[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>
#include <sstream>

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

class GPGVMethod : public pkgAcqMethod
{
   private:
   string 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) {};
};

string GPGVMethod::VerifyGetSigners(const char *file, const char *outfile,
					 vector<string> &GoodSigners,
					 vector<string> &BadSigners,
					 vector<string> &NoPubKeySigners)
{
   // setup a (empty) stringstream for formating the return value
   std::stringstream ret;
   ret.str("");

   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) 
   {
      ioprintf(ret, _("Couldn't access keyring: '%s'"), strerror(errno)); 
      return ret.str();
   }
   if (pipe(fd) < 0)
   {
      return "Couldn't create pipe";
   }

   pid = fork();
   if (pid < 0)
   {
      return string("Couldn't spawn new process") + strerror(errno);
   }
   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 "";
   }
   else if (WEXITSTATUS(status) == 1)
   {
      return _("At least one invalid signature was encountered.");
   }
   else if (WEXITSTATUS(status) == 111)
   {
      ioprintf(ret, _("Could not execute '%s' to verify signature (is gnupg installed?)"), gpgvpath.c_str());
      return ret.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
   string 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>
da9ed163	14	#include <sstream>
b3d44315 MV	15
	16	#define GNUPGPREFIX "[GNUPG:]"
	17	#define GNUPGBADSIG "[GNUPG:] BADSIG"
	18	#define GNUPGNOPUBKEY "[GNUPG:] NO_PUBKEY"
	19	#define GNUPGVALIDSIG "[GNUPG:] VALIDSIG"
	20
	21	class GPGVMethod : public pkgAcqMethod
	22	{
	23	private:
da9ed163	24	string VerifyGetSigners(const char file, const char outfile,
b3d44315 MV	25	vector<string> &GoodSigners, vector<string> &BadSigners,
	26	vector<string> &NoPubKeySigners);
	27
	28	protected:
	29	virtual bool Fetch(FetchItem *Itm);
	30
	31	public:
	32
	33	GPGVMethod() : pkgAcqMethod("1.0",SingleInstance \| SendConfig) {};
	34	};
	35
da9ed163	36	string GPGVMethod::VerifyGetSigners(const char file, const char outfile,
b3d44315 MV	37	vector<string> &GoodSigners,
	38	vector<string> &BadSigners,
	39	vector<string> &NoPubKeySigners)
	40	{
da9ed163 MV	41	// setup a (empty) stringstream for formating the return value
da9ed163 MV	42	std::stringstream ret;
b2c22075	43	ret.str("");
da9ed163	44
b3d44315 MV	45	if (_config->FindB("Debug::Acquire::gpgv", false))
	46	{
	47	std::cerr << "inside VerifyGetSigners" << std::endl;
	48	}
	49	pid_t pid;
	50	int fd[2];
	51	FILE *pipein;
	52	int status;
	53	struct stat buff;
	54	string gpgvpath = _config->Find("Dir::Bin::gpg", "/usr/bin/gpgv");
8a3642bd	55	string pubringpath = _config->Find("APT::GPGV::TrustedKeyring", "/etc/apt/trusted.gpg");
b3d44315 MV	56	if (_config->FindB("Debug::Acquire::gpgv", false))
	57	{
	58	std::cerr << "gpgv path: " << gpgvpath << std::endl;
	59	std::cerr << "Keyring path: " << pubringpath << std::endl;
	60	}
	61
da9ed163 MV	62	if (stat(pubringpath.c_str(), &buff) != 0)
	63	{
	64	ioprintf(ret, _("Couldn't access keyring: '%s'"), strerror(errno));
	65	return ret.str();
	66	}
b3d44315 MV	67	if (pipe(fd) < 0)
	68	{
	69	return "Couldn't create pipe";
	70	}
	71
	72	pid = fork();
	73	if (pid < 0)
	74	{
da9ed163	75	return string("Couldn't spawn new process") + strerror(errno);
b3d44315 MV	76	}
	77	else if (pid == 0)
	78	{
ad6a45d8 MV	79	const char *Args[400];
	80	unsigned int i = 0;
	81
	82	Args[i++] = gpgvpath.c_str();
	83	Args[i++] = "--status-fd";
	84	Args[i++] = "3";
	85	Args[i++] = "--keyring";
	86	Args[i++] = pubringpath.c_str();
	87
	88	Configuration::Item const *Opts;
	89	Opts = _config->Tree("Acquire::gpgv::Options");
	90	if (Opts != 0)
	91	{
	92	Opts = Opts->Child;
	93	for (; Opts != 0; Opts = Opts->Next)
	94	{
	95	if (Opts->Value.empty() == true)
	96	continue;
	97	Args[i++] = Opts->Value.c_str();
	98	if(i >= 395) {
339690e4	99	std::cerr << _("E: Argument list from Acquire::gpgv::Options too long. Exiting.") << std::endl;
ad6a45d8 MV	100	exit(111);
	101	}
	102	}
	103	}
	104	Args[i++] = file;
	105	Args[i++] = outfile;
	106	Args[i++] = NULL;
	107
b3d44315 MV	108	if (_config->FindB("Debug::Acquire::gpgv", false))
b3d44315 MV	109	{
ad6a45d8	110	std::cerr << "Preparing to exec: " << gpgvpath;
ec048f63	111	for(unsigned int j=0;Args[j] != NULL; j++)
af45f087	112	std::cerr << " " << Args[j];
ad6a45d8	113	std::cerr << std::endl;
b3d44315 MV	114	}
	115	int nullfd = open("/dev/null", O_RDONLY);
	116	close(fd[0]);
	117	// Redirect output to /dev/null; we read from the status fd
	118	dup2(nullfd, STDOUT_FILENO);
	119	dup2(nullfd, STDERR_FILENO);
	120	// Redirect the pipe to the status fd (3)
	121	dup2(fd[1], 3);
	122
	123	putenv("LANG=");
	124	putenv("LC_ALL=");
	125	putenv("LC_MESSAGES=");
ad6a45d8	126	execvp(gpgvpath.c_str(), (char **)Args);
b3d44315 MV	127
	128	exit(111);
	129	}
	130	close(fd[1]);
	131
	132	pipein = fdopen(fd[0], "r");
	133
	134	// Loop over the output of gpgv, and check the signatures.
	135	size_t buffersize = 64;
	136	char buffer = (char ) malloc(buffersize);
	137	size_t bufferoff = 0;
	138	while (1)
	139	{
	140	int c;
	141
	142	// Read a line. Sigh.
	143	while ((c = getc(pipein)) != EOF && c != '\n')
	144	{
	145	if (bufferoff == buffersize)
	146	buffer = (char ) realloc(buffer, buffersize = 2);
	147	*(buffer+bufferoff) = c;
	148	bufferoff++;
	149	}
	150	if (bufferoff == 0 && c == EOF)
	151	break;
	152	*(buffer+bufferoff) = '\0';
	153	bufferoff = 0;
	154	if (_config->FindB("Debug::Acquire::gpgv", false))
	155	std::cerr << "Read: " << buffer << std::endl;
	156
	157	// Push the data into three separate vectors, which
	158	// we later concatenate. They're kept separate so
	159	// if we improve the apt method communication stuff later
	160	// it will be better.
	161	if (strncmp(buffer, GNUPGBADSIG, sizeof(GNUPGBADSIG)-1) == 0)
	162	{
	163	if (_config->FindB("Debug::Acquire::gpgv", false))
	164	std::cerr << "Got BADSIG! " << std::endl;
	165	BadSigners.push_back(string(buffer+sizeof(GNUPGPREFIX)));
	166	}
	167
	168	if (strncmp(buffer, GNUPGNOPUBKEY, sizeof(GNUPGNOPUBKEY)-1) == 0)
	169	{
	170	if (_config->FindB("Debug::Acquire::gpgv", false))
	171	std::cerr << "Got NO_PUBKEY " << std::endl;
	172	NoPubKeySigners.push_back(string(buffer+sizeof(GNUPGPREFIX)));
	173	}
	174
	175	if (strncmp(buffer, GNUPGVALIDSIG, sizeof(GNUPGVALIDSIG)-1) == 0)
	176	{
	177	char *sig = buffer + sizeof(GNUPGPREFIX);
	178	char *p = sig + sizeof("VALIDSIG");
	179	while (p && isxdigit(p))
	180	p++;
	181	*p = 0;
	182	if (_config->FindB("Debug::Acquire::gpgv", false))
	183	std::cerr << "Got VALIDSIG, key ID:" << sig << std::endl;
	184	GoodSigners.push_back(string(sig));
	185	}
	186	}
	187	fclose(pipein);
	188
	189	waitpid(pid, &status, 0);
	190	if (_config->FindB("Debug::Acquire::gpgv", false))
191	{
339690e4	192	std::cerr << "gpgv exited\n";
b3d44315 MV	193	}
	194
	195	if (WEXITSTATUS(status) == 0)
	196	{
	197	if (GoodSigners.empty())
339690e4	198	return _("Internal error: Good signature, but could not determine key fingerprint?!");
da9ed163	199	return "";
b3d44315 MV	200	}
	201	else if (WEXITSTATUS(status) == 1)
	202	{
339690e4	203	return _("At least one invalid signature was encountered.");
b3d44315 MV	204	}
	205	else if (WEXITSTATUS(status) == 111)
	206	{
da9ed163 MV	207	ioprintf(ret, _("Could not execute '%s' to verify signature (is gnupg installed?)"), gpgvpath.c_str());
da9ed163 MV	208	return ret.str();
b3d44315 MV	209	}
	210	else
	211	{
339690e4	212	return _("Unknown error executing gpgv");
b3d44315 MV	213	}
	214	}
	215
	216	bool GPGVMethod::Fetch(FetchItem *Itm)
	217	{
	218	URI Get = Itm->Uri;
	219	string Path = Get.Host + Get.Path; // To account for relative paths
	220	string keyID;
	221	vector<string> GoodSigners;
	222	vector<string> BadSigners;
	223	vector<string> NoPubKeySigners;
	224
	225	FetchResult Res;
	226	Res.Filename = Itm->DestFile;
	227	URIStart(Res);
	228
	229	// Run gpgv on file, extract contents and get the key ID of the signer
da9ed163 MV	230	string msg = VerifyGetSigners(Path.c_str(), Itm->DestFile.c_str(),
da9ed163 MV	231	GoodSigners, BadSigners, NoPubKeySigners);
b3d44315 MV	232	if (GoodSigners.empty() \|\| !BadSigners.empty() \|\| !NoPubKeySigners.empty())
	233	{
	234	string errmsg;
	235	// In this case, something bad probably happened, so we just go
	236	// with what the other method gave us for an error message.
	237	if (BadSigners.empty() && NoPubKeySigners.empty())
	238	errmsg = msg;
	239	else
	240	{
	241	if (!BadSigners.empty())
	242	{
339690e4	243	errmsg += _("The following signatures were invalid:\n");
b3d44315 MV	244	for (vector<string>::iterator I = BadSigners.begin();
	245	I != BadSigners.end(); I++)
	246	errmsg += (*I + "\n");
	247	}
	248	if (!NoPubKeySigners.empty())
	249	{
339690e4	250	errmsg += _("The following signatures couldn't be verified because the public key is not available:\n");
b3d44315 MV	251	for (vector<string>::iterator I = NoPubKeySigners.begin();
	252	I != NoPubKeySigners.end(); I++)
	253	errmsg += (*I + "\n");
	254	}
	255	}
ce424cd4 MV	256	// this is only fatal if we have no good sigs or if we have at
	257	// least one bad signature. good signatures and NoPubKey signatures
	258	// happen easily when a file is signed with multiple signatures
	259	if(GoodSigners.empty() or !BadSigners.empty())
	260	return _error->Error(errmsg.c_str());
b3d44315 MV	261	}
	262
	263	// Transfer the modification times
	264	struct stat Buf;
	265	if (stat(Path.c_str(),&Buf) != 0)
339690e4	266	return _error->Errno("stat",_("Failed to stat %s"), Path.c_str());
b3d44315 MV	267
	268	struct utimbuf TimeBuf;
	269	TimeBuf.actime = Buf.st_atime;
	270	TimeBuf.modtime = Buf.st_mtime;
	271	if (utime(Itm->DestFile.c_str(),&TimeBuf) != 0)
339690e4	272	return _error->Errno("utime",_("Failed to set modification time"));
b3d44315 MV	273
b3d44315 MV	274	if (stat(Itm->DestFile.c_str(),&Buf) != 0)
339690e4	275	return _error->Errno("stat",_("Failed to stat"));
b3d44315 MV	276
	277	// Return a Done response
	278	Res.LastModified = Buf.st_mtime;
	279	Res.Size = Buf.st_size;
	280	// Just pass the raw output up, because passing it as a real data
	281	// structure is too difficult with the method stuff. We keep it
	282	// as three separate vectors for future extensibility.
	283	Res.GPGVOutput = GoodSigners;
	284	Res.GPGVOutput.insert(Res.GPGVOutput.end(),BadSigners.begin(),BadSigners.end());
	285	Res.GPGVOutput.insert(Res.GPGVOutput.end(),NoPubKeySigners.begin(),NoPubKeySigners.end());
	286	URIDone(Res);
	287
	288	if (_config->FindB("Debug::Acquire::gpgv", false))
	289	{
339690e4	290	std::cerr << "gpgv succeeded\n";
b3d44315 MV	291	}
	292
	293	return true;
	294	}
	295
	296
	297	int main()
	298	{
339690e4 MV	299	setlocale(LC_ALL, "");
339690e4 MV	300
b3d44315 MV	301	GPGVMethod Mth;
	302
	303	return Mth.Run();
	304	}