diff options
| -rw-r--r-- | src/modules/m_codepage.cpp | 216 |
1 files changed, 155 insertions, 61 deletions
diff --git a/src/modules/m_codepage.cpp b/src/modules/m_codepage.cpp index d59078e44..1e19fcf15 100644 --- a/src/modules/m_codepage.cpp +++ b/src/modules/m_codepage.cpp @@ -19,20 +19,101 @@ #include "inspircd.h" -typedef std::bitset<UCHAR_MAX + 1> AllowedChars; +class Codepage +{ + public: + enum AllowCharacterResult + { + // The character is allowed in a nick. + ACR_OKAY, + + // The character is never valid in a nick. + ACR_NOT_VALID, + + // The character is not valid at the front of a nick. + ACR_NOT_VALID_AT_FRONT + }; + + // The mapping of lower case characters to upper case characters. + unsigned char casemap[UCHAR_MAX + 1]; + + // Initialises the Codepage class. + Codepage() + { + for (size_t i = 0; i <= UCHAR_MAX; ++i) + casemap[i] = i; + } + + // Destroys the Codepage class. + virtual ~Codepage() = default; -namespace + // Specifies that a character is allowed. + virtual AllowCharacterResult AllowCharacter(uint32_t character, bool front) + { + if (front) + { + // Nicknames can not begin with a number as that would collide with + // a user identifier. + if (character >= '0' && character <= '9') + return ACR_NOT_VALID_AT_FRONT; + + // Nicknames can not begin with a : as it has special meaning within + // the IRC message format. + if (character == ':') + return ACR_NOT_VALID_AT_FRONT; + } + + // Nicknames can never contain NUL, CR, LF, or SPACE as they are either + // banned within an IRC message or have special meaning within the IRC + // message format. + if (!character || character == '\n' || character == '\r' || character == ' ') + return ACR_NOT_VALID; + + // The character is probably okay? + return ACR_OKAY; + } + + // Determines whether a nickname is valid. + virtual bool IsValidNick(const std::string& nick) = 0; + + // Retrieves the link data for this codepage. + virtual std::string LinkData() const = 0; + + // Maps an upper case character to a lower case character. + virtual bool Map(unsigned long upper, unsigned long lower) = 0; +}; + +class SingleByteCodepage final + : public Codepage { + private: + typedef std::bitset<UCHAR_MAX + 1> AllowedChars; + // The characters which are allowed in nicknames. AllowedChars allowedchars; // The characters which are allowed at the front of a nickname. AllowedChars allowedfrontchars; - // The mapping of lower case characters to upper case characters. - unsigned char casemap[UCHAR_MAX]; + public: + AllowCharacterResult AllowCharacter(uint32_t character, bool front) override + { + // Single byte codepage can, as their name suggests, only be one byte in size. + if (character > UCHAR_MAX) + return ACR_NOT_VALID; - bool IsValidNick(const std::string& nick) + // Check the common allowed character rules. + AllowCharacterResult result = Codepage::AllowCharacter(character, front); + if (result != ACR_OKAY) + return result; + + // The character is okay. + allowedchars.set(character); + allowedfrontchars.set(character, front); + return ACR_OKAY; + } + + bool IsValidNick(const std::string& nick) override { if (nick.empty() || nick.length() > ServerInstance->Config->Limits.MaxNick) return false; @@ -52,12 +133,46 @@ namespace return true; } -} -class ModuleCodepage + std::string LinkData() const override + { + std::stringstream linkdata; + + linkdata << "front="; + for (size_t i = 0; i < allowedfrontchars.size(); ++i) + if (allowedfrontchars[i]) + linkdata << static_cast<unsigned char>(i); + + linkdata << "&middle="; + for (size_t i = 0; i < allowedchars.size(); ++i) + if (allowedchars[i]) + linkdata << static_cast<unsigned char>(i); + + linkdata << "&map="; + for (size_t i = 0; i < sizeof(casemap); ++i) + if (casemap[i] != i) + linkdata << static_cast<unsigned char>(i) << casemap[i] << ','; + + return linkdata.str(); + } + + bool Map(unsigned long upper, unsigned long lower) override + { + if (upper > UCHAR_MAX || lower > UCHAR_MAX) + return false; + + casemap[upper] = lower; + return true; + } +}; + +class ModuleCodepage final : public Module { private: + // The currently active codepage. + std::unique_ptr<Codepage> codepage; + // The character map which was set before this module was loaded. const unsigned char* origcasemap; @@ -114,6 +229,7 @@ class ModuleCodepage public: ModuleCodepage() : Module(VF_VENDOR | VF_COMMON, "Allows the server administrator to define what characters are allowed in nicknames and how characters should be compared in a case insensitive way.") + , codepage(nullptr) , origcasemap(national_case_insensitive_map) , origcasemapname(ServerInstance->Config->CaseMapping) , origisnick(ServerInstance->IsNick) @@ -128,7 +244,8 @@ class ModuleCodepage ServerInstance->Config->CaseMapping = origcasemapname; national_case_insensitive_map = origcasemap; CheckDuplicateNick(); - CheckRehash(casemap); + if (codepage) // nullptr if ReadConfig throws on load. + CheckRehash(codepage->casemap); } void ReadConfig(ConfigStatus& status) override @@ -137,92 +254,69 @@ class ModuleCodepage if (name.empty()) throw ModuleException("<codepage:name> is a required field!"); - AllowedChars newallowedchars; - AllowedChars newallowedfrontchars; - + std::unique_ptr<Codepage> newcodepage = std::make_unique<SingleByteCodepage>(); for (const auto& [_, tag] : ServerInstance->Config->ConfTags("cpchars")) { - unsigned char begin = tag->getUInt("begin", tag->getUInt("index", 0), 1, UCHAR_MAX); + unsigned long begin = tag->getUInt("begin", tag->getUInt("index", 0)); if (!begin) throw ModuleException("<cpchars> tag without index or begin specified at " + tag->source.str()); - unsigned char end = tag->getUInt("end", begin, 1, UCHAR_MAX); + unsigned long end = tag->getUInt("end", begin); if (begin > end) throw ModuleException("<cpchars:begin> must be lower than <cpchars:end> at " + tag->source.str()); bool front = tag->getBool("front", false); - for (unsigned short pos = begin; pos <= end; ++pos) + for (unsigned long pos = begin; pos <= end; ++pos) { - if (pos == '\n' || pos == '\r' || pos == ' ') + switch (newcodepage->AllowCharacter(pos, front)) { - throw ModuleException(InspIRCd::Format("<cpchars> tag contains a forbidden character: %u at %s", - pos, tag->source.str().c_str())); - } + case Codepage::ACR_OKAY: + ServerInstance->Logs.Log(MODNAME, LOG_DEBUG, "Marked %lu (%.4s) as allowed (front: %s)", + pos, reinterpret_cast<unsigned char*>(&pos), front ? "yes" : "no"); + break; - if (front && (pos == ':' || isdigit(pos))) - { - throw ModuleException(InspIRCd::Format("<cpchars> tag contains a forbidden front character: %u at %s", - pos, tag->source.str().c_str())); - } + case Codepage::ACR_NOT_VALID: + throw ModuleException(InspIRCd::Format("<cpchars> tag contains a forbidden character: %lu at %s", + pos, tag->source.str().c_str())); - newallowedchars.set(pos); - newallowedfrontchars.set(pos, front); - ServerInstance->Logs.Log(MODNAME, LOG_DEBUG, "Marked %u (%c) as allowed (front: %s)", - pos, pos, front ? "yes" : "no"); + case Codepage::ACR_NOT_VALID_AT_FRONT: + throw ModuleException(InspIRCd::Format("<cpchars> tag contains a forbidden front character: %lu at %s", + pos, tag->source.str().c_str())); + } } } - unsigned char newcasemap[UCHAR_MAX]; - for (size_t i = 0; i < UCHAR_MAX; ++i) - newcasemap[i] = i; - for (const auto& [_, tag] : ServerInstance->Config->ConfTags("cpcase")) { - unsigned char lower = tag->getUInt("lower", 0, 1, UCHAR_MAX); + unsigned long lower = tag->getUInt("lower", 0); if (!lower) throw ModuleException("<cpcase:lower> is required at " + tag->source.str()); - unsigned char upper = tag->getUInt("upper", 0, 1, UCHAR_MAX); + unsigned long upper = tag->getUInt("upper", 0); if (!upper) throw ModuleException("<cpcase:upper> is required at " + tag->source.str()); - newcasemap[upper] = lower; - ServerInstance->Logs.Log(MODNAME, LOG_DEBUG, "Marked %u (%c) as the lower case version of %u (%c)", - lower, lower, upper, upper); - } + if (!newcodepage->Map(upper, lower)) + throw ModuleException("Malformed <cpcase> tag at " + tag->source.str()); - std::swap(allowedchars, newallowedchars); - std::swap(allowedfrontchars, newallowedfrontchars); - std::swap(casemap, newcasemap); + ServerInstance->Logs.Log(MODNAME, LOG_DEBUG, "Marked %lu (%.4s) as the lower case version of %lu (%.4s)", + lower, reinterpret_cast<unsigned char*>(&lower), upper, reinterpret_cast<unsigned char*>(&upper)); + } - ServerInstance->IsNick = &IsValidNick; + std::swap(codepage, newcodepage); + ServerInstance->IsNick = [this](const std::string& nick) { return codepage->IsValidNick(nick); }; CheckInvalidNick(); ServerInstance->Config->CaseMapping = name; - national_case_insensitive_map = casemap; - CheckRehash(newcasemap); + national_case_insensitive_map = codepage->casemap; + if (newcodepage) // nullptr on first read. + CheckRehash(newcodepage->casemap); } void GetLinkData(std::string& data) override { - std::stringstream linkdata; - - linkdata << "front="; - for (size_t i = 0; i < allowedfrontchars.size(); ++i) - if (allowedfrontchars[i]) - linkdata << static_cast<unsigned char>(i); - - linkdata << "&middle="; - for (size_t i = 0; i < allowedchars.size(); ++i) - if (allowedchars[i]) - linkdata << static_cast<unsigned char>(i); - - linkdata << "&map="; - for (size_t i = 0; i < sizeof(casemap); ++i) - if (casemap[i] != i) - linkdata << static_cast<unsigned char>(i) << casemap[i] << ','; - - data = linkdata.str(); + data.assign(codepage ? codepage->LinkData() : ""); } }; + MODULE_INIT(ModuleCodepage) |