diff options
| -rw-r--r-- | src/bech32.cpp | 8 | ||||
| -rw-r--r-- | src/bech32.h | 2 |
2 files changed, 8 insertions, 2 deletions
diff --git a/src/bech32.cpp b/src/bech32.cpp index d6b29391a9..4c966350b4 100644 --- a/src/bech32.cpp +++ b/src/bech32.cpp @@ -4,6 +4,8 @@ #include <bech32.h> +#include <assert.h> + namespace { @@ -58,7 +60,7 @@ uint32_t PolyMod(const data& v) // During the course of the loop below, `c` contains the bitpacked coefficients of the // polynomial constructed from just the values of v that were processed so far, mod g(x). In - // the above example, `c` initially corresponds to 1 mod (x), and after processing 2 inputs of + // the above example, `c` initially corresponds to 1 mod g(x), and after processing 2 inputs of // v, it corresponds to x^2 + v0*x + v1 mod g(x). As 1 mod g(x) = 1, that is the starting value // for `c`. uint32_t c = 1; @@ -145,6 +147,10 @@ namespace bech32 /** Encode a Bech32 string. */ std::string Encode(const std::string& hrp, const data& values) { + // First ensure that the HRP is all lowercase. BIP-173 requires an encoder + // to return a lowercase Bech32 string, but if given an uppercase HRP, the + // result will always be invalid. + for (const char& c : hrp) assert(c < 'A' || c > 'Z'); data checksum = CreateChecksum(hrp, values); data combined = Cat(values, checksum); std::string ret = hrp + '1'; diff --git a/src/bech32.h b/src/bech32.h index 2e2823e974..fb39cd352b 100644 --- a/src/bech32.h +++ b/src/bech32.h @@ -19,7 +19,7 @@ namespace bech32 { -/** Encode a Bech32 string. Returns the empty string in case of failure. */ +/** Encode a Bech32 string. If hrp contains uppercase characters, this will cause an assertion error. */ std::string Encode(const std::string& hrp, const std::vector<uint8_t>& values); /** Decode a Bech32 string. Returns (hrp, data). Empty hrp means failure. */ |