Add basic (non weight adjusted) shuffling for SrvRecords selection

[apt.git] / methods / rred.cc

diff --git a/methods/rred.cc b/methods/rred.cc
index 3da33c1267ba6414cc0e1dfafdfb8018c7d7f932..91b6dda222bcaa6bcad72ba5880c76e3e6de8344 100644 (file)
--- a/methods/rred.cc
+++ b/methods/rred.cc
@@ -21,6 +21,7 @@
 #include <vector>
 
 #include <assert.h>
+#include <errno.h>
 #include <stdio.h>
 #include <stdlib.h>
 #include <string.h>
@@ -35,7 +36,7 @@ class MemBlock {
    char *start;
    size_t size;
    char *free;
-   struct MemBlock *next;
+   MemBlock *next;
 
    MemBlock(size_t size) : size(size), next(NULL)
    {
@@ -116,7 +117,7 @@ struct Change {
    size_t add_len; /* bytes */
    char *add;
 
-   Change(int off)
+   Change(size_t off)
    {
       offset = off;
       del_cnt = add_cnt = add_len = 0;
@@ -388,30 +389,37 @@ class Patch {
 
    public:
 
-   void read_diff(FileFd &f, Hashes * const h)
+   bool read_diff(FileFd &f, Hashes * const h)
    {
       char buffer[BLOCK_SIZE];
       bool cmdwanted = true;
 
-      Change ch(0);
-      while(f.ReadLine(buffer, sizeof(buffer)))
-      {
+      Change ch(std::numeric_limits<size_t>::max());
+      if (f.ReadLine(buffer, sizeof(buffer)) == NULL)
+        return _error->Error("Reading first line of patchfile %s failed", f.Name().c_str());
+      do {
         if (h != NULL)
            h->Add(buffer);
         if (cmdwanted) {
            char *m, *c;
            size_t s, e;
-           s = strtol(buffer, &m, 10);
-           if (m == buffer) {
-              s = e = ch.offset + ch.add_cnt;
-              c = buffer;
-           } else if (*m == ',') {
-              m++;
+           errno = 0;
+           s = strtoul(buffer, &m, 10);
+           if (unlikely(m == buffer || s == std::numeric_limits<unsigned long>::max() || errno != 0))
+              return _error->Error("Parsing patchfile %s failed: Expected an effected line start", f.Name().c_str());
+           else if (*m == ',') {
+              ++m;
               e = strtol(m, &c, 10);
+              if (unlikely(m == c || e == std::numeric_limits<unsigned long>::max() || errno != 0))
+                 return _error->Error("Parsing patchfile %s failed: Expected an effected line end", f.Name().c_str());
+              if (unlikely(e < s))
+                 return _error->Error("Parsing patchfile %s failed: Effected lines end %lu is before start %lu", f.Name().c_str(), e, s);
            } else {
               e = s;
               c = m;
            }
+           if (s > ch.offset)
+              return _error->Error("Parsing patchfile %s failed: Effected line is after previous effected line", f.Name().c_str());
            switch(*c) {
               case 'a':
                  cmdwanted = false;
@@ -422,6 +430,8 @@ class Patch {
                  ch.del_cnt = 0;
                  break;
               case 'c':
+                 if (unlikely(s == 0))
+                    return _error->Error("Parsing patchfile %s failed: Change command can't effect line zero", f.Name().c_str());
                  cmdwanted = false;
                  ch.add = NULL;
                  ch.add_cnt = 0;
@@ -430,6 +440,8 @@ class Patch {
                  ch.del_cnt = e - s + 1;
                  break;
               case 'd':
+                 if (unlikely(s == 0))
+                    return _error->Error("Parsing patchfile %s failed: Delete command can't effect line zero", f.Name().c_str());
                  ch.offset = s - 1;
                  ch.del_cnt = e - s + 1;
                  ch.add = NULL;
@@ -437,9 +449,11 @@ class Patch {
                  ch.add_len = 0;
                  filechanges.add_change(ch);
                  break;
+              default:
+                 return _error->Error("Parsing patchfile %s failed: Unknown command", f.Name().c_str());
            }
         } else { /* !cmdwanted */
-           if (buffer[0] == '.' && buffer[1] == '\n') {
+           if (strcmp(buffer, ".\n") == 0) {
               cmdwanted = true;
               filechanges.add_change(ch);
            } else {
@@ -465,7 +479,8 @@ class Patch {
               }
            }
         }
-      }
+      } while(f.ReadLine(buffer, sizeof(buffer)));
+      return true;
    }
 
    void write_diff(FILE *f)
@@ -543,7 +558,7 @@ class RredMethod : public pkgAcqMethod {
       }
 
    protected:
-      virtual bool URIAcquire(std::string const &Message, FetchItem *Itm) {
+      virtual bool URIAcquire(std::string const &Message, FetchItem *Itm) APT_OVERRIDE {
         Debug = _config->FindB("Debug::pkgAcquire::RRed", false);
         URI Get = Itm->Uri;
         std::string Path = Get.Host + Get.Path; // rred:/path - no host
@@ -601,18 +616,18 @@ class RredMethod : public pkgAcqMethod {
                  << std::endl;
 
            FileFd p;
+           Hashes patch_hash(I->ExpectedHashes);
            // all patches are compressed, even if the name doesn't reflect it
-           if (p.Open(patch_name, FileFd::ReadOnly, FileFd::Gzip) == false) {
-              std::cerr << "Could not open patch file " << patch_name << std::endl;
+           if (p.Open(patch_name, FileFd::ReadOnly, FileFd::Gzip) == false ||
+                 patch.read_diff(p, &patch_hash) == false)
+           {
               _error->DumpErrors(std::cerr);
-              abort();
+              return false;
            }
-           Hashes patch_hash(I->ExpectedHashes);
-           patch.read_diff(p, &patch_hash);
            p.Close();
            HashStringList const hsl = patch_hash.GetHashStringList();
            if (hsl != I->ExpectedHashes)
-              return _error->Error("Patch %s doesn't have the expected hashsum", patch_name.c_str());
+              return _error->Error("Hash Sum mismatch for uncompressed patch %s", patch_name.c_str());
         }
 
         if (Debug == true)
@@ -624,7 +639,6 @@ class RredMethod : public pkgAcqMethod {
         FILE *out = fopen(Itm->DestFile.c_str(), "w");
 
         Hashes hash(Itm->ExpectedHashes);
-
         patch.apply_against_file(out, inp, &hash);
 
         fclose(out);
@@ -657,6 +671,16 @@ class RredMethod : public pkgAcqMethod {
         return true;
       }
 
+      bool Configuration(std::string Message) APT_OVERRIDE
+      {
+        if (pkgAcqMethod::Configuration(Message) == false)
+           return false;
+
+        DropPrivsOrDie();
+
+        return true;
+      }
+
    public:
       RredMethod() : pkgAcqMethod("2.0",SingleInstance | SendConfig), Debug(false) {}
 };
@@ -685,7 +709,11 @@ int main(int argc, char **argv)
         _error->DumpErrors(std::cerr);
         exit(1);
       }
-      patch.read_diff(p, NULL);
+      if (patch.read_diff(p, NULL) == false)
+      {
+        _error->DumpErrors(std::cerr);
+        exit(2);
+      }
    }
 
    if (just_diff) {