From f4c3850ea335545e297504941dc8c7a8f1c83358 Mon Sep 17 00:00:00 2001 From: David Kalnischkies Date: Sun, 18 Aug 2013 23:17:05 +0200 Subject: add a simple container for HashStrings APT supports more than just one HashString and even allows to enforce the usage of a specific hash. This class is intended to help with storage and passing around of the HashStrings. Git-Dch: Ignore --- apt-pkg/contrib/hashes.cc | 118 ++++++++++++++++++++++++++++++++++++++++------ apt-pkg/contrib/hashes.h | 85 ++++++++++++++++++++++++++++++++- 2 files changed, 187 insertions(+), 16 deletions(-) (limited to 'apt-pkg') diff --git a/apt-pkg/contrib/hashes.cc b/apt-pkg/contrib/hashes.cc index 15f83615d..bb11a3fca 100644 --- a/apt-pkg/contrib/hashes.cc +++ b/apt-pkg/contrib/hashes.cc @@ -27,7 +27,7 @@ #include /*}}}*/ -const char* HashString::_SupportedHashes[] = +const char * HashString::_SupportedHashes[] = { "SHA512", "SHA256", "SHA1", "MD5Sum", NULL }; @@ -42,11 +42,16 @@ HashString::HashString(std::string Type, std::string Hash) : Type(Type), Hash(Ha HashString::HashString(std::string StringedHash) /*{{{*/ { - // legacy: md5sum without "MD5Sum:" prefix - if (StringedHash.find(":") == std::string::npos && StringedHash.size() == 32) + if (StringedHash.find(":") == std::string::npos) { - Type = "MD5Sum"; - Hash = StringedHash; + // legacy: md5sum without "MD5Sum:" prefix + if (StringedHash.size() == 32) + { + Type = "MD5Sum"; + Hash = StringedHash; + } + if(_config->FindB("Debug::Hashes",false) == true) + std::clog << "HashString(string): invalid StringedHash " << StringedHash << std::endl; return; } std::string::size_type pos = StringedHash.find(":"); @@ -82,25 +87,25 @@ std::string HashString::GetHashForFile(std::string filename) const /*{{{*/ std::string fileHash; FileFd Fd(filename, FileFd::ReadOnly); - if(Type == "MD5Sum") + if(strcasecmp(Type.c_str(), "MD5Sum") == 0) { MD5Summation MD5; MD5.AddFD(Fd); fileHash = (std::string)MD5.Result(); } - else if (Type == "SHA1") + else if (strcasecmp(Type.c_str(), "SHA1") == 0) { SHA1Summation SHA1; SHA1.AddFD(Fd); fileHash = (std::string)SHA1.Result(); } - else if (Type == "SHA256") + else if (strcasecmp(Type.c_str(), "SHA256") == 0) { SHA256Summation SHA256; SHA256.AddFD(Fd); fileHash = (std::string)SHA256.Result(); } - else if (Type == "SHA512") + else if (strcasecmp(Type.c_str(), "SHA512") == 0) { SHA512Summation SHA512; SHA512.AddFD(Fd); @@ -111,20 +116,105 @@ std::string HashString::GetHashForFile(std::string filename) const /*{{{*/ return fileHash; } /*}}}*/ -const char** HashString::SupportedHashes() +const char** HashString::SupportedHashes() /*{{{*/ { return _SupportedHashes; } - -APT_PURE bool HashString::empty() const + /*}}}*/ +APT_PURE bool HashString::empty() const /*{{{*/ { return (Type.empty() || Hash.empty()); } + /*}}}*/ +std::string HashString::toStr() const /*{{{*/ +{ + return Type + ":" + Hash; +} + /*}}}*/ +APT_PURE bool HashString::operator==(HashString const &other) const /*{{{*/ +{ + return (strcasecmp(Type.c_str(), other.Type.c_str()) == 0 && Hash == other.Hash); +} +APT_PURE bool HashString::operator!=(HashString const &other) const +{ + return !(*this == other); +} + /*}}}*/ + +HashString const * HashStringList::find(char const * const type) const /*{{{*/ +{ + if (type == NULL || type[0] == '\0') + { + std::string forcedType = _config->Find("Acquire::ForceHash", ""); + if (forcedType.empty() == false) + return find(forcedType.c_str()); + for (char const * const * t = HashString::SupportedHashes(); *t != NULL; ++t) + for (std::vector::const_iterator hs = list.begin(); hs != list.end(); ++hs) + if (strcasecmp(hs->HashType().c_str(), *t) == 0) + return &*hs; + return NULL; + } + for (std::vector::const_iterator hs = list.begin(); hs != list.end(); ++hs) + if (strcasecmp(hs->HashType().c_str(), type) == 0) + return &*hs; + return NULL; +} + /*}}}*/ +bool HashStringList::supported(char const * const type) /*{{{*/ +{ + for (char const * const * t = HashString::SupportedHashes(); *t != NULL; ++t) + if (strcasecmp(*t, type) == 0) + return true; + return false; +} + /*}}}*/ +bool HashStringList::push_back(const HashString &hashString) /*{{{*/ +{ + if (hashString.HashType().empty() == true || + hashString.HashValue().empty() == true || + supported(hashString.HashType().c_str()) == false) + return false; + + // ensure that each type is added only once + HashString const * const hs = find(hashString.HashType().c_str()); + if (hs != NULL) + return *hs == hashString; -std::string HashString::toStr() const + list.push_back(hashString); + return true; +} + /*}}}*/ +bool HashStringList::VerifyFile(std::string filename) const /*{{{*/ { - return Type + std::string(":") + Hash; + if (list.empty() == true) + return false; + HashString const * const hs = find(NULL); + if (hs == NULL || hs->VerifyFile(filename) == false) + return false; + return true; } + /*}}}*/ +bool HashStringList::operator==(HashStringList const &other) const /*{{{*/ +{ + short matches = 0; + for (const_iterator hs = begin(); hs != end(); ++hs) + { + HashString const * const ohs = other.find(hs->HashType()); + if (ohs == NULL) + continue; + if (*hs != *ohs) + return false; + ++matches; + } + if (matches == 0) + return false; + return true; +} +bool HashStringList::operator!=(HashStringList const &other) const +{ + return !(*this == other); +} + /*}}}*/ // Hashes::AddFD - Add the contents of the FD /*{{{*/ // --------------------------------------------------------------------- diff --git a/apt-pkg/contrib/hashes.h b/apt-pkg/contrib/hashes.h index 7a62f8a8f..490282209 100644 --- a/apt-pkg/contrib/hashes.h +++ b/apt-pkg/contrib/hashes.h @@ -17,6 +17,7 @@ #include #include #include +#include #include #include @@ -41,7 +42,7 @@ class HashString protected: std::string Type; std::string Hash; - static const char* _SupportedHashes[10]; + static const char * _SupportedHashes[10]; // internal helper std::string GetHashForFile(std::string filename) const; @@ -52,7 +53,8 @@ class HashString HashString(); // get hash type used - std::string HashType() { return Type; }; + std::string HashType() const { return Type; }; + std::string HashValue() const { return Hash; }; // verify the given filename against the currently loaded hash bool VerifyFile(std::string filename) const; @@ -64,11 +66,90 @@ class HashString // helper std::string toStr() const; // convert to str as "type:hash" bool empty() const; + bool operator==(HashString const &other) const; + bool operator!=(HashString const &other) const; // return the list of hashes we support static APT_CONST const char** SupportedHashes(); }; +class HashStringList +{ + public: + /** find best hash if no specific one is requested + * + * @param type of the checksum to return, can be \b NULL + * @return If type is \b NULL (or the empty string) it will + * return the 'best' hash; otherwise the hash which was + * specifically requested. If no hash is found \b NULL will be returned. + */ + HashString const * find(char const * const type) const; + HashString const * find(std::string const &type) const { return find(type.c_str()); } + /** check if the given hash type is supported + * + * @param type to check + * @return true if supported, otherwise false + */ + static APT_PURE bool supported(char const * const type); + /** add the given #HashString to the list + * + * @param hashString to add + * @return true if the hash is added because it is supported and + * not already a different hash of the same type included, otherwise false + */ + bool push_back(const HashString &hashString); + /** @return size of the list of HashStrings */ + size_t size() const { return list.size(); } + + /** take the 'best' hash and verify file with it + * + * @param filename to verify + * @return true if the file matches the hashsum, otherwise false + */ + bool VerifyFile(std::string filename) const; + + /** is the list empty ? + * + * @return \b true if the list is empty, otherwise \b false + */ + bool empty() const { return list.empty(); } + + typedef std::vector::const_iterator const_iterator; + + /** iterator to the first element */ + const_iterator begin() const { return list.begin(); } + + /** iterator to the end element */ + const_iterator end() const { return list.end(); } + + /** start fresh with a clear list */ + void clear() { list.clear(); } + + /** compare two HashStringList for similarity. + * + * Two lists are similar if at least one hashtype is in both lists + * and the hashsum matches. All hashes are checked, if one doesn't + * match false is returned regardless of how many matched before. + */ + bool operator==(HashStringList const &other) const; + bool operator!=(HashStringList const &other) const; + + HashStringList() {} + + // simplifying API-compatibility constructors + HashStringList(std::string const &hash) { + if (hash.empty() == false) + list.push_back(HashString(hash)); + } + HashStringList(char const * const hash) { + if (hash != NULL && hash[0] != '\0') + list.push_back(HashString(hash)); + } + + private: + std::vector list; +}; + class Hashes { public: -- cgit v1.2.3