diff options
| -rw-r--r-- | apt-pkg/contrib/srvrec.cc | 93 | ||||
| -rw-r--r-- | apt-pkg/contrib/srvrec.h | 30 | ||||
| -rw-r--r-- | cmdline/apt-helper.cc | 25 | ||||
| -rw-r--r-- | cmdline/makefile | 2 |
4 files changed, 149 insertions, 1 deletions
diff --git a/apt-pkg/contrib/srvrec.cc b/apt-pkg/contrib/srvrec.cc new file mode 100644 index 000000000..d5d89fc67 --- /dev/null +++ b/apt-pkg/contrib/srvrec.cc @@ -0,0 +1,93 @@ +// -*- mode: cpp; mode: fold -*- +// Description /*{{{*/ +/* ###################################################################### + + SRV record support + + ##################################################################### */ + /*}}}*/ +#include <config.h> + +#include <netinet/in.h> +#include <arpa/nameser.h> +#include <resolv.h> + +#include <apt-pkg/error.h> +#include "srvrec.h" + +bool GetSrvRecords(std::string name, std::vector<SrvRec> &Result) +{ + unsigned char answer[PACKETSZ]; + int answer_len, compressed_name_len; + int answer_count; + + if (res_init() != 0) + return _error->Errno("res_init", "Failed to init resolver"); + + answer_len = res_query(name.c_str(), C_IN, T_SRV, answer, sizeof(answer)); + if (answer_len < (int)sizeof(HEADER)) + return _error->Warning("Not enough data from res_query (%i)", answer_len); + + // check the header + HEADER *header = (HEADER*)answer; + if (header->rcode != NOERROR) + return _error->Warning("res_query returned rcode %i", header->rcode); + answer_count = ntohs(header->ancount); + if (answer_count <= 0) + return _error->Warning("res_query returned no answers (%i) ", answer_count); + + // skip the header + compressed_name_len = dn_skipname(answer+sizeof(HEADER), answer+answer_len); + if(compressed_name_len < 0) + return _error->Warning("dn_skipname failed %i", compressed_name_len); + + // pt points to the first answer record, go over all of them now + unsigned char *pt = answer+sizeof(HEADER)+compressed_name_len+QFIXEDSZ; + while ((int)Result.size() < answer_count && pt < answer+answer_len) + { + SrvRec rec; + u_int16_t type, klass, priority, weight, port, dlen; + char buf[MAXDNAME]; + + compressed_name_len = dn_skipname(pt, answer+answer_len); + if (compressed_name_len < 0) + return _error->Warning("dn_skipname failed (2): %i", + compressed_name_len); + pt += compressed_name_len; + if (((answer+answer_len) - pt) < 16) + return _error->Warning("packet too short"); + + // extract the data out of the result buffer + #define extract_u16(target, p) target = *p++ << 8; target |= *p++; + + extract_u16(type, pt); + if(type != T_SRV) + return _error->Warning("Unexpected type excepted %x != %x", + T_SRV, type); + extract_u16(klass, pt); + if(klass != C_IN) + return _error->Warning("Unexpected class excepted %x != %x", + C_IN, klass); + pt += 4; // ttl + extract_u16(dlen, pt); + extract_u16(priority, pt); + extract_u16(weight, pt); + extract_u16(port, pt); + + #undef extract_u16 + + compressed_name_len = dn_expand(answer, answer+answer_len, pt, buf, sizeof(buf)); + if(compressed_name_len < 0) + return _error->Warning("dn_expand failed %i", compressed_name_len); + pt += compressed_name_len; + + // add it to our class + rec.priority = priority; + rec.weight = weight; + rec.port = port; + rec.target = buf; + Result.push_back(rec); + } + + return true; +} diff --git a/apt-pkg/contrib/srvrec.h b/apt-pkg/contrib/srvrec.h new file mode 100644 index 000000000..583907706 --- /dev/null +++ b/apt-pkg/contrib/srvrec.h @@ -0,0 +1,30 @@ +// -*- mode: cpp; mode: fold -*- +// Description /*{{{*/ +/* ###################################################################### + + SRV record support + + ##################################################################### */ + /*}}}*/ +#ifndef SRVREC_H +#define SRVREC_H + +#include <arpa/nameser.h> +#include <vector> +#include <string> + +class SrvRec +{ + public: + std::string target; + u_int16_t priority; + u_int16_t weight; + u_int16_t port; + + // see rfc-2782 + //int random; +}; + +bool GetSrvRecords(std::string name, std::vector<SrvRec> &Result); + +#endif diff --git a/cmdline/apt-helper.cc b/cmdline/apt-helper.cc index 2c1107d90..aeeccf06d 100644 --- a/cmdline/apt-helper.cc +++ b/cmdline/apt-helper.cc @@ -21,6 +21,7 @@ #include <apt-private/private-output.h> #include <apt-private/private-download.h> #include <apt-private/private-cmndline.h> +#include <apt-pkg/srvrec.h> #include <iostream> #include <string> @@ -53,6 +54,29 @@ static bool DoDownloadFile(CommandLine &CmdL) return true; } +static bool DoSrvLookup(CommandLine &CmdL) +{ + if (CmdL.FileSize() < 1) + return _error->Error(_("Must specifc at least one srv record")); + + std::vector<SrvRec> srv_records; + for(int i=1; CmdL.FileList[i] != NULL; i++) + { + if(GetSrvRecords(CmdL.FileList[i], srv_records) == false) + _error->Warning(_("GetSrvRec failed for %s"), CmdL.FileList[i]); + for (std::vector<SrvRec>::const_iterator I = srv_records.begin(); + I != srv_records.end(); ++I) + { + c1out << (*I).target.c_str() << " " + << (*I).priority << " " + << (*I).weight << " " + << (*I).port << " " + << std::endl; + } + } + return true; +} + static bool ShowHelp(CommandLine &) { ioprintf(std::cout,_("%s %s for %s compiled on %s %s\n"),PACKAGE,PACKAGE_VERSION, @@ -79,6 +103,7 @@ int main(int argc,const char *argv[]) /*{{{*/ { CommandLine::Dispatch Cmds[] = {{"help",&ShowHelp}, {"download-file", &DoDownloadFile}, + {"srv-lookup", &DoSrvLookup}, {0,0}}; std::vector<CommandLine::Args> Args = getCommandArgs( diff --git a/cmdline/makefile b/cmdline/makefile index c4a249cd6..a24738e63 100644 --- a/cmdline/makefile +++ b/cmdline/makefile @@ -49,7 +49,7 @@ include $(PROGRAM_H) # The apt-helper PROGRAM=apt-helper -SLIBS = -lapt-pkg -lapt-private $(INTLLIBS) +SLIBS = -lapt-pkg -lapt-private $(INTLLIBS) -lresolv LIB_MAKES = apt-pkg/makefile SOURCE = apt-helper.cc include $(PROGRAM_H) |