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Diffstat (limited to '')
| -rw-r--r-- | apt-pkg/acquire-method.cc | 600 |
1 files changed, 600 insertions, 0 deletions
diff --git a/apt-pkg/acquire-method.cc b/apt-pkg/acquire-method.cc new file mode 100644 index 0000000..0895825 --- /dev/null +++ b/apt-pkg/acquire-method.cc @@ -0,0 +1,600 @@ +// -*- mode: cpp; mode: fold -*- +// Description /*{{{*/ +/* ###################################################################### + + Acquire Method + + This is a skeleton class that implements most of the functionality + of a method and some useful functions to make method implementation + simpler. The methods all derive this and specialize it. The most + complex implementation is the http method which needs to provide + pipelining, it runs the message engine at the same time it is + downloading files.. + + ##################################################################### */ + /*}}}*/ +// Include Files /*{{{*/ +#include <config.h> + +#include <apt-pkg/acquire-method.h> +#include <apt-pkg/configuration.h> +#include <apt-pkg/error.h> +#include <apt-pkg/fileutl.h> +#include <apt-pkg/hashes.h> +#include <apt-pkg/strutl.h> + +#include <algorithm> +#include <iostream> +#include <iterator> +#include <sstream> +#include <string> +#include <vector> +#include <stdarg.h> +#include <stdio.h> +#include <stdlib.h> +#include <string.h> +#include <unistd.h> + /*}}}*/ + +using namespace std; + +// poor mans unordered_map::try_emplace for C++11 as it is a C++17 feature /*{{{*/ +template <typename Arg> +static void try_emplace(std::unordered_map<std::string, std::string> &fields, std::string &&name, Arg &&value) +{ + if (fields.find(name) == fields.end()) + fields.emplace(std::move(name), std::forward<Arg>(value)); +} + /*}}}*/ + +// AcqMethod::pkgAcqMethod - Constructor /*{{{*/ +// --------------------------------------------------------------------- +/* This constructs the initialization text */ +pkgAcqMethod::pkgAcqMethod(const char *Ver,unsigned long Flags) +{ + std::unordered_map<std::string, std::string> fields; + try_emplace(fields, "Version", Ver); + if ((Flags & SingleInstance) == SingleInstance) + try_emplace(fields, "Single-Instance", "true"); + + if ((Flags & Pipeline) == Pipeline) + try_emplace(fields, "Pipeline", "true"); + + if ((Flags & SendConfig) == SendConfig) + try_emplace(fields, "Send-Config", "true"); + + if ((Flags & LocalOnly) == LocalOnly) + try_emplace(fields, "Local-Only", "true"); + + if ((Flags & NeedsCleanup) == NeedsCleanup) + try_emplace(fields, "Needs-Cleanup", "true"); + + if ((Flags & Removable) == Removable) + try_emplace(fields, "Removable", "true"); + + if ((Flags & AuxRequests) == AuxRequests) + try_emplace(fields, "AuxRequests", "true"); + + if ((Flags & SendURIEncoded) == SendURIEncoded) + try_emplace(fields, "Send-URI-Encoded", "true"); + + SendMessage("100 Capabilities", std::move(fields)); + + SetNonBlock(STDIN_FILENO,true); + + Queue = 0; + QueueBack = 0; +} + /*}}}*/ +void pkgAcqMethod::SendMessage(std::string const &header, std::unordered_map<std::string, std::string> &&fields) /*{{{*/ +{ + auto CheckKey = [](std::string const &str) { + // Space, hyphen-minus, and alphanum are allowed for keys/headers. + return str.find_first_not_of(" -0123456789ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz") == std::string::npos; + }; + + auto CheckValue = [](std::string const &str) { + return std::all_of(str.begin(), str.end(), [](unsigned char c) -> bool { + return c > 127 // unicode + || (c > 31 && c < 127) // printable chars + || c == '\n' || c == '\t'; // special whitespace + }); + }; + + auto Error = [this]() { + _error->Error("SECURITY: Message contains control characters, rejecting."); + _error->DumpErrors(); + SendMessage("400 URI Failure", {{"URI", "<UNKNOWN>"}, {"Message", "SECURITY: Message contains control characters, rejecting."}}); + abort(); + }; + + if (!CheckKey(header)) + return Error(); + + for (auto const &f : fields) + { + if (!CheckKey(f.first)) + return Error(); + if (!CheckValue(f.second)) + return Error(); + } + + std::cout << header << '\n'; + for (auto const &f : fields) + { + if (f.second.empty()) + continue; + std::cout << f.first << ": "; + auto const lines = VectorizeString(f.second, '\n'); + if (likely(lines.empty() == false)) + { + std::copy(lines.begin(), std::prev(lines.end()), std::ostream_iterator<std::string>(std::cout, "\n ")); + std::cout << *lines.rbegin(); + } + std::cout << '\n'; + } + std::cout << '\n' + << std::flush; +} + /*}}}*/ +// AcqMethod::Fail - A fetch has failed /*{{{*/ +// --------------------------------------------------------------------- +/* */ +void pkgAcqMethod::Fail(bool Transient) +{ + + Fail("", Transient); +} + /*}}}*/ +// AcqMethod::Fail - A fetch has failed /*{{{*/ +void pkgAcqMethod::Fail(string Err, bool Transient) +{ + + if (not _error->empty()) + { + while (not _error->empty()) + { + std::string msg; + if (_error->PopMessage(msg)) + { + if (not Err.empty()) + Err.append("\n"); + Err.append(msg); + } + } + } + if (Err.empty()) + Err = "Undetermined Error"; + + // Strip out junk from the error messages + std::transform(Err.begin(), Err.end(), Err.begin(), [](char const c) { + if (c == '\r' || c == '\n') + return ' '; + return c; + }); + if (IP.empty() == false && _config->FindB("Acquire::Failure::ShowIP", true) == true) + Err.append(" ").append(IP); + + std::unordered_map<std::string, std::string> fields; + if (Queue != nullptr) + try_emplace(fields, "URI", Queue->Uri); + else + try_emplace(fields, "URI", "<UNKNOWN>"); + try_emplace(fields, "Message", Err); + + if(FailReason.empty() == false) + try_emplace(fields, "FailReason", FailReason); + if (UsedMirror.empty() == false) + try_emplace(fields, "UsedMirror", UsedMirror); + if (Transient == true) + try_emplace(fields, "Transient-Failure", "true"); + + SendMessage("400 URI Failure", std::move(fields)); + + if (Queue != nullptr) + Dequeue(); +} + /*}}}*/ +// AcqMethod::DropPrivsOrDie - Drop privileges or die /*{{{*/ +// --------------------------------------------------------------------- +/* */ +void pkgAcqMethod::DropPrivsOrDie() +{ + if (!DropPrivileges()) { + Fail(false); + exit(112); /* call the european emergency number */ + } +} + + /*}}}*/ +// AcqMethod::URIStart - Indicate a download is starting /*{{{*/ +void pkgAcqMethod::URIStart(FetchResult &Res) +{ + if (Queue == 0) + abort(); + + std::unordered_map<std::string, std::string> fields; + try_emplace(fields, "URI", Queue->Uri); + if (Res.Size != 0) + try_emplace(fields, "Size", std::to_string(Res.Size)); + if (Res.LastModified != 0) + try_emplace(fields, "Last-Modified", TimeRFC1123(Res.LastModified, true)); + if (Res.ResumePoint != 0) + try_emplace(fields, "Resume-Point", std::to_string(Res.ResumePoint)); + if (UsedMirror.empty() == false) + try_emplace(fields, "UsedMirror", UsedMirror); + + SendMessage("200 URI Start", std::move(fields)); +} + /*}}}*/ +// AcqMethod::URIDone - A URI is finished /*{{{*/ +static void printHashStringList(std::unordered_map<std::string, std::string> &fields, std::string const &Prefix, HashStringList const &list) +{ + for (auto const &hash : list) + { + // very old compatibility name for MD5Sum + if (hash.HashType() == "MD5Sum") + try_emplace(fields, Prefix + "MD5-Hash", hash.HashValue()); + try_emplace(fields, Prefix + hash.HashType() + "-Hash", hash.HashValue()); + } +} +void pkgAcqMethod::URIDone(FetchResult &Res, FetchResult *Alt) +{ + if (Queue == 0) + abort(); + + std::unordered_map<std::string, std::string> fields; + try_emplace(fields, "URI", Queue->Uri); + if (Res.Filename.empty() == false) + try_emplace(fields, "Filename", Res.Filename); + if (Res.Size != 0) + try_emplace(fields, "Size", std::to_string(Res.Size)); + if (Res.LastModified != 0) + try_emplace(fields, "Last-Modified", TimeRFC1123(Res.LastModified, true)); + printHashStringList(fields, "", Res.Hashes); + + if (UsedMirror.empty() == false) + try_emplace(fields, "UsedMirror", UsedMirror); + if (Res.GPGVOutput.empty() == false) + { + std::ostringstream os; + std::copy(Res.GPGVOutput.begin(), Res.GPGVOutput.end() - 1, std::ostream_iterator<std::string>(os, "\n")); + os << *Res.GPGVOutput.rbegin(); + try_emplace(fields, "GPGVOutput", os.str()); + } + if (Res.ResumePoint != 0) + try_emplace(fields, "Resume-Point", std::to_string(Res.ResumePoint)); + if (Res.IMSHit == true) + try_emplace(fields, "IMS-Hit", "true"); + + if (Alt != nullptr) + { + if (Alt->Filename.empty() == false) + try_emplace(fields, "Alt-Filename", Alt->Filename); + if (Alt->Size != 0) + try_emplace(fields, "Alt-Size", std::to_string(Alt->Size)); + if (Alt->LastModified != 0) + try_emplace(fields, "Alt-Last-Modified", TimeRFC1123(Alt->LastModified, true)); + if (Alt->IMSHit == true) + try_emplace(fields, "Alt-IMS-Hit", "true"); + printHashStringList(fields, "Alt-", Alt->Hashes); + } + + SendMessage("201 URI Done", std::move(fields)); + Dequeue(); +} + /*}}}*/ +// AcqMethod::MediaFail - Synchronous request for new media /*{{{*/ +// --------------------------------------------------------------------- +/* This sends a 403 Media Failure message to the APT and waits for it + to be ackd */ +bool pkgAcqMethod::MediaFail(string Required,string Drive) +{ + fprintf(stdout, "403 Media Failure\nMedia: %s\nDrive: %s\n", + Required.c_str(),Drive.c_str()); + std::cout << "\n" << std::flush; + + vector<string> MyMessages; + + /* Here we read messages until we find a 603, each non 603 message is + appended to the main message list for later processing */ + while (1) + { + if (WaitFd(STDIN_FILENO) == false) + return false; + + if (ReadMessages(STDIN_FILENO,MyMessages) == false) + return false; + + string Message = MyMessages.front(); + MyMessages.erase(MyMessages.begin()); + + // Fetch the message number + char *End; + int Number = strtol(Message.c_str(),&End,10); + if (End == Message.c_str()) + { + cerr << "Malformed message!" << endl; + exit(100); + } + + // Change ack + if (Number == 603) + { + while (MyMessages.empty() == false) + { + Messages.push_back(MyMessages.front()); + MyMessages.erase(MyMessages.begin()); + } + + return !StringToBool(LookupTag(Message,"Failed"),false); + } + + Messages.push_back(Message); + } +} + /*}}}*/ +// AcqMethod::Configuration - Handle the configuration message /*{{{*/ +// --------------------------------------------------------------------- +/* This parses each configuration entry and puts it into the _config + Configuration class. */ +bool pkgAcqMethod::Configuration(string Message) +{ + ::Configuration &Cnf = *_config; + + const char *I = Message.c_str(); + const char *MsgEnd = I + Message.length(); + + unsigned int Length = strlen("Config-Item"); + for (; I + Length < MsgEnd; I++) + { + // Not a config item + if (I[Length] != ':' || stringcasecmp(I,I+Length,"Config-Item") != 0) + continue; + + I += Length + 1; + + for (; I < MsgEnd && *I == ' '; I++); + const char *Equals = (const char*) memchr(I, '=', MsgEnd - I); + if (Equals == NULL) + return false; + const char *End = (const char*) memchr(Equals, '\n', MsgEnd - Equals); + if (End == NULL) + End = MsgEnd; + + Cnf.Set(DeQuoteString(string(I,Equals-I)), + DeQuoteString(string(Equals+1,End-Equals-1))); + I = End; + } + + return true; +} + /*}}}*/ +// AcqMethod::Run - Run the message engine /*{{{*/ +// --------------------------------------------------------------------- +/* Fetch any messages and execute them. In single mode it returns 1 if + there are no more available messages - any other result is a + fatal failure code! */ +int pkgAcqMethod::Run(bool Single) +{ + while (1) + { + // Block if the message queue is empty + if (Messages.empty() == true) + { + if (Single == false) + if (WaitFd(STDIN_FILENO) == false) + break; + if (ReadMessages(STDIN_FILENO,Messages) == false) + break; + } + + // Single mode exits if the message queue is empty + if (Single == true && Messages.empty() == true) + return -1; + + string Message = Messages.front(); + Messages.erase(Messages.begin()); + + // Fetch the message number + char *End; + int Number = strtol(Message.c_str(),&End,10); + if (End == Message.c_str()) + { + cerr << "Malformed message!" << endl; + return 100; + } + + switch (Number) + { + case 601: + if (Configuration(Message) == false) + return 100; + break; + + case 600: + { + FetchItem *Tmp = new FetchItem; + + Tmp->Uri = LookupTag(Message,"URI"); + Tmp->Proxy(LookupTag(Message, "Proxy")); + Tmp->DestFile = LookupTag(Message,"FileName"); + if (RFC1123StrToTime(LookupTag(Message,"Last-Modified"),Tmp->LastModified) == false) + Tmp->LastModified = 0; + Tmp->IndexFile = StringToBool(LookupTag(Message,"Index-File"),false); + Tmp->FailIgnore = StringToBool(LookupTag(Message,"Fail-Ignore"),false); + Tmp->ExpectedHashes = HashStringList(); + for (char const * const * t = HashString::SupportedHashes(); *t != NULL; ++t) + { + std::string tag = "Expected-"; + tag.append(*t); + std::string const hash = LookupTag(Message, tag.c_str()); + if (hash.empty() == false) + Tmp->ExpectedHashes.push_back(HashString(*t, hash)); + } + char *End; + if (Tmp->ExpectedHashes.FileSize() > 0) + Tmp->MaximumSize = Tmp->ExpectedHashes.FileSize(); + else + Tmp->MaximumSize = strtoll(LookupTag(Message, "Maximum-Size", "0").c_str(), &End, 10); + Tmp->Next = 0; + + // Append it to the list + FetchItem **I = &Queue; + for (; *I != 0; I = &(*I)->Next); + *I = Tmp; + if (QueueBack == 0) + QueueBack = Tmp; + + // Notify that this item is to be fetched. + if (URIAcquire(Message, Tmp) == false) + Fail(); + + break; + } + } + } + + Exit(); + return 0; +} + /*}}}*/ +// AcqMethod::PrintStatus - privately really send a log/status message /*{{{*/ +void pkgAcqMethod::PrintStatus(char const * const header, const char* Format, + va_list &args) const +{ + string CurrentURI = "<UNKNOWN>"; + if (Queue != 0) + CurrentURI = Queue->Uri; + if (UsedMirror.empty() == true) + fprintf(stdout, "%s\nURI: %s\nMessage: ", + header, CurrentURI.c_str()); + else + fprintf(stdout, "%s\nURI: %s\nUsedMirror: %s\nMessage: ", + header, CurrentURI.c_str(), UsedMirror.c_str()); + vfprintf(stdout,Format,args); + std::cout << "\n\n" << std::flush; +} + /*}}}*/ +// AcqMethod::Log - Send a log message /*{{{*/ +// --------------------------------------------------------------------- +/* */ +void pkgAcqMethod::Log(const char *Format,...) +{ + va_list args; + ssize_t size = 400; + std::ostringstream outstr; + while (true) { + bool ret; + va_start(args,Format); + ret = iovprintf(outstr, Format, args, size); + va_end(args); + if (ret == true) + break; + } + std::unordered_map<std::string, std::string> fields; + if (Queue != 0) + try_emplace(fields, "URI", Queue->Uri); + else + try_emplace(fields, "URI", "<UNKNOWN>"); + if (not UsedMirror.empty()) + try_emplace(fields, "UsedMirror", UsedMirror); + try_emplace(fields, "Message", outstr.str()); + SendMessage("101 Log", std::move(fields)); +} + /*}}}*/ +// AcqMethod::Status - Send a status message /*{{{*/ +// --------------------------------------------------------------------- +/* */ +void pkgAcqMethod::Status(const char *Format,...) +{ + va_list args; + ssize_t size = 400; + std::ostringstream outstr; + while (true) { + bool ret; + va_start(args,Format); + ret = iovprintf(outstr, Format, args, size); + va_end(args); + if (ret == true) + break; + } + std::unordered_map<std::string, std::string> fields; + if (Queue != 0) + try_emplace(fields, "URI", Queue->Uri); + else + try_emplace(fields, "URI", "<UNKNOWN>"); + if (not UsedMirror.empty()) + try_emplace(fields, "UsedMirror", UsedMirror); + try_emplace(fields, "Message", outstr.str()); + SendMessage("102 Status", std::move(fields)); +} + /*}}}*/ +// AcqMethod::Redirect - Send a redirect message /*{{{*/ +// --------------------------------------------------------------------- +/* This method sends the redirect message and dequeues the item as + * the worker will enqueue again later on to the right queue */ +void pkgAcqMethod::Redirect(const string &NewURI) +{ + if (NewURI.find_first_not_of(" !\"#$%&'()*+,-./0123456789:;<=>?@ABCDEFGHIJKLMNOPQRSTUVWXYZ[\\]^_`abcdefghijklmnopqrstuvwxyz{|}~") != std::string::npos) + { + _error->Error("SECURITY: URL redirect target contains control characters, rejecting."); + Fail(); + return; + } + std::unordered_map<std::string, std::string> fields; + try_emplace(fields, "URI", Queue->Uri); + try_emplace(fields, "New-URI", NewURI); + SendMessage("103 Redirect", std::move(fields)); + Dequeue(); +} + /*}}}*/ +// AcqMethod::FetchResult::FetchResult - Constructor /*{{{*/ +// --------------------------------------------------------------------- +/* */ +pkgAcqMethod::FetchResult::FetchResult() : LastModified(0), + IMSHit(false), Size(0), ResumePoint(0), d(NULL) +{ +} + /*}}}*/ +// AcqMethod::FetchResult::TakeHashes - Load hashes /*{{{*/ +// --------------------------------------------------------------------- +/* This hides the number of hashes we are supporting from the caller. + It just deals with the hash class. */ +void pkgAcqMethod::FetchResult::TakeHashes(class Hashes &Hash) +{ + Hashes = Hash.GetHashStringList(); +} + /*}}}*/ +void pkgAcqMethod::Dequeue() { /*{{{*/ + FetchItem const * const Tmp = Queue; + Queue = Queue->Next; + if (Tmp == QueueBack) + QueueBack = Queue; + delete Tmp; +} + /*}}}*/ +pkgAcqMethod::~pkgAcqMethod() {} + +struct pkgAcqMethod::FetchItem::Private +{ + std::string Proxy; +}; + +pkgAcqMethod::FetchItem::FetchItem() : Next(nullptr), DestFileFd(-1), LastModified(0), IndexFile(false), + FailIgnore(false), MaximumSize(0), d(new Private) +{} + +std::string pkgAcqMethod::FetchItem::Proxy() +{ + return d->Proxy; +} + +void pkgAcqMethod::FetchItem::Proxy(std::string const &Proxy) +{ + d->Proxy = Proxy; +} + +pkgAcqMethod::FetchItem::~FetchItem() { delete d; } + +pkgAcqMethod::FetchResult::~FetchResult() {} |