From e45372c163ef6a942f7856acf87173c8a79c3d85 Mon Sep 17 00:00:00 2001 From: Ian Jackson Date: Sun, 26 Oct 2014 11:06:09 +0000 Subject: [PATCH] resolv.conf option parsing: Fix word separation `nextword' does not nul-terminate the words it returns. So the strcmps in ccf_options are wrong. Fix this as follows: * Abolish most uses of l in favour of a pointer variable endword. * Have OPTION_IS and OPTION_STARTS update word, and endword, so that it is convenient to use them for option values, etc. * Save the whole option in new variables opt and optend for reporting and to assist the `adns_af:' loop. * Use OPTION_IS, OPTION_STARTS and memchr, rather than strcmp, ad-hoc memcmp, and strcspn. Signed-off-by: Ian Jackson --- src/setup.c | 43 +++++++++++++++++++++++-------------------- 1 file changed, 23 insertions(+), 20 deletions(-) diff --git a/src/setup.c b/src/setup.c index c5ffed6..2de3eaa 100644 --- a/src/setup.c +++ b/src/setup.c @@ -260,64 +260,67 @@ static void ccf_sortlist(adns_state ads, const char *fn, static void ccf_options(adns_state ads, const char *fn, int lno, const char *buf) { - const char *word, *rhs; + const char *opt, *word, *endword, *endopt; char *ep; unsigned long v; - int i,l; + int l; if (!buf) return; -#define OPTION__IS(s,op) (l op (sizeof(s)-1) && !memcmp(word,s,(sizeof(s)-1))) +#define OPTION__IS(s,op) ((endword-word) op (sizeof(s)-1) && \ + !memcmp(word,s,(sizeof(s)-1))) #define OPTION_IS(s) (OPTION__IS(s,==)) -#define OPTION_STARTS(s) (OPTION__IS(s,>=) ? ((rhs=word+sizeof(s)-1)) : 0) +#define OPTION_STARTS(s) (OPTION__IS(s,>=) ? ((word+=sizeof(s)-1)) : 0) while (nextword(&buf,&word,&l)) { + opt=word; + endopt=endword=word+l; if (OPTION_IS("debug")) { ads->iflags |= adns_if_debug; continue; } if (OPTION_STARTS("ndots:")) { - v= strtoul(rhs,&ep,10); - if (ep==rhs || ep != word+l || v > INT_MAX) { + v= strtoul(word,&ep,10); + if (ep==word || ep != endword || v > INT_MAX) { configparseerr(ads,fn,lno,"option `%.*s' malformed" - " or has bad value",l,word); + " or has bad value",l,opt); continue; } ads->searchndots= v; continue; } if (OPTION_STARTS("adns_checkc:")) { - if (!strcmp(rhs,"none")) { + if (OPTION_IS("none")) { ads->iflags &= ~adns_if_checkc_freq; ads->iflags |= adns_if_checkc_entex; - } else if (!strcmp(rhs,"entex")) { + } else if (OPTION_IS("entex")) { ads->iflags &= ~adns_if_checkc_freq; ads->iflags |= adns_if_checkc_entex; - } else if (!strcmp(rhs,"freq")) { + } else if (OPTION_IS("freq")) { ads->iflags |= adns_if_checkc_freq; } else { configparseerr(ads,fn,lno, "option adns_checkc has bad value `%s' " - "(must be none, entex or freq", rhs); + "(must be none, entex or freq", word); } continue; } if (OPTION_STARTS("adns_af:")) { - word= rhs; ads->iflags &= ~adns_if_afmask; - if (strcmp(word,"any")) for (;;) { - i= strcspn(word,","); - if (i>=4 && !memcmp(word,"ipv4",4)) + if (!OPTION_IS("any")) for (;;) { + const char *comma= memchr(word,',',endopt-word); + endword=comma?comma:endopt; + if (OPTION_IS("ipv4")) ads->iflags |= adns_if_permit_ipv4; - else if (i>=4 && !memcmp(word,"ipv6",4)) + else if (OPTION_IS("ipv6")) ads->iflags |= adns_if_permit_ipv6; else { configparseerr(ads,fn,lno, "option adns_af has bad value `%.*s' " "(must be `any' or list {`ipv4',`ipv6'},...)", - i, word); + (int)(endword-word), word); break; } - if (!word[i]) break; - word= word + i + 1; + if (!comma) break; + word= comma+1; } continue; } @@ -338,7 +341,7 @@ static void ccf_options(adns_state ads, const char *fn, OPTION_IS("edns0")) continue; if (ads->config_report_unknown) - adns__diag(ads,-1,0,"%s:%d: unknown option `%.*s'", fn,lno, l,word); + adns__diag(ads,-1,0,"%s:%d: unknown option `%.*s'", fn,lno, l,opt); } #undef OPTION__IS -- 2.30.2