[apt.git] / methods / gpgv.cc

#include <apt-pkg/error.h>
#include <apt-pkg/acquire-method.h>
#include <apt-pkg/strutl.h>
#include <apti18n.h>

#include <sys/stat.h>
#include <unistd.h>
#include <utime.h>
#include <stdio.h>
#include <fcntl.h>
#include <errno.h>
#include <sys/wait.h>
#include <iostream>

#define GNUPGPREFIX "[GNUPG:]"
#define GNUPGBADSIG "[GNUPG:] BADSIG"
#define GNUPGNOPUBKEY "[GNUPG:] NO_PUBKEY"
#define GNUPGVALIDSIG "[GNUPG:] VALIDSIG"

class GPGVMethod : public pkgAcqMethod
{
   private:
   const char *VerifyGetSigners(const char *file, const char *outfile,
				vector<string> &GoodSigners, vector<string> &BadSigners,
				vector<string> &NoPubKeySigners);
   
   protected:
   virtual bool Fetch(FetchItem *Itm);
   
   public:
   
   GPGVMethod() : pkgAcqMethod("1.0",SingleInstance | SendConfig) {};
};

const char *GPGVMethod::VerifyGetSigners(const char *file, const char *outfile,
					 vector<string> &GoodSigners,
					 vector<string> &BadSigners,
					 vector<string> &NoPubKeySigners)
{
   if (_config->FindB("Debug::Acquire::gpgv", false))
   {
      std::cerr << "inside VerifyGetSigners" << std::endl;
   }
   pid_t pid;
   int fd[2];
   FILE *pipein;
   int status;
   struct stat buff;
   string gpgvpath = _config->Find("Dir::Bin::gpg", "/usr/bin/gpgv");
   string pubringpath = _config->Find("APT::GPGV::TrustedKeyring", "/etc/apt/trusted.gpg");
   if (_config->FindB("Debug::Acquire::gpgv", false))
   {
      std::cerr << "gpgv path: " << gpgvpath << std::endl;
      std::cerr << "Keyring path: " << pubringpath << std::endl;
   }

   if (stat(pubringpath.c_str(), &buff) != 0)
      return (string("Couldn't access keyring: ") + strerror(errno)).c_str();

   if (pipe(fd) < 0)
   {
      return "Couldn't create pipe";
   }

   pid = fork();
   if (pid < 0)
   {
      return (string("Couldn't spawn new process") + strerror(errno)).c_str();
   }
   else if (pid == 0)
   {
      const char *Args[400];
      unsigned int i = 0;

      Args[i++] = gpgvpath.c_str();
      Args[i++] = "--status-fd";
      Args[i++] = "3";
      Args[i++] = "--keyring";
      Args[i++] = pubringpath.c_str();

      Configuration::Item const *Opts;
      Opts = _config->Tree("Acquire::gpgv::Options");
      if (Opts != 0)
      {
         Opts = Opts->Child;
	 for (; Opts != 0; Opts = Opts->Next)
         {
            if (Opts->Value.empty() == true)
               continue;
            Args[i++] = Opts->Value.c_str();
	    if(i >= 395) { 
	       std::cerr << _("E: Argument list from Acquire::gpgv::Options too long. Exiting.") << std::endl;
	       exit(111);
	    }
         }
      }
      Args[i++] = file;
      Args[i++] = outfile;
      Args[i++] = NULL;

      if (_config->FindB("Debug::Acquire::gpgv", false))
      {
         std::cerr << "Preparing to exec: " << gpgvpath;
	 for(unsigned int j=0;Args[j] != NULL; j++)
	    std::cerr << " " << Args[j];
	 std::cerr << std::endl;
      }
      int nullfd = open("/dev/null", O_RDONLY);
      close(fd[0]);
      // Redirect output to /dev/null; we read from the status fd
      dup2(nullfd, STDOUT_FILENO); 
      dup2(nullfd, STDERR_FILENO); 
      // Redirect the pipe to the status fd (3)
      dup2(fd[1], 3);

      putenv("LANG=");
      putenv("LC_ALL=");
      putenv("LC_MESSAGES=");
      execvp(gpgvpath.c_str(), (char **)Args);
             
      exit(111);
   }
   close(fd[1]);

   pipein = fdopen(fd[0], "r"); 
   
   // Loop over the output of gpgv, and check the signatures.
   size_t buffersize = 64;
   char *buffer = (char *) malloc(buffersize);
   size_t bufferoff = 0;
   while (1)
   {
      int c;

      // Read a line.  Sigh.
      while ((c = getc(pipein)) != EOF && c != '\n')
      {
         if (bufferoff == buffersize)
            buffer = (char *) realloc(buffer, buffersize *= 2);
         *(buffer+bufferoff) = c;
         bufferoff++;
      }
      if (bufferoff == 0 && c == EOF)
         break;
      *(buffer+bufferoff) = '\0';
      bufferoff = 0;
      if (_config->FindB("Debug::Acquire::gpgv", false))
         std::cerr << "Read: " << buffer << std::endl;

      // Push the data into three separate vectors, which
      // we later concatenate.  They're kept separate so
      // if we improve the apt method communication stuff later
      // it will be better.
      if (strncmp(buffer, GNUPGBADSIG, sizeof(GNUPGBADSIG)-1) == 0)
      {
         if (_config->FindB("Debug::Acquire::gpgv", false))
            std::cerr << "Got BADSIG! " << std::endl;
         BadSigners.push_back(string(buffer+sizeof(GNUPGPREFIX)));
      }
      
      if (strncmp(buffer, GNUPGNOPUBKEY, sizeof(GNUPGNOPUBKEY)-1) == 0)
      {
         if (_config->FindB("Debug::Acquire::gpgv", false))
            std::cerr << "Got NO_PUBKEY " << std::endl;
         NoPubKeySigners.push_back(string(buffer+sizeof(GNUPGPREFIX)));
      }

      if (strncmp(buffer, GNUPGVALIDSIG, sizeof(GNUPGVALIDSIG)-1) == 0)
      {
         char *sig = buffer + sizeof(GNUPGPREFIX);
         char *p = sig + sizeof("VALIDSIG");
         while (*p && isxdigit(*p)) 
            p++;
         *p = 0;
         if (_config->FindB("Debug::Acquire::gpgv", false))
            std::cerr << "Got VALIDSIG, key ID:" << sig << std::endl;
         GoodSigners.push_back(string(sig));
      }
   }
   fclose(pipein);

   waitpid(pid, &status, 0);
   if (_config->FindB("Debug::Acquire::gpgv", false))
   {
      std::cerr << "gpgv exited\n";
   }
   
   if (WEXITSTATUS(status) == 0)
   {
      if (GoodSigners.empty())
         return _("Internal error: Good signature, but could not determine key fingerprint?!");
      return NULL;
   }
   else if (WEXITSTATUS(status) == 1)
   {
      return _("At least one invalid signature was encountered.");
   }
   else if (WEXITSTATUS(status) == 111)
   {
      // FIXME String concatenation considered harmful.
      return (string(_("Could not execute ")) + gpgvpath +
	      string(_(" to verify signature (is gnupg installed?)"))).c_str();
   }
   else
   {
      return _("Unknown error executing gpgv");
   }
}

bool GPGVMethod::Fetch(FetchItem *Itm)
{
   URI Get = Itm->Uri;
   string Path = Get.Host + Get.Path; // To account for relative paths
   string keyID;
   vector<string> GoodSigners;
   vector<string> BadSigners;
   vector<string> NoPubKeySigners;
   
   FetchResult Res;
   Res.Filename = Itm->DestFile;
   URIStart(Res);

   // Run gpgv on file, extract contents and get the key ID of the signer
   const char *msg = VerifyGetSigners(Path.c_str(), Itm->DestFile.c_str(),
				      GoodSigners, BadSigners, NoPubKeySigners);
   if (GoodSigners.empty() || !BadSigners.empty() || !NoPubKeySigners.empty())
   {
      string errmsg;
      // In this case, something bad probably happened, so we just go
      // with what the other method gave us for an error message.
      if (BadSigners.empty() && NoPubKeySigners.empty())
         errmsg = msg;
      else
      {
         if (!BadSigners.empty())
         {
            errmsg += _("The following signatures were invalid:\n");
            for (vector<string>::iterator I = BadSigners.begin();
		 I != BadSigners.end(); I++)
               errmsg += (*I + "\n");
         }
         if (!NoPubKeySigners.empty())
         {
             errmsg += _("The following signatures couldn't be verified because the public key is not available:\n");
            for (vector<string>::iterator I = NoPubKeySigners.begin();
		 I != NoPubKeySigners.end(); I++)
               errmsg += (*I + "\n");
         }
      }
      // this is only fatal if we have no good sigs or if we have at
      // least one bad signature. good signatures and NoPubKey signatures
      // happen easily when a file is signed with multiple signatures
      if(GoodSigners.empty() or !BadSigners.empty())
      	 return _error->Error(errmsg.c_str());
   }
      
   // Transfer the modification times
   struct stat Buf;
   if (stat(Path.c_str(),&Buf) != 0)
      return _error->Errno("stat",_("Failed to stat %s"), Path.c_str());

   struct utimbuf TimeBuf;
   TimeBuf.actime = Buf.st_atime;
   TimeBuf.modtime = Buf.st_mtime;
   if (utime(Itm->DestFile.c_str(),&TimeBuf) != 0)
      return _error->Errno("utime",_("Failed to set modification time"));

   if (stat(Itm->DestFile.c_str(),&Buf) != 0)
      return _error->Errno("stat",_("Failed to stat"));
   
   // Return a Done response
   Res.LastModified = Buf.st_mtime;
   Res.Size = Buf.st_size;
   // Just pass the raw output up, because passing it as a real data
   // structure is too difficult with the method stuff.  We keep it
   // as three separate vectors for future extensibility.
   Res.GPGVOutput = GoodSigners;
   Res.GPGVOutput.insert(Res.GPGVOutput.end(),BadSigners.begin(),BadSigners.end());
   Res.GPGVOutput.insert(Res.GPGVOutput.end(),NoPubKeySigners.begin(),NoPubKeySigners.end());
   URIDone(Res);

   if (_config->FindB("Debug::Acquire::gpgv", false))
   {
      std::cerr << "gpgv succeeded\n";
   }

   return true;
}


int main()
{
   setlocale(LC_ALL, "");
   
   GPGVMethod Mth;

   return Mth.Run();
}
Commit	Line	Data
b3d44315 MV	1	#include <apt-pkg/error.h>
	2	#include <apt-pkg/acquire-method.h>
	3	#include <apt-pkg/strutl.h>
339690e4	4	#include <apti18n.h>
b3d44315 MV	5
	6	#include <sys/stat.h>
	7	#include <unistd.h>
	8	#include <utime.h>
	9	#include <stdio.h>
	10	#include <fcntl.h>
	11	#include <errno.h>
	12	#include <sys/wait.h>
	13	#include <iostream>
	14
	15	#define GNUPGPREFIX "[GNUPG:]"
	16	#define GNUPGBADSIG "[GNUPG:] BADSIG"
	17	#define GNUPGNOPUBKEY "[GNUPG:] NO_PUBKEY"
	18	#define GNUPGVALIDSIG "[GNUPG:] VALIDSIG"
	19
	20	class GPGVMethod : public pkgAcqMethod
	21	{
	22	private:
	23	const char VerifyGetSigners(const char file, const char *outfile,
	24	vector<string> &GoodSigners, vector<string> &BadSigners,
	25	vector<string> &NoPubKeySigners);
	26
	27	protected:
	28	virtual bool Fetch(FetchItem *Itm);
	29
	30	public:
	31
	32	GPGVMethod() : pkgAcqMethod("1.0",SingleInstance \| SendConfig) {};
	33	};
	34
	35	const char GPGVMethod::VerifyGetSigners(const char file, const char *outfile,
	36	vector<string> &GoodSigners,
	37	vector<string> &BadSigners,
	38	vector<string> &NoPubKeySigners)
	39	{
	40	if (_config->FindB("Debug::Acquire::gpgv", false))
	41	{
	42	std::cerr << "inside VerifyGetSigners" << std::endl;
	43	}
	44	pid_t pid;
	45	int fd[2];
	46	FILE *pipein;
	47	int status;
	48	struct stat buff;
	49	string gpgvpath = _config->Find("Dir::Bin::gpg", "/usr/bin/gpgv");
8a3642bd	50	string pubringpath = _config->Find("APT::GPGV::TrustedKeyring", "/etc/apt/trusted.gpg");
b3d44315 MV	51	if (_config->FindB("Debug::Acquire::gpgv", false))
	52	{
	53	std::cerr << "gpgv path: " << gpgvpath << std::endl;
	54	std::cerr << "Keyring path: " << pubringpath << std::endl;
	55	}
	56
	57	if (stat(pubringpath.c_str(), &buff) != 0)
	58	return (string("Couldn't access keyring: ") + strerror(errno)).c_str();
	59
	60	if (pipe(fd) < 0)
	61	{
	62	return "Couldn't create pipe";
	63	}
	64
	65	pid = fork();
	66	if (pid < 0)
	67	{
	68	return (string("Couldn't spawn new process") + strerror(errno)).c_str();
	69	}
	70	else if (pid == 0)
	71	{
ad6a45d8 MV	72	const char *Args[400];
	73	unsigned int i = 0;
	74
	75	Args[i++] = gpgvpath.c_str();
	76	Args[i++] = "--status-fd";
	77	Args[i++] = "3";
	78	Args[i++] = "--keyring";
	79	Args[i++] = pubringpath.c_str();
	80
	81	Configuration::Item const *Opts;
	82	Opts = _config->Tree("Acquire::gpgv::Options");
	83	if (Opts != 0)
	84	{
	85	Opts = Opts->Child;
	86	for (; Opts != 0; Opts = Opts->Next)
	87	{
	88	if (Opts->Value.empty() == true)
	89	continue;
	90	Args[i++] = Opts->Value.c_str();
	91	if(i >= 395) {
339690e4	92	std::cerr << _("E: Argument list from Acquire::gpgv::Options too long. Exiting.") << std::endl;
ad6a45d8 MV	93	exit(111);
	94	}
	95	}
	96	}
	97	Args[i++] = file;
	98	Args[i++] = outfile;
	99	Args[i++] = NULL;
	100
b3d44315 MV	101	if (_config->FindB("Debug::Acquire::gpgv", false))
b3d44315 MV	102	{
ad6a45d8	103	std::cerr << "Preparing to exec: " << gpgvpath;
ec048f63	104	for(unsigned int j=0;Args[j] != NULL; j++)
af45f087	105	std::cerr << " " << Args[j];
ad6a45d8	106	std::cerr << std::endl;
b3d44315 MV	107	}
	108	int nullfd = open("/dev/null", O_RDONLY);
	109	close(fd[0]);
	110	// Redirect output to /dev/null; we read from the status fd
	111	dup2(nullfd, STDOUT_FILENO);
	112	dup2(nullfd, STDERR_FILENO);
	113	// Redirect the pipe to the status fd (3)
	114	dup2(fd[1], 3);
	115
	116	putenv("LANG=");
	117	putenv("LC_ALL=");
	118	putenv("LC_MESSAGES=");
ad6a45d8	119	execvp(gpgvpath.c_str(), (char **)Args);
b3d44315 MV	120
	121	exit(111);
	122	}
	123	close(fd[1]);
	124
	125	pipein = fdopen(fd[0], "r");
	126
	127	// Loop over the output of gpgv, and check the signatures.
	128	size_t buffersize = 64;
	129	char buffer = (char ) malloc(buffersize);
	130	size_t bufferoff = 0;
	131	while (1)
	132	{
	133	int c;
	134
	135	// Read a line. Sigh.
	136	while ((c = getc(pipein)) != EOF && c != '\n')
	137	{
	138	if (bufferoff == buffersize)
	139	buffer = (char ) realloc(buffer, buffersize = 2);
	140	*(buffer+bufferoff) = c;
	141	bufferoff++;
	142	}
	143	if (bufferoff == 0 && c == EOF)
	144	break;
	145	*(buffer+bufferoff) = '\0';
	146	bufferoff = 0;
	147	if (_config->FindB("Debug::Acquire::gpgv", false))
	148	std::cerr << "Read: " << buffer << std::endl;
	149
	150	// Push the data into three separate vectors, which
	151	// we later concatenate. They're kept separate so
	152	// if we improve the apt method communication stuff later
	153	// it will be better.
	154	if (strncmp(buffer, GNUPGBADSIG, sizeof(GNUPGBADSIG)-1) == 0)
	155	{
	156	if (_config->FindB("Debug::Acquire::gpgv", false))
	157	std::cerr << "Got BADSIG! " << std::endl;
	158	BadSigners.push_back(string(buffer+sizeof(GNUPGPREFIX)));
	159	}
	160
	161	if (strncmp(buffer, GNUPGNOPUBKEY, sizeof(GNUPGNOPUBKEY)-1) == 0)
	162	{
	163	if (_config->FindB("Debug::Acquire::gpgv", false))
	164	std::cerr << "Got NO_PUBKEY " << std::endl;
	165	NoPubKeySigners.push_back(string(buffer+sizeof(GNUPGPREFIX)));
	166	}
	167
	168	if (strncmp(buffer, GNUPGVALIDSIG, sizeof(GNUPGVALIDSIG)-1) == 0)
	169	{
	170	char *sig = buffer + sizeof(GNUPGPREFIX);
	171	char *p = sig + sizeof("VALIDSIG");
	172	while (p && isxdigit(p))
	173	p++;
	174	*p = 0;
	175	if (_config->FindB("Debug::Acquire::gpgv", false))
	176	std::cerr << "Got VALIDSIG, key ID:" << sig << std::endl;
	177	GoodSigners.push_back(string(sig));
	178	}
	179	}
	180	fclose(pipein);
	181
	182	waitpid(pid, &status, 0);
	183	if (_config->FindB("Debug::Acquire::gpgv", false))
184	{
339690e4	185	std::cerr << "gpgv exited\n";
b3d44315 MV	186	}
	187
	188	if (WEXITSTATUS(status) == 0)
	189	{
	190	if (GoodSigners.empty())
339690e4	191	return _("Internal error: Good signature, but could not determine key fingerprint?!");
b3d44315 MV	192	return NULL;
	193	}
	194	else if (WEXITSTATUS(status) == 1)
	195	{
339690e4	196	return _("At least one invalid signature was encountered.");
b3d44315 MV	197	}
	198	else if (WEXITSTATUS(status) == 111)
	199	{
339690e4 MV	200	// FIXME String concatenation considered harmful.
	201	return (string(_("Could not execute ")) + gpgvpath +
	202	string(_(" to verify signature (is gnupg installed?)"))).c_str();
b3d44315 MV	203	}
	204	else
	205	{
339690e4	206	return _("Unknown error executing gpgv");
b3d44315 MV	207	}
	208	}
	209
	210	bool GPGVMethod::Fetch(FetchItem *Itm)
	211	{
	212	URI Get = Itm->Uri;
	213	string Path = Get.Host + Get.Path; // To account for relative paths
	214	string keyID;
	215	vector<string> GoodSigners;
	216	vector<string> BadSigners;
	217	vector<string> NoPubKeySigners;
	218
	219	FetchResult Res;
	220	Res.Filename = Itm->DestFile;
	221	URIStart(Res);
	222
	223	// Run gpgv on file, extract contents and get the key ID of the signer
	224	const char *msg = VerifyGetSigners(Path.c_str(), Itm->DestFile.c_str(),
	225	GoodSigners, BadSigners, NoPubKeySigners);
	226	if (GoodSigners.empty() \|\| !BadSigners.empty() \|\| !NoPubKeySigners.empty())
	227	{
	228	string errmsg;
	229	// In this case, something bad probably happened, so we just go
	230	// with what the other method gave us for an error message.
	231	if (BadSigners.empty() && NoPubKeySigners.empty())
	232	errmsg = msg;
	233	else
	234	{
	235	if (!BadSigners.empty())
	236	{
339690e4	237	errmsg += _("The following signatures were invalid:\n");
b3d44315 MV	238	for (vector<string>::iterator I = BadSigners.begin();
	239	I != BadSigners.end(); I++)
	240	errmsg += (*I + "\n");
	241	}
	242	if (!NoPubKeySigners.empty())
	243	{
339690e4	244	errmsg += _("The following signatures couldn't be verified because the public key is not available:\n");
b3d44315 MV	245	for (vector<string>::iterator I = NoPubKeySigners.begin();
	246	I != NoPubKeySigners.end(); I++)
	247	errmsg += (*I + "\n");
	248	}
	249	}
ce424cd4 MV	250	// this is only fatal if we have no good sigs or if we have at
	251	// least one bad signature. good signatures and NoPubKey signatures
	252	// happen easily when a file is signed with multiple signatures
	253	if(GoodSigners.empty() or !BadSigners.empty())
	254	return _error->Error(errmsg.c_str());
b3d44315 MV	255	}
	256
	257	// Transfer the modification times
	258	struct stat Buf;
	259	if (stat(Path.c_str(),&Buf) != 0)
339690e4	260	return _error->Errno("stat",_("Failed to stat %s"), Path.c_str());
b3d44315 MV	261
	262	struct utimbuf TimeBuf;
	263	TimeBuf.actime = Buf.st_atime;
	264	TimeBuf.modtime = Buf.st_mtime;
	265	if (utime(Itm->DestFile.c_str(),&TimeBuf) != 0)
339690e4	266	return _error->Errno("utime",_("Failed to set modification time"));
b3d44315 MV	267
b3d44315 MV	268	if (stat(Itm->DestFile.c_str(),&Buf) != 0)
339690e4	269	return _error->Errno("stat",_("Failed to stat"));
b3d44315 MV	270
	271	// Return a Done response
	272	Res.LastModified = Buf.st_mtime;
	273	Res.Size = Buf.st_size;
	274	// Just pass the raw output up, because passing it as a real data
	275	// structure is too difficult with the method stuff. We keep it
	276	// as three separate vectors for future extensibility.
	277	Res.GPGVOutput = GoodSigners;
	278	Res.GPGVOutput.insert(Res.GPGVOutput.end(),BadSigners.begin(),BadSigners.end());
	279	Res.GPGVOutput.insert(Res.GPGVOutput.end(),NoPubKeySigners.begin(),NoPubKeySigners.end());
	280	URIDone(Res);
	281
	282	if (_config->FindB("Debug::Acquire::gpgv", false))
	283	{
339690e4	284	std::cerr << "gpgv succeeded\n";
b3d44315 MV	285	}
	286
	287	return true;
	288	}
	289
	290
	291	int main()
	292	{
339690e4 MV	293	setlocale(LC_ALL, "");
339690e4 MV	294
b3d44315 MV	295	GPGVMethod Mth;
	296
	297	return Mth.Run();
	298	}