[apt.git] / methods / gpgv.cc

#include <apt-pkg/error.h>
#include <apt-pkg/acquire-method.h>
#include <apt-pkg/strutl.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)
   {
      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");
         }
      }
      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 suceeded\n";
   }

   return true;
}


int main()
{
   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>
	4
	5	#include <sys/stat.h>
	6	#include <unistd.h>
	7	#include <utime.h>
	8	#include <stdio.h>
	9	#include <fcntl.h>
	10	#include <errno.h>
	11	#include <sys/wait.h>
	12	#include <iostream>
	13
	14	#define GNUPGPREFIX "[GNUPG:]"
	15	#define GNUPGBADSIG "[GNUPG:] BADSIG"
	16	#define GNUPGNOPUBKEY "[GNUPG:] NO_PUBKEY"
	17	#define GNUPGVALIDSIG "[GNUPG:] VALIDSIG"
	18
	19	class GPGVMethod : public pkgAcqMethod
	20	{
	21	private:
	22	const char VerifyGetSigners(const char file, const char *outfile,
	23	vector<string> &GoodSigners, vector<string> &BadSigners,
	24	vector<string> &NoPubKeySigners);
	25
	26	protected:
	27	virtual bool Fetch(FetchItem *Itm);
	28
	29	public:
	30
	31	GPGVMethod() : pkgAcqMethod("1.0",SingleInstance \| SendConfig) {};
	32	};
	33
	34	const char GPGVMethod::VerifyGetSigners(const char file, const char *outfile,
	35	vector<string> &GoodSigners,
	36	vector<string> &BadSigners,
	37	vector<string> &NoPubKeySigners)
	38	{
	39	if (_config->FindB("Debug::Acquire::gpgv", false))
	40	{
	41	std::cerr << "inside VerifyGetSigners" << std::endl;
	42	}
	43	pid_t pid;
	44	int fd[2];
	45	FILE *pipein;
	46	int status;
	47	struct stat buff;
	48	string gpgvpath = _config->Find("Dir::Bin::gpg", "/usr/bin/gpgv");
	49	string pubringpath = _config->Find("Apt::GPGV::TrustedKeyring", "/etc/apt/trusted.gpg");
	50	if (_config->FindB("Debug::Acquire::gpgv", false))
	51	{
	52	std::cerr << "gpgv path: " << gpgvpath << std::endl;
	53	std::cerr << "Keyring path: " << pubringpath << std::endl;
	54	}
	55
	56	if (stat(pubringpath.c_str(), &buff) != 0)
	57	return (string("Couldn't access keyring: ") + strerror(errno)).c_str();
	58
	59	if (pipe(fd) < 0)
	60	{
	61	return "Couldn't create pipe";
	62	}
	63
	64	pid = fork();
65	if (pid < 0)
66	{
67	return (string("Couldn't spawn new process") + strerror(errno)).c_str();
68	}
69	else if (pid == 0)
70	{
ad6a45d8 MV	71	const char *Args[400];
	72	unsigned int i = 0;
	73
	74	Args[i++] = gpgvpath.c_str();
	75	Args[i++] = "--status-fd";
	76	Args[i++] = "3";
	77	Args[i++] = "--keyring";
	78	Args[i++] = pubringpath.c_str();
	79
	80	Configuration::Item const *Opts;
	81	Opts = _config->Tree("Acquire::gpgv::Options");
	82	if (Opts != 0)
	83	{
	84	Opts = Opts->Child;
	85	for (; Opts != 0; Opts = Opts->Next)
	86	{
	87	if (Opts->Value.empty() == true)
	88	continue;
	89	Args[i++] = Opts->Value.c_str();
	90	if(i >= 395) {
	91	std::cerr << "E: Argument list from Acquire::gpgv::Options too long. Exiting." << std::endl;
	92	exit(111);
	93	}
	94	}
	95	}
	96	Args[i++] = file;
	97	Args[i++] = outfile;
	98	Args[i++] = NULL;
	99
b3d44315 MV	100	if (_config->FindB("Debug::Acquire::gpgv", false))
b3d44315 MV	101	{
ad6a45d8	102	std::cerr << "Preparing to exec: " << gpgvpath;
ec048f63	103	for(unsigned int j=0;Args[j] != NULL; j++)
ad6a45d8 MV	104	std::cerr << Args[j] << " ";
ad6a45d8 MV	105	std::cerr << std::endl;
b3d44315 MV	106	}
	107	int nullfd = open("/dev/null", O_RDONLY);
	108	close(fd[0]);
	109	// Redirect output to /dev/null; we read from the status fd
	110	dup2(nullfd, STDOUT_FILENO);
	111	dup2(nullfd, STDERR_FILENO);
	112	// Redirect the pipe to the status fd (3)
	113	dup2(fd[1], 3);
	114
	115	putenv("LANG=");
	116	putenv("LC_ALL=");
	117	putenv("LC_MESSAGES=");
ad6a45d8	118	execvp(gpgvpath.c_str(), (char **)Args);
b3d44315 MV	119
	120	exit(111);
	121	}
	122	close(fd[1]);
	123
	124	pipein = fdopen(fd[0], "r");
	125
	126	// Loop over the output of gpgv, and check the signatures.
	127	size_t buffersize = 64;
	128	char buffer = (char ) malloc(buffersize);
	129	size_t bufferoff = 0;
	130	while (1)
	131	{
	132	int c;
	133
	134	// Read a line. Sigh.
	135	while ((c = getc(pipein)) != EOF && c != '\n')
	136	{
	137	if (bufferoff == buffersize)
	138	buffer = (char ) realloc(buffer, buffersize = 2);
	139	*(buffer+bufferoff) = c;
	140	bufferoff++;
	141	}
	142	if (bufferoff == 0 && c == EOF)
	143	break;
	144	*(buffer+bufferoff) = '\0';
	145	bufferoff = 0;
	146	if (_config->FindB("Debug::Acquire::gpgv", false))
	147	std::cerr << "Read: " << buffer << std::endl;
	148
	149	// Push the data into three separate vectors, which
	150	// we later concatenate. They're kept separate so
	151	// if we improve the apt method communication stuff later
	152	// it will be better.
	153	if (strncmp(buffer, GNUPGBADSIG, sizeof(GNUPGBADSIG)-1) == 0)
	154	{
	155	if (_config->FindB("Debug::Acquire::gpgv", false))
	156	std::cerr << "Got BADSIG! " << std::endl;
	157	BadSigners.push_back(string(buffer+sizeof(GNUPGPREFIX)));
	158	}
	159
	160	if (strncmp(buffer, GNUPGNOPUBKEY, sizeof(GNUPGNOPUBKEY)-1) == 0)
	161	{
	162	if (_config->FindB("Debug::Acquire::gpgv", false))
	163	std::cerr << "Got NO_PUBKEY " << std::endl;
	164	NoPubKeySigners.push_back(string(buffer+sizeof(GNUPGPREFIX)));
	165	}
	166
	167	if (strncmp(buffer, GNUPGVALIDSIG, sizeof(GNUPGVALIDSIG)-1) == 0)
	168	{
	169	char *sig = buffer + sizeof(GNUPGPREFIX);
	170	char *p = sig + sizeof("VALIDSIG");
	171	while (p && isxdigit(p))
	172	p++;
	173	*p = 0;
	174	if (_config->FindB("Debug::Acquire::gpgv", false))
	175	std::cerr << "Got VALIDSIG, key ID:" << sig << std::endl;
	176	GoodSigners.push_back(string(sig));
	177	}
	178	}
	179	fclose(pipein);
	180
	181	waitpid(pid, &status, 0);
	182	if (_config->FindB("Debug::Acquire::gpgv", false))
183	{
184	std::cerr <<"gpgv exited\n";
185	}
186
187	if (WEXITSTATUS(status) == 0)
188	{
189	if (GoodSigners.empty())
190	return "Internal error: Good signature, but could not determine key fingerprint?!";
191	return NULL;
192	}
193	else if (WEXITSTATUS(status) == 1)
194	{
195	return "At least one invalid signature was encountered.";
196	}
197	else if (WEXITSTATUS(status) == 111)
198	{
199	return (string("Could not execute ") + gpgvpath +
200	string(" to verify signature (is gnupg installed?)")).c_str();
201	}
202	else
203	{
204	return "Unknown error executing gpgv";
205	}
206	}
207
208	bool GPGVMethod::Fetch(FetchItem *Itm)
209	{
210	URI Get = Itm->Uri;
211	string Path = Get.Host + Get.Path; // To account for relative paths
212	string keyID;
213	vector<string> GoodSigners;
214	vector<string> BadSigners;
215	vector<string> NoPubKeySigners;
216
217	FetchResult Res;
218	Res.Filename = Itm->DestFile;
219	URIStart(Res);
220
221	// Run gpgv on file, extract contents and get the key ID of the signer
222	const char *msg = VerifyGetSigners(Path.c_str(), Itm->DestFile.c_str(),
223	GoodSigners, BadSigners, NoPubKeySigners);
224	if (GoodSigners.empty() \|\| !BadSigners.empty() \|\| !NoPubKeySigners.empty())
225	{
226	string errmsg;
227	// In this case, something bad probably happened, so we just go
228	// with what the other method gave us for an error message.
229	if (BadSigners.empty() && NoPubKeySigners.empty())
230	errmsg = msg;
231	else
232	{
233	if (!BadSigners.empty())
234	{
235	errmsg += "The following signatures were invalid:\n";
236	for (vector<string>::iterator I = BadSigners.begin();
237	I != BadSigners.end(); I++)
238	errmsg += (*I + "\n");
239	}
240	if (!NoPubKeySigners.empty())
241	{
242	errmsg += "The following signatures couldn't be verified because the public key is not available:\n";
243	for (vector<string>::iterator I = NoPubKeySigners.begin();
244	I != NoPubKeySigners.end(); I++)
245	errmsg += (*I + "\n");
246	}
247	}
248	return _error->Error(errmsg.c_str());
249	}
250
251	// Transfer the modification times
252	struct stat Buf;
253	if (stat(Path.c_str(),&Buf) != 0)
254	return _error->Errno("stat","Failed to stat %s", Path.c_str());
255
256	struct utimbuf TimeBuf;
257	TimeBuf.actime = Buf.st_atime;
258	TimeBuf.modtime = Buf.st_mtime;
259	if (utime(Itm->DestFile.c_str(),&TimeBuf) != 0)
260	return _error->Errno("utime","Failed to set modification time");
261
262	if (stat(Itm->DestFile.c_str(),&Buf) != 0)
263	return _error->Errno("stat","Failed to stat");
264
265	// Return a Done response
266	Res.LastModified = Buf.st_mtime;
267	Res.Size = Buf.st_size;
268	// Just pass the raw output up, because passing it as a real data
269	// structure is too difficult with the method stuff. We keep it
270	// as three separate vectors for future extensibility.
271	Res.GPGVOutput = GoodSigners;
272	Res.GPGVOutput.insert(Res.GPGVOutput.end(),BadSigners.begin(),BadSigners.end());
273	Res.GPGVOutput.insert(Res.GPGVOutput.end(),NoPubKeySigners.begin(),NoPubKeySigners.end());
274	URIDone(Res);
275
276	if (_config->FindB("Debug::Acquire::gpgv", false))
277	{
278	std::cerr <<"gpgv suceeded\n";
279	}
280
281	return true;
282	}
283
284
285	int main()
286	{
287	GPGVMethod Mth;
288
289	return Mth.Run();
290	}