Andrei Pelinescu-Onciul <andrei(a)iptel.org> Committer: Andrei Pelinescu-Onciul <andrei(a)iptel.org> Date: Tue Mar 31 17:06:00 2009 +0000 dns: minor fixes - some dns record parsers need only the record end for their internal overflow checks, while others need also the message end (anything that expands compressed strings). --- resolve.c | 30 +++++++++++++++++------------- 1 files changed, 17 insertions(+), 13 deletions(-) diff --git a/resolve.c b/resolve.c index 9f55f3d..3504f0d 100644 --- a/resolve.c +++ b/resolve.c @@ -230,6 +230,7 @@ unsigned char* dns_skipname(unsigned char* p, unsigned char* end) /* parses the srv record into a srv_rdata structure * msg - pointer to the dns message * end - pointer to the end of the message + * eor - pointer to the end of the record/rdata * rdata - pointer to the rdata part of the srv answer * returns 0 on error, or a dyn. alloc'ed srv_rdata structure */ /* SRV rdata format: @@ -248,6 +249,7 @@ unsigned char* dns_skipname(unsigned char* p, unsigned char* end) * +----------------+ */ struct srv_rdata* dns_srv_parser( unsigned char* msg, unsigned char* end, + unsigned char* eor, unsigned char* rdata) { struct srv_rdata* srv; @@ -258,7 +260,7 @@ struct srv_rdata* dns_srv_parser( unsigned char* msg, unsigned char* end, char name[MAX_DNS_NAME]; srv=0; - if ((rdata+6+1)>end) goto error; + if ((rdata+6+1)>eor) goto error; memcpy((void*)&priority, rdata, 2); memcpy((void*)&weight, rdata+2, 2); @@ -292,6 +294,7 @@ error: /* parses the naptr record into a naptr_rdata structure * msg - pointer to the dns message * end - pointer to the end of the message + * eor - pointer to the end of the record/rdata * rdata - pointer to the rdata part of the naptr answer * returns 0 on error, or a dyn. alloc'ed naptr_rdata structure */ /* NAPTR rdata format: @@ -316,7 +319,8 @@ error: * +----------------+ */ struct naptr_rdata* dns_naptr_parser( unsigned char* msg, unsigned char* end, - unsigned char* rdata) + unsigned char* eor, + unsigned char* rdata) { struct naptr_rdata* naptr; unsigned char* flags; @@ -331,20 +335,20 @@ struct naptr_rdata* dns_naptr_parser( unsigned char* msg, unsigned char* end, char repl[MAX_DNS_NAME]; naptr = 0; - if ((rdata + 7 + 1)>end) goto error; + if ((rdata + 7 + 1)>eor) goto error; memcpy((void*)&order, rdata, 2); memcpy((void*)&pref, rdata + 2, 2); flags_len = rdata[4]; - if ((rdata + 7 + 1 + flags_len) > end) + if ((rdata + 7 + 1 + flags_len) > eor) goto error; flags=rdata+5; services_len = rdata[5 + flags_len]; - if ((rdata + 7 + 1 + flags_len + services_len) > end) + if ((rdata + 7 + 1 + flags_len + services_len) > eor) goto error; services=rdata + 6 + flags_len; regexp_len = rdata[6 + flags_len + services_len]; - if ((rdata + 7 +1 + flags_len + services_len + regexp_len) > end) + if ((rdata + 7 +1 + flags_len + services_len + regexp_len) > eor) goto error; regexp=rdata + 7 + flags_len + services_len; rdata = rdata + 7 + flags_len + services_len + regexp_len; @@ -418,11 +422,11 @@ error: /* parses an A record rdata into an a_rdata structure * returns 0 on error or a dyn. alloc'ed a_rdata struct */ -struct a_rdata* dns_a_parser(unsigned char* rdata, unsigned char* end) +struct a_rdata* dns_a_parser(unsigned char* rdata, unsigned char* eor) { struct a_rdata* a; - if (rdata+4>end) goto error; + if (rdata+4>eor) goto error; a=(struct a_rdata*)local_malloc(sizeof(struct a_rdata)); if (a==0){ LOG(L_ERR, "ERROR: dns_a_parser: out of memory\n"); @@ -438,11 +442,11 @@ error: /* parses an AAAA (ipv6) record rdata into an aaaa_rdata structure * returns 0 on error or a dyn. alloc'ed aaaa_rdata struct */ -struct aaaa_rdata* dns_aaaa_parser(unsigned char* rdata, unsigned char* end) +struct aaaa_rdata* dns_aaaa_parser(unsigned char* rdata, unsigned char* eor) { struct aaaa_rdata* aaaa; - if (rdata+16>end) goto error; + if (rdata+16>eor) goto error; aaaa=(struct aaaa_rdata*)local_malloc(sizeof(struct aaaa_rdata)); if (aaaa==0){ LOG(L_ERR, "ERROR: dns_aaaa_parser: out of memory\n"); @@ -641,7 +645,7 @@ again: } switch(rtype){ case T_SRV: - srv_rd= dns_srv_parser(buff.buff, rd_end, p); + srv_rd= dns_srv_parser(buff.buff, end, rd_end, p); rd->rdata=(void*)srv_rd; if (unlikely(srv_rd==0)) goto error_parse; @@ -678,13 +682,13 @@ again: last=&(rd->next); break; case T_CNAME: - rd->rdata=(void*) dns_cname_parser(buff.buff, rd_end, p); + rd->rdata=(void*) dns_cname_parser(buff.buff, end, p); if(unlikely(rd->rdata==0)) goto error_parse; *last=rd; last=&(rd->next); break; case T_NAPTR: - rd->rdata=(void*) dns_naptr_parser(buff.buff, rd_end, p); + rd->rdata=(void*)dns_naptr_parser(buff.buff, end, rd_end, p); if(unlikely(rd->rdata==0)) goto error_parse; *last=rd; last=&(rd->next);